其实不打算写的，因为和前面的是一样的，不过既然有人问起，我就写一下吧。
MyBeanUtils
这是核心的类：
通过这个类来返回一个bean对象的。
你给的参数是bean的class和封装的Map对象。
package cn.hncu.beanUtils; import java.lang.reflect.Field; import java.lang.reflect.InvocationTargetException; import java.lang.reflect.Method; import java.util.Map; /** * @author 陈浩翔 * * 2016-8-25 */ public class MyBeanUtils { public static<T> T populate(Class<T> cls ,Map<String, Object> map) throws InstantiationException, IllegalAccessException, IllegalArgumentException, InvocationTargetException, NoSuchMethodException, SecurityException{ T obj = null; //1、用类反射new出对象 obj = cls.newInstance(); //2 再用类反射对新new的对象设置属性值(必须遵守Java设置规范)--即通过setter方法设置 //2.1遍历出所有该类声明的属性 Field flds[] = cls.getDeclaredFields();//getDeclaredFields()返回Class中所有的字段，包括私有字段； for(Field fld:flds){ //获取该fld对象所代表的属性名 String fldName = fld.getName(); //根据属性名，到map中去读取数据，只有数据非空才需要给该属性设置值 Object value = map.get(fldName); if(value==null){//如果map中不存在对应的属性数据，我们在这里给出提示信息 System.out.println(fldName+"的数据为空"); }else{ //如果map中存在对应的属性数据，则由属性名得出它的setter方法的名字 String mothodName = "set"+fldName.substring(0, 1).toUpperCase()+fldName.substring(1); //根据方法名和参数的数据类型(其实就是属性的类型)，获得Method对象 Class<?> paramTypes[] = new Class[1]; paramTypes[0] = fld.getType(); Method method = cls.getDeclaredMethod(mothodName, paramTypes); //调用该method对象所代表的方法 Object args[] = new Object[1]; args[0]=value; method.invoke(obj, args); } } return obj; } }
Address
package cn.hncu.domain; /** * @author 陈浩翔 * * 2016-8-25 */ public class Address { private String province;//省份 private String city;//城市 public Address() { } public Address(String province, String city) { this.province = province; this.city = city; } public String getProvince() { return province; } public void setProvince(String province) { this.province = province; } public String getCity() { return city; } public void setCity(String city) { this.city = city; } @Override public String toString() { return "Address [province=" + province + ", city=" + city + "]"; } }
Person
package cn.hncu.domain; import java.util.List; import java.util.Map; /** * @author 陈浩翔 * * 2016-8-25 */ public class Person { private String name; private int age; private Address address; private List lists; private Map map; public Person() { super(); } public Person(String name, int age, Address address, List lists, Map map) { super(); this.name = name; this.age = age; this.address = address; this.lists = lists; this.map = map; } public String getName() { return name; } public void setName(String name) { this.name = name; } public int getAge() { return age; } public void setAge(int age) { this.age = age; } public Address getAddress() { return address; } public void setAddress(Address address) { this.address = address; } public List getLists() { return lists; } public void setLists(List lists) { this.lists = lists; } public Map getMap() { return map; } public void setMap(Map map) { this.map = map; } @Override public String toString() { return "Person [name=" + name + ", age=" + age + ", address=" + address + ", lists=" + lists + ", map=" + map + "]"; } }
测试方法:
@Test @SuppressWarnings({ "rawtypes", "unchecked" }) public void test2() { Map<String, Object> p = new HashMap(); p.put("name", "Jack"); p.put("age", 100); p.put("address", new Address("湖南", "长沙")); List lists = new ArrayList(); lists.add(new Book("B001", "红楼梦", 25.00, 53.23, 500)); lists.add(new User("U001", "李四", 25)); lists.add("嵌套使用"); p.put("lists", lists); Map map = new HashMap(); map.put("user", new User("MU002", "MapUser", 30)); map.put("string", "map中的字符串"); p.put("map", map); try { Person person = MyBeanUtils.populate(Person.class, p); System.out.println(person); } catch (ReflectiveOperationException e) { e.printStackTrace(); } }
里面的Book和User类也就是一个bean对象而已。
其实全部可以写空参构造的，我为了方便，就多写了有值的构造方法了。
输出结果:
Person [name=Jack, age=100, address=Address [province=湖南, city=长沙], lists=[Book [uuid=B001, name=红楼梦, inPrice=25.0, outPrice=53.23, num=500], User [uuid=U001, name=李四, age=25], 嵌套使用], map={string=map中的字符串, user=User [uuid=MU002, name=MapUser, age=30]}]
其实和普通的使用没有什么不同的。
无非是外面再嵌套一层罢了~
