java.lang.ArrayIndexOutOfBoundsException

It's a very common runtime error message or exception we face when we use array wrongly. Very specifically this exception is thrown to indicate that an array has been accessed with an illegal index (location / position / subscript). The index is either negative or greater than or equal to the size of the array. See the following code: int data[]={5,7,18,21,27,15,3}; //show the array elementsfor(int...

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array dimension missing

'array dimension missing' is shown when the array size is not specified while allocating memory for the array or creating an array. See below: int data[ ]=new int[ ]; See that, blank [ ] is given in new int[ ]. We must give an int as the size of the array. Memory will be allocated for the array according to the given int within the [ ] as below: int data[]=new int[...

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illegal initializer

You may see this error for writing wrong expression to initialize an array. See the code below: int data={42,15,27,20,19}; If you compile this, you will see the following error message: illegal initializer for intint data={42,15,27,20,19}; ^ Here the array is not declared properly as we have not put [ ] for declaring the array. The correct code is: int data[ ]={42,15,27,20,19}; or int[ ]...

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incompatible types

1. Sometimes we may get the following error message in an 'if' (selection) structure. incompatible typesfound : intrequired: boolean This is because, we have not specified a boolean expression as the condition of the 'if'; instead we might have written such an expression which is may be int, float, String or other types but not boolean. See the code below: int a=10,b=10; if(a=b){ System.out.println("a...

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cyclic inheritance involving ...

public class Person extends Employee{ private String firstName; private String lastName; public Person(String firstName,String lastName) { this.firstName=firstName; this.lastName=lastName; } } Person is a class which inherits Employee and see the code below where Employee also inherit the Class Person. public class Employee extends Person{ private double salary; public Employee(String firstName,String...