A DESCRIPTION OF THE REQUEST :
when a declaration of a variable is made there are times when the compiler or runtime knows a more specific types of the variable then the declaration


JUSTIFICATION :

If the code uses the more specific declaration then hotspot can optimes the code in some cases

as can be seen from the results below

testLL1: 190 ms testLL2: 30 ms testLL3: 200 ms testAL1: 191 ms testAL2: 30 ms testAL3: 190 ms
testLL1: 200 ms testLL2: 30 ms testLL3: 211 ms testAL1: 190 ms testAL2: 40 ms testAL3: 190 ms
testLL1: 191 ms testLL2: 30 ms testLL3: 190 ms testAL1: 200 ms testAL2: 30 ms testAL3: 191 ms
testLL1: 220 ms testLL2: 40 ms testLL3: 190 ms testAL1: 190 ms testAL2: 30 ms testAL3: 191 ms
testLL1: 190 ms testLL2: 30 ms testLL3: 230 ms testAL1: 201 ms testAL2: 30 ms testAL3: 210 ms
testLL1: 200 ms testLL2: 30 ms testLL3: 201 ms testAL1: 190 ms testAL2: 40 ms testAL3: 190 ms
testLL1: 251 ms testLL2: 60 ms testLL3: 260 ms testAL1: 190 ms testAL2: 30 ms testAL3: 211 ms
testLL1: 210 ms testLL2: 40 ms testLL3: 250 ms testAL1: 191 ms testAL2: 30 ms testAL3: 200 ms
testLL1: 230 ms testLL2: 40 ms testLL3: 191 ms testAL1: 180 ms testAL2: 40 ms testAL3: 180 ms
testLL1: 191 ms testLL2: 30 ms testLL3: 190 ms testAL1: 190 ms testAL2: 30 ms testAL3: 190 ms

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
in the example javac or hotspot could 'rewrite' the line
final List x = new LinkedList()
to
final LinkedList x = new LinkedList();

to enable the direct jumps to the methods as opposed to the virtual method calls

---------- BEGIN SOURCE ----------

import java.util.ArrayList;
import java.util.LinkedList;
import java.util.List;
import java.util.logging.Logger;

/**
 *
 * @author <a href="mailto:###@###.###">Mike Skells</a> - <a href="http://www.validsoft.com">ValidSoft</a>
 */
public class test10 {
    
    private final static Class loggingClass = test10.class;
    private final static boolean debug = loggingClass.desiredAssertionStatus();
    private final static Logger logger = Logger.getLogger(loggingClass.getName());
    public static void main(String ... args) {
        new test10().run();
    }
    private final static int count = 10000000;
    
    void run() {
        for (int i = 0; i < 10; i++) {
            testLL1();
            testLL2();
            testLL3();
            testAL1();
            testAL2();
            testAL3();
        }
        long time = System.currentTimeMillis();
        for (int i = 0; i < 10; i++) {
            testLL1();
            time = timer(time,"testLL1");
            testLL2();
            time = timer(time,"testLL2");
            testLL3();
            time = timer(time,"testLL3");
            testAL1();
            time = timer(time,"testAL1");
            testAL2();
            time = timer(time,"testAL2");
            testAL3();
            time = timer(time,"testAL3");
            System.out.println();
        }
    }
    
    long timer(long start, String msg) {
        long end = System.currentTimeMillis();
        System.out.print(msg+": "+(end-start)+" ms ");
        return end;
    }
    
    void testLL1() {
        List x = new LinkedList();
        for (int i = 0; i < count; i++) {
            int ignore = x.size();
        }
    }
    void testLL2() {
        LinkedList x = new LinkedList();
        for (int i = 0; i < count; i++) {
            int ignore = x.size();
        }
    }
    void testLL3() {
        final List x = new LinkedList();
        for (int i = 0; i < count; i++) {
            int ignore = x.size();
        }
    }
    void testAL1() {
        List x = new ArrayList();
        for (int i = 0; i < count; i++) {
            int ignore = x.size();
        }
    }
    void testAL2() {
        ArrayList x = new ArrayList();
        for (int i = 0; i < count; i++) {
            int ignore = x.size();
        }
    }
    void testAL3() {
        final List x = new ArrayList();
        for (int i = 0; i < count; i++) {
            int ignore = x.size();
        }
    }
  }

---------- END SOURCE ----------