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: Bj+S"yS
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CountBean.java kGH }[w
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/* zv|2:4H
* CountData.java u]g%@3Pn
* )1Y{Q Y}l
* Created on 2007年1月1日, 下午4:44 X@ --m6-
* ^3G{|JB!+
* To change this template, choose Tools | Options and locate the template under kYM~d07 V
* the Source Creation and Management node. Right-click the template and choose |O{m2Fi
* Open. You can then make changes to the template in the Source Editor. 272q1~&
*/ F6LH $C
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package com.tot.count; lz/8
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/** t0( A4E
* ZAW^/bo<
* @author 9#23FK
*/ 3RigzT3
public class CountBean { kC:uG0sW
private String countType; O+nEXS\rQ
int countId; jkQ*D(;p
/** Creates a new instance of CountData */ 55G+;
public CountBean() {} <3oWEm
public void setCountType(String countTypes){ L,HhbTRca
this.countType=countTypes; `A,-@`p
} #{6{TFx\
public void setCountId(int countIds){ l?\jB\,
this.countId=countIds; rbul8(1h
} Z@yW bjE7Z
public String getCountType(){ 3>3 Kwc~E
return countType; D+#E-8
} *-#&K\
public int getCountId(){ Ij 79~pn
return countId; rExnxQ<e
} -fM1nH&
} 2ElJbN#
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CountCache.java @tF\p
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/* gGR"Z]DBk
* CountCache.java *~2,/D
* OP;v bZ
* Created on 2007年1月1日, 下午5:01 zp6C3RG(
* a f6M,{F
* To change this template, choose Tools | Options and locate the template under |e=,oV"
* the Source Creation and Management node. Right-click the template and choose oF vfCrd
* Open. You can then make changes to the template in the Source Editor. ]v?@g:iE
*/ o m!!Sl 3
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package com.tot.count; c|f<u{'
import java.util.*; l\f*d6o
/** J;S
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* y3vdUauOn
* @author dR
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*/ {5A2&
public class CountCache { J.3u^~zy
public static LinkedList list=new LinkedList(); LmRy1T,act
/** Creates a new instance of CountCache */ Dxtp2wu%t
public CountCache() {} @MoKWfc
public static void add(CountBean cb){ B[qzUD*P_n
if(cb!=null){ WEAT01
list.add(cb);
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} M|VyV(f
} HsxVZ.dS
} GmK^}=frj
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CountControl.java C:GK,?!Jn'
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/* } FE>|1
* CountThread.java wDw[RW3
* N[?N5~jG
* Created on 2007年1月1日, 下午4:57 pD(j'[
* Fzm*Pz3
* To change this template, choose Tools | Options and locate the template under ;:iY) }
* the Source Creation and Management node. Right-click the template and choose 8bxfj<O,
* Open. You can then make changes to the template in the Source Editor. O8^A5,2@3>
*/ PoNi"Pv
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package com.tot.count; 6o^,@~:R
import tot.db.DBUtils; AWcLUe {
import java.sql.*; 5sdn[Tt##
/** "<6G6?sz
* P)"noG_'i
* @author X3(tuqmi
*/ a,Sw4yJ!Q
public class CountControl{ |U~<3.:m:
private static long lastExecuteTime=0;//上次更新时间 lVd^
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 *F WMn.
/** Creates a new instance of CountThread */ [m+2(I1
public CountControl() {} '-QwssE
public synchronized void executeUpdate(){ 02Y]`CXj
Connection conn=null; M\vwI"
PreparedStatement ps=null; Cmu@4j&
try{ MvuQz7M#d
conn = DBUtils.getConnection(); % BVs47g
conn.setAutoCommit(false); ysJQb~2q
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?");
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for(int i=0;i<CountCache.list.size();i++){ 4Xgg%@C
CountBean cb=(CountBean)CountCache.list.getFirst(); FSP+?((
CountCache.list.removeFirst(); eP.wOl
ps.setInt(1, cb.getCountId()); 0;hqIJcE:\
ps.executeUpdate();⑴ >f^r^P
//ps.addBatch();⑵ UMv.{iEj
} dA#Q}.*r
//int [] counts = ps.executeBatch();⑶ DP[IZC
conn.commit(); s:?SF.
}catch(Exception e){ _> f`!PlB|
e.printStackTrace(); a Ve'ry
} finally{ Q}`0W[a
~
try{ S
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if(ps!=null) { j_/>A=OD
ps.clearParameters(); ?fiIwF)
ps.close(); *jLJcb*.Ap
ps=null; z-BXd
} RW|`nL
}catch(SQLException e){} 9"NF/)_
DBUtils.closeConnection(conn); &]g}u5J!=
} -O1>|y2rU
} bNm#tmSt
public long getLast(){ ICpAt~3[M
return lastExecuteTime; oOnop-z7
} .RE:;<|w
public void run(){ 2^Eg9y'
long now = System.currentTimeMillis(); t\?ik6
if ((now - lastExecuteTime) > executeSep) { mGtdO/C#B
//System.out.print("lastExecuteTime:"+lastExecuteTime); FFl!\y*0z
//System.out.print(" now:"+now+"\n"); NYt&@Z}]
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); s0\X ^
lastExecuteTime=now; ? 8)'oMD
executeUpdate(); `V=N*hv`
} neB\q[k
else{ 6q*9[<8
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ;i8g41qjF
} k\wW##=v
} "76]u)
} <W|3\p6
//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 cq5jP Z}
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类写好了,下面是在JSP中如下调用。 ;}7Rjl#
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<% "K ~
CountBean cb=new CountBean(); k;2GEa]w
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); wZG\>9~
CountCache.add(cb); FI[A[*fi
out.print(CountCache.list.size()+"<br>"); 3Q"<<pi!~
CountControl c=new CountControl(); lun#^ J
c.run(); pSoiH<33
out.print(CountCache.list.size()+"<br>"); +GG9^:<yr
%>