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: =Vy`J)z9
b8LoIY*
CountBean.java hGd<<\
T^T[$26
/* {.Z}5K
* CountData.java z|asa*
* Q2zjZC*'%
* Created on 2007年1月1日, 下午4:44 '|S%aMLZ)
* vk*=4}:
* To change this template, choose Tools | Options and locate the template under *g y{]
* the Source Creation and Management node. Right-click the template and choose ;3\3q1oX
* Open. You can then make changes to the template in the Source Editor. :T]o)
*/ MS0Fl|YA
k$H%.l;E
package com.tot.count; yHHt(GM|o
0j30LXI_
/** 9AxCiT.
* #<e\QE'!
* @author w"OP8KA:^T
*/ ms!r ef4`+
public class CountBean { DA2}{
private String countType; mN!lo;m5
int countId; iXjo[Rz^C
/** Creates a new instance of CountData */ L]d-hs
public CountBean() {} t5'V6nv
public void setCountType(String countTypes){ Z^]|o<.<I
this.countType=countTypes; wY~&Q}U
} TF 'U
public void setCountId(int countIds){ UB 6mqjPK
this.countId=countIds; UW9?p}F
} s<9RKfm
public String getCountType(){ %^1cyk
return countType; Q$:![}[(
} X{we/'>
public int getCountId(){ U Z|HJ8_
return countId; U$
F{nZ1
} aX~%5mF
} NPd%M
;5tazBy&:C
CountCache.java M/):e$S
Tszp3,]f
/* 0pJ
":Q/2)
* CountCache.java )(tM/r4`c&
* %H]lGN)
* Created on 2007年1月1日, 下午5:01 (tCUlX2
* /v/C<]
* To change this template, choose Tools | Options and locate the template under wKi^C8Z2
* the Source Creation and Management node. Right-click the template and choose :=8t"rO=W
* Open. You can then make changes to the template in the Source Editor. }';D]c
*/ *P 3V
)13dn]o=2
package com.tot.count; ] )F7)
import java.util.*; B*~5)}1op
/** FL8g5I
* t=u
Qb=
* @author "Ae@lINn[y
*/ 59zENUYl
public class CountCache { jMbC Y07v
public static LinkedList list=new LinkedList(); Zum0J{l
h
/** Creates a new instance of CountCache */ Kh4$ wwn
public CountCache() {} n @?4b8"
public static void add(CountBean cb){ OKi\zS
if(cb!=null){ f m(e3]
list.add(cb); k51Eyy50(
} ?[&2o|
} 2-"0 ^n{
} 8ZCo c5
iSFuT7;%
CountControl.java w|CZ7|6
{
.*y
/* kN%MP6? J
* CountThread.java +uBLk0/)>
* 0<8XI>.3D
* Created on 2007年1月1日, 下午4:57 S.Z9$k%
* [!
'op0
* To change this template, choose Tools | Options and locate the template under [kqYfY?K
* the Source Creation and Management node. Right-click the template and choose F q!fWl
* Open. You can then make changes to the template in the Source Editor. dB+N\HBY
*/ 4J?t_)
aA'|Rg,
package com.tot.count; N`E-+9L)
import tot.db.DBUtils; ATy*^sc&"
import java.sql.*; `;YU.*
/** xil[#W]7Ge
* n39t}`WIl
* @author %lX%8Z$v
*/ V97,1`
public class CountControl{ Y=`
private static long lastExecuteTime=0;//上次更新时间 LGc&o]k
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 A/7X9ir
/** Creates a new instance of CountThread */ JT9N!CGZ
public CountControl() {} %L [&,a
public synchronized void executeUpdate(){ hoT/KWD,
Connection conn=null; x+]!m/
PreparedStatement ps=null; 4CQ"8k(S"
try{ LTJc,3\,
conn = DBUtils.getConnection(); DI`%zLDcY
conn.setAutoCommit(false); 6l$L~>
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); -k(CJ5H9
for(int i=0;i<CountCache.list.size();i++){ 6{,HiY
CountBean cb=(CountBean)CountCache.list.getFirst(); `MEYd U1
CountCache.list.removeFirst(); 15$4&=O
ps.setInt(1, cb.getCountId()); cEe?*\G
ps.executeUpdate();⑴ _/S?#
//ps.addBatch();⑵ v+e|o:o#
} Y%|@R3[Nk
//int [] counts = ps.executeBatch();⑶ =<@\,xN>C
conn.commit();
/%A;mlf{
}catch(Exception e){
@HBEt^!
e.printStackTrace(); &TG5rUUg
} finally{ /H:I 68~
try{ n,~;x@=5
if(ps!=null) { h;V,n
ps.clearParameters(); W$qd/'%
ps.close(); {B*W\[ns
ps=null; 0t#g}
} "4H8A=
}catch(SQLException e){} hh~n#7w~IR
DBUtils.closeConnection(conn); $6F)R|
} hF3&i=;.
} 4yaxl\2
public long getLast(){ 0)Rw|(Fpo]
return lastExecuteTime; #Fu>|2F|
} Px5t,5xT8
public void run(){ ^MD;"A<
long now = System.currentTimeMillis(); 2X-l{n;>
if ((now - lastExecuteTime) > executeSep) { )'Wb&A'
//System.out.print("lastExecuteTime:"+lastExecuteTime); E3a_8@ZB7
//System.out.print(" now:"+now+"\n"); 7@a 0$coP
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); i`)!X:j
lastExecuteTime=now; qQ7w&9r.M
executeUpdate(); u)Q;8$`
} yBLUNIr
else{ "0jJh^vk
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); iA!7E;o
} VohhQ
} IfDx@ ?OB
} jnuY{0(&
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 IGFGa@C
`-B+JQmen
类写好了,下面是在JSP中如下调用。 -Uo?WXP]B'
j1Yq5`ia
<% K#K\-TR|$
CountBean cb=new CountBean(); Oajv^H,Em
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ^_p%Yv
CountCache.add(cb); K8^kJSF\
out.print(CountCache.list.size()+"<br>"); &[?CTZ
CountControl c=new CountControl(); +rNkN:/L
c.run(); kvsA]tK.
out.print(CountCache.list.size()+"<br>"); <
/p8r
%>