1 /*
2 * Copyright (c) 2011, 2016, 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.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 */
23
24
25 package org.graalvm.compiler.hotspot;
26
27 import static jdk.vm.ci.common.InitTimer.timer;
28 import static jdk.vm.ci.hotspot.HotSpotJVMCIRuntime.runtime;
29 import static org.graalvm.compiler.core.common.GraalOptions.GeneratePIC;
30 import static org.graalvm.compiler.core.common.GraalOptions.HotSpotPrintInlining;
31 import static org.graalvm.compiler.debug.DebugContext.DEFAULT_LOG_STREAM;
32
33 import java.util.ArrayList;
34 import java.util.EnumMap;
35 import java.util.List;
36 import java.util.Map;
37 import java.util.concurrent.atomic.AtomicReference;
38
39 import jdk.internal.vm.compiler.collections.EconomicMap;
40 import jdk.internal.vm.compiler.collections.EconomicSet;
41 import jdk.internal.vm.compiler.collections.Equivalence;
42 import jdk.internal.vm.compiler.collections.UnmodifiableMapCursor;
43 import org.graalvm.compiler.api.replacements.SnippetReflectionProvider;
44 import org.graalvm.compiler.api.runtime.GraalRuntime;
45 import org.graalvm.compiler.core.CompilationWrapper.ExceptionAction;
46 import org.graalvm.compiler.core.common.CompilationIdentifier;
47 import org.graalvm.compiler.core.common.GraalOptions;
48 import org.graalvm.compiler.core.target.Backend;
49 import org.graalvm.compiler.debug.DebugContext;
50 import org.graalvm.compiler.debug.DebugContext.Description;
51 import org.graalvm.compiler.debug.DebugHandlersFactory;
52 import org.graalvm.compiler.debug.DebugOptions;
53 import org.graalvm.compiler.debug.DiagnosticsOutputDirectory;
54 import org.graalvm.compiler.debug.GlobalMetrics;
55 import org.graalvm.compiler.debug.GraalError;
56 import org.graalvm.compiler.debug.TTY;
57 import org.graalvm.compiler.hotspot.CompilationStatistics.Options;
58 import org.graalvm.compiler.hotspot.CompilerConfigurationFactory.BackendMap;
59 import org.graalvm.compiler.hotspot.debug.BenchmarkCounters;
60 import org.graalvm.compiler.hotspot.meta.HotSpotProviders;
61 import org.graalvm.compiler.nodes.spi.StampProvider;
62 import org.graalvm.compiler.options.EnumOptionKey;
63 import org.graalvm.compiler.options.OptionDescriptor;
64 import org.graalvm.compiler.options.OptionDescriptors;
65 import org.graalvm.compiler.options.OptionKey;
66 import org.graalvm.compiler.options.OptionValues;
67 import org.graalvm.compiler.options.OptionsParser;
68 import org.graalvm.compiler.phases.tiers.CompilerConfiguration;
69 import org.graalvm.compiler.replacements.SnippetCounter;
70 import org.graalvm.compiler.replacements.SnippetCounter.Group;
71 import org.graalvm.compiler.runtime.RuntimeProvider;
72 import org.graalvm.compiler.serviceprovider.GraalServices;
73
74 import jdk.vm.ci.code.Architecture;
75 import jdk.vm.ci.code.stack.StackIntrospection;
76 import jdk.vm.ci.common.InitTimer;
77 import jdk.vm.ci.hotspot.HotSpotCompilationRequest;
78 import jdk.vm.ci.hotspot.HotSpotJVMCIRuntime;
79 import jdk.vm.ci.hotspot.HotSpotResolvedJavaMethod;
80 import jdk.vm.ci.hotspot.HotSpotResolvedJavaType;
81 import jdk.vm.ci.hotspot.HotSpotResolvedObjectType;
82 import jdk.vm.ci.hotspot.HotSpotVMConfigStore;
83 import jdk.vm.ci.meta.JavaKind;
84 import jdk.vm.ci.meta.MetaAccessProvider;
85 import jdk.vm.ci.meta.ResolvedJavaMethod;
86 import jdk.vm.ci.meta.ResolvedJavaType;
87 import jdk.vm.ci.runtime.JVMCI;
88 import jdk.vm.ci.runtime.JVMCIBackend;
89
90 //JaCoCo Exclude
91
92 /**
93 * Singleton class holding the instance of the {@link GraalRuntime}.
