Guava

问题 I'm programming a web app which uses richfaces 4.3.7 and google guice 4.0. The problem is that richfaces using guava 18 und google guice using guava 16, this results with the following Exception: java.lang.RuntimeException: java.lang.IllegalAccessError: tried to access method com.google.common.collect.MapMaker.makeComputingMap(Lcom/google/common/base/Function;)Ljava/util/concurrent/ConcurrentMap; from class org.richfaces.resource.ResourceLibraryFactoryImpl Caused by: java.lang

问题 I'm programming a web app which uses richfaces 4.3.7 and google guice 4.0. The problem is that richfaces using guava 18 und google guice using guava 16, this results with the following Exception: java.lang.RuntimeException: java.lang.IllegalAccessError: tried to access method com.google.common.collect.MapMaker.makeComputingMap(Lcom/google/common/base/Function;)Ljava/util/concurrent/ConcurrentMap; from class org.richfaces.resource.ResourceLibraryFactoryImpl Caused by: java.lang

问题 I have been experimenting with guava lately and I have not come across a way to copy all of the files from one directory to another. If anyone can point me in the right direction on how to do this that would be great. 回答1: Guava is not providing any fancy file manipulation utilities apart from the rather rudimentary functionality in Files. To copy files from one directories, please use a different library, e.g. commons.io.FileUtils.copyDirectory. 来源： https://stackoverflow.com/questions

问题 I have been experimenting with guava lately and I have not come across a way to copy all of the files from one directory to another. If anyone can point me in the right direction on how to do this that would be great. 回答1: Guava is not providing any fancy file manipulation utilities apart from the rather rudimentary functionality in Files. To copy files from one directories, please use a different library, e.g. commons.io.FileUtils.copyDirectory. 来源： https://stackoverflow.com/questions

问题 We'd find it very useful to have an AddListener to complement RemovalListener in Google Guava. Is there a suitable alternative to an AddListener that would complement RemovalListener ? 回答1: You can provide that yourself - just pass your custom listener to your computing Function , and whenever you compute a value, notify the listener. If you are using asMap().put(..) , then you'd have to wrap the whole thing in in your custom classes that delegate to the originals but also invoke the addition

问题 I have list of strings, where each string consists of letters separated by the character ',' (comma). I want to go through the list of strings, split on comma, and calculate how many times each letter occurs, and store the result in a Multiset. Blank strings should be ignored, and the split parts should be trimmed. The multiset should be sorted on key. The below code works, i.e., it produces the desired Multiset. However, I couldn't figure out how to use the proper collector method (Multisets

问题 So for example: CacheBuilder.newBuilder() .maximumSize(1000) .expireAfterAccess(1, TimeUnit.MINUTES) .expireAfterWrite(1, TimeUnit.MINUTES) .build(new CacheLoader<String, Object>() { @Override public Object load (String key) { return ...; } }); If calling invalidate(key) on the returned instance, a subsequent call to getUnchecked() will ALWAYS use the previous value until at least 1 minute has passed in which cause it will call load(key) again. A call to cleanUp() right after invalidate()

问题 So for example: CacheBuilder.newBuilder() .maximumSize(1000) .expireAfterAccess(1, TimeUnit.MINUTES) .expireAfterWrite(1, TimeUnit.MINUTES) .build(new CacheLoader<String, Object>() { @Override public Object load (String key) { return ...; } }); If calling invalidate(key) on the returned instance, a subsequent call to getUnchecked() will ALWAYS use the previous value until at least 1 minute has passed in which cause it will call load(key) again. A call to cleanUp() right after invalidate()

问题 So I have been using Guava's Optional for a while now, and I moving to Java 8 so I wanted to use it's Optional class, but it doesn't have my favorite method from Guava, asSet(). Is there a way to do this with the Java 8 Optional that I am not seeing. I love being able to treat optional as a collection so I can do this: for( final User u : getUserOptional().asSet() ) { return u.isPermitted(getPermissionRequired()); } In some cases avoids the need for an additional variable. IE Optional<User>

问题 I am having some trouble running a Hadoop job that includes a newer version of Guava than the one that is included in the Hadoop distribution (CDH 5.2). This is a known problem. I try to solve it by shading the libraries using the Maven shade plugin. Therefore, I added the following lines to my pom.xml : <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-shade-plugin</artifactId> <version>2.3</version> <executions> <execution> <phase>package</phase> <goals> <goal>shade<