Unused packages in import statement

Guyz,
Can anyone throw some light on this ?
Does using a lot of unused packages in import statement of a jsp affects its performance in terms of page loading ?
Thanks.

I have just found the answer for my question in another forum.
Please visit:
http://saloon.javaranch.com/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic&f=15&t=000240
Thanks.

Similar Messages

A problem from "import" statement

When I was doing some test on "package" and "import" statement, I had a problem.
1 I compiled one class:
package com.sheng.population;
public class A {
     public static int sum (int k, int l) {
          return (k+l);
2 I tried to call the method 'sum' in A:
import com.sheng.population.*;
public class B {
     public static void main(String[] args){
          int i=9;
          int j=100;
          int k = A.sum(i, j);
          System.out.println(k);
Then I got the error message:
"B.java:7: cannot access A
bad class file: E:\newjava\analysis\LDmeasure\A.java
file does not contain class A"
Only after I changed the import statement to "import com.sheng.population.A;" , then it worked.
I just do not know why the '.*' does not work?
Thanks

Let's say your directory structure is "e:\newjava\com\sheng\population\A.class" and "e:\newjava\analysis\LDmeasure\A.java"
If your Classpath is .;e:\newjava and when you compile, your current directory is e:\newjava\analysis\LDmeasure then you have A.java and A.class in your Classpath. When you use "import com.sheng.population.*;" the compiler does not know you mean com.sheng.population.A. The compiler finds A.java and thinks it is the A class that the B class needs. When it tries to compile A.java it finds the class name is com.sheng.population.A which causes the error. When you use "import com.sheng.population.A;" the compiler does not try to use A.java.
If you are keeping the source code in a different directory from the compiled classes, then you should not have the source code in the Classpath. So, if you make sure the current directory is not e:\newjava\analysis\LDmeasure then it should compile.

Import statement reports 'package does not exist'

I am seeing another odd error. I'm working on learning how to read and write to text files, and I have 2 errors reported, but one is obviously caused by the other. My package is labeled as such (copy>paste of package line):
package michaelchristopherp4db;
and the import line is this (copy>paste again):
import michaelchristopherp4db.ProductRecord;
However, Netbeans looks at the import and flags it red, saying package michaelchristopherp4db does not exist. this caused my line:
ProductRecord product = new ProductRecord();
to also be flagged in red as it cannot find the ProductRecord class. However, it has no problems with any of the product.get* method calls. Thank you in advance for any ideas or input.
here is the full code of the file reporting the errors.
* To change this template, choose Tools | Templates
* and open the template in the editor.
package michaelchristopherp4db2;
import java.io.File;
import java.io.FileNotFoundException;
import java.lang.IllegalStateException;
import java.lang.SecurityException;
import java.util.NoSuchElementException;
import java.util.Formatter;
import java.util.FormatterClosedException;
import java.util.Scanner;
import michaelchristopherp4db.ProductRecord;
/* @author info
public class readTxt
    private Scanner txtfile;
    private Formatter wishList;
    private Formatter giftIdeas;
    private Formatter priceError;
    //let user open file
    public void openFile()
    {//open method openFile
        try
        {//open try block
            priceError = new Formatter("priceerror.txt");//open object for items with invalid prices
            giftIdeas = new Formatter("giftideas.txt");//open object for gift ideas
            wishList = new Formatter("wishlist.txt");//open object for wish list
            txtfile = new Scanner(new File("products.txt"));//tell the compiler which file to use for input
        }//close try block
        catch (FileNotFoundException fileNotFoundException)
        {//open file not found catch block
            System.err.println("Error opening or creating file.");
            System.exit(1);
        }//close file not found catch block
        catch ( SecurityException securityException )
        {//start catch for SecurityException
            System.err.println("File Write access is denied.");
            System.exit(1);//END PROGRAM
        }//end catch
    }//close openFile method
    public void readProducts()
    {//open readProducts method
        ProductRecord product = new ProductRecord();//create object to hold read data
        //print headers for for output columns
        System.out.printf("%-10s%-12s%10s\n", "Product ID", "Product Name", "Price");
        try //read records from the file
        {//open try block
            while (txtfile.hasNext())
            {//open while
                product.setproductID(txtfile.nextInt());//get productID
                product.setproductName(txtfile.next());//get product name
                product.setproductPrice(txtfile.nextDouble());//get product price
                //print collected product details
                System.out.printf("%-10d%-12s%10.2f\n", product.getproductID(),
                        product.getproductName(), product.getproductPrice());
                if (product.getproductPrice()>50.0)
                {//open if to store items $50 or more to wishlist.txt
                    wishList.format("%-10d%-12s%10.2f\n", product.getproductID(),
                            product.getproductName(), product.getproductPrice());
                }//close if $50 or greater
                else if (product.getproductPrice()<0.0)
                {//open if less than zero
                    priceError.format("%-10d%-12s%10.2f\n", product.getproductID(),
                            product.getproductName(), product.getproductPrice());
                }//close if less than zero
                else
                {//open else for gift ideas from $0 to $50
                    giftIdeas.format("%-10d%-12s%10.2f\n", product.getproductID(),
                            product.getproductName(), product.getproductPrice());
                }//close else for gift ideas
            }//close while
        }//close try block
        catch (NoSuchElementException elementException)
        {//open no such element exception catch
            System.err.println("File improperly formed.");
            txtfile.close();//close text file
            System.exit(1);
        }//close no such element exception catch
        catch (IllegalStateException stateException)
        {//open illegal state exception catch
            System.err.println("Error reading from file.");
            System.exit(1);
        }//close illegal state exception catch
    }//close readProducts method
    //close file and end application
    public void closeFile()
    {//open closeFile method
        if (txtfile != null)
            txtfile.close();//close file
    }//close closeFile method
}//end application readTxtAnd the code at the top of the class I am trying to import (so you can see the package I am trying to import)
* To change this template, choose Tools | Templates
* and open the template in the editor.
package michaelchristopherp4db;
* @author
public class ProductRecord {

