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: J.1ln
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CountBean.java u{{xnyl?
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/* -Y jv&5
* CountData.java G
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* bh;b`
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* Created on 2007年1月1日, 下午4:44 K^cWj_a"
* ncw?;
* To change this template, choose Tools | Options and locate the template under XB!`*vZ/<
* the Source Creation and Management node. Right-click the template and choose Oz9Mqcx
* Open. You can then make changes to the template in the Source Editor. <
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*/ ,0<F3h
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package com.tot.count; M-qxD"VtV=
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/** }^Ua
* s=%+o&B
* @author j@?[vi
*/ LN3dp?;_{
public class CountBean { 7^t(RNq
private String countType; '*LN)E>d
int countId; <}Wy;!L
/** Creates a new instance of CountData */ 8hdAXWPn
public CountBean() {} zaPR>:r0
public void setCountType(String countTypes){ Pfy;/}u^c
this.countType=countTypes;
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} u?/]"4
public void setCountId(int countIds){ oWOZ0]H1
this.countId=countIds; UQr+\ u
} %)]RM/e8
public String getCountType(){ #}?$mxME*
return countType;
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} Yb*}2
public int getCountId(){ FA,CBn5%
return countId; ,oe4*b}O=.
} 2YQ$hL ~
} L.[2l Q
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CountCache.java )qe o`4+y
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/* X_2I4Jz]6
* CountCache.java ) 'KHUa9
* Rwk|cqr
* Created on 2007年1月1日, 下午5:01 A}# Mrb
* O;"%z*g.
* To change this template, choose Tools | Options and locate the template under >[U$n.
* the Source Creation and Management node. Right-click the template and choose }_x oT9HUr
* Open. You can then make changes to the template in the Source Editor. [g_@<?zg
*/ iV=#'yY
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package com.tot.count; f5v|}gMAX
import java.util.*; %iNDRLR%I
/** IA'AA|v
* To+{9"$,
* @author WMg^W(
*/ (;3jmdJhK
public class CountCache { ]]4E)j8
public static LinkedList list=new LinkedList(); 2}AV_]]
/** Creates a new instance of CountCache */ E}u\{uY
public CountCache() {} +Xk!)Ge5E*
public static void add(CountBean cb){ Qt$Q/<8U
if(cb!=null){ FtXEudk
list.add(cb); 1C{~!=6#
} i%iU_`
} K!X8KPo
} ~i4@sz&
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CountControl.java )mU)7@!
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/* 6Jm4?ex
* CountThread.java 6lPGop]js]
*
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* Created on 2007年1月1日, 下午4:57 M;OYh
* j:#[voo7
* To change this template, choose Tools | Options and locate the template under ;Baf&xK
* the Source Creation and Management node. Right-click the template and choose IlVi1`]w
* Open. You can then make changes to the template in the Source Editor. ~kL":C>2
*/ V}*b^<2o5
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package com.tot.count; LX8vVj8K
import tot.db.DBUtils; +W}f0@#)<
import java.sql.*; {`: !=
/** XjC+kH
* YG% Zw
* @author wo/H:3^N
*/ h*Ej}_
public class CountControl{ ~ rRIWfhb
private static long lastExecuteTime=0;//上次更新时间 rpd3Rp
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 opBvx>S
/** Creates a new instance of CountThread */ +XQ6KG&
public CountControl() {} 3wK)vW
public synchronized void executeUpdate(){ J&5|'yVX
Connection conn=null; C][`Dk\D{
PreparedStatement ps=null; sx9N8T3n
try{ iU &V}p
conn = DBUtils.getConnection(); ? in&/ZrB
conn.setAutoCommit(false); I++!F,pB
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 9i"3R0HN
for(int i=0;i<CountCache.list.size();i++){ sbRg=k&Ns
CountBean cb=(CountBean)CountCache.list.getFirst(); ukN#>e+L1
CountCache.list.removeFirst(); \"5 \hX~dS
ps.setInt(1, cb.getCountId()); X:DHz0S
ps.executeUpdate();⑴ pDu~84!])
//ps.addBatch();⑵ Dv$xP)./
} i'a M#4V
//int [] counts = ps.executeBatch();⑶ )%Y$FLB
conn.commit(); Y.-i ;Mmu
}catch(Exception e){ Z*JZUbo-Q
e.printStackTrace(); xH92=t-w
} finally{ REHfk6YE
try{ }JI5,d
if(ps!=null) { |/q *Fg[f
ps.clearParameters(); R^D~ic
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ps.close(); *?c~7ru
ps=null; JAgec` T%
} ?g9CeeH*
}catch(SQLException e){} #ujcT%1G
DBUtils.closeConnection(conn); ,Qp58u2V
} .[~E}O
} sO6+L
#!
public long getLast(){ Z";o{@p
return lastExecuteTime; ;v.l<AOE
} F7mzBrz
public void run(){ 8R)*8bb
long now = System.currentTimeMillis(); 7^S &g.A
if ((now - lastExecuteTime) > executeSep) { !I:6L7HdwB
//System.out.print("lastExecuteTime:"+lastExecuteTime); <n0-zCf
//System.out.print(" now:"+now+"\n"); 55hJRm3
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); x*(pr5k
lastExecuteTime=now; dlyE2MiL:
executeUpdate(); !DLIIKO78
} W(EU*~<UC
else{ Q5baY\"9^
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); d!,V"*S
} GX(p7ZgB2
} jo+T!CUM'
} lxV>
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//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 Pf]L`haGN
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类写好了,下面是在JSP中如下调用。 bD=_44I
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<%
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CountBean cb=new CountBean(); d[jxU/.p;
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); =TU"B-*
CountCache.add(cb); u2o6EU`
out.print(CountCache.list.size()+"<br>"); =U2`]50
CountControl c=new CountControl(); 4_)@Nq
c.run(); . [*6W.X
out.print(CountCache.list.size()+"<br>"); `[[
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%>