ExprModel.java revision c96847768305d83c6bc4919432af9bd9bfe4c08e
1/* 2 * Copyright (C) 2015 The Android Open Source Project 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 17package android.databinding.tool.expr; 18 19import com.google.common.base.Preconditions; 20import com.google.common.base.Predicate; 21import com.google.common.collect.Iterables; 22import com.google.common.collect.Lists; 23 24import android.databinding.tool.reflection.ModelAnalyzer; 25import android.databinding.tool.util.L; 26import android.databinding.tool.writer.FlagSet; 27 28import java.util.ArrayList; 29import java.util.Arrays; 30import java.util.BitSet; 31import java.util.HashMap; 32import java.util.List; 33import java.util.Map; 34 35public class ExprModel { 36 37 Map<String, Expr> mExprMap = new HashMap<String, Expr>(); 38 39 List<Expr> mBindingExpressions = new ArrayList<Expr>(); 40 41 private int mInvalidateableFieldLimit = 0; 42 43 private int mRequirementIdCount = 0; 44 45 // each arg list receives a unique id even if it is the same arguments and method. 46 private int mArgListIdCounter = 0; 47 48 private static final String TRUE_KEY_SUFFIX = "== true"; 49 private static final String FALSE_KEY_SUFFIX = "== false"; 50 51 /** 52 * Any expression can be invalidated by invalidating this flag. 53 */ 54 private BitSet mInvalidateAnyFlags; 55 56 /** 57 * Used by code generation. Keeps the list of expressions that are waiting to be evaluated. 58 */ 59 private List<Expr> mPendingExpressions; 60 61 /** 62 * Used for converting flags into identifiers while debugging. 63 */ 64 private String[] mFlagMapping; 65 66 private BitSet mInvalidateableFlags; 67 private BitSet mConditionalFlags; 68 69 private int mFlagBucketCount;// how many buckets we use to identify flags 70 71 private List<Expr> mObservables; 72 73 private boolean mSealed = false; 74 75 private Map<String, String> mImports = new HashMap<String, String>(); 76 77 /** 78 * Adds the expression to the list of expressions and returns it. 79 * If it already exists, returns existing one. 80 * 81 * @param expr The new parsed expression 82 * @return The expression itself or another one if the same thing was parsed before 83 */ 84 public <T extends Expr> T register(T expr) { 85 Preconditions.checkState(!mSealed, "Cannot add expressions to a model after it is sealed"); 86 T existing = (T) mExprMap.get(expr.getUniqueKey()); 87 if (existing != null) { 88 Preconditions.checkState(expr.getParents().isEmpty(), 89 "If an expression already exists, it should've never been added to a parent," 90 + "if thats the case, somewhere we are creating an expression w/o" 91 + "calling expression model"); 92 // tell the expr that it is being swapped so that if it was added to some other expr 93 // as a parent, those can swap their references 94 expr.onSwappedWith(existing); 95 return existing; 96 } 97 mExprMap.put(expr.getUniqueKey(), expr); 98 expr.setModel(this); 99 return expr; 100 } 101 102 public void unregister(Expr expr) { 103 mExprMap.remove(expr.getUniqueKey()); 104 } 105 106 public Map<String, Expr> getExprMap() { 107 return mExprMap; 108 } 109 110 public int size() { 111 return mExprMap.size(); 112 } 113 114 public ComparisonExpr comparison(String op, Expr left, Expr right) { 115 return register(new ComparisonExpr(op, left, right)); 116 } 117 118 public InstanceOfExpr instanceOfOp(Expr expr, String type) { 119 return register(new InstanceOfExpr(expr, type)); 120 } 121 122 public FieldAccessExpr field(Expr parent, String name) { 123 return register(new FieldAccessExpr(parent, name)); 124 } 125 126 public FieldAccessExpr observableField(Expr parent, String name) { 127 return register(new FieldAccessExpr(parent, name, true)); 128 } 129 130 public SymbolExpr symbol(String text, Class type) { 131 return register(new SymbolExpr(text, type)); 132 } 133 134 public TernaryExpr ternary(Expr pred, Expr ifTrue, Expr ifFalse) { 135 return register(new TernaryExpr(pred, ifTrue, ifFalse)); 136 } 137 138 public IdentifierExpr identifier(String name) { 139 return register(new IdentifierExpr(name)); 140 } 