Sometimes the condition in Java class needs to compare between a constant string and a variable.

For example: variable.equals(CONSTANT_STRING);

Now suppose if the variable is not initialized then the above statement throws a null pointer exception.

To avoid this null pointer exception you can re-write the above statement:

CONSTANT_STRING.equals(variable);

 Related Tips

• A custom combobox editor for use with the EditableComboBox class
• A demonstration of Java2D transformations
• A game of Tic-Tac-Toe that can be played between two client applets
• A Label that uses inline HTML to format its text
• A program to print limits of the primitive types
• A sample of inline DTD definition
• A sample of linked DTD definition
• A sample XML file