corda/classpath/java/lang/reflect/Proxy.java
Joel Dice 2465459079 implement basic Java 8 lambda support
The two big pieces here are basic invokedynamic support and a working
version of LambdaMetaFactory.metafactory.  The latter works by
dynamically building a synthetic class with three methods: a static
factory method, a constructor for the factory method to call, and a
method to satisfy the requested interface which defers to the
specified MethodHandle.

This work relies heavily on Avian's specific MethodType and
MethodHandle implementations, which provide extra, non-standard
features to make code generation easier.  That means we'll probably
need to use Avian's versions of java.lang.invoke.* even when building
with the OpenJDK or Android class libraries.
2015-08-06 13:30:18 -06:00

431 lines
12 KiB
Java

/* Copyright (c) 2008-2015, Avian Contributors
Permission to use, copy, modify, and/or distribute this software
for any purpose with or without fee is hereby granted, provided
that the above copyright notice and this permission notice appear
in all copies.
There is NO WARRANTY for this software. See license.txt for
details. */
package java.lang.reflect;
import static avian.Stream.write1;
import static avian.Stream.write2;
import static avian.Stream.write4;
import static avian.Stream.set4;
import static avian.Assembler.*;
import avian.SystemClassLoader;
import avian.Classes;
import avian.ConstantPool;
import avian.ConstantPool.PoolEntry;
import avian.Assembler;
import avian.Assembler.FieldData;
import avian.Assembler.MethodData;
import java.util.List;
import java.util.ArrayList;
import java.util.Map;
import java.util.HashMap;
import java.util.Set;
import java.util.HashSet;
import java.io.OutputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
public class Proxy {
private static int nextNumber;
protected InvocationHandler h;
protected final static Map<Class, Method[]> methodRefsMap =
new HashMap<Class, Method[]>();
protected final Method[] methodRefs;
public Proxy() {
methodRefs = methodRefsMap.get(getClass());
}
public static Class getProxyClass(ClassLoader loader,
Class ... interfaces)
{
for (Class c: interfaces) {
if (! c.isInterface()) {
throw new IllegalArgumentException();
}
}
int number;
synchronized (Proxy.class) {
number = nextNumber++;
}
try {
return makeClass(loader, interfaces, "Proxy-" + number);
} catch (IOException e) {
AssertionError error = new AssertionError();
error.initCause(e);
throw error;
}
}
public static boolean isProxyClass(Class c) {
return c.getName().startsWith("Proxy-");
}
public static InvocationHandler getInvocationHandler(Object proxy) {
return ((Proxy) proxy).h;
}
private static byte[] makeInvokeCode(List<PoolEntry> pool,
String className,
byte[] spec,
int parameterCount,
int parameterFootprint,
int index)
throws IOException
{
ByteArrayOutputStream out = new ByteArrayOutputStream();
write2(out, 8); // max stack
write2(out, parameterFootprint); // max locals
write4(out, 0); // length (we'll set the real value later)
write1(out, aload_0);
write1(out, getfield);
write2(out, ConstantPool.addFieldRef
(pool, "java/lang/reflect/Proxy",
"h", "Ljava/lang/reflect/InvocationHandler;") + 1);
write1(out, aload_0);
write1(out, aload_0);
write1(out, getfield);
write2(out, ConstantPool.addFieldRef
(pool, className,
"methodRefs", "[Ljava/lang/reflect/Method;") + 1);
write1(out, ldc_w);
write2(out, ConstantPool.addInteger(pool, index) + 1);
write1(out, aaload);
write1(out, ldc_w);
