7013417: JSR 292 needs to support variadic method handle calls
Summary: Implement MH.asVarargsCollector, etc., and remove withTypeHandler.
Reviewed-by: twisti
/*
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
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* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
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* 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 sun.dyn;
import java.dyn.*;
import java.dyn.MethodHandles.Lookup;
import java.util.logging.Level;
import java.util.logging.Logger;
import sun.dyn.util.VerifyType;
import java.dyn.NoAccessException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import sun.dyn.empty.Empty;
import sun.dyn.util.ValueConversions;
import sun.dyn.util.Wrapper;
import sun.misc.Unsafe;
import static sun.dyn.MemberName.newIllegalArgumentException;
import static sun.dyn.MemberName.newNoAccessException;
import static sun.dyn.MemberName.uncaughtException;
/**
* Base class for method handles, containing JVM-specific fields and logic.
* TO DO: It should not be a base class.
* @author jrose
*/
public abstract class MethodHandleImpl {
// Fields which really belong in MethodHandle:
private byte vmentry; // adapter stub or method entry point
//private int vmslots; // optionally, hoist type.form.vmslots
protected Object vmtarget; // VM-specific, class-specific target value
//MethodType type; // defined in MethodHandle
// TO DO: vmtarget should be invisible to Java, since the JVM puts internal
// managed pointers into it. Making it visible exposes it to debuggers,
// which can cause errors when they treat the pointer as an Object.
// These two dummy fields are present to force 'I' and 'J' signatures
// into this class's constant pool, so they can be transferred
// to vmentry when this class is loaded.
static final int INT_FIELD = 0;
static final long LONG_FIELD = 0;
/** Access methods for the internals of MethodHandle, supplied to
* MethodHandleImpl as a trusted agent.
*/
static public interface MethodHandleFriend {
void initType(MethodHandle mh, MethodType type);
}
public static void setMethodHandleFriend(Access token, MethodHandleFriend am) {
Access.check(token);
if (METHOD_HANDLE_FRIEND != null)
throw new InternalError(); // just once
METHOD_HANDLE_FRIEND = am;
}
static private MethodHandleFriend METHOD_HANDLE_FRIEND;
// NOT public
static void initType(MethodHandle mh, MethodType type) {
METHOD_HANDLE_FRIEND.initType(mh, type);
}
// type is defined in java.dyn.MethodHandle, which is platform-independent
// vmentry (a void* field) is used *only* by by the JVM.
// The JVM adjusts its type to int or long depending on system wordsize.
// Since it is statically typed as neither int nor long, it is impossible
// to use this field from Java bytecode. (Please don't try to, either.)
// The vmentry is an assembly-language stub which is jumped to
// immediately after the method type is verified.
// For a direct MH, this stub loads the vmtarget's entry point
// and jumps to it.
/**
* VM-based method handles must have a security token.
* This security token can only be obtained by trusted code.
* Do not create method handles directly; use factory methods.
*/
public MethodHandleImpl(Access token) {
Access.check(token);
}
/** Initialize the method type form to participate in JVM calls.
* This is done once for each erased type.
*/
public static void init(Access token, MethodType self) {
Access.check(token);
if (MethodHandleNatives.JVM_SUPPORT)
MethodHandleNatives.init(self);
}
/// Factory methods to create method handles:
private static final MemberName.Factory LOOKUP = MemberName.Factory.INSTANCE;
static private Lookup IMPL_LOOKUP_INIT;
public static void initLookup(Access token, Lookup lookup) {
Access.check(token);
if (IMPL_LOOKUP_INIT != null)
throw new InternalError();
IMPL_LOOKUP_INIT = lookup;
}
public static Lookup getLookup(Access token) {
Access.check(token);
return IMPL_LOOKUP;
}
static {
// Force initialization of Lookup, so it calls us back as initLookup:
MethodHandles.publicLookup();
if (IMPL_LOOKUP_INIT == null)
throw new InternalError();
}
public static void initStatics() {
// Trigger preceding sequence.
}
/** Shared secret with MethodHandles.Lookup, a copy of Lookup.IMPL_LOOKUP. */
static final Lookup IMPL_LOOKUP = IMPL_LOOKUP_INIT;
/** Look up a given method.
* Callable only from java.dyn and related packages.
* <p>
* The resulting method handle type will be of the given type,
* with a receiver type {@code rcvc} prepended if the member is not static.
* <p>
* Access checks are made as of the given lookup class.
* In particular, if the method is protected and {@code defc} is in a
* different package from the lookup class, then {@code rcvc} must be
* the lookup class or a subclass.
* @param token Proof that the lookup class has access to this package.
* @param member Resolved method or constructor to call.
* @param name Name of the desired method.
* @param rcvc Receiver type of desired non-static method (else null)
* @param doDispatch whether the method handle will test the receiver type
* @param lookupClass access-check relative to this class
* @return a direct handle to the matching method
* @throws NoAccessException if the given method cannot be accessed by the lookup class
*/
public static
MethodHandle findMethod(Access token, MemberName method,
boolean doDispatch, Class<?> lookupClass) throws NoAccessException {
Access.check(token); // only trusted calls
MethodType mtype = method.getMethodType();
if (!method.isStatic()) {
// adjust the advertised receiver type to be exactly the one requested
// (in the case of invokespecial, this will be the calling class)
Class<?> recvType = method.getDeclaringClass();
mtype = mtype.insertParameterTypes(0, recvType);
}
DirectMethodHandle mh = new DirectMethodHandle(mtype, method, doDispatch, lookupClass);
if (!mh.isValid())
throw newNoAccessException(method, lookupClass);
assert(mh.type() == mtype);
if (!method.isVarargs())
return mh;
else
return mh.asVarargsCollector(mtype.parameterType(mtype.parameterCount()-1));
}
public static
MethodHandle makeAllocator(Access token, MethodHandle rawConstructor) {
Access.check(token);
MethodType rawConType = rawConstructor.type();
// Wrap the raw (unsafe) constructor with the allocation of a suitable object.
