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: I L=v[)en4
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CountBean.java hHg
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/* 6^aYW#O<Ua
* CountData.java h@~X*yLKh
* iR_Syk`G*A
* Created on 2007年1月1日, 下午4:44 B5cyX*! ?
* '; dW'Uwc
* To change this template, choose Tools | Options and locate the template under E5t+;vL~
* the Source Creation and Management node. Right-click the template and choose dbuOiZ
* Open. You can then make changes to the template in the Source Editor. &`Di cfD
*/ PHK#b.B>a8
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package com.tot.count; t?
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/** mce`1Tjw
* p)^:~ll
* @author )eFFtnu5
*/ PJYA5"}W
public class CountBean { OT&E)eR
private String countType; M$W#Q\<*#r
int countId; w.Vynb
/** Creates a new instance of CountData */ L@_">'pR
public CountBean() {} &+j^{a
public void setCountType(String countTypes){ (rG1_lUDu
this.countType=countTypes; >YBpB,WND
} `eWcp^|
public void setCountId(int countIds){ ._&lG3'
this.countId=countIds; N.G*ii\
} UjDF
public String getCountType(){ yKB[HpU-
return countType; `I>K?
} s4gNS
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public int getCountId(){ UvZ@"El
return countId; ;a3nH
} ,4Fqvg
} XeSbA
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CountCache.java ye|a#a9N
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/* {~^)-^Wt:
* CountCache.java T"H)g
* JZ%F
* Created on 2007年1月1日, 下午5:01 $vLV<
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* ,/:a77
* To change this template, choose Tools | Options and locate the template under &7T
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* the Source Creation and Management node. Right-click the template and choose fBgKX?Y
* Open. You can then make changes to the template in the Source Editor. CdDd+h8
*/ '^l^gW/|\
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package com.tot.count; ]X~g@O{>_
import java.util.*; )h0E$*
/** LZ)m](+M
* oe|e+
* @author iHn!KV
*/ i"]8Zw_D
public class CountCache { f4I#a&DO
public static LinkedList list=new LinkedList(); KF_Wu}q
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/** Creates a new instance of CountCache */ klJ[ {p
public CountCache() {} '98h<(@]
public static void add(CountBean cb){ ~{vdP=/WP
if(cb!=null){ MgQU6O<
list.add(cb); "-n%874IT
} 3> #mO}\
} 6eT'[Umx
} GWInN8.5
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CountControl.java qysa!B
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/* p RwGv
* CountThread.java UB$`;'|i
* 2rCY&8
* Created on 2007年1月1日, 下午4:57 }=hoATs
* X^D9)kel
* To change this template, choose Tools | Options and locate the template under 2-V)>98
* the Source Creation and Management node. Right-click the template and choose ;hA7<loY
* Open. You can then make changes to the template in the Source Editor. 7_40_kwJi
*/ f4k5R
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package com.tot.count; "'!%};
import tot.db.DBUtils; Dw`m>'J0
import java.sql.*; 0O#B'Uu
/** R==cz^#
* Ejms)JK+
* @author I\upnEKKzZ
*/ >_`D3@Rz
public class CountControl{ [DxefYyI
private static long lastExecuteTime=0;//上次更新时间 Z SRRlkU
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 "P'&+dH8
/** Creates a new instance of CountThread */ e:J'&r& 1
public CountControl() {} hO/5>Zv?
public synchronized void executeUpdate(){ k&A7alw
Connection conn=null; ZjZh z`
PreparedStatement ps=null; `_1(Q9Q
try{ PDt<lJU+X
conn = DBUtils.getConnection(); )J+{oB[>b
conn.setAutoCommit(false); %A62xnX
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); x$n~f:1Y
for(int i=0;i<CountCache.list.size();i++){ 7<:Wq=e!r
CountBean cb=(CountBean)CountCache.list.getFirst(); 3_MS'&M
CountCache.list.removeFirst(); V[Rrst0yo
ps.setInt(1, cb.getCountId()); +lW}ixt
ps.executeUpdate();⑴ adI!W-/R:
//ps.addBatch();⑵ $%
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} qo6LC >Qg
//int [] counts = ps.executeBatch();⑶ >&;>PZBPCO
conn.commit(); l#b|@4:I
}catch(Exception e){ +`*qlP;
e.printStackTrace(); [vWkAJ'K
} finally{ `pi-zE)
try{ t0bhXFaiE
if(ps!=null) { abo>_"9-
ps.clearParameters(); ~`2&'8
ps.close(); QtY hg$K3
ps=null; b0YiQjS6>
} .%?-As
}catch(SQLException e){} H^D
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DBUtils.closeConnection(conn); TF=k(@9J?
} *
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} ypD<2z^
public long getLast(){ z!s.9
return lastExecuteTime; +9zJlL^A%
} VW9>xVd4
public void run(){ UZje>.~?
long now = System.currentTimeMillis(); {}_ Nep/;
if ((now - lastExecuteTime) > executeSep) { oWp}O?
//System.out.print("lastExecuteTime:"+lastExecuteTime); ZU|6jI}
//System.out.print(" now:"+now+"\n"); dP$8JI{
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); )'[x)q
lastExecuteTime=now; "{A*(.
executeUpdate(); ;8*XOC;[
} *N-;V|{
else{ U~:N^Sc
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); U!&_mD#
c
} UzgA26;
} v/R[?H)
} b0@>xT
//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 b4Z`y8=
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类写好了,下面是在JSP中如下调用。 &yxNvyA[u
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<% 'tb(J3ZP
CountBean cb=new CountBean(); ;)(Sdf[P
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); e1
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CountCache.add(cb); `^7:7Wr]=
out.print(CountCache.list.size()+"<br>"); wMb)6YZs
CountControl c=new CountControl(); CmEpir{}(
c.run(); ,3Wb4so
out.print(CountCache.list.size()+"<br>"); L*g.
6+2
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