diff --git a/core-java/src/main/java/com/baeldung/synthetic/BridgeMethodDemo.java b/core-java/src/main/java/com/baeldung/synthetic/BridgeMethodDemo.java new file mode 100644 index 0000000000..bdf6684f78 --- /dev/null +++ b/core-java/src/main/java/com/baeldung/synthetic/BridgeMethodDemo.java @@ -0,0 +1,23 @@ +package com.baeldung.synthetic; + +import java.util.Comparator; + +/** + * Class which contains a synthetic bridge method. + * + * @author Donato Rimenti + * + */ +public class BridgeMethodDemo implements Comparator { + + /* + * (non-Javadoc) + * + * @see java.util.Comparator#compare(java.lang.Object, java.lang.Object) + */ + @Override + public int compare(Integer o1, Integer o2) { + return 0; + } + +} diff --git a/core-java/src/main/java/com/baeldung/synthetic/SyntheticConstructorDemo.java b/core-java/src/main/java/com/baeldung/synthetic/SyntheticConstructorDemo.java new file mode 100644 index 0000000000..d3d75ac05e --- /dev/null +++ b/core-java/src/main/java/com/baeldung/synthetic/SyntheticConstructorDemo.java @@ -0,0 +1,34 @@ +package com.baeldung.synthetic; + +/** + * Wrapper for a class which contains a synthetic constructor. + * + * @author Donato Rimenti + * + */ +public class SyntheticConstructorDemo { + + /** + * We need to instantiate the {@link NestedClass} using a private + * constructor from the enclosing instance in order to generate a synthetic + * constructor. + */ + private NestedClass nestedClass = new NestedClass(); + + /** + * Class which contains a synthetic constructor. + * + * @author Donato Rimenti + * + */ + class NestedClass { + + /** + * In order to generate a synthetic constructor, this class must have a + * private constructor. + */ + private NestedClass() { + } + } + +} \ No newline at end of file diff --git a/core-java/src/main/java/com/baeldung/synthetic/SyntheticFieldDemo.java b/core-java/src/main/java/com/baeldung/synthetic/SyntheticFieldDemo.java new file mode 100644 index 0000000000..1813e03953 --- /dev/null +++ b/core-java/src/main/java/com/baeldung/synthetic/SyntheticFieldDemo.java @@ -0,0 +1,22 @@ +package com.baeldung.synthetic; + +/** + * Wrapper for a class which contains a synthetic field reference to the outer + * class. + * + * @author Donato Rimenti + * + */ +public class SyntheticFieldDemo { + + /** + * Class which contains a synthetic field reference to the outer class. + * + * @author Donato Rimenti + * + */ + class NestedClass { + + } + +} \ No newline at end of file diff --git a/core-java/src/main/java/com/baeldung/synthetic/SyntheticMethodDemo.java b/core-java/src/main/java/com/baeldung/synthetic/SyntheticMethodDemo.java new file mode 100644 index 0000000000..59be4e1429 --- /dev/null +++ b/core-java/src/main/java/com/baeldung/synthetic/SyntheticMethodDemo.java @@ -0,0 +1,48 @@ +package com.baeldung.synthetic; + +/** + * Wrapper for a class which contains two synthetic methods accessors to a + * private field. + * + * @author Donato Rimenti + * + */ +public class SyntheticMethodDemo { + + /** + * Class which contains two synthetic methods accessors to a private field. + * + * @author Donato Rimenti + * + */ + class NestedClass { + + /** + * Field for which will be generated synthetic methods accessors. It's + * important that this field is private for this purpose. + */ + private String nestedField; + } + + /** + * Gets the private nested field. We need to read the nested field in order + * to generate the synthetic getter. + * + * @return the {@link NestedClass#nestedField} + */ + public String getNestedField() { + return new NestedClass().nestedField; + } + + /** + * Sets the private nested field. We need to write the nested field in order + * to generate the synthetic setter. + * + * @param nestedField + * the {@link NestedClass#nestedField} + */ + public void setNestedField(String nestedField) { + new