--- a/jdk/src/java.base/share/classes/java/lang/invoke/MethodHandles.java Fri Apr 22 15:05:26 2016 +0200
+++ b/jdk/src/java.base/share/classes/java/lang/invoke/MethodHandles.java Fri Apr 22 15:05:54 2016 +0200
@@ -4476,16 +4476,24 @@
* @since 9
*/
public static MethodHandle countedLoop(MethodHandle start, MethodHandle end, MethodHandle init, MethodHandle body) {
- MethodHandle defaultResultHandle = init == null || init.type().returnType() == void.class ?
- zero(void.class) :
- identity(init.type().returnType());
- MethodHandle adaptedBody = body == null ? dropArguments(defaultResultHandle, 0, int.class) : body;
+ Class<?> resultType;
+ MethodHandle actualInit;
+ if (init == null) {
+ resultType = body == null ? void.class : body.type().returnType();
+ actualInit = empty(methodType(resultType));
+ } else {
+ resultType = init.type().returnType();
+ actualInit = init;
+ }
+ MethodHandle defaultResultHandle = resultType == void.class ? zero(void.class) : identity(resultType);
+ MethodHandle actualBody = body == null ? dropArguments(defaultResultHandle, 0, int.class) : body;
MethodHandle returnVar = dropArguments(defaultResultHandle, 0, int.class, int.class);
+ MethodHandle actualEnd = end == null ? constant(int.class, 0) : end;
MethodHandle[] indexVar = {start, MethodHandleImpl.getConstantHandle(MethodHandleImpl.MH_countedLoopStep)};
- MethodHandle[] loopLimit = {end, null, MethodHandleImpl.getConstantHandle(MethodHandleImpl.MH_countedLoopPred),
- returnVar};
- MethodHandle[] bodyClause = {init,
- filterArgument(dropArguments(adaptedBody, 1, int.class), 0,
+ MethodHandle[] loopLimit = {actualEnd, null,
+ MethodHandleImpl.getConstantHandle(MethodHandleImpl.MH_countedLoopPred), returnVar};
+ MethodHandle[] bodyClause = {actualInit,
+ filterArgument(dropArguments(actualBody, 1, int.class), 0,
MethodHandleImpl.getConstantHandle(MethodHandleImpl.MH_decrementCounter))};
return loop(indexVar, loopLimit, bodyClause);
}
--- a/jdk/test/java/lang/invoke/LoopCombinatorTest.java Fri Apr 22 15:05:26 2016 +0200
+++ b/jdk/test/java/lang/invoke/LoopCombinatorTest.java Fri Apr 22 15:05:54 2016 +0200
@@ -31,6 +31,7 @@
* @bug 8152667
* @bug 8153637
* @bug 8154751
+ * @bug 8154754
* @run testng/othervm -ea -esa test.java.lang.invoke.LoopCombinatorTest
*/
@@ -327,6 +328,74 @@
}
@Test
+ public static void testCountedLoopNullBody() throws Throwable {
+ MethodHandle h5 = MethodHandles.constant(int.class, 5);
+ MethodHandle h13 = MethodHandles.constant(int.class, 13);
+ MethodHandle loop = MethodHandles.countedLoop(h5, h13, null);
+ assertEquals(methodType(int.class), loop.type());
+ assertEquals(13, loop.invoke());
+ }
+
+ @Test
+ public static void testCountedLoopNullIterations() throws Throwable {
+ MethodHandle loop = MethodHandles.countedLoop(null, null, null);
+ assertEquals(methodType(void.class), loop.type());
+ loop.invoke();
+ }
+
+ @Test
+ public static void testCountedLoopNullInitAndBody() throws Throwable {
+ MethodHandle loop = MethodHandles.countedLoop(MethodHandles.constant(int.class, 5), null, null);
+ assertEquals(methodType(void.class), loop.type());
+ loop.invoke();
+ }
+
+ @DataProvider
+ static Object[][] countedLoopBodyParameters() {
+ return new Object[][] {
+ {methodType(String.class), methodType(String.class, int.class)},
+ {methodType(String.class, List.class), methodType(String.class, int.class)},
+ {methodType(String.class, List.class), methodType(String.class, int.class, String.class)}
+ };
+ }
+
+ @Test(dataProvider = "countedLoopBodyParameters")
+ public static void testCountedLoopBodyParameters(MethodType initType, MethodType bodyType) throws Throwable {
+ MethodHandle loop = MethodHandles.countedLoop(MethodHandles.constant(int.class, 5),
