Java Reflection Learning Three

Reflections and Arrays

　　

　　The Java.lang.Array class provides a variety of static methods for dynamically creating and accessing array elements.

The main () method of the ArrayTester1 class creates a string array of length 10, then sets the element with index position 5 to "hello", and then reads the value of the element with index position 5.

　　

Import Java.lang.reflect.array;public class arraytester1{public    static void Main (string[] args) throws exception< c4/>{        class<?> ClassType = Class.forName ("java.lang.String");                Generates an array, specifying the element type and array length of        Object array = array.newinstance (ClassType, ten);                Array.set (Array, 5, "Hello");        String str = (string) array.get (Array, 5);                System.out.println (str);}                    }

Multidimensional arrays

First, distinguish between the following:

System.out.println (integer.type);   System.out.println (Integer.class);

Output:

Int

Class Java.lang.Integer

A program instance of a multidimensional array:

　　

Import Java.lang.reflect.array;public class arraytester2{public static void Main (string[] args) {int[] dims        = new Int[] {5, 10, 15};    Note the following two kinds of System.out.println (integer.type) are differentiated;    int System.out.println (integer.class);        Integer//Create a three-dimensional array, the three dimensions of this array are 5,10,15 Object array = array.newinstance (Integer.type, dims);        Variable parameters can also be written like this://Object array = array.newinstance (Integer.type, 5,10,15);                System.out.println (array instanceof int[][][]);    class<?> CLASSTYPE0 = Array.getclass (). Getcomponenttype ();    Returns the array element type SYSTEM.OUT.PRINTLN (CLASSTYPE0);        The elements of a three-dimensional array are two-dimensional arrays, Output: class [I//Get an array of index 3 for the first layer, and return a two-dimensional array of Object Arrayobject = Array.get (array, 3);    class<?> ClassType = Arrayobject.getclass (). Getcomponenttype ();    Returns the array element type SYSTEM.OUT.PRINTLN (ClassType); The elements of a two-dimensional array are one-dimensional arrays, and the output: class [I//) returns a one-dimensional array arrayobject = Array.get (Arrayobject, 5);    class<?> classType2 = Arrayobject.getclass (). Getcomponenttype ();    Returns the array element type SYSTEM.OUT.PRINTLN (CLASSTYPE2);        The elements of a one-dimensional array are int//The position of a one-dimensional array labeled 10 is set at the value of Array.setint (Arrayobject, 10, 37);        Int[][][] Arraycast = (int[][][]) array;    System.out.println (arraycast[3][5][10]); }}

Resources:

Http://www.cnblogs.com/mengdd/archive/2013/01/26/2878136.html

Http://www.cnblogs.com/gulvzhe/archive/2012/01/27/2330001.html

Http://www.cnblogs.com/rollenholt/archive/2011/09/02/2163758.html

Http://www.cnblogs.com/octobershiner/archive/2012/03/18/2404751.html

Java Reflection Learning Three