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: WII_s|YSt%
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CountBean.java [,5clR=F
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/* .)Se-'
* CountData.java r _r$nl
* n X
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* Created on 2007年1月1日, 下午4:44 ej<z]{`05
* Smk]G))o{
* To change this template, choose Tools | Options and locate the template under )m[!HE`cZ
* the Source Creation and Management node. Right-click the template and choose PyHE>C%
* Open. You can then make changes to the template in the Source Editor. !*%3um
*/ !9o8v0ZI
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package com.tot.count; NUL~zb
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/** O!f* @
* ]?)zH:2)
* @author PJAir8
*/ }qz58]fyx
public class CountBean { ;T52aX
private String countType; .: 7h=neEW
int countId; 7*XG]=z/
/** Creates a new instance of CountData */ 3F}d,aB
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public CountBean() {} +N4h
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public void setCountType(String countTypes){ 9/s-|jD
this.countType=countTypes; *8XGo
} Y,mH ]
public void setCountId(int countIds){ sCb?TyN'n
this.countId=countIds; "<O?KO3K
} ~[9 ]M)=O0
public String getCountType(){ k5xirB_
return countType; 5o~Z>
} EoY#D'[
public int getCountId(){ w#b~R^U
return countId; TU. h
} ?qK:P
} 3!$rp- !<)
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CountCache.java 103Ik6.o
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/* Ar'5kPzY>
* CountCache.java GV[[[fu
* rbtPG=t_R
* Created on 2007年1月1日, 下午5:01 WJ9u3+
* hrAI@.Bo
* To change this template, choose Tools | Options and locate the template under Ra*9d]N@
* the Source Creation and Management node. Right-click the template and choose BLJ-'8G
* Open. You can then make changes to the template in the Source Editor. "J{,P9P6
*/ 5d4-95['_
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package com.tot.count; wOk:Q4OjL
import java.util.*; Yp
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/** |R[m&uOib
* YT:5J%"
* @author .HtDcGp
*/ 2C8M1^0:Z
public class CountCache { $K
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public static LinkedList list=new LinkedList(); zR<jZwo]#
/** Creates a new instance of CountCache */ :e9E#o
public CountCache() {} [w4z)!
public static void add(CountBean cb){ pI^n("|
if(cb!=null){ WD)[Ac[
list.add(cb); Ql V:8:H$
} ]CL70+[^9
} L]tyL)
} 6a,YxR\
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CountControl.java k<f*ns
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/* (^Ln|3iz
* CountThread.java A=3U4L
* )t.q[O`
* Created on 2007年1月1日, 下午4:57 >ab=LDoM
*
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* To change this template, choose Tools | Options and locate the template under #e0+;kBh
* the Source Creation and Management node. Right-click the template and choose jf2E{48P
* Open. You can then make changes to the template in the Source Editor. 3~S~)quwP
*/ O0I/^
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package com.tot.count; x-W0 h
import tot.db.DBUtils; C'$U1%:
j
import java.sql.*; CRf^6k_;(
/** {M$8V~8D
* %q!nTGU~
* @author @rdC/=Y[
*/ fAm2ls7c
public class CountControl{ d8K^`k+x
private static long lastExecuteTime=0;//上次更新时间 ~lL($rE
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 %$}iM<
/** Creates a new instance of CountThread */ qy]-YJZ
public CountControl() {} b13>>'BMB
public synchronized void executeUpdate(){ #*`|}_6L
Connection conn=null; 8_LDS
PreparedStatement ps=null; r#j*vO '
try{ &vn9l#\(
conn = DBUtils.getConnection(); cP
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conn.setAutoCommit(false); v;A
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); f;Dz(~hw
for(int i=0;i<CountCache.list.size();i++){ XU54skN
CountBean cb=(CountBean)CountCache.list.getFirst(); 93rE5eGs
CountCache.list.removeFirst(); 8;5/_BwMu
ps.setInt(1, cb.getCountId()); {F4:
ps.executeUpdate();⑴
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//ps.addBatch();⑵ 5-J-Tn
} ~+g5?y
//int [] counts = ps.executeBatch();⑶ YUH/tl
conn.commit(); AX)zSr Xn
}catch(Exception e){ Psv!`K
e.printStackTrace(); xWMMHIu
} finally{ kDKpuA!
try{ *SW,pHYnLb
if(ps!=null) { @PI\.y_w
ps.clearParameters(); (/M c$V
ps.close(); 6 qq7:
ps=null; Em7q@
} nZ*P:K t:
}catch(SQLException e){} nGt8u4gcP
DBUtils.closeConnection(conn); w*}9;l
} l1??b
} :)z_q!$j
public long getLast(){ :s5g6TR
return lastExecuteTime; O<hHo]jLF
} 3,[2-obmi
public void run(){ pA2U+Q@
long now = System.currentTimeMillis(); j0GI[#
if ((now - lastExecuteTime) > executeSep) { p#kC#{<nE
//System.out.print("lastExecuteTime:"+lastExecuteTime); s5pY)6)
//System.out.print(" now:"+now+"\n"); TQou.'+v
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 2*M*<p=v
lastExecuteTime=now; x\%egw
executeUpdate(); xv:?n^yt.[
} jBC9Vt;B
else{ aI<~+ ]
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 1gE`_%?K
} bm4W,
} 1mX*0>
} 1 W0; YcT]
//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 0D'Wr(U(
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类写好了,下面是在JSP中如下调用。 aPC!M4#
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<% )=D&NO67Pq
CountBean cb=new CountBean(); b>i=",i\
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); nqBuC
CountCache.add(cb); /\#5\dHj
out.print(CountCache.list.size()+"<br>"); 8syo_sC |
CountControl c=new CountControl(); @K9T )p]
c.run(); No7Q,p
out.print(CountCache.list.size()+"<br>"); Y[!a82MTzn
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