org.mozilla.javascript.JavaMembers Maven / Gradle / Ivy
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/* -*- Mode: java; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
package org.mozilla.javascript;
import java.lang.reflect.*;
import java.util.*;
import static java.lang.reflect.Modifier.isProtected;
import static java.lang.reflect.Modifier.isPublic;
/**
*
* @author Mike Shaver
* @author Norris Boyd
* @see NativeJavaObject
* @see NativeJavaClass
*/
class JavaMembers
{
JavaMembers(Scriptable scope, Class cl)
{
this(scope, cl, false);
}
JavaMembers(Scriptable scope, Class cl, boolean includeProtected)
{
try {
Context cx = ContextFactory.getGlobal().enterContext();
ClassShutter shutter = cx.getClassShutter();
if (shutter != null && !shutter.visibleToScripts(cl.getName())) {
throw Context.reportRuntimeError1("msg.access.prohibited",
cl.getName());
}
this.members = new HashMap();
this.staticMembers = new HashMap();
this.cl = cl;
boolean includePrivate = cx.hasFeature(
Context.FEATURE_ENHANCED_JAVA_ACCESS);
reflect(scope, includeProtected, includePrivate);
} finally {
Context.exit();
}
}
boolean has(String name, boolean isStatic)
{
Map ht = isStatic ? staticMembers : members;
Object obj = ht.get(name);
if (obj != null) {
return true;
}
return findExplicitFunction(name, isStatic) != null;
}
Object get(Scriptable scope, String name, Object javaObject,
boolean isStatic)
{
Map ht = isStatic ? staticMembers : members;
Object member = ht.get(name);
if (!isStatic && member == null) {
// Try to get static member from instance (LC3)
member = staticMembers.get(name);
}
if (member == null) {
member = this.getExplicitFunction(scope, name,
javaObject, isStatic);
if (member == null)
return Scriptable.NOT_FOUND;
}
if (member instanceof Scriptable) {
return member;
}
Context cx = Context.getContext();
Object rval;
Class type;
try {
if (member instanceof BeanProperty) {
BeanProperty bp = (BeanProperty) member;
if (bp.getter == null)
return Scriptable.NOT_FOUND;
rval = bp.getter.invoke(javaObject, Context.emptyArgs);
type = bp.getter.method().getReturnType();
} else {
Field field = (Field) member;
rval = field.get(isStatic ? null : javaObject);
type = field.getType();
}
} catch (Exception ex) {
throw Context.throwAsScriptRuntimeEx(ex);
}
// Need to wrap the object before we return it.
scope = ScriptableObject.getTopLevelScope(scope);
return cx.getWrapFactory().wrap(cx, scope, rval, type);
}
void put(Scriptable scope, String name, Object javaObject,
Object value, boolean isStatic)
{
Map ht = isStatic ? staticMembers : members;
Object member = ht.get(name);
if (!isStatic && member == null) {
// Try to get static member from instance (LC3)
member = staticMembers.get(name);
}
if (member == null)
throw reportMemberNotFound(name);
if (member instanceof FieldAndMethods) {
FieldAndMethods fam = (FieldAndMethods) ht.get(name);
member = fam.field;
}
// Is this a bean property "set"?