94 */
95 public final class HotSpotGraalRuntime implements HotSpotGraalRuntimeProvider {
96
97 private static boolean checkArrayIndexScaleInvariants(MetaAccessProvider metaAccess) {
98 assert metaAccess.getArrayIndexScale(JavaKind.Byte) == 1;
99 assert metaAccess.getArrayIndexScale(JavaKind.Boolean) == 1;
100 assert metaAccess.getArrayIndexScale(JavaKind.Char) == 2;
101 assert metaAccess.getArrayIndexScale(JavaKind.Short) == 2;
102 assert metaAccess.getArrayIndexScale(JavaKind.Int) == 4;
103 assert metaAccess.getArrayIndexScale(JavaKind.Long) == 8;
104 assert metaAccess.getArrayIndexScale(JavaKind.Float) == 4;
105 assert metaAccess.getArrayIndexScale(JavaKind.Double) == 8;
106 return true;
107 }
108
109 private final String runtimeName;
110 private final String compilerConfigurationName;
111 private final HotSpotBackend hostBackend;
112 private final GlobalMetrics metricValues = new GlobalMetrics();
113 private final List<SnippetCounter.Group> snippetCounterGroups;
114 private final HotSpotGC garbageCollector;
115
116 private final EconomicMap<Class<? extends Architecture>, HotSpotBackend> backends = EconomicMap.create(Equivalence.IDENTITY);
117
118 private final GraalHotSpotVMConfig config;
119
120 /**
121 * The options can be {@linkplain #setOptionValues(String[], String[]) updated} by external
122 * interfaces such as JMX. This comes with the risk that inconsistencies can arise as an
123 * {@link OptionValues} object can be cached by various parts of Graal instead of always
124 * obtaining them from this object. However, concurrent updates are never lost.
125 */
126 private AtomicReference<OptionValues> optionsRef = new AtomicReference<>();
127
128 private final HotSpotGraalCompiler compiler;
129
130 private final DiagnosticsOutputDirectory outputDirectory;
131 private final Map<ExceptionAction, Integer> compilationProblemsPerAction;
132
133 /**
134 * @param nameQualifier a qualifier to be added to this runtime's {@linkplain #getName() name}
135 * @param compilerConfigurationFactory factory for the compiler configuration
136 * {@link CompilerConfigurationFactory#selectFactory(String, OptionValues)}
137 */
138 @SuppressWarnings("try")
139 HotSpotGraalRuntime(String nameQualifier, HotSpotJVMCIRuntime jvmciRuntime, CompilerConfigurationFactory compilerConfigurationFactory, OptionValues initialOptions) {
140 this.runtimeName = getClass().getSimpleName() + ":" + nameQualifier;
141 HotSpotVMConfigStore store = jvmciRuntime.getConfigStore();
142 config = GeneratePIC.getValue(initialOptions) ? new AOTGraalHotSpotVMConfig(store) : new GraalHotSpotVMConfig(store);
143
144 // Only set HotSpotPrintInlining if it still has its default value (false).