MethodHandle allocator
= AllocateObject.make(token, rawConType.parameterType(0), rawConstructor);
assert(allocator.type()
.equals(rawConType.dropParameterTypes(0, 1).changeReturnType(rawConType.parameterType(0))));
return allocator;
}
static final class AllocateObject<C> extends BoundMethodHandle {
private static final Unsafe unsafe = Unsafe.getUnsafe();
private final Class<C> allocateClass;
private final MethodHandle rawConstructor;
private AllocateObject(MethodHandle invoker,
Class<C> allocateClass, MethodHandle rawConstructor) {
super(Access.TOKEN, invoker);
this.allocateClass = allocateClass;
this.rawConstructor = rawConstructor;
}
static MethodHandle make(Access token,
Class<?> allocateClass, MethodHandle rawConstructor) {
Access.check(token);
MethodType rawConType = rawConstructor.type();
assert(rawConType.parameterType(0) == allocateClass);
MethodType newType = rawConType.dropParameterTypes(0, 1).changeReturnType(allocateClass);
int nargs = rawConType.parameterCount() - 1;
if (nargs < INVOKES.length) {
MethodHandle invoke = INVOKES[nargs];
MethodType conType = CON_TYPES[nargs];
MethodHandle gcon = convertArguments(token, rawConstructor, conType, rawConType, null);
if (gcon == null) return null;
MethodHandle galloc = new AllocateObject(invoke, allocateClass, gcon);
assert(galloc.type() == newType.generic());
return convertArguments(token, galloc, newType, galloc.type(), null);
} else {
MethodHandle invoke = VARARGS_INVOKE;
MethodType conType = CON_TYPES[nargs];
MethodHandle gcon = spreadArguments(token, rawConstructor, conType, 1);
if (gcon == null) return null;
MethodHandle galloc = new AllocateObject(invoke, allocateClass, gcon);
return collectArguments(token, galloc, newType, 1, null);
}
}
@Override
public String toString() {
return addTypeString(allocateClass.getSimpleName(), this);
}
@SuppressWarnings("unchecked")
private C allocate() throws InstantiationException {
return (C) unsafe.allocateInstance(allocateClass);
}
private C invoke_V(Object... av) throws Throwable {
C obj = allocate();
rawConstructor.invokeExact((Object)obj, av);
return obj;
}
private C invoke_L0() throws Throwable {
C obj = allocate();
rawConstructor.invokeExact((Object)obj);
return obj;
}
private C invoke_L1(Object a0) throws Throwable {
C obj = allocate();
rawConstructor.invokeExact((Object)obj, a0);
return obj;
}
private C invoke_L2(Object a0, Object a1) throws Throwable {
C obj = allocate();
rawConstructor.invokeExact((Object)obj, a0, a1);
return obj;
}
private C invoke_L3(Object a0, Object a1, Object a2) throws Throwable {
C obj = allocate();
rawConstructor.invokeExact((Object)obj, a0, a1, a2);
return obj;
}
private C invoke_L4(Object a0, Object a1, Object a2, Object a3) throws Throwable {
C obj = allocate();
rawConstructor.invokeExact((Object)obj, a0, a1, a2, a3);
return obj;
}
private C invoke_L5(Object a0, Object a1, Object a2, Object a3, Object a4) throws Throwable {
C obj = allocate();
rawConstructor.invokeExact((Object)obj, a0, a1, a2, a3, a4);
return obj;
}
private C invoke_L6(Object a0, Object a1, Object a2, Object a3, Object a4, Object a5) throws Throwable {
C obj = allocate();
rawConstructor.invokeExact((Object)obj, a0, a1, a2, a3, a4, a5);
return obj;
}
private C invoke_L7(Object a0, Object a1, Object a2, Object a3, Object a4, Object a5, Object a6) throws Throwable {
C obj = allocate();
rawConstructor.invokeExact((Object)obj, a0, a1, a2, a3, a4, a5, a6);
return obj;
}
private C invoke_L8(Object a0, Object a1, Object a2, Object a3, Object a4, Object a5, Object a6, Object a7) throws Throwable {
C obj = allocate();
rawConstructor.invokeExact((Object)obj, a0, a1, a2, a3, a4, a5, a6, a7);
return obj;
}
static MethodHandle[] makeInvokes() {
ArrayList<MethodHandle> invokes = new ArrayList<MethodHandle>();
MethodHandles.Lookup lookup = IMPL_LOOKUP;
for (;;) {
int nargs = invokes.size();
String name = "invoke_L"+nargs;
MethodHandle invoke = null;
try {
invoke = lookup.findVirtual(AllocateObject.class, name, MethodType.genericMethodType(nargs));
} catch (NoAccessException ex) {
}
if (invoke == null) break;
invokes.add(invoke);
}
assert(invokes.size() == 9); // current number of methods
return invokes.toArray(new MethodHandle[0]);
};
static final MethodHandle[] INVOKES = makeInvokes();
// For testing use this:
//static final MethodHandle[] INVOKES = Arrays.copyOf(makeInvokes(), 2);
static final MethodHandle VARARGS_INVOKE;
static {
try {
VARARGS_INVOKE = IMPL_LOOKUP.findVirtual(AllocateObject.class, "invoke_V", MethodType.genericMethodType(0, true));
} catch (NoAccessException ex) {
throw uncaughtException(ex);
}
}
// Corresponding generic constructor types:
static final MethodType[] CON_TYPES = new MethodType[INVOKES.length];
static {
for (int i = 0; i < INVOKES.length; i++)
CON_TYPES[i] = makeConType(INVOKES[i]);
}
static final MethodType VARARGS_CON_TYPE = makeConType(VARARGS_INVOKE);
static MethodType makeConType(MethodHandle invoke) {
MethodType invType = invoke.type();
return invType.changeParameterType(0, Object.class).changeReturnType(void.class);
}
}
public static
MethodHandle accessField(Access token,
MemberName member, boolean isSetter,
Class<?> lookupClass) {
Access.check(token);
// Use sun. misc.Unsafe to dig up the dirt on the field.
