import java.lang.invoke.MethodHandles; import java.lang.invoke.VarHandle; class Main { void getInt() throws Throwable { MethodHandles.Lookup lookup = MethodHandles.lookup(); VarHandle handle = lookup.findVarHandle(Test.class, "n", int.class); Test instance = new Test(); Object nullArg = null; int exact = (int) handle.get(instance); Integer boxed = (Integer) handle.get(instance); Object object = (Object) handle.get(instance); String incompatible = (String) handle.get(instance); handle.get(instance, 1); handle.get(); handle.get(nullArg); handle.get(123); int exactV = (int) handle.getVolatile(instance); Integer boxedV = (Integer) handle.getVolatile(instance); Object objectV = (Object) handle.getVolatile(instance); String incompatibleV = (String) handle.getVolatile(instance); handle.getVolatile(instance, 1); handle.getVolatile(); handle.getVolatile(nullArg); handle.getVolatile(123); int exactO = (int) handle.getOpaque(instance); Integer boxedO = (Integer) handle.getOpaque(instance); Object objectO = (Object) handle.getOpaque(instance); String incompatibleO = (String) handle.getOpaque(instance); handle.getOpaque(instance, 1); handle.getOpaque(); handle.getOpaque(nullArg); handle.getOpaque(123); int exactA = (int) handle.getAcquire(instance); Integer boxedA = (Integer) handle.getAcquire(instance); Object objectA = (Object) handle.getAcquire(instance); String incompatibleA = (String) handle.getAcquire(instance); handle.getAcquire(instance, 1); handle.getAcquire(); handle.getAcquire(nullArg); handle.getAcquire(123); } void setInt() throws Throwable { MethodHandles.Lookup lookup = MethodHandles.lookup(); VarHandle handle = lookup.findVarHandle(Test.class, "n", int.class); Test instance = new Test(); Object nullArg = null; Object textArg = "abc"; Object numberArg = 123; handle.set(instance, 1); handle.set(instance, Integer.valueOf(2)); handle.set(instance, numberArg); handle.set(instance, textArg); handle.set(instance); handle.set(); handle.set(nullArg, 123); handle.set(instance, nullArg); handle.set(123, 42); handle.setVolatile(instance, 1); handle.setVolatile(instance, Integer.valueOf(2)); handle.setVolatile(instance, numberArg); handle.setVolatile(instance, textArg); handle.setVolatile(instance); handle.setVolatile(); handle.setVolatile(nullArg, 123); handle.setVolatile(instance, nullArg); handle.setVolatile(123, 42); handle.setOpaque(instance, 1); handle.setOpaque(instance, Integer.valueOf(2)); handle.setOpaque(instance, numberArg); handle.setOpaque(instance, textArg); handle.setOpaque(instance); handle.setOpaque(); handle.setOpaque(nullArg, 123); handle.setOpaque(instance, nullArg); handle.setOpaque(123, 42); handle.setRelease(instance, 1); handle.setRelease(instance, Integer.valueOf(2)); handle.setRelease(instance, numberArg); handle.setRelease(instance, textArg); handle.setRelease(instance); handle.setRelease(); handle.setRelease(nullArg, 123); handle.setRelease(instance, nullArg); handle.setRelease(123, 42); } void getStr() throws Throwable { MethodHandles.Lookup lookup = MethodHandles.lookup(); final VarHandle handle = lookup.findVarHandle(Test.class, "s", String.class); final Test instance = new Test(); final Object nullArg = null; String exact = (String) handle.get(instance); CharSequence parent = (CharSequence) handle.get(instance); Object object = (Object) handle.get(instance); Integer incompatible = (Integer) handle.get(instance); handle.get(instance, 1); handle.get(); handle.get(nullArg); handle.get(123); String exactV = (String) handle.getVolatile(instance); CharSequence parentV = (CharSequence) handle.getVolatile(instance); Object objectV = (Object) handle.getVolatile(instance); Integer incompatibleV = (Integer) handle.getVolatile(instance); handle.getVolatile(instance, 1); handle.getVolatile(); handle.getVolatile(nullArg); handle.getVolatile(123); String exactO = (String) handle.getOpaque(instance); CharSequence parentO = (CharSequence) handle.getOpaque(instance); Object objectO = (Object) handle.getOpaque(instance); Integer incompatibleO = (Integer) handle.getOpaque(instance); handle.getOpaque(instance, 1); handle.getOpaque(); handle.getOpaque(nullArg); handle.getOpaque("abc"); String exactA = (String) handle.getAcquire(instance); CharSequence parentA = (CharSequence) handle.getAcquire(instance); Object objectA = (Object) handle.getAcquire(instance); Integer incompatibleA = (Integer) handle.getAcquire(instance); handle.getAcquire(instance, 1); handle.getAcquire(); handle.getAcquire(nullArg); handle.getAcquire("abc"); } void setStr() throws Throwable { MethodHandles.Lookup lookup = MethodHandles.lookup(); final VarHandle handle = lookup.findVarHandle(Test.class, "s", String.class); final Test instance = new Test(); final Object nullArg = null; final Object textArg = "abc"; final Object numberArg = 3; handle.set(instance, "a"); handle.set(instance, charSequence()); handle.set(instance, textArg); handle.set(instance, nullArg); handle.set(instance, numberArg); handle.set(instance); handle.set(); handle.set(nullArg); handle.set("abc", "d"); handle.setVolatile(instance, "a"); handle.setVolatile(instance, charSequence()); handle.setVolatile(instance, textArg); handle.setVolatile(instance, nullArg); handle.setVolatile(instance, numberArg); handle.setVolatile(instance); handle.setVolatile(); handle.setVolatile(nullArg); handle.setVolatile("abc", "d"); handle.setOpaque(instance, "a"); handle.setOpaque(instance, charSequence()); handle.setOpaque(instance, textArg); handle.setOpaque(instance, nullArg); handle.setOpaque(instance, numberArg); handle.setOpaque(instance); handle.setOpaque(); handle.setOpaque(nullArg); handle.setOpaque("abc", "d"); handle.setRelease(instance, "a"); handle.setRelease(instance, charSequence()); handle.setRelease(instance, textArg); handle.setRelease(instance, nullArg); handle.setRelease(instance, numberArg); handle.setRelease(instance); handle.setRelease(); handle.setRelease(nullArg); handle.setRelease("abc", "d"); } private void getAndAddInt() throws Throwable { MethodHandles.Lookup lookup = MethodHandles.lookup(); VarHandle handle = lookup.findVarHandle(Test.class, "n", int.class); Test instance = new Test(); Object nullArg = null; int exact = (int) handle.getAndAdd(instance, 1); Integer boxed = (Integer) handle.getAndAdd(instance, 2); Object object = (Object) handle.getAndAdd(instance, 3); handle.getAndAdd(instance, 4); String incompatible = (String) handle.getAndAdd(instance, 0); int incompatibleArg = (int) handle.getAndSet(instance, "abc"); handle.getAndAdd(instance); handle.getAndAdd(); handle.getAndAdd(nullArg, 0); int wrongReceiver = (int)handle.getAndAdd(123, 42); int exactA = (int) handle.getAndAddAcquire(instance, 1); ; Integer boxedA = (Integer) handle.getAndAddAcquire(instance, 2); Object objectA = (Object) handle.getAndAddAcquire(instance, 3); handle.getAndAddAcquire(instance, 4); String incompatibleA = (String) handle.getAndAddAcquire(instance, 0); int incompatibleArgA = (int) handle.getAndSetAcquire(instance, "abc"); handle.getAndAddAcquire(instance); handle.getAndAddAcquire(); handle.getAndAddAcquire(nullArg, 0); int wrongReceiver = (int)handle.getAndAddAcquire(123, 42); int exactR = (int) handle.getAndAddRelease(instance, 1); ; Integer boxedR = (Integer) handle.getAndAddRelease(instance, 2); Object objectR = (Object) handle.getAndAddRelease(instance, 3); handle.getAndAddRelease(instance, 