Int to enum question
I have an old program, the method take an int as parameter, in side the method, I check each int value and take action like:
switch(i)
case Const.A: ...
case Const.B: ...
Const is a class defined sone constant values like
static final int A = 1;
static final int B = 2;
now, I would like to change Const to a enum. define A, B as enum's elements. but i don't want to change method's parameter, which means the method still take int as parameter. how can I map the passed in int to each enum element
now, I would like to change Const to a enum. define
A, B as enum's elements. but i don't want to change
method's parameter, which means the method still take
int as parameter. how can I map the passed in int to
each enum elementWhy are you not able (or desiring) to change the method to accept an enum parameter?
One way to get the enum's ordinality is to use the ordinal method. This is kind of the converse to what jverd was showing you.
myMethod(myEnum.ordinal()); //changes enum to its integerBut as jverd states, best to use enums as enums and integers as integers.
Similar Messages
-
I am iterating in a while loop and using the index terminal to build an array of differnet values of the same enumerated type control that are from a strict type def enumerated control. What I want to do is to iterate and do a comparison and if the comparison holds, I want to build an array of the correlating enumerated types so that I can use this later on.
I am using a Function that came with the state diagram toolkit called "int to enum" that the state diagram uses when calculating its next state info. It seems to bomb out when I attempt to wire my enum type control to its input.
Any ideas?I have not used the state diagram toolkit but have extensively employed enums from typedefs. This is very convenient since for comparisons just compare it to a constant version of the typedefs. If you use a strict typedef remember that almost everything must be identical and this causes many problems. Since typedefs of enums rarely have to be strict I would think about why you chose a strict type def as opposed to a normal typedef. One additional added feature is that when wiring a enum typedef to a case structure you can populate the case with the enum named cases. I would speculate that your problems are due to the use of a strict typedef which is only necessary when you are concerned with more than just a typdef's structure and values (i.e aesthetic properties). Hope this helps (again I have not used the state diagram toolkit).
-Paul
Paul Falkenstein
Coleman Technologies Inc.
CLA, CPI, AIA-Vision
Labview 4.0- 2013, RT, Vision, FPGA -
Hi,
Just looking for a bit of advice on this piece of code. My main method involves the user entering the size in inches. Based on this I want to calculate the appropriate enum value based on their entry. Is the getSize() method below the only way to do this using an enum?
(I realize I could use an array etc but I'm just looking to try out enums)
public enum JerseySize {
XL("42-44"),
L("38-41"),
M("36-37"),
S("33-35");
private String inInches;
JerseySize(String i){
this.inInches = i;
public static JerseySize getSize(String s)
for(JerseySize js : JerseySize.values())
if (js.inInches.equals(s))
return js;
return null;
}It's almost always better to keep information in as specific a type as you can. So for a whole number of inches, use an int rather than a string. For two such numbers, you can use two ints, or - in this specific case - you know the max is one less than the min of the next, you could iterate through the values to get it. So I'd use JerseySize(int minInches, int maxInches) and have a boolean contains (int inches) method.
-
Can someone explain these program.
1. In IsFlagDefined method when i print e.ToString() it prints different outputs on each iteration.I am not able to understand the logic behind the output can someone explain me step by step.Also i am not able to reply to others it always says
Body text cannot contain images or links until we are able to verify your account.
Please help me on these too.
static bool IsFlagDefined (Enum e)
decimal d;
Console.WriteLine(e.ToString());
return !decimal.TryParse(e.ToString(), out d);
[Flags]
public enum BorderSides { Left=1, Right=2, Top=4, Bottom=8 }
static void Main()
for (int i = 0; i <= 16; i++)
BorderSides side = (BorderSides)i;
IsFlagDefined (side);Hi SriNath,
1) For the problem of message "Body text cannot contain images or links until we are able to verify your account. " you need to verify your account by clicking the link in email send by MSDN forums.
Once you verify your account you are able to put link and images in your post.
2) It's easy if you pass Left it will shows 1, for right 2, top 4 and bottom 8. It's giving a sum of ENUM.
For example if i = 3 it prints left + right (1+ 2) = 3
so it's easy.
and if you want to post code in your post please use code dialog so we can read it easily.
Hope it helps.
Thanks,
Nans11
ENjoy ThE WorLD Of COdE -
Int dereferencing error question
Hey what does the error "int cannt be dereferenced" mean. I get it when im calling a method with a variable read in from a file?
Java has two families of types: primitive types and reference types.
Primitves: byte, char, short, int, long, float, double, boolean.
References: Refer to objects, interfaces and arrays. People often simply think of them as "objects," which is a good enough approximation in many cicrcumstances.
To dereference is when you use the dot to get to a member (variable or method) that a reference refers to.
Object obj = new Object();
System.out.println(obj.hashCode());In the second line, we dereference obj to access its hashCode method.
Primitives (like int) don't have members, so you can't dereference them.int i = 5;
System.out.println(i.hashCode()); // can't do it. i doesn't refer to an object, so there are no methods associated with it -
When comparing enum values: it's ok to use the == comparator, right?
When comparing enum values: it's ok to use the ==
comparator, right?Correct.
Kaj -
Hello beautiful folks of the lenovo community.
I am traveling oversees next week to Doha, Qatar where the power outlets are 220V with either the Indian or UK plug head.
Will the 520's power brick switch over the voltage, or should I bring my step down converter for good measure?
Cheers,
DylanFor travelling I bought a 135W power brick because of its somewhat smaller size. Same weight though. Works great.
W520 4270CTO i7-2820QM Quadro2000M 1920x1080 Display 16GB RAM 2x240GB Intel 510 SSDs (RAID 0) - BIOS 1.42 - PCMark7:4,568
Samsung Series 9 15-inch NP900X4C-A03US - PCMark7: 4674 -
Getting int values from a char array
Hi,
I need to make a fast program which reads lots of data from files and process them. I need to interpret these data as int's. To be more efficient and avoid to make a lot of disk access, I allocate in memory buffers part of the data, then process it and then allocate new data. The problem is that if I want to allocate data in memory buffers, all the methods that enables me to do that receceive as a parameter only a an array of chars, and as I have mentioned I need to interpret the data as a 4 bytes int. The static methods of Array to get the int value from a position ar not useful because the onlye get the int value of the indexed byte (or char); this method doesn't take 4 bytes from the index to build an int.
My question is: is there any way to build an int from 4 bytes? or can I get the int's in this way directly from the buffer?
Thank you,Isn't this one of the prime examples of using java.io.DataOutputStream and java.io.DataInputStream?
-
Questions about a MasterQuize program
Hi, everyone.
I got a in-class case study program like this in the class:
* This class stores/represents a question that has one of two
* answers: True or False.