I am embarrassed to admit this, but I am completely lost on the last question.. I have no clue wether it is a convenience for development or a dependancy, as I have not learned those terms or distinctions yet. For now I copied the ProductRecord file into my new project folder and renamed it's project line to match the new project name. However, while that eliminated the package does not exist error, and netbeans reports no errors now, when I run the program it does not write the new files. I have made some modifications to the code tryiing to get it to write properly but so far no luck in makingit work. Here is the current version of the file not running right.
* To change this template, choose Tools | Templates
* and open the template in the editor.
package michaelchristopherp4db2;
import java.io.File;
import java.io.FileNotFoundException;
import java.lang.IllegalStateException;
import java.lang.SecurityException;
import java.util.NoSuchElementException;
import java.util.Formatter;
import java.util.FormatterClosedException;
import java.util.Scanner;
/* @author
*   Michael Christopher
*   IT215-1004D-03
*   December 30, 2010
*   Phase 4 DB 2
public class readTxt
    private Scanner txtfile;
    private Formatter wishList;
    private Formatter giftIdeas;
    private Formatter priceError;
    //let user open file
    public void openFile()
    {//open method openFile
        try
        {//open try block
            priceError = new Formatter("priceerror.txt");//open object for items with invalid prices
            giftIdeas = new Formatter("giftideas.txt");//open object for gift ideas
            wishList = new Formatter("wishlist.txt");//open object for wish list
            txtfile = new Scanner(new File("products.txt"));//tell the compiler which file to use for input
        }//close try block
        catch (FileNotFoundException fileNotFoundException)
        {//open file not found catch block
            System.err.println("Error opening or creating file.");
            System.exit(1);
        }//close file not found catch block
        catch ( SecurityException securityException )
        {//start catch for SecurityException
            System.err.println("File Write access is denied.");
            System.exit(1);//END PROGRAM
        }//end catch
    }//close openFile method
    public void readProducts()
    {//open readProducts method
        ProductRecord product = new ProductRecord();//create object to hold read data
        //print headers for for output columns
        wishList.format("%-10s%-12s%10s\n", "Product ID", "Product Name", "Price");
        giftIdeas.format("%-10s%-12s%10s\n", "Product ID", "Product Name", "Price");
        priceError.format("%-10s%-12s%10s\n", "Product ID", "Product Name", "Price");
        try //read records from the file
        {//open try block
            while (txtfile.hasNext())
            {//open while
                product.setproductID(txtfile.nextInt());//get productID
                product.setproductName(txtfile.next());//get product name
                product.setproductPrice(txtfile.nextDouble());//get product price
                if (product.getproductPrice()>50.0)
                {//open if to store items $50 or more to wishlist.txt
                    wishList.format("%-10d%-12s%10.2f\n", product.getproductID(),
                            product.getproductName(), product.getproductPrice());
                }//close if $50 or greater
                else if (product.getproductPrice()<0.0)
                {//open if less than zero
                    priceError.format("%-10d%-12s%10.2f\n", product.getproductID(),
                            product.getproductName(), product.getproductPrice());
                }//close if less than zero
                else
                {//open else for gift ideas from $0 to $50
                    giftIdeas.format("%-10d%-12s%10.2f\n", product.getproductID(),
                            product.getproductName(), product.getproductPrice());
                }//close else for gift ideas
            }//close while
        }//close try block
        catch (NoSuchElementException elementException)
        {//open no such element exception catch
            System.err.println("File improperly formed.");
            txtfile.close();//close text file
            System.exit(1);
        }//close no such element exception catch
        catch (IllegalStateException stateException)
        {//open illegal state exception catch
            System.err.println("Error reading from file.");
            System.exit(1);
        }//close illegal state exception catch
    }//close readProducts method
    //close file and end application
    public void closeFile()
    {//open closeFile method
        if (txtfile != null)
            txtfile.close();//close file
    }//close closeFile method
}//end application readTxtwith the System.out.printf lines in the ReadProducts method it would properly print to screen all of the elements in the products.txt file, it is not outputting to the other .txt files at all. I will be exploring the closeFile method in case the error is due to not closing all of the files in that method, but does anyone else see what might cause it not to output the data to the appropriate .txt files?

