1 /* 2 * Copyright (c) 2000, 2014, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 27 package javax.management.openmbean; 28 29 30 // java import 31 // 32 import java.util.Set; 33 import java.util.TreeMap; 34 import java.util.Collections; 35 import java.util.Iterator; 36 37 // jmx import 38 // 39 40 41 /** 42 * The <code>CompositeType</code> class is the <i>open type</i> class 43 * whose instances describe the types of {@link CompositeData CompositeData} values. 44 * 45 * 46 * @since 1.5 47 */ 48 public class CompositeType extends OpenType<CompositeData> { 49 50 /* Serial version */ 51 static final long serialVersionUID = -5366242454346948798L; 52 53 /** 54 * @serial Sorted mapping of the item names to their descriptions 55 */ 56 private TreeMap<String,String> nameToDescription; 57 58 /** 59 * @serial Sorted mapping of the item names to their open types 60 */ 61 private TreeMap<String,OpenType<?>> nameToType; 62 63 /* As this instance is immutable, following three values need only 64 * be calculated once. */ 65 private transient Integer myHashCode = null; 66 private transient String myToString = null; 67 private transient Set<String> myNamesSet = null; 68 69 70 /* *** Constructor *** */ 71 72 /** 73 * Constructs a <code>CompositeType</code> instance, checking for the validity of the given parameters. 74 * The validity constraints are described below for each parameter. 75 * <p> 76 * Note that the contents of the three array parameters 77 * <var>itemNames</var>, <var>itemDescriptions</var> and <var>itemTypes</var> 78 * are internally copied so that any subsequent modification of these arrays by the caller of this constructor 79 * has no impact on the constructed <code>CompositeType</code> instance. 80 * <p> 81 * The Java class name of composite data values this composite type represents 82 * (ie the class name returned by the {@link OpenType#getClassName() getClassName} method) 83 * is set to the string value returned by <code>CompositeData.class.getName()</code>. 84 * 85 * @param typeName The name given to the composite type this instance represents; cannot be a null or empty string. 86 * 87 * @param description The human readable description of the composite type this instance represents; 88 * cannot be a null or empty string. 89 * 90 * @param itemNames The names of the items contained in the 91 * composite data values described by this <code>CompositeType</code> instance; 92 * cannot be null and should contain at least one element; no element can be a null or empty string. 93 * Note that the order in which the item names are given is not important to differentiate a 94 * <code>CompositeType</code> instance from another; 95 * the item names are internally stored sorted in ascending alphanumeric order. 96 * 97 * @param itemDescriptions The descriptions, in the same order as <var>itemNames</var>, of the items contained in the 98 * composite data values described by this <code>CompositeType</code> instance; 99 * should be of the same size as <var>itemNames</var>; 100 * no element can be null or an empty string. 101 * 102 * @param itemTypes The open type instances, in the same order as <var>itemNames</var>, describing the items contained 103 * in the composite data values described by this <code>CompositeType</code> instance; 104 * should be of the same size as <var>itemNames</var>; 105 * no element can be null. 106 * 107 * @throws IllegalArgumentException If <var>typeName</var> or <var>description</var> is a null or empty string, 108 * or <var>itemNames</var> or <var>itemDescriptions</var> or <var>itemTypes</var> is null, 109 * or any element of <var>itemNames</var> or <var>itemDescriptions</var> 110 * is a null or empty string, 111 * or any element of <var>itemTypes</var> is null, 112 * or <var>itemNames</var> or <var>itemDescriptions</var> or <var>itemTypes</var> 113 * are not of the same size. 114 * 115 * @throws OpenDataException If <var>itemNames</var> contains duplicate item names 116 * (case sensitive, but leading and trailing whitespaces removed). 117 */ 118 public CompositeType(String typeName, 119 String description, 120 String[] itemNames, 121 String[] itemDescriptions, 122 OpenType<?