问题：

将集合通过toArray转为Object[]数组后，再通过向下转型失败

源代码：

public void test(){
        List<String> list = new ArrayList<String>();
        list.add("a");
        list.add("b");
        list.add("c");
        String[] strings = (String[]) list.toArray();
        for (String string : strings) {
            System.out.println(string);
        }
 }

错误：

java.lang.ClassCastException: [Ljava.lang.Object; cannot be cast to [Ljava.lang.String;

	at Test14.test(Test14.java:14)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:59)
	at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
	at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:56)
	at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
	at org.junit.runners.ParentRunner$3.evaluate(ParentRunner.java:305)
	at org.junit.runners.BlockJUnit4ClassRunner$1.evaluate(BlockJUnit4ClassRunner.java:100)
	at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:365)
	at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:103)
	at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:63)
	at org.junit.runners.ParentRunner$4.run(ParentRunner.java:330)
	at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:78)
	at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:328)
	at org.junit.runners.ParentRunner.access$100(ParentRunner.java:65)
	at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:292)
	at org.junit.runners.ParentRunner$3.evaluate(ParentRunner.java:305)
	at org.junit.runners.ParentRunner.run(ParentRunner.java:412)
	at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
	at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:68)
	at com.intellij.rt.execution.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:47)
	at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:242)
	at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:70)

解决代码：

    public void test(){
        List<String> list = new ArrayList<String>();
        list.add("a");
        list.add("b");
        list.add("c");
        String[] temp = new String[3];
        String[] strings = list.toArray(temp);
        for (String string : strings) {
            System.out.println(string);
        }
    }