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: Fwm{oypg%
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CountBean.java % )i?\(/
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/* T,TKt%
* CountData.java _$9<N5F.,o
* 13'tsM&
* Created on 2007年1月1日, 下午4:44 N|h`}*:x=
* y9=/kFPRm
* To change this template, choose Tools | Options and locate the template under QG4#E$c
* the Source Creation and Management node. Right-click the template and choose oi::/W|A+
* Open. You can then make changes to the template in the Source Editor. p6A"_b^
*/ ZgcA[P
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package com.tot.count; 5Q?7 xTQ
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/** +s
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* I8Y[d$z
* @author 2(\~z@g
*/ wbUpD(
public class CountBean { `-hFk88
private String countType; ;E,%\<
int countId; H/|Mq#K
/** Creates a new instance of CountData */ "e&S*8QhM
public CountBean() {} k =ru)
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public void setCountType(String countTypes){ #]_S{sO
this.countType=countTypes;
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} ";J1$a
public void setCountId(int countIds){ 7;dV]N
this.countId=countIds; fM]zD/ g
} >dUnk)7
public String getCountType(){ B;SYO>.W
return countType; u#/Y<1gn
} %F3M\)jU
public int getCountId(){ $"!"=v%B
return countId; *S~gF/*kP
} $Dxz21|P7
} h:Q*T*py
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CountCache.java eRWTuIV6
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/* <*i
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* CountCache.java 1ZJP.T`
* exiCy1[+
* Created on 2007年1月1日, 下午5:01 ' &^:@V
* Eyxw.,rB/
* To change this template, choose Tools | Options and locate the template under K=;z&E=<c
* the Source Creation and Management node. Right-click the template and choose a-MDZT<xA+
* Open. You can then make changes to the template in the Source Editor. V44IA[
*/ w6F4o;<PR
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package com.tot.count; 1 xm8w$%
import java.util.*; *T$`5|
/** +?),BRCce
* 21O!CvX
* @author WtN o@e'
*/ ;dPyhR
public class CountCache { 7{
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public static LinkedList list=new LinkedList(); ,P3nZ
/** Creates a new instance of CountCache */ EEEYNu/4/
public CountCache() {} ^%@(>:)0
public static void add(CountBean cb){ il(dVW
if(cb!=null){ c`yLn%Of%
list.add(cb); 'JsP9>)
} >)YaWcI
} *)gbKXb
} E?l_*[G
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CountControl.java ycg5S rg
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/* h2#G
* CountThread.java 4yW9}=N!
* h.gj4/g
* Created on 2007年1月1日, 下午4:57 `PXSQf
* f}PT3
* To change this template, choose Tools | Options and locate the template under %>_ZUu3M
* the Source Creation and Management node. Right-click the template and choose .S>:-j'u
* Open. You can then make changes to the template in the Source Editor. 1@JAY!yoo_
*/ I'{-T=R-q
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package com.tot.count; IGeXj%e
import tot.db.DBUtils; (, Il>cR4
import java.sql.*; .uG|Vq1v
/** l`G .lM(
* 7E*d>:5I
* @author R=yn4>I
*/ `rzgC \
public class CountControl{ v_3r8My-
private static long lastExecuteTime=0;//上次更新时间 GD<xmuo
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 &k*sxW'
/** Creates a new instance of CountThread */ PE4#dx^
public CountControl() {} :8cp]vdW
public synchronized void executeUpdate(){ i1e|UR-wl
Connection conn=null; bnt>j0E
PreparedStatement ps=null; y=_8ae}aD~
try{ Q%o:*(x[O
conn = DBUtils.getConnection(); *~~ >?
conn.setAutoCommit(false); PTfTT_t
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); o(Yj[:+m
for(int i=0;i<CountCache.list.size();i++){ .Xnw@\k'
CountBean cb=(CountBean)CountCache.list.getFirst(); }ac0}
CountCache.list.removeFirst(); O>9+tQ
ps.setInt(1, cb.getCountId()); 3e+ Ih2
ps.executeUpdate();⑴ 48l!P(>?y
//ps.addBatch();⑵ } QVREj
} G9J+D?'hH
//int [] counts = ps.executeBatch();⑶ |Byw]\3v
conn.commit(); RwJ#G7S#
}catch(Exception e){ uH7$/
e.printStackTrace(); FvQ>Y')R7Z
} finally{ !)~b Un
try{ 6}zargu(;
if(ps!=null) { c193Or'6Y
ps.clearParameters(); OBp<A+a
ps.close(); BO)K=gl;8
ps=null; :Lu=t3#
} W9nmTz\8
}catch(SQLException e){} LxaR1E(Cc'
DBUtils.closeConnection(conn); qOAK`{b
} *Y8nea^$
} T|RW-i3
public long getLast(){ oKjQ?
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return lastExecuteTime; \6~(#y
} !8S$tk
public void run(){ zXWf($^&E
long now = System.currentTimeMillis(); 0IO#h{t
if ((now - lastExecuteTime) > executeSep) { OP>rEUtj
//System.out.print("lastExecuteTime:"+lastExecuteTime); 4d~Sn81xW
//System.out.print(" now:"+now+"\n"); </~!5x62Oy
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); VL4ErOoZ
lastExecuteTime=now; Wm_:1~
executeUpdate(); !cS
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} w ryjs!
else{ M|IR7OtLV
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); VX#4Gh,~N
} faH113nc
} fR[kjwX)<1
} qk!")t
//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 d(!W
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类写好了,下面是在JSP中如下调用。 #;,dk(URo
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<% =s3f{0G
CountBean cb=new CountBean(); JtA
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); g*]Gc%
CountCache.add(cb); }Jfi"L
out.print(CountCache.list.size()+"<br>"); Ch;C\H:X
CountControl c=new CountControl(); P(B:tg
c.run(); KtH-QQDluj
out.print(CountCache.list.size()+"<br>"); Bs7/<$9K/
%>