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: %5ovW<E:
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CountBean.java EpCF/i?9:
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/* ey@{Ng#
* CountData.java =oT4!OUf
* jY k5]2#A
* Created on 2007年1月1日, 下午4:44 Eyq4w
* {WvYb,
* To change this template, choose Tools | Options and locate the template under '>k1h.i
* the Source Creation and Management node. Right-click the template and choose mfx-Ja_a
* Open. You can then make changes to the template in the Source Editor. dlRTxb^Y>u
*/ tNG[|Bi#
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package com.tot.count; Y3JIDT^
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/** G Ml JM
* )W/_2Q.
* @author &Lbh?C
*/ hplx s#
public class CountBean { OK(xG3T
private String countType; J-z<&9
int countId; j;J`PH
/** Creates a new instance of CountData */ INEE
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public CountBean() {} NXMZTZpB7
public void setCountType(String countTypes){ nyL$z-I)
this.countType=countTypes; &N*l ?7(
} AAF']z<4_"
public void setCountId(int countIds){ *G8Z[ht%r
this.countId=countIds; +y^'\KN
} ~(`&hYE
public String getCountType(){ +E']&v$
return countType; Vy6~O|68=
} B9wQ;[gQB
public int getCountId(){ b$sT`+4q
return countId; Md&K#)9,(
} AquO#A[,#
} u{cb[M
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CountCache.java aF[#(PF
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/* b!qlucAeE
* CountCache.java ?CldcxM#
* iD<}r?Z
* Created on 2007年1月1日, 下午5:01 IEe;ygL#
* ,n`S
,
* To change this template, choose Tools | Options and locate the template under qIxe)+.
* the Source Creation and Management node. Right-click the template and choose +LlAGg]Z
* Open. You can then make changes to the template in the Source Editor. Js(MzL
*/ <Ira~N
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package com.tot.count; l=L(pS3 ~
import java.util.*; F_&H*kL L3
/** .hjN*4RY
* }}l jVUpC%
* @author =
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*/ w,j;XPp
public class CountCache { \wR\i^
public static LinkedList list=new LinkedList(); ]MC5 uKn
/** Creates a new instance of CountCache */ 8@
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public CountCache() {} X<H{
public static void add(CountBean cb){ -wVuM.n(Z
if(cb!=null){ ]G^9PZ-
list.add(cb); [
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} q.j$]?PQ
} >>cL"m
} lYey7tl{
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CountControl.java fu?u~QZ8
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/* >Bu_NoM
* CountThread.java .*Bd'\:F/q
* ,t!I%r
* Created on 2007年1月1日, 下午4:57 Oc-ia)v1G
* KL*+gq0k
* To change this template, choose Tools | Options and locate the template under cM\BEhh
* the Source Creation and Management node. Right-click the template and choose 7`e<H 8g
* Open. You can then make changes to the template in the Source Editor. Wz#ZkNO
*/ b;nqhO[f}
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package com.tot.count; yZ]?-7
import tot.db.DBUtils; Asy2jw\V
import java.sql.*; xe9\5Gb}
/** $ab{GxmX'4
* #V$sb1u
* @author BU7QK_zT:
*/ ,1]VY/
public class CountControl{ =dmxE*C
private static long lastExecuteTime=0;//上次更新时间 )<Mo.
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 J(A+mYr{:
/** Creates a new instance of CountThread */ lTVz'ys
public CountControl() {} 5DO}&%.xt
public synchronized void executeUpdate(){ {bG. X?b
Connection conn=null; 4q(,uk&R[
PreparedStatement ps=null; EfkBo5@ Qi
try{ rv<qze;?|
conn = DBUtils.getConnection(); HGi%b5:<=M
conn.setAutoCommit(false); Z_7TD)
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); WI.+9$1:P
for(int i=0;i<CountCache.list.size();i++){ ;bL?uL
CountBean cb=(CountBean)CountCache.list.getFirst(); AP8J28I
CountCache.list.removeFirst(); >GzH_]
ps.setInt(1, cb.getCountId()); 8#9OSupp
ps.executeUpdate();⑴ |tz{Es<`B
//ps.addBatch();⑵ ]\]mwvLT
} t{ `-G*^
//int [] counts = ps.executeBatch();⑶
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conn.commit(); Q5u3~Q'e
}catch(Exception e){ }WF6w+
e.printStackTrace(); Y&y<WN}Q
} finally{ k^K%."INn
try{ K6@ %@v
if(ps!=null) { 1v<uA9A%[
ps.clearParameters(); AgB$
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ps.close(); KXUJ*l-5
ps=null; ;=@?( n
} f9hH{(A
}catch(SQLException e){} ^K
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DBUtils.closeConnection(conn); zm4e+v-
} ,4}s 1J#
} /b6j<]H
public long getLast(){ 7t78=wpLc
return lastExecuteTime; . TNJuuO
} >feeVk
public void run(){ c:s[vghH^#
long now = System.currentTimeMillis(); RER93:(
if ((now - lastExecuteTime) > executeSep) { Ie8SPNY-H
//System.out.print("lastExecuteTime:"+lastExecuteTime); f9'dZ}B
//System.out.print(" now:"+now+"\n"); ?3i<^@?
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); h*sL' fJ]
lastExecuteTime=now; h(^[WSa
executeUpdate(); U;gy4rj
} 6c}nP[6|
else{ WckWX]};S
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); [.;8GMW
} 'o7V6KG
} -NDB.~E^DJ
} $us7fuKE
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 aDE}'d1qo
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类写好了,下面是在JSP中如下调用。 '2{60t_A
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<% g=Nde2d?
CountBean cb=new CountBean(); q-e3;$
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); e C&!yY2g
CountCache.add(cb); SWNT}{x]
out.print(CountCache.list.size()+"<br>"); \x"BgLSE
CountControl c=new CountControl(); 1NK,:m
c.run(); $@[Mo
out.print(CountCache.list.size()+"<br>"); +.X3&|@k
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