Java Boolean Default Value | Generated by AI

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Question: What is the default value of a boolean instance variable in a class?

Answer:

In Java, instance variables (fields) of a class that are not explicitly initialized are automatically assigned default values based on their type.

For primitive types:

• boolean defaults to false
• int, byte, short, long default to 0
• float, double default to 0.0
• char defaults to ‘’ (null character)
• Reference types (e.g., objects, strings) default to null

Therefore, the default value of a boolean instance variable is false.

The correct answer is B. false.

Note: This applies to instance variables and static variables. Local variables (declared inside methods) do not have default values and must be explicitly initialized before use.

References:

• Oracle Java Documentation - Default Values
• Oracle Java Tutorials - Primitive Data Types

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