Abstract class not visibe

I have written and tested an abstract-class inside a project. Now i moved the abstract class from my project to utility.jar Ten I added this utility.jar to my classpath. Using eclipse as my application devtool, i can see that the class is availabe in the jar (so far so good).
But, when i add the import-statement to use the class in my current project, i get an error that the class is not visible.
any leads?

Praveen_Forum wrote:
-Kayaman- wrote:
Your abstract class isn't a public class?
Basics, basics...we can't make abstract class private can we??I was thinking more default, i.e. package private.

Similar Messages

Abstract classes and methods with dollar.decimal not displaying correctly

Hi, I'm working on a homework assignment and need a little help. I have two classes, 1 abstract class, 1 extends class and 1 program file. When I run the program file, it executes properly, but the stored values are not displaying correctly. I'm trying to get them to display in the dollar format, but it's leaving off the last 0. Can someone please offer some assistance. Here's what I did.
File 1
public abstract class Customer//Using the abstract class for the customer info
private String name;//customer name
private String acctNo;//customer account number
private int branchNumber;//The bank branch number
//The constructor accepts as arguments the name, acctNo, and branchNumber
public Customer(String n, String acct, int b)
    name = n;
    acctNo = acct;
    branchNumber = b;
//toString method
public String toString()
String str;
    str = "Name: " + name + "\nAccount Number: " + acctNo + "\nBranch Number: " + branchNumber;
    return str;
//Using the abstract method for the getCurrentBalance class
public abstract double getCurrentBalance();
}file 2
public class AccountTrans extends Customer //
    private final double
    MONTHLY_DEPOSITS = 100,
    COMPANY_MATCH = 10,
    MONTHLY_INTEREST = 1;
    private double monthlyDeposit,
    coMatch,
    monthlyInt;
    //The constructor accepts as arguments the name, acctNo, and branchNumber
    public AccountTrans(String n, String acct, int b)
        super(n, acct, b);
    //The setMonthlyDeposit accepts the value for the monthly deposit amount
    public void setMonthlyDeposit(double deposit)
        monthlyDeposit = deposit;
    //The setCompanyMatch accepts the value for the monthly company match amount
    public void setCompanyMatch(double match)
        coMatch = match;
    //The setMonthlyInterest accepts the value for the monthly interest amount
    public void setMonthlyInterest(double interest)
        monthlyInt = interest;
    //toString method
    public String toString()
        String str;
        str = super.toString() +
        "\nAccount Type: Hybrid Retirement" +
        "\nDeposits: $" + monthlyDeposit +
        "\nCompany Match: $" + coMatch +
        "\nInterest: $" + monthlyInt;
        return str;
    //Using the getter method for the customer.java fields
    public double getCurrentBalance()
        double currentBalance;
        currentBalance = (monthlyDeposit + coMatch + monthlyInt) * (2);
        return currentBalance;
}File 3
    public static void main(String[] args)
//Creates the AccountTrans object
        AccountTrans acctTrans = new AccountTrans("Jane Smith", "A123ZW", 435);
        //Created to store the values for the MonthlyDeposit,
        //CompanyMatch, MonthlyInterest
        acctTrans.setMonthlyDeposit(100);
        acctTrans.setCompanyMatch(10);
        acctTrans.setMonthlyInterest(5);
        DecimalFormat dollar = new DecimalFormat("#,##0.00");
        //This will display the customer's data
        System.out.println(acctTrans);
        //This will display the current balance times 2 since the current
        //month is February.
        System.out.println("Your current balance is $"
                + dollar.format(acctTrans.getCurrentBalance()));
    }

Get a hair cut!
h1. The Ubiquitous Newbie Tips
* DON'T SHOUT!!!
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h5. Ask a good question
* Don't forget to actually ask a question. No, The subject line doesn't count.
* Don't even talk to me until you've:
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    (b) had a squizzy at the [Java Cheat Sheet|http://mindprod.com/jgloss/jcheat.html] and
    (c) looked it up in [Sun's Java Tutorials|http://java.sun.com/docs/books/tutorial/] and
    (d) read the relevant section of the [API Docs|http://java.sun.com/javase/6/docs/api/index-files/index-1.html] and maybe even
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      - FFS spare us the SMS and L33t speak! Pull your pants up, and get a hair cut!
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Event ID 10801 - Abstract class ID not allowed in a discovery data item.

