java使用反射机制进行对象间数据赋值获取

本是古典何须时尚 2022-06-09 03:56 151阅读 0赞

下面是使用的反射的utils   对象的私有属性和公有属性都可以获取到 getDeclaredFields

package com.cn.fs;  
import java.lang.reflect.Field;  
public class FsUtils \{  
public static <T> T copyAttr(Object parameter,Object  reclazz) \{  
Field \[\] fields = parameter.getClass().getDeclaredFields();  
if(null!=fields)\{  
for(int i=0;i<fields.length;i++)\{  
Field pojo = fields\[i\];  
String attrName = pojo.getName();  
Object attrValue = null;  
Field rfield;  
try \{  
pojo.setAccessible(true);  
attrValue = pojo.get(parameter);  
rfield = reclazz.getClass().getDeclaredField(attrName);  
rfield.setAccessible(true);  
rfield.set(reclazz,  attrValue);  
 \} catch (IllegalArgumentException e) \{  
e.printStackTrace();  
\} catch (IllegalAccessException e) \{  
e.printStackTrace();  
\}catch (NoSuchFieldException e) \{  
continue;  
\} catch (SecurityException e) \{  
e.printStackTrace();  
\} \}\}  
return  (T) reclazz;  
\}\}

要进行赋值的PO

package com.cn.fs;  
public class Person \{  
public int age;  
public String name;  
private int pageSize;  
private int pageNum;  
public int getAge() \{  
return age;  
\}  
public void setAge(int age) \{  
this.age = age;  
\}  
public String getName() \{  
return name;  
\}  
public void setName(String name) \{  
this.name = name;  
\}  
public int getPageSize() \{  
return pageSize;  
\}  
public void setPageSize(int pageSize) \{  
this.pageSize = pageSize;  
\}  
public int getPageNum() \{  
return pageNum;  
\}  
public void setPageNum(int pageNum) \{  
this.pageNum = pageNum;  
\}\}

传入包含已经有值的

package com.cn.fs;  
public class PageAbles \{  
private int pageSize;  
private int pageNum;  
private int totalNum;  
public int getPageSize() \{  
return pageSize;  
\}  
public void setPageSize(int pageSize) \{  
this.pageSize = pageSize;  
\}  
public int getPageNum() \{  
return pageNum;  
\}  
public void setPageNum(int pageNum) \{  
this.pageNum = pageNum;  
\}  
public int getTotalNum() \{  
return totalNum;  
\}  
public void setTotalNum(int totalNum) \{  
this.totalNum = totalNum;  
\}\}

测试类

package com.cn.fs;  
public class TestFsDemo \{  
public static void main(String\[\] args) \{  
Person pers = new Person();  
pers.setAge(20);  
pers.setName("zhangsan");  
PageAbles pagePo = new PageAbles();  
pagePo.setPageNum(5);  
pagePo.setPageSize(40);  
pagePo.setTotalNum(200);  
System.out.println(pers.getName()+".........之前..........."+pers.getPageSize()+"...................."+pers.getPageNum());  
pers = FsUtils.copyAttr(pagePo, pers);  
System.out.println(pers.getName()+".........之后..........."+pers.getPageSize()+"...................."+pers.getPageNum());  
 \}  
\}  
 测试结果如下

zhangsan.........之前...........0....................0  
zhangsan.........之后...........40....................5