>[] itemTypes) throws OpenDataException { 123 124 // Check and construct state defined by parent 125 // 126 super(CompositeData.class.getName(), typeName, description, false); 127 128 // Check the 3 arrays are not null or empty (ie length==0) and that there is no null element or empty string in them 129 // 130 checkForNullElement(itemNames, "itemNames"); 131 checkForNullElement(itemDescriptions, "itemDescriptions"); 132 checkForNullElement(itemTypes, "itemTypes"); 133 checkForEmptyString(itemNames, "itemNames"); 134 checkForEmptyString(itemDescriptions, "itemDescriptions"); 135 136 // Check the sizes of the 3 arrays are the same 137 // 138 if ( (itemNames.length != itemDescriptions.length) || (itemNames.length != itemTypes.length) ) { 139 throw new IllegalArgumentException("Array arguments itemNames[], itemDescriptions[] and itemTypes[] "+ 140 "should be of same length (got "+ itemNames.length +", "+ 141 itemDescriptions.length +" and "+ itemTypes.length +")."); 142 } 143 144 // Initialize internal "names to descriptions" and "names to types" sorted maps, 145 // and, by doing so, check there are no duplicate item names 146 // 147 nameToDescription = new TreeMap<String,String>(); 148 nameToType = new TreeMap<String,OpenType<?>>(); 149 String key; 150 for (int i=0; i<itemNames.length; i++) { 151 key = itemNames[i].trim(); 152 if (nameToDescription.containsKey(key)) { 153 throw new OpenDataException("Argument's element itemNames["+ i +"]=\""+ itemNames[i] + 154 "\" duplicates a previous item names."); 155 } 156 nameToDescription.put(key, itemDescriptions[i].trim()); 157 nameToType.put(key, itemTypes[i]); 158 } 159 } 160 161 private static void checkForNullElement(Object[] arg, String argName) { 162 if ( (arg == null) || (arg.length == 0) ) { 163 throw new IllegalArgumentException("Argument "+ argName +"[] cannot be null or empty."); 164 } 165 for (int i=0; i<arg.length; i++) { 166 if (arg[i] == null) { 167 throw new IllegalArgumentException("Argument's element "+ argName +"["+ i +"] cannot be null."); 168 } 169 } 170 } 171 172 private static void checkForEmptyString(String[] arg, String argName) { 173 for (int i=0; i<arg.length; i++) { 174 if (arg[i].trim().equals("")) { 175 throw new IllegalArgumentException("Argument's element "+ argName +"["+ i +"] cannot be an empty string."); 176 } 177 } 178 } 179 180 /* *** Composite type specific information methods *** */ 181 182 /** 183 * Returns <code>true</code> if this <code>CompositeType</code> instance defines an item 184 * whose name is <var>itemName</var>. 185 * 186 * @param itemName the name of the item. 187 * 188 * @return true if an item of this name is present. 189 */ 190 public boolean containsKey(String itemName) { 191 192 if (itemName == null) { 193 return false; 194 } 195 return nameToDescription.containsKey(itemName); 196 } 197 198 /** 199 * Returns the description of the item whose name is <var>itemName</var>, 200 * or <code>null</code> if this <code>CompositeType</code> instance does not define any item 201 * whose name is <var>itemName</var>. 202 * 203 * @param itemName the name of the item. 204 * 205 * @return the description. 206 */ 207 public String getDescription(String itemName) { 208 209 if (itemName == null) { 210 return null; 211 } 212 return nameToDescription.get(itemName); 213 } 214 215 /** 216 * Returns the <i>open type</i> of the item whose name is <var>itemName</var>, 217 * or <code>null</code> if this <code>CompositeType</code> instance does not define any item 218 * whose name is <var>itemName</var>. 219 * 220 * @param itemName the name of the time. 221 * 222 * @return the type. 223 */ 224 public OpenType<?> getType(String itemName) { 225 226 if (itemName == null) { 227 return null; 228 } 229 return (OpenType<?>) nameToType.get(itemName); 230 } 231 232 /** 233 * Returns an unmodifiable Set view of all the item names defined by this <code>CompositeType</code> instance. 234 * The set's iterator will return the item names in ascending order. 235 * 236 * @return a {@link Set} of {@link String}. 237 */ 238 public Set<String> keySet() { 239 240 // Initializes myNamesSet on first call 241 if (myNamesSet == null) { 242 myNamesSet = Collections.unmodifiableSet(nameToDescription.keySet()); 243 } 244 245 return myNamesSet; // always return the same value 246 } 247 248 249 /** 250 * Tests whether <var>obj</var> is a value which could be 251 * described by this <code>CompositeType</code> instance. 