java - 问题arrayList类

Question

我在列出 ArrayList 时遇到问题。我的代码:

Iterator<String> iterator = (Iterator<String>) myList.iterator();
while (iterator.hasNext()) {//List tagListAux
        System.out.println("Test -> "+iterator.next());
        if(iterator.next().equalsIgnoreCase(myString)){
        flag = true;
}

 myList.add(myString);

我遇到的异常:

java.util.NoSuchElementException
    at java.util.AbstractList$Itr.next(AbstractList.java:350)
    at myFileinJava(myFileinJava.java:148) 
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
    at java.lang.reflect.Method.invoke(Method.java:597)
    at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:44)
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:15)
    at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:41)
    at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:20)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:76)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:50)
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:193)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:52)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:191)
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:42)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:184)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:236)
    at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:49)
    at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)

我做错了什么？？在我也遇到并发问题之前，通过更改迭代器声明解决了这些问题。
提前致谢

Answer 1

在检查是否存在下一个元素后，您在 while block 中调用 next() 两次 [注意不是两个]

替换

Iterator<String> iterator = (Iterator<String>) myList.iterator();
while (iterator.hasNext()) {//List tagListAux
        System.out.println("Test -> "+iterator.next());
        if(iterator.next().equalsIgnoreCase(myString)){
        flag = true;
}  

与

for(String str: myList){
        System.out.println("Test -> "+str);
        if(str.equalsIgnoreCase(myString)){
        flag = true;
}