1 /* 2 * Copyright (C) 2014 Google, Inc. 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 package dagger.internal.codegen.writer; 17 18 import com.google.common.base.Ascii; 19 import com.google.common.base.Joiner; 20 import com.google.common.base.Objects; 21 import com.google.common.base.Optional; 22 import com.google.common.base.Splitter; 23 import com.google.common.collect.ImmutableList; 24 import com.google.common.collect.ImmutableSet; 25 import com.google.common.collect.Sets; 26 import java.io.IOException; 27 import java.util.ArrayList; 28 import java.util.Collections; 29 import java.util.Iterator; 30 import java.util.List; 31 import java.util.Set; 32 import javax.lang.model.SourceVersion; 33 import javax.lang.model.element.Element; 34 import javax.lang.model.element.ElementKind; 35 import javax.lang.model.element.NestingKind; 36 import javax.lang.model.element.PackageElement; 37 import javax.lang.model.element.TypeElement; 38 39 import static com.google.common.base.Preconditions.checkArgument; 40 import static com.google.common.base.Preconditions.checkNotNull; 41 import static javax.lang.model.element.NestingKind.MEMBER; 42 import static javax.lang.model.element.NestingKind.TOP_LEVEL; 43 44 /** 45 * Represents a fully-qualified class name for {@link NestingKind#TOP_LEVEL} and 46 * {@link NestingKind#MEMBER} classes. 47 * 48 * @since 2.0 49 */ 50 public final class ClassName implements TypeName, Comparable<ClassName> { 51 private String fullyQualifiedName = null; 52 private final String packageName; 53 /* From top to bottom. E.g.: this field will contain ["A", "B"] for pgk.A.B.C */ 54 private final ImmutableList<String> enclosingSimpleNames; 55 private final String simpleName; 56 ClassName(String packageName, ImmutableList<String> enclosingSimpleNames, String simpleName)57 private ClassName(String packageName, ImmutableList<String> enclosingSimpleNames, 58 String simpleName) { 59 this.packageName = packageName; 60 this.enclosingSimpleNames = enclosingSimpleNames; 61 this.simpleName = simpleName; 62 } 63 packageName()64 public String packageName() { 65 return packageName; 66 } 67 enclosingSimpleNames()68 public ImmutableList<String> enclosingSimpleNames() { 69 return enclosingSimpleNames; 70 } 71 enclosingClassName()72 public Optional<ClassName> enclosingClassName() { 73 return enclosingSimpleNames.isEmpty() 74 ? Optional.<ClassName>absent() 75 : Optional.of(new ClassName(packageName, 76 enclosingSimpleNames.subList(0, enclosingSimpleNames.size() - 1), 77 enclosingSimpleNames.get(enclosingSimpleNames.size() - 1))); 78 } 79 simpleName()80 public String simpleName() { 81 return simpleName; 82 } 83 canonicalName()84 public String canonicalName() { 85 if (fullyQualifiedName == null) { 86 StringBuilder builder = new StringBuilder(packageName()); 87 if (builder.length() > 0) { 88 builder.append('.'); 89 } 90 for (String enclosingSimpleName : enclosingSimpleNames()) { 91 builder.append(enclosingSimpleName).append('.'); 92 } 93 fullyQualifiedName = builder.append(simpleName()).toString(); 94 } 95 return fullyQualifiedName; 96 } 97 98 /** 99 * Equivalent to {@link #classFileName(char) classFileName('$')} 100 */ classFileName()101 public String classFileName() { 102 return classFileName('$'); 103 } 104 105 /** 106 * Returns the class name (excluding package). 107 * 108 * <p>The returned value includes the names of its enclosing classes (if any) but not the package 109 * name. e.g. {@code fromClass(Map.Entry.class).classFileName('_')} will return {@code Map_Entry}. 110 */ classFileName(char separator)111 public String classFileName(char separator) { 112 StringBuilder builder = new StringBuilder(); 113 for (String enclosingSimpleName : enclosingSimpleNames) { 114 builder.append(enclosingSimpleName).append(separator); 115 } 116 return builder.append(simpleName()).toString(); 117 } 118 topLevelClassName()119 public ClassName topLevelClassName() { 120 Iterator<String> enclosingIterator = enclosingSimpleNames().iterator(); 121 return enclosingIterator.hasNext() 122 ? new ClassName(packageName(), ImmutableList.<String>of(), 123 enclosingIterator.next()) 124 : this; 125 } 126 nestedClassNamed(String memberClassName)127 public ClassName nestedClassNamed(String memberClassName) { 128 checkNotNull(memberClassName); 129 checkArgument(SourceVersion.isIdentifier(memberClassName)); 130 return new ClassName(packageName(), 131 new ImmutableList.Builder<String>() 132 .addAll(enclosingSimpleNames()) 133 .add(simpleName()) 134 .build(), 135 memberClassName); 136 } 137 peerNamed(String peerClassName)138 public ClassName peerNamed(String peerClassName) { 139 checkNotNull(peerClassName); 140 checkArgument(SourceVersion.isIdentifier(peerClassName)); 141 return new ClassName(packageName(), enclosingSimpleNames(), peerClassName); 142 } 143 144 /** 145 * Returns a parameterized type name with this as its raw type if {@code parameters} is not empty. 146 * If {@code parameters} is empty, returns this object. 