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: fjwUh>[ }
^s[OvJb
CountBean.java /By`FW Y
dp'xd>m
/* R7j'XU
* CountData.java }!n90
9L
* /\C5`>x
* Created on 2007年1月1日, 下午4:44 ?> 7SZiC`
* R<AT}!mkR
* To change this template, choose Tools | Options and locate the template under 6i.!C5YX]
* the Source Creation and Management node. Right-click the template and choose Y[WL}:"93
* Open. You can then make changes to the template in the Source Editor. UYW{AG2C
*/ [ yf&]0
g?=|kp
package com.tot.count; %}x$YDO
=V(|3?N
/** Wp0L!X=0
* \]gUX-
* @author Al 1BnFB
*/ *&A/0]w
public class CountBean { mw,\try
private String countType; ,oS<9kC68
int countId; 2\, h "W(
/** Creates a new instance of CountData */ lhRo+X#G
public CountBean() {} w=MiJr#3^
public void setCountType(String countTypes){ Q@HW`@i
this.countType=countTypes; 8M9}os
} $yY\[C
public void setCountId(int countIds){ i$bHet
this.countId=countIds; u#s br8Y
} b2p;-rv
public String getCountType(){ >t Ll|O+
return countType; 1e(QI)
~
} 0^IHBN?9
public int getCountId(){ 1`z^Xk8vt
return countId; g Xi&
S
} NP_b~e6O=
} _b(y"+k
LtIw{*3
CountCache.java %A ^qm
e+ckn
/* pg:1AAhT[
* CountCache.java ="=Aac#n`
* vx&r
* Created on 2007年1月1日, 下午5:01 @&
vtY._
* 2^.qKY@g@
* To change this template, choose Tools | Options and locate the template under ZN]LJ4|xu
* the Source Creation and Management node. Right-click the template and choose Am&PH(}L
* Open. You can then make changes to the template in the Source Editor. e6JT|>9A7
*/ n0*a.
f+o%N
package com.tot.count; Pk6l*+"r<
import java.util.*; B[Gl}(E
/** knU=#
* ;[}<xw3):
* @author .o?"=Epo
*/ \gE6KE<?p
public class CountCache { u(92y]3,
public static LinkedList list=new LinkedList(); `+>'18F
/** Creates a new instance of CountCache */
S_EN,2'e
public CountCache() {} Nt^9N
#+N
public static void add(CountBean cb){ Y
Cbt(nmr
if(cb!=null){ %/r}_V(UN
list.add(cb); !J@!P?0. C
} /18VQ
} PpF"n[j
} (g>>
+>,4d
CountControl.java ~ d!F|BH4
/^F$cQX(
/* ]IZn#gnM
* CountThread.java ',<Bo{
* +zz\*
* Created on 2007年1月1日, 下午4:57 X\dPQwasM
* w?LDaSz\t
* To change this template, choose Tools | Options and locate the template under l0%qj(4`6&
* the Source Creation and Management node. Right-click the template and choose N-g=_86C"
* Open. You can then make changes to the template in the Source Editor. [LHx9(,NM
*/ LQs>[3rK
hQT
p&
package com.tot.count; O=Cz*j
import tot.db.DBUtils; |re>YQ!zd
import java.sql.*; ?z]hYsy
/** -(Y( K!n
* ![OKmy
* @author 7Y>17=|
*/ ;[ag|YU$Y
public class CountControl{ #'<s/7;~
private static long lastExecuteTime=0;//上次更新时间 $<[Q8V-
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 9]DMHA@
/** Creates a new instance of CountThread */ L-}6}5[
public CountControl() {} x\r[Zp|
public synchronized void executeUpdate(){ A_mVe\(*M
Connection conn=null; $aFCe}3b<
PreparedStatement ps=null; >#Obhs|S{C
try{ \k69 S/O
conn = DBUtils.getConnection(); +UGWTO\#ha
conn.setAutoCommit(false); xpb,Nzwt^
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); NLz[F`I
for(int i=0;i<CountCache.list.size();i++){ E>}(r%B
CountBean cb=(CountBean)CountCache.list.getFirst(); F/ODV=J-
CountCache.list.removeFirst(); PqOPRf
ps.setInt(1, cb.getCountId());
{"([p L
ps.executeUpdate();⑴ IJ`%Zh{f
//ps.addBatch();⑵ FYs-vW {
} }eO{+{D+
//int [] counts = ps.executeBatch();⑶ jM'kY|<g;
conn.commit(); &H`A S6
}catch(Exception e){ TI9]v(
e.printStackTrace(); :E>"z6H
} finally{ HL^+:`,
try{ tlnU2TT_f
if(ps!=null) { 0E5"}8
ps.clearParameters(); *88Q6=Mm
ps.close(); E W{vF|
ps=null; :=iP_*#
} 8?>
#
}catch(SQLException e){} vl"l
DBUtils.closeConnection(conn); cen[|yCtOH
} Pr%Y!|
} m@z.H ;
public long getLast(){ YA:7^-Bv
return lastExecuteTime; %ZajM
} $@[`v0y*
public void run(){ c89+}]mGq
long now = System.currentTimeMillis(); <h*r
if ((now - lastExecuteTime) > executeSep) { xDU{I0M
//System.out.print("lastExecuteTime:"+lastExecuteTime); 4NY}=e5
//System.out.print(" now:"+now+"\n"); >+P5Zm(_
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); R@+%~"Z
lastExecuteTime=now; X &z|im'd
executeUpdate(); vIL'&~C\y
} kma)DW
else{ Qrnc;H9)
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); !Rq.L
} 1TagQ
} <yw6Om:n<
} 7H+IW4Ma
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 8K]5fkC|
"zn<\z$l
类写好了,下面是在JSP中如下调用。 * 7<{Xbsj^
0I`)<o-
<% Cm~Pn"K_]
CountBean cb=new CountBean(); g p2S
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 2+2Gl7" s
CountCache.add(cb); /{[Y l[{"<
out.print(CountCache.list.size()+"<br>"); DxFmsjX[L
CountControl c=new CountControl(); S^Lu RF]F
c.run(); rW8.bMmM
out.print(CountCache.list.size()+"<br>"); *Va ;ra(V2
%>