Package scope and import statements

Hi everubody,
I'm studing a code: foo.java written by sb. else. In the code, I have:
package com.dir1.dir2.dir3;
import com.dir1.dir4.code1;
import com.dir1.dir5.code2;
The code: foo.java exists in the directory: com/dir1/dir2/dir3 as expected. However, in the import statements, there is NO dir4 and dir5 under com/dir1? Shouldn't the import statements be relative to the directory of package?
Guess I'm missing a point here... Any help is greatly apprecited.

When you import:
import co.mycompany.my.MyClass
then MyClass should reside in the directory:
co/mycompany/my, right?Right. Somewhere in the classpath there would have to be that directory structure. Again, that could be an actual directory name, or a path name in a Jar.
Then if the code: foo.java resides in the directory:
com/dir2/dir3 with the:
package com.dir1.dir2.dir3;
How the compiler and JVM finds the code MyClass
(which you imported in foo.java)?Thru the magic known as the classpath.

Package/Import statements - javac gives errors while Netbeans does not

I do not know why, but when I compile/run my code with the statements
package TavisProject;
import TavisProject.LabelAndButtonFrame;
in Netbeans, everything works properly as it should. However, if I try to compile the SAME files with javac at the cmd line, I get the errors:
C:\FinalProject\src\TavisProject>javac Main.java
Main.java:22: cannot find symbol
symbol : class LabelAndButtonFrame
location: class TavisProject.Main
LabelAndButtonFrame labelAndButtonFrame = new LabelAndButtonFram
e(); // Instantiates/calls labelAndButtonFrame
^
Main.java:22: cannot find symbol
symbol : class LabelAndButtonFrame
location: class TavisProject.Main
LabelAndButtonFrame labelAndButtonFrame = new LabelAndButtonFram
e(); // Instantiates/calls labelAndButtonFrame
^
2 errors
Also, if you comment out the statements in both files, everything compiles fine with javac. Also, please note that LabelAndButtonFrame.java is in the same folder as Main.java.
I'm trying to get a batch file to work properly that will compile/create javadoc, but I can't get it to work without figuring
out what the deal is with those package/import statments causing problems.
Thanks,
Tavis
The main code is as follows:
package TavisProject;
import TavisProject.LabelAndButtonFrame;
import javax.swing.JFrame;
* @author Tavis Curry
* @version 1.0
* This Class is called MainMethod. It instantiates/calls labelAndButtonFrame.
* Uses javax.swing.JFrame
public class Main
       * Main method
          * This method will call labeAndButtonFrame, set the default close op,
          * set the size of the jframe, and set the jframe to visible
        public static void main(String args[]){
                LabelAndButtonFrame labelAndButtonFrame = new LabelAndButtonFrame(); // Instantiates/calls labelAndButtonFrame
          labelAndButtonFrame.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE ); // LabelAndButtonFrame will Exit when the X-button is clicked
                labelAndButtonFrame.setSize( 550, 70 ); // Sets frame size - width by height
                labelAndButtonFrame.setVisible(true); // Shows LabelAndButtonFrame
     } // End main method
} // End class LabelAndButtonFrameMessage was edited by:
TC10284

Thanks much. That worked.
I had EVERYTHING working except this little thing.
I'm a little confused on why it makes a difference if
I set this however. Why can the compiler not find the
