Illegal modifier for parameter ... only final is permitted

A local variable, i.e., method level variable or a parameter cannot be declared as static or public/private/protected. So local variables must be declared without these modifiers. For example, the following code is wrong:     void methodA(static int param) {         System.out.println(param);     }     void methodB(private int param) {  ...

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This method requires a body instead of a semicolon

The reason for the error "This method requires a body instead of a semicolon" is same as described in the post missing method body, or declare abstrac...

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interface methods cannot have body

Java error "interface methods cannot have body" occurs when body of the method within an interface is defined. See the code below: public interface MyInterface { public void myMetod() { } } Here the method myMethod has body starting at the symbol { and ending at }. An interface can have abstract methods (method without any body). The class that implements the interface defines the body of the...

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invalid method declaration; return type required

The Java error "invalid method declaration; return type required" can occur for any of the following reasons: 1. You are trying to define a constructor (of course without any return type; not even void)  but the constructor name is not given same as the class name. See the wrong code below: public class Employee {  private int id;  private String name;  public employee(int id,String...

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non-static method ... cannot be referenced from a static context

If you try to access a non static member of a class from a static context, you will see ‘non-static method … cannot be referenced from a static context’. For example, you might have tried to call a non static method from a static method. Bear in mind, you can access a static member (variables, methods etc) from both static and non-static context but cannot access non-static member from a static context. See...

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identifier expected

This error message is shown when the statements are not written in proper place. Most often, mistakenly, we may write the processing task (for example assigning value to a variable; writing a loop etc.) outside of any method. In this situation we may see this type of error message. Then the solution is to write such statements inside the appropriate methods. See the example code below: public class...

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Exception in thread "main" java.lang.NoSuchMethodError: main

'Exception in thread "main" java.lang.NoSuchMethodError: main' is a run time error message. If the main method is not properly defined, we may see this error message. You know if you want to execute/run a program that program must have a main method of the following signature: public static void main(String args[]) Generally we do the following mistakes in this regard: 1. May be, you haven't defined...

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is already defined

If we declare a variable in a method more than once than we see ' is already defined'. Find out the variable for which the message is shown and check whether you have declared the variable more than one time in a particular block. If we compile the following code we will see 'country is already defined in myMethod()' public class AlreadyDefinedSolution { public void myMethod() { String country; String...

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missing method body, or declare abstract

If we put a ; (semicolon) after the method header (i.e., before starting the method body) when we are defining a concrete method (which method has body) then we will see “missing method body, or declare abstract”. Another reason is if we don’t write the keyword ‘abstract’ for an abstract method (a method without body), we’ll also see this message. To resolve the problem we must remove the ; (semicolon)...

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cannot find symbol / cannot resolve symbol

“cannot find symbol” or “cannot resolve symbol” is the most common error message which the programmers get from the compiler. However this error message may mean that the variable/method/class/object used are not declared/defined properly. In most cases, this happens because: · The variable/object is not declared or the spelling of variable/object declaration & later use of that variable/object...

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