jdk.internal.dynalink.support.CallSiteDescriptorFactory Java Examples

private GuardedInvocation lookup(final CallSiteDescriptor desc, final LinkRequest request, final LinkerServices linkerServices) throws Exception {
    final String operator = CallSiteDescriptorFactory.tokenizeOperators(desc).get(0);
    final int c = desc.getNameTokenCount();

    switch (operator) {
        case "getProp":
        case "getElem":
        case "getMethod":
            if (c > 2) {
                return findGetMethod(desc);
            }
        // For indexed get, we want get GuardedInvocation beans linker and pass it.
        // JSObjectLinker.get uses this fallback getter for explicit signature method access.
        return findGetIndexMethod(nashornBeansLinker.getGuardedInvocation(request, linkerServices));
        case "setProp":
        case "setElem":
            return c > 2 ? findSetMethod(desc) : findSetIndexMethod();
        case "call":
            return findCallMethod(desc);
        case "new":
            return findNewMethod(desc);
        default:
            return null;
    }
}
 

private GuardedInvocation lookup(final CallSiteDescriptor desc, final LinkRequest request, final LinkerServices linkerServices) throws Exception {
    final String operator = CallSiteDescriptorFactory.tokenizeOperators(desc).get(0);
    final int c = desc.getNameTokenCount();
    GuardedInvocation inv;
    try {
        inv = nashornBeansLinker.getGuardedInvocation(request, linkerServices);
    } catch (Throwable th) {
        inv = null;
    }

    switch (operator) {
        case "getProp":
        case "getElem":
        case "getMethod":
            return c > 2? findGetMethod(desc, inv) : findGetIndexMethod(inv);
        case "setProp":
        case "setElem":
            return c > 2? findSetMethod(desc, inv) : findSetIndexMethod();
        case "call":
            return findCallMethod(desc);
        default:
            return null;
    }
}
 

private static GuardedInvocation lookup(final CallSiteDescriptor desc) {
    final String operator = CallSiteDescriptorFactory.tokenizeOperators(desc).get(0);
    final int c = desc.getNameTokenCount();
    switch (operator) {
        case "getProp":
        case "getElem":
        case "getMethod":
            return c > 2 ? findGetMethod(desc) : findGetIndexMethod();
        case "setProp":
        case "setElem":
            return c > 2 ? findSetMethod(desc) : findSetIndexMethod();
        case "call":
            return findCallMethod(desc);
        case "new":
            return findNewMethod(desc);
        default:
            return null;
    }
}
 

@Override
public GuardedInvocation getGuardedInvocation(LinkRequest linkRequest, LinkerServices linkerServices) {
    final Object receiver = linkRequest.getReceiver();
    if(!(receiver instanceof DynamicMethod)) {
        return null;
    }
    final CallSiteDescriptor desc = linkRequest.getCallSiteDescriptor();
    if(desc.getNameTokenCount() != 2 && desc.getNameToken(CallSiteDescriptor.SCHEME) != "dyn") {
        return null;
    }
    final String operator = desc.getNameToken(CallSiteDescriptor.OPERATOR);
    if(operator == "call") {
        final MethodHandle invocation = ((DynamicMethod)receiver).getInvocation(
                CallSiteDescriptorFactory.dropParameterTypes(desc, 0, 1), linkerServices);
        if(invocation == null) {
            return null;
        }
        return new GuardedInvocation(MethodHandles.dropArguments(invocation, 0,
                desc.getMethodType().parameterType(0)), Guards.getIdentityGuard(receiver));
    }
    return null;
}
 

private static void checkLinkRequest(final LinkRequest origRequest) {
    final SecurityManager sm = System.getSecurityManager();
    if (sm != null) {
        final LinkRequest requestWithoutContext = origRequest.withoutRuntimeContext(); // Nashorn has no runtime context
        final Object self = requestWithoutContext.getReceiver();
        // allow 'static' access on Class objects representing public classes of non-restricted packages
        if ((self instanceof Class) && Modifier.isPublic(((Class<?>)self).getModifiers())) {
            final CallSiteDescriptor desc = requestWithoutContext.getCallSiteDescriptor();
            if(CallSiteDescriptorFactory.tokenizeOperators(desc).contains("getProp")) {
                if ("static".equals(desc.getNameToken(CallSiteDescriptor.NAME_OPERAND))) {
                    if (Context.isAccessibleClass((Class<?>)self) && !isReflectionClass((Class<?>)self)) {

