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: #Rcb
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CountBean.java j]'7"b5
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/* 6Z3L=j
* CountData.java 1US4:6xX_
* $UGX vCR
* Created on 2007年1月1日, 下午4:44 #Z]l4d3{T
* K_sHZ
* To change this template, choose Tools | Options and locate the template under "xKykSk
* the Source Creation and Management node. Right-click the template and choose ?B~S4:9
* Open. You can then make changes to the template in the Source Editor. z<9wh2*M
*/ bs=x>F
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package com.tot.count; [GqQ6\
hMvLx>q3)
/** KN-)m ta&
* E1-BB
* @author m3i+b
*/ ]3iQpL
public class CountBean { i917d@r( <
private String countType; G :JQ_w
int countId; Dq G m
/** Creates a new instance of CountData */ Ga1(T$|H
public CountBean() {} ' (1`iQ;
public void setCountType(String countTypes){ iy\ 6e k1
this.countType=countTypes; .~t.B!rVSB
} {gwJ>]z"e
public void setCountId(int countIds){ Xe7/
this.countId=countIds; (Ld,<!eN0
} 0<C]9[l
public String getCountType(){ &@h(6
return countType; V*1hoC#
} aBonq]W
public int getCountId(){ ;Wu6f"+Y#
return countId; )UgLs|G~
} ~SN *
} ^\ocH|D
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CountCache.java 1Vy8TV3D
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/* osdl dS
* CountCache.java tlJ@@v&=
* 7)#8p@Q
* Created on 2007年1月1日, 下午5:01 jZ\a:K?
* Qaeg3f3F3
* To change this template, choose Tools | Options and locate the template under .Do(iYO.L
* the Source Creation and Management node. Right-click the template and choose `8sC>)lrwu
* Open. You can then make changes to the template in the Source Editor. ]d]rV
`RF
*/ nA?Ks!9T
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package com.tot.count; @nOj6b
import java.util.*; vlS+UFH0
/** O4.`N?Xq
* 9`X}G`
* @author 7`_`V&3s
*/ :[C"}mR1
public class CountCache { p.|NZXk%%a
public static LinkedList list=new LinkedList(); V>Vu)7
/** Creates a new instance of CountCache */ X&14;lu%p
public CountCache() {} y}bliN7;1e
public static void add(CountBean cb){ JRYCM}C]
if(cb!=null){ Yfd0Np~
list.add(cb); #Li6RSeW
} <*F!A' w2o
} v%$c_'d
} Q^!x8oUF
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CountControl.java @&xWd{8'
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/* QDdH5EfY
* CountThread.java gql^Inx<
* x^]J^L45
* Created on 2007年1月1日, 下午4:57 vnS;T+NZSC
* 3F ]30
* To change this template, choose Tools | Options and locate the template under qb1JE[2F
* the Source Creation and Management node. Right-click the template and choose e=u?-8
* Open. You can then make changes to the template in the Source Editor. %;MM+xVVX
*/ |Jpi|'
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package com.tot.count; w1J%%//(h
import tot.db.DBUtils; <A`zK
import java.sql.*; V+Y;
/** fDD^?/^
* ;:A/WU.^
* @author 3s
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*/ .TpM3b#r
public class CountControl{ /=IBK`
private static long lastExecuteTime=0;//上次更新时间 jH~VjE>
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 IJ E{JH
/** Creates a new instance of CountThread */ H05xt$J
public CountControl() {} % db
public synchronized void executeUpdate(){ DT#F?@LG(
Connection conn=null; m:x<maP#E
PreparedStatement ps=null; mP[Z lS~"
try{ z=1N}l~|*
conn = DBUtils.getConnection(); Zv&<r+<g
conn.setAutoCommit(false); Mv\]uAT`
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); *aaK_=w
for(int i=0;i<CountCache.list.size();i++){ &r0U9J
CountBean cb=(CountBean)CountCache.list.getFirst(); M>g%wg7Ah
CountCache.list.removeFirst(); X 3q2XU
ps.setInt(1, cb.getCountId()); ~A$y-Dt'
ps.executeUpdate();⑴ _y5J]Yu`j
//ps.addBatch();⑵ ^={s(B2
}
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//int [] counts = ps.executeBatch();⑶ f{+n$Cos
conn.commit(); g?OC-zw
}catch(Exception e){ 7+;CA+;
e.printStackTrace(); /k^!hI"4c
} finally{ WinwPn+9
try{ ?w5>Z/V
if(ps!=null) { (t_%8Eu
ps.clearParameters(); B6J<
ps.close(); >& `;@ZOH
ps=null; 94Q?)0W$
} U#>K(
}catch(SQLException e){} 'Hv=\p4$1
DBUtils.closeConnection(conn); :TkR]bhm
} y^[?F>wB
} wzf%~ats
public long getLast(){ L <W2a(
return lastExecuteTime; &<oJw TC
} ywY[g{4+
public void run(){ |!hN!j*)
long now = System.currentTimeMillis();
+
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if ((now - lastExecuteTime) > executeSep) {
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-
//System.out.print("lastExecuteTime:"+lastExecuteTime); !cNw8"SIU
//System.out.print(" now:"+now+"\n"); 1)v]<Ga~%1
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); B
x-"<^<
lastExecuteTime=now; W!B\VB
executeUpdate(); w
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} /v8yE9N_
else{ oxZXY]$y
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); kG>m(n
} wrm
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} W'" p:Uhq
} B0$ge"FK9
//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 UiQF4Uc"
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类写好了,下面是在JSP中如下调用。 uq\[^
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<% $iMbtA5aQ
CountBean cb=new CountBean(); EK2mJCC|
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Aq;WQyZ2
CountCache.add(cb); 'y%*W:O
out.print(CountCache.list.size()+"<br>"); jeWI<ms
CountControl c=new CountControl(); 5fY7[{2
c.run(); SL5QhP
out.print(CountCache.list.size()+"<br>"); fjh,e
%>