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: \-RVPa8k
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CountBean.java FWuk@t[<O
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/* qh/}/Sl;
* CountData.java v9l|MI15V
* +t<'{KZ7;
* Created on 2007年1月1日, 下午4:44 Hb@PQcj
* UYsyVY`Fm|
* To change this template, choose Tools | Options and locate the template under R;F z"J
* the Source Creation and Management node. Right-click the template and choose )r6d3-p1
* Open. You can then make changes to the template in the Source Editor. H1a<&7
*/ P: )YKro]
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package com.tot.count; P{o //M
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/** K5:>
* .u&GbM%Ga
* @author IGcYPL\&
*/ Un{ 9reX5
public class CountBean { LABLT;c
private String countType; yn KgNi
int countId; 9vJ'9Z2\
/** Creates a new instance of CountData */ ]B9Ut&mF;
public CountBean() {} #mH4\s
public void setCountType(String countTypes){ Oh/2$72
this.countType=countTypes; F@jyTIS^
} Oo8"s+G
public void setCountId(int countIds){ d(;Qe}ok>
this.countId=countIds; Wf5ohXm>
} m7NrS?7
public String getCountType(){ p^?]xD(
return countType; jt4c*0z
} uI+^8-HZ;
public int getCountId(){ IjnO2X
return countId; (xlAS
}
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} QOKE9R#Y
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CountCache.java av4g/7=
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/* |-.r9;-b
* CountCache.java E:S (v
* rd!4u14
* Created on 2007年1月1日, 下午5:01 g;t>jgX
* l|'{Cb
* To change this template, choose Tools | Options and locate the template under 0v'FE35~s
* the Source Creation and Management node. Right-click the template and choose |(O _K(
* Open. You can then make changes to the template in the Source Editor. ul[+vpH9
*/ tU, >EbwO
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package com.tot.count; pTIE.:g(
import java.util.*; 7&{[Y^R]"
/** $C~OV@I
* x/xd
* @author 9ZXEy }q57
*/ 3ew`e"s
public class CountCache { H?W8_XiN
public static LinkedList list=new LinkedList(); hF7#i_UN<
/** Creates a new instance of CountCache */ 4/ M~#
public CountCache() {} _S;Fs|p_
public static void add(CountBean cb){ <R@w0b>
if(cb!=null){
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list.add(cb); j5]6CG_
} l[Rl:k!
} 0ntf%#2{
} Qlgii_?#@
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CountControl.java fKjUEMRK
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/* :;u?TFCRx
* CountThread.java Y> f 6
* C6cEt5
* Created on 2007年1月1日, 下午4:57 BaUcmF2Q
* B|(M xR6m
* To change this template, choose Tools | Options and locate the template under cR"?EQ] `N
* the Source Creation and Management node. Right-click the template and choose wSd o7Lb
* Open. You can then make changes to the template in the Source Editor. #JIh-h@
*/ Fi_JF;
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package com.tot.count; IW-lC{hK
import tot.db.DBUtils; (_'Efpg|
import java.sql.*; si.w1
/** #gd`X|<Ch
* KG8Km
* @author >)p8^jX
*/ P<{N)H 2r
public class CountControl{ pQf5s7
private static long lastExecuteTime=0;//上次更新时间 d1=fA%pJ
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 WwBs_OMc
/** Creates a new instance of CountThread */ v6q oH)n
public CountControl() {} z6f N)kw
public synchronized void executeUpdate(){ szW85{<+
Connection conn=null; K|g+Wt^tQ
PreparedStatement ps=null; fkmN?CU{1%
try{ 5$.e5y<&(
conn = DBUtils.getConnection(); i$:QOMA
conn.setAutoCommit(false); M
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); "de3Sbj@?
for(int i=0;i<CountCache.list.size();i++){ ofIw7D*h
CountBean cb=(CountBean)CountCache.list.getFirst(); wtpz ef=
CountCache.list.removeFirst(); jizp\%W+
ps.setInt(1, cb.getCountId()); B+8B<xZ
ps.executeUpdate();⑴ >p|tIST
//ps.addBatch();⑵ mcFJ__3MAV
} %
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//int [] counts = ps.executeBatch();⑶ /3ty*LQT
conn.commit(); B6gn(w3
}catch(Exception e){ pwG" _|h
e.printStackTrace(); d2XSw>
} finally{ ,U^V]jC
try{ 2J5RZg9jL
if(ps!=null) { m0zbG1OE
ps.clearParameters(); `rLy7\@;
ps.close(); -U#e
ps=null; N(@B3%H2/J
} MX\v2["FoV
}catch(SQLException e){} zv}3Sl@
DBUtils.closeConnection(conn); 3}lT"K
} :kz"Wya.
} y2:~_MD
public long getLast(){ "{F e
return lastExecuteTime; a8wQ,
} m^M sp:T,
public void run(){ OX!<{9o
long now = System.currentTimeMillis(); vv%
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if ((now - lastExecuteTime) > executeSep) { c^ifHCt|
//System.out.print("lastExecuteTime:"+lastExecuteTime); 9yt)9f
//System.out.print(" now:"+now+"\n"); PBo;lg`
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); G&2`c\u{
lastExecuteTime=now; ;H;c Sn5uL
executeUpdate(); o,yP9~8\
} 1o*eu&@
else{ h~R= ?%H[
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); pX~X{JTaL)
} M~jV"OF=
} S%t*!
} *[SOz)
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 PUJkC
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类写好了,下面是在JSP中如下调用。 { *&Wc Os
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<% 5U!yc7eBI/
CountBean cb=new CountBean(); n?=d)[]
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); B{ptP4As-
CountCache.add(cb); }cPH}[$zF
out.print(CountCache.list.size()+"<br>"); ljw(cUM
CountControl c=new CountControl(); N&]GPl0
c.run(); 6b6rM%B.oD
out.print(CountCache.list.size()+"<br>"); EFqYEDXW
%>