                        // If "getProp:static" passes access checks, allow access.
                        return;
                    }
                }
            }
        }
        checkReflectionPermission(sm);
    }
}
 

@Override
public GuardedInvocation getGuardedInvocation(final LinkRequest request, final LinkerServices linkerServices)
        throws Exception {
    final LinkRequest ncrequest = request.withoutRuntimeContext();
    // BeansLinker already checked that the name is at least 2 elements long and the first element is "dyn".
    final CallSiteDescriptor callSiteDescriptor = ncrequest.getCallSiteDescriptor();
    final String op = callSiteDescriptor.getNameToken(CallSiteDescriptor.OPERATOR);
    // Either dyn:callMethod:name(this[,args]) or dyn:callMethod(this,name[,args]).
    if("callMethod" == op) {
        return getCallPropWithThis(callSiteDescriptor, linkerServices);
    }
    List<String> operations = CallSiteDescriptorFactory.tokenizeOperators(callSiteDescriptor);
    while(!operations.isEmpty()) {
        final GuardedInvocationComponent gic = getGuardedInvocationComponent(callSiteDescriptor, linkerServices,
                operations);
        if(gic != null) {
            return gic.getGuardedInvocation();
        }
        operations = pop(operations);
    }
    return null;
}
 

private static GuardedInvocation lookup(final CallSiteDescriptor desc) {
    final String operator = CallSiteDescriptorFactory.tokenizeOperators(desc).get(0);
    final int c = desc.getNameTokenCount();
    switch (operator) {
        case "getProp":
        case "getElem":
        case "getMethod":
            return c > 2 ? findGetMethod(desc) : findGetIndexMethod();
        case "setProp":
        case "setElem":
            return c > 2 ? findSetMethod(desc) : findSetIndexMethod();
        case "call":
            return findCallMethod(desc, operator);
        case "callMethod":
            return findCallMethodMethod(desc, operator);
        case "new":
            return findNewMethod(desc);
        default:
            return null;
    }
}
 

@Override
public GuardedInvocation getGuardedInvocation(LinkRequest request, final LinkerServices linkerServices)
        throws Exception {
    final LinkRequest ncrequest = request.withoutRuntimeContext();
    // BeansLinker already checked that the name is at least 2 elements long and the first element is "dyn".
    final CallSiteDescriptor callSiteDescriptor = ncrequest.getCallSiteDescriptor();
    final String op = callSiteDescriptor.getNameToken(CallSiteDescriptor.OPERATOR);
    // Either dyn:callMethod:name(this[,args]) or dyn:callMethod(this,name[,args]).
    if("callMethod" == op) {
        return getCallPropWithThis(callSiteDescriptor, linkerServices);
    }
    List<String> operations = CallSiteDescriptorFactory.tokenizeOperators(callSiteDescriptor);
    while(!operations.isEmpty()) {
        final GuardedInvocationComponent gic = getGuardedInvocationComponent(callSiteDescriptor, linkerServices,
                operations);
        if(gic != null) {
            return gic.getGuardedInvocation();
        }
        operations = pop(operations);
    }
    return null;
}
 