252 * 253 * <p>If <var>obj</var> is null or is not an instance of 254 * <code>javax.management.openmbean.CompositeData</code>, 255 * <code>isValue</code> returns <code>false</code>.</p> 256 * 257 * <p>If <var>obj</var> is an instance of 258 * <code>javax.management.openmbean.CompositeData</code>, then let 259 * {@code ct} be its {@code CompositeType} as returned by {@link 260 * CompositeData#getCompositeType()}. The result is true if 261 * {@code this} is <em>assignable from</em> {@code ct}. This 262 * means that:</p> 263 * 264 * <ul> 265 * <li>{@link #getTypeName() this.getTypeName()} equals 266 * {@code ct.getTypeName()}, and 267 * <li>there are no item names present in {@code this} that are 268 * not also present in {@code ct}, and 269 * <li>for every item in {@code this}, its type is assignable from 270 * the type of the corresponding item in {@code ct}. 271 * </ul> 272 * 273 * <p>A {@code TabularType} is assignable from another {@code 274 * TabularType} if they have the same {@linkplain 275 * TabularType#getTypeName() typeName} and {@linkplain 276 * TabularType#getIndexNames() index name list}, and the 277 * {@linkplain TabularType#getRowType() row type} of the first is 278 * assignable from the row type of the second. 279 * 280 * <p>An {@code ArrayType} is assignable from another {@code 281 * ArrayType} if they have the same {@linkplain 282 * ArrayType#getDimension() dimension}; and both are {@linkplain 283 * ArrayType#isPrimitiveArray() primitive arrays} or neither is; 284 * and the {@linkplain ArrayType#getElementOpenType() element 285 * type} of the first is assignable from the element type of the 286 * second. 287 * 288 * <p>In every other case, an {@code OpenType} is assignable from 289 * another {@code OpenType} only if they are equal.</p> 290 * 291 * <p>These rules mean that extra items can be added to a {@code 292 * CompositeData} without making it invalid for a {@code CompositeType} 293 * that does not have those items.</p> 294 * 295 * @param obj the value whose open type is to be tested for compatibility 296 * with this <code>CompositeType</code> instance. 297 * 298 * @return <code>true</code> if <var>obj</var> is a value for this 299 * composite type, <code>false</code> otherwise. 300 */ 301 public boolean isValue(Object obj) { 302 303 // if obj is null or not CompositeData, return false 304 // 305 if (!(obj instanceof CompositeData)) { 306 return false; 307 } 308 309 // if obj is not a CompositeData, return false 310 // 311 CompositeData value = (CompositeData) obj; 312 313 // test value's CompositeType is assignable to this CompositeType instance 314 // 315 CompositeType valueType = value.getCompositeType(); 316 return this.isAssignableFrom(valueType); 317 } 318 319 /** 320 * Tests whether values of the given type can be assigned to this 321 * open type. The result is true if the given type is also a 322 * CompositeType with the same name ({@link #getTypeName()}), and 323 * every item in this type is also present in the given type with 324 * the same name and assignable type. There can be additional 325 * items in the given type, which are ignored. 326 * 327 * @param ot the type to be tested. 328 * 329 * @return true if {@code ot} is assignable to this open type. 330 */ 331 @Override 332 boolean isAssignableFrom(OpenType<?> ot) { 333 if (!(ot instanceof CompositeType)) 334 return false; 335 CompositeType ct = (CompositeType) ot; 336 if (!ct.getTypeName().equals(getTypeName())) 337 return false; 338 for (String key : keySet()) { 339 OpenType<?> otItemType = ct.getType(key); 340 OpenType<?> thisItemType = getType(key); 341 if (otItemType == null || 342 !thisItemType.isAssignableFrom(otItemType)) 343 return false; 344 } 345 return true; 346 } 347 348 349 /* *** Methods overriden from class Object *** */ 350 351 /** 352 * Compares the specified <code>obj</code> parameter with this <code>CompositeType</code> instance for equality. 