147 */ withTypeParameters(List<? extends TypeName> parameters)148 public TypeName withTypeParameters(List<? extends TypeName> parameters) { 149 return parameters.isEmpty() ? this : ParameterizedTypeName.create(this, parameters); 150 } 151 152 private static final ImmutableSet<NestingKind> ACCEPTABLE_NESTING_KINDS = 153 Sets.immutableEnumSet(TOP_LEVEL, MEMBER); 154 fromTypeElement(TypeElement element)155 public static ClassName fromTypeElement(TypeElement element) { 156 checkNotNull(element); 157 checkArgument(ACCEPTABLE_NESTING_KINDS.contains(element.getNestingKind())); 158 String simpleName = element.getSimpleName().toString(); 159 List<String> enclosingNames = new ArrayList<String>(); 160 Element current = element.getEnclosingElement(); 161 while (current.getKind().isClass() || current.getKind().isInterface()) { 162 checkArgument(ACCEPTABLE_NESTING_KINDS.contains(element.getNestingKind())); 163 enclosingNames.add(current.getSimpleName().toString()); 164 current = current.getEnclosingElement(); 165 } 166 PackageElement packageElement = getPackage(current); 167 Collections.reverse(enclosingNames); 168 return new ClassName(packageElement.getQualifiedName().toString(), 169 ImmutableList.copyOf(enclosingNames), simpleName); 170 } 171 fromClass(Class<?> clazz)172 public static ClassName fromClass(Class<?> clazz) { 173 checkNotNull(clazz); 174 List<String> enclosingNames = new ArrayList<String>(); 175 Class<?> current = clazz.getEnclosingClass(); 176 while (current != null) { 177 enclosingNames.add(current.getSimpleName()); 178 current = current.getEnclosingClass(); 179 } 180 Collections.reverse(enclosingNames); 181 return create(clazz.getPackage().getName(), enclosingNames, clazz.getSimpleName()); 182 } 183 getPackage(Element type)184 private static PackageElement getPackage(Element type) { 185 while (type.getKind() != ElementKind.PACKAGE) { 186 type = type.getEnclosingElement(); 187 } 188 return (PackageElement) type; 189 } 190 191 /** 192 * Returns a new {@link ClassName} instance for the given fully-qualified class name string. This 193 * method assumes that the input is ASCII and follows typical Java style (lower-case package 194 * names, upper-camel-case class names) and may produce incorrect results or throw 195 * {@link IllegalArgumentException} otherwise. For that reason, {@link #fromClass(Class)} and 196 * {@link #fromClass(Class)} should be preferred as they can correctly create {@link ClassName} 197 * instances without such restrictions. 198 */ bestGuessFromString(String classNameString)199 public static ClassName bestGuessFromString(String classNameString) { 200 checkNotNull(classNameString); 201 List<String> parts = Splitter.on('.').splitToList(classNameString); 202 int firstClassPartIndex = -1; 203 for (int i = 0; i < parts.size(); i++) { 204 String part = parts.get(i); 205 checkArgument(SourceVersion.isIdentifier(part)); 206 char firstChar = part.charAt(0); 207 if (Ascii.isLowerCase(firstChar)) { 208 // looks like a package part 209 if (firstClassPartIndex >= 0) { 210 throw new IllegalArgumentException("couldn't make a guess for " + classNameString); 211 } 212 } else if (Ascii.isUpperCase(firstChar)) { 213 // looks like a class part 214 if (firstClassPartIndex < 0) { 215 firstClassPartIndex = i; 216 } 217 } else { 218 throw new IllegalArgumentException("couldn't make a guess for " + classNameString); 219 } 220 } 221 int lastIndex = parts.size() - 1; 222 return new ClassName( 223 Joiner.on('.').join(parts.subList(0, firstClassPartIndex)), 224 firstClassPartIndex == lastIndex 225 ? ImmutableList.<String>of() 226 : ImmutableList.copyOf(parts.subList(firstClassPartIndex, lastIndex)), 227 parts.get(lastIndex)); 228 } 229 create( String packageName, List<String> enclosingSimpleNames, String simpleName)230 public static ClassName create( 231 String packageName, List<String> enclosingSimpleNames, String simpleName) { 232 return new ClassName(packageName, ImmutableList.copyOf(enclosingSimpleNames), 233 simpleName); 234 } 235 create(String packageName, String simpleName)236 public static ClassName create(String packageName, String simpleName) { 237 return new ClassName(packageName, ImmutableList.<String>of(), simpleName); 238 } 239 240 @Override toString()241 public String toString() { 242 return canonicalName(); 243 } 244 245 @Override write(Appendable appendable, Context context)246 public Appendable write(Appendable appendable, Context context) throws IOException { 247 appendable.append(context.sourceReferenceForClassName(this)); 248 return appendable; 249 } 250 251 @Override equals(Object obj)252 public boolean equals(Object obj) { 253 if (obj == this) { 254 return true; 255 } else if (obj instanceof ClassName) { 256 ClassName that = (ClassName) obj; 257 return this.packageName.equals(that.packageName) 258 && this.enclosingSimpleNames.equals(that.enclosingSimpleNames) 259 && this.simpleName.equals(that.simpleName); 260 } else { 261 return false; 262 } 263 } 264 265 @Override hashCode()266 public int hashCode() { 267 return Objects.hashCode(packageName, enclosingSimpleNames, simpleName); 268 } 269 270 @Override compareTo(ClassName o)271 public int compareTo(ClassName o) { 272 return canonicalName().compareTo(o.canonicalName()); 273 } 274 275 @Override referencedClasses()276 public Set<ClassName> referencedClasses() { 277 return ImmutableSet.of(this); 278 } 279 } 280