Hi All,
I am getting very frequent event id 10801 on my RMSE -
Discovery data couldn't be inserted to the database. This could have happened because of one of the following reasons:
- Discovery data is stale. The discovery data is generated by an MP recently deleted.
- Database connectivity problems or database running out of space.
- Discovery data received is not valid.
The following details should help to further diagnose:
DiscoveryId: a8cc450e-fdfa-9ff0-e46f-0b8a3f58a57b
HealthServiceId: 4e1815a1-6704-e686-f490-15d7d46773d2
Microsoft.EnterpriseManagement.Common.DiscoveryDataAbstractClassIdNotAllowedException,Abstract class ID not allowed in a discovery data item.
Class ID: e2ea0f3e-a2ac-41d8-9ba2-7c0b524a121e
Rule ID: a8cc450e-fdfa-9ff0-e46f-0b8a3f58a57b
Instance:
<?xml version="1.0" encoding="utf-16"?><ClassInstance TypeId="{e2ea0f3e-a2ac-41d8-9ba2-7c0b524a121e}"><Settings><Setting><Name>5c324096-d928-76db-e9e7-e629dcc261b1</Name><Value>ABCD.domain.domain</Value></Setting><Setting><Name>af13c36e-9197-95f7-393c-84aa6638fec9</Name><Value>11</Value></Setting></Settings></ClassInstance>.
When I check the Discovery ID it gives me the below discovery.
PS C:\> [guid]$g = "a8cc450e-fdfa-9ff0-e46f-0b8a3f58a57b"
PS C:\> Get-SCOMDiscovery | where {$_.Id -eq $g}
HasNonCategoryOverride          : False
Enabled                         : onEssentialMonitoring
Target                          : ManagementPackElementUniqueIdentifier=3c998a33-cbc3-a258-b728-a67982377058
ConfirmDelivery                 : False
Remotable                       : True
Priority                        : Normal
Category                        : Discovery
DataSource                      : DiscoveryDataSource
DiscoveryClassCollection        : {}
DiscoveryRelationshipCollection : {ManagementPackElementUniqueIdentifier=08d64c2a-2ba5-cafa-54ad-bfe91e2a39b3}
XmlTag                          : Discovery
ManagementGroup                 : SCOMPRODUCTION
ManagementGroupId               : 1a77df0b-1a31-721c-be9d-aebe3f85db8c
Identifier                      : 1|Microsoft.Windows.HyperV.2012.Discovery/31bf3856ad364e35|1.0.0.0|Microsoft.Windows.
                                  HyperV.2012.VirtualNetworkContainsNetworkAdapterDiscovery||
Name                            : Microsoft.Windows.HyperV.2012.VirtualNetworkContainsNetworkAdapterDiscovery
Id                              : a8cc450e-fdfa-9ff0-e46f-0b8a3f58a57b
DisplayName                     : Hyper-V 2012 Virtual Network Relationship Discovery
Description                     : Discovers Microsoft Windows Hyper-V 2012 Virtual Network contains Network Adapter
                                  relationship
LanguageCode                    : ENU
Comment                         :
Status                          : Unchanged
LastModified                    : 12/11/2014 12:18:01 AM
TimeAdded                       : 12/11/2014 12:18:01 AM
InstanceName                    :
PS C:\>
I am getting this event for multiple agents now. I checked the discovery highlighted "Hyper-V 2012 Virtual Network Relationship Discovery" but did not get anything.
Can anybody help me in resolving this.
Thanks, S K Agrawal

Microsoft.Windows.HyperV.2012.VirtualNetworkContainsNetworkAdapterDiscoveryDataSourceModule Code (Code executed for your discovery Hyper-V 2012 Virtual Network Relationship Discovery)
Set oNIC = oDiscoveryData.CreateClassInstance("$MPElement[Name='WSLib!Microsoft.Windows.Server.NetworkAdapter']$")
      Call oNIC.AddProperty("$MPElement[Name='Windows!Microsoft.Windows.LogicalDevice']/DeviceID$", nicId)
      Call oNIC.AddProperty("$MPElement[Name='Windows!Microsoft.Windows.Computer']/PrincipalName$", ComputerIdentity)
This class (Microsoft.Windows.Server.NetworkAdapter) is defined as abstract class in “Microsoft.Windows.Server.Library.mp”
<ClassType ID="Microsoft.Windows.Server.NetworkAdapter"
Abstract="true" Accessibility="Public" Base="Windows!Microsoft.Windows.NetworkAdapter" Hosted="true" Singleton="false">
This was filed as a Bug with Microsoft.
Thanks, S K Agrawal

