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: 810<1NP
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CountBean.java nYt\e]3
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/* ^J~A+CEf"W
* CountData.java _s-HlE?C
* G_N-}J>EP
* Created on 2007年1月1日, 下午4:44 Q1\k`J
* x$J.SbW
* To change this template, choose Tools | Options and locate the template under lc?mKW9
* the Source Creation and Management node. Right-click the template and choose 'qF3,Rw
* Open. You can then make changes to the template in the Source Editor. UAXF64w{
*/ Dke($Jr{
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package com.tot.count; nf.:5I.
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/** ka)LK@p6
* 6`baQ!xc.
* @author K[>@'P}y
*/ I<(.i!-x
public class CountBean { 3s_k>cO=
private String countType; !:O/|.+Vmf
int countId; /.kna4k
/** Creates a new instance of CountData */ j YIV^o 0
public CountBean() {} Sa?5iFg
public void setCountType(String countTypes){ PUjoi@]
this.countType=countTypes; `KJYm|@ i
} E?gu(\an@
public void setCountId(int countIds){ =Q8H]F
this.countId=countIds; jFNs=D&(
} S|q!? /jqj
public String getCountType(){ Op/79]$
return countType; vMZ7uO
} AXh3LA
public int getCountId(){ gAr`hXO
return countId; Q
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} *)`kx
} _L4<^Etfm
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CountCache.java &J^4Y!gt
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/* yXTK(<'
* CountCache.java #mRFUA
* oWx_O-_._
* Created on 2007年1月1日, 下午5:01 ^#BGA|j
* 5Q$r@&qp
* To change this template, choose Tools | Options and locate the template under 1]
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* the Source Creation and Management node. Right-click the template and choose 5&?KW)6 Rz
* Open. You can then make changes to the template in the Source Editor. Cl t5
*/ x!C8?K=|
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package com.tot.count; ]~prR?
import java.util.*; 7 7xq/c[)
/** ~3'RW0
* .L^pMU+!^
* @author GDHK.?GY
*/ Tf#2"(!
public class CountCache { 5PGlR!^
public static LinkedList list=new LinkedList(); a/QtJwIV
/** Creates a new instance of CountCache */ R81{<q'%X
public CountCache() {} 2JiAd*WK
public static void add(CountBean cb){ FJ{,=@
if(cb!=null){ U/X|i /
list.add(cb); W,HH *!
} gV"qV
} 80?6I%UB<
} r=~WMDCz@
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CountControl.java M&qh]v gC
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/* Ml8 YyF/~
* CountThread.java %@}o'=[
* L$+d.=]
* Created on 2007年1月1日, 下午4:57 #`jE%ONC
* N5 SLF4R1
* To change this template, choose Tools | Options and locate the template under +Lm3vj_N
* the Source Creation and Management node. Right-click the template and choose $J QWfGwR
* Open. You can then make changes to the template in the Source Editor. H96BqNoO
*/ ~L %Pz0Gg
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package com.tot.count; OUEI~b1
import tot.db.DBUtils; \{c,,th
import java.sql.*;
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/** FI]P<)*r
* W@I
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* @author hLb;5u&!kW
*/ aO8ch
public class CountControl{ -VS9`7k
private static long lastExecuteTime=0;//上次更新时间 9=t#5J#O
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 :s'o~
/** Creates a new instance of CountThread */ ^FP}
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public CountControl() {} /> ^@
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public synchronized void executeUpdate(){ tHrK~|
Connection conn=null; WnD^F>
PreparedStatement ps=null; A<4_DVd@@
try{
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conn = DBUtils.getConnection(); 0:Ar|to$m
conn.setAutoCommit(false); tIq>Oojdx
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); duX0Mc.0P
for(int i=0;i<CountCache.list.size();i++){ e8$l0gzaD
CountBean cb=(CountBean)CountCache.list.getFirst(); ;mEwQ
CountCache.list.removeFirst(); 9mam ~)_ |
ps.setInt(1, cb.getCountId());
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ps.executeUpdate();⑴ gRBSt
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//ps.addBatch();⑵ 6}ce1|mkg/
} _p\629`
//int [] counts = ps.executeBatch();⑶ L2KG0i`+
conn.commit(); i.3cj1
}catch(Exception e){ k@#5$Ejc2
e.printStackTrace(); 9]"S:{KSCn
} finally{ b9!.-^<8y
try{ $tI]rU
if(ps!=null) { 6yY.!HRkr
ps.clearParameters(); !RS9%ES_?
ps.close(); dXmV@ Noo
ps=null; K*~]fy
} Rj^7#,993
}catch(SQLException e){} A]7<'el=
DBUtils.closeConnection(conn); 7_-w_"X
} a Sf/4\
} !lAD
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public long getLast(){ }^9]jSq5
return lastExecuteTime; ["}A
S:
} F*M|<E=
public void run(){ S='
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long now = System.currentTimeMillis(); oK2pM18
if ((now - lastExecuteTime) > executeSep) { &-M]xo^
//System.out.print("lastExecuteTime:"+lastExecuteTime); -D^L}b
//System.out.print(" now:"+now+"\n"); +iy7e6P
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); h{k_6ym
lastExecuteTime=now; ~4\,&HH
executeUpdate(); 77V
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} 1~J5uB 4
else{ .x!T+`l>8I
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); n 6{2]&sd
} RsW9:*R
} m
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} {^5?)/<
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 JQ@fuo %
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类写好了,下面是在JSP中如下调用。 T$KF<
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<% ,`32!i
CountBean cb=new CountBean(); eWvo,4
cb.setCountId(Integer.parseInt(request.getParameter("cid")));
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*
CountCache.add(cb); H2;X
out.print(CountCache.list.size()+"<br>"); e'2Y1h
CountControl c=new CountControl(); >`'O7.R
c.run(); {fV}gR2
out.print(CountCache.list.size()+"<br>"); fr[3:2g-_
%>