@Override
public GuardedInvocation getGuardedInvocation(LinkRequest linkRequest, LinkerServices linkerServices) {
    final Object receiver = linkRequest.getReceiver();
    if(!(receiver instanceof DynamicMethod)) {
        return null;
    }
    final CallSiteDescriptor desc = linkRequest.getCallSiteDescriptor();
    if(desc.getNameTokenCount() != 2 && desc.getNameToken(CallSiteDescriptor.SCHEME) != "dyn") {
        return null;
    }
    final String operator = desc.getNameToken(CallSiteDescriptor.OPERATOR);
    if(operator == "call") {
        final MethodHandle invocation = ((DynamicMethod)receiver).getInvocation(
                CallSiteDescriptorFactory.dropParameterTypes(desc, 0, 1), linkerServices);
        if(invocation == null) {
            return null;
        }
        return new GuardedInvocation(MethodHandles.dropArguments(invocation, 0,
                desc.getMethodType().parameterType(0)), Guards.getIdentityGuard(receiver));
    }
    return null;
}
 

@Override
public GuardedInvocation getGuardedInvocation(LinkRequest request, final LinkerServices linkerServices)
        throws Exception {
    final LinkRequest ncrequest = request.withoutRuntimeContext();
    // BeansLinker already checked that the name is at least 2 elements long and the first element is "dyn".
    final CallSiteDescriptor callSiteDescriptor = ncrequest.getCallSiteDescriptor();
    final String op = callSiteDescriptor.getNameToken(CallSiteDescriptor.OPERATOR);
    // Either dyn:callMethod:name(this[,args]) or dyn:callMethod(this,name[,args]).
    if("callMethod" == op) {
        return getCallPropWithThis(callSiteDescriptor, linkerServices);
    }
    List<String> operations = CallSiteDescriptorFactory.tokenizeOperators(callSiteDescriptor);
    while(!operations.isEmpty()) {
        final GuardedInvocationComponent gic = getGuardedInvocationComponent(callSiteDescriptor, linkerServices,
                operations);
        if(gic != null) {
            return gic.getGuardedInvocation();
        }
        operations = pop(operations);
    }
    return null;
}
 

private GuardedInvocation lookup(final CallSiteDescriptor desc, final LinkRequest request, final LinkerServices linkerServices) throws Exception {
    final String operator = CallSiteDescriptorFactory.tokenizeOperators(desc).get(0);
    final int c = desc.getNameTokenCount();

    switch (operator) {
        case "getProp":
        case "getElem":
        case "getMethod":
            if (c > 2) {
                return findGetMethod(desc);
            }
        // For indexed get, we want get GuardedInvocation beans linker and pass it.
        // JSObjectLinker.get uses this fallback getter for explicit signature method access.
        return findGetIndexMethod(nashornBeansLinker.getGuardedInvocation(request, linkerServices));
        case "setProp":
        case "setElem":
            return c > 2 ? findSetMethod(desc) : findSetIndexMethod();
        case "call":
            return findCallMethod(desc);
        case "new":
            return findNewMethod(desc);
        default:
            return null;
    }
}
 

private GuardedInvocation lookup(final CallSiteDescriptor desc, final LinkRequest request, final LinkerServices linkerServices) throws Exception {
    final String operator = CallSiteDescriptorFactory.tokenizeOperators(desc).get(0);
    final int c = desc.getNameTokenCount();
    GuardedInvocation inv;
    try {
        inv = nashornBeansLinker.getGuardedInvocation(request, linkerServices);
    } catch (Throwable th) {
        inv = null;
    }

    switch (operator) {
        case "getProp":
        case "getElem":
        case "getMethod":
            return c > 2? findGetMethod(desc, inv) : findGetIndexMethod(inv);
        case "setProp":
        case "setElem":
            return c > 2? findSetMethod(desc, inv) : findSetIndexMethod();
        case "call":
            return findCallMethod(desc);
        default:
            return null;
    }
}
 

private GuardedInvocation lookup(final CallSiteDescriptor desc, final LinkRequest request, final LinkerServices linkerServices) throws Exception {
    final String operator = CallSiteDescriptorFactory.tokenizeOperators(desc).get(0);
    final int c = desc.getNameTokenCount();