Why interfaces why not abstract classes?

why they are using interfaces concept in JDBC or struts2.0 why not abstract classes?
thanks in advance.

user5287726 wrote:
jverd wrote:
user5287726 wrote:
Interfaces are more flexible. For certain definitions of flexible, yes, but not for others.
A Java class can only inherit one class, but it can implement multiple interfaces.Which has absolutely nothing to do with why JDBC declares interfaces rather than abstract classes.How does your post even attempt to answer the OP's question?OP asked: "why they are using interfaces concept in JDBC or struts2.0 why not abstract classes?" I'm pointing out that your post does not address the question asked. And of course your answer is wrong anyway.
As for addressing the OP's question, I did that in my first response.

BUG:generate accessors not doing anything on abstract class

I can't get a source file (abstract class) to generate accessors. I am using 10.1.3.0.0 production release. Concrete classes generate accessors fine.
Here is how to reproduce the problem:
Create an interface MyInterface with getMyThing() and setMyThing(String thing)
Create an abstract class that implements MyInterface
add a property and select generate accessor either from the source or from the menu "source"
nothing happens
remove the abstract keyword and the interface implementation -- generate accessors work fine
Message was edited by:
jgammon

actually -- jdev version is 10.1.3.0.4 (SU1) build is JDEVADF_10.1.3_NT_060125.0900.3673

Extending Abstract Classes such I ByteBuffer?

Sorry for the cross post but I think I posted this in the wrong forum origanally.
I need to extend ByteBuffer so I did so like this:
public abstract class SerialPortBuffer extends ByteBuffer {
but now I am getting:
Implicit super constructor ByteBuffer() is undefined for default constructor. Must define an explicit constructor
How do I fix this? Sorry for the newbie questions and the goof on the cross post.

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
But I dodnot think defining a no args constructor explicitly would remove the problem, since the no args constructor is still undefined in the super class. You need to define a constructor woth some arguments
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
public abstract class SerialPortBuffer extends ByteBuffer {
     * @param arg0
     * @param arg1
     * @param arg2
     * @param arg3
     SerialPortBuffer(int arg0, int arg1, int arg2, int arg3) {
          super(arg0, arg1, arg2, arg3);
          // TODO Auto-generated constructor stub
When I try this I get.
The constructor ByteBuffer(int, int, int, int) is not visibe
Can anyone tell me how to extend ByteBuffer?

Calling a super.ssuper.method but your super is a abstract class.

Dear guys,
Is that possible to invoke your super's super's method but your super is a abstract class?
like:
class GO { public void draw() { } }
abstract class GORunner extends GO {}
class GOCounter extends GORunner {
public void draw() {
super.super.draw();
I want to do this because I would like to take advantages of the abstract as an layer to achieve some polymorphism programming Therefore, in the later stage of the programming some code may only refer to GORunner but actually it is holding a GOCounter object.
Thank!!

BTW you don't need to write this
public void draw() {
super.draw();
}It works but its basically the same as not having it at all.

Calling a method from an abstract class in a seperate class

I am trying to call the getID() method from the Chat class in the getIDs() method in the Outputter class. I would usually instantiate with a normal class but I know you cant instantiate the method when using abstract classes. I've been going over and over my theory and have just become more confused??
Package Chatroom
public abstract class Chat
   private String id;
   public String getID()
      return id;
   protected void setId(String s)
      id = s;
   public abstract void sendMessageToUser(String msg);
Package Chatroom
public class Outputter
public String[] getIDs()
     // This is where I get confused. I know you can't instantiate the object like:
        Chat users=new Chat();
        users.getID();
I have the two classes in the package and you need to that to be able to use a class' methods in another class.
Please help me :(

I have just looked over my program and realised my class names are not the most discriptive, so I have renamed them to give you a clearer picture.
package Chatroom
public abstract class Chatter
private String id;
public String getID()
return id;
protected void setId(String s)
id = s;
I am trying to slowly build a chatroom on my own. The Chatter class is a class that will be used to represent a single logged in user and the user is given an ID when he logs in through the setId and getID() methods.
package Chatroom;
import java.util.Vector;
public class Broadcaster
private Vector<Chatter> chatters = new Vector<Chatter>();
public String[] getIDs()
// code here
The Broadcaster class will keep a list of all logged-in users keeps a list of all the chats representing logged-in users, which it stores in a Vector.I am trying to use the getIDs() method to return an array of Strings comprising the IDs of all logged-in users, which is why im trying to use the getID() method from the Chat class.
I apologise if I come across as clueless, it's just I have been going through books for about 4 hours now and I have just totally lossed all my bearings

EJB question: How to use abstract class in writing a session bean?