* <p></p>
* It needs to track the following information:
* <ul>
* <li>Question text</li>
* <li>Correct answer</li>
* <li>The user's answer to the question</li>
* <li>Points value</li>
* <li>Category</li>
* <li>Difficulty rating</li>
* </ul>
// Our question should allow us to do the following:
// - Create question (constructor) -- may be overloaded
// - Print (display) question
// - Check client's answer for correctness
// - Get points value for question (0 or max)
// - Add "No-BS" grading option
// - Getting client's answer
// - Check to see if answered by client
public class TrueFalseQuestion
// Class constants (to simplify changes to common values)
public static final int MIN_DIFFICULTY_LEVEL = 1;
public static final int MAX_DIFFICULTY_LEVEL = 5;
public static final int DEFAULT_DIFFICULTY_LEVEL = 1;
public static final int DEFAULT_POINT_VALUE = 1;
public static final String DEFAULT_CATEGORY_VALUE = "none";
// Class instance variables
private String questionText;
private String correctAnswer;
private String userAnswer;
private int pointsValue;
private String category;
private int difficultyLevel; // TODO: Set a range for difficulty levels
* @param text The literal wording of this question
* @param answer The correct answer for this question
* @param pts The total points available for this question
* @param ctgry Category keyword for this question
* @param level The perceived/intended difficulty level of this question
* <p></p>
* Defines a TrueFalseQuestion object.
public TrueFalseQuestion (String text, String answer, int pts, String ctgry, int level)
// Set starting values for all instance variables
questionText = text.trim();
correctAnswer = answer.trim();
userAnswer = null; // No user answer supplied yet
if (pts >= 1) // We assume that every problem is worth at least 1 point
pointsValue = pts;
else
pointsValue = DEFAULT_POINT_VALUE;
category = ctgry.trim();
if (level >= MIN_DIFFICULTY_LEVEL && level <= MAX_DIFFICULTY_LEVEL) // within range
difficultyLevel = level;
else
difficultyLevel = DEFAULT_DIFFICULTY_LEVEL;
// Simplified (overloaded) constructors
* @param text The literal wording of this question
* @param answer The correct answer for this question
* @param pts The total points available for this question
* <p></p>
* Defines a TrueFalseQuestion with default values for category and difficulty level.
public TrueFalseQuestion (String text, String answer, int pts)
// Call pre-existing constructor with default category and difficulty
this(text, answer, pts, DEFAULT_CATEGORY_VALUE, DEFAULT_DIFFICULTY_LEVEL);
* @param text The literal wording of this question
* @param answer The correct answer for this question
* <p></p>
* Defines a TrueFalseQuestion with the default point value, default category,
* and default difficulty level.
public TrueFalseQuestion (String text, String answer)
// Call pre-existing constructor with default points, category and difficulty
this(text, answer, DEFAULT_POINT_VALUE, DEFAULT_CATEGORY_VALUE,
DEFAULT_DIFFICULTY_LEVEL);
* @param text The literal wording of this question
* @param answer The correct answer for this question
* @param pts The total points available for this question
* @param ctgry Category keyword for this question
* <p></p>
* Defines a TrueFalseQuestion with the default difficulty level.
public TrueFalseQuestion (String text, String answer, int pts, String ctgry)
// Call pre-existing constructor with default points, category and difficulty
this(text, answer, pts, ctgry,
DEFAULT_DIFFICULTY_LEVEL);
* @param text The literal wording of this question
* @param answer The correct answer for this question
* @param ctgry Category keyword for this question
* <p></p>
* Defines a TrueFalseQuestion with the default point value and the default
* difficulty level.
public TrueFalseQuestion (String text, String answer, String ctgry)
// Use default points and difficulty
this(text, answer, DEFAULT_POINT_VALUE, ctgry, DEFAULT_DIFFICULTY_LEVEL);
* @param text The literal wording of this question
* @param answer The correct answer for this question
* @param pts The total points available for this question
* @param level The perceived/intended difficulty level of this question
* <p></p>
* Defines a TrueFalseQuestion with the default value for the question category.
public TrueFalseQuestion (String text, String answer, int pts, int level)
// Use default category
this(text, answer, pts, DEFAULT_CATEGORY_VALUE, level);
// Clients can invoke this method to retrieve the text of the current question.
// We chose to return the text instead of printing it; this allows the client
// to decide how it should be presented (via a GUI, over a network, etc.)
public String getQuestion ()
return questionText;
// This method allows the client to store the user's answer inside the
// TrueFalseQuestion object for easy comparison
public void submitAnswer (String ans)
userAnswer = ans;
// This method reports whether the submitted answer matches the correct answer
public boolean answerIsCorrect(String userAns) // This version does all the work
if (userAns == null) // No response from user (yet)
return false;
else
// Normalize and compare answers
char key = normalize(correctAnswer); // Get 't' or 'f'
char ans = normalize(userAns); // Get 't' or 'f'
return (key == ans);
public boolean answerIsCorrect ()
return answerIsCorrect(userAnswer); // Call previously-defined version
public int getPointsValue()
return pointsValue;
// Return the points awarded for the user's answer. This method does
// NOT support partial credit; answers are either correct or incorrect.
// If the "No-BS" option is selected, blank (unanswered) questions receive
// 1 point automatically; otherwise, the score will be either 0 or the
// question's normal points value.
public int getPointsEarned(boolean useNoBSRule)
System.out.println("useNoBS: " + useNoBSRule + "\tuserAnswer: " + userAnswer + "\tcorrectAnswer: " + correctAnswer);
if (useNoBSRule && (userAnswer == null))
return 1;
else if (userAnswer == null)
return 0; // Without "No-BS", treat blank problems as incorrect
if (answerIsCorrect() == false)
return 0;
else
return pointsValue;
// This method returns true if the user has submitted an answer
// for this question (regardless of whether that answer is correct)
public boolean hasBeenAnswered ()
return (userAnswer != null);
// Private helper method to convert all answers to single lowercase
// letters (in this case, 't' for TRUE and 'f' for FALSE)
private char normalize (String input)
if (input != null)
input = input.trim(); // Remove leading whitespace
input = input.toLowerCase();
return input.charAt(0);
else
return ' ';
import java.util.*;
* This class represents a complete test or quiz.
* Data stored:
* - List of questions
* - Total score earned
* - Total score possible
* - Name/title of test
* - Instructions
* - Category/class assignment
* - Student (test-taker) name
* - Date test is/was taken
* - Time started
* - Time completed
* - Maximum time allotted
* - (List of) Maximum attempts per question
* - List of attempts per question
* - List of difficulty ratings per question
* - Assignment weight
* Methods:
* - Constructor
* - Add question
* - Display question
* - Display test
* - Display instructions
* - Generate random exam
* - Take/administer test
* - Get score
* STUFF TO DO:
* - Add time/date restrictions
* - Add network access restrictions
* - Add other restrictions/allowances?
