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: u3!aKXnv<
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CountBean.java 8\Y/?$on
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/* n@LR?
* CountData.java K^V*JH\G
* {HV$hU+_)Q
* Created on 2007年1月1日, 下午4:44 SZOcFmC?
* P!?Je/Tz]
* To change this template, choose Tools | Options and locate the template under 8S&Kf>D
* the Source Creation and Management node. Right-click the template and choose q!iMc
* Open. You can then make changes to the template in the Source Editor. L lP
*/ 8:Yha4<Bv7
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package com.tot.count; ^!]Hm&.a
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/** MC.,n$O}6
* $}d| ~q\
* @author Onr#p4UT
*/ Da)rzr|}>3
public class CountBean { Zk+J= Cwq}
private String countType; T-Od|T@[
int countId; { VC4rA
/** Creates a new instance of CountData */ s5 2c`+
public CountBean() {} x4SI TY
public void setCountType(String countTypes){ 1a#oJU
this.countType=countTypes; B,SH9,
} GW]E,a
public void setCountId(int countIds){ :kycIM]s
this.countId=countIds; 1'5I]D
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} <B]\&
public String getCountType(){ &Mset^o
return countType; N0be=IO5#
} zcrLd={
public int getCountId(){ {;(X#vK}9
return countId; LGN,8v<W(
} /Kmzi9j+
} (wmMHo|
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CountCache.java !GkwbHr+p
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/* L[zg2y
* CountCache.java eSZS`(#!(
* B;'Dh<J1
* Created on 2007年1月1日, 下午5:01 cH>rS\|Y
* :uZfdu
* To change this template, choose Tools | Options and locate the template under ; 6Wlu3I
* the Source Creation and Management node. Right-click the template and choose _m!TUT8o
* Open. You can then make changes to the template in the Source Editor. |irqv< r
*/ dw)SF,
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package com.tot.count; $|v_ pjUu]
import java.util.*; Lm<"W_
/** ||y5XXs
* 9X8{"J
* @author )u7*YlU\I
*/ Wxl^f?I`:
public class CountCache { OE(H:^ZR
public static LinkedList list=new LinkedList(); o5 6_t{<
/** Creates a new instance of CountCache */ Dc |!H{Yr
public CountCache() {} ]KGLJ~hm>
public static void add(CountBean cb){ _W 41;OY
if(cb!=null){ bS{7 *S
list.add(cb); ![WX -"lW
} kBY54pl
} zdCeOZ 6
} _8C0z=hz
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CountControl.java V\zf yH\~
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/* OYGh!sW
* CountThread.java (yFR;5Fo
* @R=gJ:&a
* Created on 2007年1月1日, 下午4:57 hd~X c
* v\*43RL
* To change this template, choose Tools | Options and locate the template under jsSxjf;O
* the Source Creation and Management node. Right-click the template and choose .3Nd[+[
* Open. You can then make changes to the template in the Source Editor. )rv5QH`i
*/ 7<[p1C*B
o+W5xHe^1
package com.tot.count; ]=p@1
import tot.db.DBUtils; 16MRLDhnD
import java.sql.*; *loPwV8
/** G#/}_P
* $ WA Fr
* @author 8P r H"pI
*/ @NGK2J
public class CountControl{ >W"gr]R<
private static long lastExecuteTime=0;//上次更新时间 (#* 7LdZ
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 d%?+q0j
/** Creates a new instance of CountThread */ W=M`Bkw{
public CountControl() {} <}b`2/wP
public synchronized void executeUpdate(){ %sb)U~gP
Connection conn=null; ZdHfZ3)dB
PreparedStatement ps=null; _[-+%RP
try{ IM&2SSmYNH
conn = DBUtils.getConnection(); &Zl$7
conn.setAutoCommit(false); $: "r$7
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); SU;PmG4
for(int i=0;i<CountCache.list.size();i++){ <v;;:RB6c
CountBean cb=(CountBean)CountCache.list.getFirst(); I*R[8|
CountCache.list.removeFirst(); *6~ODiB
ps.setInt(1, cb.getCountId()); F)/}Q[o8
ps.executeUpdate();⑴ JqTkNKi/s
//ps.addBatch();⑵ c6sGjZdR
}
#|fa/kb~
//int [] counts = ps.executeBatch();⑶ vCT5do"C&
conn.commit(); fk)ts,p?
}catch(Exception e){ tS,nO:+x
e.printStackTrace(); |du@iA]dP
} finally{ e2Sm.H '
try{ LtKiJ.j?A
if(ps!=null) { t3K7W2bz
ps.clearParameters(); D.o|pTZ
ps.close(); }f np}L
ps=null; ([zt}uf
} DGr{x}Kq
}catch(SQLException e){} 6\ /x
DBUtils.closeConnection(conn); J@Eqqyf"
} 98h,VuKVaB
} KE:PRX
public long getLast(){ T1hr5V<U
return lastExecuteTime; /*g3TbUs
} WyVFhAuU
public void run(){ zu&5[XL
long now = System.currentTimeMillis(); $8o(_8Q)
if ((now - lastExecuteTime) > executeSep) { \|nF55W [
//System.out.print("lastExecuteTime:"+lastExecuteTime); 1"3|6&=
//System.out.print(" now:"+now+"\n"); ^RytBwzKM
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); . $uvQpyh
lastExecuteTime=now; GwxxW
executeUpdate(); |cStN[97%
} #}L75
else{ `E>HpRcxD
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); L<!}!v5ja
} :#58m0YLA:
} V{;! vt~
} Xu`c_
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 Mit,X
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类写好了,下面是在JSP中如下调用。 pDb5t>
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<% B
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CountBean cb=new CountBean(); W-q2|NK
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); G$pTTT6#
CountCache.add(cb); w*<XPBi
out.print(CountCache.list.size()+"<br>"); NR-d|`P;
CountControl c=new CountControl(); ?>5[~rMn
c.run(); GqumH/;
out.print(CountCache.list.size()+"<br>"); i`/_^Fndyu
%>