I had written an abstract class which implements the session bean as follow:
public abstract class LoggingSessionBean implements SessionBean {
protected SessionContext ctx;
protected abstract Object editRecord(Object obj) throws Exception;
public LoggingSessionBean()
super();
private final String getBeforeUpdateImage(Object obj) throws Exception {
// implement the details of extracting the backup image ...
public void setSessionContext(SessionContext ctx)
this.ctx = ctx;
private final void writeThisImageToDatabase(String aStr) {
// connect to database to write the record ...
public final Object update(final Object obj) {
try {
final String aStr = getBeforeUpdateImage(obj);
writeThisImageToDatabase(aStr);
editRecord(obj);
} catch (Exception e) {
ctx.setRollbackOnly();
This abstract class is to write the backup image to the database so that other session beans extending it only need to implement the details in editRecord(Object Obj) and they do not need to take care of the operation of making the backup image.
However, some several questions for me are:
1. If I write a class ScheduleSessionBean extending the above abstract class and the according 2 interfaces ScheduleSession and ScheduleSessionHome for this session bean (void update(Object obj); defined in ScheduleSession), do I still need to write the interfaces for LoggingSession and LoggingSessionHome?
2. If I wrote the interface LoggingSession extending EJBObject where it defined the abstract methods "void update(Object obj);" and "void setSessionContext(SessionContext ctx);", that this meant I needed to write the ScheduleSession to implement the Logging Session?
3. I used OC4J 9.0.4. How can I define the ejb-jar.xml in this case?

Hi Maggie,
1. do I still need to write
the interfaces for LoggingSession and
LoggingSessionHome?"LoggingSessionBean" can't be a session bean, because it's an abstract class. Therefore there's no point in thinking about the 'home' and 'remote' interfaces.
2. this
meant I needed to write the ScheduleSession to
implement the Logging Session?Again, not really a question worth considering, since "LoggingSessionBean" can't be an EJB.
3. I used OC4J 9.0.4. How can I define the
ejb-jar.xml in this case?Same as you define it for any version of OC4J and for any EJB container, for that matter, since the "ejb-jar.xml" file is defined by the EJB specification.
Let me suggest that you create a "Logging" class as a regular java class, and give your "ScheduleSessionBean" a member that is an instance of the "Logging" class.
Alternatively, the "ScheduleSessionBean" can extend the "Logging" class and implement the "SessionBean" interface.
Good Luck,
Avi.

".. is an abstract class. It can't be instantiated"

Does anyone have an idea of how I can get rid of the above error message? Here is a bit of my code:
import java.io.*;
import java.util.Vector;
class Project3 {
private BiTree company = new BiTree();
public static void main(String[] args) throws IOException {
Project3 run = new Project3();
run.Command();
public void Command() throws IOException {}
public interface comparable {
//not sure if need this in this class, or at all
public int compare(Object object1,Object object2);
public void add() {
Employee newOne = new Employee();
System.out.println("Enter name");
BufferedReader stdin = new BufferedReader (new InputStreamReader (System.in));;
String name = stdin.readLine();
System.out.println("Enter title");
BufferedReader stdin = new BufferedReader (new InputStreamReader (System.in));;
String title = stdin.readLine();
System.out.println("Enter payrate");
BufferedReader stdin = new BufferedReader (new InputStreamReader (System.in));;
payrate = Double.parseDouble.stdin.readLine();
newOne.setTitle(title);
newOne.setName(name);
newOne.setPayrate(payrate);
company.insert(newOne);
}

It is not possible to create instances of an abstract class.
I hope this example helps,
abstract class Vehicle
public static void main(String arg[])
Vehicle a;
a = new Automobile(); // ok, since Automobile is a kind of Vehicle
// The class Automobile, a special case of Vehicle
class Automobile extends Vehicle