if (member instanceof BeanProperty) {
BeanProperty bp = (BeanProperty)member;
if (bp.setter == null) {
throw reportMemberNotFound(name);
}
// If there's only one setter or if the value is null, use the
// main setter. Otherwise, let the NativeJavaMethod decide which
// setter to use:
if (bp.setters == null || value == null) {
Class setType = bp.setter.argTypes[0];
Object[] args = { Context.jsToJava(value, setType) };
try {
bp.setter.invoke(javaObject, args);
} catch (Exception ex) {
throw Context.throwAsScriptRuntimeEx(ex);
}
} else {
Object[] args = { value };
bp.setters.call(Context.getContext(),
ScriptableObject.getTopLevelScope(scope),
scope, args);
}
}
else {
if (!(member instanceof Field)) {
String str = (member == null) ? "msg.java.internal.private"
: "msg.java.method.assign";
throw Context.reportRuntimeError1(str, name);
}
Field field = (Field)member;
Object javaValue = Context.jsToJava(value, field.getType());
try {
field.set(javaObject, javaValue);
} catch (IllegalAccessException accessEx) {
if ((field.getModifiers() & Modifier.FINAL) != 0) {
// treat Java final the same as JavaScript [[READONLY]]
return;
}
throw Context.throwAsScriptRuntimeEx(accessEx);
} catch (IllegalArgumentException argEx) {
throw Context.reportRuntimeError3(
"msg.java.internal.field.type",
value.getClass().getName(), field,
javaObject.getClass().getName());
}
}
}
Object[] getIds(boolean isStatic)
{
Map map = isStatic ? staticMembers : members;
return map.keySet().toArray(new Object[map.size()]);
}
static String javaSignature(Class type)
{
if (!type.isArray()) {
return type.getName();
} else {
int arrayDimension = 0;
do {
++arrayDimension;
type = type.getComponentType();
} while (type.isArray());
String name = type.getName();
String suffix = "[]";
if (arrayDimension == 1) {
return name.concat(suffix);
} else {
int length = name.length() + arrayDimension * suffix.length();
StringBuilder sb = new StringBuilder(length);
sb.append(name);
while (arrayDimension != 0) {
--arrayDimension;
sb.append(suffix);
}
return sb.toString();
}
}
}
static String liveConnectSignature(Class[] argTypes)
{
int N = argTypes.length;
if (N == 0) { return "()"; }
StringBuilder sb = new StringBuilder();
sb.append('(');
for (int i = 0; i != N; ++i) {
if (i != 0) {
sb.append(',');
}
sb.append(javaSignature(argTypes[i]));
}
sb.append(')');
return sb.toString();
}
private MemberBox findExplicitFunction(String name, boolean isStatic)
{
int sigStart = name.indexOf('(');
if (sigStart < 0) { return null; }
Map ht = isStatic ? staticMembers : members;
MemberBox[] methodsOrCtors = null;
boolean isCtor = (isStatic && sigStart == 0);
if (isCtor) {
// Explicit request for an overloaded constructor
methodsOrCtors = ctors.methods;
} else {
// Explicit request for an overloaded method
String trueName = name.substring(0,sigStart);
Object obj = ht.get(trueName);
if (!isStatic && obj == null) {
// Try to get static member from instance (LC3)
obj = staticMembers.get(trueName);
}
if (obj instanceof NativeJavaMethod) {
NativeJavaMethod njm = (NativeJavaMethod)obj;
methodsOrCtors = njm.methods;
}
}
if (methodsOrCtors != null) {
for (MemberBox methodsOrCtor : methodsOrCtors) {
Class[] type = methodsOrCtor.argTypes;
String sig = liveConnectSignature(type);
if (sigStart + sig.length() == name.length()
&& name.regionMatches(sigStart, sig, 0, sig.length()))
{
return methodsOrCtor;
}
}
}
return null;
}
private Object getExplicitFunction(Scriptable scope, String name,
Object javaObject, boolean isStatic)
{
Map ht = isStatic ? staticMembers : members;
Object member = null;
MemberBox methodOrCtor = findExplicitFunction(name, isStatic);
if (methodOrCtor != null) {
Scriptable prototype =
ScriptableObject.getFunctionPrototype(scope);
if (methodOrCtor.isCtor()) {
NativeJavaConstructor fun =
new NativeJavaConstructor(methodOrCtor);
fun.setPrototype(prototype);
member = fun;
ht.put(name, fun);
} else {
String trueName = methodOrCtor.getName();
member = ht.get(trueName);
if (member instanceof NativeJavaMethod &&
((NativeJavaMethod)member).methods.length > 1 ) {
NativeJavaMethod fun =
new NativeJavaMethod(methodOrCtor, name);
fun.setPrototype(prototype);
ht.put(name, fun);
member = fun;
}
}
}
return member;
}
/**
* Retrieves mapping of methods to accessible methods for a class.
* In case the class is not public, retrieves methods with same
* signature as its public methods from public superclasses and
* interfaces (if they exist). Basically upcasts every method to the
* nearest accessible method.
