persistence

问题 Considering an Apache Flink streaming-application with a pipeline like this: Kafka-Source -> flatMap 1 -> flatMap 2 -> flatMap 3 -> Kafka-Sink where every flatMap function is a non-stateful operator (e.g. the normal .flatMap function of a Datastream ). How do checkpoints/savepoints work, in case an incoming message will be pending at flatMap 3 ? Will the message be reprocessed after restart beginning from flatMap 1 or will it skip to flatMap 3 ? I am a bit confused, because the documentation

问题 how to make data structures(like trees, graphs ) persistent in c++? 回答1: Try Google Protocol Buffers or the Boost serialization library. 回答2: In general, you will need to serialise the structure so that you can write it to a file or a database. If you have a custom structure, then you will need to write the method to serialise and deserialise (i.e. write out and read in the structure). Otherwise, if you have used a structure from a library, there may already be (de)serialisation methods. eg.

问题 I'm developing a GWT application in Eclipse on JBoss AS7. However, when I try to deploy, I get this 13:11:52,546 ERROR [org.jboss.msc.service.fail] (MSC service thread 1-1) MSC00001: Failed to start service jboss.persistenceunit."ctivTools_GWT.war#Catalog": org.jboss.msc.service.StartException in service jboss.persistenceunit."ctivTools_GWT.war#Catalog": Failed to start service at org.jboss.msc.service.ServiceControllerImpl$StartTask.run(ServiceControllerImpl.java:1767) [jboss-msc-1.0.2.GA

问题 Hello guys and Happy new year to all! I'm having a weird trouble in my app which I can't seem to fix. It should be a logic error, but I'm not able to somehow catch it. Here is my code public String[] str={"Disabled","Sound Quality Prefered","Bass Prefered","Battery Prefered",}; public int ThemePresetValue = 0; private int SelectedThemePresetValue = 0; public void presets() { AlertDialog.Builder alertDialog = new AlertDialog.Builder(this); alertDialog.setTitle("Select Your Sound Preset");

问题 This question already has answers here : Eclipselink with MongoDB java.lang.ClassCastException (3 answers) Closed 4 years ago . I'm getting stuck in configuring JPA for Mongodb. Here is my stack exception : [EL Config]: connection: 2014-03-31 10:48:24.171--ServerSession(1883377923)--Connection(1001688235)--Thread(Thread[main,5,smarttrade])--disconnect [EL Severe]: ejb: 2014-03-31 10:48:24.181--ServerSession(1883377923)--Thread(Thread[main,5,smarttrade])--java.lang.ClassCastException: org

问题 I am using the official GitLab Docker image. I want to have pre-configured user accounts available in my GitLab container to be used for tests. But user accounts are saved in a volume, so I can't just commit and push the GitLab image after having created my test users. So: how should I persist them? One way would be to create them on startup using the API after each new deployment, but this is quite slow/cumbersome. 回答1: As you said, it's not going to be as easy as committing and pushing a

问题 I want to use entity manager from container, but when I try to access it I get java.lang.IllegalStateException: Need active coordination persistence.xml <persistence-unit name="data-point" transaction-type="JTA"> <jta-data-source>osgi:service/javax.sql.DataSource/(osgi.jndi.service.name=dvdrental)</jta-data-source> <properties> <property name="hibernate.dialect" value="org.hibernate.dialect.PostgreSQL82Dialect"/> <property name="hibernate.show_sql" value="true"/> <property name="hibernate

问题 I'm developing an application using AngularJS & PersistenceJS . I'm getting trouble dealing with Asynchronous calls as the Controller : cars.controller('CrashWidgetOneCtrl',function($scope, $location, $routeParams, CrashServices){ if($routeParams.crashId){ $scope.data = {}; console.log("CrashID: "+$routeParams.crashId); crashId = $routeParams.crashId; alert(1);//Works CrashServices.getCrashDetails($scope, crashId).then(function(result){ console.log(result); alert(2);//Never Fires }); alert(3)

问题 New to python... I have the following class Key, that extends dict: class Key( dict ): def __init__( self ): self = { some dictionary stuff... } def __getstate__(self): state = self.__dict__.copy() return state def __setstate__(self, state): self.__dict__.update( state ) I want to save an instance of the class with its data using pickle.dump and then retrieve the data using pickle.load. I understand that I am supposed to somehow change the getstate and the setstate, however, am not entirely

问题 This sounds like a simple question, but I don't know how to search for its answer. I have a trie implementation in C# that will store about 80K words from a dictionary file. It takes quite a while to load all these words (more than 5 mins). I was wondering, what is the best way to "persist" those data so I don't have to reload all words every time I start the application? Thanks. 回答1: Like all other performance issues, the ideal solution will follow from profiling your current solution and