dcevm/dcevm/src/test/java7/com/github/dcevm/test/structural/ThisTypeChange.java

/*
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 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.structural;

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__;

/**
 * Tests that change the type of the object references by the Java this pointer.
 *
 * @author Thomas Wuerthinger
 */
public class ThisTypeChange {

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

    // Version 0
    public static class A {

        public int valueOK() {
            return 1;
        }

        public int value() {
            __toVersion__(1);
            return 1;
        }
    }

    public static class B extends A {

        @Override
        public int value() {
            return super.value();
        }


        @Override
        public int valueOK() {
            __toVersion__(1);
            return super.valueOK();
        }
    }

    // Version 1
    public static class A___1 {

        public int valueOK() {
            return 2;
        }
    }

    // Version 1
    public static class B___1 {
    }

    // Method to enforce cast (otherwise bytecodes become invalid in version 2)
    public static A convertBtoA(Object b) {
        return (A) b;
    }

    @Test
    public void testThisTypeChange() {

        assert __version__() == 0;

        final B b = new B();
        TestUtil.assertUnsupported(new Runnable() {
            @Override
            public void run() {
                b.value();
            }
        });

        assert __version__() == 0;

        TestUtil.assertUnsupported(new Runnable() {
            @Override
            public void run() {
                b.valueOK();
            }
        });

        assert __version__() == 0;

        TestUtil.assertUnsupported(new Runnable() {
            @Override
            public void run() {
                b.valueOK();
            }
        });

        assert __version__() == 0;
    }
}