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: 7I $~E
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CountBean.java -$ VP#%
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/* [
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* CountData.java 7^oO
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* |#b]e|aP
* Created on 2007年1月1日, 下午4:44 +nIjW;RU
* mi';96
* To change this template, choose Tools | Options and locate the template under LJ8 t@ui
* the Source Creation and Management node. Right-click the template and choose >fq]c
* Open. You can then make changes to the template in the Source Editor. sQ}E4Iq1#S
*/ ;_K3/:
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package com.tot.count; )K}-z+$)k
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/** ufF>I
* L*8U.{NY
* @author [yhK4A
*/ mEZHrr J
public class CountBean { Ueb&<tS
private String countType; c98^~vR]]
int countId; ^\f1zg9I
/** Creates a new instance of CountData */ hNRN`\5Z
public CountBean() {} 94}y,\S~
public void setCountType(String countTypes){ -u$U~?|`
this.countType=countTypes; {aVRvZH4
}
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public void setCountId(int countIds){ Ql1J?9W
this.countId=countIds; kf:Nub+h t
} eY V Jk7
public String getCountType(){ Ylhy Z&a,
return countType; zl3GWj|?\7
} RxYC]R^78
public int getCountId(){ =j"bLX6;
return countId; _2a)b(<tF
} *-';ycOvr
} KaIkO8Dq0
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CountCache.java |V&E q>G
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/* 8yC/:_ML
* CountCache.java 8+,I(+
* 47=YP0r?>T
* Created on 2007年1月1日, 下午5:01 Qx_]oz]NY
* edL sn>\*#
* To change this template, choose Tools | Options and locate the template under ,Dy9-o
* the Source Creation and Management node. Right-click the template and choose rU
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* Open. You can then make changes to the template in the Source Editor. i )!+`w*Y
*/ =x@v{cP
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package com.tot.count; 0JXXJ:d B
import java.util.*; [$D%]]/,
/** IcA]B?+
* 7NMy1'-q
* @author }3/|;0j$
*/ 6n:oEXM>
public class CountCache { %D49A-R
public static LinkedList list=new LinkedList(); Y_FQB K U
/** Creates a new instance of CountCache */ 5|A"YzY#
public CountCache() {} !DkIM}.
public static void add(CountBean cb){ }a"koL
if(cb!=null){ 4d8}g25C
list.add(cb); +&4@HHU{G
} ) E*-
} Kw =RqF
} FM"[:&>
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CountControl.java oi7Y?hTj
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/* 4jw q$G
* CountThread.java _/NPXDL
* )tx2lyY:
* Created on 2007年1月1日, 下午4:57 9hei8L:
* d-jZ 5nl(
* To change this template, choose Tools | Options and locate the template under "9#hk3*GqX
* the Source Creation and Management node. Right-click the template and choose J6mUU3F9f
* Open. You can then make changes to the template in the Source Editor. HBm(l@#.
*/ G2dPm}s ZG
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package com.tot.count; (7C$'T-ZK
import tot.db.DBUtils; i
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import java.sql.*; k{
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/** w:9M6+mM^
* lE8(BWzw
* @author tP89gN^PA|
*/ KP_7h/e
public class CountControl{ zHD8\*
private static long lastExecuteTime=0;//上次更新时间 wAo6:)
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 -XfGF<}r
/** Creates a new instance of CountThread */ F8xu&Vk0:
public CountControl() {} 0E7h+]bh|
public synchronized void executeUpdate(){ t9r
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Connection conn=null; r2\}_pIj
PreparedStatement ps=null; Flaqgi/j
try{ N>w+YFM
conn = DBUtils.getConnection(); xD9ZL
conn.setAutoCommit(false); 7[1VFc#tf
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ybv]wBpM:
for(int i=0;i<CountCache.list.size();i++){ ;!j/t3#a
CountBean cb=(CountBean)CountCache.list.getFirst(); ~xJ^YkyH
CountCache.list.removeFirst(); `o0ISJeKp
ps.setInt(1, cb.getCountId()); 3uL$+F
ps.executeUpdate();⑴ epI~w
//ps.addBatch();⑵ o QR?H
} t!59upbN}3
//int [] counts = ps.executeBatch();⑶ rAk;8)O$
conn.commit(); ~i0>[S3'
}catch(Exception e){ Y=@iD\u
e.printStackTrace(); *i"Mu00b
} finally{ p\}!uS4 (
try{ +I@2,T(eG
if(ps!=null) { 75iudki
ps.clearParameters(); 2RdpVNx\y
ps.close(); `)NTJc$):
ps=null; CdKs+x&tZ
} TA+#{q+a
}catch(SQLException e){} _ucixM#
DBUtils.closeConnection(conn); ^97[(89G9
} Ky*xAx:
} ,=2)1I]
public long getLast(){ dKmPKeJM
return lastExecuteTime; Lr Kx
} !Pu7%nV.
public void run(){ \==Mgy2J8
long now = System.currentTimeMillis(); r;O?`~2'4
if ((now - lastExecuteTime) > executeSep) { M"foP@
//System.out.print("lastExecuteTime:"+lastExecuteTime); Pr,C)uch
//System.out.print(" now:"+now+"\n"); _MTvNs
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); q)PSHr=Z
lastExecuteTime=now; 2<*Yq8
executeUpdate(); KP!7hJhw
} nyZ?m
else{ 'i;ofJ[.c
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ~Fo`Pr_
} W$`
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} r<;Y4<,BZ
} F#o{/u?T
//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 5a/3nsup5
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类写好了,下面是在JSP中如下调用。 =nCV.Wf
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<% wKJK!P
CountBean cb=new CountBean(); fN
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); PAiVUGp5[
CountCache.add(cb);
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out.print(CountCache.list.size()+"<br>"); R(2MI}T
CountControl c=new CountControl(); V3_qqz}`r
c.run(); oTA'=<W?D
out.print(CountCache.list.size()+"<br>"); lEpPi@2PK
%>