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: p<2A4="&
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CountBean.java w7?&eF(w(
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/* ^nYS@
* CountData.java ",c(cYVW
* cboue
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* Created on 2007年1月1日, 下午4:44 H\\0V.}!
* $vC!Us{z
* To change this template, choose Tools | Options and locate the template under 8T:|~%Sw
* the Source Creation and Management node. Right-click the template and choose n\#RI9#\
* Open. You can then make changes to the template in the Source Editor. K>2mm!{
*/ _Kp{b"G
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package com.tot.count; s 9,?"\0Zm
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/** Efm37Kv5l
* wr/Z)e =^3
* @author )2|'`
*/ gF@51K
public class CountBean { ))"
*[
private String countType; ;hz"`{(JY
int countId; >g]S"ku|
/** Creates a new instance of CountData */ _y q"F#,*
public CountBean() {} 3d^zLL
public void setCountType(String countTypes){ e5bRi0
this.countType=countTypes; h\k!X/
} )SMS<J
public void setCountId(int countIds){ A#gmKS<J/7
this.countId=countIds; P#/k5]g
} uUUj?%
public String getCountType(){ HL;y5o?
return countType; b]v.jgD
} PK#; \Zw
public int getCountId(){ [-)N}rL>
return countId; Vd2bG4*=
} fKzOt<wm
} tN&x6O+@
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CountCache.java 3;(6tWWLT
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/* lE~5 b
* CountCache.java }(h_ztw
* Bb^CukS:
* Created on 2007年1月1日, 下午5:01 'u }|~u?m
* LXr
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* To change this template, choose Tools | Options and locate the template under -s`/5kD
* the Source Creation and Management node. Right-click the template and choose xEN""*Q
* Open. You can then make changes to the template in the Source Editor. ^EGe%Fq*x]
*/ D[2I_3[wp
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package com.tot.count; /3F4t
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import java.util.*; X\tE#c&K
/** v\>!J?
* /; ;_l2 t
* @author byl#8=?
*/ hnM?wn
public class CountCache { 1b:3'E.#w
public static LinkedList list=new LinkedList(); vA rM.Bu>b
/** Creates a new instance of CountCache */ jm1f,=R
public CountCache() {} 6eSc`t&
public static void add(CountBean cb){ 8_8r{a<xW
if(cb!=null){ 8X":,s!
list.add(cb); g9>
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} 8RJXY:%
} }D_h*9
} ~|e?@3_G
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CountControl.java OOy]:t4 /
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/* J0BA@jH5
* CountThread.java %$/t`'&o-
* QiB^U^f
* Created on 2007年1月1日, 下午4:57 q:4 51 C
* 6/^$SWd2
* To change this template, choose Tools | Options and locate the template under iaAVGgA9+
* the Source Creation and Management node. Right-click the template and choose 0e1W&
* Open. You can then make changes to the template in the Source Editor. 8?ldD
*/ q_eGY&M
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package com.tot.count; ]~g6#@l
import tot.db.DBUtils; J%d\ 7
import java.sql.*; m\>531&
/** U)~?/s{v
* w5 nzS)B:u
* @author MP/6AAt7=|
*/ CL{R.OA
public class CountControl{ J-t5kU;L{
private static long lastExecuteTime=0;//上次更新时间 XXsN)2
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 *-~B{2b<
/** Creates a new instance of CountThread */ aIV(&7KT4
public CountControl() {} tZlz0BY!
public synchronized void executeUpdate(){ *RugVH4
Connection conn=null; M)t d%<_
PreparedStatement ps=null; T|o[! @:,
try{ va \5
conn = DBUtils.getConnection(); x<#Z3Kla
conn.setAutoCommit(false); Q2sX7
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); HMyw:?
for(int i=0;i<CountCache.list.size();i++){ ?;!d5Xuu
CountBean cb=(CountBean)CountCache.list.getFirst(); UELni,$
CountCache.list.removeFirst(); <rd7<@>5D
ps.setInt(1, cb.getCountId()); i$HA@S
ps.executeUpdate();⑴ P6,~0v(S
//ps.addBatch();⑵ r|t;#
} t2Dx$vT*&
//int [] counts = ps.executeBatch();⑶ et|QW;*L
conn.commit(); Fy!uxT-\
}catch(Exception e){ Ws'OJ1
e.printStackTrace(); `6:;*#jO,
} finally{ FSZQ2*n5
try{ t]?u<KD<
if(ps!=null) { 'f0*~Wq|
ps.clearParameters(); C2RR(n=N^
ps.close(); :7ej6
ps=null; \ FW{&X9a
} 0{bGVLp
}catch(SQLException e){} ssVO+
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DBUtils.closeConnection(conn); Qhlgu!
} t5dk}sRF
} MQc|j'vEY
public long getLast(){ fpbb <Ro
return lastExecuteTime; '"C$E922
} xE(VyyR
public void run(){ q{/>hvl
long now = System.currentTimeMillis(); v'Y)~Kv@!
if ((now - lastExecuteTime) > executeSep) { pE{ZWW[@+
//System.out.print("lastExecuteTime:"+lastExecuteTime); ,H!E :k
//System.out.print(" now:"+now+"\n"); L~N<<8?\
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ]O
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lastExecuteTime=now; L}O_1+b
executeUpdate(); t}LV[bj1u
} 2\h]*x%:
else{ ~nk{\ rWO
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); .>z)6S_G
} n"YY:Gm;8
} 9-)D"ZhLe
} ]k~k6#),;
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 GtcY){7
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类写好了,下面是在JSP中如下调用。 gf/$M[H!
@QiuCB
<% ()1\b
CountBean cb=new CountBean(); Y<%)Im6v/
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ;ru=z@
CountCache.add(cb); f\+MnZ4[Qj
out.print(CountCache.list.size()+"<br>"); >r+Dl\R
CountControl c=new CountControl(); Q]WjW'Ry\
c.run(); g{K*EL<
out.print(CountCache.list.size()+"<br>"); ceN*wkGyB
%>