Abstract Class can't be instantiated

Hi I'm getting the following error messages while compiling. Does any one have any idea how to get RID of it?
ERROR MESSAGES:
EditableHeaderTableExample2.java:48: inner class EditableHeaderTableExample2. MyComboRenderer is an abstract class. It can't be instantiated.
MyComboRenderer renderer = new MyComboRenderer(items);
^
EditableHeaderTableExample2.java:79: Method redefined with different return type: javax.swing.table.TableCellRenderer getTableCellRendererComponent(javax.swing.JTable, java.lang.Object, boolean, boolean, int, int) was java.awt.Component getTableCellRendererComponent(javax.swing.JTable, java.lang.Object, boolean, boolean, int, int)
public TableCellRenderer getTableCellRendererComponent(
^
2 errors
Here is the code:
EditableHeaderTableExample2.java
import java.awt.*;
import java.awt.event.*;
import javax.swing.event.*;
import javax.swing.JComponent;
import javax.swing.JComboBox;
import java.util.*;
import javax.swing.*;
import javax.swing.table.*;
import javax.swing.border.*;
import javax.swing.JTable;
import javax.swing.plaf.metal.*;
import javax.swing.JFrame;
import javax.swing.table.TableColumn;
import javax.swing.table.TableColumnModel;
import javax.swing.DefaultCellEditor;
import javax.swing.table.TableCellRenderer;
import javax.swing.table.DefaultTableCellRenderer;
public class EditableHeaderTableExample2 extends JFrame {
public static void main(String[] args) {
EditableHeaderTableExample2 frame = new EditableHeaderTableExample2();
frame.setSize(400,300);
     frame.setLocation(100,100);
     frame.setVisible(true);
public EditableHeaderTableExample2(){
JTable table = new JTable(10,10);
TableColumnModel columnModel = table.getColumnModel();
table.setTableHeader(new EditableHeader(columnModel));
String[] items = {"Dog","Cat"};
JComboBox combo = new JComboBox();
for (int i=0;i<items.length;i++) {
combo.addItem(items);
MyComboRenderer renderer = new MyComboRenderer(items);
EditableHeaderTableColumn col;
// column 1
col = (EditableHeaderTableColumn)table.getColumnModel().getColumn(1);
col.setHeaderValue(combo.getItemAt(0));
col.setHeaderRenderer(renderer);
col.setHeaderEditor(new DefaultCellEditor(combo));
// column 3
col = (EditableHeaderTableColumn)table.getColumnModel().getColumn(3);
col.setHeaderValue(combo.getItemAt(0));
//col.setHeaderRenderer(renderer);
col.setHeaderEditor(new DefaultCellEditor(combo));
JScrollPane pane = new JScrollPane(table);
getContentPane().add(pane);
class MyComboRenderer extends JComboBox implements TableCellRenderer
MyComboRenderer(String[] items) {
for (int i=0;i<items.length;i++) {
addItem(items[i]);
public TableCellRenderer getTableCellRendererComponent(
JTable table, Object value,
boolean isSelected, boolean hasFocus,
int row, int column) {
setSelectedItem(value);
return this;

This is not a suggestion, it's a requirement. When you say
class MyComboRenderer extends JComboBox implements TableCellRendererthe "implements TableCellRenderer" part is a promise that your class will include a method whose signature is
    Component getTableCellRendererComponent(JTable table, Object value,
                             boolean isSelected, boolean hasFocus,
                             int row, int column);

Difference between abstract class and the normal class

Hi...........
can anyone tell me use of abstract class instead of normal class
The main doubt for me is...
1.why we are defining the abstract method in a abstract class and then implementing that in to the normal class.instead of that we can straight way create and implement the method in normal class right...../

Class vs. interface
Some say you should define all classes in terms of interfaces, but I think recommendation seems a bit extreme. I use interfaces when I see that something in my design will change frequently.
For example, the Strategy pattern lets you swap new algorithms and processes into your program without altering the objects that use them. A media player might know how to play CDs, MP3s, and wav files. Of course, you don't want to hardcode those playback algorithms into the player; that will make it difficult to add a new format like AVI. Furthermore, your code will be littered with useless case statements. And to add insult to injury, you will need to update those case statements each time you add a new algorithm. All in all, this is not a very object-oriented way to program.
With the Strategy pattern, you can simply encapsulate the algorithm behind an object. If you do that, you can provide new media plug-ins at any time. Let's call the plug-in class MediaStrategy. That object would have one method: playStream(Stream s). So to add a new algorithm, we simply extend our algorithm class. Now, when the program encounters the new media type, it simply delegates the playing of the stream to our media strategy. Of course, you'll need some plumbing to properly instantiate the algorithm strategies you will need.
This is an excellent place to use an interface. We've used the Strategy pattern, which clearly indicates a place in the design that will change. Thus, you should define the strategy as an interface. You should generally favor interfaces over inheritance when you want an object to have a certain type; in this case, MediaStrategy. Relying on inheritance for type identity is dangerous; it locks you into a particular inheritance hierarchy. Java doesn't allow multiple inheritance, so you can't extend something that gives you a useful implementation or more type identity.
Interface vs. abstract class
Choosing interfaces and abstract classes is not an either/or proposition. If you need to change your design, make it an interface. However, you may have abstract classes that provide some default behavior. Abstract classes are excellent candidates inside of application frameworks.
Abstract classes let you define some behaviors; they force your subclasses to provide others. For example, if you have an application framework, an abstract class may provide default services such as event and message handling. Those services allow your application to plug in to your application framework. However, there is some application-specific functionality that only your application can perform. Such functionality might include startup and shutdown tasks, which are often application-dependent. So instead of trying to define that behavior itself, the abstract base class can declare abstract shutdown and startup methods. The base class knows that it needs those methods, but an abstract class lets your class admit that it doesn't know how to perform those actions; it only knows that it must initiate the actions. When it is time to start up, the abstract class can call the startup method. When the base class calls this method, Java calls the method defined by the child class.