    switch (operator) {
        case "getProp":
        case "getElem":
        case "getMethod":
            if (c > 2) {
                return findGetMethod(desc);
            }
        // For indexed get, we want get GuardedInvocation beans linker and pass it.
        // JSObjectLinker.get uses this fallback getter for explicit signature method access.
        return findGetIndexMethod(nashornBeansLinker.getGuardedInvocation(request, linkerServices));
        case "setProp":
        case "setElem":
            return c > 2 ? findSetMethod(desc) : findSetIndexMethod();
        case "call":
            return findCallMethod(desc);
        case "new":
            return findNewMethod(desc);
        default:
            return null;
    }
}
 

private static GuardedInvocation lookup(final CallSiteDescriptor desc) {
    final String operator = CallSiteDescriptorFactory.tokenizeOperators(desc).get(0);
    final int c = desc.getNameTokenCount();
    switch (operator) {
        case "getProp":
        case "getElem":
        case "getMethod":
            return c > 2 ? findGetMethod(desc) : findGetIndexMethod();
        case "setProp":
        case "setElem":
            return c > 2 ? findSetMethod(desc) : findSetIndexMethod();
        case "call":
            return findCallMethod(desc);
        case "new":
            return findNewMethod(desc);
        default:
            return null;
    }
}
 

private static void checkLinkRequest(final LinkRequest origRequest) {
    final SecurityManager sm = System.getSecurityManager();
    if (sm != null) {
        final LinkRequest requestWithoutContext = origRequest.withoutRuntimeContext(); // Nashorn has no runtime context
        final Object self = requestWithoutContext.getReceiver();
        // allow 'static' access on Class objects representing public classes of non-restricted packages
        if ((self instanceof Class) && Modifier.isPublic(((Class<?>)self).getModifiers())) {
            final CallSiteDescriptor desc = requestWithoutContext.getCallSiteDescriptor();
            if(CallSiteDescriptorFactory.tokenizeOperators(desc).contains("getProp")) {
                if ("static".equals(desc.getNameToken(CallSiteDescriptor.NAME_OPERAND))) {
                    if (Context.isAccessibleClass((Class<?>)self) && !isReflectionClass((Class<?>)self)) {

                        // If "getProp:static" passes access checks, allow access.
                        return;
                    }
                }
            }
        }
        checkReflectionPermission(sm);
    }
}
 

@Override
public GuardedInvocation getGuardedInvocation(final LinkRequest request, final LinkerServices linkerServices)
        throws Exception {
    final LinkRequest ncrequest = request.withoutRuntimeContext();
    // BeansLinker already checked that the name is at least 2 elements long and the first element is "dyn".
    final CallSiteDescriptor callSiteDescriptor = ncrequest.getCallSiteDescriptor();
    final String op = callSiteDescriptor.getNameToken(CallSiteDescriptor.OPERATOR);
    // Either dyn:callMethod:name(this[,args]) or dyn:callMethod(this,name[,args]).
    if("callMethod" == op) {
        return getCallPropWithThis(callSiteDescriptor, linkerServices);
    }
    List<String> operations = CallSiteDescriptorFactory.tokenizeOperators(callSiteDescriptor);
    while(!operations.isEmpty()) {
        final GuardedInvocationComponent gic = getGuardedInvocationComponent(callSiteDescriptor, linkerServices,
                operations);
        if(gic != null) {
            return gic.getGuardedInvocation();
        }
        operations = pop(operations);
    }
    return null;
}
 

@Override
public GuardedInvocation getGuardedInvocation(LinkRequest linkRequest, LinkerServices linkerServices) {
    final Object receiver = linkRequest.getReceiver();
    if(!(receiver instanceof DynamicMethod)) {
        return null;
    }
    final CallSiteDescriptor desc = linkRequest.getCallSiteDescriptor();
    if(desc.getNameTokenCount() != 2 && desc.getNameToken(CallSiteDescriptor.SCHEME) != "dyn") {
        return null;
    }
    final String operator = desc.getNameToken(CallSiteDescriptor.OPERATOR);
    if(operator == "call") {
        final MethodHandle invocation = ((DynamicMethod)receiver).getInvocation(
                CallSiteDescriptorFactory.dropParameterTypes(desc, 0, 1), linkerServices);
        if(invocation == null) {
            return null;
        }
        return new GuardedInvocation(MethodHandles.dropArguments(invocation, 0,
                desc.getMethodType().parameterType(0)), Guards.getIdentityGuard(receiver));
    }
    return null;
}
 

