Java Field 反射機制的簡單使用

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Code highlighting produced by Actipro CodeHighlighter (freeware)http://www.CodeHighlighter.com/-->import java.lang.reflect.Field;public class FieldTest {    int i;    public float f;    protected boolean b;    private String s;        public FieldTest()    {        i=0;        f=0.0f;        b = true;        s = "";    }    public static void main(String[] args){        //進行類執行個體化：        FieldTest fieldTest = new FieldTest();        //擷取類的域        Field[] declaredFields = FieldTest.class.getDeclaredFields();        for(int i=0;i<declaredFields.length;i++){            Field field = declaredFields[i];            System.out.println("名稱為："+field.getName());            Class fieldType = field.getType();            System.out.println("類型為："+field.getType());            boolean isTurn = true;            while(isTurn)            {                try{                    isTurn = false;                    System.out.println("修改前的值為："+ field.get(fieldTest));                    if(fieldType.equals(int.class))                    {                        System.out.println("利用setInt()方法修改成員變數的值.");                        field.setInt(fieldTest, 124);                    }                    else if(fieldType.equals(float.class))                    {                        System.out.println("利用setFloat()方法修改成員變數的值.");                        field.setFloat(fieldTest, 9.9f);                    }else if(fieldType.equals(boolean.class))                    {                        System.out.println("利用setBoolean()方法修改成員變數的值.");                        field.setBoolean(fieldTest, false);                    }                    else                    {                        System.out.println("利用set()方法修改成員變數的值.");                        field.set(fieldTest, "NWQ");                    }                    System.out.println("修改後的值為："+field.get(fieldTest));                }catch(Exception e)                {                    System.out.println("在設定成員變數時發生異常,執行setAccessible()方法.");                    //修改可訪問性，如果為true，當前域的所有成員都可以訪問                    field.setAccessible(true);                    isTurn = true;                }            }            System.out.println("**************");        }    }}

Java Field 反射機制的簡單使用