Error reference

Java error: int cannot be converted to boolean

This page is part of Intro to Java with Greenfoot. It assumes you have reached lesson 2.3. Opening it is not counted against you and is not tracked as progress.

The message

incompatible types: int cannot be converted to boolean

What it actually means

Something that needed a true or false question was given a number or an instruction instead. In an if condition this almost always means = was typed where == was meant.

The usual causes

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

1. Using a single = inside an if: `if (score = 10)` instead of `if (score == 10)`.
2. Using a number as a condition, such as `if (lives)` instead of `if (lives > 0)`.
3. Assigning to a boolean from an int.