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: tiI:yq0
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CountBean.java 1 Z5:DE<
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/* x4&<Vr
* CountData.java %.
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* K/+Y9JP9
* Created on 2007年1月1日, 下午4:44 ^{3,ok*Nf
* DM3W99PWA
* To change this template, choose Tools | Options and locate the template under T(UPWsj
* the Source Creation and Management node. Right-click the template and choose 0:Ow$
* Open. You can then make changes to the template in the Source Editor. gZI88Q
*/ aXAV`%b
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package com.tot.count; k?%?EsR
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/** n2NxO0
* ev}lb+pr)_
* @author /0PBY-O
*/ \>b
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public class CountBean { yHY \4OHS
private String countType; :T62_cFG
int countId; Ifghyh<d
/** Creates a new instance of CountData */ ~(( '1+
public CountBean() {} g%P6 f
public void setCountType(String countTypes){ ^W&qTSjh
this.countType=countTypes; q2o`.f+I
} lV4|(NQ9
public void setCountId(int countIds){ 'jr\F2
this.countId=countIds; &LRO^[d
} ^Jv$Wx
public String getCountType(){ ?C%mwW3pc
return countType; C,2k W`[V
} '<}N`PS#N
public int getCountId(){ &!|' EW
return countId; FaNr}$Pe
} pX5#!)
} 4CUzp.S`h
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CountCache.java gj(|#n5C
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/* L_TM]0D>7
* CountCache.java cym<uh-Wg^
* /I`AwCx
* Created on 2007年1月1日, 下午5:01 =;hz,+
* ,".1![b
* To change this template, choose Tools | Options and locate the template under }@Ap_xW
* the Source Creation and Management node. Right-click the template and choose 4=BIYC"Lu
* Open. You can then make changes to the template in the Source Editor. >(>,*zP<9
*/ fV b~j ;
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package com.tot.count; S!'Y:AeD&
import java.util.*; s7"NK"
/** Rm^3K
* v:$Ka@v6
* @author I&m C
*/ NNOemTh
public class CountCache { {`-f<>N3
public static LinkedList list=new LinkedList(); hH&A1vUv
/** Creates a new instance of CountCache */ }Kt`du=
public CountCache() {} thT2U8%T
public static void add(CountBean cb){ Mj9Mv<io
if(cb!=null){
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list.add(cb); <$"
} HLlp+;CF><
} y.iA]Ikz
} I34|<3t$
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CountControl.java S.4gfY
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/* ^k*h
* CountThread.java -o+<m4he
* 4p}?QR>tZ
* Created on 2007年1月1日, 下午4:57 K:<j=j@51
* 0~/'c0Ho
* To change this template, choose Tools | Options and locate the template under }0y2k7^]
* the Source Creation and Management node. Right-click the template and choose jTeHI|b
* Open. You can then make changes to the template in the Source Editor. Oq`CK f
*/ I_dO*k%l
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package com.tot.count; MWl2;qi
import tot.db.DBUtils; ij=_h_nA
import java.sql.*; ;4MC/Q/
/** tgR4C#a
* |E}-j;(
* @author
;4:[kv@
*/ uht>@ WSg|
public class CountControl{ TJO?BX_9
private static long lastExecuteTime=0;//上次更新时间 l_2B
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 j;7:aM"BQW
/** Creates a new instance of CountThread */ -/g<A~+i]$
public CountControl() {} d,5,OJY2f
public synchronized void executeUpdate(){ at
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Connection conn=null; X21k7 Ls
PreparedStatement ps=null; O>KrTK-AV
try{ D;Bij=
conn = DBUtils.getConnection(); =$wQA
conn.setAutoCommit(false); \cr)O^&
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); >d9b"T
for(int i=0;i<CountCache.list.size();i++){ b_&KL_vo{|
CountBean cb=(CountBean)CountCache.list.getFirst(); S^ q%+Z
CountCache.list.removeFirst(); j=up7395
ps.setInt(1, cb.getCountId()); ,SF>$
.
ps.executeUpdate();⑴ "n, %Hh
//ps.addBatch();⑵ W6A-/;S\
} B>kVJK`X
//int [] counts = ps.executeBatch();⑶ `'vNHY
conn.commit(); HOr.(gL!
}catch(Exception e){ .3
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e.printStackTrace(); SR$?pJh D%
} finally{ d(_;@%p1X
try{ ]=%oBxWAP
if(ps!=null) { Y(<(!TJ-
ps.clearParameters(); ul&}'jBr
ps.close(); !q[r_wL
ps=null; ;uhpo
} GQ8A}gwH
}catch(SQLException e){} ] :.
DBUtils.closeConnection(conn); dsG:DS`q
} Maw$^Tz,
} 0PdX>h.t
public long getLast(){ PN"=P2e/ 6
return lastExecuteTime; 1]wo
} !<UdG+iV
public void run(){ ;[q>
long now = System.currentTimeMillis(); #GfM!<q<
if ((now - lastExecuteTime) > executeSep) { 89YG
`
//System.out.print("lastExecuteTime:"+lastExecuteTime); jV.9d@EC
//System.out.print(" now:"+now+"\n"); Ru~;awV?
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); TNF+yj-|X:
lastExecuteTime=now; hbSXa'
executeUpdate(); \GdsQAF"
} 6#;u6@+}yy
else{ 8=,?Bh".
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); J93@\b
} R/\ qDY,@
} G<FB:?|
} k0IztFyj:R
//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 vVFT0_
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类写好了,下面是在JSP中如下调用。 I~&*8)xM
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<% @^t1SPp
CountBean cb=new CountBean(); wqF_hs(O
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Is(ZVI
CountCache.add(cb); 'R
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out.print(CountCache.list.size()+"<br>"); | E\ u
CountControl c=new CountControl(); X_ (n
c.run(); |o#pd\
out.print(CountCache.list.size()+"<br>"); *@fVog r^
%>