145 if (GraalOptions.HotSpotPrintInlining.getValue(initialOptions) == false && config.printInlining) {
146 optionsRef.set(new OptionValues(initialOptions, HotSpotPrintInlining, true));
147 } else {
148 optionsRef.set(initialOptions);
149 }
150 OptionValues options = optionsRef.get();
151
152 garbageCollector = getSelectedGC();
153
154 outputDirectory = new DiagnosticsOutputDirectory(options);
155 compilationProblemsPerAction = new EnumMap<>(ExceptionAction.class);
156 snippetCounterGroups = GraalOptions.SnippetCounters.getValue(options) ? new ArrayList<>() : null;
157 CompilerConfiguration compilerConfiguration = compilerConfigurationFactory.createCompilerConfiguration();
158 compilerConfigurationName = compilerConfigurationFactory.getName();
159
160 compiler = new HotSpotGraalCompiler(jvmciRuntime, this, options);
161 management = GraalServices.loadSingle(HotSpotGraalManagementRegistration.class, false);
162 if (management != null) {
163 management.initialize(this);
164 }
165
166 BackendMap backendMap = compilerConfigurationFactory.createBackendMap();
167
168 JVMCIBackend hostJvmciBackend = jvmciRuntime.getHostJVMCIBackend();
169 Architecture hostArchitecture = hostJvmciBackend.getTarget().arch;
170 try (InitTimer t = timer("create backend:", hostArchitecture)) {
171 HotSpotBackendFactory factory = backendMap.getBackendFactory(hostArchitecture);
172 if (factory == null) {
173 throw new GraalError("No backend available for host architecture \"%s\"", hostArchitecture);
174 }
175 hostBackend = registerBackend(factory.createBackend(this, compilerConfiguration, jvmciRuntime, null));
176 }
177
178 for (JVMCIBackend jvmciBackend : jvmciRuntime.getJVMCIBackends().values()) {
179 if (jvmciBackend == hostJvmciBackend) {
180 continue;
181 }
182
183 Architecture gpuArchitecture = jvmciBackend.getTarget().arch;
184 HotSpotBackendFactory factory = backendMap.getBackendFactory(gpuArchitecture);
185 if (factory == null) {
186 throw new GraalError("No backend available for specified GPU architecture \"%s\"", gpuArchitecture);
187 }
188 try (InitTimer t = timer("create backend:", gpuArchitecture)) {
189 registerBackend(factory.createBackend(this, compilerConfiguration, null, hostBackend));
190 }
191 }
192
193 // Complete initialization of backends
194 try (InitTimer st = timer(hostBackend.getTarget().arch.getName(), ".completeInitialization")) {
195 hostBackend.completeInitialization(jvmciRuntime, options);
196 }
197 for (HotSpotBackend backend : backends.getValues()) {
198 if (backend != hostBackend) {
199 try (InitTimer st = timer(backend.getTarget().arch.getName(), ".completeInitialization")) {
200 backend.completeInitialization(jvmciRuntime, options);
201 }
202 }
203 }
204
205 BenchmarkCounters.initialize(jvmciRuntime, options);
206
207 assert checkArrayIndexScaleInvariants(hostJvmciBackend.getMetaAccess());
208
209 runtimeStartTime = System.nanoTime();
210 bootstrapJVMCI = config.getFlag("BootstrapJVMCI", Boolean.class);
211 }
212
213 /**
214 * Constants denoting the GC algorithms available in HotSpot.
215 */
216 public enum HotSpotGC {
217 // Supported GCs
218 Serial(true, "UseSerialGC"),
219 Parallel(true, "UseParallelGC", "UseParallelOldGC", "UseParNewGC"),
220 CMS(true, "UseConcMarkSweepGC"),
221 G1(true, "UseG1GC"),
222
223 // Unsupported GCs
224 Epsilon(false, "UseEpsilonGC"),
225 Z(false, "UseZGC");
226
227 HotSpotGC(boolean supported, String... flags) {
228 this.supported = supported;
229 this.flags = flags;
230 }
231
232 final boolean supported;
233 private final String[] flags;
234
235 public boolean isSelected(GraalHotSpotVMConfig config) {
236 for (String flag : flags) {
237 final boolean notPresent = false;
238 if (config.getFlag(flag, Boolean.class, notPresent)) {
239 return true;
240 }
241 }
242 return false;
243 }
244
245 }
246
247 private HotSpotGC getSelectedGC() throws GraalError {
248 for (HotSpotGC gc : HotSpotGC.values()) {
249 if (gc.isSelected(config)) {
250 if (!gc.supported) {
251 throw new GraalError(gc.name() + " garbage collector is not supported by Graal");
252 }
253 return gc;
254 }
255 }
256 // As of JDK 9, exactly one GC flag is guaranteed to be selected.
257 // On JDK 8, the default GC is Serial when no GC flag is true.