* @author (your name)
* @version (a version number or a date)
public class Test
// Class constant
public static final int MAX_NUMBER_OF_QUESTIONS = 10;
// Class instance variables
private String testName;
private int scoreEarned; // What the student earned on the exam
private int scorePossible; // Total point values of all questions
private String instructions; // Exam header text
private ArrayList<TrueFalseQuestion> questions; // Create inside constructor
// Methods
public Test (String name, String instr)
testName = name;
scoreEarned = 0;
scorePossible = 0;
instructions = instr;
questions = new ArrayList<TrueFalseQuestion>(); //[MAX_NUMBER_OF_QUESTIONS];
public String getInstructions()
return instructions;
public int getScore()
return scoreEarned;
public void addQuestion (TrueFalseQuestion q)
scorePossible += q.getPointsValue();
questions.add(q); // Automatically append question to end of test
public String displayQuestion (int position)
if (position < questions.size())
return (position+1) + ". " + questions.get(position).getQuestion();
else
return null;
public String displayTest ()
String result = "";
for (int i = 0; i < questions.size(); i++)
result += (i+1) + ". (";
TrueFalseQuestion t = questions.get(i);
result += t.getPointsValue();
result += " points)\n\n" + displayQuestion(i);
result += "\n\n";
return result;
// Get test length (number of questions)
public int length ()
return questions.size();
// Submit answer to a specific question
public boolean answer(int number, String a)
// Question numbers run from 0-(max-1) -- THIS WAS AN OFF-BY-ONE ERROR AT FIRST
if (number >= 0 && number < questions.size())
TrueFalseQuestion t = questions.get(number);
t.submitAnswer(a);
return true; // Question was answered
else
return false; // Unable to answer (nonexistent) question
// Score exam
public void scoreExam (boolean useNoBS)
scoreEarned = 0;
for (int i = 0; i < questions.size(); i++) // For each question in exam
TrueFalseQuestion t = questions.get(i); // get current question
scoreEarned += t.getPointsEarned(useNoBS);
}// Test harness for the Test and *Question classes
import java.util.*;
public class QuizDriver
public static void main(String[] args)
// Create a new Test object
Test exam = new Test("Sample Exam", "Select the correct answer for each question");
setUp(exam);
Scanner sc = new Scanner(System.in);
System.out.println(exam.getInstructions());
// Administer exam
for (int i = 0; i < exam.length(); i++)
// Print out current question
System.out.println(exam.displayQuestion(i));
// Get user answer
System.out.print("Your answer: ");
String ans = sc.nextLine();
if (ans.equals("")) // Handle blank responses for unanswered questions
ans = null;
exam.answer(i, ans);
// Get exam results
exam.scoreExam(true);
System.out.println("Your final score was " + exam.getScore() + " points.");
private static void setUp (Test t)
TrueFalseQuestion x = new TrueFalseQuestion("The sky is blue.", "true", 2);
t.addQuestion(x);
x = new TrueFalseQuestion("The first FORTRAN compiler debuted in 1957", "true", 5);
t.addQuestion(x);
x = new TrueFalseQuestion("Spock was a Vulcan", "false", 3);
t.addQuestion(x);
}This program is far from finishing.
I have many questions about this program, but let me ask this one first:
In the TrueFalseQeustion class, why are there so many constructors? What is the purpose of setting some of the variables to default values?
Thank you very much!!!
Edited by: Terry001 on Apr 16, 2008 10:02 AMnewark wrote:
Stop ignoring the error messages. You seem to think that an error message means you're doing the assignment wrong. It's probably a simple fix. Post the exact error messages, as well as the code that corresponds to them. The error message will tell you exactly what line the problem occurs on, so you know right where to look.Hi,
After some modifications, the program now gives me the result the assignment wants when I run it. But I still have trouble with the MultipleChoiceQuestion class
Here is the complete program
QuizDriver class
// Test harness for the Test and *Question classes
import java.util.*;
public class QuizDriver
public static void main(String[] args)
// Create a new Test object
Test exam = new Test("Sample Exam", "Select the correct answer for each question");
setUp(exam);
Scanner sc = new Scanner(System.in);
System.out.println(exam.getInstructions());
// Administer exam
for (int i = 0; i < exam.length(); i++)
// Print out current question
System.out.println(exam.displayQuestion(i));
// Get user answer
System.out.print("Your answer: ");
String ans = sc.nextLine();
if (ans.equals("")) // Handle blank responses for unanswered questions
ans = null;
exam.answer(i, ans);
// Get exam results
exam.scoreExam(true);
System.out.println("Your final score was " + exam.getScore() + " points.");
private static void setUp (Test t)
Question x;
x = new TrueFalseQuestion("The sky is blue.", "true", 2);
t.addQuestion(x);
x = new TrueFalseQuestion("The first FORTRAN compiler debuted in 1957", "true", 5);
t.addQuestion(x);
x = new TrueFalseQuestion("Spock was a Vulcan", "false", 3);
t.addQuestion(x);
x = new MultipleChoiceQuestion("What is the color of the car\na.Red\nb.Green", "a. Red", 3);
t.addQuestion(x);
x = new MultipleChoiceQuestion("What is the name of this class\na.CSE110\nb.CSE114", "b, CSE114", 3);
t.addQuestion(x);
}Test
public class Test
// Class constant
public static final int MAX_NUMBER_OF_QUESTIONS = 10;
// Class instance variables
private String testName;
private int scoreEarned; // What the student earned on the exam
private int scorePossible; // Total point values of all questions
private String instructions; // Exam header text
private ArrayList<Question> questions; // Create inside constructor
// Methods
public Test (String name, String instr)
testName = name;
scoreEarned = 0;
scorePossible = 0;
instructions = instr;
questions = new ArrayList<Question>(); //[MAX_NUMBER_OF_QUESTIONS];
public String getInstructions()
return instructions;
public int getScore()
return scoreEarned;
public void addQuestion (Question q)
scorePossible += q.getPointsValue();
questions.add(q); // Automatically append question to end of test
public String displayQuestion (int position)
if (position < questions.size())
return (position+1) + ". " + questions.get(position).getQuestion();
else
return null;
public String displayTest ()
String result = "";
for (int i = 0; i < questions.size(); i++)
result += (i+1) + ". (";
Question t = questions.get(i);
result += t.getPointsValue();
result += " points)\n\n" + displayQuestion(i);
result += "\n\n";
return result;
// Get test length (number of questions)
public int length ()
return questions.size();
// Submit answer to a specific question
public boolean answer(int number, String a)
// Question numbers run from 0-(max-1) -- THIS WAS AN OFF-BY-ONE ERROR AT FIRST
if (number >= 0 && number < questions.size())
Question t = questions.get(number);
t.submitAnswer(a);
return true; // Question was answered
else
return false; // Unable to answer (nonexistent) question
// Score exam
public void scoreExam (boolean useNoBS)
scoreEarned = 0;
for (int i = 0; i < questions.size(); i++) // For each question in exam
Question t = questions.get(i); // get current question
scoreEarned += t.getPointsEarned(useNoBS);
}Question
public class Question
// Class constants
public static final int MIN_DIFFICULTY_LEVEL = 1;
public static final int MAX_DIFFICULTY_LEVEL = 5;
public static final int DEFAULT_DIFFICULTY_LEVEL = 1;
public static final int DEFAULT_POINT_VALUE = 1;
public static final String DEFAULT_CATEGORY_VALUE = "none";
// Class instance variables
protected String questionText;
protected String correctAnswer;
protected String userAnswer;
protected int pointsValue;
protected String category;
protected int difficultyLevel; //TODO: set a range for difficulty levels
// Constructors
public Question (String text, String answer, int pts, String ctgry, int level)
questionText = text.trim();
correctAnswer = answer.trim();
userAnswer = null;
if (pts >= 1)
pointsValue = pts;
else
pointsValue = DEFAULT_POINT_VALUE;
category = ctgry.trim();
if (level >= MIN_DIFFICULTY_LEVEL && level <= MAX_DIFFICULTY_LEVEL)
difficultyLevel = level;
else
difficultyLevel = DEFAULT_DIFFICULTY_LEVEL;
// Overloaded (simplied) constructors
public Question (String text, String answer, int pts)
this(text, answer, pts, DEFAULT_CATEGORY_VALUE, DEFAULT_DIFFICULTY_LEVEL);
public Question (String text, String answer, int pts, String ctgry)
this(text, answer, pts, ctgry, DEFAULT_DIFFICULTY_LEVEL);
public Question (String text, String answer, String ctgry)
this(text, answer, DEFAULT_POINT_VALUE, ctgry, DEFAULT_DIFFICULTY_LEVEL);
public Question (String text, String answer, int pts, int level)
this(text, answer, pts, DEFAULT_CATEGORY_VALUE, level);
// Methods
public String getQuestion ()
return questionText;
// Use this method to store user answers
public void submitAnswer (String ans)
userAnswer = ans;
public boolean answerIsCorrect (String userAns)
if (userAns == null)
return false;
else
// Normalize and compare answers
char key = normalize (correctAnswer); //Get the first letter of an answer
char ans = normalize (userAns); //Get the first letter of an answer
return (key == ans);
public boolean answerIsCorrect ()// Why do we need two answerisCorrect() methods?
