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: Rp7ntI:
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CountBean.java =L;] ;i
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/* %wcSM~w
* CountData.java :+Om]#`Vls
* :0& X^]\
* Created on 2007年1月1日, 下午4:44 k@ZLg9
* xj5;: g#!
* To change this template, choose Tools | Options and locate the template under YW u cvw&
* the Source Creation and Management node. Right-click the template and choose 4lhw3,5
* Open. You can then make changes to the template in the Source Editor. @Z>ZiU,^
*/ '52~$z#m
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package com.tot.count; o*U]v
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/** $un?0S
* EnOU?D
* @author ib{-A&
*/ N_:qRpp6i
public class CountBean { _=CZR7:O
private String countType; !aO` AC=5u
int countId; ^WBuMCe
/** Creates a new instance of CountData */ Z87_ #5
public CountBean() {} 5p.rwNE
public void setCountType(String countTypes){ 7qTE('zt
this.countType=countTypes; otggN:^Qw
} [kE."#
public void setCountId(int countIds){ gUyR_5q)8l
this.countId=countIds; !,V{zTR
} 5waKI?4F
public String getCountType(){ "HE^v_p
return countType; \+aC"#+0
} 5onm]V]
public int getCountId(){ 2^i(gaXUQ
return countId; g1t0l%_7^
} ,U(1NK8o
} i[wb0yL
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CountCache.java T)r9-wOq
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/* C z\Pp q
* CountCache.java t%F0:SH
* )iFJz/n>
* Created on 2007年1月1日, 下午5:01 /cU<hApK
* Um&(&?Xf
* To change this template, choose Tools | Options and locate the template under J9~g|5
* the Source Creation and Management node. Right-click the template and choose {e|[%reSkg
* Open. You can then make changes to the template in the Source Editor. Z+@2"%W
*/ E Cyyl
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package com.tot.count; +TXX$)3%
import java.util.*; K tNY_&xd
/** )7h$G-fe
* rRFhGQq1m
* @author D_vbSF)
*/ 'C"9QfK
public class CountCache { /Q~i~B 2j-
public static LinkedList list=new LinkedList(); 0jEL<TgC
/** Creates a new instance of CountCache */ n=[/Z!
public CountCache() {} Yk=PS[f
public static void add(CountBean cb){ BCA&mi3q
if(cb!=null){ o}ZdTf=
list.add(cb); 812$`5l
} t. ;LnrY
} ~?(N
} rS;Dmm
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CountControl.java EY tQw(!Q
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/* ^pUHKXihD
* CountThread.java >p"c>V& 8
* U*)8G
* Created on 2007年1月1日, 下午4:57 -,U3fts
* aTt12Sc
* To change this template, choose Tools | Options and locate the template under '*3h!lW1.
* the Source Creation and Management node. Right-click the template and choose kBffF@{
* Open. You can then make changes to the template in the Source Editor. j:VbrR
*/ b9l;a+]d
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package com.tot.count; fZoHf\B]{
import tot.db.DBUtils; jbAx;Xt'=M
import java.sql.*; OynXkH]0T+
/** <[-nF"Q
* pS:4CNI{
* @author o,)?!{k}
*/ <*qnY7c&N;
public class CountControl{ #?S^kM-0
private static long lastExecuteTime=0;//上次更新时间 6ZP"p<xX
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Q637N|01
/** Creates a new instance of CountThread */ `G}TG(
public CountControl() {} (=om,g}
public synchronized void executeUpdate(){ _WRFsDZ'
Connection conn=null; B\XKw'
PreparedStatement ps=null; x U4 +|d
try{ z*!%g[3I
conn = DBUtils.getConnection(); I "A_b}~*}
conn.setAutoCommit(false); H5Io{B%=
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); y2^Y/)
for(int i=0;i<CountCache.list.size();i++){ jWrj?DV,2N
CountBean cb=(CountBean)CountCache.list.getFirst(); ye,>A.
CountCache.list.removeFirst(); ~GZY 5HF
ps.setInt(1, cb.getCountId()); ++^l]8
ps.executeUpdate();⑴ MB~=f[cUnd
//ps.addBatch();⑵ ^y<<>Y'I
} 7Mg=b%IYs
//int [] counts = ps.executeBatch();⑶ ;;#qmGoE
conn.commit(); c"B{/;A
}catch(Exception e){ qm"rY\:
e.printStackTrace(); T9Nb`sbV]
} finally{ f,kZ\Ia'r
try{ 8; 0A
g
if(ps!=null) { !:q/Ye3.
ps.clearParameters(); J1C3&t}
ps.close(); ;wz^gdh;
ps=null; ww],y@da
} t.xxSU5~%
}catch(SQLException e){} x-^`~p
DBUtils.closeConnection(conn); wAf\|{Vn
} UG+d-&~Ll
} \1D<!k\S
public long getLast(){ 6WXRP;!Q
return lastExecuteTime; RBs-_o+ %
} /`wvxKX
public void run(){ t/VD31
long now = System.currentTimeMillis(); xMTKf+7
if ((now - lastExecuteTime) > executeSep) { Vl&?U
//System.out.print("lastExecuteTime:"+lastExecuteTime); DtXrWS/
//System.out.print(" now:"+now+"\n"); >\KNM@'KI
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); S4Y&
lastExecuteTime=now; :~Wrf8UQ
executeUpdate(); &$`P,i 1)
} gOSJM1Mr3
else{ aX)I3^ar
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); vHryPl+
} 2$+bJJM
} QbkLdM,S*
} D$
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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 J:CXW%\ <q
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类写好了,下面是在JSP中如下调用。 ?XrQ53
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<% dCi?SIN
CountBean cb=new CountBean(); $'BSH4~|.
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); I*{4rDt
CountCache.add(cb); + jc!5i .
out.print(CountCache.list.size()+"<br>"); Q=;U@k@>
CountControl c=new CountControl(); &"f";
c.run(); n}F&1Z
out.print(CountCache.list.size()+"<br>"); JTO~9>$ B
%>