System.arraycopy方法

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//native方法，将src的数组从索引从srcPos开始，长度为length,复制到dest数组，索引为destPos，长度为lengthpublic static native void arraycopy(Object src,  int  srcPos,                                         Object dest, int destPos,                                         int length);

　

 

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@Test     void contextLoads() {         String[] arr1 = {"a1","a2","a3","a4","a5"};         String[] arr2 = {"b1","b2","b3","b4","b5"};         System.arraycopy(arr1,1,arr2,1,3);         for (String s : arr2) {             System.out.println(s);         }         System.out.println("=======================");         String[] arr3 = {"a1","a2","a3","a4","a5"};         String[] arr4 = new String[5];         System.arraycopy(arr3,1,arr4,1,3);         for (String s : arr4) {             System.out.println(s);         }     }

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