Java Bootstrap类代码示例

import jdk.nashorn.internal.runtime.linker.Bootstrap; //导入依赖的package包/类
/**
 * ECMA 15.4.4.2 Array.prototype.toString ( )
 *
 * @param self self reference
 * @return string representation of array
 */
@Function(attributes = Attribute.NOT_ENUMERABLE)
public static Object toString(final Object self) {
    final Object obj = Global.toObject(self);
    if (obj instanceof ScriptObject) {
        final InvokeByName joinInvoker = getJOIN();
        final ScriptObject sobj = (ScriptObject)obj;
        try {
            final Object join = joinInvoker.getGetter().invokeExact(sobj);
            if (Bootstrap.isCallable(join)) {
                return joinInvoker.getInvoker().invokeExact(join, sobj);
            }
        } catch (final RuntimeException | Error e) {
            throw e;
        } catch (final Throwable t) {
            throw new RuntimeException(t);
        }
    }

    // FIXME: should lookup Object.prototype.toString and call that?
    return ScriptRuntime.builtinObjectToString(self);
}
 

import jdk.nashorn.internal.runtime.linker.Bootstrap; //导入依赖的package包/类
/**
 * ECMA 15.2.4.3 Object.prototype.toLocaleString ( )
 *
 * @param self self reference
 * @return localized ToString
 */
@Function(attributes = Attribute.NOT_ENUMERABLE)
public static Object toLocaleString(final Object self) {
    final Object obj = JSType.toScriptObject(self);
    if (obj instanceof ScriptObject) {
        final InvokeByName toStringInvoker = getTO_STRING();
        final ScriptObject sobj = (ScriptObject)self;
        try {
            final Object toString = toStringInvoker.getGetter().invokeExact(sobj);

            if (Bootstrap.isCallable(toString)) {
                return toStringInvoker.getInvoker().invokeExact(toString, sobj);
            }
        } catch (final RuntimeException | Error e) {
            throw e;
        } catch (final Throwable t) {
            throw new RuntimeException(t);
        }

        throw typeError("not.a.function", "toString");
    }

    return ScriptRuntime.builtinObjectToString(self);
}
 

import jdk.nashorn.internal.runtime.linker.Bootstrap; //导入依赖的package包/类
/**
 * Binds the source mirror object's properties to the target object. Binding
 * properties allows two-way read/write for the properties of the source object.
 * All inherited, enumerable properties are also bound. This method is used to
 * to make 'with' statement work with ScriptObjectMirror as scope object.
 *
 * @param target the target object to which the source object's properties are bound
 * @param source the source object whose properties are bound to the target
 * @return the target object after property binding
 */
public static Object bindAllProperties(final ScriptObject target, final ScriptObjectMirror source) {
    final Set<String> keys = source.keySet();
    // make accessor properties using dynamic invoker getters and setters
    final AccessorProperty[] props = new AccessorProperty[keys.size()];
    int idx = 0;
    for (final String name : keys) {
        final MethodHandle getter = Bootstrap.createDynamicInvoker("dyn:getMethod|getProp|getElem:" + name, MIRROR_GETTER_TYPE);
        final MethodHandle setter = Bootstrap.createDynamicInvoker("dyn:setProp|setElem:" + name, MIRROR_SETTER_TYPE);
        props[idx] = AccessorProperty.create(name, 0, getter, setter);
        idx++;
    }

    target.addBoundProperties(source, props);
    return target;
}
 

import jdk.nashorn.internal.runtime.linker.Bootstrap; //导入依赖的package包/类
/**
 * ECMA 15.5.4.11 String.prototype.replace (searchValue, replaceValue)
 * @param self        self reference
 * @param string      item to replace
 * @param replacement item to replace it with
 * @return string after replacement
 * @throws Throwable if replacement fails
 */
@Function(attributes = Attribute.NOT_ENUMERABLE)
public static String replace(final Object self, final Object string, final Object replacement) throws Throwable {

    final String str = checkObjectToString(self);

    final NativeRegExp nativeRegExp;
    if (string instanceof NativeRegExp) {
        nativeRegExp = (NativeRegExp) string;
    } else {
        nativeRegExp = NativeRegExp.flatRegExp(JSType.toString(string));
    }

    if (Bootstrap.isCallable(replacement)) {
        return nativeRegExp.replace(str, "", replacement);
    }

    return nativeRegExp.replace(str, JSType.toString(replacement), null);
}
 

import jdk.nashorn.internal.runtime.linker.Bootstrap; //导入依赖的package包/类
/**
 *
 * @param self the self reference
 * @param callbackFn the callback function
 * @param thisArg optional this-object
 */
@Function(attributes = Attribute.NOT_ENUMERABLE, arity = 1)
public static void forEach(final Object self, final Object callbackFn, final Object thisArg) {
    final NativeMap map = getNativeMap(self);
    if (!Bootstrap.isCallable(callbackFn)) {
        throw typeError("not.a.function", ScriptRuntime.safeToString(callbackFn));
    }
    final MethodHandle invoker = Global.instance().getDynamicInvoker(FOREACH_INVOKER_KEY,
            () -> Bootstrap.createDynamicCallInvoker(Object.class, Object.class, Object.class, Object.class, Object.class, Object.class));

