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: nWfOiw-t
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CountBean.java (u+3{Eb
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/* &[}bHX/
* CountData.java a1_7plg
* +HQX]t:Y
* Created on 2007年1月1日, 下午4:44 %vDN{%h8
* aRdzXq#x
* To change this template, choose Tools | Options and locate the template under |vw0:\/H
* the Source Creation and Management node. Right-click the template and choose Dx/BxqG6}_
* Open. You can then make changes to the template in the Source Editor. (\>3FwFHW|
*/ v{"$:Z
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package com.tot.count; MJd!J]E6
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/** %Iw6oG
* <<W{nSm#
* @author T$)&8"Xya
*/ +Fp8cT=1
public class CountBean { Fx*iAH\e
private String countType; d:.S]OI0
int countId; x}$SB%9/
/** Creates a new instance of CountData */ Ly0^ L-~|
public CountBean() {} ) RS*MEgA
public void setCountType(String countTypes){ qI"Xh"
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this.countType=countTypes; bf|s=,D
} Stq&^S\x69
public void setCountId(int countIds){ qR/~a
this.countId=countIds; DpH+lpC
} \3LP@;Phn
public String getCountType(){ `+[Ct08
return countType; Z1
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} $'}rBPA/
public int getCountId(){ -'r4@='6}
return countId; :3J,t//c
} @9lV~,,U
} 9AO`Zk{/Ez
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CountCache.java O%L]*vIr
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/* w{l}(:xPp
* CountCache.java |*ss`W7F,2
* 6e0tA ()F
* Created on 2007年1月1日, 下午5:01 y_boJ
* L_3Ao'SA
* To change this template, choose Tools | Options and locate the template under $L7Z_JD5
* the Source Creation and Management node. Right-click the template and choose k ! l\|~
* Open. You can then make changes to the template in the Source Editor. tBC`(7E}
*/ v1h\
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package com.tot.count; \9j +ejGf
import java.util.*; (Ild>_Tdb`
/** 2CcUClP$
* gb+iy$o-
* @author ICAp
*/ Z;Q2tT/F
public class CountCache { _ p%=RIR
public static LinkedList list=new LinkedList(); uF,F<%d
/** Creates a new instance of CountCache */ "159Q
public CountCache() {} wV8_O)[
public static void add(CountBean cb){ fUj[E0yOF
if(cb!=null){ dt&m YSZ}
list.add(cb); (7Su{tq
} P/i{_r
} hOZ:r =%
} O*0%AjT6
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CountControl.java '.
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/* 'u@,,FFz[K
* CountThread.java gQ90>P:
* >NLG"[\
* Created on 2007年1月1日, 下午4:57 rlxZ,]ul
* w5fVug/;P
* To change this template, choose Tools | Options and locate the template under #uTNf78X
* the Source Creation and Management node. Right-click the template and choose _L?MYkD
* Open. You can then make changes to the template in the Source Editor. (D2G.R\pr
*/ S$#"bK/p^
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package com.tot.count; ?APzb4f^W
import tot.db.DBUtils; FZL"[3
import java.sql.*; Gak@Z!|
/** X83,fCCl5
* O2x bHn4
* @author 3dO~Na`S
*/ uoJ@Jt'j
public class CountControl{ K0;caqE^
private static long lastExecuteTime=0;//上次更新时间 g0({$2Q7R
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ;wGoEN
/** Creates a new instance of CountThread */ 6%yt"XmT
public CountControl() {} E8X(AZ 2
public synchronized void executeUpdate(){ D6+^Qmu"p
Connection conn=null; X~UrAG}_
PreparedStatement ps=null; 5&)T[Q X`
try{ B&fH
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conn = DBUtils.getConnection(); ^wass_8
conn.setAutoCommit(false); `JQw]\f4>
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); i~Q nw-^B
for(int i=0;i<CountCache.list.size();i++){ M./1.k&@
CountBean cb=(CountBean)CountCache.list.getFirst(); /{6&99SJcc
CountCache.list.removeFirst(); l,fwF ua
ps.setInt(1, cb.getCountId()); &{4KymB:
ps.executeUpdate();⑴ Q|KD$2rB
//ps.addBatch();⑵ /]U),LbN
} {L'uuG\9U
//int [] counts = ps.executeBatch();⑶ 3~q#P
conn.commit(); /1@py~ZX
}catch(Exception e){ !NqLBrcv 0
e.printStackTrace(); cr,fyAvX
} finally{ K<wg-JgA
try{ &/m0N\n?
if(ps!=null) { "+XF'ZO
ps.clearParameters(); kz0pX-@b
ps.close(); #,[z}fq
ps=null; m@Hg:DY
} O0l1AX"
}catch(SQLException e){} Kz~E"?
DBUtils.closeConnection(conn); C6"{-{H
} i[Qq,MmC
} / jLb{Ky
public long getLast(){ !LR9}Xon
return lastExecuteTime; JU Xo3D~
} dzk1 !yy
public void run(){ U8S<wf&
long now = System.currentTimeMillis(); t
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if ((now - lastExecuteTime) > executeSep) { lvOM1I
//System.out.print("lastExecuteTime:"+lastExecuteTime); ,_K y'B
//System.out.print(" now:"+now+"\n"); <) cJz
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); &?@gCVNO,
lastExecuteTime=now; [L>mrHqG
executeUpdate(); LbkQuq/d
} (N6=+dNY
else{ Sq]VtQ(
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); wY]ejK$0R
} `\beQ(g
} -e\OF3Td
} ]FNe&o1zX
//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 $b U.6
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类写好了,下面是在JSP中如下调用。 GX+Gqj.
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<% XqLR2d
CountBean cb=new CountBean(); G#L6;
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 63`5A3rii
CountCache.add(cb); rF$S
out.print(CountCache.list.size()+"<br>"); Aflf]G1
CountControl c=new CountControl(); y@h
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c.run(); Xv+!)j<
out.print(CountCache.list.size()+"<br>"); QVF561Yz
%>