141 142 public StaticIdentifierExpr staticIdentifier(String name) { 143 return register(new StaticIdentifierExpr(name)); 144 } 145 146 public MethodCallExpr methodCall(Expr target, String name, List<Expr> args) { 147 return register(new MethodCallExpr(target, name, args)); 148 } 149 150 public MathExpr math(Expr left, String op, Expr right) { 151 return register(new MathExpr(left, op, right)); 152 } 153 154 public TernaryExpr logical(Expr left, String op, Expr right) { 155 if ("&&".equals(op)) { 156 // left && right 157 // left ? right : false 158 return register(new TernaryExpr(left, right, symbol("false", boolean.class))); 159 } else { 160 // left || right 161 // left ? true : right 162 return register(new TernaryExpr(left, symbol("true", boolean.class), right)); 163 } 164 } 165 166 public BitShiftExpr bitshift(Expr left, String op, Expr right) { 167 return register(new BitShiftExpr(left, op, right)); 168 } 169 170 public UnaryExpr unary(String op, Expr expr) { 171 return register(new UnaryExpr(op, expr)); 172 } 173 174 public Expr group(Expr grouped) { 175 return register(new GroupExpr(grouped)); 176 } 177 178 public Expr resourceExpr(String packageName, String resourceType, String resourceName, 179 List<Expr> args) { 180 return register(new ResourceExpr(packageName, resourceType, resourceName, args)); 181 } 182 183 public Expr bracketExpr(Expr variableExpr, Expr argExpr) { 184 return register(new BracketExpr(variableExpr, argExpr)); 185 } 186 187 public Expr castExpr(String type, Expr expr) { 188 return register(new CastExpr(type, expr)); 189 } 190 191 public List<Expr> getBindingExpressions() { 192 return mBindingExpressions; 193 } 194 195 public void addImport(String alias, String type) { 196 Preconditions.checkState(!mImports.containsKey(alias), 197 "%s has already been defined as %s", alias, type); 198 final StaticIdentifierExpr id = staticIdentifier(alias); 199 L.d("adding import %s as %s klass: %s", type, alias, id.getClass().getSimpleName()); 200 id.setUserDefinedType(type); 201 mImports.put(alias, type); 202 } 203 204 public Map<String, String> getImports() { 205 return mImports; 206 } 207 208 /** 209 * The actual thingy that is set on the binding target. 210 * 211 * Input must be already registered 212 */ 213 public Expr bindingExpr(Expr bindingExpr) { 214 Preconditions.checkArgument(mExprMap.containsKey(bindingExpr.getUniqueKey()), 215 "Main expression should already be registered"); 216 if (!mBindingExpressions.contains(bindingExpr)) { 217 mBindingExpressions.add(bindingExpr); 218 } 219 return bindingExpr; 220 } 221 222 /** 223 * Nodes to which no one depends 224 */ 225 public Iterable<Expr> findRootNodes() { 226 return Iterables.filter(mExprMap.values(), new Predicate<Expr>() { 227 @Override 228 public boolean apply(Expr input) { 229 return input.getParents().isEmpty(); 230 } 231 }); 232 } 233 234 /** 235 * Nodes, which do not depend on any other node 236 */ 237 public Iterable<Expr> findLeafNodes() { 238 return Iterables.filter(mExprMap.values(), new Predicate<Expr>() { 239 @Override 240 public boolean apply(Expr input) { 241 return input.getChildren().isEmpty(); 242 } 243 }); 244 } 245 246 public List<Expr> getObservables() { 247 return mObservables; 248 } 249 250 /** 251 * Give id to each expression. Will be useful if we serialize. 252 */ 253 public void seal() { 254 L.d("sealing model"); 255 List<Expr> notifiableExpressions = new ArrayList<Expr>(); 256 //ensure class analyzer. We need to know observables at this point 257 final ModelAnalyzer modelAnalyzer = ModelAnalyzer.getInstance(); 258 259 ArrayList<Expr> exprs = new ArrayList<Expr>(mBindingExpressions); 260 for (Expr expr: exprs) { 261 expr.updateExpr(modelAnalyzer); 262 } 263 264 int counter = 0; 265 final Iterable<Expr> observables = filterObservables(modelAnalyzer); 266 List<String> flagMapping = Lists.newArrayList(); 267 mObservables = Lists.newArrayList(); 268 for (Expr expr : observables) { 269 // observables gets initial ids 270 flagMapping.add(expr.getUniqueKey()); 271 expr.setId(counter++); 272 mObservables.add(expr); 