MethodHandle mh = new FieldAccessor(token, member, isSetter);
return mh;
}
public static
MethodHandle accessArrayElement(Access token,
Class<?> arrayClass, boolean isSetter) {
Access.check(token);
if (!arrayClass.isArray())
throw newIllegalArgumentException("not an array: "+arrayClass);
Class<?> elemClass = arrayClass.getComponentType();
MethodHandle[] mhs = FieldAccessor.ARRAY_CACHE.get(elemClass);
if (mhs == null) {
if (!FieldAccessor.doCache(elemClass))
return FieldAccessor.ahandle(arrayClass, isSetter);
mhs = new MethodHandle[] {
FieldAccessor.ahandle(arrayClass, false),
FieldAccessor.ahandle(arrayClass, true)
};
if (mhs[0].type().parameterType(0) == Class.class) {
mhs[0] = MethodHandles.insertArguments(mhs[0], 0, elemClass);
mhs[1] = MethodHandles.insertArguments(mhs[1], 0, elemClass);
}
synchronized (FieldAccessor.ARRAY_CACHE) {} // memory barrier
FieldAccessor.ARRAY_CACHE.put(elemClass, mhs);
}
return mhs[isSetter ? 1 : 0];
}
static final class FieldAccessor<C,V> extends BoundMethodHandle {
private static final Unsafe unsafe = Unsafe.getUnsafe();
final Object base; // for static refs only
final long offset;
final String name;
public FieldAccessor(Access token, MemberName field, boolean isSetter) {
super(Access.TOKEN, fhandle(field.getDeclaringClass(), field.getFieldType(), isSetter, field.isStatic()));
this.offset = (long) field.getVMIndex(token);
this.name = field.getName();
this.base = staticBase(field);
}
public String toString() { return addTypeString(name, this); }
int getFieldI(C obj) { return unsafe.getInt(obj, offset); }
void setFieldI(C obj, int x) { unsafe.putInt(obj, offset, x); }
long getFieldJ(C obj) { return unsafe.getLong(obj, offset); }
void setFieldJ(C obj, long x) { unsafe.putLong(obj, offset, x); }
float getFieldF(C obj) { return unsafe.getFloat(obj, offset); }
void setFieldF(C obj, float x) { unsafe.putFloat(obj, offset, x); }
double getFieldD(C obj) { return unsafe.getDouble(obj, offset); }
void setFieldD(C obj, double x) { unsafe.putDouble(obj, offset, x); }
boolean getFieldZ(C obj) { return unsafe.getBoolean(obj, offset); }
void setFieldZ(C obj, boolean x) { unsafe.putBoolean(obj, offset, x); }
byte getFieldB(C obj) { return unsafe.getByte(obj, offset); }
void setFieldB(C obj, byte x) { unsafe.putByte(obj, offset, x); }
short getFieldS(C obj) { return unsafe.getShort(obj, offset); }
void setFieldS(C obj, short x) { unsafe.putShort(obj, offset, x); }
char getFieldC(C obj) { return unsafe.getChar(obj, offset); }
void setFieldC(C obj, char x) { unsafe.putChar(obj, offset, x); }
@SuppressWarnings("unchecked")
V getFieldL(C obj) { return (V) unsafe.getObject(obj, offset); }
@SuppressWarnings("unchecked")
void setFieldL(C obj, V x) { unsafe.putObject(obj, offset, x); }
// cast (V) is OK here, since we wrap convertArguments around the MH.
static Object staticBase(MemberName field) {
if (!field.isStatic()) return null;
Class c = field.getDeclaringClass();
java.lang.reflect.Field f;
try {
// FIXME: Should not have to create 'f' to get this value.
f = c.getDeclaredField(field.getName());
return unsafe.staticFieldBase(f);
} catch (Exception ee) {
throw uncaughtException(ee);
}
}
int getStaticI() { return unsafe.getInt(base, offset); }
void setStaticI(int x) { unsafe.putInt(base, offset, x); }
long getStaticJ() { return unsafe.getLong(base, offset); }
void setStaticJ(long x) { unsafe.putLong(base, offset, x); }
float getStaticF() { return unsafe.getFloat(base, offset); }
void setStaticF(float x) { unsafe.putFloat(base, offset, x); }
double getStaticD() { return unsafe.getDouble(base, offset); }
void setStaticD(double x) { unsafe.putDouble(base, offset, x); }
boolean getStaticZ() { return unsafe.getBoolean(base, offset); }
void setStaticZ(boolean x) { unsafe.putBoolean(base, offset, x); }
byte getStaticB() { return unsafe.getByte(base, offset); }
void setStaticB(byte x) { unsafe.putByte(base, offset, x); }
short getStaticS() { return unsafe.getShort(base, offset); }
void setStaticS(short x) { unsafe.putShort(base, offset, x); }
char getStaticC() { return unsafe.getChar(base, offset); }
void setStaticC(char x) { unsafe.putChar(base, offset, x); }
V getStaticL() { return (V) unsafe.getObject(base, offset); }
void setStaticL(V x) { unsafe.putObject(base, offset, x); }
static String fname(Class<?> vclass, boolean isSetter, boolean isStatic) {
String stem;
if (!isStatic)
stem = (!isSetter ? "getField" : "setField");
else
stem = (!isSetter ? "getStatic" : "setStatic");
return stem + Wrapper.basicTypeChar(vclass);
}
static MethodType ftype(Class<?> cclass, Class<?> vclass, boolean isSetter, boolean isStatic) {
MethodType type;
if (!isStatic) {
if (!isSetter)
return MethodType.methodType(vclass, cclass);
else
return MethodType.methodType(void.class, cclass, vclass);
} else {
if (!isSetter)
return MethodType.methodType(vclass);
else
return MethodType.methodType(void.class, vclass);
}
}
static MethodHandle fhandle(Class<?> cclass, Class<?> vclass, boolean isSetter, boolean isStatic) {
String name = FieldAccessor.fname(vclass, isSetter, isStatic);
if (cclass.isPrimitive()) throw newIllegalArgumentException("primitive "+cclass);
Class<?> ecclass = Object.class; //erase this type
Class<?> evclass = vclass;
if (!evclass.isPrimitive()) evclass = Object.class;
MethodType type = FieldAccessor.ftype(ecclass, evclass, isSetter, isStatic);
MethodHandle mh;
try {
mh = IMPL_LOOKUP.findVirtual(FieldAccessor.class, name, type);
} catch (NoAccessException ex) {
throw uncaughtException(ex);
}
if (evclass != vclass || (!isStatic && ecclass != cclass)) {
MethodType strongType = FieldAccessor.ftype(cclass, vclass, isSetter, isStatic);
strongType = strongType.insertParameterTypes(0, FieldAccessor.class);
mh = MethodHandles.convertArguments(mh, strongType);
}
return mh;
}
/// Support for array element access
static final HashMap<Class<?>, MethodHandle[]> ARRAY_CACHE =
new HashMap<Class<?>, MethodHandle[]>();
// FIXME: Cache on the classes themselves, not here.