+ MethodHandles.empty(initType), MethodHandles.empty(bodyType));
+ assertEquals(initType, loop.type());
+ }
+
+ @DataProvider
+ static Object[][] countedLoopTypes() {
+ return new Object[][]{{void.class}, {int.class}, {Object.class}, {String.class}, {List.class}};
+ }
+
+ @Test(dataProvider = "countedLoopTypes")
+ public static void testCountedLoopBodyParametersNullInit(Class<?> t) throws Throwable {
+ MethodHandle loop = MethodHandles.countedLoop(MethodHandles.constant(int.class, 5), null,
+ MethodHandles.empty(methodType(t, int.class)));
+ assertEquals(methodType(t), loop.type());
+ loop.invoke();
+ }
+
+ @Test
+ public static void testCountedLoopStateDefinedByBody() throws Throwable {
+ MethodHandle loop = MethodHandles.countedLoop(MethodHandles.constant(int.class, 5), null, Counted.MH_stateBody);
+ assertEquals(Counted.MT_bodyDeterminesState, loop.type());
+ assertEquals("sssssnull01234", loop.invoke());
+ }
+
+ @Test
+ public static void testCountedLoopArgsDefinedByIterations() throws Throwable {
+ MethodHandle loop = MethodHandles.countedLoop(
+ MethodHandles.dropArguments(MethodHandles.constant(int.class, 3), 0, String.class),
+ null, Counted.MH_append);
+ assertEquals(Counted.MT_iterationsDefineArgs, loop.type());
+ assertEquals("hello012", loop.invoke("hello"));
+ }
+
+ @Test
public static void testCountedRangeLoop() throws Throwable {
// String s = "Lambdaman!"; for (int i = -5; i < 8; ++i) { s = "na " + s; } return s; => a well known theme
MethodHandle fitm5 = MethodHandles.dropArguments(Counted.MH_m5, 0, String.class);
@@ -839,6 +908,17 @@
return x + counter;
}
+ static String stateBody(int counter, String s) {
+ return "s" + s + counter;
+ }
+
+ static String append(int counter, String localState, String loopArg) {
+ if (null == localState) {
+ return loopArg + counter;
+ }
+ return localState + counter;
+ }
+
static final Class<Counted> COUNTED = Counted.class;
static final MethodType MT_start = methodType(String.class, String.class);
@@ -846,6 +926,8 @@
static final MethodType MT_stepUpdateArray = methodType(void.class, int.class, int[].class);
static final MethodType MT_printHello = methodType(void.class, int.class);
static final MethodType MT_addCounter = methodType(int.class, int.class, int.class);
+ static final MethodType MT_stateBody = methodType(String.class, int.class, String.class);
+ static final MethodType MT_append = methodType(String.class, int.class, String.class, String.class);
static final MethodHandle MH_13;
static final MethodHandle MH_m5;
@@ -855,11 +937,15 @@
static final MethodHandle MH_stepUpdateArray;
static final MethodHandle MH_printHello;
static final MethodHandle MH_addCounter;
+ static final MethodHandle MH_stateBody;
+ static final MethodHandle MH_append;
static final MethodType MT_counted = methodType(String.class, String.class);
static final MethodType MT_arrayCounted = methodType(void.class, int[].class);
static final MethodType MT_countedPrinting = methodType(void.class);
static final MethodType MT_counterInit = methodType(int.class);
+ static final MethodType MT_bodyDeterminesState = methodType(String.class);
+ static final MethodType MT_iterationsDefineArgs = methodType(String.class, String.class);
static {
try {
@@ -871,6 +957,8 @@
MH_stepUpdateArray = LOOKUP.findStatic(COUNTED, "stepUpdateArray", MT_stepUpdateArray);
MH_printHello = LOOKUP.findStatic(COUNTED, "printHello", MT_printHello);
MH_addCounter = LOOKUP.findStatic(COUNTED, "addCounter", MT_addCounter);
+ MH_stateBody = LOOKUP.findStatic(COUNTED, "stateBody", MT_stateBody);
+ MH_append = LOOKUP.findStatic(COUNTED, "append", MT_append);
} catch (Exception e) {
throw new ExceptionInInitializerError(e);
}