273 notifiableExpressions.add(expr); 274 L.d("observable %s", expr.getUniqueKey()); 275 } 276 277 // non-observable identifiers gets next ids 278 final Iterable<Expr> nonObservableIds = filterNonObservableIds(modelAnalyzer); 279 for (Expr expr : nonObservableIds) { 280 flagMapping.add(expr.getUniqueKey()); 281 expr.setId(counter++); 282 notifiableExpressions.add(expr); 283 L.d("non-observable %s", expr.getUniqueKey()); 284 } 285 286 // descendents of observables gets following ids 287 for (Expr expr : observables) { 288 for (Expr parent : expr.getParents()) { 289 if (parent.hasId()) { 290 continue;// already has some id, means observable 291 } 292 // only fields earn an id 293 if (parent instanceof FieldAccessExpr) { 294 FieldAccessExpr fae = (FieldAccessExpr) parent; 295 L.d("checking field access expr %s. getter: %s", fae,fae.getGetter()); 296 if (fae.isDynamic() && fae.getGetter().canBeInvalidated()) { 297 flagMapping.add(parent.getUniqueKey()); 298 parent.setId(counter++); 299 notifiableExpressions.add(parent); 300 L.d("notifiable field %s : %s for %s : %s", parent.getUniqueKey(), 301 Integer.toHexString(System.identityHashCode(parent)), 302 expr.getUniqueKey(), 303 Integer.toHexString(System.identityHashCode(expr))); 304 } 305 } 306 } 307 } 308 309 // non-dynamic binding expressions receive some ids so that they can be invalidated 310 L.d("list of binding expressions"); 311 for (int i = 0; i < mBindingExpressions.size(); i++) { 312 L.d("[%d] %s", i, mBindingExpressions.get(i)); 313 } 314 // we don't assign ids to constant binding expressions because now invalidateAll has its own 315 // flag. 316 317 for (Expr expr : notifiableExpressions) { 318 expr.enableDirectInvalidation(); 319 } 320 321 // make sure all dependencies are resolved to avoid future race conditions 322 for (Expr expr : mExprMap.values()) { 323 expr.getDependencies(); 324 } 325 final int invalidateAnyFlagIndex = counter ++; 326 flagMapping.add("INVALIDATE ANY"); 327 mInvalidateableFieldLimit = counter; 328 mInvalidateableFlags = new BitSet(); 329 for (int i = 0; i < mInvalidateableFieldLimit; i++) { 330 mInvalidateableFlags.set(i, true); 331 } 332 333 // make sure all dependencies are resolved to avoid future race conditions 334 for (Expr expr : mExprMap.values()) { 335 if (expr.isConditional()) { 336 L.d("requirement id for %s is %d", expr, counter); 337 expr.setRequirementId(counter); 338 flagMapping.add(expr.getUniqueKey() + FALSE_KEY_SUFFIX); 339 flagMapping.add(expr.getUniqueKey() + TRUE_KEY_SUFFIX); 340 counter += 2; 341 } 342 } 343 mConditionalFlags = new BitSet(); 344 for (int i = mInvalidateableFieldLimit; i < counter; i++) { 345 mConditionalFlags.set(i, true); 346 } 347 mRequirementIdCount = (counter - mInvalidateableFieldLimit) / 2; 348 349 // everybody gets an id 350 for (Map.Entry<String, Expr> entry : mExprMap.entrySet()) { 351 final Expr value = entry.getValue(); 352 if (!value.hasId()) { 353 value.setId(counter++); 354 } 355 } 356 357 mFlagMapping = new String[flagMapping.size()]; 358 flagMapping.toArray(mFlagMapping); 359 360 mFlagBucketCount = 1 + (getTotalFlagCount() / FlagSet.sBucketSize); 361 mInvalidateAnyFlags = new BitSet(); 362 mInvalidateAnyFlags.set(invalidateAnyFlagIndex, true); 363 364 for (Expr expr : mExprMap.values()) { 365 expr.getShouldReadFlagsWithConditionals(); 366 } 367 368 for (Expr expr : mExprMap.values()) { 369 // ensure all types are calculated 370 expr.getResolvedType(); 371 } 372 373 mSealed = true; 374 } 375 376 public int getFlagBucketCount() { 377 return mFlagBucketCount; 378 } 379 380 public int getTotalFlagCount() { 381 return mRequirementIdCount * 2 + mInvalidateableFieldLimit; 382 } 383 384 public int getInvalidateableFieldLimit() { 385 return mInvalidateableFieldLimit; 386 } 387 388 public String[] getFlagMapping() { 389 return mFlagMapping; 390 } 391 392 public String getFlag(int id) { 393 return mFlagMapping[id]; 394 } 395 396 private Iterable<Expr> filterNonObservableIds(final ModelAnalyzer modelAnalyzer) { 397 return Iterables.filter(mExprMap.values(), new Predicate<Expr>() { 