4); String incompatibleR = (String) handle.getAndAdd(instance, 0); int incompatibleArgR = (int) handle.getAndSetRelease(instance, "abc"); handle.getAndAddRelease(instance); handle.getAndAddRelease(); handle.getAndAddRelease(nullArg, 0); int wrongReceiverR = (int)handle.getAndAddRelease(123, 42); } private void getAndSetStr() throws Throwable { MethodHandles.Lookup lookup = MethodHandles.lookup(); final VarHandle handle = lookup.findVarHandle(Test.class, "s", String.class); final Test instance = new Test(); final Object nullArg = null; String exact = (String) handle.getAndSet(instance, "a"); CharSequence parent = (CharSequence) handle.getAndSet(instance, "b"); Object object = (Object) handle.getAndSet(instance, "c"); String subclassArg = (String) handle.getAndSet(instance, charSequence()); String withNullArg = (String) handle.getAndSet(instance, nullArg); handle.getAndSet(instance, "d"); Integer incompatible = (Integer) handle.getAndSet(instance, "e"); String incompatibleArg = (String) handle.getAndSet(instance, 123); handle.getAndSet(instance); handle.getAndSet(); handle.getAndSet(nullArg, "abc"); int wrongReceiver = (int)handle.getAndSet("abc", "e"); String exactA = (String) handle.getAndSetAcquire(instance, "a"); CharSequence parentA = (CharSequence) handle.getAndSetAcquire(instance, "b"); Object objectA = (Object) handle.getAndSetAcquire(instance, "c");; String subclassArgA = (String) handle.getAndSetAcquire(instance, charSequence()); String withNullArgA = (String) handle.getAndSetAcquire(instance, nullArg); handle.getAndSetAcquire(instance, "d"); Integer incompatibleA = (Integer) handle.getAndSetAcquire(instance, "e"); String incompatibleArgA = (String) handle.getAndSetAcquire(instance, 123); handle.getAndSetAcquire(instance); handle.getAndSetAcquire(); handle.getAndSetAcquire(nullArg, "abc"); int wrongReceiverA = (int)handle.getAndSetAcquire("abc", "e"); String exactR = (String) handle.getAndSetRelease(instance, "a"); CharSequence parentR = (CharSequence) handle.getAndSetRelease(instance, "b"); Object objectR = (Object) handle.getAndSetRelease(instance, "c");; String subclassArgR = (String) handle.getAndSetRelease(instance, charSequence()); String withNullArgR = (String) handle.getAndSetRelease(instance, nullArg); handle.getAndSetRelease(instance, "d"); Integer incompatibleR = (Integer) handle.getAndSetRelease(instance, "e"); String incompatibleArgR = (String) handle.getAndSetRelease(instance, 123); handle.getAndSetRelease(instance); handle.getAndSetRelease(); handle.getAndSetRelease(nullArg, "abc"); int wrongReceiverR = (int)handle.getAndSetRelease("abc", "e"); } void getAndBitwise() throws Throwable { MethodHandles.Lookup lookup = MethodHandles.lookup(); VarHandle handle = lookup.findVarHandle(Test.class, "n", int.class); Test instance = new Test(); int exactBitwiseAnd = (int) handle.getAndBitwiseAnd(instance, 1); int exactBitwiseAndA = (int) handle.getAndBitwiseAndAcquire(instance, 2); int exactBitwiseAndR = (int) handle.getAndBitwiseAndRelease(instance, 3); int wrongArgBitwiseAnd = (int) handle.getAndBitwiseAnd(instance, "a"); int wrongArgBitwiseAndA = (int) handle.getAndBitwiseAndAcquire(instance, "b"); int wrongArgBitwiseAndR = (int) handle.getAndBitwiseAndRelease(instance, "c"); String wrongResultBitwiseAnd = (String) handle.getAndBitwiseAnd(instance, 1); String wrongResultBitwiseAndA = (String) handle.getAndBitwiseAndAcquire(instance, 2); String wrongResultBitwiseAndR = (String) handle.getAndBitwiseAndRelease(instance, 3); int exactBitwiseOr = (int) handle.getAndBitwiseOr(instance, 1); int exactBitwiseOrA = (int) handle.getAndBitwiseOrAcquire(instance, 2); int exactBitwiseOrR = (int) handle.getAndBitwiseOrRelease(instance, 