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: #vPk
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CountBean.java
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/* Maiy d
* CountData.java a]I~.$G
* M%Q_;\?]
* Created on 2007年1月1日, 下午4:44 AJP-7PPD
* [-#q'S
* To change this template, choose Tools | Options and locate the template under _IvqZ/6Y(
* the Source Creation and Management node. Right-click the template and choose cZw_^@!
* Open. You can then make changes to the template in the Source Editor. u$ ^r(.EV
*/ :QMpp}G
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package com.tot.count; %V-Hy ;V
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/** GbC JGqOR
* +#@2,
* @author U(<~("ocN
*/ ~jC$C2A0
public class CountBean { tA
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private String countType; :,'.b|Tl.b
int countId; cs]3Rp^g
/** Creates a new instance of CountData */ R~#&xfMd.
public CountBean() {} ]TsmW ob
public void setCountType(String countTypes){ 2]tW&y_i
this.countType=countTypes; AxCFZf 5
} [Lf8*U"
public void setCountId(int countIds){ 4&B|rf
this.countId=countIds; y*I,i*iv
} : p7PiqQ
public String getCountType(){ z,SNJIsx
return countType; F Zk[w>{
} 3X1
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public int getCountId(){ \YH*x`
return countId; }y%mG&KSz
} XBTjb
} z+nq<%"'
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CountCache.java ZVCa0Km
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/* //^{u[lr
* CountCache.java Lo +H&-
* G-DOI
* Created on 2007年1月1日, 下午5:01 }wGy#!CSza
* ESkhCDU
* To change this template, choose Tools | Options and locate the template under U
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* the Source Creation and Management node. Right-click the template and choose #|
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* Open. You can then make changes to the template in the Source Editor. JvtbGPz
*/ !LpFK0rw
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package com.tot.count; .gw6W0\F
import java.util.*; 8oP"?ew#
/** x\5\KGw16
* %lGg}9k'
* @author TnPx.mwK\
*/ 5^36nEoA(
public class CountCache { F\+!\b*lP
public static LinkedList list=new LinkedList(); ov'C0e+o
/** Creates a new instance of CountCache */ a &hj|
public CountCache() {} stOD5yi
public static void add(CountBean cb){ :j;_Xw
if(cb!=null){ )oMMDHw\
list.add(cb); M` |E)Y
} G5$YXNV
} 5g
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} PtOYlZTe?
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CountControl.java -p20UP 1I
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/* )`<7qT_BM
* CountThread.java L!:;H,
* ,Z[pLF
* Created on 2007年1月1日, 下午4:57 W_|7hwr
* k FE<M6a9@
* To change this template, choose Tools | Options and locate the template under Fr,b5 M<L7
* the Source Creation and Management node. Right-click the template and choose Ng\]
* Open. You can then make changes to the template in the Source Editor. S6c>D&Q
*/ Xxs0N_va&
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package com.tot.count; }9Awv#+
import tot.db.DBUtils; j$khGR!
import java.sql.*; 6b h.5|
/** e|.a%,Dcy
* * l-F
* @author l gTw>r
*/ n`|CDKb
public class CountControl{ ?4lEHef
private static long lastExecuteTime=0;//上次更新时间 bU_P@GKB
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Hr=?_Un"
/** Creates a new instance of CountThread */ :n$?wp
public CountControl() {} A55F *d
public synchronized void executeUpdate(){ A{\!nq_~N
Connection conn=null; ||rZ+<
PreparedStatement ps=null; r-c1_
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try{ [J43]
conn = DBUtils.getConnection(); Zex`n:Wl?j
conn.setAutoCommit(false); 4tFnZ2x
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); >W=^>8u
for(int i=0;i<CountCache.list.size();i++){ EZ)GW%Bm2
CountBean cb=(CountBean)CountCache.list.getFirst(); Ly`FU)
CountCache.list.removeFirst(); qUG)+~g`
ps.setInt(1, cb.getCountId()); QQX7p!~E
ps.executeUpdate();⑴ {3\{aZ8)
//ps.addBatch();⑵ XM?C7/^k
} 3qrjb]E%}
//int [] counts = ps.executeBatch();⑶ $WZHkV
conn.commit(); Z`{GjV3%wH
}catch(Exception e){ Xa&0j&AH
e.printStackTrace(); 604^~6
} finally{ C)+%9Edg
try{ Cg%}=
if(ps!=null) { w:@W/e*9N
ps.clearParameters(); jg=}l1M"
ps.close(); UJrN+RtL
ps=null; LKu
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} #:}mi;{
}catch(SQLException e){} (Z at|R.F
DBUtils.closeConnection(conn); ;%$wA5"2M
} 9I*`~il>{
} `'/1Ij+
public long getLast(){ P<IZ%eS3B
return lastExecuteTime; 5t[7taLX\
} ^
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public void run(){ 0tP{K
long now = System.currentTimeMillis(); H@ .1cO
if ((now - lastExecuteTime) > executeSep) { .jbT+hhM
//System.out.print("lastExecuteTime:"+lastExecuteTime); qJ<Ghd`8v
//System.out.print(" now:"+now+"\n"); ZTK)N
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ^h"F\vIpV
lastExecuteTime=now; ]Kp -2KW
executeUpdate(); MHAWnH8
} #i[V{J8.p
else{ 7>yb8/J
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); cW\Y1=Gv|
} 1Et{lrgh
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} Xa/]}
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} \$D41_Wt|
//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 ;F\sMf{
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类写好了,下面是在JSP中如下调用。 LkUi^1((e
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<% km9@*@)
CountBean cb=new CountBean(); 0*8uo
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); (,2U?p
CountCache.add(cb); A>QAR)YP
out.print(CountCache.list.size()+"<br>"); -bQi4
CountControl c=new CountControl(); 6ragRS/'x
c.run(); G0pqiU6
out.print(CountCache.list.size()+"<br>"); -owap-Va
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