com.android.tools.lint.client.api.AsmVisitor Maven / Gradle / Ivy
/*
* 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.lint.client.api;
import com.android.annotations.NonNull;
import com.android.tools.lint.detector.api.ClassContext;
import com.android.tools.lint.detector.api.Detector;
import com.android.tools.lint.detector.api.Detector.ClassScanner;
import com.google.common.annotations.Beta;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import org.objectweb.asm.tree.AbstractInsnNode;
import org.objectweb.asm.tree.ClassNode;
import org.objectweb.asm.tree.InsnList;
import org.objectweb.asm.tree.MethodInsnNode;
import org.objectweb.asm.tree.MethodNode;
/**
* Specialized visitor for running detectors on a class object model.
*
* It operates in two phases:
*
* - First, it computes a set of maps where it generates a map from each
* significant method name to a list of detectors to consult for that method
* name. The set of method names that a detector is interested in is provided
* by the detectors themselves.
*
- Second, it iterates over the DOM a single time. For each method call it finds,
* it dispatches to any check that has registered interest in that method name.
*
- Finally, it runs a full check on those class scanners that do not register
* specific method names to be checked. This is intended for those detectors
* that do custom work, not related specifically to method calls.
*
* It also notifies all the detectors before and after the document is processed
* such that they can do pre- and post-processing.
*
* NOTE: This is not a public or final API; if you rely on this be prepared
* to adjust your code for the next tools release.
*/
@Beta
class AsmVisitor {
/**
* Number of distinct node types specified in {@link AbstractInsnNode}. Sadly
* there isn't a max-constant there, so update this along with ASM library
* updates.
*/
private static final int TYPE_COUNT = AbstractInsnNode.LINE + 1;
private final Map> methodNameToChecks =
new HashMap<>();
private final Map> methodOwnerToChecks =
new HashMap<>();
private final List fullClassChecks = new ArrayList<>();
private final List allDetectors;
private List[] nodeTypeDetectors;
// Really want this:
// & Detector.ClassScanner> ClassVisitor(T xmlDetectors) {
// but it makes client code tricky and ugly.
@SuppressWarnings("unchecked")
AsmVisitor(@NonNull LintClient client, @NonNull List classDetectors) {
allDetectors = classDetectors;
// TODO: Check appliesTo() for files, and find a quick way to enable/disable
// rules when running through a full project!
for (Detector detector : classDetectors) {
Detector.ClassScanner scanner = (Detector.ClassScanner) detector;
boolean checkFullClass = true;
Collection names = scanner.getApplicableCallNames();
if (names != null) {
checkFullClass = false;
for (String element : names) {
List list = methodNameToChecks.get(element);
if (list == null) {
list = new ArrayList<>();
methodNameToChecks.put(element, list);
}
list.add(scanner);
}
}
Collection owners = scanner.getApplicableCallOwners();
if (owners != null) {
checkFullClass = false;
for (String element : owners) {
List list = methodOwnerToChecks.get(element);
if (list == null) {
list = new ArrayList<>();
methodOwnerToChecks.put(element, list);
}
list.add(scanner);
}
}
int[] types = scanner.getApplicableAsmNodeTypes();
if (types != null) {
checkFullClass = false;
for (int type : types) {
if (type < 0 || type >= TYPE_COUNT) {
// Can't support this node type: looks like ASM wasn't updated correctly.
client.log(null, "Out of range node type %1$d from detector %2$s",
type, scanner);
continue;
}
if (nodeTypeDetectors == null) {
nodeTypeDetectors = new List[TYPE_COUNT];
}
List checks = nodeTypeDetectors[type];
if (checks == null) {
checks = new ArrayList<>();
nodeTypeDetectors[type] = checks;
}
checks.add(scanner);
}
}
if (checkFullClass) {
fullClassChecks.add(detector);
}
}
}
@SuppressWarnings("rawtypes") // ASM API uses raw types
void runClassDetectors(ClassContext context) {
ClassNode classNode = context.getClassNode();
for (Detector detector : allDetectors) {
detector.beforeCheckFile(context);
}
for (Detector detector : fullClassChecks) {
Detector.ClassScanner scanner = (Detector.ClassScanner) detector;
scanner.checkClass(context, classNode);
detector.afterCheckFile(context);
}
if (!methodNameToChecks.isEmpty() || !methodOwnerToChecks.isEmpty() ||
nodeTypeDetectors != null && nodeTypeDetectors.length > 0) {
List methodList = classNode.methods;
for (Object m : methodList) {
MethodNode method = (MethodNode) m;
InsnList nodes = method.instructions;
for (int i = 0, n = nodes.size(); i < n; i++) {
AbstractInsnNode instruction = nodes.get(i);
int type = instruction.getType();
if (type == AbstractInsnNode.METHOD_INSN) {
MethodInsnNode call = (MethodInsnNode) instruction;
String owner = call.owner;
List scanners = methodOwnerToChecks.get(owner);
if (scanners != null) {
for (ClassScanner scanner : scanners) {
scanner.checkCall(context, classNode, method, call);
}
}
String name = call.name;
scanners = methodNameToChecks.get(name);
if (scanners != null) {
for (ClassScanner scanner : scanners) {
scanner.checkCall(context, classNode, method, call);
}
}
}
if (nodeTypeDetectors != null && type < nodeTypeDetectors.length) {
List scanners = nodeTypeDetectors[type];
if (scanners != null) {
for (ClassScanner scanner : scanners) {
scanner.checkInstruction(context, classNode, method, instruction);
}
}
}
}
}
}
for (Detector detector : allDetectors) {
detector.afterCheckFile(context);
}
}
}