*/
private static Method[] discoverAccessibleMethods(Class clazz,
boolean includeProtected,
boolean includePrivate)
{
Map map = new HashMap();
discoverAccessibleMethods(clazz, map, includeProtected, includePrivate);
return map.values().toArray(new Method[map.size()]);
}
private static void discoverAccessibleMethods(Class clazz,
Map map, boolean includeProtected,
boolean includePrivate)
{
if (isPublic(clazz.getModifiers()) || includePrivate) {
try {
if (includeProtected || includePrivate) {
while (clazz != null) {
try {
Method[] methods = clazz.getDeclaredMethods();
for (Method method : methods) {
int mods = method.getModifiers();
if (isPublic(mods)
|| isProtected(mods)
|| includePrivate) {
MethodSignature sig = new MethodSignature(method);
if (!map.containsKey(sig)) {
if (includePrivate && !method.isAccessible())
method.setAccessible(true);
map.put(sig, method);
}
}
}
clazz = clazz.getSuperclass();
} catch (SecurityException e) {
// Some security settings (i.e., applets) disallow
// access to Class.getDeclaredMethods. Fall back to
// Class.getMethods.
Method[] methods = clazz.getMethods();
for (Method method : methods) {
MethodSignature sig = new MethodSignature(method);
if (!map.containsKey(sig))
map.put(sig, method);
}
break; // getMethods gets superclass methods, no
// need to loop any more
}
}
} else {
Method[] methods = clazz.getMethods();
for (Method method : methods) {
MethodSignature sig = new MethodSignature(method);
// Array may contain methods with same signature but different return value!
if (!map.containsKey(sig))
map.put(sig, method);
}
}
return;
} catch (SecurityException e) {
Context.reportWarning(
"Could not discover accessible methods of class " +
clazz.getName() + " due to lack of privileges, " +
"attemping superclasses/interfaces.");
// Fall through and attempt to discover superclass/interface
// methods
}
}
Class[] interfaces = clazz.getInterfaces();
for (Class intface : interfaces) {
discoverAccessibleMethods(intface, map, includeProtected,
includePrivate);
}
Class superclass = clazz.getSuperclass();
if (superclass != null) {
discoverAccessibleMethods(superclass, map, includeProtected,
includePrivate);
}
}
private static final class MethodSignature
{
private final String name;
private final Class[] args;
private MethodSignature(String name, Class[] args)
{
this.name = name;
this.args = args;
}
MethodSignature(Method method)
{
this(method.getName(), method.getParameterTypes());
}
@Override
public boolean equals(Object o)
{
if(o instanceof MethodSignature)
{
MethodSignature ms = (MethodSignature)o;
return ms.name.equals(name) && Arrays.equals(args, ms.args);
}
return false;
}
@Override
public int hashCode()
{
return name.hashCode() ^ args.length;
}
}
private void reflect(Scriptable scope,
boolean includeProtected,
boolean includePrivate)
{
// We reflect methods first, because we want overloaded field/method
// names to be allocated to the NativeJavaMethod before the field
// gets in the way.
Method[] methods = discoverAccessibleMethods(cl, includeProtected,
includePrivate);
for (Method method : methods) {
int mods = method.getModifiers();
boolean isStatic = Modifier.isStatic(mods);
Map ht = isStatic ? staticMembers : members;
String name = method.getName();
Object value = ht.get(name);
if (value == null) {
ht.put(name, method);
} else {
ObjArray overloadedMethods;
if (value instanceof ObjArray) {
overloadedMethods = (ObjArray)value;
} else {
if (!(value instanceof Method)) Kit.codeBug();
// value should be instance of Method as at this stage
// staticMembers and members can only contain methods
overloadedMethods = new ObjArray();
overloadedMethods.add(value);
ht.put(name, overloadedMethods);
}
overloadedMethods.add(method);
}
}
// replace Method instances by wrapped NativeJavaMethod objects
// first in staticMembers and then in members
for (int tableCursor = 0; tableCursor != 2; ++tableCursor) {
boolean isStatic = (tableCursor == 0);
Map ht = isStatic ? staticMembers : members;
for (Map.Entry entry: ht.entrySet()) {
MemberBox[] methodBoxes;
Object value = entry.getValue();
if (value instanceof Method) {
methodBoxes = new MemberBox[1];
methodBoxes[0] = new MemberBox((Method)value);
} else {
ObjArray overloadedMethods = (ObjArray)value;
int N = overloadedMethods.size();
if (N < 2) Kit.codeBug();
methodBoxes = new MemberBox[N];
for (int i = 0; i != N; ++i) {
Method method = (Method)overloadedMethods.get(i);
methodBoxes[i] = new MemberBox(method);
}
}
NativeJavaMethod fun = new NativeJavaMethod(methodBoxes);
if (scope != null) {
ScriptRuntime.setFunctionProtoAndParent(fun, scope);
}
ht.put(entry.getKey(), fun);
}
}
// Reflect fields.
