com.google.common.base.Platform Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of guava Show documentation
Show all versions of guava Show documentation
Guava is a suite of core and expanded libraries that include
utility classes, google's collections, io classes, and much
much more.
/*
* 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.Locale;
import java.util.ServiceConfigurationError;
import java.util.logging.Level;
import java.util.logging.Logger;
import java.util.regex.Pattern;
import javax.annotation.CheckForNull;
/**
* Methods factored out so that they can be emulated differently in GWT.
*
* @author Jesse Wilson
*/
@GwtCompatible(emulated = true)
@ElementTypesAreNonnullByDefault
final class Platform {
private static final Logger logger = Logger.getLogger(Platform.class.getName());
private static final PatternCompiler patternCompiler = loadPatternCompiler();
private Platform() {}
static CharMatcher precomputeCharMatcher(CharMatcher matcher) {
return matcher.precomputedInternal();
}
static > Optional getEnumIfPresent(Class enumClass, String value) {
WeakReference extends Enum>> 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(@CheckForNull String string) {
return string == null || string.isEmpty();
}
/**
* Returns the string if it is not null, or an empty string otherwise.
*
* @param string the string to test and possibly return
* @return {@code string} if it is not null; {@code ""} otherwise
*/
static String nullToEmpty(@CheckForNull String string) {
return (string == null) ? "" : string;
}
/**
* Returns the string if it is not empty, or a null string otherwise.
*
* @param string the string to test and possibly return
* @return {@code string} if it is not empty; {@code null} otherwise
*/
@CheckForNull
static String emptyToNull(@CheckForNull String string) {
return stringIsNullOrEmpty(string) ? null : string;
}
static CommonPattern compilePattern(String pattern) {
Preconditions.checkNotNull(pattern);
return patternCompiler.compile(pattern);
}
static boolean patternCompilerIsPcreLike() {
return patternCompiler.isPcreLike();
}
private static PatternCompiler loadPatternCompiler() {
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));
}
@Override
public boolean isPcreLike() {
return true;
}
}
static void checkGwtRpcEnabled() {
String propertyName = "guava.gwt.emergency_reenable_rpc";
if (!Boolean.parseBoolean(System.getProperty(propertyName, "false"))) {
throw new UnsupportedOperationException(
Strings.lenientFormat(
"We are removing GWT-RPC support for Guava types. You can temporarily reenable"
+ " support by setting the system property %s to true. For more about system"
+ " properties, see %s. For more about Guava's GWT-RPC support, see %s.",
propertyName,
"https://stackoverflow.com/q/5189914/28465",
"https://groups.google.com/d/msg/guava-announce/zHZTFg7YF3o/rQNnwdHeEwAJ"));
}
logger.log(
java.util.logging.Level.WARNING,
"Later in 2020, we will remove GWT-RPC support for Guava types. You are seeing this"
+ " warning because you are sending a Guava type over GWT-RPC, which will break. You"
+ " can identify which type by looking at the class name in the attached stack trace.",
new Throwable());
}
}