AdviceVariableAccessTest.java

package net.bytebuddy.asm;

import net.bytebuddy.ByteBuddy;
import net.bytebuddy.dynamic.loading.ClassLoadingStrategy;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.Parameterized;

import java.util.Arrays;
import java.util.Collection;

import static net.bytebuddy.matcher.ElementMatchers.named;
import static org.hamcrest.CoreMatchers.is;
import static org.hamcrest.CoreMatchers.nullValue;
import static org.hamcrest.MatcherAssert.assertThat;

@RunWith(Parameterized.class)
public class AdviceVariableAccessTest {

    private static final String READ = "read", WRITE = "write";

    @Parameterized.Parameters
    public static Collection<Object[]> data() {
        return Arrays.asList(new Object[][]{
                {BooleanSample.class, true, boolean.class},
                {ByteSample.class, (byte) 42, byte.class},
                {ShortSample.class, (short) 42, short.class},
                {CharacterSample.class, (char) 42, char.class},
                {IntegerSample.class, 42, int.class},
                {LongSample.class, 42L, long.class},
                {FloatSample.class, 42f, float.class},
                {DoubleSample.class, 42d, double.class},
                {ReferenceSample.class, "foo", Object.class},
        });
    }

    private final Class<?> sample, type;

    private final Object value;

    public AdviceVariableAccessTest(Class<?> sample, Object value, Class<?> type) {
        this.sample = sample;
        this.value = value;
        this.type = type;
    }

    @Test
    public void testArray() throws Exception {
        Class<?> dynamicType = new ByteBuddy()
                .redefine(sample)
                .visit(Advice.to(AdviceVariableAccessTest.class).on(named(READ).or(named(WRITE))))
                .make()
                .load(ClassLoadingStrategy.BOOTSTRAP_LOADER, ClassLoadingStrategy.Default.WRAPPER)
                .getLoaded();
        Object instance = dynamicType.getDeclaredConstructor().newInstance();
        assertThat(dynamicType.getDeclaredMethod(WRITE, type).invoke(instance, value), nullValue(Object.class));
        assertThat(dynamicType.getDeclaredMethod(READ).invoke(instance), is(value));
    }

    @Advice.OnMethodExit
    private static void advice() {
        /* empty */
    }

    public static class BooleanSample {

        private final boolean[] array = new boolean[1];

        public void write(boolean value) {
            array[0] = value;
        }

        public boolean read() {
            return array[0];
        }
    }

    public static class ByteSample {

        private final byte[] array = new byte[1];

        public void write(byte value) {
            array[0] = value;
        }

        public byte read() {
            return array[0];
        }
    }

    public static class ShortSample {

        private final short[] array = new short[1];

        public void write(short value) {
            array[0] = value;
        }

        public short read() {
            return array[0];
        }
    }

    public static class CharacterSample {

        private final char[] array = new char[1];

        public void write(char value) {
            array[0] = value;
        }

        public char read() {
            return array[0];
        }
    }

    public static class IntegerSample {

        private final int[] array = new int[1];

        public void write(int value) {
            array[0] = value;
        }

        public int read() {
            return array[0];
        }
    }

    public static class LongSample {

        private final long[] array = new long[1];

        public void write(long value) {
            array[0] = value;
        }

        public long read() {
            return array[0];
        }
    }

    public static class FloatSample {

        private final float[] array = new float[1];

        public void write(float value) {
            array[0] = value;
        }

        public float read() {
            return array[0];
        }
    }

    public static class DoubleSample {

        private final double[] array = new double[1];

        public void write(double value) {
            array[0] = value;
        }

        public double read() {
            return array[0];
        }
    }

    public static class ReferenceSample {

        private final Object[] array = new Object[1];

        public void write(Object value) {
            array[0] = value;
        }

        public Object read() {
            return array[0];
        }
    }
}