/*
* Copyright 2009 Google Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may not
* use this file except in compliance with the License. You may obtain a copy of
* the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations under
* the License.
*/
package com.google.gwt.dev.jjs.impl;
import com.google.gwt.dev.jjs.ast.JArrayType;
import com.google.gwt.dev.jjs.ast.JClassType;
import com.google.gwt.dev.jjs.ast.JConstructor;
import com.google.gwt.dev.jjs.ast.JDeclaredType;
import com.google.gwt.dev.jjs.ast.JField;
import com.google.gwt.dev.jjs.ast.JMethod;
import com.google.gwt.dev.jjs.ast.JNode;
import com.google.gwt.dev.jjs.ast.JParameter;
import com.google.gwt.dev.jjs.ast.JPrimitiveType;
import com.google.gwt.dev.jjs.ast.JProgram;
import com.google.gwt.dev.jjs.ast.JType;
import com.google.gwt.dev.util.JsniRef;
import java.util.LinkedHashMap;
import java.util.LinkedHashSet;
import java.util.Set;
import java.util.TreeSet;
/**
* A utility class that can look up a {@link JsniRef} in a {@link JProgram}.
*
* @deprecated find alternatives, only a couple of corner cases use this now.
*/
@Deprecated
public class JsniRefLookup {
/**
* A callback used to indicate the reason for a failed JSNI lookup.
*/
public interface ErrorReporter {
void reportError(String error);
}
/**
* Look up a JSNI reference.
*
* @param ref The reference to look up
* @param program The program to look up the reference in
* @param errorReporter A callback used to indicate the reason for a failed
* JSNI lookup
* @return The item referred to, or <code>null</code> if it could not be
* found. If the return value is <code>null</code>,
* <code>errorReporter</code> will have been invoked.
*/
public static JNode findJsniRefTarget(JsniRef ref, JProgram program,
JsniRefLookup.ErrorReporter errorReporter) {
String className = ref.className();
JType type = null;
if (!className.equals("null")) {
type = program.getTypeFromJsniRef(className);
if (type == null) {
errorReporter.reportError("Unresolvable native reference to type '" + className + "'");
return null;
}
}
if (!ref.isMethod()) {
// look for a field
String fieldName = ref.memberName();
if (type == null) {
if (fieldName.equals("nullField")) {
return program.getNullField();
}
} else if (fieldName.equals(JsniRef.CLASS)) {
return type;
} else if (type instanceof JPrimitiveType) {
errorReporter.reportError("May not refer to fields on primitive types");
return null;
} else if (type instanceof JArrayType) {
errorReporter.reportError("May not refer to fields on array types");
return null;
} else {
for (JField field : ((JDeclaredType) type).getFields()) {
if (field.getName().equals(fieldName)) {
return field;
}
}
}
errorReporter.reportError("Unresolvable native reference to field '" + fieldName
+ "' in type '" + className + "'");
return null;
} else if (type instanceof JPrimitiveType) {
errorReporter.reportError("May not refer to methods on primitive types");
return null;
} else {
// look for a method
LinkedHashMap<String, LinkedHashMap<String, JMethod>> matchesBySig =
new LinkedHashMap<String, LinkedHashMap<String, JMethod>>();
String methodName = ref.memberName();
String jsniSig = ref.memberSignature();
if (type == null) {
if (jsniSig.equals("nullMethod()")) {
return program.getNullMethod();
}
} else {
findMostDerivedMembers(matchesBySig, (JDeclaredType) type, methodName, true);
LinkedHashMap<String, JMethod> matches = matchesBySig.get(jsniSig);
if (matches != null && matches.size() == 1) {
/*
* Backward compatibility: allow accessing bridge methods with full
* qualification
*/
return matches.values().iterator().next();
}
removeSyntheticMembers(matchesBySig);
matches = matchesBySig.get(jsniSig);
if (matches != null && matches.size() == 1) {
return matches.values().iterator().next();
}
}
// Not found; signal an error
if (matchesBySig.isEmpty()) {
errorReporter.reportError("Unresolvable native reference to method '" + methodName
+ "' in type '" + className + "'");
return null;
} else {
StringBuilder suggestList = new StringBuilder();
String comma = "";
// use a TreeSet to sort the near matches
TreeSet<String> almostMatchSigs = new TreeSet<String>();
for (String sig : matchesBySig.keySet()) {
if (matchesBySig.get(sig).size() == 1) {
almostMatchSigs.add(sig);
}
}
for (String almost : almostMatchSigs) {
suggestList.append(comma + "'" + almost + "'");
comma = ", ";
}
errorReporter.reportError("Unresolvable native reference to method '" + methodName
+ "' in type '" + className + "' (did you mean " + suggestList.toString() + "?)");
return null;
}
}
}
/**
* Add a member to the table of most derived members.