files if they're in the same dir?Because it doesn't find files - it finds classes.
The fact that it can use directories to organize the hierarchy is misleading. That is an easy convention but it doesn't alter the fact that it uses the class path itself along with other rules to find classes (not files.)
>
Also, now that I have to set the classpath, how would
I get this to work inside a batch file that uses env.
variables to locate the base project?
Both the java compiler and the java vm tools support a command line option which allows you to fully specify the class path.

Import Statement Different ways to refer ???

Dear Friends,
Can any one help me the difference between the usage of import statement....
1. using import statement
2. using the class directly
that is,
for example ;
1. import java.util.Date;
Date dt = new Date();
2. java.util.Date dt = new java.util.Date();
what's the difference between two reference of Date class...is there any meaning beyond this ?????
Regards,
V.Prasanna

what's the difference between two reference of Date
class...is there any meaning beyond this ?????there is no difference once the code is compiled - the compiler resolves single class names to their fully-qualified names (ie with the package prefix) and that appears in the .class file constant pool
before compilation then my opinion is that having all the imports at the top of the file is good practice because you can see what is being used easily

Import Statement Error

Does anyone know what is wrong with these import statement?
import Reduction;
import Mapper;
import ApplyObj;
import ApplyObjUnary;
import java.lang.String;
public class Driver{
public static Driver me = new Driver();
public static void main(String[] args){
int i;
I places all my *.java file in the same directory as Driver.java
But when i try to compile Driver.java, it says :-
C:\assignment1>javac Driver.java
Driver.java:10: '.' expected
import Reduction;
^
Driver.java:11: '.' expected
import Mapper;
^
Driver.java:12: '.' expected
import ApplyObj;
^
Driver.java:13: '.' expected
import ApplyObjUnary;
^
4 errors
I set my class path as
C:\>SET CLASSPATH = .;C:\j2sdk1.4.0_01;c:\assignment1
Apparently, the current directory has been set and my assignment1 directory has been set.
Did i miss out anything? Why does it can't recognize the existence of other class file in the same directory?
thanks.

You don't need to import classes that are in the default package (i.e. you didn't put them in a package). And in Java 1.4, you can't import them. Just remove the import statements, you shouldn't need them.

Import statement is not working

hi everybody,
I have a directory under which I have a number of sub-directories. Lets call this directory "parent_directory". under this directory I have another directory called "child_1". Under "child_1" I have another subdirectory called "child_2". Now I have a code in child_2 that has the following statement:
import program_1;
//this is a program present in the parent directory. lets call it
//program_1.java
when I am compiling I am getting an error saying:
program_2.java:28: '.' expected
import program_1;
^
1 error
program_2.java is the program present in child_2 in which I have included the import statement.
If I change the ";" to "." then again error appears as the import statement only needs the name of the class and doesnot need the extension.
I will be very grateful to you if you could please suggest me a way around this.