258 return HotSpotGC.Serial;
259 }
260
261 private HotSpotBackend registerBackend(HotSpotBackend backend) {
262 Class<? extends Architecture> arch = backend.getTarget().arch.getClass();
263 HotSpotBackend oldValue = backends.put(arch, backend);
264 assert oldValue == null : "cannot overwrite existing backend for architecture " + arch.getSimpleName();
265 return backend;
266 }
267
268 @Override
269 public HotSpotProviders getHostProviders() {
270 return getHostBackend().getProviders();
271 }
272
273 @Override
274 public GraalHotSpotVMConfig getVMConfig() {
275 return config;
276 }
277
278 @Override
279 public DebugContext openDebugContext(OptionValues compilationOptions, CompilationIdentifier compilationId, Object compilable, Iterable<DebugHandlersFactory> factories) {
280 if (management != null && management.poll(false) != null) {
281 if (compilable instanceof HotSpotResolvedJavaMethod) {
282 HotSpotResolvedObjectType type = ((HotSpotResolvedJavaMethod) compilable).getDeclaringClass();
283 if (type instanceof HotSpotResolvedJavaType) {
284 Class<?> clazz = runtime().getMirror(type);
285 try {
286 ClassLoader cl = clazz.getClassLoader();
287 if (cl != null) {
288 loaders.add(cl);
289 }
290 } catch (SecurityException e) {
291 // This loader can obviously not be used for resolving class names
292 }
293 }
294 }
295 }
296 Description description = new Description(compilable, compilationId.toString(CompilationIdentifier.Verbosity.ID));
297 return DebugContext.create(compilationOptions, description, metricValues, DEFAULT_LOG_STREAM, factories);
298 }
299
300 @Override
301 public OptionValues getOptions() {
302 return optionsRef.get();
303 }
304
305 @Override
306 public Group createSnippetCounterGroup(String groupName) {
307 if (snippetCounterGroups != null) {
308 Group group = new Group(groupName);
309 snippetCounterGroups.add(group);
310 return group;
311 }
312 return null;
313 }
314
315 @Override
316 public String getName() {
317 return runtimeName;
318 }
319
320 @SuppressWarnings("unchecked")
321 @Override
322 public <T> T getCapability(Class<T> clazz) {
323 if (clazz == RuntimeProvider.class) {
324 return (T) this;
325 } else if (clazz == OptionValues.class) {
326 return (T) optionsRef.get();
327 } else if (clazz == StackIntrospection.class) {
328 return (T) this;
329 } else if (clazz == SnippetReflectionProvider.class) {
330 return (T) getHostProviders().getSnippetReflection();
331 } else if (clazz == StampProvider.class) {
332 return (T) getHostProviders().getStampProvider();
333 }
334 return null;
335 }
336
337 public HotSpotGC getGarbageCollector() {
338 return garbageCollector;
339 }
340
341 @Override
342 public HotSpotBackend getHostBackend() {
343 return hostBackend;
344 }
345
346 @Override
347 public <T extends Architecture> Backend getBackend(Class<T> arch) {
348 assert arch != Architecture.class;
349 return backends.get(arch);
350 }
351
352 @Override
353 public String getCompilerConfigurationName() {
354 return compilerConfigurationName;
355 }
356
357 private long runtimeStartTime;
358 private boolean shutdown;
359
360 /**
361 * Take action related to entering a new execution phase.
362 *
363 * @param phase the execution phase being entered
364 */
365 void phaseTransition(String phase) {
366 if (Options.UseCompilationStatistics.getValue(optionsRef.get())) {
367 CompilationStatistics.clear(phase);
368 }
369 }
370
371 void shutdown() {
372 shutdown = true;
373 metricValues.print(optionsRef.get());
374
375 phaseTransition("final");
376
377 if (snippetCounterGroups != null) {
378 for (Group group : snippetCounterGroups) {
379 TTY.out().out().println(group);
380 }
381 }
382 BenchmarkCounters.shutdown(runtime(), optionsRef.get(), runtimeStartTime);
383
384 outputDirectory.close();
385 }
386
387 void clearMetrics() {
388 metricValues.clear();
389 }
390
391 private final boolean bootstrapJVMCI;
392 private boolean bootstrapFinished;
393
394 public void notifyBootstrapFinished() {
395 bootstrapFinished = true;
396 }
397
398 @Override
399 public boolean isBootstrapping() {
400 return bootstrapJVMCI && !bootstrapFinished;
401 }
402
403 @Override
404 public boolean isShutdown() {
405 return shutdown;
406 }
407
408 @Override
409 public DiagnosticsOutputDirectory getOutputDirectory() {
410 return outputDirectory;
411 }
412
413 @Override
414 public Map<ExceptionAction, Integer> getCompilationProblemsPerAction() {
415 return compilationProblemsPerAction;
416 }
417
418 // ------- Management interface ---------
419
420 private final HotSpotGraalManagementRegistration management;
421
422 /**
423 * @returns the management object for this runtime or {@code null}
424 */
425 public HotSpotGraalManagementRegistration getManagement() {
426 return management;
427 }
428
429 /**
430 * Set of weak references to {@link ClassLoader}s available for resolving class names present in
431 * management {@linkplain #invokeManagementAction(String, Object[]) action} arguments.
