My Java Blog Park

2006年8月3日 #

http学习笔记

一.HTTP请求:
HTTP请求分为:
  1).请求行
  2).消息头
  3).空行
  4).正文

1.请求行
  [方法 URI HTTP版本信息]
  如: GET /index.htm HTTP/1.0

2.方法(全部大写):
  GET      请求URI标识的资源
  HEAD     请求获取响应消息头
  PUT      请求存储资源,并用URI作为其标识
  POST     请求服务器接收信息
  CONNECT  ?
  TRACE   
  DELETE
  OPTIONS


二.HTTP响应:
  1).状态行
  2).消息头
  3).空行
  4).正文(资源的内容,比如index.htm文件的文本内容)


1.状态行
  HTTP版本信息 状态码 响应码描述
  例: HTTP/1.1 200 OK

2.状态码(第一位表示响应的类别)
  1xx:
  2xx:
  3xx:
  4xx:
  5xx:
HTTP协议状态码具体意义
   100  :  Continue
   101  :  witchingProtocols
   200  :  OK
   201  :  Created
   202  :  Accepted
   203  :  Non-AuthoritativeInformation
   204  :  NoContent
   205  :  ResetContent
   206  :  PartialContent
   300  :  MultipleChoices
   301  :  MovedPermanently
   302  :  Found
   303  :  SeeOther
   304  :  NotModified
   305  :  UseProxy
   307  :  TemporaryRedirect
   400  :  BadRequest
   401  :  Unauthorized
   402  :  PaymentRequired
   403  :  Forbidden
   404  :  NotFound
   405  :  MethodNotAllowed
   406  :  NotAcceptable
   407  :  ProxyAuthenticationRequired
   408  :  RequestTime-out
   409  :  Conflict
   410  :  Gone
   411  :  LengthRequired
   412  :  PreconditionFailed
   413  :  RequestEntityTooLarge
   414  :  Request-URITooLarge
   415  :  UnsupportedMediaType
   416  :  Requestedrangenotsatisfiable
   417  :  ExpectationFailed
   500  :  InternalServerError
   501  :  NotImplemented
   502  :  BadGateway
   503  :  ServiceUnavailable
   504  :  GatewayTime-out
   505  :  HTTPVersionnotsupported

三.HTTP消息头:
1. 普通
2. 请求头
3. 响应头
4. 实体头

格式:(名字大小写无关)
<名字>:<空格><值>

1.普通头
  .Cache-Control  (HTTP1.1,  HTTP1.0:Pragma)
      缓存指令:
      请求时: no-cache,no-store,max-age,max-stale,min-fresh,only-if-cached
      响应时: public,private,no-cache,no-store,no-transform,must-revalidate,proxy-revalidate,max-age,s-maxage.
      例: Cache-Control: no-cache
  .Date
      客户端:在发送正文时要包含Date,
      服务器:在响应时包含Date.
  .Connection
  .Pragma(1.0用)

2. 请求头
  .Accept
  .Accept-Charset
  .Accept-Encoding
  .Accept-Language
  .Authorization
  .Host(必须的)
  .User-agent

3.响应头
  .Location
  .Server
  .WWW-Authenticate,要包含在401中.

4.实体头
  .Content-Encoding
  .Content-Language
  .Content-Length
  .Content-Type
  .Last-Modified
  .Expires

 

posted @ 2006-09-28 15:53 2195113 阅读(231) | 评论 (0)编辑 收藏

简单的DOM(java)的操作

package wlz.xml;

import javax.xml.parsers.*;
import org.w3c.dom.*;
//import javax.xml.transform.*;
//import javax.xml.transform.dom.DOMSource;
//import javax.xml.transform.stream.StreamResult;
import java.io.*;
import org.apache.xml.serialize.*;

public class WriteXml {
    public static void writeXml(Document doc,String filename) throws Exception{
        /*TransformerFactory tf=TransformerFactory.newInstance();
        Transformer f=tf.newTransformer();
        //f.setOutputProperties();
        DOMSource source=new DOMSource(doc);
        StreamResult result=new StreamResult(new File(filename));
        f.transform(source,result);*/
        
