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: CM t$)
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CountBean.java .fK~IKA
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/* c#@L~<
* CountData.java \t? ;p-+ta
* !HXyvyDN
* Created on 2007年1月1日, 下午4:44 -1ci.4F&
* v(,YqT>q@U
* To change this template, choose Tools | Options and locate the template under {RD9j1
* the Source Creation and Management node. Right-click the template and choose f3<2531/}
* Open. You can then make changes to the template in the Source Editor. BiZYGq
*/ tw]
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package com.tot.count; q~{O^,4S
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/** w!}kcn<
* hzh3p[
* @author $]a*ZHd;2&
*/ r_o\72
public class CountBean { X#X/P
private String countType; J~N!. i
int countId; MI`<U:-lP
/** Creates a new instance of CountData */
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public CountBean() {} [5GzY`/m
public void setCountType(String countTypes){ 8boiJku`
this.countType=countTypes; hl,x|.f}4Y
} `J;g~#/k
public void setCountId(int countIds){ 1TgD;qX
this.countId=countIds; +77j2W_0
} :2~2j-m
public String getCountType(){ #6#%y~N
return countType; 2=|Ks]<P
} Jb)xzUhES
public int getCountId(){
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return countId; oYWHO<b
} U:|:Y=O?Q
} (
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CountCache.java Yv[<c!\
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/* ]hbrzvo
* CountCache.java i1Y<[s
* o%$R`;
* Created on 2007年1月1日, 下午5:01 p`'3Il3
* )0=H)k0
* To change this template, choose Tools | Options and locate the template under ]zI*}(adu
* the Source Creation and Management node. Right-click the template and choose ;NGSJfn
* Open. You can then make changes to the template in the Source Editor. 66po SZR@
*/ k?_uv
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package com.tot.count; ]'z 5%'
import java.util.*; `a@YbuLd
/** ];QX&";Z
* +t(Gt0+
* @author !{A#\~,
*/ Jn20^YG
public class CountCache { :6Gf@Z&+
public static LinkedList list=new LinkedList(); iq5-eJmq
/** Creates a new instance of CountCache */ W QeQ`pM
public CountCache() {} ~le:4qaX
public static void add(CountBean cb){ 880T'5}S
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if(cb!=null){ %~N| RSec
list.add(cb); \M*c3\&~,e
} gi8f)MNP?~
} f;bfR&v
} ~Vc`AcWP
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CountControl.java WH.3
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/* O/oLQoH
* CountThread.java 161IWos
* |
* Created on 2007年1月1日, 下午4:57 Q%0
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* M[0NB2`Wp
* To change this template, choose Tools | Options and locate the template under 9]|C$;kw@
* the Source Creation and Management node. Right-click the template and choose y!~ }7=
* Open. You can then make changes to the template in the Source Editor. (^~~&/U_U$
*/ +y 48.5
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package com.tot.count; ZD<e$PxxCd
import tot.db.DBUtils; O
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import java.sql.*; 3WPZZN<K9
/** /WI H#M
* t1!>EI`
* @author kU{a!ca4
*/ ,/dW*B
public class CountControl{ es\Fn#?O
private static long lastExecuteTime=0;//上次更新时间 @$;I%
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 0fN;
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/** Creates a new instance of CountThread */ 26=G%F6
public CountControl() {} } ;d=
public synchronized void executeUpdate(){ Z 3-=TN
Connection conn=null; |zy` ]p9
PreparedStatement ps=null; z :A_
try{ :VX2&*
conn = DBUtils.getConnection(); BfD C[(n`
conn.setAutoCommit(false); L!Gpk)}[i
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); nlc$"(eA[H
for(int i=0;i<CountCache.list.size();i++){ ^a7a_M
CountBean cb=(CountBean)CountCache.list.getFirst(); kXOc)
CountCache.list.removeFirst(); lXutZ<S[
ps.setInt(1, cb.getCountId()); M'@
ps.executeUpdate();⑴ 4!-/m7%eF
//ps.addBatch();⑵ ah#jvp
} @/='BVb'T
//int [] counts = ps.executeBatch();⑶ BoHNni
conn.commit(); }RUK?:lEA
}catch(Exception e){ cEGR?4z
e.printStackTrace(); XM`&/)
} finally{ B3E}fQm )
try{ yB4eUa!1
if(ps!=null) { {3``B#}
ps.clearParameters(); 9r 5(
ps.close(); <9S 5
ps=null; ;S'1fci6
} x}O J~Yk]
}catch(SQLException e){} NOl/y@#
DBUtils.closeConnection(conn); 8>|<m'e^\r
} $|I hO
} nHQWO
public long getLast(){ qU ,{jD$
return lastExecuteTime; p & i+i
} MSe>1L2=
public void run(){ ;Ao`yC2(v
long now = System.currentTimeMillis(); sRC?l_n;
if ((now - lastExecuteTime) > executeSep) { S) `@)sr
//System.out.print("lastExecuteTime:"+lastExecuteTime); qCm8R@
//System.out.print(" now:"+now+"\n"); n9V8A[QJ
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 5e^z]j1Yv
lastExecuteTime=now; 5a:YzQ4
executeUpdate(); OUy}1%HY
} <'~6L#>,<
else{ "7w=LhzV[$
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 'T]Ok\
} %<MI]D
} HE+D]7^
} PVrNS7 Rk/
//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 O{EbL5p
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类写好了,下面是在JSP中如下调用。 Q>WnSm5R
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<% 3o#K8EL
CountBean cb=new CountBean(); Ba76~-gK$
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 8o466m6/
CountCache.add(cb); =h/61Bl3
out.print(CountCache.list.size()+"<br>"); 0hq\{pw_y*
CountControl c=new CountControl(); 8TYoa:pZ
c.run(); <m%ZDOMa
out.print(CountCache.list.size()+"<br>"); m"
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%>