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: )-jA4!&
@la/sd4`
CountBean.java nr*nX
&|]GTN`E
/* ^$>Q6.x?*)
* CountData.java =qWcw7!"
* Jam&Rj,
* Created on 2007年1月1日, 下午4:44 .<fn+]
* Fy6(N{hql
* To change this template, choose Tools | Options and locate the template under $V/Hr/0
* the Source Creation and Management node. Right-click the template and choose Xh5&J9pw
* Open. You can then make changes to the template in the Source Editor. ;#)vw;XR
*/ t ZL|;K
JKjVrx>
@
package com.tot.count; GZq~Pl
uge~*S
/** kq$0~lNI$
* fK
4,k:YC
* @author c'!+]'Lr
*/ 6&,{"N0T
public class CountBean { $wm.,Vb
private String countType; f,(@K%
int countId; S%Bm4jY
/** Creates a new instance of CountData */ {SRv=g
public CountBean() {} =".sCV9"N
public void setCountType(String countTypes){ LlF|VR&P.
this.countType=countTypes; )x<oRHx]
} 'pa8h L
public void setCountId(int countIds){ dq4t@:\o0
this.countId=countIds; }i F|NIV
} N5F+h94z]
public String getCountType(){ )b=m|A GX
return countType; T/Bx3VWL
} S-7ryHH*0
public int getCountId(){ qmF+@R&^i
return countId; 9O{b8=\}
} !h.bD/?K
} u-k!h
y,F|L?dIq
CountCache.java +\GuZ5`
6DxT(VU}
/* TjWMdoU$J
* CountCache.java rx\f:-3g
* b/g~;| <
* Created on 2007年1月1日, 下午5:01 !#TM%w
* UNhM:!A
* To change this template, choose Tools | Options and locate the template under XJguw/[wm
* the Source Creation and Management node. Right-click the template and choose +9NI=s6
* Open. You can then make changes to the template in the Source Editor. 0N`'a?x
*/ ApotRr$)
o#frNT}
package com.tot.count; FV>xAU$
import java.util.*; KKGwMJku}
/** _n12Wx{
* PESJ7/^E
* @author ]D\p<4uepM
*/ ;Ebpf J
public class CountCache { c]3^2Ag,
public static LinkedList list=new LinkedList(); g6!#n
/** Creates a new instance of CountCache */ +l@+e_>
public CountCache() {} 40Z/;,wp{
public static void add(CountBean cb){ Mb\[` 4z
if(cb!=null){ Jo9!:2?
list.add(cb); mP+rPDGp
} 7p+uHm
} tbq_Rg7s
} !k0t
(.
V1>>]]PS
CountControl.java nk+*M9r|I
I.L8A|nZ
/* bl-t>aO*.V
* CountThread.java ]qNPOnlp
* r/BiR0$E
* Created on 2007年1月1日, 下午4:57 7).zed^
* Jm{~H%
* To change this template, choose Tools | Options and locate the template under Tx0l^(n
* the Source Creation and Management node. Right-click the template and choose liG3
* Open. You can then make changes to the template in the Source Editor. !e(ZEV g
*/ -Drm4sTpDb
G##^xFx
package com.tot.count; j,CMcP7A -
import tot.db.DBUtils; D[iIj_CKQ
import java.sql.*; H=k`7YN
/** (!&g (l;
* KqT~MPl
* @author S&m5]h!D
*/ D$[/|%3
public class CountControl{ R@H}n3,
private static long lastExecuteTime=0;//上次更新时间 iWNTI
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Ch9A6?=Hj8
/** Creates a new instance of CountThread */ DUK.-|a7
public CountControl() {} ofA6EmQ37
public synchronized void executeUpdate(){ .1C|J
Connection conn=null; e{x|d?)8
PreparedStatement ps=null; 5 cE!'3Y
try{ K\GIh8L
conn = DBUtils.getConnection(); lt&30nf=
conn.setAutoCommit(false); \w=7L-
8
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); TAu*lL(F
for(int i=0;i<CountCache.list.size();i++){ =7Y gES
CountBean cb=(CountBean)CountCache.list.getFirst(); tFd^5A*
CountCache.list.removeFirst(); T6ZJ SKM
ps.setInt(1, cb.getCountId()); Y;eJo
ps.executeUpdate();⑴ Eh)VU_D
//ps.addBatch();⑵ fJ3qL#'
} w5(GRAH
//int [] counts = ps.executeBatch();⑶ m 5NF)eL
conn.commit(); J}.y+b>8\
}catch(Exception e){ kty,hAXe
e.printStackTrace(); IK6XJsz$J
} finally{ h;KI2k_^
try{ uhLg2G^h
if(ps!=null) {
ka&-tGg
ps.clearParameters(); C"IP1N
ps.close(); EN%Xs578
ps=null; Eu
)7@
} qpl "j-
}catch(SQLException e){} H\3CvFm
DBUtils.closeConnection(conn); lC1X9Op
} vN7ihe[C
} ~5wCehSb
public long getLast(){ -7">A~c
return lastExecuteTime; [21tT/
} }#
-N7=h
public void run(){ 'eo2a&S2D
long now = System.currentTimeMillis(); j86s[Dty
if ((now - lastExecuteTime) > executeSep) { T"Q4vk,3*J
//System.out.print("lastExecuteTime:"+lastExecuteTime); PSHs<Z47
//System.out.print(" now:"+now+"\n"); %p2 C5z?
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Vb 4Qt#o
lastExecuteTime=now; ,h]N*Z-I"
executeUpdate(); (U`7[F
} nwN<Q\]S
else{ ORx,n7-
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); (7ew&u\Li
} r+0)l:{.
} oT|E\wj
} =WEfo;
//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 i%*x7zjY{
SsznV}{^
类写好了,下面是在JSP中如下调用。 H[,.nH_>+
O:7y-r0i
<% G)4 3Y!
CountBean cb=new CountBean(); Y+?bo9CES!
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); GN1cnM>`
CountCache.add(cb); #zy,x
out.print(CountCache.list.size()+"<br>"); xJ&StN/'
CountControl c=new CountControl(); ?$n<