write2(out, ConstantPool.addInteger(pool, parameterCount) + 1);
write1(out, anewarray);
write2(out, ConstantPool.addClass(pool, "java/lang/Object") + 1);
int ai = 0;
int si;
for (si = 1; spec[si] != ')'; ++si) {
write1(out, dup);
write1(out, ldc_w);
write2(out, ConstantPool.addInteger(pool, ai) + 1);
switch (spec[si]) {
case 'L':
++ si;
while (spec[si] != ';') ++si;
write1(out, aload);
write1(out, ai + 1);
break;
case '[':
++ si;
while (spec[si] == '[') ++si;
switch (spec[si]) {
case 'L':
++ si;
while (spec[si] != ';') ++si;
break;
default:
break;
}
write1(out, aload);
write1(out, ai + 1);
break;
case 'Z':
write1(out, iload);
write1(out, ai + 1);
write1(out, invokestatic);
write2(out, ConstantPool.addMethodRef
(pool, "java/lang/Boolean",
"valueOf", "(Z)Ljava/lang/Boolean;") + 1);
break;
case 'B':
write1(out, iload);
write1(out, ai + 1);
write1(out, invokestatic);
write2(out, ConstantPool.addMethodRef
(pool, "java/lang/Byte",
"valueOf", "(B)Ljava/lang/Byte;") + 1);
break;
case 'S':
write1(out, iload);
write1(out, ai + 1);
write1(out, invokestatic);
write2(out, ConstantPool.addMethodRef
(pool, "java/lang/Short",
"valueOf", "(S)Ljava/lang/Short;") + 1);
break;
case 'C':
write1(out, iload);
write1(out, ai + 1);
write1(out, invokestatic);
write2(out, ConstantPool.addMethodRef
(pool, "java/lang/Character",
"valueOf", "(C)Ljava/lang/Character;") + 1);
break;
case 'I':
write1(out, iload);
write1(out, ai + 1);
write1(out, invokestatic);
write2(out, ConstantPool.addMethodRef
(pool, "java/lang/Integer",
"valueOf", "(I)Ljava/lang/Integer;") + 1);
break;
case 'F':
write1(out, fload);
write1(out, ai + 1);
write1(out, invokestatic);
write2(out, ConstantPool.addMethodRef
(pool, "java/lang/Float",
"valueOf", "(F)Ljava/lang/Float;") + 1);
break;
case 'J':
write1(out, lload);
write1(out, ai + 1);
write1(out, invokestatic);
write2(out, ConstantPool.addMethodRef
(pool, "java/lang/Long",
"valueOf", "(J)Ljava/lang/Long;") + 1);
++ ai;
break;
case 'D':
write1(out, dload);
write1(out, ai + 1);
write1(out, invokestatic);
write2(out, ConstantPool.addMethodRef
(pool, "java/lang/Double",
"valueOf", "(D)Ljava/lang/Double;") + 1);
++ ai;
break;
default: throw new IllegalArgumentException();
}
write1(out, aastore);
++ ai;
}
write1(out, invokeinterface);
write2(out, ConstantPool.addMethodRef
(pool, "java/lang/reflect/InvocationHandler",
"invoke",
"(Ljava/lang/Object;"
+ "Ljava/lang/reflect/Method;"
+ "[Ljava/lang/Object;)"
+ "Ljava/lang/Object;") + 1);
write2(out, 0); // this will be ignored by the VM
switch (spec[si + 1]) {
case 'L':
case '[':
write1(out, areturn);
break;
case 'Z':
write1(out, invokevirtual);
write2(out, ConstantPool.addMethodRef
(pool, "java/lang/Boolean", "booleanValue", "()Z") + 1);
write1(out, ireturn);
break;
case 'B':
write1(out, invokevirtual);
write2(out, ConstantPool.addMethodRef
(pool, "java/lang/Byte", "byteValue", "()B") + 1);
write1(out, ireturn);
break;
case 'C':
write1(out, invokevirtual);
write2(out, ConstantPool.addMethodRef
(pool, "java/lang/Character", "charValue", "()C") + 1);
write1(out, ireturn);
break;
case 'S':
write1(out, invokevirtual);
write2(out, ConstantPool.addMethodRef
(pool, "java/lang/Short", "shortValue", "()S") + 1);
write1(out, ireturn);
break;
case 'I':
write1(out, invokevirtual);
write2(out, ConstantPool.addMethodRef
(pool, "java/lang/Integer", "intValue", "()I") + 1);
write1(out, ireturn);
break;
case 'F':
write1(out, invokevirtual);
write2(out, ConstantPool.addMethodRef
(pool, "java/lang/Float", "floatValue", "()F") + 1);
