设置多种数据类型，级联对象实例化，级联属性赋值

 

一个简单java类中的属性类型不仅仅只有string，还会包含有整数、浮点数、日期等，本课程主要讲解如何实现多种数据类型的赋值以及转换处理操作。
一个类可以与其它类发生引用关系，以描述彼此之间的关系，这样的级联结构中就需要考虑对象实例化问题，本课程主要讲解如何在多级vo配置关系时如何通过反射技术实现动态实例化对象操作。
类引用定义之后就会存在有其它引用类型的属性赋值操作，本课程主要讲解多级实例化对象属性内容的获取与其属性设置。

  1 package com.twitter.demo;
  2 
  3 import java.util.date;
  4 import java.lang.reflect.field;
  5 import java.lang.reflect.method;
  6 import java.text.parseexception;
  7 import java.text.simpledateformat;
  8 
  9 class company{
 10     private string name;
 11     private date createdate;
 12     public string getname() {
 13         return this.name;
 14     }
 15     public void setname(string name) {
 16         this.name = name;
 17     }
 18     public date getcreatedate() {
 19         return this.createdate;
 20     }
 21     public void setcreatedate(date createdate) {
 22         this.createdate = createdate;
 23     }
 24 }
 25 
 26 class dept{
 27     private string dname;
 28     private string loc;
 29     private company company;
 30     public string getdname() {
 31         return dname;
 32     }
 33     public void setdname(string dname) {
 34         this.dname = dname;
 35     }
 36     public string getloc() {
 37         return loc;
 38     }
 39     public void setloc(string loc) {
 40         this.loc = loc;
 41     }
 42     public company getcompany() {
 43         return company;
 44     }
 45     public void setcompany(company company) {
 46         this.company = company;
 47     }
 48 }
 49 
 50 class emp{
 51     private string ename;
 52     private string job;
 53     private double salary;
 54     private integer age;
 55     private date hiredate;
 56     private dept dept;
 57     public string getename() {
 58         return ename;
 59     }
 60     public void setename(string ename) {
 61         this.ename = ename;
 62     }
 63     public string getjob() {
 64         return job;
 65     }
 66     public void setjob(string job) {
 67         this.job = job;
 68     }
 69     public double getsalary() {
 70         return salary;
 71     }
 72     public void setsalary(double salary) {
 73         this.salary = salary;
 74     }
 75     public integer getage() {
 76         return age;
 77     }
 78     public void setage(integer age) {
 79         this.age = age;
 80     }
 81     public date gethiredate() {
 82         return hiredate;
 83     }
 84     public void sethiredate(date hiredate) {
 85         this.hiredate = hiredate;
 86     }
 87     public dept getdept() {
 88         return dept;
 89     }
 90     public void setdept(dept dept) {
 91         this.dept = dept;
 92     }
 93 }
 94 
 95 class beanutils{
 96     private beanutils() {}
 97     public static void setvalue(object obj,string value) {
 98         string results[] = value.split("\\|");
 99         for(int x=0;x<results.length;x++) {
100             string attval[] = results[x].split(":");
101             try {
102                 if(attval[0].contains(".")) {
103                     string temp[] = attval[0].split("\\.");
104                     object currentobject = obj;
105                     for(int y=0;y<temp.length-1;y++) {
106                         method getmethod = currentobject.getclass().getdeclaredmethod("get" + stringutils.initcap(temp[y]));
107                         object tempobject = getmethod.invoke(currentobject);
108                         if(tempobject == null) {
109                             field field = currentobject.getclass().getdeclaredfield(temp[y]);
110                             method method = currentobject.getclass().getdeclaredmethod("set"+stringutils.initcap(temp[y]), field.gettype());
111                             object newobject = field.gettype().getdeclaredconstructor().newinstance();
112                             method.invoke(currentobject, newobject);
113                             currentobject = newobject;
114                         }else {
115                             currentobject = tempobject;
116                         }
117                     }
118                 }else {
119                     field field = obj.getclass().getdeclaredfield(attval[0]);
120                     method setmethod = obj.getclass().getdeclaredmethod("set"+stringutils.initcap(attval[0]), field.gettype());
121                     object convertvalue = beanutils.convertatributevalue(field.gettype().getname(), attval[1]);
122                     setmethod.invoke(obj, convertvalue);
123                 }
124             } catch (exception e) {
125                 // todo: handle exception
126             }
127         }
128     }
129     
130     private static object convertatributevalue(string type,string value) {
131         if("long".equals(type)||"java.lang.long".equals(type)) {
132             return long.parselong(value);
133         }else if ("int".equals(type)||"java.lang.integer".equals(type)) {
134             return integer.parseint(value);
135         }else if ("double".equals(type)||"java.lang.double".equals(type)) {
136             return double.parsedouble(value);
137         }else if ("java.util.date".equals(type)) {
138             simpledateformat sdf = null;
139             if(value.matches("\\d{4}-\\d{2}-\\d{2}")) {
140                 sdf = new simpledateformat("yyyy-mm-dd");
141             }else if (value.matches("\\d{4}-\\d{2}-\\d{2} \\d{2}-\\d{2}-\\d{2}")) {
142                 sdf = new simpledateformat("yyyy-mm-dd hh:mm:ss");
143             }else {
144                 return new date();
145             }
146             try {
147                 return sdf.parse(type);
148             } catch (parseexception e) {
149                 return new date();
150             }
151         }else {
152             return value;
153         }
154     }
155 }
156 
157 class stringutils{
158     public static string initcap(string str) {
159         if(str == null || "".equals(str)) {
160             return str;
161         }
162         if(str.length() == 1) {
163             return str.touppercase();
164         }else {
165             return str.substring(0,1).touppercase()+str.substring(1);
166         }
167     }
168 }
169 
170 class classinstancefactory{
171     private classinstancefactory() {}
172     public static <t> t create(class<?> clazz,string value) {
173         try {
174             object obj = clazz.getdeclaredconstructor().newinstance();
175             beanutils.setvalue(obj, value);
176             return (t) obj;
177         } catch (exception e) {
178             return null;
179         }
180         
181     }
182 }
183 
184 public class javareflectdemo {
185     public static void main(string[] args) throws exception{
186         string value = "ename:smith|job:clerk|salary:8960.00|age:30|hiredate:2003-10-03|"
187                 +"dept.dname:财务部|dept.company.name:twitter|"
188                 +"dept.company.createdate:2001-11-11";
189         emp emp = classinstancefactory.create(emp.class, value);
190         system.out.println(emp);
191         system.out.println(emp.getdept());
192         system.out.println(emp.getdept().getcompany());
193     }
194 }