dcevm/dcevm/src/test/java7/com/github/dcevm/test/fields/RedefinePrivateFieldTest.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.fields;

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__;
import static org.junit.Assert.assertEquals;

/**
 * Tests redefinition of a class such that old code still accesses a redefined private field.
 *
 * @author Thomas Wuerthinger
 */
public class RedefinePrivateFieldTest {

    // Version 0
    public static class A {

        private int f1;

        public A() {
            f1 = 5;
        }

        public int foo() {
            int result = f1;
            __toVersion__(1);
            result += f1;
            return result;
        }
    }

    // Version 1
    public static class A___1 {

        int f0;
        int f1;

        public int foo() {
            return -1;
        }
    }

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

    @Test
    public void testRedefinePrivateField() {

        assert __version__() == 0;

        A a = new A();

        assertEquals(10, a.foo());

        assert __version__() == 1;

        assertEquals(-1, a.foo());

        __toVersion__(0);

        assertEquals(10, a.foo());

        assert __version__() == 1;

        assertEquals(-1, a.foo());

        __toVersion__(0);
    }
}