return answerIsCorrect (userAnswer);
public int getPointsValue ()
return pointsValue;
public int getPointsEarned (boolean userNoBSRule)
System.out.println ("useNoBS: " + userNoBSRule + "\tuseAnswer: " + userAnswer + "\tcorrectAnswer: " + correctAnswer);
if (userNoBSRule && (userAnswer == null))
return 1;
else if (userAnswer == null)
return 0;
if (answerIsCorrect() == false)
return 0;
else
return pointsValue;
public String getCorrectAnswer ()
return correctAnswer;
public boolean hasBeenAnswered ()
return (userAnswer != null);
private char normalize (String input)
if (input != null)
input = input.trim();
input = input.toLowerCase();
return input.charAt(0);
else
return ' ';
TrueFalseQuestion
public class TrueFalseQuestion extends Question
public TrueFalseQuestion (String text, String answer, int pts, String ctgry, int level)
super(text, answer, pts, ctgry, level);
public TrueFalseQuestion (String text, String answer, int pts)
super(text, answer, pts, DEFAULT_CATEGORY_VALUE, DEFAULT_DIFFICULTY_LEVEL);
public TrueFalseQuestion (String text, String answer, int pts, String ctgry)
super(text, answer, pts, ctgry, DEFAULT_DIFFICULTY_LEVEL);
public TrueFalseQuestion (String text, String answer, String ctgry)
super(text, answer, DEFAULT_POINT_VALUE, ctgry, DEFAULT_DIFFICULTY_LEVEL);
public TrueFalseQuestion (String text, String answer, int pts, int level)
super(text, answer, pts, DEFAULT_CATEGORY_VALUE, level);
// Methods
public String[] getPossibleAnswerChoice ()
String[] possibleAnswerChoice = {"true", "false"};
return possibleAnswerChoice;
} MultipleChoiceQuestion
public class MultipleChoiceQuestion extends Question
public MultipleChoiceQuestion (String text, String answer, int pts, String ctgry, int level)
super(text, answer, pts, ctgry, level);
public MultipleChoiceQuestion (String text, String answer, int pts)
super(text, answer, pts, DEFAULT_CATEGORY_VALUE, DEFAULT_DIFFICULTY_LEVEL);
public MultipleChoiceQuestion (String text, String answer, int pts, String ctgry)
super(text, answer, pts, ctgry, DEFAULT_DIFFICULTY_LEVEL);
public MultipleChoiceQuestion (String text, String answer, String ctgry)
super(text, answer, DEFAULT_POINT_VALUE, ctgry, DEFAULT_DIFFICULTY_LEVEL);
public MultipleChoiceQuestion (String text, String answer, int pts, int level)
super(text, answer, pts, DEFAULT_CATEGORY_VALUE, level);
// Methods
String possibleAnswers;
public String getPossibleAnswers ()
return possibleAnswers;
public void addAnswerChoice (String answerChoice)
String ansChoice = answerChoice;
questionText += "\nansChoice";
possibleAnswers = answerChoice;
public void printAnswerChoice ()
System.out.println (questionText);
} I don't understand why the assignment wants me to build a method in the MultpleChoiceQuestion class to store the potential answer choices, I can make the program display the potential answer choices by including them in the questionText as following in the QuizDriver class
Question x;
x = new MultipleChoiceQuestion("What is the color of the car\na.Red\nb.Green", "a. Red", 3);
t.addQuestion(x); I don't know how to allow the client to construct the list of answer choices one at a time(add one potential answer choice by calling the addAsnwerChoices() method once)
Here are a few original sentences of my assignment which describe what I should do with the MultipleChoiceQuestion class
Using TrueFalseQuestion as a model, develop a new MultipleChoiceQuestion class that can be used to represent a problem where the user must select one of several answer choices (e.g., "Select answer (a), (b), (c), or (d)."). This new question type should have all of the same externally-visible functionality as TrueFalseQuestion, except that it must:
maintain a list of potential answer choices
provide a method that allows the client to construct the list of answer choices one at a time (i.e., the client should be able to call an addAnswerChoice() method to pass a new answer option to the MultipleChoiceQuestion.)
display (as part of the question text) the list of answer choices with appropriate letters ("abcd" instead of "0123") I don't understand what these sentences mean.
1. "Maintain a list of potential answer choices"-- this reminds me of the getPossibleAnswerChoice() method in the TrueFalseQuestion class
public String[] getPossibleAnswerChoice ()
String[] possibleAnswerChoice = {"true", "false"};
return possibleAnswerChoice;
}I wonder that if the potential answer choices I have to store in the MultipleChoiceQuestion class are only letters "a", "b", "c", "d", etc, or include the answer text coming after the letters(eg. a.Red, b.Green)
2. "provide a method that allows the client to construct the list of answer choices one at a time". How do I achieve the functionality "one at a time"? Do I need to pass the input of the client (a potential answer choice) to the variable of the method which stores the list of potential answers?
3. "display (as part of the question text) the list of answer choices with appropriate letters". My question here is that: When the client type in one possible answer, should I append it to the variable questionText? (So I use the questionText variable in the methods of the first and second steps)
Thank you very much for your nice help!
Edited by: Terry001 on Apr 21, 2008 8:01 AM -
Hi,
As per the rule, any numeric literal is by default a int, and implicit type casting means assigning a smaller thing (eg:byte) to a bigger container(eg: int).
My question is :
Why does the compiler doesn't throw any errro when the following statement is executed :
byte b = 12;
as here 12 is a numeric literal( ie of type int) and b is of type byte.
Hence we would need a explicit casting right ?. But this is not the case.
The above statement doesn't give any error.
Thanks in advanceHi Amit,
byte b=12;In this case 12 is known at compile time and it is in range of byte(-128 to 127). Hence no issue.
But b=128 will result in error.(out of range for byte)
similarly
byte a=12;
byte b=a; will result in error because a is not known at compile time.
so final byte a =12;
byte b=a; will compile fine since a is compile time constant.
Hope this helps... -
I do not use J2SE 5.0, and I need to use an enumerator-like construct. My original code was:
// Constants to be used with runnersOnBase
public static final short RUNNER_ON_FIRST = 1;
public static final short RUNNER_ON_SECOND = 2;
public static final short RUNNER_ON_THIRD = 4;Obviously this is not a great practice, so I decided to try typesafe enums, which are explained here: http://java.sun.com/developer/Books/shiftintojava/page1.html#replaceenums
The problem I'm having comes from the fact that, in my program, I can add the integer constants together. Is there a similar way to do that with typesafe enums, and if so, how should the enum class be set up? Thanks a lot. Take care.The problem I'm having comes from the fact that, in
my program, I can add the integer constants together.