This questions belongs in the "New to Java" forum ...
sigh
Anyways, import works on package names with trailing * or full qualified class names, e.g.import mypackage1.*; // imports all classes in mypackage1
import mypackage2.MyClass2; // imports MyClass2 from mypackage2So instead of import program_1; you need to do
1. ensure that program_1 is in some package
2. ensure that your directory structure mirrors your package structure (same names!)
3. ensure that your CLASSPATH is either not set at all or points to the parent dir of your topmost package
Example:
Directory structure:C:\tmp\java\top\
C:\tmp\java\top\MyClass1.java
C:\tmp\java\top\bottom\
C:\tmp\java\top\bottom\MyClass2.java
CLASSPATH=".;<java install dir>\jre\lib\rt.jar;C:\tmp\java"Source for MyClass1.java:package top;
public class MyClass1 {
}Source for MyClass2.java:package top.bottom;
import top.MyClass1;
public class MyClass2 {
private MyClass1 myClass1;
}

Import Statement without ID Specification

There is an import statement
IMPORT tab g_acc_tab FROM MEMORY.
While UCChecking it.. it saying that
import statement without id specification is only used for the sake of r/2 ......
Can i Comment it ? If so won't my application go into dump while running on 6.0cc???

It has to do with packages. Most java classes are in a package, the name of which must conform to its place on the filesystem relative to the classpath. By that I mean that if you have com.mystuff.One.java, it must be in a folder com/mystuff where com is located somewhere in the classpath.
What you've done is a little different. I'm assuming a couple of things:
1. you have no package declaration at the top of one.java or two.java
2. you have the current directory "." in your classpath.
Java has the concept of the "default package", which covers classes without a declared package, and in your case is the current directory.
So when you're in c:\sourcefolder and run the compiler, then "."="c:\sourcefolder", and that directory is part of the default package. No import statements are necessary for classes that are in the same package. This is why two.java can call methods in one.java without an import statement.
When you run your jsp, the "current directory" part of your classpath is not c:\sourcefolder, but some other value (probably the directory you start your jsp engine from) You will have to import all non-java-library classes because the jsp itself becomes a java class, with a package that is determined by the jsp engine.

Import statement -- Filesize^

How does the import statement work anyway?
Will it just "paste" the imported files in front of th class like a C preprocessor?
If so, is there a way to import packages only once?
I use (e. g.) java.awt.point in nearly ALL classes in my project, and at the moment, I import the class in every single file. If it will be pasted, this will significantly enlarge my project, I fear. Or does the compiler recognize double imports?

How does the import statement work anyway?The import statement just gives the compiler some info so you don't have to fully qualify the class names.
Will it just "paste" the imported files in front of th
class like a C preprocessor?No
It doesn't put anything into the compiled class, so won't affect the file size.

Import Statement - Which is Better ???

Which import statement is better? Are there any performance advantages of calling the ones you need explicitly instead of using the shorthand (.*)?
import java.util.*
or
import java.util.Vector;
import java.util.TreeMap;

there is no runtime performance difference. There could be a difference in compliation time if you use wildcards, but even that difference would probably be insignificant (plus, is compile time usually a concern in java?). The main advantage to importing only the classes you need, as the previous poster pointed out, is to reduce compilation ambiguities (e.g. does 'Date' refer to java.sql.Date or java.util.Date). For example, a recent poster just reported a problem where he imported java.beans.* and java.sql.* and, after upgrading to 1.4, none of his code compiles because both packages now have a Statement class, which causes ambiguities. As a general rule, it is best to import only the classes you need.

