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: mB`HPT
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CountBean.java f7&ni#^Ztj
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/* h% -=8l,
* CountData.java JI@iT6.%IX
* h4n~V:nNm
* Created on 2007年1月1日, 下午4:44 AROHe
* ToHx!,tDS
* To change this template, choose Tools | Options and locate the template under MV5$e
* the Source Creation and Management node. Right-click the template and choose 5RT#H0/+
* Open. You can then make changes to the template in the Source Editor. D1RQkAZS
*/ |j+JLB
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package com.tot.count; ui?@:=
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/** )u(,.O[cw
* r*{.|>me
* @author 7{r7
*/ ~BI`{/O=
public class CountBean { 94!}
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private String countType; _N5pxe`
int countId; 27Gff(
/** Creates a new instance of CountData */ |;J`~H"K
public CountBean() {} 1feVFRx'
public void setCountType(String countTypes){ Sstz_t
this.countType=countTypes; BsA4/Bf
} Bl>m`/\1i
public void setCountId(int countIds){ ;1~ n|IY
this.countId=countIds; nKE^km
} "/R?XCBZsb
public String getCountType(){ %qV:h#
return countType; Ea4zC|;
} ]+G
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public int getCountId(){ 1#Vd)vSP
return countId; Yv1yRoDv
} 2z;nPup,
} pauO_'j_1p
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CountCache.java |K.I%B
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/* IfH/~EtX
* CountCache.java W2<'b05
* 'z91aNG]
* Created on 2007年1月1日, 下午5:01 oyiG04H&
* n{W(8K6d@[
* To change this template, choose Tools | Options and locate the template under ,L%]}8EL"
* the Source Creation and Management node. Right-click the template and choose M[985bl
* Open. You can then make changes to the template in the Source Editor. ~JRq :
*/ ;Qt%>Uo8
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package com.tot.count; 0s8fF"$
import java.util.*; :H>I`)bw
/** I*3>>VN
* [#!Y7Ede
* @author /sYr?b!/<6
*/ 8}BM`@MG
public class CountCache { 1#L%Q(G
public static LinkedList list=new LinkedList(); P:Q&lnC
/** Creates a new instance of CountCache */ dOaOWMrfdf
public CountCache() {} [m! P(o
public static void add(CountBean cb){ e>_a
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if(cb!=null){ sC"w{_D@*4
list.add(cb); 6# bTlmcg
} otaRA
} zZd.U\"2
} _k}Qe;
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CountControl.java 0[H/>%3O
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/* r7R39#
* CountThread.java }x|q*E\
* 9y[U\[H
* Created on 2007年1月1日, 下午4:57 ;Mmu}
* LT)I
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* To change this template, choose Tools | Options and locate the template under VOYQ<tg
* the Source Creation and Management node. Right-click the template and choose ydVDjE
Y
* Open. You can then make changes to the template in the Source Editor. Kf?:dF
*/ ;P<h9(
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package com.tot.count; j 0LZ )V
import tot.db.DBUtils; |)d%3s\
import java.sql.*; pcIS}+L
/** }x#e.}hf&
* JS03BItt
* @author XlX t,
*/ Pc?"H!Hkn
public class CountControl{ t!xdKX& }
private static long lastExecuteTime=0;//上次更新时间 W$7H "tg
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 oumbJ7X=L
/** Creates a new instance of CountThread */ du0o4~-
public CountControl() {} -~RGjx
public synchronized void executeUpdate(){ R:l &2
Connection conn=null; *oLDy1<
PreparedStatement ps=null; ]>Dbta.27
try{ ,yp#!gE~
conn = DBUtils.getConnection(); @8w[Z o~
conn.setAutoCommit(false); EhKG"Lb+
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); #Mk3cp^Yl
for(int i=0;i<CountCache.list.size();i++){ E>/~:
CountBean cb=(CountBean)CountCache.list.getFirst(); 5MYdLAjV
CountCache.list.removeFirst(); 'cu14m_
ps.setInt(1, cb.getCountId()); oP
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ps.executeUpdate();⑴ ?x 0gI
//ps.addBatch();⑵ $v_&jE
} n2_;:=
//int [] counts = ps.executeBatch();⑶ #%%!r$UL
conn.commit(); ePq (.o
}catch(Exception e){ t>a D;|Y
e.printStackTrace(); HNc/p4z
} finally{ LB({,0mcX
try{ .*n*eeD,
if(ps!=null) { 2rC&
ps.clearParameters(); E 6MeM'sx
ps.close(); :,yC\,H^
ps=null; >\~Er@
} sZ7,7E|_
}catch(SQLException e){} XgXXBKf$
DBUtils.closeConnection(conn); Z0v?3v}9^
} ]1zud
} #l`\'0`.
public long getLast(){ 30SQ&j[N]
return lastExecuteTime; ~K5A$s2
} QrFKjmD<
public void run(){ Y^DGnx("m
long now = System.currentTimeMillis(); 3.P7GbN
if ((now - lastExecuteTime) > executeSep) { Xf"<
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//System.out.print("lastExecuteTime:"+lastExecuteTime); O8>&J-+2
//System.out.print(" now:"+now+"\n"); "1XTgCu\
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); )/[L)-~y~
lastExecuteTime=now; XM"Qs.E
executeUpdate(); G=gU|& (
} }/\`'LQ
else{ \ntUxPox.
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); [n&ES\o#(
} 2wPc
yD
} \M|:EG%
} G; exH$y
//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 *"Iz)Xzc`
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类写好了,下面是在JSP中如下调用。 hbr3.<o1lY
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<% LXJ;8uW2y
CountBean cb=new CountBean(); 9@IL5 47V
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); NX8hFwR
CountCache.add(cb); WI*CuJU<zJ
out.print(CountCache.list.size()+"<br>"); 8lDb<i
CountControl c=new CountControl(); V?0IMc
c.run(); bYpeI(zK
out.print(CountCache.list.size()+"<br>"); ^~vM*.j~j
%>