java-8

问题 In my Spring JPA Project, I have a repo file as such: @Repository public interface StudentRepository extends JpaRepository<Student, Integer>{ @Query(value = "select * from students", nativeQuery = true) public List<Student> findStudents( @Param("keyword") String keyword ); } With this, I can still copy paste the SQL and run in my DB software. But when it comes to large queries as such: @Query(value = "SELECT\n" + "*\n" + "FROM\n" + "students\n" + "WHERE\n" + "(\n" + "`id` LIKE CONCAT('%',

问题 I have list of objects. Assuming the structure of object is as follows. class Test { Int id; String y; } A 'testList' has four instances of Test class which are t1, t2, t3, t4. Requirement is the if multiple instances has the same value for field 'y', they all should be removed from the list. Duplicate values is considered as error scenario and those instances are dealt separately. For instance in the above case if instance t3 and t4 has same value for 'y' field the processed list should only

问题 I have list of objects. Assuming the structure of object is as follows. class Test { Int id; String y; } A 'testList' has four instances of Test class which are t1, t2, t3, t4. Requirement is the if multiple instances has the same value for field 'y', they all should be removed from the list. Duplicate values is considered as error scenario and those instances are dealt separately. For instance in the above case if instance t3 and t4 has same value for 'y' field the processed list should only

问题 My Web application, which runs in Apache Tomcat/8.0.21, with JVM 1.8.0_45-b15 and Windows Server 2012 on a 16-core (32- with HT) Dual-Xeon NUMA machine, can get stuck, in some very unfortunate circumstances, when the actions described in the title occur at the same time in two different threads. The thread doing the first action ( getStackTrace() ) is trying to perform some diagnostic to detect which part of the system is slowing things down and gets stuck while calling Thread.dumpThreads .

问题 My Web application, which runs in Apache Tomcat/8.0.21, with JVM 1.8.0_45-b15 and Windows Server 2012 on a 16-core (32- with HT) Dual-Xeon NUMA machine, can get stuck, in some very unfortunate circumstances, when the actions described in the title occur at the same time in two different threads. The thread doing the first action ( getStackTrace() ) is trying to perform some diagnostic to detect which part of the system is slowing things down and gets stuck while calling Thread.dumpThreads .

问题 My Web application, which runs in Apache Tomcat/8.0.21, with JVM 1.8.0_45-b15 and Windows Server 2012 on a 16-core (32- with HT) Dual-Xeon NUMA machine, can get stuck, in some very unfortunate circumstances, when the actions described in the title occur at the same time in two different threads. The thread doing the first action ( getStackTrace() ) is trying to perform some diagnostic to detect which part of the system is slowing things down and gets stuck while calling Thread.dumpThreads .

问题 We have an application that was fully working in staging but when we deploy it on production we are getting MQ error 2495. We are running the application in a Tomcat 8.5 and we are using the same MQ libraries (8.0.0.6). The server OS is Windows. The code for reading the message from the MQ looks like: MQEnvironment.hostname = queueSettings.getServer(); MQEnvironment.channel = queueSettings.getChannel(); MQEnvironment.port = queueSettings.getPort(); MQQueueManager queueManager = new

问题 Currently I have list of object array from that array i have to Iterate and add to the list of my LatestNewsDTO what i have done below code working but still i am not satisfy with my way . Is their any efficient way please let me know. Thanks List<Object[]> latestNewses = latestNewsService.getTopNRecords(companyId, false, 3); List<LatestNewsDTO> latestNewsList = new ArrayList(); latestNewses.forEach(objects -> { LatestNewsDTO latestNews = new LatestNewsDTO(); latestNews.setId(((BigInteger)

问题 Currently I have list of object array from that array i have to Iterate and add to the list of my LatestNewsDTO what i have done below code working but still i am not satisfy with my way . Is their any efficient way please let me know. Thanks List<Object[]> latestNewses = latestNewsService.getTopNRecords(companyId, false, 3); List<LatestNewsDTO> latestNewsList = new ArrayList(); latestNewses.forEach(objects -> { LatestNewsDTO latestNews = new LatestNewsDTO(); latestNews.setId(((BigInteger)

问题 Experimenting with streams I ran into the following behavior which I don't quite understand. I created a parallel stream from an iterator and I noticed that it did not seem to be exhibiting parallelism. In the below example I've printed a counter to the console for two parallel streams, one created from an iterator and the other from a list. The stream created from the list exhibited the behavior I expected which was to print the counter in non-sequential order but the stream created from the