Import statement and directory structure

First of all, sorry for such a long post, I believe part of it is because I am unsure of the concept of importing in Java. Secondly, Thanks to anyone who can ultimately enlighten me to the concept of import. I did ask this question before in the "erorr and error handling" forum, and the people who have helped me there did a great job. But, I believe I require a little more clarification and thus have decided to post here.
Anyhow, my question..
Could someone explain to me the concept of the import statement, or direct me to a webpage with sort of explanation for newbies? For some reason, I am having a hard time grasping the concept.
As I understand it, the import statement in Java, is very similar to the namespace keyword in C. That is to say, import doesn't actually "import" any source code, the way that the #include statement does in C.
So I suppose what my question is, say I have a java class file like below:
//filename: sentence.java
//located: c:\school\csc365
package csc365;
class sentence
//some variables here..
//some constructor here..
//some methods here..
And some sample program like the one below which implements the above..
//filename: test.java
//located: c:\school\csc365
import csc365.*;
import java.io.*;
class test.java
//creates some sentence object
//uses the object's methods
//some other things.
As I understand it, the test.java file should not compile because the csc365 package is not in the correct directory. (assuming of course, the classpath is like c:\school\csc365;c:\school )
But, ... where then should the sentence.java be located? In a subdirectory of c:\school called csc365 (i.e c:\school\csc365\) ?
And thus that would mean the test.java file could be located anywhere on the hard drive?
I suppose, I just need a little clarification on the correlation between a package's "name" (i.e package csc365; ) and its corresponding directory's name, and also how the javac compiler searches the classpath for java classes.
..So, theoretically if I were to set the classpath to look in every conceivable directory(provided the directory names were all unique) of the harddrive, then I could compile a test.java anywhere?
As a note: I have been able to get the test.java file to compile, by leaving out the import statement in the test.java file, and also leaving out the package statement for the sentence class, but I assume this is because the files are defaulted to the same package?

Hi Mary,
No, import isn't analogous to C++ namespace - Java package is closer to the namespace mark.
import is just a convenience for the programmer. You can go your whole Java career without ever writing an import statement if you wish. All that means is that you'll have to type out the fully-resolved class name every time you want to use a class that's in a package other than java.lang. Example:
// NOTE: No import statements
public class Family
   // NOTE: fully-resolved class names
   private java.util.List children = new java.util.ArrayList();
}If you use the import statement, you can save yourself from typing:
import java.util.ArrayList;
import java.util.List;
public class Family
   // NOTE: fully-resolved class names
   private List children = new ArrayList();
}import isn't the same as class loader. It does not bring in any source code at all.
import comes into play when you're compiling or running your code. Java will check to make sure that any "shorthand" class names you give it live in one of the packages you've imported. If it can't find a matching fully-resolved class name, it'll give you a message like "Symbol not found" or something like that.
I arrange Java source in a directory structure that matches the package structure in the .class files.
If I've got a Java source file like this:
package foo.bar;
public class Baz
   public static void main(String [] args)
        Baz baz = new Baz();
        System.out.println(baz);
   public String toString()
       return "I am a Baz";
}I'll store it in a directory structure like this:
root
+---classes
+---src
      +---foo
           +---bar
                +---Baz.javaWhen I compile, I go to root and compile by typing this:
javac -d classes foo/bar/*.javaI can run the code from root by typing:
java -classpath classes foo.bar.BazI hope this wasn't patronizing or beneath you. I don't mean to be insulting. - MOD

Import statement in .java files and .jsp files

Guys I have few mysteries about this import statement.
Please correct me if I am wrong.
1)Suppose if I have a folder c:\SourceFolder it has one.java and two.java files.If I compile one.java then one.class files is created in c:\ClassFolder .Now two.java uses one of the method of one.java,and without using import statement I am able to compile two.java, and two.class file is created in c:\ClassFolder.I assume that the path of one.class was taken from the CLASSPATH environment variable,hence I there was no need for import statement .........am i right ?
BUT... in My.jsp,which is in C:\JspFolder, if I want to use one.class,then I have to specifically import the class I want to use.That is i have to say
<%@page import="one"%>
and since the classpath is C:\ClassFolder ,it finds one.class in the C:\ClassFolder.(Note that My.class is created in a folder different from c:\ClassFolder )
But I am wondering why was there no need for me to import one.class in two.java.
(Note I am using JDeveloper and Apache server)
Please help.
In this case the pSo I am wondering in JSP why it doesn't take the class I am looking for from the classpath .
Help.

