dcevm/dcevm/src/test/java7/com/github/dcevm/test/eval/AddingInterfaceTest.java

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * This code is distributed in the hope that it will be useful, but WITHOUT
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 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
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 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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package com.github.dcevm.test.eval;

import com.github.dcevm.test.TestUtil;
import org.junit.Before;
import org.junit.Test;

import static com.github.dcevm.test.util.HotSwapTestHelper.__toVersion__;
import static com.github.dcevm.test.util.HotSwapTestHelper.__version__;

/**
 * Adds an implemented interface to a class and tests whether an instance of this class can then really be treated as an instance of the interface.
 * Additionally, performs performance measurements of a call to this interface compared to a proxy object.
 *
 * @author Thomas Wuerthinger
 */
public class AddingInterfaceTest {

    @Before
    public void setUp() throws Exception {
        __toVersion__(0);
        assert __version__() == 0;
    }

    public static class A {

        public int getValue() {
            return 1;
        }
    }

    public static interface I {

        public int getValue();
    }

    public static class A___1 implements I {

        @Override
        public int getValue() {
            return 1;
        }
    }

    public static class Proxy implements I {

        private A a;

        public Proxy(A a) {
            this.a = a;
        }

        @Override
        public int getValue() {
            return a.getValue();
        }
    }

    @Test
    public void testAddInterface() {

        A a = new A();
        Proxy p = new Proxy(a);

        final int N = 100000;
        final int Z = 1;


        __toVersion__(1);
        I i = (I) a;

        long startTime = System.currentTimeMillis();
        for (int j = 0; j < Z; j++) {
            calculateSum(N, i);
        }
        long time = System.currentTimeMillis() - startTime;
        System.out.println(time);

        // Must set to null, otherwise local variable i would violate type safety
        i = null;

        TestUtil.assertUnsupportedToVersionWithLight(AddingInterfaceTest.class, 0);

        startTime = System.currentTimeMillis();
        for (int j = 0; j < Z; j++) {
            calculateSum(N, p);
        }
        time = System.currentTimeMillis() - startTime;
        System.out.println(time);
    }

    public int calculateSum(int n, I i) {
        int sum = 0;
        for (int j = 0; j < n; j++) {
            sum += i.getValue();
        }
        return sum;
    }
}