虽然可以通过dom4j定义属于自己的策略将对象序列到xml文件中,但是thoughtworks公司提供的xstream 包含的功能很强大,一般的功能都涵盖了,而且使用起来也很方便。
一.持久化对象
package com.ysen;
//这是一组简单的类。XStream能把这些类的实例转换到XML或是转换回来。
//注意到这些都是私有变量。XStream不关心变量的作用域。不需要getter或是setter方法。并且,XStream不限定需要默认的构造函数
public class Employee {
private String name;
private String designation;
private String department;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getDesignation() {
return designation;
}
public void setDesignation(String designation) {
this.designation = designation;
}
public String getDepartment() {
return department;
}
public void setDepartment(String department) {
this.department = department;
}
@Override
public String toString() {
return "Name : "+this.name+
"\nDesignation : "+this.designation+
"\nDepartment : "+this.department;
}
}
操作的对象
public class Writer {
public static void main(String[] args) {
Employee e = new Employee();
e.setName("Jack");
e.setDesignation("Manager");
e.setDepartment("Finance");
//Serialize the object
//实例化XStream
//使用XStream,简单实例化XStream类:
XStream xs = new XStream();
// xs.omitField(Employee .class, "name"); //定义某一个属性的值不进行xml序列化。
// xs.useAttributeFor(String.class); // 对所有String类型的字段定义为属性tag显示
// xs.useAttributeFor("name",String.class);// 对所有String类型的字段名成为name 定义为属性tag显示,读取的时候获取不了该值
try {
FileOutputStream fs = new FileOutputStream("d:/employeedata.xml");
xs.toXML(e, fs);
} catch (FileNotFoundException e1) {
e1.printStackTrace();
}
}
}
public class ConfigReader {
String datasourcename = null;
String ipaddress = null;
String logfilename = null;
String appender = null;
@Override
public String toString() {
// This method prints out the values stored in the member variables
return "Datasource Name : "+datasourcename+
" \nIP Address : "+ipaddress+
" \nLogfilename : "+logfilename+
" \nAppender : "+appender;
}
public static void main(String[] args) throws FileNotFoundException {
XStream xs = new XStream(new DomDriver());
FileInputStream fis = new FileInputStream("d:/Config.xml");
//映射将对象属性datasourcename映射到xml别名datasource-name中
xs.aliasField("datasource-name", ConfigReader.class, "datasourcename");
//这是可选的一步。没有这步XStream也可以很好的起作用,但是XML元素的名字就会包含每个类的全称(包括包名),这将会使生成XML稍大。
xs.alias("config", ConfigReader.class);
ConfigReader r = (ConfigReader)xs.fromXML(fis);
System.out.println(r.toString());
}
}
Config.xml
<?xml version="1.0" encoding="UTF-8"?> <config> <datasource-name>IRIS</datasource-name> <ipaddress>9.124.74.85</ipaddress> <logfilename>DailyLogApplication.log</logfilename> <appender>console</appender> </config>
二
public class Author {
private String name;
public Author(String name) {
this.name = name;
}
public String getName() {
return name;
}
}
public class Entry {
private String title, description;
public Entry(String title, String description) {
this.title = title;
this.description = description;
}
}
public class Blog {
private Author writer;
private List entries = new ArrayList();
public Blog(Author writer) {
this.writer = writer;
}
public void add(Entry entry) {
entries.add(entry);
}
public List getContent() {
return entries;
}
public static void main(String[] args) throws FileNotFoundException {
Blog teamBlog = new Blog(new Author("Guilherme Silveira"));
teamBlog.add(new Entry("first","My first blog entry."));
teamBlog.add(new Entry("tutorial","Today we have developed a nice alias tutorial. Tell your friends! NOW!"));
XStream xstream = new XStream(new DomDriver());//不需要XPP3库
//System.out.println(xstream.toXML(teamBlog));
//序列化一个对象到XML
FileOutputStream fs = new FileOutputStream("d:/Blog.xml");
xstream.toXML(teamBlog, fs);
//从XML反序列化一个对象
FileInputStream fis = new FileInputStream("d:/Blog.xml");
//从xml文件中加载对象是需要new XStream(new DomDriver());
Blog blog = (Blog)xstream.fromXML(fis);
System.out.println(blog);
}
}