ExprModel.java revision 74f72d77b1db2b78ee6422da2ec94de12edcb6dc
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 private static final String TRUE_KEY_SUFFIX = "== true"; 46 private static final String FALSE_KEY_SUFFIX = "== false"; 47 48 /** 49 * Used by code generation. Keeps the list of expressions that are waiting to be evaluated. 50 */ 51 private List<Expr> mPendingExpressions; 52 53 /** 54 * Used for converting flags into identifiers while debugging. 55 */ 56 private String[] mFlagMapping; 57 58 private BitSet mInvalidateableFlags; 59 private BitSet mConditionalFlags; 60 61 private int mFlagBucketCount;// how many buckets we use to identify flags 62 63 private List<Expr> mObservables; 64 65 private Map<String, String> mImports = new HashMap<String, String>(); 66 67 /** 68 * Adds the expression to the list of expressions and returns it. 69 * If it already exists, returns existing one. 70 * 71 * @param expr The new parsed expression 72 * @return The expression itself or another one if the same thing was parsed before 73 */ 74 public <T extends Expr> T register(T expr) { 75 T existing = (T) mExprMap.get(expr.getUniqueKey()); 76 if (existing != null) { 77 Preconditions.checkState(expr.getParents().isEmpty(), 78 "If an expression already exists, it should've never been added to a parent," 79 + "if thats the case, somewhere we are creating an expression w/o" 80 + "calling expression model"); 81 // tell the expr that it is being swapped so that if it was added to some other expr 82 // as a parent, those can swap their references 83 expr.onSwappedWith(existing); 84 return existing; 85 } 86 mExprMap.put(expr.getUniqueKey(), expr); 87 expr.setModel(this); 88 return expr; 89 } 90 91 public void unregister(Expr expr) { 92 mExprMap.remove(expr.getUniqueKey()); 93 } 94 95 public Map<String, Expr> getExprMap() { 96 return mExprMap; 97 } 98 99 public int size() { 100 return mExprMap.size(); 101 } 102 103 public ComparisonExpr comparison(String op, Expr left, Expr right) { 104 return register(new ComparisonExpr(op, left, right)); 105 } 106 107 public FieldAccessExpr field(Expr parent, String name) { 108 return register(new FieldAccessExpr(parent, name)); 109 } 110 111 public FieldAccessExpr observableField(Expr parent, String name) { 112 return register(new FieldAccessExpr(parent, name, true)); 113 } 114 115 public SymbolExpr symbol(String text, Class type) { 116 return register(new SymbolExpr(text, type)); 117 } 118 119 public TernaryExpr ternary(Expr pred, Expr ifTrue, Expr ifFalse) { 120 return register(new TernaryExpr(pred, ifTrue, ifFalse)); 121 } 122 123 public IdentifierExpr identifier(String name) { 124 return register(new IdentifierExpr(name)); 125 } 126 127 public StaticIdentifierExpr staticIdentifier(String name) { 128 return register(new StaticIdentifierExpr(name)); 129 } 130 131 public MethodCallExpr methodCall(Expr target, String name, List<Expr> args) { 132 return register(new MethodCallExpr(target, name, args)); 133 } 134 135 public MathExpr math(Expr left, String op, Expr right) { 136 return register(new MathExpr(left, op, right)); 137 } 138 139 public Expr group(Expr grouped) { 140 return register(new GroupExpr(grouped)); 141 } 142 143 public Expr resourceExpr(String packageName, String resourceType, String resourceName, 144 List<Expr> args) { 145 return register(new ResourceExpr(packageName, resourceType, resourceName, args)); 146 } 147 148 public Expr bracketExpr(Expr variableExpr, Expr argExpr) { 149 return register(new