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: YM/3VD
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CountBean.java F p=Q$J|
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/* tVh4v#@+
* CountData.java dcTM02kEh
* Am`A[rV0
* Created on 2007年1月1日, 下午4:44 >]08".ajS
* r^tXr[}
* To change this template, choose Tools | Options and locate the template under =
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* the Source Creation and Management node. Right-click the template and choose VKJ~ZIO@A
* Open. You can then make changes to the template in the Source Editor. F^bQ-
*/ xgw)`>p,W
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package com.tot.count; 7a_n\]t465
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/** +6Fdi*:
* &)}:Y!qiu
* @author >xMhA`l
*/ t
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public class CountBean { >(4S `}K
private String countType; (GOrfr
int countId; "?(Fb_}i
/** Creates a new instance of CountData */ \kGtYkctZ
public CountBean() {} 7tO$'q*h
public void setCountType(String countTypes){ nVA'O
this.countType=countTypes; |}y}o:(
} dX}dO)%m{
public void setCountId(int countIds){ YhK/pt43C
this.countId=countIds; ){|Lh(
} %1+~(1P
public String getCountType(){ N}<U[nh'
return countType; v 5ddb)
} JkDZl?x5
public int getCountId(){ 'Mhdw}
return countId; W_n.V" hN
} {%~Ec4r
} f9=X7"dzP
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CountCache.java . pEeR
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/*
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* CountCache.java NGZ>:
* "/h"Xg>q
* Created on 2007年1月1日, 下午5:01 NJ!#0[@C
* Dk6\p~q
* To change this template, choose Tools | Options and locate the template under MQMy Z:
* the Source Creation and Management node. Right-click the template and choose >gLyz2
* Open. You can then make changes to the template in the Source Editor. n|2-bRK-
*/ K T72D
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package com.tot.count; 6Tmb@<I_
import java.util.*; ^`5Yxpz
/** Z`KXXlJ^i
* m:<3d]L
* @author d"a7{~l
*/ 7%}}m&A7h
public class CountCache { uy\+#:44d
public static LinkedList list=new LinkedList(); :2d9ZDyD
/** Creates a new instance of CountCache */ 5F?g6?j{
public CountCache() {} 9f[[%80
public static void add(CountBean cb){ hRcJ):Wyb
if(cb!=null){ A'R sy6
list.add(cb); #e|kA&+8M
} A0sW 9P6F
} q)i(wEdUZ
} y9 '3vZ
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CountControl.java /k Vc7LC
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/* xF31%b`z:
* CountThread.java 'J2P3t
* 3goJ(XI
* Created on 2007年1月1日, 下午4:57 nQVBHL>
* &y+*3,!n8
* To change this template, choose Tools | Options and locate the template under yKhzymS}T
* the Source Creation and Management node. Right-click the template and choose $X]v;B)J|
* Open. You can then make changes to the template in the Source Editor. z:7F5!Z
*/ ?bA]U:
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package com.tot.count; DYl{{L8@
import tot.db.DBUtils; `t2! M\)
import java.sql.*; CU&,Kq@
/** 9xp
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* |?W
* @author O:R{4Q*5
*/ $QnfpM%+=
public class CountControl{ 0P
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private static long lastExecuteTime=0;//上次更新时间 yln.E vJjD
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 E:OeU_\
/** Creates a new instance of CountThread */ AtYYu
public CountControl() {} Tr!X2#)A!
public synchronized void executeUpdate(){ N^at{I6C
Connection conn=null; KPqI(
PreparedStatement ps=null; =MLL-a1
try{ s``L?9
conn = DBUtils.getConnection(); oI/ThM`=q
conn.setAutoCommit(false); i*>yUav"
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); <3CrCEPC
for(int i=0;i<CountCache.list.size();i++){ w;_=$L'H&G
CountBean cb=(CountBean)CountCache.list.getFirst(); 7NEn+OI4
CountCache.list.removeFirst(); AV!
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ps.setInt(1, cb.getCountId()); Inoou'jX
ps.executeUpdate();⑴ +y(h/NcQ
//ps.addBatch();⑵ v[GHqZ
} g/gLG:C
//int [] counts = ps.executeBatch();⑶ Rgu^>
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conn.commit(); N `MQHQ1
}catch(Exception e){ [i _x
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e.printStackTrace(); gC- 0je
} finally{ xn[di-LF
try{ Xs_y!l
if(ps!=null) { &[pwLYf7
ps.clearParameters(); \)WjkhG<w#
ps.close(); 0<k!F3=
ps=null; X9wi:
} C3gz)!3
}catch(SQLException e){} XPKcF I=
DBUtils.closeConnection(conn); 58,mu#yq6
} ;zODp+4@Q
} "(GeW286k
public long getLast(){ w ?aLWySYT
return lastExecuteTime; (H^o8J
} %4J?xhd
public void run(){ UPF=X)!M
long now = System.currentTimeMillis(); O:)@J b2
if ((now - lastExecuteTime) > executeSep) { _aYQ(FO
//System.out.print("lastExecuteTime:"+lastExecuteTime); !vw0Y,F&
//System.out.print(" now:"+now+"\n"); {\I\4P
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); {lJpcS
lastExecuteTime=now; I^=M>_s4
executeUpdate(); "?-s
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} eH6cBX#P.
else{ i9tM]/SP
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); L zC~> Uj
} O*7
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} f0+
} DK;-2K
//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 g=8e.Y*Fr
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类写好了,下面是在JSP中如下调用。 5N0H^
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<% $-73}[UA 4
CountBean cb=new CountBean(); `PfC:L
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); .rHO7c,P~
CountCache.add(cb); S0cO00_ob
out.print(CountCache.list.size()+"<br>"); hrK^oa_[W
CountControl c=new CountControl(); IT|CfQ [D
c.run(); pP&~S<[
out.print(CountCache.list.size()+"<br>"); Lq.k?!D3uh
%>