Getting default value for primitive types

The Guava Libraries already contains that:
http://guava-libraries.googlecode.com/svn/trunk/javadoc/com/google/common/base/Defaults.html

Calling defaultValue will return the default value for any primitive type (as specified by the JLS), and null for any other type.

Use it like so:

import com.google.common.base.Defaults;
Defaults.defaultValue(Integer.TYPE); //will return 0

It's possible to get the default value of any type by creating an array of one element and retrieving its first value.

private static <T> T getDefaultValue(Class<T> clazz) {
    return (T) Array.get(Array.newInstance(clazz, 1), 0);
}

This way there is not need to take account for every possible primitive type, at the usually negligible cost of creating a one-element array.

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