Is there a similar way to do that with typesafe
enums, and if so, how should the enum class be set
up? Thanks a lot. Take care.Something like
public class Enum {
private static Map enums;
public static Enum A = new Enum();
public static Enum B = new Enum();
public static Enum C = new Enum();
static {
enums.add( Integer.valueOf( 0 ), A );
enums.add( Integer.valueOf( 0 ), B );
enums.add( Integer.valueOf( 0 ), C );
public static Enum add( Enum a, Enum b ) {
int av = enums.get( a );
int bv = enums.get( b );
Enum value = enums.get( Integer.valueOf( av + bv ) );
// if( value == null ) throw some exception maybe?
return value;
}maybe? -
How to search with multiple constraints in the new java API?
I'm having a problem using the new MDM API to do searches with multiple constraints. Here are the classes I'm trying to use, and the scenario I'm trying to implement:
Classes:
SearchItem: Interface
SearchGroup: implements SearchItem, empty constructor,
addSearchItem (requires SearchDimension and SearchConstraint, or just a SearchItem),
setComparisonOperator
SearchParameter: implements SearchItem, constructor requires SearchDimension and SearchConstraint objects
Search: extends SearchGroup, constructor requires TableId object
RetrieveLimitedRecordsCommand: setSearch method requires Search object
FieldDimension: constructor requires FieldId object or FieldIds[] fieldPath
TextSearchConstraint: constructor requires string value and int comparisonOperator(enum)
BooleanSearchConstraint: constructor requires boolean value
Scenario:
Okay, so say we have a main table, Products. We want to search the table for the following:
field IsActive = true
field ProductColor = red or blue or green
So the question is how to build this search with the above classes? Everything I've tried so far results in the following error:
Exception in thread "main" java.lang.UnsupportedOperationException: Search group nesting is currently not supported.
at com.sap.mdm.search.SearchGroup.addSearchItem(Unknown Source)
I can do just the ProductColor search like this:
Search mySearch = new Search(<Products TableId>);
mySearch.setComparisonOperator(Search.OR_OPERATOR);
FieldDimension myColorFieldDim = new FieldDimension(<ProductColor FieldId>);
TextSearchConstraint myTextConRed = new TextSearchConstraint("red",TextSearchConstraint.EQUALS);
TextSearchConstraint myTextConBlue = new TextSearchConstraint("blue",TextSearchConstraint.EQUALS);
TextSearchConstraint myTextConGreen = new TextSearchConstraint("green",TextSearchConstraint.EQUALS);
mySearch.addSearchItem(myColorFieldDim,myTextConRed);
mySearch.addSearchItem(myColorFieldDim,myTextConBlue);
mySearch.addSearchItem(myColorFieldDim,myTextConGreen);
the question is how do I add the AND of the BooleanSearchConstraint?
FieldDimension myActiveFieldDim = new FieldDimension(<IsActive FieldId>);
BooleanSearchConstraint myBoolCon = new BooleanSearchConstraint(true);
I can't just add it to mySearch because mySearch is using OR operator, so it would return ALL of the Products records that match IsActive = true. I tried creating a higher level Search object like this:
Search topSearch = new Search(<Products TableId>);
topSearch.setComparisonOperator(Search.AND_OPERATOR);
topSearch.addSearchItem(mySearch);
topSearch.addSearchItem(myActiveFieldDim,myBoolCon);
But when I do this I get the above "Search group nesting is currently not supported" error. Does that mean this kind of search cannot be done with the new MDM API?I'm actually testing a pre-release of SP05 right now, and it still is not functional. The best that can be done is to use a PickListSearchConstraint to act as an OR within a field. But PickList is limited to lookup Id values, text attribute values, numeric attribute values and coupled attribute values. It works for me in some cases where I have lookup Id values, but not in other cases where the users want to search on multiple text values within a single field.
-
I have bunches of Enums that I want to have a common behavior, so I created an interface, and implement that in each enum:
interface Z {
int doStuff();
enum X implements Z {
A, B, C;
int doStuff(){ ... }
}Now I want to use an EnumMap with keys consisting of enums implementing Z:
MyClass c = ...
EnumMap <Z, MyClass> map = new EnumMap <Z, MyClass>( Z.class );
for ( Z z : X.values()){
map.put( x, c );
}The compiler does not like the declaration (among other things). If I replace the declaration with:
EnumMap <? extends Z, MyClass> map = new EnumMap <Z, MyClass>( Z.class );then it likes the declaration to the left of the "=", but not the rest.
What am I doing wrong? Note that if I replace the EnumMap declaration with:
HashMap <Z, MyClass> map = new HashMap <Z, MyClass>();Then everything works, but would like to use EnumMap. If I declare:
EnumMap map = new EnumMap( Z.class );then I have to do some casting, and also get unchecked warnings.Thanks for the response! In my example, I'm only putting enums from one enum class in there; in fact, I thought the whole purpose of having to pass a class object for the Enum to the constructor, was to identify the class.
Oh, well, if it wasn't meant to work, I'll go back to the HashMap.
Another question: Along the same vein, I have the following "awful" utility routine:
public static Enum getEnum( Object[] enums, String string ){
return Enum.valueOf( ((Enum) enums[ 0 ]).getClass(), string );
}I have many groups of enums that are identified by name in external data. When I read the external data, I need to identify them with the actual enum element. The valueOf() method is of course perfect for this. Unfortunately, all I have in the routine that reads the data, is the array of values; eg, X.values() (from my enum X in my original message) is passed in.
The above code works perfectly (and even throws the appropriate exception when there is no match), but gives another unchecked conversion message. Any ideas as to how to get rid of the message? Subclassing each enum to have a lookup() method that just maps to valueOf() would probably work, but it's clumsy and not really practical with about a hundred enum declarations.
I thought the whole point of casting in Java was to in effect say, "Check this at run-time; I know what I'm doing." -
Lost and I need help or point in right direction
Trying to parse an xml file pass a String[] to my bean and have the jsp display the String. User clicks button get the next String in the array.
All I keep getting is InstantionException when I run it.
Code that parses and passes String to bean:
new parseData(xmlFile);// parse it
DataBean bean = new DataBean(questionText);// pass String[] to bean
bean.setQuestionText(1);// set the first String
String cmd = null;
try{
cmd = "rundll32 url.dll,FileProtocolHandler http://localhost:8080/mywebapp/index.jsp";
Process p = Runtime.getRuntime().exec(cmd);
} catch(Exception e ){}The DataBean:
package webapp;
import java.beans.*;
import javax.swing.*;
public class DataBean extends Object implements java.io.Serializable {
private String buttonText;
private String[] questionText;
private String question;
/** Creates new DataBean */
public DataBean(String[] questionText) {
this.questionText = questionText;
System.out.println( getQuestionText() + " <<<< " );
// setter methods for questions and answers
public void setQuestionText(int quesNumber){
this.question = questionText[quesNumber];
public String getQuestionText(){
return question;
}And finally the jsp page
<%@ page contentType="text/html"%>
<html>
<head><title>Select Survey to Load Page</title></head>
<body>
<jsp:useBean id='dataBean' scope='session' class='webapp.DataBean'/>
<jsp:setProperty name='dataBean' property='question'/>
<div align="center">
<%int j = 0;%>
<p><Font color = "white" size="5"><%=dataBean.getQuestionText()%>></Font></p>?
<form><input type="button"onclick="<%j++; dataBean.setQuestionText(j);%>window.reset()" value='Click me!'</form>
</body>
</html>can you post the original error and stack trace?
-
Pro*c multithreaded application has memory leak
Hi there,
I posted this message a week ago in OCI section, nobody answer me.
I am really curious if my application has a bug or the pro*c has a bug.
Anyone can compile the sample code and test it easily.
I made multithreaded application which queries dynamic SQL, it works.