private GuardedInvocation lookup(final CallSiteDescriptor desc, final LinkRequest request, final LinkerServices linkerServices) throws Exception {
    final String operator = CallSiteDescriptorFactory.tokenizeOperators(desc).get(0);
    final int c = desc.getNameTokenCount();

    switch (operator) {
        case "getProp":
        case "getElem":
        case "getMethod":
            if (c > 2) {
                return findGetMethod(desc);
            }
        // For indexed get, we want get GuardedInvocation beans linker and pass it.
        // JSObjectLinker.get uses this fallback getter for explicit signature method access.
        return findGetIndexMethod(nashornBeansLinker.getGuardedInvocation(request, linkerServices));
        case "setProp":
        case "setElem":
            return c > 2 ? findSetMethod(desc) : findSetIndexMethod();
        case "call":
            return findCallMethod(desc);
        case "new":
            return findNewMethod(desc);
        default:
            return null;
    }
}
 

@Override
public GuardedInvocation getGuardedInvocation(final LinkRequest request, final LinkerServices linkerServices)
        throws Exception {
    final LinkRequest ncrequest = request.withoutRuntimeContext();
    // BeansLinker already checked that the name is at least 2 elements long and the first element is "dyn".
    final CallSiteDescriptor callSiteDescriptor = ncrequest.getCallSiteDescriptor();
    final String op = callSiteDescriptor.getNameToken(CallSiteDescriptor.OPERATOR);
    // Either dyn:callMethod:name(this[,args]) or dyn:callMethod(this,name[,args]).
    if("callMethod" == op) {
        return getCallPropWithThis(callSiteDescriptor, linkerServices);
    }
    List<String> operations = CallSiteDescriptorFactory.tokenizeOperators(callSiteDescriptor);
    while(!operations.isEmpty()) {
        final GuardedInvocationComponent gic = getGuardedInvocationComponent(callSiteDescriptor, linkerServices,
                operations);
        if(gic != null) {
            return gic.getGuardedInvocation();
        }
        operations = pop(operations);
    }
    return null;
}
 

private GuardedInvocation lookup(final CallSiteDescriptor desc, final LinkRequest request, final LinkerServices linkerServices) throws Exception {
    final String operator = CallSiteDescriptorFactory.tokenizeOperators(desc).get(0);
    final int c = desc.getNameTokenCount();

    switch (operator) {
        case "getProp":
        case "getElem":
        case "getMethod":
            if (c > 2) {
                return findGetMethod(desc);
            }
        // For indexed get, we want get GuardedInvocation beans linker and pass it.
        // JSObjectLinker.get uses this fallback getter for explicit signature method access.
        return findGetIndexMethod(nashornBeansLinker.getGuardedInvocation(request, linkerServices));
        case "setProp":
        case "setElem":
            return c > 2 ? findSetMethod(desc) : findSetIndexMethod();
        case "call":
            return findCallMethod(desc);
        case "new":
            return findNewMethod(desc);
        default:
            return null;
    }
}
 

@Override
public GuardedInvocation getGuardedInvocation(LinkRequest request, final LinkerServices linkerServices)
        throws Exception {
    final LinkRequest ncrequest = request.withoutRuntimeContext();
    // BeansLinker already checked that the name is at least 2 elements long and the first element is "dyn".
    final CallSiteDescriptor callSiteDescriptor = ncrequest.getCallSiteDescriptor();
    final String op = callSiteDescriptor.getNameToken(CallSiteDescriptor.OPERATOR);
    // Either dyn:callMethod:name(this[,args]) or dyn:callMethod(this,name[,args]).
    if("callMethod" == op) {
        return getCallPropWithThis(callSiteDescriptor, linkerServices);
    }
    List<String> operations = CallSiteDescriptorFactory.tokenizeOperators(callSiteDescriptor);
    while(!operations.isEmpty()) {
        final GuardedInvocationComponent gic = getGuardedInvocationComponent(callSiteDescriptor, linkerServices,
                operations);
        if(gic != null) {
            return gic.getGuardedInvocation();
        }
        operations = pop(operations);
    }
    return null;
}
 

