public static String getUpdate(Object obj) throws IllegalArgumentException, IllegalAccessException{

Class<? extends Object>classll=obj.getClass();

String sql="Update "+classll.getSimpleName()+" set ";

String sql2=" ";

String sql3=" where ";

Field[] field=classll.getDeclaredFields();

for(Field f:field){

f.setAccessible(true);

Object value = f.get(obj);

if(f.isAnnotationPresent(PrimaryKey.class)){

if(value instanceof String){

sql3 +=f.getName()+"='"+value+"'";

}else{

sql3 +=f.getName()+"="+value+"";

}

}else if(!f.isAnnotationPresent(NonField.class)){

if(value instanceof String){

sql2 +=f.getName()+"='"+value+"',";

}else{

sql2 +=f.getName()+"="+value+", ";

}

}

}

sql2 = sql2.substring(0,sql2.length()-2);

sql=sql+sql2+sql3;

return sql;

}

 

Userinfo u=new Userinfo();

u.setUsername(" 成都");

u.setUserpwd(" 张山");

u.setUserquan("123");

String userInfoSQL = null;

try {

userInfoSQL = BeanUtil.getUpdate(u);

} catch (SecurityException e) {

// TODO Auto-generated catch block

e.printStackTrace();

} catch (IllegalAccessException e) {

// TODO Auto-generated catch block

e.printStackTrace();

} catch (IllegalArgumentException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

System.out.println(userInfoSQL);

 

 

package com.gxa.bj.util;

import java.lang.annotation.ElementType;

import java.lang.annotation.Retention;

import java.lang.annotation.RetentionPolicy;

import java.lang.annotation.Target;

@Target(ElementType.FIELD)

@Retention(RetentionPolicy.RUNTIME)

public @interface NonField {

}

 

//通过反射区获取相应的类的一些定义

Class classzz=Person.class;

//另外一种获取Class对象的方法

Person p=new Person();

Class classzz2=p.getClass();

System.out.println("类的名称:"+classzz.getSimpleName());

Field[] fields=classzz.getDeclaredFields();//获取定义的字段

for(Field f : fields){

Class c=f.getType();//字段

if(c.getPackage()!=null){

if(c.getPackage().getName().equals("com.gxa.bj.test")){

System.out.println(c.getPackage().getName());

System.out.println("字段类型:"+c.getName());

System.out.println("该字段的名字:"+f.getName());

}

}

}

 

 

public static void main(String[] args) {

// TODO Auto-generated method stub

Person p=new Person();

p.setAge(12);

p.setName(" 张三 ");

Class<? extends Object> classzz = p.getClass();

//通过反射去获取字段的值

Field[] f = classzz.getDeclaredFields();

for(Field field :f){

String methodName="get"+field.getName().substring(0,1).toUpperCase()+field.getName().substring(1);

try {

Method m=classzz.getDeclaredMethod(methodName);

Object o = null;

try {

o = m.invoke(p);

} catch (IllegalAccessException e) {

// TODO Auto-generated catch block

e.printStackTrace();

} catch (IllegalArgumentException e) {

// TODO Auto-generated catch block

e.printStackTrace();

} catch (InvocationTargetException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

if(o!=null){

System.out.println("方法名:"+methodName+",方法值:"+o);

}

} catch (NoSuchMethodException e) {

// TODO Auto-generated catch block

e.printStackTrace();

} catch (SecurityException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

}

}

}