static boolean doCache(Class<?> elemClass) {
if (elemClass.isPrimitive()) return true;
ClassLoader cl = elemClass.getClassLoader();
return cl == null || cl == ClassLoader.getSystemClassLoader();
}
static int getElementI(int[] a, int i) { return a[i]; }
static void setElementI(int[] a, int i, int x) { a[i] = x; }
static long getElementJ(long[] a, int i) { return a[i]; }
static void setElementJ(long[] a, int i, long x) { a[i] = x; }
static float getElementF(float[] a, int i) { return a[i]; }
static void setElementF(float[] a, int i, float x) { a[i] = x; }
static double getElementD(double[] a, int i) { return a[i]; }
static void setElementD(double[] a, int i, double x) { a[i] = x; }
static boolean getElementZ(boolean[] a, int i) { return a[i]; }
static void setElementZ(boolean[] a, int i, boolean x) { a[i] = x; }
static byte getElementB(byte[] a, int i) { return a[i]; }
static void setElementB(byte[] a, int i, byte x) { a[i] = x; }
static short getElementS(short[] a, int i) { return a[i]; }
static void setElementS(short[] a, int i, short x) { a[i] = x; }
static char getElementC(char[] a, int i) { return a[i]; }
static void setElementC(char[] a, int i, char x) { a[i] = x; }
static Object getElementL(Object[] a, int i) { return a[i]; }
static void setElementL(Object[] a, int i, Object x) { a[i] = x; }
static <V> V getElementL(Class<V[]> aclass, V[] a, int i) { return aclass.cast(a)[i]; }
static <V> void setElementL(Class<V[]> aclass, V[] a, int i, V x) { aclass.cast(a)[i] = x; }
static String aname(Class<?> aclass, boolean isSetter) {
Class<?> vclass = aclass.getComponentType();
if (vclass == null) throw new IllegalArgumentException();
return (!isSetter ? "getElement" : "setElement") + Wrapper.basicTypeChar(vclass);
}
static MethodType atype(Class<?> aclass, boolean isSetter) {
Class<?> vclass = aclass.getComponentType();
if (!isSetter)
return MethodType.methodType(vclass, aclass, int.class);
else
return MethodType.methodType(void.class, aclass, int.class, vclass);
}
static MethodHandle ahandle(Class<?> aclass, boolean isSetter) {
Class<?> vclass = aclass.getComponentType();
String name = FieldAccessor.aname(aclass, isSetter);
Class<?> caclass = null;
if (!vclass.isPrimitive() && vclass != Object.class) {
caclass = aclass;
aclass = Object[].class;
vclass = Object.class;
}
MethodType type = FieldAccessor.atype(aclass, isSetter);
if (caclass != null)
type = type.insertParameterTypes(0, Class.class);
MethodHandle mh;
try {
mh = IMPL_LOOKUP.findStatic(FieldAccessor.class, name, type);
} catch (NoAccessException ex) {
throw uncaughtException(ex);
}
if (caclass != null) {
MethodType strongType = FieldAccessor.atype(caclass, isSetter);
mh = MethodHandles.insertArguments(mh, 0, caclass);
mh = MethodHandles.convertArguments(mh, strongType);
}
return mh;
}
}
/** Bind a predetermined first argument to the given direct method handle.
* Callable only from MethodHandles.
* @param token Proof that the caller has access to this package.
* @param target Any direct method handle.
* @param receiver Receiver (or first static method argument) to pre-bind.
* @return a BoundMethodHandle for the given DirectMethodHandle, or null if it does not exist
*/
public static
MethodHandle bindReceiver(Access token,
MethodHandle target, Object receiver) {
Access.check(token);
if (target instanceof AdapterMethodHandle &&
((AdapterMethodHandle)target).conversionOp() == MethodHandleNatives.Constants.OP_RETYPE_ONLY
) {
Object info = MethodHandleNatives.getTargetInfo(target);
if (info instanceof DirectMethodHandle) {
DirectMethodHandle dmh = (DirectMethodHandle) info;
if (receiver == null ||
dmh.type().parameterType(0).isAssignableFrom(receiver.getClass())) {
MethodHandle bmh = new BoundMethodHandle(dmh, receiver, 0);
MethodType newType = target.type().dropParameterTypes(0, 1);
return convertArguments(token, bmh, newType, bmh.type(), null);
}
}
}
if (target instanceof DirectMethodHandle)
return new BoundMethodHandle((DirectMethodHandle)target, receiver, 0);
return null; // let caller try something else
}
/** Bind a predetermined argument to the given arbitrary method handle.
* Callable only from MethodHandles.
* @param token Proof that the caller has access to this package.
* @param target Any method handle.
* @param receiver Argument (which can be a boxed primitive) to pre-bind.
* @return a suitable BoundMethodHandle
*/
public static
MethodHandle bindArgument(Access token,
MethodHandle target, int argnum, Object receiver) {
Access.check(token);
return new BoundMethodHandle(target, receiver, argnum);
}
public static MethodHandle convertArguments(Access token,
MethodHandle target,
MethodType newType,
MethodType oldType,
int[] permutationOrNull) {
Access.check(token);
assert(oldType.parameterCount() == target.type().parameterCount());
if (permutationOrNull != null) {
int outargs = oldType.parameterCount(), inargs = newType.parameterCount();
if (permutationOrNull.length != outargs)
throw newIllegalArgumentException("wrong number of arguments in permutation");
// Make the individual outgoing argument types match up first.
Class<?>[] callTypeArgs = new Class<?>[outargs];
for (int i = 0; i < outargs; i++)
callTypeArgs[i] = newType.parameterType(permutationOrNull[i]);
MethodType callType = MethodType.methodType(oldType.returnType(), callTypeArgs);
target = convertArguments(token, target, callType, oldType, null);
assert(target != null);
oldType = target.type();
List<Integer> goal = new ArrayList<Integer>(); // i*TOKEN
List<Integer> state = new ArrayList<Integer>(); // i*TOKEN
List<Integer> drops = new ArrayList<Integer>(); // not tokens
List<Integer> dups = new ArrayList<Integer>(); // not tokens
final int TOKEN = 10; // to mark items which are symbolic only
// state represents the argument values coming into target
for (int i = 0; i < outargs; i++) {
state.add(permutationOrNull[i] * TOKEN);
}
// goal represents the desired state
for (int i = 0; i < inargs; i++) {
if (state.contains(i * TOKEN)) {
goal.add(i * TOKEN);
} else {
// adapter must initially drop all unused arguments
drops.add(i);
}
}
// detect duplications
while (state.size() > goal.size()) {
for (int i2 = 0; i2 < state.size(); i2++) {
int arg1 = state.get(i2);
int i1 = state.indexOf(arg1);
if (i1 != i2) {
// found duplicate occurrence at i2
int arg2 = (inargs++) * TOKEN;
state.set(i2, arg2);
dups.add(goal.indexOf(arg1));
goal.add(arg2);
}
}
}
assert(state.size() == goal.size());
int size = goal.size();
while (!state.equals(goal)) {
// Look for a maximal sequence of adjacent misplaced arguments,
// and try to rotate them into place.