private GuardedInvocation lookup(final CallSiteDescriptor desc, final LinkRequest request, final LinkerServices linkerServices) throws Exception {
    final String operator = CallSiteDescriptorFactory.tokenizeOperators(desc).get(0);
    final int c = desc.getNameTokenCount();
    GuardedInvocation inv;
    try {
        inv = nashornBeansLinker.getGuardedInvocation(request, linkerServices);
    } catch (Throwable th) {
        inv = null;
    }

    switch (operator) {
        case "getProp":
        case "getElem":
        case "getMethod":
            return c > 2? findGetMethod(desc, inv) : findGetIndexMethod(inv);
        case "setProp":
        case "setElem":
            return c > 2? findSetMethod(desc, inv) : findSetIndexMethod();
        case "call":
            return findCallMethod(desc);
        default:
            return null;
    }
}
 

@Override
public GuardedInvocation getGuardedInvocation(final LinkRequest request, final LinkerServices linkerServices)
        throws Exception {
    final LinkRequest ncrequest = request.withoutRuntimeContext();
    // BeansLinker already checked that the name is at least 2 elements long and the first element is "dyn".
    final CallSiteDescriptor callSiteDescriptor = ncrequest.getCallSiteDescriptor();
    final String op = callSiteDescriptor.getNameToken(CallSiteDescriptor.OPERATOR);
    // Either dyn:callMethod:name(this[,args]) or dyn:callMethod(this,name[,args]).
    if("callMethod" == op) {
        return getCallPropWithThis(callSiteDescriptor, linkerServices);
    }
    List<String> operations = CallSiteDescriptorFactory.tokenizeOperators(callSiteDescriptor);
    while(!operations.isEmpty()) {
        final GuardedInvocationComponent gic = getGuardedInvocationComponent(callSiteDescriptor, linkerServices,
                operations);
        if(gic != null) {
            return gic.getGuardedInvocation();
        }
        operations = pop(operations);
    }
    return null;
}
 

private static void checkLinkRequest(final LinkRequest origRequest) {
    final SecurityManager sm = System.getSecurityManager();
    if (sm != null) {
        final LinkRequest requestWithoutContext = origRequest.withoutRuntimeContext(); // Nashorn has no runtime context
        final Object self = requestWithoutContext.getReceiver();
        // allow 'static' access on Class objects representing public classes of non-restricted packages
        if ((self instanceof Class) && Modifier.isPublic(((Class<?>)self).getModifiers())) {
            final CallSiteDescriptor desc = requestWithoutContext.getCallSiteDescriptor();
            if(CallSiteDescriptorFactory.tokenizeOperators(desc).contains("getProp")) {
                if ("static".equals(desc.getNameToken(CallSiteDescriptor.NAME_OPERAND))) {
                    if (Context.isAccessibleClass((Class<?>)self) && !isReflectionClass((Class<?>)self)) {
                        // If "getProp:static" passes access checks, allow access.
                        return;
                    }
                }
            }
        }
        checkReflectionPermission(sm);
    }
}
 

private GuardedInvocation lookup(final CallSiteDescriptor desc, final LinkRequest request, final LinkerServices linkerServices) throws Exception {
    final String operator = CallSiteDescriptorFactory.tokenizeOperators(desc).get(0);
    final int c = desc.getNameTokenCount();
    GuardedInvocation inv;
    try {
        inv = nashornBeansLinker.getGuardedInvocation(request, linkerServices);
    } catch (Throwable th) {
        inv = null;
    }

    switch (operator) {
        case "getProp":
        case "getElem":
        case "getMethod":
            return c > 2? findGetMethod(desc, inv) : findGetIndexMethod(inv);
        case "setProp":
        case "setElem":
            return c > 2? findSetMethod(desc, inv) : findSetIndexMethod();
        case "call":
            return findCallMethod(desc);
        default:
            return null;
    }
}
 