NestedClass().nestedField = nestedField; + } + +} \ No newline at end of file diff --git a/core-java/src/test/java/com/baeldung/synthetic/SyntheticUnitTest.java b/core-java/src/test/java/com/baeldung/synthetic/SyntheticUnitTest.java new file mode 100644 index 0000000000..20f7647f48 --- /dev/null +++ b/core-java/src/test/java/com/baeldung/synthetic/SyntheticUnitTest.java @@ -0,0 +1,99 @@ +package com.baeldung.synthetic; + +import java.lang.reflect.Constructor; +import java.lang.reflect.Field; +import java.lang.reflect.Method; + +import org.junit.Assert; +import org.junit.Test; + +/** + * Unit test for {@link SyntheticFieldDemo}, {@link SyntheticMethodDemo}, + * {@link SyntheticConstructorDemo} and {@link BridgeMethodDemo} classes. + * + * @author Donato Rimenti + * + */ +public class SyntheticUnitTest { + + /** + * Tests that the {@link SyntheticMethodDemo.NestedClass} contains two synthetic + * methods. + */ + @Test + public void givenSyntheticMethod_whenIsSinthetic_thenTrue() { + // Checks that the nested class contains exactly two synthetic methods. + Method[] methods = SyntheticMethodDemo.NestedClass.class.getDeclaredMethods(); + Assert.assertEquals("This class should contain only two methods", 2, methods.length); + + for (Method m : methods) { + System.out.println("Method: " + m.getName() + ", isSynthetic: " + m.isSynthetic()); + Assert.assertTrue("All the methods of this class should be synthetic", m.isSynthetic()); + } + } + + /** + * Tests that {@link SyntheticConstructorDemo.NestedClass} contains a synthetic + * constructor. + */ + @Test + public void givenSyntheticConstructor_whenIsSinthetic_thenTrue() { + // Checks that the nested class contains exactly a synthetic + // constructor. + int syntheticConstructors = 0; + Constructor[] constructors = SyntheticConstructorDemo.NestedClass.class.getDeclaredConstructors(); + Assert.assertEquals("This class should contain only two constructors", 2, constructors.length); + + for (Constructor c : constructors) { + System.out.println("Constructor: " + c.getName() + ", isSynthetic: " + c.isSynthetic()); + + // Counts the synthetic constructors. + if (c.isSynthetic()) { + syntheticConstructors++; + } + } + + // Checks that there's exactly one synthetic constructor. + Assert.assertEquals(1, syntheticConstructors); + } + + /** + * Tests that {@link SyntheticFieldDemo.NestedClass} contains a synthetic field. + */ + @Test + public void givenSyntheticField_whenIsSinthetic_thenTrue() { + // This class should contain exactly one synthetic field. + Field[] fields = SyntheticFieldDemo.NestedClass.class.getDeclaredFields(); + Assert.assertEquals("This class should contain only one field", 1, fields.length); + + for (Field f : fields) { + System.out.println("Field: " + f.getName() + ", isSynthetic: " + f.isSynthetic()); + Assert.assertTrue("All the fields of this class should be synthetic", f.isSynthetic()); + } + } + + /** + * Tests that {@link BridgeMethodDemo} contains a synthetic bridge method. + */ + @Test + public void givenBridgeMethod_whenIsBridge_thenTrue() { + // This class should contain exactly one synthetic bridge method. + int syntheticMethods = 0; + Method[] methods = BridgeMethodDemo.class.getDeclaredMethods(); + for (Method m : methods) { + System.out.println( + "Method: " + m.getName() + ", isSynthetic: " + m.isSynthetic() + ", isBridge: " + m.isBridge()); + + // Counts the synthetic methods and checks that they are also bridge + // methods. + if (m.isSynthetic()) { + syntheticMethods++; + Assert.assertTrue("The synthetic method in this class should also be a bridge method", m.isBridge()); + } + } + + // Checks that there's exactly one synthetic bridge method. + Assert.assertEquals("There should be exactly 1 synthetic bridge method in this class", 1, syntheticMethods); + } + +} \ No newline at end of file