/*
* Copyright (C) 2012 The Android Open Source Project
*
* 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.android.tools.klint.checks;
import static com.android.SdkConstants.CLASS_VIEW;
import static com.android.tools.klint.checks.CleanupDetector.CURSOR_CLS;
import com.android.annotations.NonNull;
import com.android.annotations.Nullable;
import com.android.tools.klint.client.api.JavaEvaluator;
import com.android.tools.klint.detector.api.Category;
import com.android.tools.klint.detector.api.Detector;
import com.android.tools.klint.detector.api.Implementation;
import com.android.tools.klint.detector.api.Issue;
import com.android.tools.klint.detector.api.JavaContext;
import com.android.tools.klint.detector.api.Scope;
import com.android.tools.klint.detector.api.Severity;
import com.android.tools.klint.detector.api.TypeEvaluator;
import com.intellij.psi.PsiClass;
import com.intellij.psi.PsiClassType;
import com.intellij.psi.PsiType;
import com.intellij.psi.util.InheritanceUtil;
import org.jetbrains.uast.UCallExpression;
import org.jetbrains.uast.UExpression;
import org.jetbrains.uast.UMethod;
import org.jetbrains.uast.visitor.UastVisitor;
import java.util.Collections;
import java.util.List;
/**
* Checks for missing view tag detectors
*/
public class ViewTagDetector extends Detector implements Detector.UastScanner {
/** Using setTag and leaking memory */
public static final Issue ISSUE = Issue.create(
"ViewTag", //$NON-NLS-1$
"Tagged object leaks",
"Prior to Android 4.0, the implementation of `View.setTag(int, Object)` would " +
"store the objects in a static map, where the values were strongly referenced. " +
"This means that if the object contains any references pointing back to the " +
"context, the context (which points to pretty much everything else) will leak. " +
"If you pass a view, the view provides a reference to the context " +
"that created it. Similarly, view holders typically contain a view, and cursors " +
"are sometimes also associated with views.",
Category.PERFORMANCE,
6,
Severity.WARNING,
new Implementation(
ViewTagDetector.class,
Scope.JAVA_FILE_SCOPE));
/** Constructs a new {@link ViewTagDetector} */
public ViewTagDetector() {
}
// ---- Implements JavaScanner ----
@Nullable
@Override
public List<String> getApplicableMethodNames() {
return Collections.singletonList("setTag");
}
@Override
public void visitMethod(@NonNull JavaContext context, @Nullable UastVisitor visitor,
@NonNull UCallExpression call, @NonNull UMethod method) {
// The leak behavior is fixed in ICS:
// http://code.google.com/p/android/issues/detail?id=18273
if (context.getMainProject().getMinSdk() >= 14) {
return;
}
JavaEvaluator evaluator = context.getEvaluator();
if (!evaluator.isMemberInSubClassOf(method, CLASS_VIEW, false)) {
return;
}
List<UExpression> arguments = call.getValueArguments();
if (arguments.size() != 2) {
return;
}
UExpression tagArgument = arguments.get(1);
if (tagArgument == null) {
return;
}
PsiType type = TypeEvaluator.evaluate(context, tagArgument);
if ((!(type instanceof PsiClassType))) {
return;
}
PsiClass typeClass = ((PsiClassType) type).resolve();
if (typeClass == null) {
return;
}
String objectType;
if (InheritanceUtil.isInheritor(typeClass, false, CLASS_VIEW)) {
objectType = "views";
} else if (InheritanceUtil.isInheritor(typeClass, false, CURSOR_CLS)) {
objectType = "cursors";
} else if (typeClass.getName() != null && typeClass.getName().endsWith("ViewHolder")) {
objectType = "view holders";
} else {
return;
}
String message = String.format("Avoid setting %1$s as values for `setTag`: " +
"Can lead to memory leaks in versions older than Android 4.0",
objectType);
context.report(ISSUE, call, context.getUastLocation(tagArgument), message);
}
}