2018-08-31XML文件+DTD约束文件+Schema约束文件

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE web-app SYSTEM "web-app_2_3.dtd">
<web-app>
<servlet>
<servlet-name>HelloServlet</servlet-name>
<servlet-class>com.oracle.homework.HelloServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>HelloServlet</servlet-name>
<url-pattern>/HelloServlet</url-pattern>
</servlet-mapping>
<welcome-file-list>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>
</web-app>


<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://www.example.org/web-app_2_5" 
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.example.org/web-app_2_5 web-app_2_5.xsd"
version="2.5">
<servlet>
<servlet-name>TestServlet</servlet-name>
<servlet-class>com.oracle.homework.TestServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>TestServlet</servlet-name>
<url-pattern>/TestServlet</url-pattern>
</servlet-mapping>
<welcome-file-list>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>
</web-app>


package com.oracle.homework;
import java.util.List;
import org.dom4j.Document;
import org.dom4j.DocumentException;
import org.dom4j.Element;
import org.dom4j.io.SAXReader;
public class TestQues3 {
    public static void main(String[] args) throws DocumentException {
        //获取解析器：
        SAXReader saxr=new SAXReader();
        //获取Document文档：
        Document doc=saxr.read("src/com/oracle/homework/WebXSD.xml");
        //获取文档中的根标签，拿到web-app：
        Element rootEle=doc.getRootElement();
        //获取跟标签的子标签放进List集合：
        List<Element> childEle=rootEle.elements();
        //遍历该集合：
        for(Element ele:childEle){
            if("servlet".equals(ele.getName())){
                System.out.println(ele.element("servlet-name").getName());
                System.out.println(ele.element("servlet-class").getName());
            }else if("servlet-mapping".equals(ele.getName())){
                System.out.println(ele.element("servlet-name").getName());
                System.out.println(ele.element("url-pattern").getName());
            }
            System.out.println(ele.getName());
        }
    }
}


//定义接口：
package com.oracle.homework;
public interface MyServlet {
    public void init();
    public void service();
    public void distory();
}

//实现以上接口：
package com.oracle.homework;
public class MyServletImp implements MyServlet {
    @Override
    public void init() {
        System.out.println("这是Init");
    }

    @Override
    public void service() {
        System.out.println("这是Service");
    }

    @Override
    public void distory() {
        System.out.println("这是Distory");
    }
}

//进行不可描述的操作：
package com.oracle.homework;
import java.util.List;
import org.dom4j.Document;
import org.dom4j.DocumentException;
import org.dom4j.Element;
import org.dom4j.io.SAXReader;
public class TestMyServlet {
    public static void main(String[] args) throws DocumentException,ClassNotFoundException,InstantiationException,IllegalAccessException {
        //获取解析器：
        SAXReader saxr=new SAXReader();
        //获取Document文档：
        Document doc=saxr.read("src/com/oracle/homework/MyServletXSD.xml");
        //获取根标签web-app：
        Element rootEle=doc.getRootElement();
        //获取rootEle的子元素并放进List集合：
        List<Element> childEle=rootEle.elements();
        //定义String接收，并遍历赋值：
        String getPackClass=null;
        for(Element ele:childEle){
            if("servlet".equals(ele.getName())){
                getPackClass=ele.element("servlet-class").getText();
            }
        }
        //获取字节码文件对象：
        Class cla=Class.forName(getPackClass);
        //获取Object对象：
        MyServletImp myser=(MyServletImp)cla.newInstance();
        myser.init();
        myser.service();
        myser.distory();
    }
}