2 * Copyright (c) 2019 PANTHEON.tech, s.r.o. and others. All rights reserved.
4 * This program and the accompanying materials are made available under the
5 * terms of the Eclipse Public License v1.0 which accompanies this distribution,
6 * and is available at http://www.eclipse.org/legal/epl-v10.html
8 package org.opendaylight.mdsal.binding.dom.codec.impl;
10 import static com.google.common.base.Verify.verify;
11 import static com.google.common.base.Verify.verifyNotNull;
12 import static java.util.Objects.requireNonNull;
13 import static org.opendaylight.mdsal.binding.dom.codec.impl.ByteBuddyUtils.THIS;
14 import static org.opendaylight.mdsal.binding.dom.codec.impl.ByteBuddyUtils.getField;
15 import static org.opendaylight.mdsal.binding.dom.codec.impl.ByteBuddyUtils.invokeMethod;
16 import static org.opendaylight.mdsal.binding.dom.codec.impl.ByteBuddyUtils.putField;
18 import com.google.common.collect.ImmutableMap;
19 import com.google.common.collect.Maps;
20 import java.lang.invoke.MethodHandles;
21 import java.lang.invoke.MethodHandles.Lookup;
22 import java.lang.invoke.VarHandle;
23 import java.lang.reflect.Method;
24 import java.util.ArrayList;
25 import java.util.Arrays;
26 import java.util.Comparator;
27 import java.util.List;
29 import java.util.Map.Entry;
30 import java.util.Objects;
31 import java.util.Optional;
32 import net.bytebuddy.ByteBuddy;
33 import net.bytebuddy.description.field.FieldDescription;
34 import net.bytebuddy.description.type.TypeDefinition;
35 import net.bytebuddy.description.type.TypeDescription;
36 import net.bytebuddy.description.type.TypeDescription.ForLoadedType;
37 import net.bytebuddy.description.type.TypeDescription.Generic;
38 import net.bytebuddy.dynamic.DynamicType.Builder;
39 import net.bytebuddy.dynamic.scaffold.InstrumentedType;
40 import net.bytebuddy.implementation.Implementation;
41 import net.bytebuddy.implementation.bytecode.ByteCodeAppender;
42 import net.bytebuddy.implementation.bytecode.StackManipulation;
43 import net.bytebuddy.implementation.bytecode.assign.TypeCasting;
44 import net.bytebuddy.implementation.bytecode.constant.ClassConstant;
45 import net.bytebuddy.implementation.bytecode.constant.IntegerConstant;
46 import net.bytebuddy.implementation.bytecode.constant.TextConstant;
47 import net.bytebuddy.implementation.bytecode.member.MethodReturn;
48 import net.bytebuddy.implementation.bytecode.member.MethodVariableAccess;
49 import net.bytebuddy.jar.asm.Label;
50 import net.bytebuddy.jar.asm.Opcodes;
51 import org.eclipse.jdt.annotation.Nullable;
52 import org.opendaylight.mdsal.binding.dom.codec.impl.ClassGeneratorBridge.LocalNameProvider;
53 import org.opendaylight.mdsal.binding.dom.codec.impl.ClassGeneratorBridge.NodeContextSupplierProvider;
54 import org.opendaylight.mdsal.binding.dom.codec.loader.CodecClassLoader;
55 import org.opendaylight.mdsal.binding.dom.codec.loader.CodecClassLoader.ClassGenerator;
56 import org.opendaylight.mdsal.binding.dom.codec.loader.CodecClassLoader.GeneratorResult;
57 import org.opendaylight.mdsal.binding.spec.naming.BindingMapping;
58 import org.opendaylight.yangtools.yang.binding.DataObject;
59 import org.slf4j.Logger;
60 import org.slf4j.LoggerFactory;
63 * Private support for generating {@link CodecDataObject} and {@link AugmentableCodecDataObject} specializations.
66 * Code generation here is probably more involved than usual mainly due to the fact we *really* want to express the
67 * strong connection between a generated class to the extent possible. In most cases (grouping-generated types) this
68 * involves one level of indirection, which is a safe approach. If we are dealing with a type generated outside of a
69 * grouping statement, though, we are guaranteed instantiation-invariance and hence can hard-wire to a runtime-constant
70 * {@link NodeContextSupplier} -- which provides significant boost to JITs ability to optimize code -- especially with
71 * inlining and constant propagation.
74 * The accessor mapping performance is critical due to users typically not taking care of storing the results acquired
75 * by an invocation, assuming the accessors are backed by a normal field -- which of course is not true, as the results
76 * are lazily computed.