Field[] fields = getAccessibleFields(includeProtected, includePrivate);
for (Field field : fields) {
String name = field.getName();
int mods = field.getModifiers();
try {
boolean isStatic = Modifier.isStatic(mods);
Map ht = isStatic ? staticMembers : members;
Object member = ht.get(name);
if (member == null) {
ht.put(name, field);
} else if (member instanceof NativeJavaMethod) {
NativeJavaMethod method = (NativeJavaMethod) member;
FieldAndMethods fam
= new FieldAndMethods(scope, method.methods, field);
Map fmht = isStatic ? staticFieldAndMethods
: fieldAndMethods;
if (fmht == null) {
fmht = new HashMap();
if (isStatic) {
staticFieldAndMethods = fmht;
} else {
fieldAndMethods = fmht;
}
}
fmht.put(name, fam);
ht.put(name, fam);
} else if (member instanceof Field) {
Field oldField = (Field) member;
// If this newly reflected field shadows an inherited field,
// then replace it. Otherwise, since access to the field
// would be ambiguous from Java, no field should be
// reflected.
// For now, the first field found wins, unless another field
// explicitly shadows it.
if (oldField.getDeclaringClass().
isAssignableFrom(field.getDeclaringClass()))
{
ht.put(name, field);
}
} else {
// "unknown member type"
Kit.codeBug();
}
} catch (SecurityException e) {
// skip this field
Context.reportWarning("Could not access field "
+ name + " of class " + cl.getName() +
" due to lack of privileges.");
}
}
// Create bean properties from corresponding get/set methods first for
// static members and then for instance members
for (int tableCursor = 0; tableCursor != 2; ++tableCursor) {
boolean isStatic = (tableCursor == 0);
Map ht = isStatic ? staticMembers : members;
Map toAdd = new HashMap();
// Now, For each member, make "bean" properties.
for (String name: ht.keySet()) {
// Is this a getter?
boolean memberIsGetMethod = name.startsWith("get");
boolean memberIsSetMethod = name.startsWith("set");
boolean memberIsIsMethod = name.startsWith("is");
if (memberIsGetMethod || memberIsIsMethod
|| memberIsSetMethod) {
// Double check name component.
String nameComponent
= name.substring(memberIsIsMethod ? 2 : 3);
if (nameComponent.length() == 0)
continue;
// Make the bean property name.
String beanPropertyName = nameComponent;
char ch0 = nameComponent.charAt(0);
if (Character.isUpperCase(ch0)) {
if (nameComponent.length() == 1) {
beanPropertyName = nameComponent.toLowerCase();
} else {
char ch1 = nameComponent.charAt(1);
if (!Character.isUpperCase(ch1)) {
beanPropertyName = Character.toLowerCase(ch0)
+nameComponent.substring(1);
}
}
}
// If we already have a member by this name, don't do this
// property.
if (toAdd.containsKey(beanPropertyName))
continue;
Object v = ht.get(beanPropertyName);
if (v != null) {
// A private field shouldn't mask a public getter/setter
if (!includePrivate || !(v instanceof Member) ||
!Modifier.isPrivate(((Member)v).getModifiers()))
{
continue;
}
}
// Find the getter method, or if there is none, the is-
// method.
MemberBox getter = null;
getter = findGetter(isStatic, ht, "get", nameComponent);
// If there was no valid getter, check for an is- method.
if (getter == null) {
getter = findGetter(isStatic, ht, "is", nameComponent);
}
// setter
MemberBox setter = null;
NativeJavaMethod setters = null;
String setterName = "set".concat(nameComponent);
if (ht.containsKey(setterName)) {
// Is this value a method?