*
* @param matchesBySig The table so far of most derived members
* @param member The member to add to it
* @param refSig The string used to refer to that member, possibly shortened
* @param fullSig The fully qualified signature for that member
*/
private static void addMember(LinkedHashMap<String, LinkedHashMap<String, JMethod>> matchesBySig,
JMethod member, String refSig, String fullSig) {
LinkedHashMap<String, JMethod> matchesByFullSig = matchesBySig.get(refSig);
if (matchesByFullSig == null) {
matchesByFullSig = new LinkedHashMap<String, JMethod>();
matchesBySig.put(refSig, matchesByFullSig);
}
matchesByFullSig.put(fullSig, member);
}
/**
* For each member with the given name, find the most derived members for each
* JSNI reference that match it. For wildcard JSNI references, there will in
* general be more than one match. This method does not ignore synthetic
* methods.
*/
private static void findMostDerivedMembers(
LinkedHashMap<String, LinkedHashMap<String, JMethod>> matchesBySig, JDeclaredType targetType,
String memberName, boolean addConstructorsAndPrivates) {
/*
* Analyze superclasses and interfaces first. More derived members will thus
* be seen later.
*/
if (targetType instanceof JClassType) {
JClassType targetClass = (JClassType) targetType;
if (targetClass.getSuperClass() != null) {
findMostDerivedMembers(matchesBySig, targetClass.getSuperClass(), memberName, false);
}
}
for (JDeclaredType intf : targetType.getImplements()) {
findMostDerivedMembers(matchesBySig, intf, memberName, false);
}
// Get the methods on this class/interface.
for (JMethod method : targetType.getMethods()) {
if (method instanceof JConstructor && JsniRef.NEW.equals(memberName)) {
if (!addConstructorsAndPrivates) {
continue;
}
StringBuilder sb = new StringBuilder();
sb.append(JsniRef.NEW);
sb.append("(");
for (JParameter param : method.getParams()) {
sb.append(param.getType().getJsniSignatureName());
}
sb.append(")");
String fullSig = sb.toString();
String wildcardSig = JsniRef.NEW + "(" + JsniRef.WILDCARD_PARAM_LIST + ")";
addMember(matchesBySig, method, fullSig, fullSig);
addMember(matchesBySig, method, wildcardSig, fullSig);
} else if (method.getName().equals(memberName)) {
if (!addConstructorsAndPrivates && method.isPrivate()) {
continue;
}
String fullSig = JProgram.getJsniSig(method, false);
String wildcardSig = method.getName() + "(" + JsniRef.WILDCARD_PARAM_LIST + ")";
addMember(matchesBySig, method, fullSig, fullSig);
addMember(matchesBySig, method, wildcardSig, fullSig);
}
}
}
private static void removeSyntheticMembers(
LinkedHashMap<String, LinkedHashMap<String, JMethod>> matchesBySig) {
for (LinkedHashMap<String, JMethod> matchesByFullSig : matchesBySig.values()) {
Set<String> toRemove = new LinkedHashSet<String>();
for (String fullSig : matchesByFullSig.keySet()) {
JMethod member = matchesByFullSig.get(fullSig);
if (member.isSynthetic()) {
toRemove.add(fullSig);
}
}
for (String fullSig : toRemove) {
matchesByFullSig.remove(fullSig);
}
}
}
}