BracketExpr(variableExpr, argExpr)); 150 } 151 152 public Expr castExpr(String type, Expr expr) { 153 return register(new CastExpr(type, expr)); 154 } 155 156 public List<Expr> getBindingExpressions() { 157 return mBindingExpressions; 158 } 159 160 public void addImport(String alias, String type) { 161 Preconditions.checkState(!mImports.containsKey(alias), 162 "%s has already been defined as %s", alias, type); 163 final StaticIdentifierExpr id = staticIdentifier(alias); 164 L.d("adding import %s as %s klass: %s", type, alias, id.getClass().getSimpleName()); 165 id.setUserDefinedType(type); 166 mImports.put(alias, type); 167 } 168 169 public Map<String, String> getImports() { 170 return mImports; 171 } 172 173 /** 174 * The actual thingy that is set on the binding target. 175 * 176 * Input must be already registered 177 */ 178 public Expr bindingExpr(Expr bindingExpr) { 179 Preconditions.checkArgument(mExprMap.containsKey(bindingExpr.getUniqueKey()), 180 "Main expression should already be registered"); 181 if (!mBindingExpressions.contains(bindingExpr)) { 182 mBindingExpressions.add(bindingExpr); 183 } 184 return bindingExpr; 185 } 186 187 /** 188 * Nodes to which no one depends 189 */ 190 public Iterable<Expr> findRootNodes() { 191 return Iterables.filter(mExprMap.values(), new Predicate<Expr>() { 192 @Override 193 public boolean apply(Expr input) { 194 return input.getParents().isEmpty(); 195 } 196 }); 197 } 198 199 /** 200 * Nodes, which do not depend on any other node 201 */ 202 public Iterable<Expr> findLeafNodes() { 203 return Iterables.filter(mExprMap.values(), new Predicate<Expr>() { 204 @Override 205 public boolean apply(Expr input) { 206 return input.getChildren().isEmpty(); 207 } 208 }); 209 } 210 211 public List<Expr> getObservables() { 212 return mObservables; 213 } 214 215 /** 216 * Give id to each expression. Will be useful if we serialize. 217 */ 218 public void seal() { 219 List<Expr> notifiableExpressions = new ArrayList<Expr>(); 220 //ensure class analyzer. We need to know observables at this point 221 final ModelAnalyzer modelAnalyzer = ModelAnalyzer.getInstance(); 222 223 ArrayList<Expr> exprs = new ArrayList<Expr>(mBindingExpressions); 224 for (Expr expr: exprs) { 225 expr.updateExpr(modelAnalyzer); 226 } 227 228 int counter = 0; 229 final Iterable<Expr> observables = filterObservables(modelAnalyzer); 230 List<String> flagMapping = Lists.newArrayList(); 231 mObservables = Lists.newArrayList(); 232 for (Expr expr : observables) { 233 // observables gets initial ids 234 flagMapping.add(expr.getUniqueKey()); 235 expr.setId(counter++); 236 mObservables.add(expr); 237 notifiableExpressions.add(expr); 238 L.d("observable %s", expr.getUniqueKey()); 239 } 240 241 // non-observable identifiers gets next ids 242 final Iterable<Expr> nonObservableIds = filterNonObservableIds(modelAnalyzer); 243 for (Expr expr : nonObservableIds) { 244 flagMapping.add(expr.getUniqueKey()); 245 expr.setId(counter++); 246 notifiableExpressions.add(expr); 247 L.d("non-observable %s", expr.getUniqueKey()); 248 } 249 250 // descendents of observables gets following ids 251 for (Expr expr : observables) { 252 for (Expr parent : expr.getParents()) { 253 if (parent.hasId()) { 254 continue;// already has some id, means observable 255 } 256 // only fields earn an id 257 if (parent instanceof FieldAccessExpr) { 258 FieldAccessExpr fae = (FieldAccessExpr) parent; 259 L.d("checking field access expr %s. getter: %s", fae,fae.getGetter()); 260 if (fae.isDynamic() && fae.getGetter().canBeInvalidated) { 261 flagMapping.add(parent.getUniqueKey()); 262 parent.setId(counter++); 263 notifiableExpressions.add(parent); 264 L.d("notifiable field %s : %s for %s : %s", parent.getUniqueKey(), 265 Integer.toHexString(System.identityHashCode(parent)), 266 expr.getUniqueKey(), 267 Integer.toHexString(System.identityHashCode(expr))); 268 } 269 } 270 } 271 } 272 273 // non-dynamic binding expressions receive some ids so that they can be invalidated 274 for (int i = 0; i < mBindingExpressions.size(); i++) { 275 L.d("[" + i + "] " + mBindingExpressions.get(i)); 276 } 277 for (Expr expr : mBindingExpressions) { 278 if (!(expr.isDynamic() || !expr.hasId())) { 279 L.d("Expr " + expr + " is dynamic? " + expr.isDynamic() + ", has ID? " + expr.hasId()); 280 } 281 Preconditions.checkState(expr.isDynamic() || !expr.hasId()); 282 if (!expr.isDynamic()) { 283 // give it an id for invalidateAll 284 expr.setId(counter ++); 285 notifiableExpressions.add(expr); 286 } 287 } 288 289 for (Expr expr : notifiableExpressions) { 290 expr.enableDirectInvalidation(); 291 } 292 293 // make sure all dependencies are resolved to avoid future race conditions 294 for (Expr expr : mExprMap.values()) { 295 expr.getDependencies(); 296 } 297 298 mInvalidateableFieldLimit = counter; 299 mInvalidateableFlags = new BitSet(); 300 for (int i = 0; i < mInvalidateableFieldLimit; i++) { 301 mInvalidateableFlags.set(i, true); 302 } 303 304 // make sure all dependencies are resolved to avoid future race conditions 305 for (Expr expr : mExprMap.values()) { 306 if (expr.isConditional()) { 307 expr.setRequirementId(counter); 308 flagMapping.add(expr.getUniqueKey() + FALSE_KEY_SUFFIX); 309 flagMapping.add(expr.getUniqueKey() + TRUE_KEY_SUFFIX); 310 counter += 2; 311 } 312 } 313 mConditionalFlags = new BitSet(); 314 for (int i = mInvalidateableFieldLimit; i < counter; i++) { 315 mConditionalFlags.set(i, true); 316 } 317 318 mRequirementIdCount = (counter - mInvalidateableFieldLimit) / 2; 319 320 // everybody gets an id 321 for (Map.Entry<String, Expr> entry : mExprMap.entrySet()) { 322 final Expr value = entry.getValue(); 323 if (!value.hasId()) { 324 value.setId(counter++); 325 } 326 } 327 mFlagMapping = new String[flagMapping.size()]; 328 flagMapping.toArray(mFlagMapping); 329 330 for (Expr expr : mExprMap.values()) { 331 expr.getShouldReadFlagsWithConditionals(); 332 } 333 334 for (Expr expr : mExprMap.values()) { 335 // ensure all types are calculated 336 expr.getResolvedType(); 337 } 338 339 mFlagBucketCount = 1 + (getTotalFlagCount() / FlagSet.sBucketSize); 340 } 341 342 public int getFlagBucketCount() { 343 return mFlagBucketCount; 344 } 345 346 public int getTotalFlagCount() { 347 return mRequirementIdCount * 2 + mInvalidateableFieldLimit; 348 } 349 350 public int getInvalidateableFieldLimit() { 351 return mInvalidateableFieldLimit; 352 } 353 354 public String[] getFlagMapping() { 355 return mFlagMapping; 356 } 357 358 public String getFlag(int id) { 359 return mFlagMapping[id]; 360 } 361 362 private Iterable<Expr> filterNonObservableIds(final ModelAnalyzer modelAnalyzer) { 363 return Iterables.filter(mExprMap.values(), new Predicate<Expr>() { 364 @Override 365 public boolean apply(Expr input) { 366 return input instanceof IdentifierExpr 367 && !input.hasId() 368 && !input.isObservable() 369 && input.isDynamic(); 370 } 371 }); 372 } 373 374 private Iterable<Expr> filterObservables(final ModelAnalyzer modelAnalyzer) { 375 return