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: a0 qj[+
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CountBean.java sv@}x[L
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/* ,rXW`7!2
* CountData.java bu;vpNa
* ]Px:d+wX:
* Created on 2007年1月1日, 下午4:44 ~O8]3+U
* y^3,X_0
* To change this template, choose Tools | Options and locate the template under |]I#CdO
* the Source Creation and Management node. Right-click the template and choose ,d5ia4\K
* Open. You can then make changes to the template in the Source Editor.
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*/ S~}$Ly@
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package com.tot.count; Mg&HRE
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/** 8`6
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* ^g\h]RD}
* @author -)<JBs>
*/ WGluZhRuT3
public class CountBean { N:5b1TdI,
private String countType; WI%zr2T
int countId; V.+DP
/** Creates a new instance of CountData */ rC=f#YjR
public CountBean() {} -B",&yTV
public void setCountType(String countTypes){ XPrY`,kN
this.countType=countTypes; Fv<]mu
} *%;6P5n%
public void setCountId(int countIds){ H#_}^cGPR=
this.countId=countIds; G6f%/m`
} S".owe$\
public String getCountType(){ YstXNN4
return countType; 3huzz<n3
} N IO;
public int getCountId(){ ">03~:oA
return countId; x[zKtX
} Id; mn}+~
} RiwEuY
J*/$ywI
CountCache.java ;I[.
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/* P^i6MZ?
* CountCache.java l^)o'YS y
* HdDo
* Created on 2007年1月1日, 下午5:01 rAtai}Lx
* w}fqs/)w
* To change this template, choose Tools | Options and locate the template under 5B_-nYJDt
* the Source Creation and Management node. Right-click the template and choose -(`K7T>D.
* Open. You can then make changes to the template in the Source Editor. :+kg4v&r
*/ 6f<*1YR
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package com.tot.count; @w+WLeJ$40
import java.util.*; Z{Lmd`<w`j
/** ~]jx+6k]
* f'8B[&@L
* @author i+kFL$N
*/ \>&@lA
public class CountCache { V7qCbd^>XJ
public static LinkedList list=new LinkedList(); q=(M!9cE
/** Creates a new instance of CountCache */ t"jIfU>'a/
public CountCache() {} o%y+Y;|?J
public static void add(CountBean cb){ bL6L-S
if(cb!=null){ ufHuI*
list.add(cb); d{vc
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} nI((ki}v
} $yP'k&b!
} +ytT)S
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CountControl.java h'z+8X_t
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/* v)X[gt
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* CountThread.java +-xSuR,
* '` BjRg57]
* Created on 2007年1月1日, 下午4:57 +Y_Q?/M@8
* :..E:HdYO
* To change this template, choose Tools | Options and locate the template under ljaAB+
* the Source Creation and Management node. Right-click the template and choose /@xr[=L
* Open. You can then make changes to the template in the Source Editor. hnM9-hqm
*/ TPN:cA6[c
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package com.tot.count; 8+@1wks
import tot.db.DBUtils; Jv '3](
import java.sql.*; z/Mhu{ttL
/** 9P,A
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* oRtY?6^$
* @author bqf]$}/8k
*/ _"FbjQ"
public class CountControl{ ==r?
private static long lastExecuteTime=0;//上次更新时间 t6! p\Y}}
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 tIg CF?
/** Creates a new instance of CountThread */ $Sc08ro
public CountControl() {} M4L~bK
public synchronized void executeUpdate(){ 83p$!8]u
Connection conn=null; s~IA},F,\
PreparedStatement ps=null;
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try{ g(z#h$@S
conn = DBUtils.getConnection(); ^"6D0!'N
conn.setAutoCommit(false); 7k[`]:*o
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); =]2RC1#}e
for(int i=0;i<CountCache.list.size();i++){ +w_MSj#P
CountBean cb=(CountBean)CountCache.list.getFirst(); J"a2
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CountCache.list.removeFirst(); @5dBb+0J
ps.setInt(1, cb.getCountId()); kOlI?wc
ps.executeUpdate();⑴ P5ESrZ@f
//ps.addBatch();⑵ VygXhh^7\
} [|m>vY!
//int [] counts = ps.executeBatch();⑶ &})4?5
conn.commit(); _mI:Lr#dT
}catch(Exception e){ Y`[HjS,
e.printStackTrace(); (<AM+|
} finally{ { 8|Z}?I
try{ _Oaso >
if(ps!=null) { ]ZU:%Qhu
ps.clearParameters(); KY(l<pm
ps.close(); }hObtAS
ps=null; (pRy1DH~
} Rzn 0-cG
}catch(SQLException e){} 8gu7f;H/k
DBUtils.closeConnection(conn); #7cf 8y
} M7cI$=G
} '6Z/-V4k
public long getLast(){ Xbsj:Ko]]U
return lastExecuteTime; K_w0+oY a
} *6\`A!C
public void run(){ /hA}9+/
long now = System.currentTimeMillis(); =c5 /cpZ^
if ((now - lastExecuteTime) > executeSep) { D=pI'5&
//System.out.print("lastExecuteTime:"+lastExecuteTime); XQ4^:3Yc
//System.out.print(" now:"+now+"\n"); v=yI#5
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); u0 'pR#
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lastExecuteTime=now; .-1{,o/&Q
executeUpdate(); !MG>z\:
} 8t^;O!
else{ +'YSpJ
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ZCOuv6V+
} Vms7
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} a\HtxR8L
} H?zCIue3
//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 {H7$uiq3:B
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类写好了,下面是在JSP中如下调用。 BR0p0%
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<% A)`fD
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CountBean cb=new CountBean(); ED =BZR
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 6u]OXPA|
CountCache.add(cb); 80l3.z,:
out.print(CountCache.list.size()+"<br>"); vCH v
CountControl c=new CountControl(); s"^YW+HMb
c.run(); qT-nD}
out.print(CountCache.list.size()+"<br>"); yrvSbqR
%>