| /* |
| * Copyright (C) 2014 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.annotations.Nullable; |
| import com.android.tools.lint.client.api.JavaParser.ResolvedMethod; |
| import com.android.tools.lint.client.api.JavaParser.TypeDescriptor; |
| import com.android.tools.lint.detector.api.Category; |
| import com.android.tools.lint.detector.api.Detector; |
| import com.android.tools.lint.detector.api.Detector.JavaScanner; |
| 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.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 java.util.Collections; |
| import java.util.List; |
| |
| import lombok.ast.AstVisitor; |
| import lombok.ast.ConstructorInvocation; |
| |
| /** |
| * Checks for errors related to Date Formats |
| */ |
| public class DateFormatDetector extends Detector implements JavaScanner { |
| |
| private static final Implementation IMPLEMENTATION = new Implementation( |
| DateFormatDetector.class, |
| Scope.JAVA_FILE_SCOPE); |
| |
| /** Constructing SimpleDateFormat without an explicit locale */ |
| public static final Issue DATE_FORMAT = Issue.create( |
| "SimpleDateFormat", //$NON-NLS-1$ |
| "Implied locale in date format", |
| |
| "Almost all callers should use `getDateInstance()`, `getDateTimeInstance()`, or " + |
| "`getTimeInstance()` to get a ready-made instance of SimpleDateFormat suitable " + |
| "for the user's locale. The main reason you'd create an instance this class " + |
| "directly is because you need to format/parse a specific machine-readable format, " + |
| "in which case you almost certainly want to explicitly ask for US to ensure that " + |
| "you get ASCII digits (rather than, say, Arabic digits).\n" + |
| "\n" + |
| "Therefore, you should either use the form of the SimpleDateFormat constructor " + |
| "where you pass in an explicit locale, such as Locale.US, or use one of the " + |
| "get instance methods, or suppress this error if really know what you are doing.", |
| |
| Category.CORRECTNESS, |
| 6, |
| Severity.WARNING, |
| IMPLEMENTATION) |
| .addMoreInfo( |
| "http://developer.android.com/reference/java/text/SimpleDateFormat.html");//$NON-NLS-1$ |
| |
| public static final String LOCALE_CLS = "java.util.Locale"; //$NON-NLS-1$ |
| public static final String SIMPLE_DATE_FORMAT_CLS = "java.text.SimpleDateFormat"; //$NON-NLS-1$ |
| |
| /** Constructs a new {@link DateFormatDetector} */ |
| public DateFormatDetector() { |
| } |
| |
| @NonNull |
| @Override |
| public Speed getSpeed() { |
| return Speed.FAST; |
| } |
| |
| // ---- Implements JavaScanner ---- |
| |
| @Nullable |
| @Override |
| public List<String> getApplicableConstructorTypes() { |
| return Collections.singletonList(SIMPLE_DATE_FORMAT_CLS); |
| } |
| |
| @Override |
| public void visitConstructor(@NonNull JavaContext context, @Nullable AstVisitor visitor, |
| @NonNull ConstructorInvocation node, @NonNull ResolvedMethod constructor) { |
| if (!specifiesLocale(constructor)) { |
| Location location = context.getLocation(node); |
| String message = |
| "To get local formatting use `getDateInstance()`, `getDateTimeInstance()`, " + |
| "or `getTimeInstance()`, or use `new SimpleDateFormat(String template, " + |
| "Locale locale)` with for example `Locale.US` for ASCII dates."; |
| context.report(DATE_FORMAT, node, location, message); |
| } |
| } |
| |
| private static boolean specifiesLocale(@NonNull ResolvedMethod method) { |
| for (int i = 0, n = method.getArgumentCount(); i < n; i++) { |
| TypeDescriptor argumentType = method.getArgumentType(i); |
| if (argumentType.matchesSignature(LOCALE_CLS)) { |
| return true; |
| } |
| } |
| return false; |
| } |
| } |