Iterables.filter(mExprMap.values(), new Predicate<Expr>() { 376 @Override 377 public boolean apply(Expr input) { 378 return input.isObservable(); 379 } 380 }); 381 } 382 383 public List<Expr> getPendingExpressions() { 384 if (mPendingExpressions == null) { 385 mPendingExpressions = Lists.newArrayList(); 386 for (Expr expr : mExprMap.values()) { 387 if (!expr.isRead() && expr.isDynamic()) { 388 mPendingExpressions.add(expr); 389 } 390 } 391 } 392 return mPendingExpressions; 393 } 394 395 public boolean markBitsRead() { 396 L.d("marking bits as done"); 397 // each has should read flags, we set them back on them 398 for (Expr expr : filterShouldRead(getPendingExpressions())) { 399 expr.markFlagsAsRead(expr.getShouldReadFlags()); 400 } 401 return pruneDone(); 402 } 403 404 private boolean pruneDone() { 405 boolean marked = true; 406 List<Expr> markedAsReadList = Lists.newArrayList(); 407 while (marked) { 408 marked = false; 409 for (Expr expr : mExprMap.values()) { 410 if (expr.isRead()) { 411 continue; 412 } 413 if (expr.markAsReadIfDone()) { 414 L.d("marked %s as read ", expr.getUniqueKey()); 415 marked = true; 416 markedAsReadList.add(expr); 417 } 418 419 } 420 } 421 boolean elevated = false; 422 for (Expr markedAsRead : markedAsReadList) { 423 for (Dependency dependency : markedAsRead.getDependants()) { 424 if (dependency.getDependant().considerElevatingConditionals(markedAsRead)) { 425 elevated = true; 426 } 427 } 428 } 429 if (elevated) { 430 // some conditionals are elevated. We should re-calculate flags 431 for (Expr expr : getPendingExpressions()) { 432 if (!expr.isRead()) { 433 expr.invalidateReadFlags(); 434 } 435 } 436 mPendingExpressions = null; 437 } 438 return elevated; 439 } 440 441 public static Iterable<Expr> filterShouldRead(Iterable<Expr> exprs) { 442 return toCollection(Iterables.filter(exprs, sShouldReadPred)); 443 } 444 445 public static List<Expr> toCollection(Iterable<Expr> iterable) { 446 return Arrays.asList(Iterables.toArray(iterable, Expr.class)); 447 } 448 449 private static final Predicate<Expr> sShouldReadPred = new Predicate<Expr>() { 450 @Override 451 public boolean apply(final Expr expr) { 452 return !expr.getShouldReadFlags().isEmpty() && !Iterables.any( 453 expr.getDependencies(), new Predicate<Dependency>() { 454 @Override 455 public boolean apply(Dependency dependency) { 456 final boolean result = dependency.isConditional() || 457 dependency.getOther().hasNestedCannotRead(); 458 return result; 459 } 460 }); 461 } 462 }; 463 464 private static final Predicate<Expr> sReadNowPred = new Predicate<Expr>() { 465 @Override 466 public boolean apply(Expr input) { 467 return !input.getShouldReadFlags().isEmpty() && 468 !Iterables.any(input.getDependencies(), new Predicate<Dependency>() { 469 @Override 470 public boolean apply(Dependency input) { 471 return !input.getOther().isRead(); 472 } 473 }); 474 } 475 }; 476 477 public Expr findFlagExpression(int flag) { 478 final String key = mFlagMapping[flag]; 479 if (mExprMap.containsKey(key)) { 480 return mExprMap.get(key); 481 } 482 int falseIndex = key.indexOf(FALSE_KEY_SUFFIX); 483 if (falseIndex > -1) { 484 final String trimmed = key.substring(0, falseIndex); 485 return mExprMap.get(trimmed); 486 } 487 int trueIndex = key.indexOf(TRUE_KEY_SUFFIX); 488 if (trueIndex > -1) { 489 final String trimmed = key.substring(0, trueIndex); 490 return mExprMap.get(trimmed); 491 } 492 Preconditions.checkArgument(false, "cannot find expression for flag %d", flag); 493 return null; 494 } 495} 496