But the memory leaks when i query the SQL statement.
The more memory leaks, the more i query the SQL statement, even same SQL
statement.
I check it with top, shell command.
My machine is SUN E450, Solaris 8. Oracle 9.2.0.1
Compiler : gcc (GCC) 3.2.2
I changed source code which is from
$(ORACLE_HOME)/precomp/demo/proc/sample10.pc
the sample10 doesn't need to be multithreaded. But i think it has to work
correctly if i changed it to multithreaded application.
the make file and source code will be placed below.
I have to figure out the problem.
Please help
Thanks in advance,
the make file is below
HOME = /user/jkku
ORA = $(ORACLE_HOME)
CC = gcc
PROC = proc
LC_INCL = -I$(HOME)/work/dbmss/libs/include
lc_incl = include=$(HOME)/work/dbmss/libs/include
SYS_INCL =
sys_incl =
ORA_INCL = -I. \
-I$(ORA)/precomp/public \
-I$(ORA)/rdbms/public \
-I$(ORA)/rdbms/demo \
-I$(ORA)/rdbms/pbsql/public \
-I$(ORA)/network/public \
-DSLMXMX_ENABLE -DSLTS_ENABLE -D_SVID_GETTOD
INCLUDES = $(LC_INCL) $(SYS_INCL) $(ORA_INCL)
includes = $(lc_incl) $(sys_incl)
LC_LIBS =
SYS_LIBS = -lpthread -lsocket -lnsl -lrt
ORA_LIBS = -L$(ORA)/lib/ -lclntsh
LIBS = $(LC_LIBS) $(SYS_LIBS) $(ORA_LIBS)
# Define C Compiler flags
CFLAGS += -D_Solaris64_ -m64
CFLAGS += -g -D_REENTRANT
# Define pro*c Compiler flags
PROCFLAGS += THREADS=YES
PROCFLAGS += CPOOL=YES
# Our object files
PRECOMPS = sample10.c
OBJS = sample10.o
.SUFFIXES: .o .c .pc
.c.o:
$(CC) -c $(CFLAGS) $(INCLUDES) $*.c
.pc.c:
$(PROC) $(PROCFLAGS) $(includes) $*.pc $*.c
all: sample10
sample10: $(PRECOMPS) $(OBJS)
$(CC) $(CFLAGS) -o sample10 $(OBJS) $(LIBS)
clean:
rm -rf *.o sample10 sample10.c
the source code is below which i changed the oracle sample10.pc to
multithreaded application.
Sample Program 10: Dynamic SQL Method 4
This program connects you to ORACLE using your username and
password, then prompts you for a SQL statement. You can enter
any legal SQL statement. Use regular SQL syntax, not embedded SQL.
Your statement will be processed. If it is a query, the rows
fetched are displayed.
You can enter multi-line statements. The limit is 1023 characters.
This sample program only processes up to MAX_ITEMS bind variables and
MAX_ITEMS select-list items. MAX_ITEMS is #defined to be 40.
#include <stdio.h>
#include <string.h>
#include <setjmp.h>
#include <sqlda.h>
#include <stdlib.h>
#include <sqlcpr.h>
/* Maximum number of select-list items or bind variables. */
#define MAX_ITEMS 40
/* Maximum lengths of the names of the
select-list items or indicator variables. */
#define MAX_VNAME_LEN 30
#define MAX_INAME_LEN 30
#ifndef NULL
#define NULL 0
#endif
/* Prototypes */
#if defined(__STDC__)
void sql_error(void);
int oracle_connect(void);
int alloc_descriptors(int, int, int);
int get_dyn_statement(void);
void set_bind_variables(void);
void process_select_list(void);
void help(void);
#else
void sql_error(/*_ void _*/);
int oracle_connect(/*_ void _*/);
int alloc_descriptors(/*_ int, int, int _*/);
int get_dyn_statement(/* void _*/);
void set_bind_variables(/*_ void -*/);
void process_select_list(/*_ void _*/);
void help(/*_ void _*/);
#endif
char *dml_commands[] = {"SELECT", "select", "INSERT", "insert",
"UPDATE", "update", "DELETE", "delete"};
EXEC SQL INCLUDE sqlda;
EXEC SQL INCLUDE sqlca;
EXEC SQL BEGIN DECLARE SECTION;
char dyn_statement[1024];
EXEC SQL VAR dyn_statement IS STRING(1024);
EXEC SQL END DECLARE SECTION;
EXEC ORACLE OPTION (ORACA=YES);
EXEC ORACLE OPTION (RELEASE_CURSOR=YES);
SQLDA *bind_dp;
SQLDA *select_dp;
/* Define a buffer to hold longjmp state info. */
jmp_buf jmp_continue;
char *db_uid="dbmuser/dbmuser@dbmdb";
sql_context ctx;
int err_sql;
enum{
SQL_SUCC=0,
SQL_ERR,
SQL_NOTFOUND,
SQL_UNIQUE,
SQL_DISCONNECT,
SQL_NOTNULL
int main()
int i;
EXEC SQL ENABLE THREADS;
EXEC SQL WHENEVER SQLERROR DO sql_error();
EXEC SQL WHENEVER NOT FOUND DO sql_not_found();
/* Connect to the database. */
if (connect_database() < 0)
exit(1);
EXEC SQL CONTEXT USE :ctx;
/* Process SQL statements. */
for (;;)
/* Allocate memory for the select and bind descriptors. */
if (alloc_descriptors(MAX_ITEMS, MAX_VNAME_LEN, NAME_LEN) != 0)
exit(1);
(void) setjmp(jmp_continue);
/* Get the statement. Break on "exit". */
if (get_dyn_statement() != 0)
break;
EXEC SQL PREPARE S FROM :dyn_statement;
EXEC SQL DECLARE C CURSOR FOR S;
/* Set the bind variables for any placeholders in the
SQL statement. */
set_bind_variables();
/* Open the cursor and execute the statement.
* If the statement is not a query (SELECT), the
* statement processing is completed after the
* OPEN.
EXEC SQL OPEN C USING DESCRIPTOR bind_dp;
/* Call the function that processes the select-list.
* If the statement is not a query, this function
* just returns, doing nothing.
process_select_list();
/* Tell user how many rows processed. */
for (i = 0; i < 8; i++)
if (strncmp(dyn_statement, dml_commands, 6) == 0)
printf("\n\n%d row%c processed.\n", sqlca.sqlerrd[2], sqlca.sqlerrd[2] == 1 ? '\0' : 's');
break;
/* Close the cursor. */
EXEC SQL CLOSE C;
/* When done, free the memory allocated for pointers in the bind and
select descriptors. */
for (i = 0; i < MAX_ITEMS; i++)
if (bind_dp->V != (char *) 0)
free(bind_dp->V);
free(bind_dp->I); /* MAX_ITEMS were allocated. */
if (select_dp->V != (char *) 0)
free(select_dp->V);
free(select_dp->I); /* MAX_ITEMS were allocated. */
/* Free space used by the descriptors themselves. */
SQLSQLDAFree(ctx, bind_dp);
SQLSQLDAFree(ctx, select_dp);
} /* end of for(;;) statement-processing loop */
disconnect_database();
EXEC SQL WHENEVER SQLERROR CONTINUE;
EXEC SQL COMMIT WORK RELEASE;
puts("\nHave a good day!\n");
return;
* Allocate the BIND and SELECT descriptors using sqlald().
