Error reference

Java error: variable is already defined

This page is part of Intro to Java with Greenfoot. It assumes you have reached lesson 2.1. Opening it is not counted against you and is not tracked as progress.

The message

variable X is already defined in method Y

What it actually means

You declared the same variable name twice in the same place. The second declaration is trying to make a box that already exists.

The usual causes

Ranked by how often each one turns out to be the answer. Work down the list.

1. Writing the type again on a later line: `int score = 0;` then `int score = 10;`.
2. Two variables with the same name in the same method.
3. A parameter and a local variable sharing a name.