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copied!<p>Reading the answers I found no real test really getting to the point. Here are my 2 cents :</p> <pre><code>public class ConstTest { private final int value = 10; private static final int valueStatic = 20; private final File valueObject = new File(""); private static final File valueObjectStatic = new File(""); public void printAddresses() { System.out.println("final int address " + ObjectUtils.identityToString(value)); System.out.println("final static int address " + ObjectUtils.identityToString(valueStatic)); System.out.println("final file address " + ObjectUtils.identityToString(valueObject)); System.out.println("final static file address " + ObjectUtils.identityToString(valueObjectStatic)); } public static void main(final String args[]) { final ConstTest firstObj = new ConstTest(); final ConstTest sndObj = new ConstTest(); firstObj.printAdresses(); sndObj.printAdresses(); } } </code></pre> <p>Results for first object :</p> <pre><code>final int address java.lang.Integer@6d9efb05 final static int address java.lang.Integer@60723d7c final file address java.io.File@6c22c95b final static file address java.io.File@5fd1acd3 </code></pre> <p>Results for 2nd object :</p> <pre><code>final int address java.lang.Integer@6d9efb05 final static int address java.lang.Integer@60723d7c final file address java.io.File@3ea981ca final static file address java.io.File@5fd1acd3 </code></pre> <p>Conclusion :</p> <p>As I thought java makes a difference between primitive and other types. Primitive types in Java are always "cached", same for strings literals (not new String objects), so no difference between static and non-static members.</p> <p>However there is a memory duplication for non-static members if they are not instance of a primitive type.</p> <p>Changing value of valueStatic to 10 will even go further as Java will give the same addresses to the two int variables.</p>

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