    final LinkedMap.LinkedMapIterator iterator = map.getJavaMap().getIterator();
    for (;;) {
        final LinkedMap.Node node = iterator.next();
        if (node == null) {
            break;
        }

        try {
            final Object result = invoker.invokeExact(callbackFn, thisArg, node.getValue(), node.getKey(), self);
        } catch (final RuntimeException | Error e) {
            throw e;
        } catch (final Throwable t) {
            throw new RuntimeException(t);
        }
    }
}
 

import jdk.nashorn.internal.runtime.linker.Bootstrap; //导入依赖的package包/类
/**
 * ECMA6 23.2.3.6 Set.prototype.forEach ( callbackfn [ , thisArg ] )
 *
 * @param self the self reference
 * @param callbackFn the callback function
 * @param thisArg optional this object
 */
@Function(attributes = Attribute.NOT_ENUMERABLE, arity = 1)
public static void forEach(final Object self, final Object callbackFn, final Object thisArg) {
    final NativeSet set = getNativeSet(self);
    if (!Bootstrap.isCallable(callbackFn)) {
        throw typeError("not.a.function", ScriptRuntime.safeToString(callbackFn));
    }
    final MethodHandle invoker = Global.instance().getDynamicInvoker(FOREACH_INVOKER_KEY,
            () -> Bootstrap.createDynamicCallInvoker(Object.class, Object.class, Object.class, Object.class, Object.class, Object.class));

    final LinkedMap.LinkedMapIterator iterator = set.getJavaMap().getIterator();
    for (;;) {
        final LinkedMap.Node node = iterator.next();
        if (node == null) {
            break;
        }

        try {
            final Object result = invoker.invokeExact(callbackFn, thisArg, node.getKey(), node.getKey(), self);
        } catch (final RuntimeException | Error e) {
            throw e;
        } catch (final Throwable t) {
            throw new RuntimeException(t);
        }
    }
}
 

import jdk.nashorn.internal.runtime.linker.Bootstrap; //导入依赖的package包/类
/**
 * ECMA 15.2.4.3 Object.prototype.toLocaleString ( )
 *
 * @param self self reference
 * @return localized ToString
 */
@Function(attributes = Attribute.NOT_ENUMERABLE)
public static Object toLocaleString(final Object self) {
    final Object obj = JSType.toScriptObject(self);
    if (obj instanceof ScriptObject) {
        final InvokeByName toStringInvoker = getTO_STRING();
        final ScriptObject sobj = (ScriptObject)obj;
        try {
            final Object toString = toStringInvoker.getGetter().invokeExact(sobj);

            if (Bootstrap.isCallable(toString)) {
                return toStringInvoker.getInvoker().invokeExact(toString, sobj);
            }
        } catch (final RuntimeException | Error e) {
            throw e;
        } catch (final Throwable t) {
            throw new RuntimeException(t);
        }

        throw typeError("not.a.function", "toString");
    }

    return ScriptRuntime.builtinObjectToString(self);
}
 

import jdk.nashorn.internal.runtime.linker.Bootstrap; //导入依赖的package包/类
/**
 * Convert the given object to the given type.
 *
 * @param obj object to be converted
 * @param type destination type to convert to
 * @return converted object
 */
public static Object convert(final Object obj, final Object type) {
    if (obj == null) {
        return null;
    }

    final Class<?> clazz;
    if (type instanceof Class) {
        clazz = (Class<?>)type;
    } else if (type instanceof StaticClass) {
        clazz = ((StaticClass)type).getRepresentedClass();
    } else {
        throw new IllegalArgumentException("type expected");
    }

    final LinkerServices linker = Bootstrap.getLinkerServices();
    final Object objToConvert = unwrap(obj);
    final MethodHandle converter = linker.getTypeConverter(objToConvert.getClass(),  clazz);
    if (converter == null) {
        // no supported conversion!
        throw new UnsupportedOperationException("conversion not supported");
    }

    try {
        return converter.invoke(objToConvert);
    } catch (final RuntimeException | Error e) {
        throw e;
    } catch (final Throwable t) {
        throw new RuntimeException(t);
    }
}
 

import jdk.nashorn.internal.runtime.linker.Bootstrap; //导入依赖的package包/类
/**
 * ECMA 15.3.4.5 Function.prototype.bind (thisArg [, arg1 [, arg2, ...]])
 *
 * @param self self reference
 * @param args arguments for bind
 * @return function with bound arguments
 */
@Function(attributes = Attribute.NOT_ENUMERABLE, arity = 1)
public static Object bind(final Object self, final Object... args) {
    final Object thiz = (args.length == 0) ? UNDEFINED : args[0];