@Override
public GuardedInvocation getGuardedInvocation(final LinkRequest linkRequest, final LinkerServices linkerServices) {
    final Object receiver = linkRequest.getReceiver();
    if(!(receiver instanceof DynamicMethod)) {
        return null;
    }
    final CallSiteDescriptor desc = linkRequest.getCallSiteDescriptor();
    if(desc.getNameTokenCount() != 2 && desc.getNameToken(CallSiteDescriptor.SCHEME) != "dyn") {
        return null;
    }
    final String operator = desc.getNameToken(CallSiteDescriptor.OPERATOR);
    final DynamicMethod dynMethod = (DynamicMethod)receiver;
    final boolean constructor = dynMethod.isConstructor();
    final MethodHandle invocation;

    if (operator == "call" && !constructor) {
        invocation = dynMethod.getInvocation(
                CallSiteDescriptorFactory.dropParameterTypes(desc, 0, 1), linkerServices);
    } else if (operator == "new" && constructor) {
        final MethodHandle ctorInvocation = dynMethod.getInvocation(desc, linkerServices);
        if(ctorInvocation == null) {
            return null;
        }

        // Insert null for StaticClass parameter
        invocation = MethodHandles.insertArguments(ctorInvocation, 0, (Object)null);
    } else {
        return null;
    }

    if (invocation != null) {
        return new GuardedInvocation(MethodHandles.dropArguments(invocation, 0,
            desc.getMethodType().parameterType(0)), Guards.getIdentityGuard(receiver));
    }

    return null;
}
 

@Override
public GuardedInvocation getGuardedInvocation(final LinkRequest linkRequest, final LinkerServices linkerServices) {
    final Object receiver = linkRequest.getReceiver();
    if(!(receiver instanceof DynamicMethod)) {
        return null;
    }
    final CallSiteDescriptor desc = linkRequest.getCallSiteDescriptor();
    if(desc.getNameTokenCount() != 2 && desc.getNameToken(CallSiteDescriptor.SCHEME) != "dyn") {
        return null;
    }
    final String operator = desc.getNameToken(CallSiteDescriptor.OPERATOR);
    final DynamicMethod dynMethod = (DynamicMethod)receiver;
    final boolean constructor = dynMethod.isConstructor();
    final MethodHandle invocation;

    if (operator == "call" && !constructor) {
        invocation = dynMethod.getInvocation(
                CallSiteDescriptorFactory.dropParameterTypes(desc, 0, 1), linkerServices);
    } else if (operator == "new" && constructor) {
        final MethodHandle ctorInvocation = dynMethod.getInvocation(desc, linkerServices);
        if(ctorInvocation == null) {
            return null;
        }

        // Insert null for StaticClass parameter
        invocation = MethodHandles.insertArguments(ctorInvocation, 0, (Object)null);
    } else {
        return null;
    }

    if (invocation != null) {
        return new GuardedInvocation(MethodHandles.dropArguments(invocation, 0,
            desc.getMethodType().parameterType(0)), Guards.getIdentityGuard(receiver));
    }