432 */
433 private final WeakClassLoaderSet loaders = new WeakClassLoaderSet(ClassLoader.getSystemClassLoader());
434
435 /**
436 * Sets or updates this object's {@linkplain #getOptions() options} from {@code names} and
437 * {@code values}.
438 *
439 * @param values the values to set. The empty string represents {@code null} which resets an
440 * option to its default value. For string type options, a non-empty value must be
441 * enclosed in double quotes.
442 * @return an array of Strings where the element at index i is {@code names[i]} if setting the
443 * denoted option succeeded, {@code null} if the option is unknown otherwise an error
444 * message describing the failure to set the option
445 */
446 public String[] setOptionValues(String[] names, String[] values) {
447 EconomicMap<String, OptionDescriptor> optionDescriptors = getOptionDescriptors();
448 EconomicMap<OptionKey<?>, Object> newValues = EconomicMap.create(names.length);
449 EconomicSet<OptionKey<?>> resetValues = EconomicSet.create(names.length);
450 String[] result = new String[names.length];
451 for (int i = 0; i < names.length; i++) {
452 String name = names[i];
453 OptionDescriptor option = optionDescriptors.get(name);
454 if (option != null) {
455 String svalue = values[i];
456 Class<?> optionValueType = option.getOptionValueType();
457 OptionKey<?> optionKey = option.getOptionKey();
458 if (svalue == null || svalue.isEmpty() && !(optionKey instanceof EnumOptionKey)) {
459 resetValues.add(optionKey);
460 result[i] = name;
461 } else {
462 String valueToParse;
463 if (optionValueType == String.class) {
464 if (svalue.length() < 2 || svalue.charAt(0) != '"' || svalue.charAt(svalue.length() - 1) != '"') {
465 result[i] = "Invalid value for String option '" + name + "': must be the empty string or be enclosed in double quotes: " + svalue;
466 continue;
467 } else {
468 valueToParse = svalue.substring(1, svalue.length() - 1);
469 }
470 } else {
471 valueToParse = svalue;
472 }
473 try {
474 OptionsParser.parseOption(name, valueToParse, newValues, OptionsParser.getOptionsLoader());
475 result[i] = name;
476 } catch (IllegalArgumentException e) {
477 result[i] = e.getMessage();
478 continue;
479 }
480 }
481 } else {
482 result[i] = null;
483 }
484 }
485
486 OptionValues currentOptions;
487 OptionValues newOptions;
488 do {
489 currentOptions = optionsRef.get();
490 UnmodifiableMapCursor<OptionKey<?>, Object> cursor = currentOptions.getMap().getEntries();
491 while (cursor.advance()) {
492 OptionKey<?> key = cursor.getKey();
493 if (!resetValues.contains(key) && !newValues.containsKey(key)) {
494 newValues.put(key, OptionValues.decodeNull(cursor.getValue()));
495 }
496 }
497 newOptions = new OptionValues(newValues);
498 } while (!optionsRef.compareAndSet(currentOptions, newOptions));
499
500 return result;
501 }
502
503 /**
504 * Gets the values for the options corresponding to {@code names} encoded as strings. The empty
505 * string represents {@code null}. For string type options, non-{@code null} values will be
506 * enclosed in double quotes.