int bestRotArg = -10 * TOKEN, bestRotLen = 0;
int thisRotArg = -10 * TOKEN, thisRotLen = 0;
for (int i = 0; i < size; i++) {
int arg = state.get(i);
// Does this argument match the current run?
if (arg == thisRotArg + TOKEN) {
thisRotArg = arg;
thisRotLen += 1;
if (bestRotLen < thisRotLen) {
bestRotLen = thisRotLen;
bestRotArg = thisRotArg;
}
} else {
// The old sequence (if any) stops here.
thisRotLen = 0;
thisRotArg = -10 * TOKEN;
// But maybe a new one starts here also.
int wantArg = goal.get(i);
final int MAX_ARG_ROTATION = AdapterMethodHandle.MAX_ARG_ROTATION;
if (arg != wantArg &&
arg >= wantArg - TOKEN * MAX_ARG_ROTATION &&
arg <= wantArg + TOKEN * MAX_ARG_ROTATION) {
thisRotArg = arg;
thisRotLen = 1;
}
}
}
if (bestRotLen >= 2) {
// Do a rotation if it can improve argument positioning
// by at least 2 arguments. This is not always optimal,
// but it seems to catch common cases.
int dstEnd = state.indexOf(bestRotArg);
int srcEnd = goal.indexOf(bestRotArg);
int rotBy = dstEnd - srcEnd;
int dstBeg = dstEnd - (bestRotLen - 1);
int srcBeg = srcEnd - (bestRotLen - 1);
assert((dstEnd | dstBeg | srcEnd | srcBeg) >= 0); // no negs
// Make a span which covers both source and destination.
int rotBeg = Math.min(dstBeg, srcBeg);
int rotEnd = Math.max(dstEnd, srcEnd);
int score = 0;
for (int i = rotBeg; i <= rotEnd; i++) {
if ((int)state.get(i) != (int)goal.get(i))
score += 1;
}
List<Integer> rotSpan = state.subList(rotBeg, rotEnd+1);
Collections.rotate(rotSpan, -rotBy); // reverse direction
for (int i = rotBeg; i <= rotEnd; i++) {
if ((int)state.get(i) != (int)goal.get(i))
score -= 1;
}
if (score >= 2) {
// Improved at least two argument positions. Do it.
List<Class<?>> ptypes = Arrays.asList(oldType.parameterArray());
Collections.rotate(ptypes.subList(rotBeg, rotEnd+1), -rotBy);
MethodType rotType = MethodType.methodType(oldType.returnType(), ptypes);
MethodHandle nextTarget
= AdapterMethodHandle.makeRotateArguments(token, rotType, target,
rotBeg, rotSpan.size(), rotBy);
if (nextTarget != null) {
//System.out.println("Rot: "+rotSpan+" by "+rotBy);
target = nextTarget;
oldType = rotType;
continue;
}
}
// Else de-rotate, and drop through to the swap-fest.
Collections.rotate(rotSpan, rotBy);
}
// Now swap like the wind!
List<Class<?>> ptypes = Arrays.asList(oldType.parameterArray());
for (int i = 0; i < size; i++) {
// What argument do I want here?
int arg = goal.get(i);
if (arg != state.get(i)) {
// Where is it now?
int j = state.indexOf(arg);
Collections.swap(ptypes, i, j);
MethodType swapType = MethodType.methodType(oldType.returnType(), ptypes);
target = AdapterMethodHandle.makeSwapArguments(token, swapType, target, i, j);
if (target == null) throw newIllegalArgumentException("cannot swap");
assert(target.type() == swapType);
oldType = swapType;
Collections.swap(state, i, j);
}
}
// One pass of swapping must finish the job.
assert(state.equals(goal));
}
while (!dups.isEmpty()) {
// Grab a contiguous trailing sequence of dups.
int grab = dups.size() - 1;
int dupArgPos = dups.get(grab), dupArgCount = 1;
while (grab - 1 >= 0) {
int dup0 = dups.get(grab - 1);
if (dup0 != dupArgPos - 1) break;
dupArgPos -= 1;
dupArgCount += 1;
grab -= 1;
}
//if (dupArgCount > 1) System.out.println("Dup: "+dups.subList(grab, dups.size()));
dups.subList(grab, dups.size()).clear();
// In the new target type drop that many args from the tail:
List<Class<?>> ptypes = oldType.parameterList();
ptypes = ptypes.subList(0, ptypes.size() - dupArgCount);
MethodType dupType = MethodType.methodType(oldType.returnType(), ptypes);
target = AdapterMethodHandle.makeDupArguments(token, dupType, target, dupArgPos, dupArgCount);
if (target == null)
throw newIllegalArgumentException("cannot dup");
oldType = target.type();
}
while (!drops.isEmpty()) {
// Grab a contiguous initial sequence of drops.
int dropArgPos = drops.get(0), dropArgCount = 1;
while (dropArgCount < drops.size()) {
int drop1 = drops.get(dropArgCount);
if (drop1 != dropArgPos + dropArgCount) break;
dropArgCount += 1;
}
//if (dropArgCount > 1) System.out.println("Drop: "+drops.subList(0, dropArgCount));
drops.subList(0, dropArgCount).clear();
List<Class<?>> dropTypes = newType.parameterList()
.subList(dropArgPos, dropArgPos + dropArgCount);
MethodType dropType = oldType.insertParameterTypes(dropArgPos, dropTypes);
target = AdapterMethodHandle.makeDropArguments(token, dropType, target, dropArgPos, dropArgCount);
if (target == null) throw newIllegalArgumentException("cannot drop");
oldType = target.type();
}
}
if (newType == oldType)
return target;
if (oldType.parameterCount() != newType.parameterCount())
throw newIllegalArgumentException("mismatched parameter count");
MethodHandle res = AdapterMethodHandle.makePairwiseConvert(token, newType, target);
if (res != null)
return res;
int argc = oldType.parameterCount();
// The JVM can't do it directly, so fill in the gap with a Java adapter.
// TO DO: figure out what to put here from case-by-case experience
// Use a heavier method: Convert all the arguments to Object,
// then back to the desired types. We might have to use Java-based
// method handles to do this.
