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: 8p91ni'
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CountBean.java Hzn6H4Rc
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/* !4?QR
* CountData.java h;+bHrKji
* |qp^4vq.p
* Created on 2007年1月1日, 下午4:44 SU8vz/\%y
* %o4d(C B
* To change this template, choose Tools | Options and locate the template under KKFV+bK)
* the Source Creation and Management node. Right-click the template and choose [v,Y-}wQ)
* Open. You can then make changes to the template in the Source Editor. t'7A-K=k3
*/ vrGx<0$
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package com.tot.count; r_p4pxs
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/** 7uI~Xo?N
* y}.?`/Q#
* @author
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*/ t,v=~LE
public class CountBean { x%$as;
private String countType; 4ayZ.`aK
int countId; )<>1Q{j@
/** Creates a new instance of CountData */ EN\
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public CountBean() {} (mR;MC
public void setCountType(String countTypes){ }O7!>T
this.countType=countTypes; pS) &d4i
} ]b&"](A
public void setCountId(int countIds){ vz87]InI
this.countId=countIds; zCuN8
} fG`<L;wi
public String getCountType(){ /XeCJxo8
return countType; ws_/F
} O{Y_j&1
public int getCountId(){ x&['g*[L0
return countId; 01brl^5K
} B]_NI=d
} Gc1!')g!
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CountCache.java DO5H(a
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/* k~|5TO
* CountCache.java /Y7YyjMi
* av; ~e<
* Created on 2007年1月1日, 下午5:01 8b!-2d:*
* LOPw0@
* To change this template, choose Tools | Options and locate the template under :krdG%r
* the Source Creation and Management node. Right-click the template and choose m7n8{J1O2
* Open. You can then make changes to the template in the Source Editor. $={^':Uh
*/ *D_p FS^l
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package com.tot.count; :#pfv)W6t
import java.util.*; [ELg:f3}5
/** s2N~p^
* 1P
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* @author 'v42Q J"{
*/ tl@n}
public class CountCache { =eB^(!M
public static LinkedList list=new LinkedList(); \0'0)@uziQ
/** Creates a new instance of CountCache */ | GqKa
public CountCache() {} 0DR:qw
public static void add(CountBean cb){ g"P!KPrf1p
if(cb!=null){ 4Ww.CkRG
list.add(cb); j3kcNb
} 4w)aAXK
} Q!&@aKl
} $,&3:ke1
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CountControl.java `{
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/* )=EJFQ*v
* CountThread.java "6}
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* +kdZfv>
* Created on 2007年1月1日, 下午4:57 mY& HK)
* [$+N"4
* To change this template, choose Tools | Options and locate the template under &nXa/XIZ_
* the Source Creation and Management node. Right-click the template and choose C EMe2~
* Open. You can then make changes to the template in the Source Editor. Ga9^+.j
*/ 7L"Pe'Hw
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package com.tot.count; r'/H3
import tot.db.DBUtils; rF>7
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import java.sql.*; FsXqF&{
/** N:]Ud(VRM
* 3R|C$+Sc
* @author +. ` I
*/ )8244;
public class CountControl{ ybNy"2Wk
private static long lastExecuteTime=0;//上次更新时间 /E|Ac&Qk
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 =w#sCy
/** Creates a new instance of CountThread */ uz8Y)b
public CountControl() {} 1|8<!Hx#-
public synchronized void executeUpdate(){ |mO4+:-~D+
Connection conn=null; >kN%R8*Sx
PreparedStatement ps=null; 6Pzz= ai<
try{ q,->E<8
conn = DBUtils.getConnection(); 9bVPMq7}i
conn.setAutoCommit(false); U$+G9
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Jd0I!L
for(int i=0;i<CountCache.list.size();i++){ MRn;D|Q
CountBean cb=(CountBean)CountCache.list.getFirst(); D3MRRv#
CountCache.list.removeFirst(); }0(.HMiGj
ps.setInt(1, cb.getCountId()); h,u?3}Knnb
ps.executeUpdate();⑴ zwEZ?m!
//ps.addBatch();⑵ 2TxHY|4
} dEuts*@Q
//int [] counts = ps.executeBatch();⑶ #y4+O;{
conn.commit(); Ki_8g
}catch(Exception e){ cf7UV6D g
e.printStackTrace(); hCX_^%
} finally{ <`/22S"
try{ 'A}@XGE:p
if(ps!=null) { Sph:OX8
ps.clearParameters(); $^XCI%DH
ps.close(); {G^f/%
ps=null; 3%'Y):
} xD|CQo}:
}catch(SQLException e){} N)tqjq
DBUtils.closeConnection(conn); w]ZE('3%W
} |5h~&kA
} iXJ3B&x
public long getLast(){ Xu+^41
return lastExecuteTime; v[UrOT:
} /O$7A7Tl
public void run(){ 6$k"B/k
long now = System.currentTimeMillis(); k9|8@3(h
if ((now - lastExecuteTime) > executeSep) { %l.5c Sn@
//System.out.print("lastExecuteTime:"+lastExecuteTime); BWHH:cX
//System.out.print(" now:"+now+"\n"); "F3M m
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); / ~\ I
lastExecuteTime=now; m+7/ebj{A
executeUpdate(); 0qPbmLMK
} Qv`Lc]'
else{ 1q Jz;\wU
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); aGRD`ra
} 8qi6>}A
} 6bXP{,}Gp
} TjswB#
//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 <8[y2|UBt
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类写好了,下面是在JSP中如下调用。 rCTH 5"
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<% 'Rg6JW\
CountBean cb=new CountBean(); /l)|B
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); pm 4"Q!K
CountCache.add(cb); f#mcWL1}
out.print(CountCache.list.size()+"<br>"); u#c3T'E
CountControl c=new CountControl(); (>
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c.run(); MkCq$MA
out.print(CountCache.list.size()+"<br>"); erW[q
%>