507 *
508 * @param names a list of option names
509 * @return the values for each named option. If an element in {@code names} does not denote an
510 * existing option, the corresponding element in the returned array will be {@code null}
511 */
512 public String[] getOptionValues(String... names) {
513 String[] values = new String[names.length];
514 EconomicMap<String, OptionDescriptor> optionDescriptors = getOptionDescriptors();
515 for (int i = 0; i < names.length; i++) {
516 OptionDescriptor option = optionDescriptors.get(names[i]);
517 if (option != null) {
518 OptionKey<?> optionKey = option.getOptionKey();
519 Object value = optionKey.getValue(getOptions());
520 String svalue;
521 if (option.getOptionValueType() == String.class && value != null) {
522 svalue = "\"" + value + "\"";
523 } else if (value == null) {
524 svalue = "";
525 } else {
526 svalue = String.valueOf(value);
527 }
528 values[i] = svalue;
529 } else {
530 // null denotes the option does not exist
531 values[i] = null;
532 }
533 }
534 return values;
535 }
536
537 private static EconomicMap<String, OptionDescriptor> getOptionDescriptors() {
538 EconomicMap<String, OptionDescriptor> result = EconomicMap.create();
539 for (OptionDescriptors set : OptionsParser.getOptionsLoader()) {
540 for (OptionDescriptor option : set) {
541 result.put(option.getName(), option);
542 }
543 }
544 return result;
545 }
546
547 private void dumpMethod(String className, String methodName, String filter, String host, int port) throws Exception {
548 EconomicSet<ClassNotFoundException> failures = EconomicSet.create();
549 EconomicSet<Class<?>> found = loaders.resolve(className, failures);
550 if (found.isEmpty()) {
551 ClassNotFoundException cause = failures.isEmpty() ? new ClassNotFoundException(className) : failures.iterator().next();
552 throw new Exception("Cannot find class " + className + " to schedule recompilation", cause);
553 }
554 for (Class<?> clazz : found) {
555 ResolvedJavaType type = JVMCI.getRuntime().getHostJVMCIBackend().getMetaAccess().lookupJavaType(clazz);
556 for (ResolvedJavaMethod method : type.getDeclaredMethods()) {
557 if (methodName.equals(method.getName()) && method instanceof HotSpotResolvedJavaMethod) {
558 HotSpotResolvedJavaMethod hotSpotMethod = (HotSpotResolvedJavaMethod) method;
559 dumpMethod(hotSpotMethod, filter, host, port);
560 }
561 }
562 }
563 }
564
565 private void dumpMethod(HotSpotResolvedJavaMethod hotSpotMethod, String filter, String host, int port) throws Exception {
566 EconomicMap<OptionKey<?>, Object> extra = EconomicMap.create();
567 extra.put(DebugOptions.Dump, filter);
568 extra.put(DebugOptions.PrintGraphHost, host);
569 extra.put(DebugOptions.PrintBinaryGraphPort, port);
570 OptionValues compileOptions = new OptionValues(getOptions(), extra);
571 compiler.compileMethod(new HotSpotCompilationRequest(hotSpotMethod, -1, 0L), false, compileOptions);
572 }
573
574 public Object invokeManagementAction(String actionName, Object[] params) throws Exception {
575 if ("dumpMethod".equals(actionName)) {
576 if (params.length != 0 && params[0] instanceof HotSpotResolvedJavaMethod) {
577 HotSpotResolvedJavaMethod method = param(params, 0, "method", HotSpotResolvedJavaMethod.class, null);
578 String filter = param(params, 1, "filter", String.class, ":3");
579 String host = param(params, 2, "host", String.class, "localhost");
580 Number port = param(params, 3, "port", Number.class, 4445);
581 dumpMethod(method, filter, host, port.intValue());
582 } else {
583 String className = param(params, 0, "className", String.class, null);
584 String methodName = param(params, 1, "methodName", String.class, null);
585 String filter = param(params, 2, "filter", String.class, ":3");
586 String host = param(params, 3, "host", String.class, "localhost");
587 Number port = param(params, 4, "port", Number.class, 4445);
588 dumpMethod(className, methodName, filter, host, port.intValue());
589 }
590 }
591 return null;
592 }
593
594 private static <T> T param(Object[] arr, int index, String name, Class<T> type, T defaultValue) {
595 Object value = arr.length > index ? arr[index] : null;
596 if (value == null || (value instanceof String && ((String) value).isEmpty())) {
597 if (defaultValue == null) {
598 throw new IllegalArgumentException(name + " must be specified");
599 }
600 value = defaultValue;
601 }
602 if (type.isInstance(value)) {
603 return type.cast(value);
604 }
605 throw new IllegalArgumentException("Expecting " + type.getName() + " for " + name + " but was " + value);
606 }
607 }