有时要为每一篇文章统计其点击次数,如果每一次浏览都要更新一次库的话,那性能在访问量很大的情况下,服务器的压力就会很大了,比较好一点的方法就是先将要更新的数据缓存起来,然后每隔一段时间再利用数据库的批量处理,批量更新库。源码如下: yct^AN|%
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CountBean.java Q.]RYv}\
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/* L?p,Sy<RI
* CountData.java d!]fou
* 4?F7% ^vr
* Created on 2007年1月1日, 下午4:44 y|E{]
* fxL0"Ry
* To change this template, choose Tools | Options and locate the template under \IG"Te
* the Source Creation and Management node. Right-click the template and choose 4'ymPPY
* Open. You can then make changes to the template in the Source Editor. Xv1mjHZCC
*/ qOd*9AS'|M
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package com.tot.count; ,6FmU$
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/** 0(~,U!g[=
* *1fZcw'C.
* @author Ib665H7w
*/ 3gzcpFNqX
public class CountBean { tZn=[X~Vw@
private String countType; yvz2eAXa
int countId; FtL{f=
/** Creates a new instance of CountData */ }I;5yk,o
public CountBean() {} qC?\i['`
public void setCountType(String countTypes){ V=|X=:fuih
this.countType=countTypes; $Q!J.}P@
} p4-bD_
public void setCountId(int countIds){ 4,pS C
this.countId=countIds; =2yg:D
} _N-JRM m<
public String getCountType(){ ~Q)137u]P
return countType; 8!uqR!M<C
} 'WW['
public int getCountId(){ .^J7^Ky,
return countId; d5ivtK?
} j*aYh^
} 7JI&tlR4\c
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CountCache.java l;gj],*
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/* "Lp"o
* CountCache.java .`ppp!:a4
* ,`lVB#|
* Created on 2007年1月1日, 下午5:01 ^%qhE8
* .g6DKjy>
* To change this template, choose Tools | Options and locate the template under M~1 n#
* the Source Creation and Management node. Right-click the template and choose x>yeF,q1
* Open. You can then make changes to the template in the Source Editor. 8 O5@FU
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*/ 'F665
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package com.tot.count; mVBF2F<4
import java.util.*; 0$9I.%4jAJ
/** 5c~OG6COx
* FOU^Wcop%
* @author mjd9]HgN
*/ !MiH^wP
public class CountCache { V\V:uo(C
public static LinkedList list=new LinkedList(); ]EzX$T
/** Creates a new instance of CountCache */ ?/,sKF74i
public CountCache() {} )@]Y1r4U
public static void add(CountBean cb){ <2Qh5umQ
if(cb!=null){ +I+7@Xi Z
list.add(cb); +'NiuN
} ;i2N`t2
} NI^[7.2
} p<@0b
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CountControl.java !PfI e94{`
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/* lilKYrUmG
* CountThread.java fJ?$Z|
* ]eJjffx
* Created on 2007年1月1日, 下午4:57 GoGo@5n(Z
* i*JbFukG
* To change this template, choose Tools | Options and locate the template under Q7]VB p4
* the Source Creation and Management node. Right-click the template and choose }Dig'vpMx
* Open. You can then make changes to the template in the Source Editor. btC.EmX
*/ 1z\>>N$7B
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package com.tot.count; ;rj=hc
import tot.db.DBUtils; 90pk
import java.sql.*; hupYiI~
/** GMZj@q
* cN> z`xl
* @author A@wRP8<GKj
*/ hal3J
public class CountControl{ Eu AJ.n
private static long lastExecuteTime=0;//上次更新时间 'M*+HY\.0
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 (\si/&
/** Creates a new instance of CountThread */ fU+A~oL%I
public CountControl() {} {GS7J
public synchronized void executeUpdate(){ `NC{+A
Connection conn=null; }xl
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PreparedStatement ps=null; nJTV@mXVq
try{ ?^F#}>C
conn = DBUtils.getConnection(); c0Tda
conn.setAutoCommit(false); *n)3y.s
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); G}tq'#]E{z
for(int i=0;i<CountCache.list.size();i++){ ] Qp0|45=
CountBean cb=(CountBean)CountCache.list.getFirst(); G;+hc%3y
CountCache.list.removeFirst(); -L/5Nbup
ps.setInt(1, cb.getCountId()); MK]S205{
ps.executeUpdate();⑴ }{^i*T5rl
//ps.addBatch();⑵ {.We%{4V
} 1R/=as,R
//int [] counts = ps.executeBatch();⑶ -4JdKO
conn.commit(); =W9;rQm
}catch(Exception e){ k!]Tg"]JAh
e.printStackTrace(); "jVMk
} finally{ T
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try{ 13]sZ([B%|
if(ps!=null) { vXnTPjbE
ps.clearParameters(); K%<Z"2!+
ps.close(); <!\J([NM8
ps=null; ?Rl?Pp=>
} I3xx}^V
}catch(SQLException e){} BPnZ"w_
DBUtils.closeConnection(conn); ,=tVa])
} `@{qnCNQ
} A$RN7#
public long getLast(){ 9-+6Ed^2
return lastExecuteTime; x C'>W"pY
} ;bd\XHwMUP
public void run(){ ]?L?q2>&
long now = System.currentTimeMillis(); _4z>I/R>Z
if ((now - lastExecuteTime) > executeSep) { V%pdXM5
//System.out.print("lastExecuteTime:"+lastExecuteTime); nTSGcMI
//System.out.print(" now:"+now+"\n"); |WeLmy%9
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); XcA4EBRj
lastExecuteTime=now; S
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executeUpdate(); uU`zbh}]L.
} Mi\f?
else{ S8" h9|
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); EX8:B.z`57
} ushQWP)
} t=~5I>
} nTjQ4y
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 FuaGr0]
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类写好了,下面是在JSP中如下调用。 =o=)EU{~
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<% @4_CR
CountBean cb=new CountBean(); &l%#OI}OE
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 4EuZe:'X
CountCache.add(cb); tkWWR%c"
out.print(CountCache.list.size()+"<br>"); $g#j,
CountControl c=new CountControl(); }rVnuRq
c.run(); t09,X
out.print(CountCache.list.size()+"<br>"); oZ%t! Fl1
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