353 * <p> 354 * Two <code>CompositeType</code> instances are equal if and only if all of the following statements are true: 355 * <ul> 356 * <li>their type names are equal</li> 357 * <li>their items' names and types are equal</li> 358 * </ul> 359 * 360 * @param obj the object to be compared for equality with this <code>CompositeType</code> instance; 361 * if <var>obj</var> is <code>null</code>, <code>equals</code> returns <code>false</code>. 362 * 363 * @return <code>true</code> if the specified object is equal to this <code>CompositeType</code> instance. 364 */ 365 public boolean equals(Object obj) { 366 367 // if obj is null, return false 368 // 369 if (obj == null) { 370 return false; 371 } 372 373 // if obj is not a CompositeType, return false 374 // 375 CompositeType other; 376 try { 377 other = (CompositeType) obj; 378 } catch (ClassCastException e) { 379 return false; 380 } 381 382 // Now, really test for equality between this CompositeType instance and the other 383 // 384 385 // their names should be equal 386 if ( ! this.getTypeName().equals(other.getTypeName()) ) { 387 return false; 388 } 389 390 // their items names and types should be equal 391 if ( ! this.nameToType.equals(other.nameToType) ) { 392 return false; 393 } 394 395 // All tests for equality were successfull 396 // 397 return true; 398 } 399 400 /** 401 * Returns the hash code value for this <code>CompositeType</code> instance. 402 * <p> 403 * The hash code of a <code>CompositeType</code> instance is the sum of the hash codes 404 * of all elements of information used in <code>equals</code> comparisons 405 * (ie: name, items names, items types). 406 * This ensures that <code> t1.equals(t2) </code> implies that <code> t1.hashCode()==t2.hashCode() </code> 407 * for any two <code>CompositeType</code> instances <code>t1</code> and <code>t2</code>, 408 * as required by the general contract of the method 409 * {@link Object#hashCode() Object.hashCode()}. 410 * <p> 411 * As <code>CompositeType</code> instances are immutable, the hash code for this instance is calculated once, 412 * on the first call to <code>hashCode</code>, and then the same value is returned for subsequent calls. 413 * 414 * @return the hash code value for this <code>CompositeType</code> instance 415 */ 416 public int hashCode() { 417 418 // Calculate the hash code value if it has not yet been done (ie 1st call to hashCode()) 419 // 420 if (myHashCode == null) { 421 int value = 0; 422 value += this.getTypeName().hashCode(); 423 for (String key : nameToDescription.keySet()) { 424 value += key.hashCode(); 425 value += this.nameToType.get(key).hashCode(); 426 } 427 myHashCode = Integer.valueOf(value); 428 } 429 430 // return always the same hash code for this instance (immutable) 431 // 432 return myHashCode.intValue(); 433 } 434 435 /** 436 * Returns a string representation of this <code>CompositeType</code> instance. 437 * <p> 438 * The string representation consists of 439 * the name of this class (ie <code>javax.management.openmbean.CompositeType</code>), the type name for this instance, 440 * and the list of the items names and types string representation of this instance. 441 * <p> 442 * As <code>CompositeType</code> instances are immutable, the string representation for this instance is calculated once, 443 * on the first call to <code>toString</code>, and then the same value is returned for subsequent calls. 444 * 445 * @return a string representation of this <code>CompositeType</code> instance 446 */ 447 public String toString() { 448 449 // Calculate the string representation if it has not yet been done (ie 1st call to toString()) 450 // 451 if (myToString == null) { 452 final StringBuilder result = new StringBuilder(); 453 result.append(this.getClass().getName()); 454 result.append("(name="); 455 result.append(getTypeName()); 456 result.append(",items=("); 457 int i=0; 458 Iterator<String> k=nameToType.keySet().iterator(); 459 String key; 460 while (k.hasNext()) { 461 key = k.next(); 462 if (i > 0) result.append(","); 463 result.append("(itemName="); 464 result.append(key); 465 result.append(",itemType="); 466 result.append(nameToType.get(key)).append(')'); 467 i++; 468 } 469 result.append("))"); 470 myToString = result.toString(); 471 } 472 473 // return always the same string representation for this instance (immutable) 474 // 475 return myToString; 476 } 477 478 }