List进行remove和add操作时缘何会报UnsupportedOperationException

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看段简单的代码:

String[] arry={"abc","eee","fff"};List<String> list= Arrays.asList(arry);list.add("eeef");

运行结果:

Exception in thread "main" java.lang.UnsupportedOperationExceptionat java.util.AbstractList.add(Unknown Source)at java.util.AbstractList.add(Unknown Source)at com.jd.etms.vrs.ws.test.TestList.main(TestList.java:17)at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)at java.lang.reflect.Method.invoke(Unknown Source)at com.intellij.rt.execution.application.AppMain.main(AppMain.java:120)

原因是:使用Arrays.asList转换过来的集合是固定长度的,不能进行remove和add

解决办法:

 List<String> list= new ArrayList<String>(Arrays.asList(arry));

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