| /* |
| * Copyright (C) 2018 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.tools.lint.client.api.UElementHandler |
| import com.android.tools.lint.detector.api.Category |
| import com.android.tools.lint.detector.api.ConstantEvaluator |
| import com.android.tools.lint.detector.api.Detector |
| import com.android.tools.lint.detector.api.Implementation |
| import com.android.tools.lint.detector.api.Issue |
| import com.android.tools.lint.detector.api.JavaContext |
| import com.android.tools.lint.detector.api.Scope |
| import com.android.tools.lint.detector.api.Severity |
| import com.android.tools.lint.detector.api.SourceCodeScanner |
| import com.android.tools.lint.detector.api.UastLintUtils |
| import com.android.tools.lint.detector.api.isKotlin |
| import com.intellij.psi.PsiClass |
| import com.intellij.psi.PsiField |
| import com.intellij.psi.PsiMember |
| import com.intellij.psi.PsiMethod |
| import org.jetbrains.uast.UCallExpression |
| import org.jetbrains.uast.UElement |
| import org.jetbrains.uast.USimpleNameReferenceExpression |
| import org.jetbrains.uast.getContainingUClass |
| import org.jetbrains.uast.util.isArrayInitializer |
| import org.jetbrains.uast.util.isNewArray |
| |
| /** |
| * Detector warning about private inner classes and constructors |
| * which require a synthetic accessor to be generated, thereby |
| * unnecessarily increasing overhead (methods, extra dispatch). |
| * Relevant only in large projects and especially libraries. |
| */ |
| class SyntheticAccessorDetector : Detector(), SourceCodeScanner { |
| companion object { |
| private val IMPLEMENTATION = Implementation( |
| SyntheticAccessorDetector::class.java, |
| Scope.JAVA_FILE_SCOPE |
| ) |
| |
| /** The main issue discovered by this detector */ |
| @JvmField |
| val ISSUE = Issue.create( |
| id = "SyntheticAccessor", |
| briefDescription = "Synthetic Accessor", |
| explanation = """ |
| A private inner class which is accessed from the outer class will force \ |
| the compiler to insert a synthetic accessor; this means that you are \ |
| causing extra overhead. This is not important in small projects, but is \ |
| important for large apps running up against the 64K method handle limit, \ |
| and especially for **libraries** where you want to make sure your library \ |
| is as small as possible for the cases where your library is used in an \ |
| app running up against the 64K limit. |
| """, |
| moreInfo = null, |
| category = Category.PERFORMANCE, |
| priority = 2, |
| severity = Severity.WARNING, |
| androidSpecific = true, |
| enabledByDefault = false, |
| implementation = IMPLEMENTATION |
| ) |
| |
| // A similar inspection is available in IntelliJ, using several different id's. |
| // Create a couple of internal issues with the same id's such that we can check |
| // for suppress directives for those other aliases. |
| |
| @Suppress("ObjectPropertyName") // underscore prefix required by testing infra |
| val _ALIAS_1 = Issue.create( |
| "SyntheticAccessorCall", |
| "?", |
| "?", |
| Category.LINT, |
| 1, |
| Severity.WARNING, |
| IMPLEMENTATION |
| ) |
| |
| @Suppress("ObjectPropertyName") // underscore prefix required by testing infra |
| val _ALIAS_2 = Issue.create( |
| "PrivateMemberAccessBetweenOuterAndInnerClass", |
| "?", |
| "?", |
| Category.LINT, |
| 1, |
| Severity.WARNING, |
| IMPLEMENTATION |
| ) |
| } |
| |
| override fun getApplicableUastTypes(): List<Class<out UElement>>? = |
| listOf(UCallExpression::class.java, USimpleNameReferenceExpression::class.java) |
| |
| override fun createUastHandler(context: JavaContext): UElementHandler? { |
| return object : UElementHandler() { |
| override fun visitCallExpression(node: UCallExpression) { |
| if (node.isNewArray() || node.isArrayInitializer()) { |