        FileOutputStream fos = new FileOutputStream(filename);
        OutputFormat of = new OutputFormat("XML","GB2312",true);
        of.setIndent(2);
        of.setIndenting(true);
        XMLSerializer serializer = new XMLSerializer(fos,of);
        
        serializer.asDOMSerializer();
        serializer.serialize(doc.getDocumentElement());
        fos.close();
    }
    
    public static void outputElement(Document doc,String elementName){
        NodeList list= doc.getElementsByTagName(elementName);
        System.out.println("------------------------------------------");
        for(int i=0;i<list.getLength();i++){
            System.out.println(elementName+"="+list.item(i).getFirstChild().getNodeValue()); //取出元素的值
        }
        System.out.println("------------------------------------------");
    }
    
    public static void addElement(Document doc,Element root,String name,String age,String sex){
        Element student=doc.createElement("student");
        Element ename=doc.createElement("name");
        Element eage=doc.createElement("age");
        Element esex=doc.createElement("sex");
              
        ename.appendChild(doc.createTextNode(name));
        eage.appendChild(doc.createTextNode(age));
        esex.appendChild(doc.createTextNode(sex));
        
        student.appendChild(ename);
        student.appendChild(eage);
        student.appendChild(esex);
        
        root.appendChild(student);
    }
    
    public static Document createDocument() throws Exception{
        DocumentBuilderFactory dbf=DocumentBuilderFactory.newInstance();
        DocumentBuilder db=dbf.newDocumentBuilder();
        Document doc=db.newDocument();
        return doc;
    }
    
    public static void main(String[] args) throws Exception{
/*
output the xml
<class name="计算机1班">
    <student>
       <name>
       <age>
       <sex>
    </student>
    <student>
       <name>
       <age>
       <sex>
    </student>
</class>

 */    
        Document doc=createDocument();
        doc.createProcessingInstruction("encoding","gb2312");
        Element root=doc.createElement("class");
        root.setAttribute("name","计算机1班");
        doc.appendChild(root);
        
        addElement(doc,root,"黄蓉","30","女");
        addElement(doc,root,"郭靖","32","男");
        addElement(doc,root,"杨过","8","男");
        
        outputElement(doc,"name");
        outputElement(doc,"sex");
        
        writeXml(doc,"mydomxml.xml");
        System.out.println("output ok.");
                
    }
}

posted @ 2006-09-26 14:36 2195113 阅读(180) | 评论 (0)编辑 收藏

关于ThreadLocal的使用

1.线程中要使用的类.各线程只有其一个引用.

public class VarClass {
   
    private static ThreadLocal threadVar=new ThreadLocal(){
        protected synchronized Object initialValue(){
            System.out.println(Thread.currentThread().getName()+" initial value is 1");
            return new Integer(1);
        }};
   
    public int getValue(){
        return ((Integer)threadVar.get()).intValue();
    }
   
    public void setValue(){
        int a=getValue();
        a++;
        threadVar.set(new Integer(a));
    }
}


2.线程类

public class Worker extends Thread {
    private long interval=0;
    private boolean isRun=true;
    private VarClass v=null;
   
    public Worker(String name,VarClass v,long interval){
        setName(name);
        this.v=v;
        this.interval=interval;
    }

    public void run() {
        while(isRun){
            try{
                Thread.sleep(interval);
            }catch(InterruptedException e){
                e.printStackTrace();
            }
            v.setValue();
        }
        System.out.println(getName()+" is over at "+v.getValue());
    }
   
    public void stopThread(){
        isRun=false;
    }
}


3.测试类
public class TestThreadLocal {
   public static void main(String[] args){
       VarClass v=new VarClass();
      
       Worker w1=new Worker("Thread_A",v,100);
       Worker w2=new Worker("Thread_B",v,200);
       Worker w3=new Worker("Thread_C",v,300);
       Worker w4=new Worker("Thread_D",v,400);
       Worker w5=new Worker("Thread_E",v,500);
      
       w1.start();
       w2.start();
       w3.start();
       w4.start();
       w5.start();
                         
