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深入探究:cookie技术在J2ME平台的应用

  第二:保存cookie

  已经获得了cookie之后,就需要把cookie存储下来,存储分为两个部分,首先需要解析cookie,我们定义一个JavaBean来代表cookie.

    packagecom.j2medev.lomol.model;
    importcom.j2medev.lomol.util.StringUtil;
    importjava.io.DataInputStream;
    importjava.io.DataOutputStream;
    importjava.io.IOException;
    importjava.util.Date;
    
/**  *acookiestoredonthemobiledevice,
    cookieisusedtomaintainthestatesbetweenclientandserver
    *@authormingjava
    *@version0.105/06/2006
    
*/
    publicclassCookie{
    privateStringpath
=""
    privateStringname
=""
    privateStringvalue
=""
    privatelongexpire
=SESSION_COOKIE;
    publicstaticlongSESSION_COOKIE
=0
    
//sessioncookie,onlyvalidthissession
    publicCookie(){  }
    publicStringgetPath(){  returnpath;  }
    publicvoidsetPath(Stringpath){  
this.path=path;  }
    publicStringgetName(){  returnname;  }
    publicvoidsetName(Stringname){  
this.name=name;  }
    publicStringgetValue(){  returnvalue;  }
    publicvoidsetValue(Stringvalue){  
this.value=value;  }
    publicvoidserialize(DataOutputStreamdos)
    throwsIOException{
    dos.writeUTF(name);
    dos.writeUTF(value);
    dos.writeUTF(path);
    dos.writeLong(expire);
    }
    publicstaticCookiedeserialize(DataInputStreamdis)throwsIOException{
    Cookiecookie
=newCookie();
    cookie.name
=dis.readUTF();
    cookie.value
=dis.readUTF();
    cookie.path
=dis.readUTF();
    cookie.expire
=dis.readLong();
    returncookie;
    }
    publiclonggetExpire(){
    returnexpire;
    }
    publicvoidsetExpire(longexpire){  
this.expire=expire;
    }
    
//fordebug
    publicStringtoString(){
    returnname
+"="+value+";expires="+newDate(expire)。
    toString()
+";path="+path;
    }
    publicbooleanisExpired(longnow){
    returnexpire
-now<0
    }
    publicbooleanisExpired(){
    returnexpire
-(newDate()。getTime())<0
    }
    publicstaticCookieparseCookie(Strings,Stringuri){
    Cookiecookie
=newCookie();
    StringUtilsu
=newStringUtil(s,"");
    
while(su.hasMoreTokens()){
    Stringstr
=su.nextToken()。trim();
    inti
=str.indexOf("=");
    
if(i==-1){
    
//securedonothing  continue;
    }else{
    Stringname
=str.substring(0,i);
    Stringvalue
=str.substring(i+1,str.length());
    
if"path".equals(name)){
    cookie.setPath(value);
    }elseif(
"expires".equals(name)){
    cookie.setExpire(StringUtil.getData(value));
    }elseif(
"domain".equals(name)){
    
//donothing  }else{
    cookie.setName(name);
    cookie.setValue(value);
    }  }
    
if(cookie.getPath()。equals(""))
    cookie.setPath(uri);  }  returncookie;  }
    publicbooleanequals(Objectobj){
    
if(objinstanceofCookie){  Cookieo=(Cookie)obj;
    
if(o.getName()。equals(name)&&o.getPath()。equals(path))
    returntrue;  }  returnfalse;  }
    publicinthashCode(){  intresult
=17
    resultresult
=result*37+path.hashCode();
    resultresult
=result*37+name.hashCode();
    returnresult;  }  }

  提供了一个parseCookie方法来解析cookie,具体的原理就不再介绍了。然后需要把这个Cookie对象存储到RMS中。cookie并不大,所以不会占用太多的空间,在RMS中存储非常合适。注意对于会话期间的cookie没有必要存储在rms中,因为会话结束后就失效了,不如在内存中声明一个Map来存储会话类型的cookie。

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