398 @Override 399 public boolean apply(Expr input) { 400 return input instanceof IdentifierExpr 401 && !input.hasId() 402 && !input.isObservable() 403 && input.isDynamic(); 404 } 405 }); 406 } 407 408 private Iterable<Expr> filterObservables(final ModelAnalyzer modelAnalyzer) { 409 return Iterables.filter(mExprMap.values(), new Predicate<Expr>() { 410 @Override 411 public boolean apply(Expr input) { 412 return input.isObservable(); 413 } 414 }); 415 } 416 417 public List<Expr> getPendingExpressions() { 418 if (mPendingExpressions == null) { 419 mPendingExpressions = Lists.newArrayList(); 420 for (Expr expr : mExprMap.values()) { 421 if (!expr.isRead() && expr.isDynamic()) { 422 mPendingExpressions.add(expr); 423 } 424 } 425 } 426 return mPendingExpressions; 427 } 428 429 public boolean markBitsRead() { 430 // each has should read flags, we set them back on them 431 for (Expr expr : filterShouldRead(getPendingExpressions())) { 432 expr.markFlagsAsRead(expr.getShouldReadFlags()); 433 } 434 return pruneDone(); 435 } 436 437 private boolean pruneDone() { 438 boolean marked = true; 439 List<Expr> markedAsReadList = Lists.newArrayList(); 440 while (marked) { 441 marked = false; 442 for (Expr expr : mExprMap.values()) { 443 if (expr.isRead()) { 444 continue; 445 } 446 if (expr.markAsReadIfDone()) { 447 L.d("marked %s as read ", expr.getUniqueKey()); 448 marked = true; 449 markedAsReadList.add(expr); 450 } 451 452 } 453 } 454 boolean elevated = false; 455 for (Expr markedAsRead : markedAsReadList) { 456 for (Dependency dependency : markedAsRead.getDependants()) { 457 if (dependency.getDependant().considerElevatingConditionals(markedAsRead)) { 458 elevated = true; 459 } 460 } 461 } 462 if (elevated) { 463 // some conditionals are elevated. We should re-calculate flags 464 for (Expr expr : getPendingExpressions()) { 465 if (!expr.isRead()) { 466 expr.invalidateReadFlags(); 467 } 468 } 469 mPendingExpressions = null; 470 } 471 return elevated; 472 } 473 474 public static Iterable<Expr> filterShouldRead(Iterable<Expr> exprs) { 475 return toCollection(Iterables.filter(exprs, sShouldReadPred)); 476 } 477 478 public static List<Expr> toCollection(Iterable<Expr> iterable) { 479 return Arrays.asList(Iterables.toArray(iterable, Expr.class)); 480 } 481 482 private static final Predicate<Expr> sShouldReadPred = new Predicate<Expr>() { 483 @Override 484 public boolean apply(final Expr expr) { 485 return !expr.getShouldReadFlags().isEmpty() && !Iterables.any( 486 expr.getDependencies(), new Predicate<Dependency>() { 487 @Override 488 public boolean apply(Dependency dependency) { 489 final boolean result = dependency.isConditional() || 490 dependency.getOther().hasNestedCannotRead(); 491 return result; 492 } 493 }); 494 } 495 }; 496 497 /** 498 * May return null if flag is equal to invalidate any flag. 499 */ 500 public Expr findFlagExpression(int flag) { 501 if (mInvalidateAnyFlags.get(flag)) { 502 return null; 503 } 504 final String key = mFlagMapping[flag]; 505 if (mExprMap.containsKey(key)) { 506 return mExprMap.get(key); 507 } 508 int falseIndex = key.indexOf(FALSE_KEY_SUFFIX); 509 if (falseIndex > -1) { 510 final String trimmed = key.substring(0, falseIndex); 511 return mExprMap.get(trimmed); 512 } 513 int trueIndex = key.indexOf(TRUE_KEY_SUFFIX); 514 if (trueIndex > -1) { 515 final String trimmed = key.substring(0, trueIndex); 516 return mExprMap.get(trimmed); 517 } 518 // log everything we call 519 StringBuilder error = new StringBuilder(); 520 error.append("cannot find flag:").append(flag).append("\n"); 521 error.append("invalidate any flag:").append(mInvalidateAnyFlags).append("\n"); 522 error.append("key:").append(key).append("\n"); 523 error.append("flag mapping:").append(Arrays.toString(mFlagMapping)); 524 Preconditions.checkArgument(false, error.toString()); 525 return null; 526 } 527 528 public BitSet getInvalidateAnyBitSet() { 529 return mInvalidateAnyFlags; 530 } 531 532 public Expr argListExpr(Iterable<Expr> expressions) { 533 return register(new ArgListExpr(mArgListIdCounter ++, expressions)); 534 } 535} 536