Default Value of Local Variables in Java: None

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問題：

In Java What is the default value stored in Local Variables?

答案：

In Java, local variables do not have a default value. Unlike instance variables (fields of a class) and static variables, which are automatically initialized to default values (e.g., 0 for numeric types, false for boolean, null for object references), local variables must be explicitly initialized before they can be used. If you try to use a local variable without initializing it, the Java compiler will throw a compilation error.

Here's an example to illustrate this:

public class Example {
    public void myMethod() {
        int localVar; // local variable declared but not initialized
        // System.out.println(localVar); // This will cause a compilation error
        localVar = 10; // Now it's initialized
        System.out.println(localVar); // This will work fine
    }
}

In the above code, if you uncomment the line that tries to print localVar before it is initialized, you will get a compilation error indicating that the variable might not have been initialized.

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