Abstract method called in an abstract class

Hello,
I am writing some code that I'd like to be as generic as possible.
I created an abstract class called Chromozome. This abstract class has a protected abstract method called initialize().
I also created an abstract class called Algorithm which contains a protected ArrayList<Chromozome>.
I would like to create a non abstract method (called initializePopulation()) which would create instances of Chromozome, call their method initialize() and full the ArrayList with them.
In a practical matter, only subclass of Algorithm will be used, using an ArrayList of a subclass of Chromozome implementing their own version of initialize.
I have been thinking of that and concluded it was impossible to do. But I'd like to ask more talented peaple before forgetting it !
Thanks,
Vincent

Ok, let's it is not impossible, juste that I had no idea of how doing it :-)
The difficulty is that Algorithm will never have to deal with Chromozome itself, but always with subclass of Chromozome. This is usually not an issue, but in that case, Algorithm is required to create instances of the desired subclass of Chromozome, but without knowing in advance wich subclass will be used (I hope what I say makes any sense).
Actually I may have found a way in the meantime, but maybe not the best one.
I created in Algorithm an abstract method :
protected abstract Chromozome createChromozome()The method initializePopulation will call createChromozome instead of calling directly the constructor and the initialize() method of Chromozome.
Then subclass of Algorithm will implement the method createChromozome using the desired subclass of Chromozome.

Casting & abstract class & final method

what is casting abstract class & final method in ABAP Objects give some scenario where actually use these.

Hi Sri,
I'm not sure we can be any more clear.
An Abstract class can not be instantiated. It can only be used as the superclass for it's subclasses. In other words it <b>can only be inherited</b>.
A Final class cannot be the superclass for a subclass. In other words <b>it cannot be inherited.</b>
I recommend the book <a href="http://www.sappress.com/product.cfm?account=&product=H1934">ABAP Objects: ABAP Programming in SAP NetWeaver</a>
Cheers
Graham

Can i call non -abstract method in abstract class into a derived class?

Hi all,
Is it possible in java to call a non-abstract method in a abstact class from a class derived from it or this is not possible in java.
The following example will explain this Ques. in detail.
abstract class A
void amethod()
System.out.println(" I am in Base Class");
public class B extends A
void amethod()
System.out.println(" I am in Derived Class");
public static void main (String args[])
// How i code this part to call a method amathod() which will print "I am in Base Class
}

Ok, if you want to call a non-static method from a
static method, then you have to provide an object. In
this case it does not matter whether the method is in
an abstract base class or whatever. You simply cannot
(in any object oriented language, including C++ and
JAVA) call a nonstatic method without providing an
object, on which you will call the method.
To my solution with reflection: It also only works,
if you have an object. And: if you use
getDeclaredMethod, then invoke should not call B's
method, but A's. if you would use getMethod, then the
Method object returned would reflect to B's method.
The process of resolving overloaded methods is
performed during the getMethod call, not during the
invoke (at least AFAIK, please tell me, if I'm wrong).You are wrong....
class A {
    public void dummy() {
         System.out.println("Dymmy in A");
class B extends A {
     public void dummy() {
          System.out.println("Dymmy in B");
     public static void main(String[] args) throws Exception {
          A tmp = new B();
          Class clazz = A.class;
          Method method = clazz.getDeclaredMethod("dummy", null);
          method.invoke(tmp, null);
}Prints:
Dymmy in B
/Kaj

Abstract class not visibe

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