MethodType objType = MethodType.genericMethodType(argc);
MethodHandle objTarget = AdapterMethodHandle.makePairwiseConvert(token, objType, target);
if (objTarget == null)
objTarget = FromGeneric.make(target);
res = AdapterMethodHandle.makePairwiseConvert(token, newType, objTarget);
if (res != null)
return res;
return ToGeneric.make(newType, objTarget);
}
public static MethodHandle spreadArguments(Access token,
MethodHandle target,
MethodType newType,
int spreadArg) {
Access.check(token);
// TO DO: maybe allow the restarg to be Object and implicitly cast to Object[]
MethodType oldType = target.type();
// spread the last argument of newType to oldType
int spreadCount = oldType.parameterCount() - spreadArg;
Class<Object[]> spreadArgType = Object[].class;
MethodHandle res = AdapterMethodHandle.makeSpreadArguments(token, newType, target, spreadArgType, spreadArg, spreadCount);
if (res != null)
return res;
// try an intermediate adapter
Class<?> spreadType = null;
if (spreadArg < 0 || spreadArg >= newType.parameterCount()
|| !VerifyType.isSpreadArgType(spreadType = newType.parameterType(spreadArg)))
throw newIllegalArgumentException("no restarg in "+newType);
Class<?>[] ptypes = oldType.parameterArray();
for (int i = 0; i < spreadCount; i++)
ptypes[spreadArg + i] = VerifyType.spreadArgElementType(spreadType, i);
MethodType midType = MethodType.methodType(newType.returnType(), ptypes);
// after spreading, some arguments may need further conversion
MethodHandle target2 = convertArguments(token, target, midType, oldType, null);
if (target2 == null)
throw new UnsupportedOperationException("NYI: convert "+midType+" =calls=> "+oldType);
res = AdapterMethodHandle.makeSpreadArguments(token, newType, target2, spreadArgType, spreadArg, spreadCount);
if (res != null)
return res;
res = SpreadGeneric.make(target2, spreadCount);
if (res != null)
res = convertArguments(token, res, newType, res.type(), null);
return res;
}
public static MethodHandle collectArguments(Access token,
MethodHandle target,
MethodType newType,
int collectArg,
MethodHandle collector) {
MethodType oldType = target.type(); // (a...,c)=>r
if (collector == null) {
int numCollect = newType.parameterCount() - oldType.parameterCount() + 1;
collector = ValueConversions.varargsArray(numCollect);
}
// newType // (a..., b...)=>r
MethodType colType = collector.type(); // (b...)=>c
// oldType // (a..., b...)=>r
assert(newType.parameterCount() == collectArg + colType.parameterCount());
assert(oldType.parameterCount() == collectArg + 1);
MethodHandle gtarget = convertArguments(token, target, oldType.generic(), oldType, null);
MethodHandle gcollector = convertArguments(token, collector, colType.generic(), colType, null);
if (gtarget == null || gcollector == null) return null;
MethodHandle gresult = FilterGeneric.makeArgumentCollector(gcollector, gtarget);
MethodHandle result = convertArguments(token, gresult, newType, gresult.type(), null);
return result;
}
public static MethodHandle filterArgument(Access token,
MethodHandle target,
int pos,
MethodHandle filter) {
Access.check(token);
MethodType ttype = target.type(), gttype = ttype.generic();
if (ttype != gttype) {
target = convertArguments(token, target, gttype, ttype, null);
ttype = gttype;
}
MethodType ftype = filter.type(), gftype = ftype.generic();
if (ftype.parameterCount() != 1)
throw new InternalError();
if (ftype != gftype) {
filter = convertArguments(token, filter, gftype, ftype, null);
ftype = gftype;
}
if (ftype == ttype) {
// simple unary case
return FilterOneArgument.make(filter, target);
}
return FilterGeneric.makeArgumentFilter(pos, filter, target);
}
public static MethodHandle foldArguments(Access token,
MethodHandle target,
MethodType newType,
MethodHandle combiner) {
Access.check(token);
MethodType oldType = target.type();
MethodType ctype = combiner.type();
MethodHandle gtarget = convertArguments(token, target, oldType.generic(), oldType, null);
MethodHandle gcombiner = convertArguments(token, combiner, ctype.generic(), ctype, null);
if (gtarget == null || gcombiner == null) return null;
MethodHandle gresult = FilterGeneric.makeArgumentFolder(gcombiner, gtarget);
MethodHandle result = convertArguments(token, gresult, newType, gresult.type(), null);
return result;
}
public static
MethodHandle dropArguments(Access token, MethodHandle target,
MethodType newType, int argnum) {
Access.check(token);
int drops = newType.parameterCount() - target.type().parameterCount();
MethodHandle res = AdapterMethodHandle.makeDropArguments(token, newType, target, argnum, drops);
if (res != null)
return res;
throw new UnsupportedOperationException("NYI");
}
private static class GuardWithTest extends BoundMethodHandle {
private final MethodHandle test, target, fallback;
private GuardWithTest(MethodHandle invoker,
MethodHandle test, MethodHandle target, MethodHandle fallback) {
super(Access.TOKEN, invoker);
this.test = test;
this.target = target;
this.fallback = fallback;
}
static MethodHandle make(Access token,
MethodHandle test, MethodHandle target, MethodHandle fallback) {
Access.check(token);
MethodType type = target.type();
int nargs = type.parameterCount();
if (nargs < INVOKES.length) {
MethodHandle invoke = INVOKES[nargs];
MethodType gtype = type.generic();
assert(invoke.type().dropParameterTypes(0,1) == gtype);
MethodHandle gtest = convertArguments(token, test, gtype.changeReturnType(boolean.class), test.type(), null);
MethodHandle gtarget = convertArguments(token, target, gtype, type, null);
MethodHandle gfallback = convertArguments(token, fallback, gtype, type, null);
if (gtest == null || gtarget == null || gfallback == null) return null;
MethodHandle gguard = new GuardWithTest(invoke, gtest, gtarget, gfallback);
return convertArguments(token, gguard, type, gtype, null);
} else {
