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: Rd&9E
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CountBean.java C"uahP[Y
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/* -.I4-6~
* CountData.java h) (*q+a
* IzLF'F
* Created on 2007年1月1日, 下午4:44 -6~' cm
* (nSml,gU
* To change this template, choose Tools | Options and locate the template under $9!D\N,}]C
* the Source Creation and Management node. Right-click the template and choose XVVD 0^ Q
* Open. You can then make changes to the template in the Source Editor. "E*e2W
*/ |}&RXD
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package com.tot.count; \1%l^dE@
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/** x34f9!
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* VRng=,
* @author OEhHR
*/ W#w.h33)#6
public class CountBean { y*b3&%.ml
private String countType; ;iYff N
int countId; u0s8yPA
/** Creates a new instance of CountData */ oDB`iiBXQ
public CountBean() {} P1>AOH2yG
public void setCountType(String countTypes){ Qt>>$3]!!
this.countType=countTypes; ?V(^YFzZ
} Bn?V9TEoO
public void setCountId(int countIds){ zU5Hb2a
this.countId=countIds; d=O3YNM:v
} ;^){|9@
public String getCountType(){ Q+q,!w8
return countType; 63WS7s"
} L,[;k
public int getCountId(){ TbVn6V'
return countId; _Q(g(p&
} G%lu28}D
} .3qu9eP
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CountCache.java is^pgKX
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/* zDOKShG
* CountCache.java h11.'Eej`
* %b2oiKSBx?
* Created on 2007年1月1日, 下午5:01 e(
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* LaMLv<)k
* To change this template, choose Tools | Options and locate the template under UL@9W6
* the Source Creation and Management node. Right-click the template and choose s,]%dG!
* Open. You can then make changes to the template in the Source Editor. X|LxV]
*/ ;QCrHqRT`
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package com.tot.count; ZAKeEm2A
import java.util.*; 6=hk=2]f
/** RIn9(r
* FqFapRX66Z
* @author cgu~
*/ h@{_duu
public class CountCache { GwU?wIIj^
public static LinkedList list=new LinkedList(); 9O*_L:4o
/** Creates a new instance of CountCache */ 8|?LN8rp
public CountCache() {} $(pF;_W
public static void add(CountBean cb){ ;
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if(cb!=null){ | t QiFC
list.add(cb); fnKY1y]2+
} :aLT0q!K
} 6.1)IQkO
} |Hr:S":9
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CountControl.java g| <wyt[
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/* R<ND=[}s
* CountThread.java &;TJ~r#K
* u6u=2
* Created on 2007年1月1日, 下午4:57 F^$led1/F
* MxQ?Sb%Gka
* To change this template, choose Tools | Options and locate the template under [4&#*@
* the Source Creation and Management node. Right-click the template and choose G_H?f\/
* Open. You can then make changes to the template in the Source Editor. #V02hs1
*/ Z;Rp+X
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package com.tot.count; SzDKByi
import tot.db.DBUtils; ?(6m VyIe
import java.sql.*; C#V ~Y
/** /Dtd#OAdr
* \VMD$zZx
* @author Ty(@+M~-
*/ 4674SzL
public class CountControl{ [Qt?W gPj
private static long lastExecuteTime=0;//上次更新时间 #L}+H!Myh
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 V
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/** Creates a new instance of CountThread */ Uh1NO&i.W
public CountControl() {} HL3XyP7
public synchronized void executeUpdate(){ /e}#'
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Connection conn=null; =QJRMF
PreparedStatement ps=null; [k$*4u>
try{ CI:^\-z
conn = DBUtils.getConnection(); o KD/rI
conn.setAutoCommit(false); m(iR|Zx
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Q:C$&-$
for(int i=0;i<CountCache.list.size();i++){ :K82sCy%5
CountBean cb=(CountBean)CountCache.list.getFirst(); ^i)hm
CountCache.list.removeFirst(); M]v=-
ps.setInt(1, cb.getCountId()); U).*q?.z
ps.executeUpdate();⑴ $*a'84-5G-
//ps.addBatch();⑵ <N,)G
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} DHC+C4
//int [] counts = ps.executeBatch();⑶ f;SC{2 f
conn.commit(); Mp$@`8X`
}catch(Exception e){ `p kMN
e.printStackTrace(); ysIh[1E~%:
} finally{ s^OO^%b
try{ n(nBRCG)o
if(ps!=null) { OYC_;CP
ps.clearParameters(); x]mxD|?f
ps.close(); ]j~"mFAP
ps=null; y)c5u%(
} ^I
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}catch(SQLException e){} }U w&Ny
DBUtils.closeConnection(conn); wu9=N
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} o'<^LYSnB
} bOp54WI-g
public long getLast(){ y7i %W4
return lastExecuteTime; FSuAjBl0-
} u}bf-;R
public void run(){ ow=UtA-^O
long now = System.currentTimeMillis(); Si9Z>MR
if ((now - lastExecuteTime) > executeSep) { L(>=BK*
//System.out.print("lastExecuteTime:"+lastExecuteTime); X;F?:Iw \
//System.out.print(" now:"+now+"\n"); 8;Fn7k_Uf
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); e}VBRvr
lastExecuteTime=now; u,3,ck!B>@
executeUpdate(); ^taBG3P
} OU4pjiLx
else{ ,vqr<H9e
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); d1@%W;qX!
} v4miU;|\
} EVX{ 7%
} vKwQXR~C
//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 Z}A%=Z\/3
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类写好了,下面是在JSP中如下调用。 wv
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<% Cd79 tu|
CountBean cb=new CountBean(); ;Yfv!\^ |
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); :4)Qt
CountCache.add(cb); qjAWeS/
out.print(CountCache.list.size()+"<br>"); /N>e&e[35\
CountControl c=new CountControl(); 1T_QX9
c.run(); h0oMTiA
out.print(CountCache.list.size()+"<br>"); >R{qESmP=
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