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: W"kw>JEt
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CountBean.java 1qC:3
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/* R1.sq(z`
* CountData.java @ >(u:.
* 5b#6 Y
* Created on 2007年1月1日, 下午4:44 *|HZ&}
* j/9QV
* To change this template, choose Tools | Options and locate the template under =4e=wAO(i
* the Source Creation and Management node. Right-click the template and choose p{a]pG+3
* Open. You can then make changes to the template in the Source Editor. Ys$YI{
*/ DLYZsWA,
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package com.tot.count; cU*lB!
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/** #Q3PzDfj
* RW7oL:$dt
* @author %?f:"
*/ $a^isd4
public class CountBean { qd+[ShrhqZ
private String countType; ,Us2UEWNv
int countId; >J}n@MZ
/** Creates a new instance of CountData */ -(w~LT$ "
public CountBean() {} zw:C*sY
public void setCountType(String countTypes){ 2 1~7{#
this.countType=countTypes; b%;59^4AjD
} L)lQ&z?
public void setCountId(int countIds){ V->%)d3i
this.countId=countIds; U+;>S$
} %kx
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public String getCountType(){ !&`\ LJ=j
return countType; 5$oewjLO
}
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public int getCountId(){ ChTXvkdH
return countId; ,iVPcza
} ]&:b<]K3
} u5Ny=Xm
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CountCache.java ^$IZLM?E~
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/* irsfJUr[V
* CountCache.java _;:rkC fj
* 8rwYNb.P
* Created on 2007年1月1日, 下午5:01 R|1xXDLm*E
* 0HR|aqPo
* To change this template, choose Tools | Options and locate the template under N\q)LM !M
* the Source Creation and Management node. Right-click the template and choose iS"8X#[]N
* Open. You can then make changes to the template in the Source Editor. uyNJN
*/ Vd+Q:L
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package com.tot.count; S9p?*
import java.util.*; =dM.7$6) R
/** m1-\qt-yy
* -+}5ma
* @author T;!ukGoFP
*/ \E@s_fQ]
public class CountCache { 7':f_]
public static LinkedList list=new LinkedList(); h}|6VJ@.
/** Creates a new instance of CountCache */ 1s`)yu^`v
public CountCache() {} 8lOI\-
public static void add(CountBean cb){ w,Z"W;|
if(cb!=null){ 6<Z*Tvk{C
list.add(cb); PXosFz~
} k(EMp1[:nN
} \&iil =H8!
} ]jc_=I6)
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CountControl.java -\kXH"%
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/* efjO8J[uk-
* CountThread.java $J"%I$%X=
* I1)-,/nEjg
* Created on 2007年1月1日, 下午4:57 {pDTy7!Hs
* UP;Q= t
* To change this template, choose Tools | Options and locate the template under ivzAlwP
* the Source Creation and Management node. Right-click the template and choose hOPe^e"
* Open. You can then make changes to the template in the Source Editor. d(fPECv(
*/ gF[6c`-s
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package com.tot.count; hr$Sa
import tot.db.DBUtils; ?j/kOD0
import java.sql.*; _BV`,`8}
/** QqtC`H\
* Hz?!BV0
* @author P8wy*JvT
*/ ptpW41t}^
public class CountControl{ oYz!O]j;a
private static long lastExecuteTime=0;//上次更新时间 tAqA^f*{
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ~BZXt7DE
/** Creates a new instance of CountThread */ 3ai (x1%
public CountControl() {} QCOLC2I
public synchronized void executeUpdate(){ ja[OcR-tX
Connection conn=null; -J,Q;tj
PreparedStatement ps=null; B0oxCc/'sZ
try{ <%z@
conn = DBUtils.getConnection(); 1E8H%2$ V
conn.setAutoCommit(false); S_!hsY
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 99e*]')A%
for(int i=0;i<CountCache.list.size();i++){ XFW5AP
CountBean cb=(CountBean)CountCache.list.getFirst(); 4'SaEsA~
CountCache.list.removeFirst(); HG2GZ}~^1
ps.setInt(1, cb.getCountId()); [yw%i h)
ps.executeUpdate();⑴ i&`!|X-=R
//ps.addBatch();⑵ fVe@YqNa
} AnNPTi
//int [] counts = ps.executeBatch();⑶ Y4#y34We
conn.commit(); &<au/^F
}catch(Exception e){ 9ilM@SR
e.printStackTrace(); )Zas
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} finally{ -(*nSD9
try{ vwKw?Z0%J
if(ps!=null) { [O2h-`
ps.clearParameters(); ~,ynJ]_aJB
ps.close(); ./l|8o
ps=null; .APVjqG
} }A|))Ao|
}catch(SQLException e){} Wo{K}
DBUtils.closeConnection(conn); I:#Ok+
} Is13:
} 0p-#f|ET
public long getLast(){ T2wv0sHlt
return lastExecuteTime; Z>8eD|m%2
} "B#Y-
public void run(){ A 4j<\xL
long now = System.currentTimeMillis(); 3gpo
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if ((now - lastExecuteTime) > executeSep) { c45tmul
//System.out.print("lastExecuteTime:"+lastExecuteTime); bGN
5 4{f
//System.out.print(" now:"+now+"\n"); OX+hZ<y
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 6lsL^]7
lastExecuteTime=now; W;q+, Io
executeUpdate(); Q',m{;;
}
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else{ gN?0m4[$i
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); lEHwZ<je
} /xySwSmh3
} 3 > |uF
} -Q$b7*"z(
//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 KAed!z9
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类写好了,下面是在JSP中如下调用。 Wr5 Q5s)c
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<% vU!8`x)
CountBean cb=new CountBean(); :.$"kXm^
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ?;
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CountCache.add(cb); 5`~mqqR5
out.print(CountCache.list.size()+"<br>"); IaLMWoh
CountControl c=new CountControl(); V&i2L.{G)
c.run(); .+yW%~0
out.print(CountCache.list.size()+"<br>"); R)+t]}
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