MethodHandle invoke = VARARGS_INVOKE;
MethodType gtype = MethodType.genericMethodType(1);
assert(invoke.type().dropParameterTypes(0,1) == gtype);
MethodHandle gtest = spreadArguments(token, test, gtype.changeReturnType(boolean.class), 0);
MethodHandle gtarget = spreadArguments(token, target, gtype, 0);
MethodHandle gfallback = spreadArguments(token, fallback, gtype, 0);
MethodHandle gguard = new GuardWithTest(invoke, gtest, gtarget, gfallback);
if (gtest == null || gtarget == null || gfallback == null) return null;
return collectArguments(token, gguard, type, 0, null);
}
}
@Override
public String toString() {
return addTypeString(target, this);
}
private Object invoke_V(Object... av) throws Throwable {
if ((boolean) test.invokeExact(av))
return target.invokeExact(av);
return fallback.invokeExact(av);
}
private Object invoke_L0() throws Throwable {
if ((boolean) test.invokeExact())
return target.invokeExact();
return fallback.invokeExact();
}
private Object invoke_L1(Object a0) throws Throwable {
if ((boolean) test.invokeExact(a0))
return target.invokeExact(a0);
return fallback.invokeExact(a0);
}
private Object invoke_L2(Object a0, Object a1) throws Throwable {
if ((boolean) test.invokeExact(a0, a1))
return target.invokeExact(a0, a1);
return fallback.invokeExact(a0, a1);
}
private Object invoke_L3(Object a0, Object a1, Object a2) throws Throwable {
if ((boolean) test.invokeExact(a0, a1, a2))
return target.invokeExact(a0, a1, a2);
return fallback.invokeExact(a0, a1, a2);
}
private Object invoke_L4(Object a0, Object a1, Object a2, Object a3) throws Throwable {
if ((boolean) test.invokeExact(a0, a1, a2, a3))
return target.invokeExact(a0, a1, a2, a3);
return fallback.invokeExact(a0, a1, a2, a3);
}
private Object invoke_L5(Object a0, Object a1, Object a2, Object a3, Object a4) throws Throwable {
if ((boolean) test.invokeExact(a0, a1, a2, a3, a4))
return target.invokeExact(a0, a1, a2, a3, a4);
return fallback.invokeExact(a0, a1, a2, a3, a4);
}
private Object invoke_L6(Object a0, Object a1, Object a2, Object a3, Object a4, Object a5) throws Throwable {
if ((boolean) test.invokeExact(a0, a1, a2, a3, a4, a5))
return target.invokeExact(a0, a1, a2, a3, a4, a5);
return fallback.invokeExact(a0, a1, a2, a3, a4, a5);
}
private Object invoke_L7(Object a0, Object a1, Object a2, Object a3, Object a4, Object a5, Object a6) throws Throwable {
if ((boolean) test.invokeExact(a0, a1, a2, a3, a4, a5, a6))
return target.invokeExact(a0, a1, a2, a3, a4, a5, a6);
return fallback.invokeExact(a0, a1, a2, a3, a4, a5, a6);
}
private Object invoke_L8(Object a0, Object a1, Object a2, Object a3, Object a4, Object a5, Object a6, Object a7) throws Throwable {
if ((boolean) test.invokeExact(a0, a1, a2, a3, a4, a5, a6, a7))
return target.invokeExact(a0, a1, a2, a3, a4, a5, a6, a7);
return fallback.invokeExact(a0, a1, a2, a3, a4, a5, a6, a7);
}
static MethodHandle[] makeInvokes() {
ArrayList<MethodHandle> invokes = new ArrayList<MethodHandle>();
MethodHandles.Lookup lookup = IMPL_LOOKUP;
for (;;) {
int nargs = invokes.size();
String name = "invoke_L"+nargs;
MethodHandle invoke = null;
try {
invoke = lookup.findVirtual(GuardWithTest.class, name, MethodType.genericMethodType(nargs));
} catch (NoAccessException ex) {
}
if (invoke == null) break;
invokes.add(invoke);
}
assert(invokes.size() == 9); // current number of methods
return invokes.toArray(new MethodHandle[0]);
};
static final MethodHandle[] INVOKES = makeInvokes();
// For testing use this:
//static final MethodHandle[] INVOKES = Arrays.copyOf(makeInvokes(), 2);
static final MethodHandle VARARGS_INVOKE;
static {
try {
VARARGS_INVOKE = IMPL_LOOKUP.findVirtual(GuardWithTest.class, "invoke_V", MethodType.genericMethodType(0, true));
} catch (NoAccessException ex) {
throw uncaughtException(ex);
}
}
}
public static
MethodHandle makeGuardWithTest(Access token,
MethodHandle test,
MethodHandle target,
MethodHandle fallback) {
return GuardWithTest.make(token, test, target, fallback);
}
private static class GuardWithCatch extends BoundMethodHandle {
private final MethodHandle target;
private final Class<? extends Throwable> exType;
private final MethodHandle catcher;
public GuardWithCatch(MethodHandle target, Class<? extends Throwable> exType, MethodHandle catcher) {
this(INVOKES[target.type().parameterCount()], target, exType, catcher);
}
public GuardWithCatch(MethodHandle invoker,
MethodHandle target, Class<? extends Throwable> exType, MethodHandle catcher) {
super(Access.TOKEN, invoker);
this.target = target;
this.exType = exType;
this.catcher = catcher;
}
@Override
public String toString() {
return addTypeString(target, this);
}
private Object invoke_V(Object... av) throws Throwable {
try {
return target.invokeExact(av);
} catch (Throwable t) {
if (!exType.isInstance(t)) throw t;
return catcher.invokeExact(t, av);
}
}
private Object invoke_L0() throws Throwable {
try {
return target.invokeExact();
} catch (Throwable t) {
if (!exType.isInstance(t)) throw t;
return catcher.invokeExact(t);
}
}
private Object invoke_L1(Object a0) throws Throwable {
try {
return target.invokeExact(a0);
} catch (Throwable t) {
if (!exType.isInstance(t)) throw t;
return catcher.invokeExact(t, a0);
}
}
private Object invoke_L2(Object a0, Object a1) throws Throwable {
try {
return target.invokeExact(a0, a1);
} catch (Throwable t) {
if (!exType.isInstance(t)) throw t;
return catcher.invokeExact(t, a0, a1);
}
}
private Object invoke_L3(Object a0, Object a1, Object a2) throws Throwable {
try {
return target.invokeExact(a0, a1, a2);
} catch (Throwable t) {
if (!exType.isInstance(t)) throw t;
return catcher.invokeExact(t, a0, a1, a2);
}
}
private Object invoke_L4(Object a0, Object a1, Object a2, Object a3) throws Throwable {
try {
return target.invokeExact(a0, a1, a2, a3);
} catch (Throwable t) {
