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: qDS~|<Y5
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CountBean.java ^U9b)KA
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/* >H5_,A}f
* CountData.java /$d#9Uv
* tISb' ^T
* Created on 2007年1月1日, 下午4:44 eRm*+l|?
* 8I~*9MUp
* To change this template, choose Tools | Options and locate the template under 2)Q%lEm`SP
* the Source Creation and Management node. Right-click the template and choose Mw`S.M. B
* Open. You can then make changes to the template in the Source Editor. yu}T><Wst
*/ SveP:uJA[
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package com.tot.count; 0
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/** bg2r
* F?Fxm*Wa/
* @author =d$m@rc0r
*/ ; EsfHCi)
public class CountBean { *QT7\ht3
private String countType; ZEB,Q~
int countId; bo#?,80L}`
/** Creates a new instance of CountData */ ]P2Wa
public CountBean() {} =%S*h)}@
public void setCountType(String countTypes){ =)f.Yf|A*
this.countType=countTypes; a|ZJzuqo
} ]u\-_PP
public void setCountId(int countIds){ F6ZL{2$k@
this.countId=countIds; "`V:4uz
} NftR2
public String getCountType(){ U9XOs)^
return countType; C;YtMY:
} _4LDzVjNRe
public int getCountId(){ ?s]?2>p
return countId; gWl49'S>+
} w x,gth*p
} L4<=,}KS
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CountCache.java @Ll^ze&HI
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/* |H%,>r`9S
* CountCache.java p[%B#(]9,
* loD:4e1
* Created on 2007年1月1日, 下午5:01 in>?kbaG+
* 0BN=>]V~j7
* To change this template, choose Tools | Options and locate the template under ^=
'+#|:
* the Source Creation and Management node. Right-click the template and choose ={I(i6
* Open. You can then make changes to the template in the Source Editor. 17lc5#^L
*/ ej[Y
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package com.tot.count; 85{@&T
import java.util.*; gFxa UrZA
/** .c@,$z2M
* mSp;(oQ
* @author lmx'w
*/ 6z5?9I4[
public class CountCache { !I Byv%m&\
public static LinkedList list=new LinkedList(); | EFbT>
/** Creates a new instance of CountCache */ *KPNWY9!W
public CountCache() {} eSSv8[u
public static void add(CountBean cb){ {&h=
if(cb!=null){ Tl*FK?)MC^
list.add(cb); ETaLE[T%1
} }#E~XlX^
} Es+BV+x[.c
} ANd#m9(x
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CountControl.java k^\>=JTq=
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/* X-5&c$hv
* CountThread.java $c24l J#/
* -42jeJS
* Created on 2007年1月1日, 下午4:57 1{bsh?zd
* / Hexv#3
* To change this template, choose Tools | Options and locate the template under G `JXi/#`
* the Source Creation and Management node. Right-click the template and choose 1 =9 Kwd
* Open. You can then make changes to the template in the Source Editor. G
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*/ N,u~ZEI
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package com.tot.count; M2y"M ,k4
import tot.db.DBUtils; 6Er%td)f
import java.sql.*; ' Y.s}Duj
/** R6dD17
* GA@Zfcg
* @author u6BLhyS
*/ #zc{N"!
public class CountControl{ 0:3<33]x
private static long lastExecuteTime=0;//上次更新时间 `K\(I#z
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 oS_<;Fj
/** Creates a new instance of CountThread */ s~Od(,K
public CountControl() {} 0Xw3h^%
public synchronized void executeUpdate(){ }u8 D5Q<(
Connection conn=null; s1NRUV2E
PreparedStatement ps=null; ;COZHj9b
try{ qlfYX8edZ
conn = DBUtils.getConnection(); 9% AL f 9
conn.setAutoCommit(false); x'wT%/hp
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); PEX(*GS
for(int i=0;i<CountCache.list.size();i++){ nyR4E}@:O
CountBean cb=(CountBean)CountCache.list.getFirst(); YPqp#X*
CountCache.list.removeFirst(); edD"jq)J
ps.setInt(1, cb.getCountId()); xYCX}bksh
ps.executeUpdate();⑴ R2$;f?;:
//ps.addBatch();⑵ b
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} fd Rw:K8
//int [] counts = ps.executeBatch();⑶ /|2#s%|-=
conn.commit(); pn6!QpV5
}catch(Exception e){ C) "|sG
e.printStackTrace(); wIT}>8o
} finally{ -w:F8k ~
try{ =D2x@ank[
if(ps!=null) { 1Q ^YaHzuW
ps.clearParameters(); @dj2#
ps.close(); DIurFDQSS
ps=null; uZ(j"y
} }{Ncww!iN
}catch(SQLException e){} aGY F\7
DBUtils.closeConnection(conn); j7)Xm,wI8
} Z'~yUo=
} -Vi"hSsUP
public long getLast(){ 3+2&@:$t
return lastExecuteTime; 1>SCY_Cv
} duKR;5:
public void run(){ d
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long now = System.currentTimeMillis(); 0?",dTf3i
if ((now - lastExecuteTime) > executeSep) { )MKzAAt~
//System.out.print("lastExecuteTime:"+lastExecuteTime); 9j[%Y?
//System.out.print(" now:"+now+"\n"); jtk2>Ol
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); idf~"a
lastExecuteTime=now; a
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executeUpdate(); "s]c79t
} ~ YKBxt
else{ O&!tW^ih
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 0~\Dd0W/:`
} y#3mc#)k
} r2T-= XWB
} %jK-}0Tu
//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 UpgY}pf}
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类写好了,下面是在JSP中如下调用。 F(8>"(C
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<% szC~?]<YY
CountBean cb=new CountBean(); eyZ /%4'q
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 9tVA.:FOZ
CountCache.add(cb); PX3rHKK{
out.print(CountCache.list.size()+"<br>"); 38dXfl
CountControl c=new CountControl(); )POuH*j
c.run(); Eg?6$[U`8<
out.print(CountCache.list.size()+"<br>"); )~<8j
%>