Object member = ht.get(setterName);
if (member instanceof NativeJavaMethod) {
NativeJavaMethod njmSet = (NativeJavaMethod)member;
if (getter != null) {
// We have a getter. Now, do we have a matching
// setter?
Class type = getter.method().getReturnType();
setter = extractSetMethod(type, njmSet.methods,
isStatic);
} else {
// No getter, find any set method
setter = extractSetMethod(njmSet.methods,
isStatic);
}
if (njmSet.methods.length > 1) {
setters = njmSet;
}
}
}
// Make the property.
BeanProperty bp = new BeanProperty(getter, setter,
setters);
toAdd.put(beanPropertyName, bp);
}
}
// Add the new bean properties.
for (String key: toAdd.keySet()) {
Object value = toAdd.get(key);
ht.put(key, value);
}
}
// Reflect constructors
Constructor[] constructors = getAccessibleConstructors(includePrivate);
MemberBox[] ctorMembers = new MemberBox[constructors.length];
for (int i = 0; i != constructors.length; ++i) {
ctorMembers[i] = new MemberBox(constructors[i]);
}
ctors = new NativeJavaMethod(ctorMembers, cl.getSimpleName());
}
private Constructor[] getAccessibleConstructors(boolean includePrivate)
{
// The JVM currently doesn't allow changing access on java.lang.Class
// constructors, so don't try
if (includePrivate && cl != ScriptRuntime.ClassClass) {
try {
Constructor[] cons = cl.getDeclaredConstructors();
AccessibleObject.setAccessible(cons, true);
return cons;
} catch (SecurityException e) {
// Fall through to !includePrivate case
Context.reportWarning("Could not access constructor " +
" of class " + cl.getName() +
" due to lack of privileges.");
}
}
return cl.getConstructors();
}
private Field[] getAccessibleFields(boolean includeProtected,
boolean includePrivate) {
if (includePrivate || includeProtected) {
try {
List fieldsList = new ArrayList();
Class currentClass = cl;
while (currentClass != null) {
// get all declared fields in this class, make them
// accessible, and save
Field[] declared = currentClass.getDeclaredFields();
for (Field field : declared) {
int mod = field.getModifiers();
if (includePrivate || isPublic(mod) || isProtected(mod)) {
if (!field.isAccessible())
field.setAccessible(true);
fieldsList.add(field);
}
}
// walk up superclass chain. no need to deal specially with
// interfaces, since they can't have fields
currentClass = currentClass.getSuperclass();
}
return fieldsList.toArray(new Field[fieldsList.size()]);
} catch (SecurityException e) {
// fall through to !includePrivate case
}
}
return cl.getFields();
}
private MemberBox findGetter(boolean isStatic, Map ht, String prefix,
String propertyName)
{
String getterName = prefix.concat(propertyName);
if (ht.containsKey(getterName)) {
// Check that the getter is a method.
Object member = ht.get(getterName);
if (member instanceof NativeJavaMethod) {
NativeJavaMethod njmGet = (NativeJavaMethod) member;
return extractGetMethod(njmGet.methods, isStatic);
}
}
return null;
}
private static MemberBox extractGetMethod(MemberBox[] methods,
boolean isStatic)
{
// Inspect the list of all MemberBox for the only one having no
// parameters
for (MemberBox method : methods) {
// Does getter method have an empty parameter list with a return
// value (eg. a getSomething() or isSomething())?
if (method.argTypes.length == 0 && (!isStatic || method.isStatic())) {
Class type = method.method().getReturnType();
if (type != Void.TYPE) {
return method;
}
break;
}
}
return null;
}
private static MemberBox extractSetMethod(Class type, MemberBox[] methods,
boolean isStatic)
{
//
// Note: it may be preferable to allow NativeJavaMethod.findFunction()
// to find the appropriate setter; unfortunately, it requires an
// instance of the target arg to determine that.
