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copied!<p>The relevant chapter in the Java Language Specification is <a href="http://docs.oracle.com/javase/specs/jls/se7/html/jls-3.html#jls-3.10.5" rel="nofollow">here</a>. It states</p> <blockquote> <p>Moreover, a string literal always refers to the same instance of class String. This is because string literals - or, more generally, strings that are the values of constant expressions (§15.28) - are "interned" so as to share unique instances, using the method String.intern.</p> </blockquote> <p>So, yes, the <code>String</code> literal <code>"print this line here"</code> is interned.</p> <blockquote> <p>I'm wondering how this works with String constants. So, every time i'm invoking this statement in a loop, is "print this line here" being interned-- looked up in the pool to see whether it's there ... ?</p> </blockquote> <p>Not exactly, byte code is a little different. What you will see is the specific reference to a <code>String</code> object in the class' constant pool be pushed on the stack.</p> <p>You can see this in the byte code</p> <pre><code> public static void main(java.lang.String[]) throws java.lang.Exception; Code: 0: getstatic #2 // Field java/lang/System.out:Ljava/io/PrintStream; 3: ldc #3 // String print this line here 5: invokevirtual #4 // Method java/io/PrintStream.println:(Ljava/lang/String;)V 8: return </code></pre> <p>where the <code>ldc</code> <a href="http://en.wikipedia.org/wiki/Java_bytecode_instruction_listings" rel="nofollow">instruction is used to</a></p> <blockquote> <p>push a constant #index from a constant pool (String, int or float) onto the stack</p> </blockquote> <p>That constant is used in the <code>println()</code> method invocation.</p>

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