write1(out, freturn);
break;
case 'J':
write1(out, invokevirtual);
write2(out, ConstantPool.addMethodRef
(pool, "java/lang/Long", "longValue", "()J") + 1);
write1(out, lreturn);
break;
case 'D':
write1(out, invokevirtual);
write2(out, ConstantPool.addMethodRef
(pool, "java/lang/Double", "doubleValue", "()D") + 1);
write1(out, dreturn);
break;
case 'V':
write1(out, pop);
write1(out, return_);
break;
default: throw new IllegalArgumentException();
}
write2(out, 0); // exception handler table length
write2(out, 0); // attribute count
byte[] result = out.toByteArray();
set4(result, 4, result.length - 12);
return result;
}
private static byte[] makeConstructorCode(List<PoolEntry> pool)
throws IOException
{
ByteArrayOutputStream out = new ByteArrayOutputStream();
write2(out, 2); // max stack
write2(out, 2); // max locals
write4(out, 10); // length
write1(out, aload_0);
write1(out, invokespecial);
write2(out, ConstantPool.addMethodRef
(pool, "java/lang/reflect/Proxy",
"<init>", "()V") + 1);
write1(out, aload_0);
write1(out, aload_1);
write1(out, putfield);
write2(out, ConstantPool.addFieldRef
(pool, "java/lang/reflect/Proxy",
"h", "Ljava/lang/reflect/InvocationHandler;") + 1);
write1(out, return_);
write2(out, 0); // exception handler table length
write2(out, 0); // attribute count
return out.toByteArray();
}
private static Class makeClass(ClassLoader loader,
Class[] interfaces,
String name)
throws IOException
{
List<PoolEntry> pool = new ArrayList();
int[] interfaceIndexes = new int[interfaces.length];
for (int i = 0; i < interfaces.length; ++i) {
interfaceIndexes[i] = ConstantPool.addClass
(pool, interfaces[i].getName().replace('.', '/'));
}
Set<String> specs = new HashSet<String>();
List<MethodData> methodTable = new ArrayList<MethodData>();
List<Method> refs = new ArrayList<Method>();
for (Class c: interfaces) {
avian.VMMethod[] ivtable = SystemClassLoader.vmClass(c).virtualTable;
if (ivtable != null) {
for (avian.VMMethod m: ivtable) {
String spec = Classes.toString(m.name) + Classes.toString(m.spec);
if (specs.contains(spec)) {
continue;
}
methodTable.add(new MethodData
(Modifier.PUBLIC,
ConstantPool.addUtf8(pool, Classes.toString(m.name)),
ConstantPool.addUtf8(pool, Classes.toString(m.spec)),
makeInvokeCode(pool, name, m.spec, m.parameterCount,
m.parameterFootprint, methodTable.size())));
refs.add(Classes.makeMethod(m));
}
}
}
methodTable.add(new MethodData
(Modifier.PUBLIC,
ConstantPool.addUtf8(pool, "<init>"),
ConstantPool.addUtf8
(pool, "(Ljava/lang/reflect/InvocationHandler;)V"),
makeConstructorCode(pool)));
int nameIndex = ConstantPool.addClass(pool, name);
int superIndex = ConstantPool.addClass(pool, "java/lang/reflect/Proxy");
ByteArrayOutputStream out = new ByteArrayOutputStream();
Assembler.writeClass
(out, pool, nameIndex, superIndex, interfaceIndexes,
new FieldData[0],
methodTable.toArray(new MethodData[methodTable.size()]));
byte[] classData = out.toByteArray();
Class result = avian.SystemClassLoader.getClass
(avian.Classes.defineVMClass(loader, classData, 0, classData.length));
methodRefsMap.put(result, refs.toArray(new Method[refs.size()]));
return result;
}
public static Object newProxyInstance(ClassLoader loader,
Class[] interfaces,
InvocationHandler handler)
{
try {
return Proxy.getProxyClass(loader, interfaces)
.getConstructor(new Class[] { InvocationHandler.class })
.newInstance(new Object[] { handler });
} catch (Exception e) {
AssertionError error = new AssertionError();
error.initCause(e);
throw error;
}
}
}