Common Errors and Mistakes

• Using == instead of equals() for comparing the contents of objects (like strings)
• Trying to access an instance variable in a static method (like main)
• Forgetting a cast when pulling an object out of a collection
• Off by one errors (index of an array or start or end of a loop)
• Null pointer exceptions. Declaring an object reference doesn't create the object!

• Wrong case for keywords (should be all lowercase)
• Wrong case for class names (should start with an uppercase letter)
• Wrong case for fields and methods (should start with an lowercase letter). The first letter of each additional word should be uppercase.

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• Java Resources last edited on 14 September 2010 at 8:22 pm by user-112155i.dsl.mindspring.com