Simple Way to find the occurrence of string value in an array using Java 8 features. public void checkDuplicateOccurance() { List<String> duplicateList = new ArrayList<String>(); duplicateList.add("Cat"); duplicateList.add("Dog"); duplicateList.add("Cat"); duplicateList.add("cow"...
Exception in thread "main"java.util.ConcurrentModificationException at java.util.ArrayList$Itr.checkForComodification(ArrayList.java:909) at java.util.ArrayList$Itr.next(ArrayList.java:859) at com.design.mode.Test2.main(Test2.java:15) 符合注释上的说明,既然说是由迭代器使用,那再看看迭代器代码(删...
关于wordcount,首先,一开始的构思是先读取文件,一段时间没有使用java,对io流的相关内容不是很熟悉,成功将文件存进ArrayList中后我没有考虑到Array List变量之间的赋值问题,直接用=去赋值,发现取出的数据出错,经过上网搜索了解了关于ArrayList对象之间赋值该注意的问题,收获不少。其次,对输入指令格式的验证问题,由于之前...
如果抛出异常,就类似这个样子: 0 1Exception in thread "Thread-0"java.util.ConcurrentModificationExceptionat java.util.ArrayList$Itr.checkForComodification(ArrayList.java:909) at java.util.ArrayList$Itr.next(ArrayList.java:859) at com.rw.importword.utils.Text$1.run(Text.java:19) at java.lang.Thr...
这个就没什么好说的了,ArrayList、LinkedList、HashMap等都是线程非安全的类,点击这里了解为什么不安全。 8、Java中如何获取到线程dump文件 死循环、死锁、阻塞、页面打开慢等问题,打线程dump是最好的解决问题的途径。所谓线程dump也就是线程堆栈,获取到线程堆栈有两步: ...
packagecom.countdownlatch;importjava.util.ArrayList;importjava.util.List;importjava.util.concurrent.CountDownLatch;importjava.util.concurrent.Executor;importjava.util.concurrent.Executors;importjava.util.concurrent.TimeUnit;/** * 系统启动器 * * @author Administrator ...
publicclassModel{privateString name;privateString status;privatelongtotal;privatelonginProgressCount;privatelongcompletedCount;privatelongcancelCount;staticclassModelBuilder{privatelongtotal;privatelonginProgressCount;privatelongcompletedCount;privatelongcancelCount;publicModelBuildersetTotal(longtotal){this.total = to...
public static void main(String[] args) { // 下载文件总数 List<Integer> resultList = new ArrayList<>(100); IntStream.range(0,100).forEach(resultList::add); // 下载文件分段 List<List<Integer>> split = CollUtil.split(resultList, 10); ExecutorService executorService = BaseThreadPoolExector....
Exceptioninthread"main"java.util.concurrent.RejectedExecutionException: Task java.util.concurrent.FutureTask@300ffa5d rejected from java.util.concurrent.ThreadPoolExecutor@1f17ae12[Running, pool size = 2, active threads = 2, queued tasks = 1, completed tasks = 0] ...
即传入一个Specification对象,即可完成条件查询,来看一个简单的例子。MySpecification就是封装好的工具类,能够大幅简化jpa构建条件查询的操作。 代码语言:javascript 复制 privatePage<PtActivity>find(String states,String name,String begin,String end,Pageable pageable){MySpecification<PtActivity>mySpecification=newMySpe...