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: f~& a-
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CountBean.java &TN2 HZ-bJ
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/* ryD%i"g<
* CountData.java ol!86rky
* yM$J52#d#
* Created on 2007年1月1日, 下午4:44 }*;EFR 6'
* (*^DN{5
* To change this template, choose Tools | Options and locate the template under dBEIMn@
* the Source Creation and Management node. Right-click the template and choose MB$a82bY
* Open. You can then make changes to the template in the Source Editor. '%4P;HO
*/ vgPUIxB@
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package com.tot.count; Vb6K:ZnF
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/** T`L}[?w
* vb =CFV#
* @author n`5WXpz4;
*/ 4KIWb~0Y
public class CountBean { Cyk s
private String countType; XSD%t8<LO
int countId; xe:' 8J6L
/** Creates a new instance of CountData */ FUTn
public CountBean() {} f'/ KMe%<
public void setCountType(String countTypes){ n
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this.countType=countTypes; (9.yOc4
} cK}Pf+r>
public void setCountId(int countIds){ ,7/
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this.countId=countIds; O8 RzUg&
} xEoip?O?7F
public String getCountType(){ r#h {$iW
return countType; >[K?fJ$+
} =:K@zlO:
public int getCountId(){ .P/xs4
return countId; +^Jwo)R'b
} qe?Ggz3p.
} mUwUs~PjA
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CountCache.java D$pj#
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/* #tz8{o?ebN
* CountCache.java H`|0-`q
* Cg6;I.K
* Created on 2007年1月1日, 下午5:01 E`E'<"{Yd
* : ^(nj7D
* To change this template, choose Tools | Options and locate the template under *FPg#a+
* the Source Creation and Management node. Right-click the template and choose I)[B9rbe
* Open. You can then make changes to the template in the Source Editor. gduxA/aT
*/ |HgfV@Han
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package com.tot.count; S:97B\u`
import java.util.*; ]Y5dl;xrM)
/** ;/A}}B]y
* u8uW9 <
* @author NhlJ3/J j
*/ 5ZsDgOeY
public class CountCache { Sr7@ buF
public static LinkedList list=new LinkedList(); ~= 9Vv
/** Creates a new instance of CountCache */ 02M7gBS
public CountCache() {} &t[|%c*D&
public static void add(CountBean cb){ &wGg6$
if(cb!=null){ rt;gC[3\
list.add(cb); vl~%o@*_
} )+B=z}:Nfz
} GMb!Q0I8
} NKh,z&
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CountControl.java `i4I!E
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/* .CmL7
5
* CountThread.java ?'LM7RE$X6
*
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* Created on 2007年1月1日, 下午4:57 S-,kI
* 7,su f }=
* To change this template, choose Tools | Options and locate the template under +3?`M<L0
* the Source Creation and Management node. Right-click the template and choose R#fy60
* Open. You can then make changes to the template in the Source Editor. ;y>'yq}
*/ Jk~UEqr+
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package com.tot.count; ]
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import tot.db.DBUtils; yy))Z0E5
import java.sql.*; (\uAAW"
/** 3GINv3_
* 7 s-`QdWX
* @author y[p6y[r*
*/ Bfn]-]>sD
public class CountControl{ e5qvyUJM
private static long lastExecuteTime=0;//上次更新时间 {jUvKB_x
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 'Aet{A=9
/** Creates a new instance of CountThread */ ,*w>z
public CountControl() {} Jmy)J!ib*
public synchronized void executeUpdate(){ C&oxi$J:p+
Connection conn=null; V%o#AfMI_
PreparedStatement ps=null; m`a>,%}P"
try{ r'PE5xqF
conn = DBUtils.getConnection(); {"}+V`O{
conn.setAutoCommit(false); z=%IcSx;
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); QS%,7'EG
for(int i=0;i<CountCache.list.size();i++){ wK ][qZ ]
CountBean cb=(CountBean)CountCache.list.getFirst(); e18T(g_i
CountCache.list.removeFirst(); W&LBh%"g
ps.setInt(1, cb.getCountId()); ZnQ27FcW
ps.executeUpdate();⑴ % IPyCEJD
//ps.addBatch();⑵ ~q5-9{ma
} 2}|vWKej{
//int [] counts = ps.executeBatch();⑶ (A|B@a!Y>
conn.commit(); X`tOO
}catch(Exception e){ i63?"
e.printStackTrace(); D~7%};D[
} finally{ ;\q<zO@x
try{ ew/KZE
if(ps!=null) { @u<0_r
t
ps.clearParameters(); l#|J
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ps.close(); 'H
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ps=null; (T4k~T`3
} JH-nvv
}catch(SQLException e){} krwf8!bI
DBUtils.closeConnection(conn); ?Ip$;s
} 0rGj|@+;
} -^y1iN'D
public long getLast(){ pO5v*oONz+
return lastExecuteTime; l`oT:
} 8[f8k3g
public void run(){ @ >
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long now = System.currentTimeMillis(); H2s*s[T
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if ((now - lastExecuteTime) > executeSep) { Kl!DKeF
//System.out.print("lastExecuteTime:"+lastExecuteTime); w# xncH:1
//System.out.print(" now:"+now+"\n"); X #H:&*[!
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); c-v*4b/d
lastExecuteTime=now; \}n !yYh(
executeUpdate(); {W]bU{%.
} v5P*<U Ax
else{ /1H9z`qV
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); rn[$x(G
} *C
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} JIB?dIN
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} qW+=g]x\
//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 77 *v-8c
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类写好了,下面是在JSP中如下调用。 (xjqB{U
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<% 4;",@}
CountBean cb=new CountBean(); /
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); `\nON
CountCache.add(cb); ?hP<@L6K
out.print(CountCache.list.size()+"<br>"); i#Ne'q;T
CountControl c=new CountControl(); 0@JilGk1u
c.run(); q+r `e
out.print(CountCache.list.size()+"<br>"); ~r{\WZ.
%>