Types of Errors

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Types of Errors

Errors may be broadly classified into two:

Compile time errors

Run time errors

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Compile Time Errors

All Syntax errors are detected and displayed by Java Compiler and therefore these errors are known as Compile time errors.

Java will not create .class file until the program compiled successfully.

Therefore it is necessary to fix all the errors before we compile and run the java program.

Sometimes,a single error may be the source of multiple errors,later in the compilation.

Most of the compile time errors are due to typing mistakes.The most common problems are:

Missing semicolon

Missing or mismatch of brackets

Misspelling of identifiers and keywords

Missing double quotes

Use of undeclared variables

Bad reference to objects

Use of = in place of == and so on.

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Run Time Errors

Sometimes a program may be compiled successfully and the .class file will be created but may not run properly.

Such programs may produce wrong output due to logical error or may terminate due to errors such as Overflow.

Most common Run Time errors are;

Dividing an integer by zero

Accessing the element out of the bounds of an Array

trying to store a value into an array of an incompatible class or type.

Trying to illegally change the state of a thread and many more.