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: vuE 1(CR
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CountBean.java pN
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/* &6mXsx$
* CountData.java 5bKm)|4z6
* J$X{4
* Created on 2007年1月1日, 下午4:44 {"x8q
* K~B@8az
* To change this template, choose Tools | Options and locate the template under I "<ACM
* the Source Creation and Management node. Right-click the template and choose 6!GO{2d"
* Open. You can then make changes to the template in the Source Editor. OcWzo#q4[
*/ W<AxctId
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package com.tot.count; gwyHDSo8:a
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/** !.nyIA(
* -
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* @author <+wbnnK
*/ Dy[_Ix/Y,
public class CountBean { Anu`F%OzB
private String countType; ;m[-yqX
int countId; i)pAFv<$,
/** Creates a new instance of CountData */ H3{FiB]
public CountBean() {} '*6S0zt
public void setCountType(String countTypes){ <$]=Vaq
this.countType=countTypes; #M5R>&?Jqz
} ^t{2k[@
public void setCountId(int countIds){ .0b$mSV[
this.countId=countIds; dq&N;kk
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} ^t'mfG|DV
public String getCountType(){ :t36]NM
return countType; PfRe)JuB
} "ApVgNB
public int getCountId(){ 8IX,q
return countId; 7;T6hKWV[
} (`
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} cU^Z=B
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CountCache.java ~rWys=
*/ ~_ 3
/* vCB0x:/
* CountCache.java Y%B:IeF}
* W".: 1ov#B
* Created on 2007年1月1日, 下午5:01 [Pnk@jIk4
* _4]GP3`
* To change this template, choose Tools | Options and locate the template under ?Thh7#7LM
* the Source Creation and Management node. Right-click the template and choose LR5X=&k
* Open. You can then make changes to the template in the Source Editor. B?cn5
*/ $ MN1:ih
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package com.tot.count; N^{"k,vB-
import java.util.*; kDz!v?Z2+B
/** i^2yq&uT(
* Gidh7x
* @author !BocF<U E
*/ nF8|*}w
public class CountCache { KG!W,tB
public static LinkedList list=new LinkedList(); f`dQ $Kh
/** Creates a new instance of CountCache */ bCv^za]P6
public CountCache() {} f""+jc1
public static void add(CountBean cb){ cM= ?{W7~
if(cb!=null){ |NsrO8H
list.add(cb); aOj(=s
} 9F&s9(=\
}
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} P}AfXgr
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CountControl.java ,'KQF C
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/* _h=kjc}[.O
* CountThread.java M+mO4q6
* d'4^c,d
* Created on 2007年1月1日, 下午4:57 eiNF?](3O
* _wC4n }J
* To change this template, choose Tools | Options and locate the template under H1alf_(_
\
* the Source Creation and Management node. Right-click the template and choose h]6"~ m
* Open. You can then make changes to the template in the Source Editor. -jv%BJJlX
*/ +EtL+Y(U
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package com.tot.count; Q/y^ff]=
import tot.db.DBUtils; v7i5R !
import java.sql.*; B-@ ]+W
/** &K1\"
* ubpVrvu@
* @author k|Hxd^^I
*/ w _*|u
public class CountControl{ -t<8)9q(
private static long lastExecuteTime=0;//上次更新时间 O[tOpf@s.
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ]Tb ?k+a
/** Creates a new instance of CountThread */ Vh.9/$xQ
public CountControl() {} ^X&n-ui
public synchronized void executeUpdate(){ 7(q EHZEr
Connection conn=null; WxN@&g(
PreparedStatement ps=null; rW~hFSrV[o
try{ eC9nOwp]xH
conn = DBUtils.getConnection(); h;^H*Y&`
conn.setAutoCommit(false); 2W}f|\8MX
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 3M;[.b
for(int i=0;i<CountCache.list.size();i++){ FXHcy:)}G
CountBean cb=(CountBean)CountCache.list.getFirst(); {Q&@vbw'
CountCache.list.removeFirst(); zjzW;bo( d
ps.setInt(1, cb.getCountId()); Eagl7'x
ps.executeUpdate();⑴ >O{[w'sWa
//ps.addBatch();⑵ 7lo`)3mB
} k3-'!dW<
//int [] counts = ps.executeBatch();⑶ ;oKN 8vI#7
conn.commit(); :f~[tox
}catch(Exception e){ IsaL+elq|
e.printStackTrace(); O[N}@%HMW
} finally{ -FAAP&LG
try{ M!{;:m28X!
if(ps!=null) { O3?3XB> <
ps.clearParameters(); hU:M]O0uw
ps.close(); [@l:C\2
ps=null; ^[7ZB mS
} ),G?f {`!
}catch(SQLException e){} 5pOb;ry")`
DBUtils.closeConnection(conn); q,ry3Nr4n
} k63]Qf=5?N
} +w(sDH~kd
public long getLast(){ jLANv{"
return lastExecuteTime; P4M*vZq)
} d!V;\w
public void run(){ KRY%B[k
long now = System.currentTimeMillis(); {Hv/|.),hu
if ((now - lastExecuteTime) > executeSep) { &0E>&1`7
//System.out.print("lastExecuteTime:"+lastExecuteTime); h)W?8XdM
//System.out.print(" now:"+now+"\n"); X-tc Ud
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); BCw5.@HK*
lastExecuteTime=now; 6' 9ITA
executeUpdate(); ?r~|B/]
} VSK!Pc.G}
else{ _K4Igq
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); CXb-{|I}d
} 7O_@b$Q
} _I("k:E7
}
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//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 ` ^rN"\
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类写好了,下面是在JSP中如下调用。 QY]^^f
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<% 2D5S%27,
CountBean cb=new CountBean(); #].n0[
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ZyJdz+L{@V
CountCache.add(cb); kRCuc}:SB
out.print(CountCache.list.size()+"<br>"); 7^{M:kYC!
CountControl c=new CountControl(); ]h(}%fk_
c.run(); 6ty>0
out.print(CountCache.list.size()+"<br>"); $ekB+
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