    return null;
}
 

/**
 * Lookup method that, given a CallSiteDescriptor, looks up the target
 * MethodHandle and creates a GuardedInvocation
 * with the appropriate guard(s).
 *
 * @param desc call site descriptor
 * @param request the link request
 *
 * @return GuardedInvocation for the callsite
 */
public GuardedInvocation lookup(final CallSiteDescriptor desc, final LinkRequest request) {
    final int c = desc.getNameTokenCount();
    // JavaScript is "immune" to all currently defined Dynalink composite operation - getProp is the same as getElem
    // is the same as getMethod as JavaScript objects have a single namespace for all three. Therefore, we don't
    // care about them, and just link to whatever is the first operation.
    final String operator = CallSiteDescriptorFactory.tokenizeOperators(desc).get(0);
    // NOTE: we support getElem and setItem as JavaScript doesn't distinguish items from properties. Nashorn itself
    // emits "dyn:getProp:identifier" for "<expr>.<identifier>" and "dyn:getElem" for "<expr>[<expr>]", but we are
    // more flexible here and dispatch not on operation name (getProp vs. getElem), but rather on whether the
    // operation has an associated name or not.
    switch (operator) {
    case "getProp":
    case "getElem":
    case "getMethod":
        return c > 2 ? findGetMethod(desc, request, operator) : findGetIndexMethod(desc, request);
    case "setProp":
    case "setElem":
        return c > 2 ? findSetMethod(desc, request) : findSetIndexMethod(desc, request);
    case "call":
        return findCallMethod(desc, request);
    case "new":
        return findNewMethod(desc, request);
    case "callMethod":
        return findCallMethodMethod(desc, request);
    default:
        return null;
    }
}
 

/**
 * Lookup the appropriate method for an invoke dynamic call.
 * @param desc The invoke dynamic callsite descriptor.
 * @return GuardedInvocation to be invoked at call site.
 */
public static GuardedInvocation lookup(final CallSiteDescriptor desc) {
    final String operator = CallSiteDescriptorFactory.tokenizeOperators(desc).get(0);

    switch (operator) {
    case "new":
    case "call":
        throw lookupTypeError("cant.call.undefined", desc);
    case "callMethod":
        throw lookupTypeError("cant.read.property.of.undefined", desc);
    // NOTE: we support getElem and setItem as JavaScript doesn't distinguish items from properties. Nashorn itself
    // emits "dyn:getProp:identifier" for "<expr>.<identifier>" and "dyn:getElem" for "<expr>[<expr>]", but we are
    // more flexible here and dispatch not on operation name (getProp vs. getElem), but rather on whether the
    // operation has an associated name or not.
    case "getProp":
    case "getElem":
    case "getMethod":
        if (desc.getNameTokenCount() < 3) {
            return findGetIndexMethod(desc);
        }
        throw lookupTypeError("cant.read.property.of.undefined", desc);
    case "setProp":
    case "setElem":
        if (desc.getNameTokenCount() < 3) {
            return findSetIndexMethod(desc);
        }
        throw lookupTypeError("cant.set.property.of.undefined", desc);
    default:
        break;
    }

    return null;
}
 

/**
 * Lookup method that, given a CallSiteDescriptor, looks up the target
 * MethodHandle and creates a GuardedInvocation
 * with the appropriate guard(s).
 *
 * @param desc call site descriptor
 * @param request the link request
 *
 * @return GuardedInvocation for the callsite
 */
public GuardedInvocation lookup(final CallSiteDescriptor desc, final LinkRequest request) {
    final int c = desc.getNameTokenCount();
    // JavaScript is "immune" to all currently defined Dynalink composite operation - getProp is the same as getElem
    // is the same as getMethod as JavaScript objects have a single namespace for all three. Therefore, we don't
    // care about them, and just link to whatever is the first operation.
    final String operator = CallSiteDescriptorFactory.tokenizeOperators(desc).get(0);
    // NOTE: we support getElem and setItem as JavaScript doesn't distinguish items from properties. Nashorn itself
    // emits "dyn:getProp:identifier" for "<expr>.<identifier>" and "dyn:getElem" for "<expr>[<expr>]", but we are
    // more flexible here and dispatch not on operation name (getProp vs. getElem), but rather on whether the
    // operation has an associated name or not.
    switch (operator) {
    case "getProp":
    case "getElem":
    case "getMethod":
        return c > 2 ? findGetMethod(desc, request, operator) : findGetIndexMethod(desc, request);
    case "setProp":
    case "setElem":
        return c > 2 ? findSetMethod(desc, request) : findSetIndexMethod(desc);
    case "call":
        return findCallMethod(desc, request);
    case "new":
        return findNewMethod(desc);
    case "callMethod":
        return findCallMethodMethod(desc, request);
    default:
        return null;
    }
}