79 * The design is such that for a particular structure like:
87 * we end up generating a class with the following layout:
89 * public final class Foo$$$codecImpl extends CodecDataObject implements Foo {
90 * private static final VarHandle getBar$$$V;
91 * private volatile Object getBar;
93 * public Foo$$$codecImpl(NormalizedNodeContainer data) {
97 * public Bar getBar() {
98 * return (Bar) codecMember(getBar$$$V, "bar");
104 * This strategy minimizes the bytecode footprint and follows the generally good idea of keeping common logic in a
105 * single place in a maintainable form. The glue code is extremely light (~6 instructions), which is beneficial on both
106 * sides of invocation:
108 * <li>generated method can readily be inlined into the caller</li>
109 * <li>it forms a call site into which codeMember() can be inlined with VarHandle being constant</li>
113 * The second point is important here, as it allows the invocation logic around VarHandle to completely disappear,
114 * becoming synonymous with operations on a field. Even though the field itself is declared as volatile, it is only ever
115 * accessed through helper method using VarHandles -- and those helpers are using relaxed field ordering
116 * of {@code getAcquire()}/{@code setRelease()} memory semantics.
119 * Furthermore there are distinct {@code codecMember} methods, each of which supports a different invocation style:
121 * <li>with {@code String}, which ends up looking up a {@link ValueNodeCodecContext}</li>
122 * <li>with {@code Class}, which ends up looking up a {@link DataContainerCodecContext}</li>
123 * <li>with {@code NodeContextSupplier}, which performs a direct load</li>
125 * The third mode of operation requires that the object being implemented is not defined in a {@code grouping}, because
126 * it welds the object to a particular namespace -- hence it trades namespace mobility for access speed.
129 * The sticky point here is the NodeContextSupplier, as it is a heap object which cannot normally be looked up from the
130 * static context in which the static class initializer operates -- so we need perform some sort of a trick here.
131 * Even though ByteBuddy provides facilities for bridging references to type fields, those facilities operate on
132 * volatile fields -- hence they do not quite work for us.
135 * Another alternative, which we used in Javassist-generated DataObjectSerializers, is to muck with the static field
136 * using reflection -- which works, but requires redefinition of Field.modifiers, which is something Java 9+ complains
137 * about quite noisily.
140 * We take a different approach here, which takes advantage of the fact we are in control of both code generation (here)
141 * and class loading (in {@link CodecClassLoader}). The process is performed in four steps:
143 * <li>During code generation, the context fields are pointed towards
144 * {@link ClassGeneratorBridge#resolveNodeContextSupplier(String)} and
145 * {@link ClassGeneratorBridge#resolveKey(String)} methods, which are public and static, hence perfectly usable
146 * in the context of a class initializer.</li>
147 * <li>During class loading of generated byte code, the original instance of the generator is called to wrap the actual
148 * class loading operation. At this point the generator installs itself as the current generator for this thread via
149 * {@link ClassGeneratorBridge#setup(CodecDataObjectGenerator)} and allows the class to be loaded.
150 * <li>After the class has been loaded, but before the call returns, we will force the class to initialize, at which
151 * point the static invocations will be redirected to {@link #resolveNodeContextSupplier(String)} and
152 * {@link #resolveKey(String)} methods, thus initializing the fields to the intended constants.</li>
153 * <li>Before returning from the class loading call, the generator will detach itself via
154 * {@link ClassGeneratorBridge#tearDown(CodecDataObjectGenerator)}.</li>
158 * This strategy works due to close cooperation with the target ClassLoader, as the entire code generation and loading
159 * block runs with the class loading lock for this FQCN and the reference is not leaked until the process completes.
