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: J/*[wj
+%~g$#tlJo
CountBean.java t-Fl"@s
wIiT
:o
/* V)Xcn'h
* CountData.java pV+;/y_
* Kj>_XaFCg!
* Created on 2007年1月1日, 下午4:44 8ksDXf`.
* d16PY_
* To change this template, choose Tools | Options and locate the template under \ d;Ow8%d/
* the Source Creation and Management node. Right-click the template and choose ixkg,
* Open. You can then make changes to the template in the Source Editor. )G|UB8]
*/ MLb\:Ihy
G j:|
package com.tot.count; u@3w$"Pv1
ZtT`_G&
/** pL-$Np] V
* ={oO9.9
* @author hv)($;
*/ *\>2DUu\`
public class CountBean { ,5*4%*n\
private String countType; #75;%a8
int countId; \#}%E h
b
/** Creates a new instance of CountData */ ),Rj@52l
public CountBean() {} *dl@)~i
public void setCountType(String countTypes){ ,O+7nByi[V
this.countType=countTypes; 1$W!<:uh
} ~}11 6K
public void setCountId(int countIds){ M/qiA.C@W
this.countId=countIds; N@>S>U8C
} EIfrZg7R
public String getCountType(){ IR&u55#I6
return countType; PTh
Ya
} s5dh]vNN
public int getCountId(){ ^eRuj)$5A
return countId; WveFB%@`;
} -wt2ydzos
} b,W'0gl
wtKh8^:YD
CountCache.java ublY!Af
YGO@X(ej,
/* A.FI] K@
* CountCache.java o5R\7}]GE
* m~K]|]iqQ
* Created on 2007年1月1日, 下午5:01 zl[JnVF\6
* CAA~VEUL
* To change this template, choose Tools | Options and locate the template under #@fypCc
* the Source Creation and Management node. Right-click the template and choose 1d"P) 3dQ
* Open. You can then make changes to the template in the Source Editor. Y4O L 82Y
*/ jj2UUQ|
9lxT5Wg
package com.tot.count; .%A2
import java.util.*; #rwR)9iC0
/** SJ-Sac58r
* ]lY9[~
v
* @author `<n:D`{dZ
*/ `dZ|}4[1
public class CountCache { %r"GL
public static LinkedList list=new LinkedList(); NC}#P<U
/** Creates a new instance of CountCache */ u|c+w)a
public CountCache() {} -Me\nu8(RF
public static void add(CountBean cb){ ;=OH=+Rl
if(cb!=null){ 5PPpX =\
list.add(cb); oX~CTunP
} v2'JL(=
} &?nF';&
} "q.uiz+1:
di5_5_$`o
CountControl.java %U7B0-
hz%IxI9
/* ap~Iz
* CountThread.java
_1'Pb/1
* ;GSJnV
* Created on 2007年1月1日, 下午4:57 *&]l
* \t@`]QzG:
* To change this template, choose Tools | Options and locate the template under UJ[a&b
* the Source Creation and Management node. Right-click the template and choose $EIkk= z
* Open. You can then make changes to the template in the Source Editor. i`$rzXcS
*/ /(aX>_7jg
fna>>
package com.tot.count; gOM`I+CwT
import tot.db.DBUtils; pS;dvZ
import java.sql.*; ise}> A!t
/** ,0bM*qob
* z
sPuLn9G
* @author )|x5#b-lz
*/
lijy?:__
public class CountControl{ rYQ@"o0/Y
private static long lastExecuteTime=0;//上次更新时间 CdO-xL6F
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 : 4WbDeR
/** Creates a new instance of CountThread */ l0{DnQA>I
public CountControl() {} P}`1#$
public synchronized void executeUpdate(){ iurB8~Y
Connection conn=null; }i:'f2/
PreparedStatement ps=null; 0)!zhO_}
try{ ,be?GAq
conn = DBUtils.getConnection(); m5N&7qgp
conn.setAutoCommit(false); (xed(uFEK
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); +.I'U9QeUN
for(int i=0;i<CountCache.list.size();i++){ _4$DnQ6&
CountBean cb=(CountBean)CountCache.list.getFirst(); (?y2@I}
CountCache.list.removeFirst(); 6,1|y%(f
ps.setInt(1, cb.getCountId()); 5QJL0fc
ps.executeUpdate();⑴ /p0LtUMu
//ps.addBatch();⑵ us%RQ8=k
} zQ}N
mlk
//int [] counts = ps.executeBatch();⑶ !++62Lf
conn.commit(); 8zWPb
}catch(Exception e){ FOi`TZ8
e.printStackTrace(); ~*[4DQ[\
} finally{ S45>f(!
try{ C:MGi7f
if(ps!=null) { h+D=/:B
ps.clearParameters(); YWrY{6M
ps.close(); Cl!jK^AbG
ps=null; {1|7N
GQ
} ZF(=^.gc
}catch(SQLException e){} {C6;$#7P
DBUtils.closeConnection(conn); UE w3AO
} l$_rA~Mo
} z&,sm5Lb
public long getLast(){ T
l(uqY?9
return lastExecuteTime; \r,.hUp
} $:II@=
public void run(){ M) XQi/
long now = System.currentTimeMillis(); m?$G(E5
if ((now - lastExecuteTime) > executeSep) { PSS/JFZ^
//System.out.print("lastExecuteTime:"+lastExecuteTime); !p2,|6Y`y
//System.out.print(" now:"+now+"\n"); D(U3zXdO
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); @(fY4]K
lastExecuteTime=now; ilpZ/Rs
executeUpdate(); agT[y/gb
} e~]e9-L>I
else{ "IJMvTmj
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); MWh+h7k'
} qXhf?x
} l>Ja[`X@
} y4rJ-
//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 Z3>3&|&
_)2TLA
n3
类写好了,下面是在JSP中如下调用。 $ywh%OEH
+N:6wZ7<f
<% xGv,%'u\
CountBean cb=new CountBean(); ]},Q`n>$
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); J&65B./mD9
CountCache.add(cb); wg0.i?R-]
out.print(CountCache.list.size()+"<br>"); 9XvM%aHs:
CountControl c=new CountControl(); -Bv1}xf=6
c.run(); dt&Lwf/
out.print(CountCache.list.size()+"<br>"); l(\8c><m
%>