       System.out.println("All threads is over after 20 seconds");
      
       //延时20秒后,终止5个线程
       try{
           Thread.sleep(20000);
       }catch(InterruptedException e){
           e.printStackTrace();
       }
      
       System.out.println("All threads will be overed");
       w1.stopThread();
       w2.stopThread();
       w3.stopThread();
       w4.stopThread();
       w5.stopThread();
  }
}


4.测试结果:
All threads is over after 20 seconds
Thread_A initial value is 1
Thread_B initial value is 1
Thread_C initial value is 1
Thread_D initial value is 1
Thread_E initial value is 1
All threads will be overed
Thread_A is over at 200
Thread_B is over at 101
Thread_D is over at 51
Thread_C is over at 68
Thread_E is over at 42

5.结果说明:虽然各线程使用的是同一个对象的引用,但由于使用了ThreadLocal,实际上每个线程所操作的数据是不一样的.

posted @ 2006-09-25 16:18 2195113 阅读(205) | 评论 (0)编辑 收藏

Base64编码原理(随记)

1. Base64使用A--Z,a--z,0--9,+,/ 这64个字符.
2. 编码原理:将3个字节转换成4个字节( (3 X 8) = 24 = (4 X 6) )
            先读入3个字节,每读一个字节,左移8位,再右移四次,每次6位,这样就有4个字节了.
3. 解码原理:将4个字节转换成3个字节.
            先读入4个6位(用或运算),每次左移6位,再右移3次,每次8位.这样就还原了.

posted @ 2006-09-21 16:29 2195113 阅读(988) | 评论 (0)编辑 收藏

proxool连接池的配置

proxool连接池的配置(0.8.3)

1. 配置文件(xml形式,文件名任意)
--------------------------------
<?xml version="1.0"?>
<!-- the proxool configuration can be embedded within your own application's.
Anything outside the "proxool" tag is ignored. -->

<something-else-entirely>
  <proxool>
    <alias>mypool</alias>  <!-- add "proxool" before alias -- proxool.alias -->
    <driver-url>jdbc:oracle:thin:@localhost:1521:oradb</driver-url>
    <driver-class>oracle.jdbc.driver.OracleDriver</driver-class>
    <driver-properties>
      <property name="user"     value="username"/>
      <property name="password" value="password"/>
    </driver-properties>
    <connection-lifetime>60</connection-lifetime>
        <maximum-connection-count>50</maximum-connection-count>
    <minimum-connection-count>4</minimum-connection-count>
    <house-keeping-test-sql>select CURRENT_DATE</house-keeping-test-sql>
  </proxool>
</something-else-entirely>


2.web.xml配置
--------------
<servlet>
    <servlet-name>ServletConfigurator</servlet-name>
        <servlet-class>
        org.logicalcobwebs.proxool.configuration.ServletConfigurator
        </servlet-class>
    <init-param>
        <param-name>xmlFile</param-name>
        <param-value>WEB-INF/proxool.xml</param-value>
        </init-param>
    <load-on-startup>1</load-on-startup>
</servlet>

<!-- monitor proxool status -->
<servlet>
    <servlet-name>Admin</servlet-name>
    <servlet-class>org.logicalcobwebs.proxool.admin.servlet.AdminServlet</servlet-class>
</servlet>
<servlet-mapping>
    <servlet-name>Admin</servlet-name>
    <url-pattern>/admin</url-pattern>
</servlet-mapping>


3. 程序调用
Connection conn=null;
try {
    Class.forName("org.logicalcobwebs.proxool.ProxoolDriver");
    conn = DriverManager.getConnection("proxool.mypool"); //add "proxool" before "mypool" in proxool.xml
}catch(ClassNotFountException e){
    e.printStackTrace();
}catch(SQLException e) {
    e.printStackTrace();
}



posted @ 2006-08-03 14:03 2195113 阅读(622) | 评论 (0)编辑 收藏