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: ^S|^1
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CountBean.java oJ+$&P(
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/* TbuR?#
* CountData.java gjV&X N
* 91XHz14
* Created on 2007年1月1日, 下午4:44 NU[{oI<a
* BoqW;SG$9
* To change this template, choose Tools | Options and locate the template under r%9Sx:F
* the Source Creation and Management node. Right-click the template and choose !
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* Open. You can then make changes to the template in the Source Editor. oH0\6:S
*/ )%7A. UO)
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package com.tot.count; %9.KH
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/** RT>3\qhZ
* !@X#{
* @author o_n.,=/cZ
*/ yw0uF
public class CountBean { ?`>yl4
private String countType;
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int countId; 5;l_-0=
/** Creates a new instance of CountData */ @C2<AmY9q*
public CountBean() {} E
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public void setCountType(String countTypes){ <]nI)W(
this.countType=countTypes; b4wJnmC8
} 6eD[)_?]y
public void setCountId(int countIds){ 67eo~~nUtg
this.countId=countIds; L"a#Uu8
} 4o8!p\a
public String getCountType(){ 8] *{i
return countType; ? 6l::M
} :jPAA`,
public int getCountId(){
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return countId; N\?iU8w=
} wF(FV4#gs
} BR=Yte
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CountCache.java 4\?B,!
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/* Ow
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* CountCache.java U#}.r<
* rd RX
* Created on 2007年1月1日, 下午5:01 /%7eo?@,
* 0AEs+=
* To change this template, choose Tools | Options and locate the template under aZRgd^4
* the Source Creation and Management node. Right-click the template and choose M: 6cma5
* Open. You can then make changes to the template in the Source Editor. L!Ro`6|7;
*/ D-.>Dw:
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package com.tot.count; 82vx:*Ip!}
import java.util.*; a_yV*N`D
/** i@RjG
* }bVyvH
* @author SZPu"O\
*/ ?r+tU
public class CountCache { 9HE)!Col
public static LinkedList list=new LinkedList(); SYL$?kl
/** Creates a new instance of CountCache */ ;P_Zen
public CountCache() {}
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public static void add(CountBean cb){ ]~P?
if(cb!=null){ @lX)dY
list.add(cb); 9pgct6BO
} 0[];c$r<
} =aCv
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} aE"t['
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CountControl.java !m;VWGl*
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/* l>ttxYBa<d
* CountThread.java Qi%A/~
* H{BjxZ~)
* Created on 2007年1月1日, 下午4:57 %lPP1
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* DM&"oa50
* To change this template, choose Tools | Options and locate the template under ZBGI_9wZ
* the Source Creation and Management node. Right-click the template and choose ^\!p;R
* Open. You can then make changes to the template in the Source Editor. ,-b9:]{L
*/ "`S61m_
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package com.tot.count; s|%</fMt9
import tot.db.DBUtils; SnqLF
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import java.sql.*; Cur)|
/** 6$f,DU
* qr@,92_
* @author S:d `z'
*/ Q3DxjD
public class CountControl{ b?$3jOtW
private static long lastExecuteTime=0;//上次更新时间 P'K')]D=!
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 4q[r
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/** Creates a new instance of CountThread */ V= _8G3
public CountControl() {} efhwbn
public synchronized void executeUpdate(){ $Z j.
Connection conn=null; /~yqZD<O
PreparedStatement ps=null; &jJgAZ!
try{ q\,H9/.0k
conn = DBUtils.getConnection(); T:ck/:ZH
conn.setAutoCommit(false); 5HU>o|.
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 2{&" 3dq
for(int i=0;i<CountCache.list.size();i++){ J4gIkZD
CountBean cb=(CountBean)CountCache.list.getFirst(); >3bpa<M_
CountCache.list.removeFirst(); A!J5Wz>Q5
ps.setInt(1, cb.getCountId()); Np<Aak
ps.executeUpdate();⑴ ^Z!W3q Q
//ps.addBatch();⑵ I/tzo(r
} jsR1jou6
//int [] counts = ps.executeBatch();⑶ FD*y[A
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conn.commit(); =k_u5@.Z
}catch(Exception e){ K!9=e7|P
e.printStackTrace(); m$^7sFD$
} finally{ '>6-ie^0
try{ =4I361oMf
if(ps!=null) { b{oNV-<&{
ps.clearParameters(); Y/+ D4^L
ps.close(); aX|`G]PhdI
ps=null; _Sg29qFK
} Fh"S[e
}catch(SQLException e){} ReRRFkO"2
DBUtils.closeConnection(conn); H(AYtnvB
} BZj[C=#x
} .D) }MyKnu
public long getLast(){ 1>2397
return lastExecuteTime;
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} uPqPoI>N!
public void run(){ w+}dm^X
long now = System.currentTimeMillis(); 0Zq"-
if ((now - lastExecuteTime) > executeSep) { :K&hGZ+5
//System.out.print("lastExecuteTime:"+lastExecuteTime); P.wINo
//System.out.print(" now:"+now+"\n"); l YhwV\3
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); O<Kr6+
-
lastExecuteTime=now; gW, ET
executeUpdate(); Rl(b tr1w
} l]ZUKy
else{ }YjSv^
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 0L6L_;o
} VTHDGBU
} j7W_%Yk|E
} R%Z} J R.
//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 [9L(4F20
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类写好了,下面是在JSP中如下调用。 @|^Ch+%@
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<% &a0%7ea`.S
CountBean cb=new CountBean(); F^\v`l,
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Bj2rA.M
CountCache.add(cb); brFOQU?
out.print(CountCache.list.size()+"<br>"); 6!'yU=Z`
CountControl c=new CountControl(); 6R<%.-qr
c.run(); A+p}oY '
out.print(CountCache.list.size()+"<br>"); P8EGd}2{8
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