161 abstract class CodecDataObjectGenerator<T extends CodecDataObject<?>> implements ClassGenerator<T> {
162 // Not reusable definition: we can inline NodeContextSuppliers without a problem
163 // FIXME: 6.0.0: wire this implementation, which requires that BindingRuntimeTypes provides information about types
164 // being generated from within a grouping
165 private static final class Fixed<T extends CodecDataObject<?>> extends CodecDataObjectGenerator<T>
166 implements NodeContextSupplierProvider<T> {
167 private final ImmutableMap<Method, NodeContextSupplier> properties;
169 Fixed(final TypeDescription superClass, final ImmutableMap<Method, NodeContextSupplier> properties,
170 final @Nullable Method keyMethod) {
171 super(superClass, keyMethod);
172 this.properties = requireNonNull(properties);
176 Builder<T> generateGetters(final Builder<T> builder) {
177 Builder<T> tmp = builder;
178 for (Method method : properties.keySet()) {
179 LOG.trace("Generating for fixed method {}", method);
180 final String methodName = method.getName();
181 final TypeDescription retType = TypeDescription.ForLoadedType.of(method.getReturnType());
182 tmp = tmp.defineMethod(methodName, retType, PUB_FINAL).intercept(
183 new SupplierGetterMethodImplementation(methodName, retType));
189 ArrayList<Method> getterMethods() {
190 return new ArrayList<>(properties.keySet());
194 public NodeContextSupplier resolveNodeContextSupplier(final String methodName) {
195 final Optional<Entry<Method, NodeContextSupplier>> found = properties.entrySet().stream()
196 .filter(entry -> methodName.equals(entry.getKey().getName())).findAny();
197 verify(found.isPresent(), "Failed to find property for %s in %s", methodName, this);
198 return verifyNotNull(found.get().getValue());
202 // Reusable definition: we have to rely on context lookups
203 private static final class Reusable<T extends CodecDataObject<?>> extends CodecDataObjectGenerator<T>
204 implements LocalNameProvider<T> {
205 private final ImmutableMap<Method, ValueNodeCodecContext> simpleProperties;
206 private final Map<Method, Class<?>> daoProperties;
208 Reusable(final TypeDescription superClass, final ImmutableMap<Method, ValueNodeCodecContext> simpleProperties,
209 final Map<Method, Class<?>> daoProperties, final @Nullable Method keyMethod) {
210 super(superClass, keyMethod);
211 this.simpleProperties = requireNonNull(simpleProperties);
212 this.daoProperties = requireNonNull(daoProperties);
216 Builder<T> generateGetters(final Builder<T> builder) {
217 Builder<T> tmp = builder;
218 for (Method method : simpleProperties.keySet()) {
219 LOG.trace("Generating for simple method {}", method);
220 final String methodName = method.getName();
221 final TypeDescription retType = TypeDescription.ForLoadedType.of(method.getReturnType());
222 tmp = tmp.defineMethod(methodName, retType, PUB_FINAL).intercept(
223 new SimpleGetterMethodImplementation(methodName, retType));
225 for (Entry<Method, Class<?>> entry : daoProperties.entrySet()) {
226 final Method method = entry.getKey();
227 LOG.trace("Generating for structured method {}", method);
228 final String methodName = method.getName();
229 final TypeDescription retType = TypeDescription.ForLoadedType.of(method.getReturnType());
230 tmp = tmp.defineMethod(methodName, retType, PUB_FINAL).intercept(
231 new StructuredGetterMethodImplementation(methodName, retType, entry.getValue()));
238 ArrayList<Method> getterMethods() {
239 final ArrayList<Method> ret = new ArrayList<>(simpleProperties.size() + daoProperties.size());
240 ret.addAll(simpleProperties.keySet());
241 ret.addAll(daoProperties.keySet());
246 public String resolveLocalName(final String methodName) {
247 final Optional<Entry<Method, ValueNodeCodecContext>> found = simpleProperties.entrySet().stream()
248 .filter(entry -> methodName.equals(entry.getKey().getName())).findAny();
249 verify(found.isPresent(), "Failed to find property for %s in %s", methodName, this);
250 return found.get().getValue().getSchema().getQName().getLocalName();
254 private static final Logger LOG = LoggerFactory.getLogger(CodecDataObjectGenerator.class);
255 private static final Generic BB_BOOLEAN = TypeDefinition.Sort.describe(boolean.class);
256 private static final Generic BB_DATAOBJECT = TypeDefinition.Sort.describe(DataObject.class);
257 private static final Generic BB_INT = TypeDefinition.Sort.describe(int.class);
