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: b77>$[xB
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CountBean.java Izv+i*(dl
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/* W(Uu@^
* CountData.java 4#'("#R
* |K^"3`SJ
* Created on 2007年1月1日, 下午4:44 H-xFiF
* W7\&~IWub
* To change this template, choose Tools | Options and locate the template under Cb_oS4vM
* the Source Creation and Management node. Right-click the template and choose \ AC|?/sH
* Open. You can then make changes to the template in the Source Editor. KPpHwcYxT
*/ G5,~Z&}YS
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package com.tot.count; nxJee=qH
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/** !!:LJ
* wHem5E
* @author v i)%$~
*/ PccB]
public class CountBean { .?>5-od2
private String countType; dna6QV>A
int countId; Bs MuQ|!
/** Creates a new instance of CountData */ NcAp_q?
4
public CountBean() {} k3t78Qg
public void setCountType(String countTypes){ ~Wp Gf,
this.countType=countTypes; n3`&zY
} N7s'6(`=X
public void setCountId(int countIds){ x+@&(NMP5
this.countId=countIds; `+/H^
} fof2
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public String getCountType(){ }rdIUlVO\
return countType; 0iZGPe~
} kpI{KISQu
public int getCountId(){ \M"UmSB o
return countId; 4W#E`9
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} 6ITLGA
} *E~VKx1
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CountCache.java jkF8\dR
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/* j2Pn<0U
* CountCache.java Zh/Uu6
* =5sF"L;b
* Created on 2007年1月1日, 下午5:01 %G@5!|J
* YUdxG/~'
* To change this template, choose Tools | Options and locate the template under NA.1QQ;e
* the Source Creation and Management node. Right-click the template and choose 6UE(f@
* Open. You can then make changes to the template in the Source Editor. TFepxF
*/ CVi`bO 4\
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package com.tot.count; c:l]=O
import java.util.*; 3?E&}J<n
/** oR*=|B
* Oc&),ru2l
* @author rz(0:vxwA
*/ dxj*Q "K
public class CountCache { ?/JBt
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public static LinkedList list=new LinkedList(); <g9"Cr`
/** Creates a new instance of CountCache */ dP>w/$C}
public CountCache() {} IF@HzT;Q
public static void add(CountBean cb){ L;QY<b
if(cb!=null){ G5tday~3
list.add(cb); GPWr>B.{:S
} 'ho{eR@d
} g8'DoHJ*
} @S 6u9v
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CountControl.java t!_x(u
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/* o/,NG U
* CountThread.java t?^9HP1b_
* M_``'gw
* Created on 2007年1月1日, 下午4:57 OSzjK7:
* 2BzqY`O
* To change this template, choose Tools | Options and locate the template under $cVi;2$p
* the Source Creation and Management node. Right-click the template and choose 'xFYUU]#T^
* Open. You can then make changes to the template in the Source Editor. -s$<Op{s
*/
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package com.tot.count; !CjqL~
import tot.db.DBUtils; <SVmOmJ-K
import java.sql.*; ~@8+hnE]
/** =ex'22
* a)2yE,":
* @author e(1k0W4B
*/ 4B?!THjk
public class CountControl{ <E\V`g
private static long lastExecuteTime=0;//上次更新时间 PG,U6c #
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 '9J|=z9.
/** Creates a new instance of CountThread */ Xev54!619
public CountControl() {} 4%*hGh=
public synchronized void executeUpdate(){ W>spz~w%j
Connection conn=null; eFTX6XB:i
PreparedStatement ps=null; 6(sIYZ2yq
try{ v&3O&y/1v
conn = DBUtils.getConnection(); }iIbcA
conn.setAutoCommit(false); `eRLc}aP2
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); J<JBdk
for(int i=0;i<CountCache.list.size();i++){ )'q%2%Ak
CountBean cb=(CountBean)CountCache.list.getFirst(); KIL18$3J
CountCache.list.removeFirst(); |)@N-f:E
ps.setInt(1, cb.getCountId()); -PAF p3w\y
ps.executeUpdate();⑴ gY`Nr!O
//ps.addBatch();⑵ U '[?9/T
} ,2 WH/"
//int [] counts = ps.executeBatch();⑶ .9LL+d
conn.commit(); Vos?PqUi 4
}catch(Exception e){ ykq'g|
e.printStackTrace(); .V%*{eHLL
} finally{ wVi%oSfM
try{ :G'xi2bs
if(ps!=null) { ~"ONAX
ps.clearParameters(); bdV3v`
ps.close(); t ,qul4y}
ps=null; nR8]@c C
} >uHS[ _`nM
}catch(SQLException e){} F,G,b
DBUtils.closeConnection(conn); '=} Y2?(
} Ohl} X 1
} ~,}s(`~
public long getLast(){ LCQkgRs}~{
return lastExecuteTime; ~uPk
} > zL|8f
public void run(){ 7unA"9=[4V
long now = System.currentTimeMillis(); I{dl% z73
if ((now - lastExecuteTime) > executeSep) { i=QqB0
//System.out.print("lastExecuteTime:"+lastExecuteTime); +Z?[M1g
//System.out.print(" now:"+now+"\n"); q|q::q*
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); [Hcaw
lastExecuteTime=now; @)sc6
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executeUpdate(); wsg//Ec]
} FU@uH
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else{ Wp*sPZ
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); R'EW7}&
} U($^E}I2(
} GhnE>d;i
} $P?{O3:V
//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 o_yRn16
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类写好了,下面是在JSP中如下调用。 "2h5m4
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<% b*9e1/]
CountBean cb=new CountBean(); QAvWJydb
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ;]h.m)~|
CountCache.add(cb); 4]UT+'RubX
out.print(CountCache.list.size()+"<br>");
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CountControl c=new CountControl(); Qp&?L"U)2
c.run(); !b%,'f y)
out.print(CountCache.list.size()+"<br>"); ||a`fH
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