You have to understand Java scoping rules. In the 1st scenario with the two Java files I am guessing neither one of them begins with a package statement. This means that they belong to the default package. When you compile the compiler uses the classpath to resolve method calls looking in the default package since there was no import statement specified in two.java. JSP is a little different. Now I just read this here in these forums a couple of days ago. Since the classfiles generated from the JSP files are not in the CLASSPATH they are loaded by a different classloader. This is why you have to import all references to all classes in the default package.

Import statement in .java files and .jsp files ..correction

Guys I have few mysteries about this import statement.
Please correct me if I am wrong.
1)Suppose if I have a folder c:\SourceFolder it has one.java and two.java files.If I compile one.java then one.class files is created in c:\ClassFolder .Now two.java uses one of the method of one.java,and without using import statement in two.java I am able to compile two.java, and two.class file is created in c:\ClassFolder.I assume that the path of one.class was taken from the CLASSPATH environment variable,hence I there was no need for import statement .........am i right ?
BUT... in My.jsp,which is in C:\JspFolder, if I want to use one.class,then I have to specifically import one.class in My.jsp .That is i have to say
<%@page import="one"%>
in My.jsp.
and since the classpath is C:\ClassFolder ,it finds one.class in the C:\ClassFolder and MyJsp is compiled sucessfully.(Note that My.class is created in a folder different from c:\ClassFolder )
But I am wondering why was there no need for me to import one.class in two.java.
(Note I am using JDeveloper and Apache server)
Please help.

It has to do with packages. Most java classes are in a package, the name of which must conform to its place on the filesystem relative to the classpath. By that I mean that if you have com.mystuff.One.java, it must be in a folder com/mystuff where com is located somewhere in the classpath.
What you've done is a little different. I'm assuming a couple of things:
1. you have no package declaration at the top of one.java or two.java
2. you have the current directory "." in your classpath.
Java has the concept of the "default package", which covers classes without a declared package, and in your case is the current directory.
So when you're in c:\sourcefolder and run the compiler, then "."="c:\sourcefolder", and that directory is part of the default package. No import statements are necessary for classes that are in the same package. This is why two.java can call methods in one.java without an import statement.
When you run your jsp, the "current directory" part of your classpath is not c:\sourcefolder, but some other value (probably the directory you start your jsp engine from) You will have to import all non-java-library classes because the jsp itself becomes a java class, with a package that is determined by the jsp engine.

Javac(1.4.2) gives error in import statement

Hi All,
I am facing a surprising problem. I have 2 java class files. I write the import statement for second one in the first one. There is no package & these are in the same directory. I have compiled the second one. But when I try to compile the First one. Javac throws error at import statement like below :
D:\Clubs\oct\6>javac -d . ManojTest.java
ManojTest.java:1: '.' expected
import SessionBean;
^
1 error
My Java Files are as below :
import SessionBean;
public class ManojTest
public static void main(String args[])
//ManojTest.java
public class SessionBean
public static void main(String args[])
//SessionBean.java
I have compiled SessionBean.java successfully but when I try to compile ManojTest.java I get error mentioned above.
However this probelm comes when I use j2se 1.4.2.. but works in j2se 1.3.1..
Another way could be I use package structure.
But I can't do any of these, as I have to port my big project to j2se1.4.2.. from j2se1.3.1.. (Live project is running on Tomcat).
Problems is similar in Unix & Windows both.
Is this javac compiler issue or there is some setting which I can make.
I have already included . (dot) in PATH & CLASSPATH environment varibales.
Please help me out if there is any way around this, as i am stuck up in between
thank you
Manoj :confused:

Use a package and then add that package in your classpathOr don't use a package, leave the file in the default (noname) package, and don't use the import statement. Java will find it in the default package without the import.
Explicit import statements from the default package are no longer allowed

Unused packages in import statement

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