258 private static final Generic BB_STRING = TypeDefinition.Sort.describe(String.class);
259 private static final TypeDescription BB_CDO = ForLoadedType.of(CodecDataObject.class);
260 private static final TypeDescription BB_ACDO = ForLoadedType.of(AugmentableCodecDataObject.class);
261 private static final Comparator<Method> METHOD_BY_ALPHABET = Comparator.comparing(Method::getName);
263 private static final StackManipulation ARRAYS_EQUALS = invokeMethod(Arrays.class, "equals",
264 byte[].class, byte[].class);
265 private static final StackManipulation OBJECTS_EQUALS = invokeMethod(Objects.class, "equals",
266 Object.class, Object.class);
267 private static final StackManipulation FIRST_ARG_REF = MethodVariableAccess.REFERENCE.loadFrom(1);
269 private static final int PROT_FINAL = Opcodes.ACC_PROTECTED | Opcodes.ACC_FINAL | Opcodes.ACC_SYNTHETIC;
270 private static final int PUB_FINAL = Opcodes.ACC_PUBLIC | Opcodes.ACC_FINAL | Opcodes.ACC_SYNTHETIC;
272 private static final ByteBuddy BB = new ByteBuddy();
274 private final TypeDescription superClass;
275 private final Method keyMethod;
277 CodecDataObjectGenerator(final TypeDescription superClass, final @Nullable Method keyMethod) {
278 this.superClass = requireNonNull(superClass);
279 this.keyMethod = keyMethod;
282 static <D extends DataObject, T extends CodecDataObject<T>> Class<T> generate(final CodecClassLoader loader,
283 final Class<D> bindingInterface, final ImmutableMap<Method, ValueNodeCodecContext> simpleProperties,
284 final Map<Method, Class<?>> daoProperties, final Method keyMethod) {
285 return loader.generateClass(bindingInterface, "codecImpl",
286 new Reusable<>(BB_CDO, simpleProperties, daoProperties, keyMethod));
289 static <D extends DataObject, T extends CodecDataObject<T>> Class<T> generateAugmentable(
290 final CodecClassLoader loader, final Class<D> bindingInterface,
291 final ImmutableMap<Method, ValueNodeCodecContext> simpleProperties,
292 final Map<Method, Class<?>> daoProperties, final Method keyMethod) {
293 return loader.generateClass(bindingInterface, "codecImpl",
294 new Reusable<>(BB_ACDO, simpleProperties, daoProperties, keyMethod));
298 public final GeneratorResult<T> generateClass(final CodecClassLoader loeader, final String fqcn,
299 final Class<?> bindingInterface) {
300 LOG.trace("Generating class {}", fqcn);
302 final Generic bindingDef = TypeDefinition.Sort.describe(bindingInterface);
303 @SuppressWarnings("unchecked")
304 Builder<T> builder = (Builder<T>) BB.subclass(Generic.Builder.parameterizedType(superClass, bindingDef).build())
305 .visit(ByteBuddyUtils.computeFrames()).name(fqcn).implement(bindingDef);
307 builder = generateGetters(builder);
309 if (keyMethod != null) {
310 LOG.trace("Generating for key {}", keyMethod);
311 final String methodName = keyMethod.getName();
312 final TypeDescription retType = TypeDescription.ForLoadedType.of(keyMethod.getReturnType());
313 builder = builder.defineMethod(methodName, retType, PUB_FINAL).intercept(
314 new KeyMethodImplementation(methodName, retType));
317 // Index all property methods, turning them into "getFoo()" invocations, retaining order. We will be using
318 // those invocations in each of the three methods. Note that we do not glue the invocations to 'this', as we
319 // will be invoking them on 'other' in codecEquals()
320 final ArrayList<Method> properties = getterMethods();
321 // Make sure properties are alpha-sorted
322 properties.sort(METHOD_BY_ALPHABET);
323 final ImmutableMap<StackManipulation, Method> methods = Maps.uniqueIndex(properties,
324 ByteBuddyUtils::invokeMethod);
327 return GeneratorResult.of(builder
328 // codecHashCode() ...
329 .defineMethod("codecHashCode", BB_INT, PROT_FINAL)
330 .intercept(codecHashCode(bindingInterface))
331 // ... codecEquals() ...
332 .defineMethod("codecEquals", BB_BOOLEAN, PROT_FINAL).withParameter(BB_DATAOBJECT)
333 .intercept(codecEquals(methods))
334 // ... toString() ...
335 .defineMethod("toString", BB_STRING, PUB_FINAL)
336 .intercept(toString(bindingInterface))
341 abstract Builder<T> generateGetters(Builder<T> builder);
343 abstract ArrayList<Method> getterMethods();
345 private static Implementation codecEquals(final ImmutableMap<StackManipulation, Method> properties) {
346 // Label for 'return false;'
347 final Label falseLabel = new Label();
348 // Condition for 'if (!...)'