* Also allocate the pointers to indicator variables
* in each descriptor. The pointers to the actual bind
* variables and the select-list items are realloc'ed in
* the set_bind_variables() or process_select_list()
* routines. This routine allocates 1 byte for select_dp->V
* and bind_dp->V, so the realloc will work correctly.
alloc_descriptors(size, max_vname_len, max_iname_len)
int size;
int max_vname_len;
int max_iname_len;
int i;
* The first sqlald parameter determines the maximum number of
* array elements in each variable in the descriptor. In
* other words, it determines the maximum number of bind
* variables or select-list items in the SQL statement.
* The second parameter determines the maximum length of
* strings used to hold the names of select-list items
* or placeholders. The maximum length of column
* names in ORACLE is 30, but you can allocate more or less
* as needed.
* The third parameter determines the maximum length of
* strings used to hold the names of any indicator
* variables. To follow ORACLE standards, the maximum
* length of these should be 30. But, you can allocate
* more or less as needed.
if ((bind_dp =
SQLSQLDAAlloc(ctx, size, max_vname_len, max_iname_len)) ==
(SQLDA *) 0)
fprintf(stderr,
"Cannot allocate memory for bind descriptor.");
return -1; /* Have to exit in this case. */
if ((select_dp =
SQLSQLDAAlloc(ctx, size, max_vname_len, max_iname_len)) == (SQLDA *)
0)
fprintf(stderr,
"Cannot allocate memory for select descriptor.");
return -1;
select_dp->N = MAX_ITEMS;
/* Allocate the pointers to the indicator variables, and the
actual data. */
for (i = 0; i < MAX_ITEMS; i++) {
bind_dp->I = (short *) malloc(sizeof (short));
select_dp->I = (short *) malloc(sizeof(short));
bind_dp->V = (char *) malloc(1);
select_dp->V = (char *) malloc(1);
return 0;
int get_dyn_statement()
char *cp, linebuf[256];
int iter, plsql;
for (plsql = 0, iter = 1; ;)
if (iter == 1)
printf("\nSQL> ");
dyn_statement[0] = '\0';
fgets(linebuf, sizeof linebuf, stdin);
cp = strrchr(linebuf, '\n');
if (cp && cp != linebuf)
*cp = ' ';
else if (cp == linebuf)
continue;
if ((strncmp(linebuf, "EXIT", 4) == 0) ||
(strncmp(linebuf, "exit", 4) == 0))
return -1;
else if (linebuf[0] == '?' ||
(strncmp(linebuf, "HELP", 4) == 0) ||
(strncmp(linebuf, "help", 4) == 0))
help();
iter = 1;
continue;
if (strstr(linebuf, "BEGIN") ||
(strstr(linebuf, "begin")))
plsql = 1;
strcat(dyn_statement, linebuf);
if ((plsql && (cp = strrchr(dyn_statement, '/'))) ||
(!plsql && (cp = strrchr(dyn_statement, ';'))))
*cp = '\0';
break;
else
iter++;
printf("%3d ", iter);
return 0;
void set_bind_variables()
int i, n;
char bind_var[64];
/* Describe any bind variables (input host variables) */
EXEC SQL WHENEVER SQLERROR DO sql_error();
bind_dp->N = MAX_ITEMS; /* Initialize count of array elements. */
EXEC SQL DESCRIBE BIND VARIABLES FOR S INTO bind_dp;
/* If F is negative, there were more bind variables
than originally allocated by sqlald(). */
if (bind_dp->F < 0)
printf ("\nToo many bind variables (%d), maximum is %d\n.",
-bind_dp->F, MAX_ITEMS);
return;
/* Set the maximum number of array elements in the
descriptor to the number found. */
bind_dp->N = bind_dp->F;
/* Get the value of each bind variable as a
* character string.
* C contains the length of the bind variable
* name used in the SQL statement.
* S contains the actual name of the bind variable
* used in the SQL statement.
* L will contain the length of the data value
* entered.
* V will contain the address of the data value
* entered.
* T is always set to 1 because in this sample program
* data values for all bind variables are entered
* as character strings.
* ORACLE converts to the table value from CHAR.
* I will point to the indicator value, which is
* set to -1 when the bind variable value is "null".
for (i = 0; i < bind_dp->F; i++)
printf ("\nEnter value for bind variable %.*s: ",
(int)bind_dp->C, bind_dp->S);
fgets(bind_var, sizeof bind_var, stdin);
/* Get length and remove the new line character. */
n = strlen(bind_var) - 1;
/* Set it in the descriptor. */
bind_dp->L = n;
/* (re-)allocate the buffer for the value.
sqlald() reserves a pointer location for
V but does not allocate the full space for
the pointer. */
bind_dp->V = (char *) realloc(bind_dp->V, (bind_dp->L + 1));
/* And copy it in. */
strncpy(bind_dp->V, bind_var, n);
/* Set the indicator variable's value. */
if ((strncmp(bind_dp->V, "NULL", 4) == 0) ||
(strncmp(bind_dp->V, "null", 4) == 0))
*bind_dp->I = -1;
else
*bind_dp->I = 0;
/* Set the bind datatype to 1 for CHAR. */
bind_dp->T = 1;
return;
void process_select_list()
int i, null_ok, precision, scale;
if ((strncmp(dyn_statement, "SELECT", 6) != 0) &&
(strncmp(dyn_statement, "select", 6) != 0))
select_dp->F = 0;
return;
/* If the SQL statement is a SELECT, describe the
select-list items. The DESCRIBE function returns
their names, datatypes, lengths (including precision
and scale), and NULL/NOT NULL statuses. */
select_dp->N = MAX_ITEMS;
EXEC SQL DESCRIBE SELECT LIST FOR S INTO select_dp;
/* If F is negative, there were more select-list
items than originally allocated by sqlald(). */
if (select_dp->F < 0)
printf ("\nToo many select-list items (%d), maximum is %d\n",
-(select_dp->F), MAX_ITEMS);
return;
/* Set the maximum number of array elements in the
descriptor to the number found. */
select_dp->N = select_dp->F;
/* Allocate storage for each select-list item.
sqlprc() is used to extract precision and scale
from the length (select_dp->L).
sqlnul() is used to reset the high-order bit of
the datatype and to check whether the column
is NOT NULL.
CHAR datatypes have length, but zero precision and
scale. The length is defined at CREATE time.
NUMBER datatypes have precision and scale only if
defined at CREATE time. If the column
definition was just NUMBER, the precision
and scale are zero, and you must allocate
the required maximum length.
DATE datatypes return a length of 7 if the default
format is used. This should be increased to
9 to store the actual date character string.
If you use the TO_CHAR function, the maximum
length could be 75, but will probably be less
(you can see the effects of this in SQL*Plus).
ROWID datatype always returns a fixed length of 18 if
coerced to CHAR.