if (!exType.isInstance(t)) throw t;
return catcher.invokeExact(t, a0, a1, a2, a3);
}
}
private Object invoke_L5(Object a0, Object a1, Object a2, Object a3, Object a4) throws Throwable {
try {
return target.invokeExact(a0, a1, a2, a3, a4);
} catch (Throwable t) {
if (!exType.isInstance(t)) throw t;
return catcher.invokeExact(t, a0, a1, a2, a3, a4);
}
}
private Object invoke_L6(Object a0, Object a1, Object a2, Object a3, Object a4, Object a5) throws Throwable {
try {
return target.invokeExact(a0, a1, a2, a3, a4, a5);
} catch (Throwable t) {
if (!exType.isInstance(t)) throw t;
return catcher.invokeExact(t, a0, a1, a2, a3, a4, a5);
}
}
private Object invoke_L7(Object a0, Object a1, Object a2, Object a3, Object a4, Object a5, Object a6) throws Throwable {
try {
return target.invokeExact(a0, a1, a2, a3, a4, a5, a6);
} catch (Throwable t) {
if (!exType.isInstance(t)) throw t;
return catcher.invokeExact(t, a0, a1, a2, a3, a4, a5, a6);
}
}
private Object invoke_L8(Object a0, Object a1, Object a2, Object a3, Object a4, Object a5, Object a6, Object a7) throws Throwable {
try {
return target.invokeExact(a0, a1, a2, a3, a4, a5, a6, a7);
} catch (Throwable t) {
if (!exType.isInstance(t)) throw t;
return catcher.invokeExact(t, a0, a1, a2, a3, a4, a5, a6, a7);
}
}
static MethodHandle[] makeInvokes() {
ArrayList<MethodHandle> invokes = new ArrayList<MethodHandle>();
MethodHandles.Lookup lookup = IMPL_LOOKUP;
for (;;) {
int nargs = invokes.size();
String name = "invoke_L"+nargs;
MethodHandle invoke = null;
try {
invoke = lookup.findVirtual(GuardWithCatch.class, name, MethodType.genericMethodType(nargs));
} catch (NoAccessException ex) {
}
if (invoke == null) break;
invokes.add(invoke);
}
assert(invokes.size() == 9); // current number of methods
return invokes.toArray(new MethodHandle[0]);
};
static final MethodHandle[] INVOKES = makeInvokes();
// For testing use this:
//static final MethodHandle[] INVOKES = Arrays.copyOf(makeInvokes(), 2);
static final MethodHandle VARARGS_INVOKE;
static {
try {
VARARGS_INVOKE = IMPL_LOOKUP.findVirtual(GuardWithCatch.class, "invoke_V", MethodType.genericMethodType(0, true));
} catch (NoAccessException ex) {
throw uncaughtException(ex);
}
}
}
public static
MethodHandle makeGuardWithCatch(Access token,
MethodHandle target,
Class<? extends Throwable> exType,
MethodHandle catcher) {
Access.check(token);
MethodType type = target.type();
MethodType ctype = catcher.type();
int nargs = type.parameterCount();
if (nargs < GuardWithCatch.INVOKES.length) {
MethodType gtype = type.generic();
MethodType gcatchType = gtype.insertParameterTypes(0, Throwable.class);
MethodHandle gtarget = convertArguments(token, target, gtype, type, null);
MethodHandle gcatcher = convertArguments(token, catcher, gcatchType, ctype, null);
MethodHandle gguard = new GuardWithCatch(gtarget, exType, gcatcher);
if (gtarget == null || gcatcher == null || gguard == null) return null;
return convertArguments(token, gguard, type, gtype, null);
} else {
MethodType gtype = MethodType.genericMethodType(0, true);
MethodType gcatchType = gtype.insertParameterTypes(0, Throwable.class);
MethodHandle gtarget = spreadArguments(token, target, gtype, 0);
MethodHandle gcatcher = spreadArguments(token, catcher, gcatchType, 1);
MethodHandle gguard = new GuardWithCatch(GuardWithCatch.VARARGS_INVOKE, gtarget, exType, gcatcher);
if (gtarget == null || gcatcher == null || gguard == null) return null;
return collectArguments(token, gguard, type, 0, null);
}
}
public static
MethodHandle throwException(Access token, MethodType type) {
Access.check(token);
return AdapterMethodHandle.makeRetypeRaw(token, type, THROW_EXCEPTION);
}
static final MethodHandle THROW_EXCEPTION;
static {
try {
THROW_EXCEPTION
= IMPL_LOOKUP.findStatic(MethodHandleImpl.class, "throwException",
MethodType.methodType(Empty.class, Throwable.class));
} catch (NoAccessException ex) {
throw new RuntimeException(ex);
}
}
static <T extends Throwable> Empty throwException(T t) throws T { throw t; }
public static String getNameString(Access token, MethodHandle target) {
Access.check(token);
MemberName name = null;
if (target != null)
name = MethodHandleNatives.getMethodName(target);
if (name == null)
return "invoke" + target.type();
return name.getName() + target.type();
}
static String addTypeString(Object obj, MethodHandle target) {
String str = String.valueOf(obj);
if (target == null) return str;
int paren = str.indexOf('(');
if (paren >= 0) str = str.substring(0, paren);
return str + target.type();
}
static void checkSpreadArgument(Object av, int n) {
if (av == null ? n != 0 : ((Object[])av).length != n)
throw newIllegalArgumentException("Array is not of length "+n);
}
static void raiseException(int code, Object actual, Object required) {
String message;
// disregard the identity of the actual object, if it is not a class:
if (!(actual instanceof Class) && !(actual instanceof MethodType))
actual = actual.getClass();
if (actual != null)
message = "required "+required+" but encountered "+actual;
else
message = "required "+required;
switch (code) {
case 192: // checkcast
throw new ClassCastException(message);
default:
throw new InternalError("unexpected code "+code+": "+message);
}
}
// Linkage support:
public static void registerBootstrap(Access token, Class<?> callerClass, MethodHandle bootstrapMethod) {
Access.check(token);
MethodHandleNatives.registerBootstrap(callerClass, bootstrapMethod);
}
public static MethodHandle getBootstrap(Access token, Class<?> callerClass) {
Access.check(token);
return MethodHandleNatives.getBootstrap(callerClass);
}
public static MethodHandle asVarargsCollector(Access token, MethodHandle target, Class<?> arrayType) {
Access.check(token);
return AdapterMethodHandle.makeVarargsCollector(token, target, arrayType);
}
}