3); int wrongArgBitwiseOr = (int) handle.getAndBitwiseOr(instance, "a"); int wrongArgBitwiseOrA = (int) handle.getAndBitwiseOrAcquire(instance, "b"); int wrongArgBitwiseOrR = (int) handle.getAndBitwiseOrRelease(instance, "c"); String wrongResultBitwiseOr = (String) handle.getAndBitwiseOr(instance, 1); String wrongResultBitwiseOrA = (String) handle.getAndBitwiseOrAcquire(instance, 2); String wrongResultBitwiseOrR = (String) handle.getAndBitwiseOrRelease(instance, 3); int exactBitwiseXor = (int) handle.getAndBitwiseXor(instance, 1); int exactBitwiseXorA = (int) handle.getAndBitwiseXorAcquire(instance, 2); int exactBitwiseXorR = (int) handle.getAndBitwiseXorRelease(instance, 3); int wrongArgBitwiseXor = (int) handle.getAndBitwiseXor(instance, "a"); int wrongArgBitwiseXorA = (int) handle.getAndBitwiseXorAcquire(instance, "b"); int wrongArgBitwiseXorR = (int) handle.getAndBitwiseXorRelease(instance, "c"); String wrongResultBitwiseXor = (String) handle.getAndBitwiseXor(instance, 1); String wrongResultBitwiseXorA = (String) handle.getAndBitwiseXorAcquire(instance, 2); String wrongResultBitwiseXorR = (String) handle.getAndBitwiseXorRelease(instance, 3); } void compare() throws Throwable { MethodHandles.Lookup lookup = MethodHandles.lookup(); final VarHandle handle = lookup.findVarHandle(Test.class, "s", String.class); final Test instance = new Test(); boolean exactCAS = handle.compareAndSet(instance, "a", "b"); String exactCAE = (String)handle.compareAndExchange(instance, "a", "b"); String exactCAEA = (String)handle.compareAndExchangeAcquire(instance, "a", "b"); String exactCAER = (String)handle.compareAndExchangeRelease(instance, "a", "b"); boolean badArg2CAS = handle.compareAndSet(instance, 1, "b"); String badArg2CAE = (String)handle.compareAndExchange(instance, 2, "b"); String badArg2CAEa = (String)handle.compareAndExchangeAcquire(instance, 3, "b"); String badArg2CAEr = (String)handle.compareAndExchangeRelease(instance, 4, "b"); boolean badArg3CAS = handle.compareAndSet(instance, "a", 1); String badArg3CAE = (String)handle.compareAndExchange(instance, "a", 2); String badArg3CAEa = (String)handle.compareAndExchangeAcquire(instance, "a", 3); String badArg3CAEr = (String)handle.compareAndExchangeRelease(instance, "a", 4); Integer badResultCAE = (Integer)handle.compareAndExchange(instance, "a", "b"); Integer badResultCAEa = (Integer)handle.compareAndExchangeAcquire(instance, "a", "b"); Integer badResultCAEr = (Integer)handle.compareAndExchangeRelease(instance, "a", "b"); } void weakCompare() throws Throwable { MethodHandles.Lookup lookup = MethodHandles.lookup(); final VarHandle handle = lookup.findVarHandle(Test.class, "s", String.class); final Test instance = new Test(); boolean exactCAS = handle.weakCompareAndSet(instance, "a", "b"); boolean exactCASp = handle.weakCompareAndSetPlain(instance, "a", "b"); boolean exactCASa = handle.weakCompareAndSetAcquire(instance, "a", "b"); boolean exactCASr = handle.weakCompareAndSetRelease(instance, "a", "b"); boolean badArg2CAS = handle.weakCompareAndSet(instance, 1, "b"); boolean badArg2CASp = handle.weakCompareAndSetPlain(instance, 2, "b"); boolean badArg2CASa = handle.weakCompareAndSetAcquire(instance, 3, "b"); boolean badArg2CASr = handle.weakCompareAndSetRelease(instance, 4, "b"); boolean badArg3CAS = handle.weakCompareAndSet(instance, "a", 1); boolean badArg3CASp = handle.weakCompareAndSetPlain(instance, "a", 2); boolean badArg3CASa = handle.weakCompareAndSetAcquire(instance, "a", 3); boolean badArg3CASr = handle.weakCompareAndSetRelease(instance, "a", 4); } private static CharSequence charSequence() { return "abc"; } } class Test { public int n; public String s; }