    Object[] arguments;
    if (args.length > 1) {
        arguments = new Object[args.length - 1];
        System.arraycopy(args, 1, arguments, 0, arguments.length);
    } else {
        arguments = ScriptRuntime.EMPTY_ARRAY;
    }

    return Bootstrap.bindCallable(self, thiz, arguments);
}
 

import jdk.nashorn.internal.runtime.linker.Bootstrap; //导入依赖的package包/类
private static MethodHandle getREPLACER_INVOKER() {
    return Global.instance().getDynamicInvoker(REPLACER_INVOKER,
            new Callable<MethodHandle>() {
                @Override
                public MethodHandle call() {
                    return Bootstrap.createDynamicInvoker("dyn:call", Object.class,
                        ScriptFunction.class, ScriptObject.class, Object.class, Object.class);
                }
            });
}
 

import jdk.nashorn.internal.runtime.linker.Bootstrap; //导入依赖的package包/类
private static MethodHandle createIteratorCallbackInvoker(final Object key, final Class<?> rtype) {
    return Global.instance().getDynamicInvoker(key,
        new Callable<MethodHandle>() {
            @Override
            public MethodHandle call() {
                return Bootstrap.createDynamicInvoker("dyn:call", rtype, Object.class, Object.class, Object.class,
                    long.class, Object.class);
            }
        });
}
 

import jdk.nashorn.internal.runtime.linker.Bootstrap; //导入依赖的package包/类
private static MethodHandle getREDUCE_CALLBACK_INVOKER() {
    return Global.instance().getDynamicInvoker(REDUCE_CALLBACK_INVOKER,
            new Callable<MethodHandle>() {
                @Override
                public MethodHandle call() {
                    return Bootstrap.createDynamicInvoker("dyn:call", Object.class, Object.class,
                         Undefined.class, Object.class, Object.class, long.class, Object.class);
                }
            });
}
 

import jdk.nashorn.internal.runtime.linker.Bootstrap; //导入依赖的package包/类
private static MethodHandle getCALL_CMP() {
    return Global.instance().getDynamicInvoker(CALL_CMP,
            new Callable<MethodHandle>() {
                @Override
                public MethodHandle call() {
                    return Bootstrap.createDynamicInvoker("dyn:call", double.class,
                        ScriptFunction.class, Object.class, Object.class, Object.class);
                }
            });
}
 

import jdk.nashorn.internal.runtime.linker.Bootstrap; //导入依赖的package包/类
/**
 * ECMA 15.9.5.44 Date.prototype.toJSON ( key )
 *
 * Provides a string representation of this Date for use by {@link NativeJSON#stringify(Object, Object, Object, Object)}
 *
 * @param self self reference
 * @param key ignored
 * @return JSON representation of this date
 */
@Function(attributes = Attribute.NOT_ENUMERABLE)
public static Object toJSON(final Object self, final Object key) {
    // NOTE: Date.prototype.toJSON is generic. Accepts other objects as well.
    final Object selfObj = Global.toObject(self);
    if (!(selfObj instanceof ScriptObject)) {
        return null;
    }
    final ScriptObject sobj  = (ScriptObject)selfObj;
    final Object       value = sobj.getDefaultValue(Number.class);
    if (value instanceof Number) {
        final double num = ((Number)value).doubleValue();
        if (isInfinite(num) || isNaN(num)) {
            return null;
        }
    }

    try {
        final InvokeByName toIsoString = getTO_ISO_STRING();
        final Object func = toIsoString.getGetter().invokeExact(sobj);
        if (Bootstrap.isCallable(func)) {
            return toIsoString.getInvoker().invokeExact(func, sobj, key);
        }
        throw typeError("not.a.function", ScriptRuntime.safeToString(func));
    } catch (final RuntimeException | Error e) {
        throw e;
    } catch (final Throwable t) {
        throw new RuntimeException(t);
    }
}
 

import jdk.nashorn.internal.runtime.linker.Bootstrap; //导入依赖的package包/类
private static MethodHandle getBoundBeanMethodGetter(final Object source, final MethodHandle methodGetter) {
    try {
        // NOTE: we're relying on the fact that "dyn:getMethod:..." return value is constant for any given method
        // name and object linked with BeansLinker. (Actually, an even stronger assumption is true: return value is
        // constant for any given method name and object's class.)
        return MethodHandles.dropArguments(MethodHandles.constant(Object.class,
                Bootstrap.bindCallable(methodGetter.invoke(source), source, null)), 0, Object.class);
    } catch(RuntimeException|Error e) {
        throw e;
    } catch(final Throwable t) {
        throw new RuntimeException(t);
    }
}