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-rw-r--r--lint/libs/lint_checks/src/com/android/tools/lint/checks/FieldGetterDetector.java265
1 files changed, 0 insertions, 265 deletions
diff --git a/lint/libs/lint_checks/src/com/android/tools/lint/checks/FieldGetterDetector.java b/lint/libs/lint_checks/src/com/android/tools/lint/checks/FieldGetterDetector.java
deleted file mode 100644
index a1fd9fa..0000000
--- a/lint/libs/lint_checks/src/com/android/tools/lint/checks/FieldGetterDetector.java
+++ /dev/null
@@ -1,265 +0,0 @@
-/*
- * Copyright (C) 2011 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.lint.checks;
-
-import com.android.annotations.NonNull;
-import com.android.tools.lint.detector.api.Category;
-import com.android.tools.lint.detector.api.ClassContext;
-import com.android.tools.lint.detector.api.Context;
-import com.android.tools.lint.detector.api.Detector;
-import com.android.tools.lint.detector.api.Issue;
-import com.android.tools.lint.detector.api.LintUtils;
-import com.android.tools.lint.detector.api.Location;
-import com.android.tools.lint.detector.api.Scope;
-import com.android.tools.lint.detector.api.Severity;
-import com.android.tools.lint.detector.api.Speed;
-import com.google.common.collect.Maps;
-
-import org.objectweb.asm.Opcodes;
-import org.objectweb.asm.tree.AbstractInsnNode;
-import org.objectweb.asm.tree.ClassNode;
-import org.objectweb.asm.tree.FieldInsnNode;
-import org.objectweb.asm.tree.InsnList;
-import org.objectweb.asm.tree.MethodInsnNode;
-import org.objectweb.asm.tree.MethodNode;
-import org.objectweb.asm.tree.VarInsnNode;
-
-import java.util.ArrayList;
-import java.util.HashSet;
-import java.util.List;
-import java.util.Map;
-import java.util.Set;
-
-/**
- * Looks for getter calls within the same class that could be replaced by
- * direct field references instead.
- */
-public class FieldGetterDetector extends Detector implements Detector.ClassScanner {
- /** The main issue discovered by this detector */
- public static final Issue ISSUE = Issue.create(
- "FieldGetter", //$NON-NLS-1$
- "Suggests replacing uses of getters with direct field access within a class",
-
- "Accessing a field within the class that defines a getter for that field is " +
- "at least 3 times faster than calling the getter. For simple getters that do " +
- "nothing other than return the field, you might want to just reference the " +
- "local field directly instead.\n" +
- "\n" +
- "NOTE: As of Android 2.3 (Gingerbread), this optimization is performed " +
- "automatically by Dalvik, so there is no need to change your code; this is " +
- "only relevant if you are targeting older versions of Android.",
-
- Category.PERFORMANCE,
- 4,
- Severity.WARNING,
- FieldGetterDetector.class,
- Scope.CLASS_FILE_SCOPE).
- // This is a micro-optimization: not enabled by default
- setEnabledByDefault(false).setMoreInfo(
- "http://developer.android.com/guide/practices/design/performance.html#internal_get_set"); //$NON-NLS-1$
- private ArrayList<Entry> mPendingCalls;
-
- /** Constructs a new {@link FieldGetterDetector} check */
- public FieldGetterDetector() {
- }
-
- @Override
- public @NonNull Speed getSpeed() {
- return Speed.FAST;
- }
-
- // ---- Implements ClassScanner ----
-
- @Override
- public int[] getApplicableAsmNodeTypes() {
- return new int[] { AbstractInsnNode.METHOD_INSN };
- }
-
- @Override
- public void checkInstruction(@NonNull ClassContext context, @NonNull ClassNode classNode,
- @NonNull MethodNode method, @NonNull AbstractInsnNode instruction) {
- // As of Gingerbread/API 9, Dalvik performs this optimization automatically
- if (context.getProject().getMinSdk() >= 9) {
- return;
- }
-
- if ((method.access & Opcodes.ACC_STATIC) != 0) {
- // Not an instance method
- return;
- }
-
- if (instruction.getOpcode() != Opcodes.INVOKEVIRTUAL) {
- return;
- }
-
- MethodInsnNode node = (MethodInsnNode) instruction;
- String name = node.name;
- String owner = node.owner;
-
- AbstractInsnNode prev = LintUtils.getPrevInstruction(instruction);
- if (prev == null || prev.getOpcode() != Opcodes.ALOAD) {
- return;
- }
- VarInsnNode prevVar = (VarInsnNode) prev;
- if (prevVar.var != 0) { // Not on "this", variable 0 in instance methods?