LONG and
LONG RAW datatypes return a length of 0 (zero),
so you need to set a maximum. In this example,
it is 240 characters.
printf ("\n");
for (i = 0; i < select_dp->F; i++)
char title[MAX_VNAME_LEN];
/* Turn off high-order bit of datatype (in this example,
it does not matter if the column is NOT NULL). */
sqlnul ((unsigned short *)&(select_dp->T), (unsigned short
*)&(select_dp->T), &null_ok);
switch (select_dp->T)
case 1 : /* CHAR datatype: no change in length
needed, except possibly for TO_CHAR
conversions (not handled here). */
break;
case 2 : /* NUMBER datatype: use sqlprc() to
extract precision and scale. */
sqlprc ((unsigned int *)&(select_dp->L), &precision,
&scale);
/* Allow for maximum size of NUMBER. */
if (precision == 0) precision = 40;
/* Also allow for decimal point and
possible sign. */
/* convert NUMBER datatype to FLOAT if scale > 0,
INT otherwise. */
if (scale > 0)
select_dp->L = sizeof(float);
else
select_dp->L = sizeof(int);
break;
case 8 : /* LONG datatype */
select_dp->L = 240;
break;
case 11 : /* ROWID datatype */
case 104 : /* Universal ROWID datatype */
select_dp->L = 18;
break;
case 12 : /* DATE datatype */
select_dp->L = 9;
break;
case 23 : /* RAW datatype */
break;
case 24 : /* LONG RAW datatype */
select_dp->L = 240;
break;
/* Allocate space for the select-list data values.
sqlald() reserves a pointer location for
V but does not allocate the full space for
the pointer. */
if (select_dp->T != 2)
select_dp->V = (char *) realloc(select_dp->V,
select_dp->L + 1);
else
select_dp->V = (char *) realloc(select_dp->V,
select_dp->L);
/* Print column headings, right-justifying number
column headings. */
/* Copy to temporary buffer in case name is null-terminated */
memset(title, ' ', MAX_VNAME_LEN);
strncpy(title, select_dp->S, select_dp->C);
if (select_dp->T == 2)
if (scale > 0)
printf ("%.*s ", select_dp->L+3, title);
else
printf ("%.*s ", select_dp->L, title);
else
printf("%-.*s ", select_dp->L, title);
/* Coerce ALL datatypes except for LONG RAW and NUMBER to
character. */
if (select_dp->T != 24 && select_dp->T != 2)
select_dp->T = 1;
/* Coerce the datatypes of NUMBERs to float or int depending on
the scale. */
if (select_dp->T == 2)
if (scale > 0)
select_dp->T = 4; /* float */
else
select_dp->T = 3; /* int */
printf ("\n\n");
/* FETCH each row selected and print the column values. */
EXEC SQL WHENEVER NOT FOUND GOTO end_select_loop;
for (;;)
EXEC SQL FETCH C USING DESCRIPTOR select_dp;
/* Since each variable returned has been coerced to a
character string, int, or float very little processing
is required here. This routine just prints out the
values on the terminal. */
for (i = 0; i < select_dp->F; i++)
if (*select_dp->I < 0)
if (select_dp->T == 4)
printf ("%-*c ",(int)select_dp->L+3, ' ');
else
printf ("%-*c ",(int)select_dp->L, ' ');
else
if (select_dp->T == 3) /* int datatype */
printf ("%*d ", (int)select_dp->L,
*(int *)select_dp->V);
else if (select_dp->T == 4) /* float datatype */
printf ("%*.2f ", (int)select_dp->L,
*(float *)select_dp->V);
else /* character string */
printf ("%-*.*s ", (int)select_dp->L,
(int)select_dp->L, select_dp->V);
printf ("\n");
end_select_loop:
return;
void help()
puts("\n\nEnter a SQL statement or a PL/SQL block at the SQL> prompt.");
puts("Statements can be continued over several lines, except");
puts("within string literals.");
puts("Terminate a SQL statement with a semicolon.");
puts("Terminate a PL/SQL block (which can contain embedded
semicolons)");
puts("with a slash (/).");
puts("Typing \"exit\" (no semicolon needed) exits the program.");
puts("You typed \"?\" or \"help\" to get this message.\n\n");
int connect_database()
err_sql = SQL_SUCC;
EXEC SQL WHENEVER SQLERROR DO sql_error();
EXEC SQL WHENEVER NOT FOUND DO sql_not_found();
EXEC SQL CONTEXT ALLOCATE :ctx;
EXEC SQL CONTEXT USE :ctx;
EXEC SQL CONNECT :db_uid;
if(err_sql != SQL_SUCC){
printf("err => connect database(ctx:%ld, uid:%s) failed!\n", ctx, db_uid);
return -1;
return 1;
int disconnect_database()
err_sql = SQL_SUCC;
EXEC SQL WHENEVER SQLERROR DO sql_error();
EXEC SQL WHENEVER NOT FOUND DO sql_not_found();
EXEC SQL CONTEXT USE :ctx;
EXEC SQL COMMIT WORK RELEASE;
EXEC SQL CONTEXT FREE:ctx;
return 1;
void sql_error()
printf("err => %.*s", sqlca.sqlerrm.sqlerrml, sqlca.sqlerrm.sqlerrmc);
printf("in \"%.*s...\'\n", oraca.orastxt.orastxtl, oraca.orastxt.orastxtc);
printf("on line %d of %.*s.\n\n", oraca.oraslnr, oraca.orasfnm.orasfnml,
oraca.orasfnm.orasfnmc);
switch(sqlca.sqlcode) {
case -1: /* unique constraint violated */
err_sql = SQL_UNIQUE;
break;
case -1012: /* not logged on */
case -1089:
case -3133:
case -1041:
case -3114:
case -3113:
/* �6�Ŭ�� shutdown�ǰų� �α��� ���°� �ƴҶ� ��b�� �õ� */
/* immediate shutdown in progress - no operations are permitted */
/* end-of-file on communication channel */
/* internal error. hostdef extension doesn't exist */
err_sql = SQL_DISCONNECT;
break;
case -1400:
err_sql = SQL_NOTNULL;
break;
default:
err_sql = SQL_ERR;
break;
EXEC SQL CONTEXT USE :ctx;
EXEC SQL WHENEVER SQLERROR CONTINUE;
EXEC SQL ROLLBACK WORK;
void sql_not_found()
err_sql = SQL_NOTFOUND;Hi Jane,
What version of Berkeley DB XML are you using?
What is your operating system and your hardware platform?
For how long have been the application running?
What is your current container size?
What's set for EnvironmentConfig.setThreaded?
Do you know if containers have previously not been closed correctly?
Can you please post the entire error output?
What's the JDK version, 1.4 or 1.5?
Thanks,
Bogdan
Maybe you are looking for
-
Upgrading Windows 8 to 8.1 [Native VHD Boot]
Hey folks, I've got Windows 8 RTM running in a native VHD on my Dell Latitude E6430. I just tried to initiate the upgrade to Windows 8.1 by extracting the Windows 8.1 ISO with 7-Zip, and launching setup.exe from the extracted folder. Unfortunately, w
-
Problems with ESS in "Career and Jobs" option
Hi In the ESS has problem in Career option (show in the following links) http://img517.imageshack.us/img517/4193/careerjob1.jpg http://img200.imageshack.us/img200/4583/careerjob2.jpg My main target actives the "other options" in my ESS only appear t
-
Can't pair SW2 with Asus Padfone 2
As the title said really. I have done everything as the instructed. Yet I can't even make a pair happen via bluetooth. All it ever show up is "Can't comunicate with SmartWatch 2" any help will be much appreciated...... and no I do not wish to root my
-
Why Does My MacBook Pro Keep forcing a shut down?
Whenever I shut down my macbook pro MANUALLY it waits a little and then brings up the "you must restart your computer" screen (the one in diff languages). How do I stop this? Is this hurting my computer? I have 2 external hardrrives (one FW), an Mbox
-
I just started using the Zosh app which allows for signing on the iPad/iPhone. However when I receive an email back from them with an attachment, it shows up in my inbox as having an attachment, and can be seen on my iPhone just fine, but on the iPad