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: <(_${zR
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CountBean.java jwO7r0?\`G
#B@*-
/* * TByAa{
* CountData.java :LLz$[c8
* s)}EMDY
* Created on 2007年1月1日, 下午4:44 5"z~BE7
* j$Vtd&
* To change this template, choose Tools | Options and locate the template under >K*TgG6!X
* the Source Creation and Management node. Right-click the template and choose rnQ9uNAu
* Open. You can then make changes to the template in the Source Editor. o?><(A|
*/ )F m'i&F_
} QpyU%
package com.tot.count; 3Gt@Fo=
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/** rq|>z .
* no9=K4h`
* @author %h}3}p#4
*/ 'Ooq.jaK;/
public class CountBean { #K\;)z(?
private String countType; \
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int countId; ~' q&rvk`
/** Creates a new instance of CountData */ 15ImwQ
public CountBean() {} (``|5;T\
public void setCountType(String countTypes){ 3yu,qb'"&
this.countType=countTypes; `3L?x8g
} Qk8YR5K
public void setCountId(int countIds){ 8_{XrTw(
this.countId=countIds; {jo"@&2S
} HiEQs|""'
public String getCountType(){ ni-4~k
return countType; ew1bb K>
} &?M'(` ~
public int getCountId(){ =' &TqiIv"
return countId; l-M
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} <^"0A
} r-ljT<f%J[
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CountCache.java ^K[[:7Aem
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/* PY[!H<tt
* CountCache.java Vc&xXtm[v
* D`NQEt"(
* Created on 2007年1月1日, 下午5:01 dwz{Yw(
* crU]P $a
* To change this template, choose Tools | Options and locate the template under :JCe,1!3@
* the Source Creation and Management node. Right-click the template and choose ]lA.?
* Open. You can then make changes to the template in the Source Editor. 6B@{X^6y
*/ Jqqt@5Ni
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package com.tot.count; +A<7:`sO
import java.util.*; p"QV| `
/** '/@i}
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* `W{y
* @author M~-jPY,+
*/ M(.Up
public class CountCache { C[nacAi
public static LinkedList list=new LinkedList(); T9]:,
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/** Creates a new instance of CountCache */ jo ~p#l.'
public CountCache() {} A~#w gLGn
public static void add(CountBean cb){ -}P/<cu:
if(cb!=null){ dgW/5g
list.add(cb); kx07Ium
} #RP7?yGM,
} Df0m
} i~.9B7hdE
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CountControl.java =QW:},sp
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/* leO..M
* CountThread.java ef]60OtP
* .h\[7r
* Created on 2007年1月1日, 下午4:57 d5 U+]g
* ?o_D#gG*
* To change this template, choose Tools | Options and locate the template under ,{sCI/
* the Source Creation and Management node. Right-click the template and choose *+>QKR7
* Open. You can then make changes to the template in the Source Editor. ePe/@g1K*
*/ "U
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package com.tot.count; Fes/8*-
import tot.db.DBUtils; HsAKz]Mq
import java.sql.*; E(0 [/N~
/** j/w*2+&v
* Q#sLIZ8=
* @author laGIu0s{
*/ xkmqf7w
public class CountControl{ !KmSLr7xU
private static long lastExecuteTime=0;//上次更新时间 g:fzf>oQ>p
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 H(ds
/** Creates a new instance of CountThread */ =l1O9/\9
public CountControl() {} O"f|gc)GLz
public synchronized void executeUpdate(){ _2nNCu (
Connection conn=null; mY!&*nYn|
PreparedStatement ps=null; n]snD1?KX
try{ 8?&!@3n
conn = DBUtils.getConnection(); h}f l:J1C
conn.setAutoCommit(false); ZqJyuTPv
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); {{Z3M>Q
for(int i=0;i<CountCache.list.size();i++){ dS~#Lzm
CountBean cb=(CountBean)CountCache.list.getFirst(); qb>mUS
CountCache.list.removeFirst(); V.~C.x
ps.setInt(1, cb.getCountId()); j$}W%ibj
ps.executeUpdate();⑴ 75RQ\_zDu
//ps.addBatch();⑵ Hy#<fKz`!
} P> ilRb
//int [] counts = ps.executeBatch();⑶ m>LC2S;
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conn.commit(); `Y.Q{5Y
}catch(Exception e){ ~"i4"Op&
e.printStackTrace(); cA25FD
} finally{ 4
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try{ F;<cG`|Rx
if(ps!=null) { 4%,E;fB?=
ps.clearParameters(); ~+bS D<!b
ps.close(); FdMxw*}
ps=null; )L%[(iI,x
} 1bpjj'2%x
}catch(SQLException e){} Ah1fcXED
DBUtils.closeConnection(conn); i")ucrf
} 3NxwQ,~
} h-=lZ~W~
public long getLast(){ t.= 1<Ed
return lastExecuteTime; 9e'9$-z
} J?84WS
public void run(){ `HJRXoLySW
long now = System.currentTimeMillis(); 9zD^4j7
if ((now - lastExecuteTime) > executeSep) { 6YpP/
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//System.out.print("lastExecuteTime:"+lastExecuteTime); 7W `gN[*
//System.out.print(" now:"+now+"\n"); .lIkJQ3d
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); q5u"v
lastExecuteTime=now; ahqsbNu1
executeUpdate(); @#KZ2^
} %Astfn(U{4
else{ [+z*&~'
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); XonI
} B3-;]6
} DXc3u^
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} dMjAG7U
//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 qo62!q
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类写好了,下面是在JSP中如下调用。 E6mwvrm8
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<% 8@-
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CountBean cb=new CountBean(); 'n0u6hCSb
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ,pMH`
CountCache.add(cb); Cz]NSG 5
out.print(CountCache.list.size()+"<br>"); )%=oJ!)
CountControl c=new CountControl(); Q
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c.run(); 4l`"P~=2<
out.print(CountCache.list.size()+"<br>"); :;u?TFCRx
%>