- return;
- }
-
- if (((name.startsWith("get") && name.length() > 3 //$NON-NLS-1$
- && Character.isUpperCase(name.charAt(3)))
- || (name.startsWith("is") && name.length() > 2 //$NON-NLS-1$
- && Character.isUpperCase(name.charAt(2))))
- && owner.equals(classNode.name)) {
- // Calling a potential getter method on self. We now need to
- // investigate the method body of the getter call and make sure
- // it's really a plain getter, not just a method which happens
- // to have a method name like a getter, or a method which not
- // only returns a field but possibly computes it or performs
- // other initialization or side effects. This is done in a
- // second pass over the bytecode, initiated by the finish()
- // method.
- if (mPendingCalls == null) {
- mPendingCalls = new ArrayList<Entry>();
- }
-
- mPendingCalls.add(new Entry(name, node, method));
- }
-
- super.checkInstruction(context, classNode, method, instruction);
- }
-
- @Override
- public void afterCheckFile(@NonNull Context c) {
- ClassContext context = (ClassContext) c;
-
- if (mPendingCalls != null) {
- Set<String> names = new HashSet<String>(mPendingCalls.size());
- for (Entry entry : mPendingCalls) {
- names.add(entry.name);
- }
-
- Map<String, String> getters = checkMethods(context.getClassNode(), names);
- if (getters.size() > 0) {
- for (String getter : getters.keySet()) {
- for (Entry entry : mPendingCalls) {
- String name = entry.name;
- // There can be more than one reference to the same name:
- // one for each call site
- if (name.equals(getter)) {
- Location location = context.getLocation(entry.call);
- String fieldName = getters.get(getter);
- if (fieldName == null) {
- fieldName = "";
- }
- context.report(ISSUE, entry.method, location, String.format(
- "Calling getter method %1$s() on self is " +
- "slower than field access (%2$s)", getter, fieldName), fieldName);
- }
- }
- }
- }
- }
-
- mPendingCalls = null;
- }
-
- // Holder class for getters to be checked
- private static class Entry {
- public final String name;
- public final MethodNode method;
- public final MethodInsnNode call;
-
- public Entry(String name, MethodInsnNode call, MethodNode method) {
- super();
- this.name = name;
- this.call = call;
- this.method = method;
- }
- }
-
- // Validate that these getter methods are really just simple field getters
- // like these int and STring getters:
- // public int getFoo();
- // Code:
- // 0: aload_0
- // 1: getfield #21; //Field mFoo:I
- // 4: ireturn
- //
- // public java.lang.String getBar();
- // Code:
- // 0: aload_0
- // 1: getfield #25; //Field mBar:Ljava/lang/String;
- // 4: areturn
- //
- // Returns a map of valid getters as keys, and if the field name is found, the field name
- // for each getter as its value.
- private static Map<String, String> checkMethods(ClassNode classNode, Set<String> names) {
- Map<String, String> validGetters = Maps.newHashMap();
- @SuppressWarnings("rawtypes")
- List methods = classNode.methods;
- String fieldName = null;
- checkMethod:
- for (Object methodObject : methods) {
- MethodNode method = (MethodNode) methodObject;
- if (names.contains(method.name)
- && method.desc.startsWith("()")) { //$NON-NLS-1$ // (): No arguments
- InsnList instructions = method.instructions;
- int mState = 1;
- for (AbstractInsnNode curr = instructions.getFirst();
- curr != null;
- curr = curr.getNext()) {
- switch (curr.getOpcode()) {
- case -1:
- // Skip label and line number nodes
- continue;
- case Opcodes.ALOAD:
- if (mState == 1) {
- fieldName = null;
- mState = 2;
- } else {
- continue checkMethod;
- }
- break;
- case Opcodes.GETFIELD:
- if (mState == 2) {
- FieldInsnNode field = (FieldInsnNode) curr;
- fieldName = field.name;
- mState = 3;
- } else {
- continue checkMethod;
- }
- break;
- case Opcodes.ARETURN:
- case Opcodes.FRETURN:
- case Opcodes.IRETURN:
- case Opcodes.DRETURN:
- case Opcodes.LRETURN:
- case Opcodes.RETURN:
- if (mState == 3) {
- validGetters.put(method.name, fieldName);
- }
- continue checkMethod;
- default:
- continue checkMethod;
- }
- }
- }
- }
-
- return validGetters;
- }
-}
generated by cgit v1.1 at 2024-06-08 07:20:34 +0000