349 final StackManipulation ifFalse = ByteBuddyUtils.ifEq(falseLabel);
351 final List<StackManipulation> manipulations = new ArrayList<>(properties.size() * 6 + 5);
352 for (Entry<StackManipulation, Method> entry : properties.entrySet()) {
353 // if (!java.util.(Objects|Arrays).equals(getFoo(), other.getFoo())) {
356 manipulations.add(THIS);
357 manipulations.add(entry.getKey());
358 manipulations.add(FIRST_ARG_REF);
359 manipulations.add(entry.getKey());
360 manipulations.add(entry.getValue().getReturnType().isArray() ? ARRAYS_EQUALS : OBJECTS_EQUALS);
361 manipulations.add(ifFalse);
365 manipulations.add(IntegerConstant.ONE);
366 manipulations.add(MethodReturn.INTEGER);
368 manipulations.add(ByteBuddyUtils.markLabel(falseLabel));
369 manipulations.add(IntegerConstant.ZERO);
370 manipulations.add(MethodReturn.INTEGER);
372 return new Implementation.Simple(manipulations.toArray(new StackManipulation[0]));
375 private static Implementation codecHashCode(final Class<?> bindingInterface) {
376 return new Implementation.Simple(
377 // return Foo.bindingHashCode(this);
379 invokeMethod(bindingInterface, BindingMapping.BINDING_HASHCODE_NAME, bindingInterface),
380 MethodReturn.INTEGER);
383 private static Implementation toString(final Class<?> bindingInterface) {
384 return new Implementation.Simple(
385 // return Foo.bindingToString(this);
387 invokeMethod(bindingInterface, BindingMapping.BINDING_TO_STRING_NAME, bindingInterface),
388 MethodReturn.REFERENCE);
391 private abstract static class AbstractMethodImplementation implements Implementation {
392 private static final Generic BB_HANDLE = TypeDefinition.Sort.describe(VarHandle.class);
393 private static final Generic BB_OBJECT = TypeDefinition.Sort.describe(Object.class);
394 private static final StackManipulation OBJECT_CLASS = ClassConstant.of(TypeDescription.OBJECT);
395 private static final StackManipulation LOOKUP = invokeMethod(MethodHandles.class, "lookup");
396 private static final StackManipulation FIND_VAR_HANDLE = invokeMethod(Lookup.class,
397 "findVarHandle", Class.class, String.class, Class.class);
399 static final int PRIV_CONST = Opcodes.ACC_PRIVATE | Opcodes.ACC_STATIC | Opcodes.ACC_FINAL
400 | Opcodes.ACC_SYNTHETIC;
401 private static final int PRIV_VOLATILE = Opcodes.ACC_PRIVATE | Opcodes.ACC_VOLATILE | Opcodes.ACC_SYNTHETIC;
403 final TypeDescription retType;
405 final String methodName;
407 final String handleName;
409 AbstractMethodImplementation(final String methodName, final TypeDescription retType) {
410 this.methodName = requireNonNull(methodName);
411 this.retType = requireNonNull(retType);
412 this.handleName = methodName + "$$$V";
416 public InstrumentedType prepare(final InstrumentedType instrumentedType) {
417 final InstrumentedType tmp = instrumentedType
418 // private static final VarHandle getFoo$$$V;
419 .withField(new FieldDescription.Token(handleName, PRIV_CONST, BB_HANDLE))
420 // private volatile Object getFoo;
421 .withField(new FieldDescription.Token(methodName, PRIV_VOLATILE, BB_OBJECT));
423 return tmp.withInitializer(new ByteCodeAppender.Simple(
424 // TODO: acquiring lookup is expensive, we should share it across all initialization
425 // getFoo$$$V = MethodHandles.lookup().findVarHandle(This.class, "getFoo", Object.class);
427 ClassConstant.of(tmp),
428 new TextConstant(methodName),
431 putField(tmp, handleName)));
435 private static final class KeyMethodImplementation extends AbstractMethodImplementation {
436 private static final StackManipulation CODEC_KEY = invokeMethod(CodecDataObject.class,
437 "codecKey", VarHandle.class);
439 KeyMethodImplementation(final String methodName, final TypeDescription retType) {
440 super(methodName, retType);
444 public ByteCodeAppender appender(final Target implementationTarget) {
445 return new ByteCodeAppender.Simple(
446 // return (FooType) codecKey(getFoo$$$V);
448 getField(implementationTarget.getInstrumentedType(), handleName),
450 TypeCasting.to(retType),
451 MethodReturn.REFERENCE);
456 * A simple leaf method, which looks up child by a String constant. This is slightly more complicated because we
457 * want to make sure we are using the same String instance as the one stored in associated DataObjectCodecContext,
458 * so that during lookup we perform an identity check instead of comparing content -- speeding things up as well
459 * as minimizing footprint. Since that string is not guaranteed to be interned in the String Pool, we cannot rely
460 * on the constant pool entry to resolve to the same object.
