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: 0kNe?Xi
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CountBean.java ~7lTqY\
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/* e-CNQnO~
* CountData.java X$7Oo^1;
* ,67"C2Y
* Created on 2007年1月1日, 下午4:44 A9\]3 LY
* 7SgweZ}"
* To change this template, choose Tools | Options and locate the template under W_[|X}lWP
* the Source Creation and Management node. Right-click the template and choose ibd$%;bX3
* Open. You can then make changes to the template in the Source Editor.
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*/ g.B%#bfg
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package com.tot.count; X q}Ucpj
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/** lZ|L2Yg3uB
* ||-nmOy
* @author NJ;"jQ-
*/ g$*/XSr(
public class CountBean { fm(mO%
private String countType; @4IW=V
int countId; g>2aIun_Q
/** Creates a new instance of CountData */ ==QWwPpA
public CountBean() {} hpbwZ
public void setCountType(String countTypes){ YCa@R!M*O
this.countType=countTypes; *4<4
} s?QVX~S"
public void setCountId(int countIds){ %
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this.countId=countIds; d]tv'|E13
} _iG2J&1'L
public String getCountType(){ tigT@!`$Y
return countType; =N YgGEFq.
} /y}"M
public int getCountId(){ T>}0) s
return countId; S~KS9E~\
} aq3~!T;W
} 3lo;^KX !
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CountCache.java X}ZlWJ
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/* :P3{Nxa
* CountCache.java +c^_^Z$_4o
* s|Z:}W?{
* Created on 2007年1月1日, 下午5:01 PG{i,xq_B{
* ?b||Cr
* To change this template, choose Tools | Options and locate the template under =43I1&_
* the Source Creation and Management node. Right-click the template and choose 0cHfxy3
* Open. You can then make changes to the template in the Source Editor. O^5UB~
*/ ze`1fO|%
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package com.tot.count; Zy^=fM
import java.util.*; DH
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/** ^>C11v
* I*EJHBsQ5
* @author Q,{^S,s<
*/ RFw(]o,9cR
public class CountCache { Z&_y0W=t
public static LinkedList list=new LinkedList(); 4&Byl85q
/** Creates a new instance of CountCache */ !c%
public CountCache() {} t/}L36@+
public static void add(CountBean cb){ 'It?wB W
if(cb!=null){ B[r<m J
list.add(cb); vxZg &SRK
} > 2#%$lX6
} n-DaX
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} R {HV]o|qk
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CountControl.java S}[l*7
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/* tQWWgLM
* CountThread.java v:E;^$6Vn
* Yu'a<5f
* Created on 2007年1月1日, 下午4:57 L>dkrr)e
* r'/\HWNP
* To change this template, choose Tools | Options and locate the template under Hkdf $$\
* the Source Creation and Management node. Right-click the template and choose dL-i)F
* Open. You can then make changes to the template in the Source Editor. 6^)rv-L~5y
*/ 5F2_xH$5
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package com.tot.count; W{
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import tot.db.DBUtils; @}Zd (o
import java.sql.*; %}P4kEY
/** H+ lX-,
* J!{Al
* @author ',7a E@PJ
*/ OF[?Z
public class CountControl{ *m9{V8Yi2
private static long lastExecuteTime=0;//上次更新时间 gV8"VZg2
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 hoenQ6N^:
/** Creates a new instance of CountThread */ XVt/qb%)r
public CountControl() {} e+. \pe\
public synchronized void executeUpdate(){ l4rMk^>>
Connection conn=null; ldGojnS
PreparedStatement ps=null; 4WC9US-k
try{ C-m*?))go
conn = DBUtils.getConnection(); `5q
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conn.setAutoCommit(false); yEq#Dr
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); *^]~RhjB
for(int i=0;i<CountCache.list.size();i++){ Tzzq#z&F
CountBean cb=(CountBean)CountCache.list.getFirst(); Ytao"R/
CountCache.list.removeFirst(); aBhV3Fd[B
ps.setInt(1, cb.getCountId()); !SO8O
ps.executeUpdate();⑴ b O=yi)
//ps.addBatch();⑵ +L0w;w T
} zvY+R\,in
//int [] counts = ps.executeBatch();⑶ MuwQZ]u
conn.commit(); b7HffO O
}catch(Exception e){ d H?
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e.printStackTrace(); .Pe9_ZH$W
} finally{ ZtK\HDdp
try{ Gh}yb-$N`&
if(ps!=null) { o:"anHs
ps.clearParameters(); 9xFO]Y"
ps.close(); Pao%pA.<
ps=null; $d/&k`
} WkP
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}catch(SQLException e){} N2ied^* 0
DBUtils.closeConnection(conn); =wG+Ao
} {^}0 G^
} <@G8ni
public long getLast(){ oFDz;6
return lastExecuteTime; S{#cD1>.
} e)H!uR
public void run(){ "B{ECM;
long now = System.currentTimeMillis(); fY,|o3#
if ((now - lastExecuteTime) > executeSep) { 3GH(wSv9\
//System.out.print("lastExecuteTime:"+lastExecuteTime); L?5f+@0.
//System.out.print(" now:"+now+"\n"); -r<#rITH"
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ?kTWpXx"=
lastExecuteTime=now; ?+0GfIV
executeUpdate(); !TKkec8$
} 4/e60jA
else{ g&Vcg`
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 8X$LC
} pZ(Fx&fy
} zR;X*q"T$4
} W_`A"WdT.
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 -nbMTY}
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类写好了,下面是在JSP中如下调用。 ({^9<Us
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<% 6KZf%)$
CountBean cb=new CountBean(); g(C|!}ex/
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 'heJ"k?
CountCache.add(cb); L';MP^
out.print(CountCache.list.size()+"<br>"); Bux [6O%
CountControl c=new CountControl(); ccFn.($p?,
c.run(); 7nU6k%_ %
out.print(CountCache.list.size()+"<br>"); R\|lt)h
%>