| return |
| } |
| val containingClass = node.getContainingUClass() ?: return |
| |
| val method = node.resolve() |
| if (method == null) { |
| // default constructor |
| val classRef = node.classReference ?: return |
| val target = classRef.resolve() as? PsiClass ?: return |
| if (!context.evaluator.isPrivate(target)) { |
| return |
| } |
| if (target.isEquivalentTo(containingClass)) { |
| return |
| } |
| |
| if (!isSameCompilationUnit(target, node)) { |
| return |
| } |
| |
| reportError(context, node, target, target) |
| } else { |
| if (!context.evaluator.isPrivate(method)) { |
| return |
| } |
| |
| val aClass = method.containingClass ?: return |
| if (aClass == containingClass.psi) { |
| return |
| } |
| |
| if (!isSameCompilationUnit(aClass, node)) { |
| return |
| } |
| |
| val from = node.getContainingUClass() |
| if (from != null && from.name == "Companion") { |
| // TODO: Companion objects can be named with a different name; |
| // we need be able to look this up in UAST |
| // Another way to do it is |
| // from.psi.modifierList.text.contains("companion") |
| return |
| } |
| |
| // Mention it's an implicit constructor here? |
| reportError(context, node, method, aClass) |
| } |
| } |
| |
| private fun isSameCompilationUnit(aClass: PsiClass, node: UElement): Boolean { |
| val file1 = UastLintUtils.getContainingFile(aClass) |
| val file2 = UastLintUtils.getContainingFile(node.sourcePsi) |
| return file1 == file2 |
| } |
| |
| override fun visitSimpleNameReferenceExpression(node: USimpleNameReferenceExpression) { |
| val resolved = node.resolve() ?: return |
| |
| if (!(resolved is PsiMethod || resolved is PsiField)) { |
| return |
| } |
| val member = resolved as PsiMember |
| if (!context.evaluator.isPrivate(member)) { |
| return |
| } |
| val constant = ConstantEvaluator.evaluate(context, node) |
| if (constant != null) { |
| return // constant expression: inlined by javac or kotlinc |
| } |
| |
| val containingClass = node.getContainingUClass() ?: return |
| val memberClass = member.containingClass |
| if (memberClass == null || memberClass == containingClass.psi) { |
| return |
| } |
| |
| if (!isSameCompilationUnit(memberClass, node)) { |
| return |
| } |
| |
| reportError(context, node, member, memberClass) |
| } |
| } |
| } |
| |
| private fun reportError( |
| context: JavaContext, |
| node: UElement, |
| member: PsiMember, |
| target: PsiClass |
| ) { |
| val driver = context.driver |
| if (driver.isSuppressed(context, _ALIAS_1, node) || |
| driver.isSuppressed(context, _ALIAS_2, node) |
| ) { |
| return |
| } |
| val location = |
| if (node is UCallExpression) { |
| context.getCallLocation(node, true, false) |
| } else { |
| context.getLocation(node) |
| } |
| |
| val isKotlin = isKotlin(member) |
| val name = if (isKotlin) "Make internal" else "Make package protected" |
| val fix = fix().replace() |
| .name(name) |
| .sharedName(name) |
| .range(context.getLocation(member)) |
| .text("private ") |
| .with(if (isKotlin) "internal " else "") |
| .autoFix() |
| .build() |
| |
| val memberType = if (member is PsiField) { |
| "field `${member.name}`" |
| } else if (member is PsiMethod) { |
| if (member.isConstructor) { |
| if (context.evaluator.isStatic(member)) { |
| return |
| } |
| if (isKotlin(member)) { |
| // Sealed class? This will create a private constructor we can't delete |
| if (context.evaluator.isSealed(member)) { |
| return |
| } |
| if (context.evaluator.isSealed(target)) { |
| return |
| } |
| } |
| "constructor" |
| } else { |
| "method `${member.name}`" |
| } |
| } else { |
| "member" |
| } |
| val message = |
| "Access to `private` $memberType of class `${target.name}` requires synthetic accessor" |
| context.report(ISSUE, node, location, message, fix) |
| } |
| } |