462 private static final class SimpleGetterMethodImplementation extends AbstractMethodImplementation {
463 private static final StackManipulation CODEC_MEMBER = invokeMethod(CodecDataObject.class,
464 "codecMember", VarHandle.class, String.class);
465 private static final StackManipulation BRIDGE_RESOLVE = invokeMethod(ClassGeneratorBridge.class,
466 "resolveLocalName", String.class);
467 private static final Generic BB_STRING = TypeDefinition.Sort.describe(String.class);
470 private final String stringName;
472 SimpleGetterMethodImplementation(final String methodName, final TypeDescription retType) {
473 super(methodName, retType);
474 this.stringName = methodName + "$$$S";
478 public InstrumentedType prepare(final InstrumentedType instrumentedType) {
479 final InstrumentedType tmp = super.prepare(instrumentedType)
480 // private static final String getFoo$$$S;
481 .withField(new FieldDescription.Token(stringName, PRIV_CONST, BB_STRING));
483 return tmp.withInitializer(new ByteCodeAppender.Simple(
484 // getFoo$$$S = CodecDataObjectBridge.resolveString("getFoo");
485 new TextConstant(methodName),
487 putField(tmp, stringName)));
491 public ByteCodeAppender appender(final Target implementationTarget) {
492 final TypeDescription instrumentedType = implementationTarget.getInstrumentedType();
493 return new ByteCodeAppender.Simple(
494 // return (FooType) codecMember(getFoo$$$V, getFoo$$$S);
496 getField(instrumentedType, handleName),
497 getField(instrumentedType, stringName),
499 TypeCasting.to(retType),
500 MethodReturn.REFERENCE);
504 private static final class StructuredGetterMethodImplementation extends AbstractMethodImplementation {
505 private static final StackManipulation CODEC_MEMBER = invokeMethod(CodecDataObject.class,
506 "codecMember", VarHandle.class, Class.class);
508 private final Class<?> bindingClass;
510 StructuredGetterMethodImplementation(final String methodName, final TypeDescription retType,
511 final Class<?> bindingClass) {
512 super(methodName, retType);
513 this.bindingClass = requireNonNull(bindingClass);
517 public ByteCodeAppender appender(final Target implementationTarget) {
518 return new ByteCodeAppender.Simple(
519 // return (FooType) codecMember(getFoo$$$V, FooType.class);
521 getField(implementationTarget.getInstrumentedType(), handleName),
522 ClassConstant.of(TypeDefinition.Sort.describe(bindingClass).asErasure()),
524 TypeCasting.to(retType),
525 MethodReturn.REFERENCE);
529 private static final class SupplierGetterMethodImplementation extends AbstractMethodImplementation {
530 private static final StackManipulation CODEC_MEMBER = invokeMethod(CodecDataObject.class,
531 "codecMember", VarHandle.class, NodeContextSupplier.class);
532 private static final StackManipulation BRIDGE_RESOLVE = invokeMethod(ClassGeneratorBridge.class,
533 "resolveNodeContextSupplier", String.class);
534 private static final Generic BB_NCS = TypeDefinition.Sort.describe(NodeContextSupplier.class);
537 private final String contextName;
539 SupplierGetterMethodImplementation(final String methodName, final TypeDescription retType) {
540 super(methodName, retType);
541 contextName = methodName + "$$$C";
545 public InstrumentedType prepare(final InstrumentedType instrumentedType) {
546 final InstrumentedType tmp = super.prepare(instrumentedType)
547 // private static final NodeContextSupplier getFoo$$$C;
548 .withField(new FieldDescription.Token(contextName, PRIV_CONST, BB_NCS));
550 return tmp.withInitializer(new ByteCodeAppender.Simple(
551 // getFoo$$$C = CodecDataObjectBridge.resolve("getFoo");
552 new TextConstant(methodName),
554 putField(tmp, contextName)));
558 public ByteCodeAppender appender(final Target implementationTarget) {
559 final TypeDescription instrumentedType = implementationTarget.getInstrumentedType();
560 return new ByteCodeAppender.Simple(
561 // return (FooType) codecMember(getFoo$$$V, getFoo$$$C);
563 getField(instrumentedType, handleName),
564 getField(instrumentedType, contextName),
566 TypeCasting.to(retType),
567 MethodReturn.REFERENCE);