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: Qf:e;1F!
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CountBean.java *l7 `C)
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/* X@~/.H5
* CountData.java {z o GwB
* 6#=Iv X4
* Created on 2007年1月1日, 下午4:44 "im5Fnu
* |~9jO/&r
* To change this template, choose Tools | Options and locate the template under eaRa+ <#u
* the Source Creation and Management node. Right-click the template and choose HNZ$CaJh
* Open. You can then make changes to the template in the Source Editor. iM .yen_vp
*/ z_c-1iXCW
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package com.tot.count; ekx(i
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/** X}#vt?mu
* G4
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* @author U]Q5};FK
*/ tB;PGk_6
public class CountBean { ;MfqI/B{
private String countType; |$
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int countId; uQdeKp4(
/** Creates a new instance of CountData */ f1NHW|_j
public CountBean() {} e1[ReZW
public void setCountType(String countTypes){ -Mo4`bN
this.countType=countTypes; c&;" Y{
} dv.
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public void setCountId(int countIds){ l0&Fm:))k
this.countId=countIds; {aE[h[=r
} /KH85/s
public String getCountType(){ b^R:q7ea
return countType; q/?*|4I
} Y%}&eN$r
public int getCountId(){ t[|rp&xG
return countId; ;adZ*'6u
} <EnmH/C.
} LJrH_h8C
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CountCache.java .{gDw
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/* F2YBkwI
* CountCache.java uGAQt9$>_
* @<K<"`~H
* Created on 2007年1月1日, 下午5:01
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* aG1Fj[,
* To change this template, choose Tools | Options and locate the template under -~z@W3\
* the Source Creation and Management node. Right-click the template and choose T4x%3-4;
* Open. You can then make changes to the template in the Source Editor. x& _Y( bHA
*/ } W]A`-Jv
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package com.tot.count; QFTiE1mGH
import java.util.*; Pll%O@K
/** U<Oc&S{]*
* Vg62HZ |
* @author /CALXwL
*/ &pK0>2
public class CountCache { &zYQH@
public static LinkedList list=new LinkedList(); +1#;s!e
/** Creates a new instance of CountCache */ k3&68+
public CountCache() {} A8ViJ
public static void add(CountBean cb){ +At[[
if(cb!=null){ )
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list.add(cb); /yU#UZ4;
} ?z&n I#
} shB3[W{}!)
} jl59;.P
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CountControl.java (6c/)MH
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/* N+~
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* CountThread.java [(
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* p#c41_?'e
* Created on 2007年1月1日, 下午4:57 XK~HfA?
* USART}Us4
* To change this template, choose Tools | Options and locate the template under 548L^"D
* the Source Creation and Management node. Right-click the template and choose /%&5Iq\:vA
* Open. You can then make changes to the template in the Source Editor. G{?`4=K
*/ koB'Zp/FaY
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package com.tot.count; RA a1^Qb
import tot.db.DBUtils; -75mgOj.#
import java.sql.*; <Hv/1:k}
/** `C_qqf
* h[!@8
* @author 'xd8rN%T
*/ i&(1<S>P
public class CountControl{ L0VZ>!*o
private static long lastExecuteTime=0;//上次更新时间 jNbVp{%/S}
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 jhRr!
/** Creates a new instance of CountThread */ _G)A$6weU
public CountControl() {} "T[BSj?E
public synchronized void executeUpdate(){ b1^wK"#
Connection conn=null; NJJ=ch
PreparedStatement ps=null; %,$xmoj9O]
try{ m|JA}&A
conn = DBUtils.getConnection(); 3'p1m`8
conn.setAutoCommit(false); 3LyNi$`f
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); wMgF*
for(int i=0;i<CountCache.list.size();i++){ RKrNmD*rk*
CountBean cb=(CountBean)CountCache.list.getFirst(); zWPX
CountCache.list.removeFirst(); ~%lUzabMa
ps.setInt(1, cb.getCountId()); {$t*XTY6R
ps.executeUpdate();⑴ %1
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//ps.addBatch();⑵ _{): w~zi
} "+2Cs
//int [] counts = ps.executeBatch();⑶ P,zQl;
conn.commit(); /7#MJH5b6
}catch(Exception e){ &g}P)xr
e.printStackTrace(); d@^%fVhG
} finally{ |L*=\%t8
try{ X}G$ON
if(ps!=null) { >/RFff]Fh0
ps.clearParameters(); ]
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ps.close(); nGX3_-U4
ps=null; {nM1$
} |[r7B*fw
}catch(SQLException e){} Xm< _!=
DBUtils.closeConnection(conn); FaJK
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} yk!K5
} }.s%J\ckx
public long getLast(){ Q(A$ >A
return lastExecuteTime; @gqZiFM)
} Rkg)yme!N
public void run(){ K%`]HW@I{
long now = System.currentTimeMillis(); C ]B P}MY<
if ((now - lastExecuteTime) > executeSep) { qh W]Wd"g
//System.out.print("lastExecuteTime:"+lastExecuteTime); DXj>u9*%
//System.out.print(" now:"+now+"\n"); b
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); {o^tSEN!-
lastExecuteTime=now; bD/ZKvg
executeUpdate(); 7V@r^/`8N
} &tbAXU5$
else{ #oiU|>3Y
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); W=g'Xu!|!2
} |d~'X%b%
} vaQsG6q[
} rF}Q(<Y86
//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 #c'B2Jn
}; 7I
类写好了,下面是在JSP中如下调用。 mc`Z;D/mt
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<% |<3x`l-`
CountBean cb=new CountBean(); sWse
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 4dN <B U
CountCache.add(cb); FS)#
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out.print(CountCache.list.size()+"<br>"); :!cK?H$+
CountControl c=new CountControl(); fp(zd;BSQ
c.run(); $;(@0UDE
out.print(CountCache.list.size()+"<br>"); *MlEfmB(
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