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: }3
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CountBean.java ](c[D9I!8
//*>p
/* fXCx!3m
* CountData.java l}B,SkP^
* HI6;=~[
* Created on 2007年1月1日, 下午4:44 k @'85A`
* K~8;wDN`b
* To change this template, choose Tools | Options and locate the template under cU7 c}?J<
* the Source Creation and Management node. Right-click the template and choose *+TIF"|1
* Open. You can then make changes to the template in the Source Editor. 99 /fI
*/ fdP[{.$?(
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package com.tot.count; "pTyQT9P
HT7V} UiaO
/** \:ntqj&A|
* NidG|Yg~Z
* @author Fn0Rq9 /@
*/ 4h wUH
public class CountBean { Z|+SC \Y
private String countType; Av[L,4A
int countId; $>zLa_cn|
/** Creates a new instance of CountData */ -#T?C]}
public CountBean() {} sxcpWSGA^
public void setCountType(String countTypes){ 44axOk!G[/
this.countType=countTypes; 2)(P;[m^o
} FRpTYLA2
public void setCountId(int countIds){ Qk?;n F
this.countId=countIds; >AIkkQT
} ilL] pU-
public String getCountType(){ b6BeOR*ps
return countType; Xao
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} [|<2BQX
public int getCountId(){ w8i"-SE
return countId; $'!r/jV
} |KFRC)g
} F aO=<jYi
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CountCache.java :{NvBxc[
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/* HH/bBM!
* CountCache.java -Gjz;/s%XH
* xFcJyjo^z
* Created on 2007年1月1日, 下午5:01 Qm86!(eZ-
* xv;'27mUt
* To change this template, choose Tools | Options and locate the template under 7+';&2M)n~
* the Source Creation and Management node. Right-click the template and choose %|md0
* Open. You can then make changes to the template in the Source Editor. dX|(n.}
*/ |4NH}XVYJ>
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package com.tot.count; tEP~`$9
import java.util.*; *ZP$dQ
/** 1B+uv0lA
* a&b75.-
* @author 3n-~+2l
*/ :X7"fX
public class CountCache { !ckmNE0
public static LinkedList list=new LinkedList(); I g*68M<
/** Creates a new instance of CountCache */ 3>%oGbo
public CountCache() {} j8kax/*[
public static void add(CountBean cb){ f,{O%*PUA
if(cb!=null){ {w*5uI%%e
list.add(cb); `?)ivy>\:
} $OMTk
} Lk{ES$
} b,U"N-6
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CountControl.java A?I/[zkc
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/* (izGF;N+
* CountThread.java 6}bUX_!&s
* D0Cs
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* Created on 2007年1月1日, 下午4:57 --*Jv"/0
* PScq-*^
* To change this template, choose Tools | Options and locate the template under F&?&8.
* the Source Creation and Management node. Right-click the template and choose 2L}F=$zz
* Open. You can then make changes to the template in the Source Editor. 8nn%wps
*/ KICy!
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package com.tot.count; e@[9WnxYe
import tot.db.DBUtils; R$qp3I
import java.sql.*; ?`R;ZT)U-
/** RK%N:!fq=
* /.!ytHw8
* @author 3Z.<=D
*/
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public class CountControl{ >
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private static long lastExecuteTime=0;//上次更新时间 -olD!zKS
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 bs{i@1$
/** Creates a new instance of CountThread */ w\wS?E4G
public CountControl() {} ;Y<Hi\2oy
public synchronized void executeUpdate(){ 2xy
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Connection conn=null; *xY}?vSs
PreparedStatement ps=null; xD[O8vQE
try{ bF'Y.+"dr
conn = DBUtils.getConnection(); 1&\ A#
conn.setAutoCommit(false); U/2]ACGCN^
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); uLok0"}
for(int i=0;i<CountCache.list.size();i++){ @lvvI<U
CountBean cb=(CountBean)CountCache.list.getFirst(); cs0;:H*N*
CountCache.list.removeFirst(); t[>y=89
ps.setInt(1, cb.getCountId()); "[W${q+0x
ps.executeUpdate();⑴ 72J@Dc
//ps.addBatch();⑵ QU0FeGtz
} alu3CE
//int [] counts = ps.executeBatch();⑶ Qoa gy L
conn.commit(); 2flgfB}2k
}catch(Exception e){ jhs('n,
e.printStackTrace(); !V|%n(O"
} finally{ )tc"4lp-
try{ cWG>w6FI
if(ps!=null) { xqV>m
ps.clearParameters(); zMZP3
xir
ps.close(); 8WT^ES~C
ps=null; Ur^~fW1o
} 3=r#=u5z
}catch(SQLException e){} a>w@9
DBUtils.closeConnection(conn); Snm
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} a~#MMl
} \1k(4MWd
public long getLast(){ jkz.qo-%
return lastExecuteTime; >cVEr+r9t
} +n#kpi'T
public void run(){ QL_~E;U
long now = System.currentTimeMillis(); i:8g3|JfMe
if ((now - lastExecuteTime) > executeSep) { '3B\I#
//System.out.print("lastExecuteTime:"+lastExecuteTime); ]#)1(ZE
//System.out.print(" now:"+now+"\n"); Yc5{M*w
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); W*D]?hXU;
lastExecuteTime=now; -Fi{[%&u
executeUpdate(); JPeZZ13sS
} 9wR-0E
)
else{ p1zT]
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ^Kvbpi,
} v4X\LsOP
} l# -4}95
} j2oHwt6"
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 *{3&?pxx
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类写好了,下面是在JSP中如下调用。 ;'^5$q
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<% bf~gWzA
CountBean cb=new CountBean(); cQ:Y@f 9
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); z5~{WAAI
CountCache.add(cb); k-o(Q"[ '
out.print(CountCache.list.size()+"<br>"); l)JNNcej
CountControl c=new CountControl(); K|"97{*|2
c.run(); &``dI,NC
out.print(CountCache.list.size()+"<br>"); 4Ji6B)B
%>