//
// Make two passes: one to find a method with direct type assignment,
// and one to find a widening conversion.
for (int pass = 1; pass <= 2; ++pass) {
for (MemberBox method : methods) {
if (!isStatic || method.isStatic()) {
Class[] params = method.argTypes;
if (params.length == 1) {
if (pass == 1) {
if (params[0] == type) {
return method;
}
} else {
if (pass != 2) Kit.codeBug();
if (params[0].isAssignableFrom(type)) {
return method;
}
}
}
}
}
}
return null;
}
private static MemberBox extractSetMethod(MemberBox[] methods,
boolean isStatic)
{
for (MemberBox method : methods) {
if (!isStatic || method.isStatic()) {
if (method.method().getReturnType() == Void.TYPE) {
if (method.argTypes.length == 1) {
return method;
}
}
}
}
return null;
}
Map getFieldAndMethodsObjects(Scriptable scope,
Object javaObject, boolean isStatic)
{
Map ht = isStatic ? staticFieldAndMethods : fieldAndMethods;
if (ht == null)
return null;
int len = ht.size();
Map result = new HashMap(len);
for (FieldAndMethods fam: ht.values()) {
FieldAndMethods famNew = new FieldAndMethods(scope, fam.methods,
fam.field);
famNew.javaObject = javaObject;
result.put(fam.field.getName(), famNew);
}
return result;
}
static JavaMembers lookupClass(Scriptable scope, Class dynamicType,
Class staticType, boolean includeProtected)
{
JavaMembers members;
ClassCache cache = ClassCache.get(scope);
Map,JavaMembers> ct = cache.getClassCacheMap();
Class cl = dynamicType;
for (;;) {
members = ct.get(cl);
if (members != null) {
if (cl != dynamicType) {
// member lookup for the original class failed because of
// missing privileges, cache the result so we don't try again
ct.put(dynamicType, members);
}
return members;
}
try {
members = new JavaMembers(cache.getAssociatedScope(), cl,
includeProtected);
break;
} catch (SecurityException e) {
// Reflection may fail for objects that are in a restricted
// access package (e.g. sun.*). If we get a security
// exception, try again with the static type if it is interface.
// Otherwise, try superclass
if (staticType != null && staticType.isInterface()) {
cl = staticType;
staticType = null; // try staticType only once
} else {
Class parent = cl.getSuperclass();
if (parent == null) {
if (cl.isInterface()) {
// last resort after failed staticType interface
parent = ScriptRuntime.ObjectClass;
} else {
throw e;
}
}
cl = parent;
}
}
}
if (cache.isCachingEnabled()) {
ct.put(cl, members);
if (cl != dynamicType) {
// member lookup for the original class failed because of
// missing privileges, cache the result so we don't try again
ct.put(dynamicType, members);
}
}
return members;
}
RuntimeException reportMemberNotFound(String memberName)
{
return Context.reportRuntimeError2(
"msg.java.member.not.found", cl.getName(), memberName);
}
private Class cl;
private Map members;
private Map fieldAndMethods;
private Map staticMembers;
private Map staticFieldAndMethods;
NativeJavaMethod ctors; // we use NativeJavaMethod for ctor overload resolution
}
class BeanProperty
{
BeanProperty(MemberBox getter, MemberBox setter, NativeJavaMethod setters)
{
this.getter = getter;
this.setter = setter;
this.setters = setters;
}
MemberBox getter;
MemberBox setter;
NativeJavaMethod setters;
}
class FieldAndMethods extends NativeJavaMethod
{
static final long serialVersionUID = -9222428244284796755L;
FieldAndMethods(Scriptable scope, MemberBox[] methods, Field field)
{
super(methods);
this.field = field;
setParentScope(scope);
setPrototype(ScriptableObject.getFunctionPrototype(scope));
}
@Override
public Object getDefaultValue(Class hint)
{
if (hint == ScriptRuntime.FunctionClass)
return this;
Object rval;
Class type;
try {
rval = field.get(javaObject);
type = field.getType();
} catch (IllegalAccessException accEx) {
throw Context.reportRuntimeError1(
"msg.java.internal.private", field.getName());
}
Context cx = Context.getContext();
rval = cx.getWrapFactory().wrap(cx, this, rval, type);
if (rval instanceof Scriptable) {
rval = ((Scriptable) rval).getDefaultValue(hint);
}
return rval;
}
Field field;
Object javaObject;
}