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: g(;ejKSR
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CountBean.java ]R]X#jm
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/* q+G1#5
* CountData.java ||,;07
* -)<Nd:A
* Created on 2007年1月1日, 下午4:44 ?,),%JQ
* G6Fg<g9:
* To change this template, choose Tools | Options and locate the template under Ri-wbYFaP
* the Source Creation and Management node. Right-click the template and choose sQH.}W$C
* Open. You can then make changes to the template in the Source Editor. @o^sp|k !
*/ #QDV_ziE5
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package com.tot.count; pcl_$2_
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/** 6<~y!\4;F
* {DO9{96w4
* @author Zd%\x[f9ck
*/ -jw=Iyv
public class CountBean { f!Ie
private String countType; XF$C)id2p
int countId; q
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/** Creates a new instance of CountData */ 4* hmeS"
public CountBean() {} JuI,wA
public void setCountType(String countTypes){ nz&JG~Qfm
this.countType=countTypes; Ek.j@79
} &\K#UVDyhh
public void setCountId(int countIds){ tr} $82Po
this.countId=countIds; sR0nY8@F
} Stw6%T-
public String getCountType(){ U5PCj ]-Xt
return countType; /kq~*s
} >) ^!gz8
public int getCountId(){ Zn!SHj
return countId; cK } Qu
} t8[:}[Jx
} 0&-sz=L
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CountCache.java ]_,~q@r$
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/* Vqr&)i"b$
* CountCache.java }A;Xd/,'r
* h 2zCX
* Created on 2007年1月1日, 下午5:01 !1_:n D
* 3N21[i2/m
* To change this template, choose Tools | Options and locate the template under M>#{~zr
* the Source Creation and Management node. Right-click the template and choose tpD?-`9o
* Open. You can then make changes to the template in the Source Editor. L$Q+R'
*/ BkF[nL*|
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package com.tot.count; V]2z5u_q
import java.util.*; \NqC i'&
/** gs3}rW
* $} Myj'`r
* @author 6M9rC[h\
*/ .wSAysiQ|P
public class CountCache { L5W>in5(
public static LinkedList list=new LinkedList(); [`lAc V<
/** Creates a new instance of CountCache */ GwULtRa/
public CountCache() {} ao!r6:&v$e
public static void add(CountBean cb){ KPhqD5,
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if(cb!=null){ ik*_,51Zj
list.add(cb); `<n:D`{dZ
} -G 'lyH
} 9vu8koL
} URgF8?n
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CountControl.java ._Xtb,p{
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/* :S12=sFl$
* CountThread.java A@OV!DJe]
* l?o-
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* Created on 2007年1月1日, 下午4:57 O)R0,OPb
* cw.7YiU
* To change this template, choose Tools | Options and locate the template under ?s]`G'=>V`
* the Source Creation and Management node. Right-click the template and choose $5r,Q{;$
* Open. You can then make changes to the template in the Source Editor. fna>>
*/ !*gAGt_
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package com.tot.count; YP,PJnJU8
import tot.db.DBUtils; t,,^^ll
import java.sql.*; Cj+=9Dc
/** v_0!uT5~NE
* l0{DnQA>I
* @author ltR^IiA}
*/ xF;v 6d
public class CountControl{ 8B/9{8
private static long lastExecuteTime=0;//上次更新时间 Rjl __90
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 z%tu6_4j
/** Creates a new instance of CountThread */ . $YF|v[=
public CountControl() {} 6,1|y%(f
public synchronized void executeUpdate(){ [)~@NN
Connection conn=null; us%RQ8=k
PreparedStatement ps=null; ,IE0+!I
try{ Ui!|!V-
conn = DBUtils.getConnection();
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conn.setAutoCommit(false); `F 8;{`a
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); S45>f(!
for(int i=0;i<CountCache.list.size();i++){ "lf3hWGw
CountBean cb=(CountBean)CountCache.list.getFirst(); 9G+rxyWMW
CountCache.list.removeFirst(); =osw3"ng
ps.setInt(1, cb.getCountId()); V&v~kzLr+
ps.executeUpdate();⑴ Q0\5j<'e
//ps.addBatch();⑵ GuvF
} +Uq:sfj,
//int [] counts = ps.executeBatch();⑶ LB7I`W
conn.commit(); &Ld8Z9IeFp
}catch(Exception e){ ^\jX5)2{
e.printStackTrace(); PSS/JFZ^
} finally{ '/g+;^_cB
try{ 4ZpF1Zc4B
if(ps!=null) { Zb;$ZUWQX
ps.clearParameters(); *%'7~58ObS
ps.close(); '<S:|$$
ps=null; \3?;[xD
} }p?V5Qp
}catch(SQLException e){} 9?chCO(@
DBUtils.closeConnection(conn); WV"QY/e3
} }AZx/[k
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} ]},Q`n>$
public long getLast(){ kTc5KHJ7
return lastExecuteTime; 9XvM%aHs:
} n4T2'e
public void run(){ cG!2Iy~lA
long now = System.currentTimeMillis(); F6]!?@
if ((now - lastExecuteTime) > executeSep) { #'J7Wy
//System.out.print("lastExecuteTime:"+lastExecuteTime); :k(t/*Nl3
//System.out.print(" now:"+now+"\n"); iiB )/~!O
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); lY9M<8g
lastExecuteTime=now; b(-t)5^}
executeUpdate(); >@"3Q`
} rRrW
else{ o+Ti$`2<O7
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ;}jbdS3
} #s
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} &t|V:_?/x
} _QUu'zJ
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 ?WtG|w
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类写好了,下面是在JSP中如下调用。 A+1]Ql)$
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<% vJAAAS
CountBean cb=new CountBean(); EJ;0ypbG
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); f(s3TLM
CountCache.add(cb); Fif^V
out.print(CountCache.list.size()+"<br>"); 5QFXj)hR+4
CountControl c=new CountControl(); eTRx 6Fri(
c.run(); Vt)\[Tl~
out.print(CountCache.list.size()+"<br>"); p2c=;5|/Q
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