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: Z
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CountBean.java dI!/H&`B]
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/* {:Kr't<XzF
* CountData.java (S?DKPnR
* B^ddi
* Created on 2007年1月1日, 下午4:44 1Lp; LY"_
* f=S2O_Ee
* To change this template, choose Tools | Options and locate the template under {.y_{yWo
* the Source Creation and Management node. Right-click the template and choose M9Nr/jE
* Open. You can then make changes to the template in the Source Editor. q1ZZ T"'
*/ 8yH)9#>
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package com.tot.count; <~:2~r
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/** ~CdW:t
* G!h75G20
* @author <z>oY2%
*/ 'G>9 iw
public class CountBean { ooC9a>X
private String countType; TNK1E
int countId; 1xh7KBr,
/** Creates a new instance of CountData */ k_Y7<z0G
public CountBean() {} W,_2JqQp
public void setCountType(String countTypes){ sH >zsc
this.countType=countTypes; ;P/ 4.|<
} %&q}5Y4!
public void setCountId(int countIds){ Bvh{|tP4
this.countId=countIds; XP?)xDr8
} a#& ( i
public String getCountType(){ :F@goiuC
return countType; *v?kp>O
} y*v|q=
public int getCountId(){ l"jYY3N|h
return countId; LhM$!o?W
} Nd{U|k3pL
} 7q5*grm
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CountCache.java %/5Wj_|p
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/* KC9e{
* CountCache.java ,CuWQ'H
* i"
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* Created on 2007年1月1日, 下午5:01 p(8 @
* XrWWV2[
* To change this template, choose Tools | Options and locate the template under .`V$j.a
* the Source Creation and Management node. Right-click the template and choose `u PLyS.
* Open. You can then make changes to the template in the Source Editor. a/1;|1a.
*/
*
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package com.tot.count; K}^#VlY9
import java.util.*; a7453s
/** r\Yh'cRW{
* Id>4fF:o
* @author sowwXrECg@
*/ P=\{
public class CountCache { F*r)
public static LinkedList list=new LinkedList(); g.vE%zKL
/** Creates a new instance of CountCache */ tMp!MQ
public CountCache() {} $(]nl%<Q
public static void add(CountBean cb){ <JU3sXl
if(cb!=null){ 7]ysvSM
list.add(cb); DuZ Zu
} GQ>0E
} di0@E<@1:
} 8&|
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CountControl.java fwV2b<[
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/* f.+1Ubq!5
* CountThread.java #jW=K&;
* \=bKuP(it
* Created on 2007年1月1日, 下午4:57 nPqpat`E
* 6$'*MpYF4
* To change this template, choose Tools | Options and locate the template under k0K$OX*:e
* the Source Creation and Management node. Right-click the template and choose $?bD55
* Open. You can then make changes to the template in the Source Editor. !2l2;?jM
*/ V
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package com.tot.count; %Uz\P|6PO
import tot.db.DBUtils; ZDgT"53
import java.sql.*; vZ"gCf3#?3
/** FiUwy/,ZV
* "wTCO1
* @author {7z]+ h
*/ |%v:>XEO
public class CountControl{ /Xb4'Qj
private static long lastExecuteTime=0;//上次更新时间 ^MF 2Q+
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 1BZ##xV*:G
/** Creates a new instance of CountThread */ s(3HZ>qx;
public CountControl() {} 80[# 6`
public synchronized void executeUpdate(){ x5BS|3W$a
Connection conn=null; J
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PreparedStatement ps=null; -bzlp7q*
try{ 1BU97!
conn = DBUtils.getConnection(); jS##zC
conn.setAutoCommit(false); UGy3B)
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 9n{Y6I
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for(int i=0;i<CountCache.list.size();i++){ Hy&Z0W'l
CountBean cb=(CountBean)CountCache.list.getFirst(); ]h(Iun
CountCache.list.removeFirst(); Babzrt-
ps.setInt(1, cb.getCountId()); $S|+U}]C
ps.executeUpdate();⑴ a'?;;ZC-
//ps.addBatch();⑵ 8X"4RyNSn
} zdRVAcrwQ
//int [] counts = ps.executeBatch();⑶ rSJ!vQo
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conn.commit(); dR1IndZl
}catch(Exception e){ xw
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e.printStackTrace(); $jE<n/8
} finally{ H/x0'
try{ A+* lV*@0
if(ps!=null) { ZZI}
Ot{
ps.clearParameters(); Jcze.t
ps.close(); K6p\ >J
ps=null; O0L]xr
} Qr$
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}catch(SQLException e){} RdWn =;
DBUtils.closeConnection(conn); %"A8Af**I
} G&{yM2:E
} N{HAWB{
public long getLast(){ c-XO}\?
return lastExecuteTime; Xpg-rxX
} ?j.a>{
public void run(){ -EP1Rl`\
long now = System.currentTimeMillis(); 92<+ug =
if ((now - lastExecuteTime) > executeSep) { `+n#CWZ"Y
//System.out.print("lastExecuteTime:"+lastExecuteTime); <1*.:CL"s
//System.out.print(" now:"+now+"\n"); 20|_wAA5
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ~
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lastExecuteTime=now; e72Fz#<q
executeUpdate(); >ceC8"}J5M
} }={@_g#
else{ KqntOo}
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); M> WWP3
} -^m?%_<50l
} !?JZ^/u
} qr%N/7
//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 MSS[-}
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类写好了,下面是在JSP中如下调用。 u'l4=e
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<% lz#.f,h
CountBean cb=new CountBean(); qSr]d`7@
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); :k1?I'q%
CountCache.add(cb); GuR^L@+ -.
out.print(CountCache.list.size()+"<br>"); &SbdX
CountControl c=new CountControl(); _`?cBu`
c.run(); #17 &rizl
out.print(CountCache.list.size()+"<br>"); .>R`#@+I
%>