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This artifact provides a single jar that contains all classes required to use remote Jakarta Enterprise Beans and Jakarta Messaging, including all dependencies. It is intended for use by those not using maven, maven users should just import the Jakarta Enterprise Beans and Jakarta Messaging BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up with different versions on classes on the class path).

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/*
 * Copyright (C) 2009 The Guava Authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
 * in compliance with the License. You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software distributed under the License
 * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
 * or implied. See the License for the specific language governing permissions and limitations under
 * the License.
 */

package com.google.common.base;

import com.google.common.annotations.GwtCompatible;
import java.lang.ref.WeakReference;
import java.util.Iterator;
import java.util.Locale;
import java.util.ServiceConfigurationError;
import java.util.ServiceLoader;
import java.util.logging.Level;
import java.util.logging.Logger;
import java.util.regex.Pattern;
import org.checkerframework.checker.nullness.compatqual.NullableDecl;

/**
 * Methods factored out so that they can be emulated differently in GWT.
 *
 * @author Jesse Wilson
 */
@GwtCompatible(emulated = true)
final class Platform {
  private static final Logger logger = Logger.getLogger(Platform.class.getName());
  private static final PatternCompiler patternCompiler = loadPatternCompiler();

  private Platform() {}

  /** Calls {@link System#nanoTime()}. */
  static long systemNanoTime() {
    return System.nanoTime();
  }

  static CharMatcher precomputeCharMatcher(CharMatcher matcher) {
    return matcher.precomputedInternal();
  }

  static > Optional getEnumIfPresent(Class enumClass, String value) {
    WeakReference> ref = Enums.getEnumConstants(enumClass).get(value);
    return ref == null ? Optional.absent() : Optional.of(enumClass.cast(ref.get()));
  }

  static String formatCompact4Digits(double value) {
    return String.format(Locale.ROOT, "%.4g", value);
  }

  static boolean stringIsNullOrEmpty(@NullableDecl String string) {
    return string == null || string.isEmpty();
  }

  static String nullToEmpty(@NullableDecl String string) {
    return (string == null) ? "" : string;
  }

  static String emptyToNull(@NullableDecl String string) {
    return stringIsNullOrEmpty(string) ? null : string;
  }

  static CommonPattern compilePattern(String pattern) {
    Preconditions.checkNotNull(pattern);
    return patternCompiler.compile(pattern);
  }

  static boolean usingJdkPatternCompiler() {
    return patternCompiler instanceof JdkPatternCompiler;
  }

  private static PatternCompiler loadPatternCompiler() {
    ServiceLoader loader = ServiceLoader.load(PatternCompiler.class);
    // Returns the first PatternCompiler that loads successfully.
    try {
      for (Iterator it = loader.iterator(); it.hasNext(); ) {
        try {
          return it.next();
        } catch (ServiceConfigurationError e) {
          logPatternCompilerError(e);
        }
      }
    } catch (ServiceConfigurationError e) { // from hasNext()
      logPatternCompilerError(e);
    }
    // Fall back to the JDK regex library.
    return new JdkPatternCompiler();
  }

  private static void logPatternCompilerError(ServiceConfigurationError e) {
    logger.log(Level.WARNING, "Error loading regex compiler, falling back to next option", e);
  }

  private static final class JdkPatternCompiler implements PatternCompiler {
    @Override
    public CommonPattern compile(String pattern) {
      return new JdkPattern(Pattern.compile(pattern));
    }
  }
}