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copied!<p>Any variable or method that is declared <strong>static</strong> can be used independently of a class instance.</p> <p><strong>Experiment</strong></p> <p>Try compiling this class:</p> <pre><code>public class HelloWorld { public static int INT_VALUE = 42; public static void main( String args[] ) { System.out.println( "Hello, " + INT_VALUE ); } } </code></pre> <p>This succeeds because the variable <code>INT_VALUE</code> is declared static (like the method <code>main</code>).</p> <p>Try compiling this class along with the previous class:</p> <pre><code>public class HelloWorld2 { public static void main( String args[] ) { System.out.println( "Hello, " + HelloWorld.INT_VALUE ); } } </code></pre> <p>This succeeds because the <code>INT_VALUE</code> variable is both <strong>static</strong> and <strong>public</strong>. Without going into too much detail, it is usually good to avoid making variables public.</p> <p>Try compiling this class:</p> <pre><code>public class HelloWorld { public int int_value = 42; public static void main( String args[] ) { System.out.println( "Hello, " + int_value ); } } </code></pre> <p>This does not compile because there is no object instance from the class HelloWorld. For this program to compile (and run), it would have to be changed:</p> <pre><code>public class HelloWorld { public int int_value = 42; public HelloWorld() { } public static void main( String args[] ) { HelloWorld hw = new HelloWorld(); System.out.println( "Hello, " + hw.int_value ); } } </code></pre>

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