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: o6}n8U}bk
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CountBean.java uDayBaR
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/* !/I0i8T
* CountData.java zAScRg$:?
* oq;'eM1,.
* Created on 2007年1月1日, 下午4:44 YaY8 `M{
* @Doyt{|T
* To change this template, choose Tools | Options and locate the template under =AOWeLk*G
* the Source Creation and Management node. Right-click the template and choose Xl%0/o
* Open. You can then make changes to the template in the Source Editor. 9E1W|KE
*/ \ijMw
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package com.tot.count; Qv#]81i(1
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/** i$UQbd
* HJhH-\{@
* @author y,m2(V
*/ sR_xe}-
public class CountBean { {'bip`U.
private String countType; 7*+TP~WI
int countId;
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/** Creates a new instance of CountData */ smU4jh9S
public CountBean() {} G '#41>q+
public void setCountType(String countTypes){ g9mG`f
this.countType=countTypes; Hs?zq
} ~OFvu}]
public void setCountId(int countIds){ G<qIY&D'
this.countId=countIds; G?hK9@ |v
} h##WA=1QZ
public String getCountType(){ kv?|'DN
return countType; +=3CL2{An
} H[Weu
public int getCountId(){ 6yIvaY$KR
return countId; cT'w=
} GJQc!cqk
} (ku5WWJ
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CountCache.java \t.}-u<7{
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/* <$E6oZ
* CountCache.java faJM^ u
* *\XH+/]+
* Created on 2007年1月1日, 下午5:01 bEH
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* 8^yJqAXK
* To change this template, choose Tools | Options and locate the template under f7<pEGb
* the Source Creation and Management node. Right-click the template and choose FGanxv@15
* Open. You can then make changes to the template in the Source Editor. 3h=8"lRc
*/ TI9X.E?
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package com.tot.count; &0v.E"0<
import java.util.*; H{`{)mS
/** (Mt5 P
* r%=[},JQ
* @author _p}xZD\?,
*/ +m$5a
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public class CountCache { #V_GOy1-
public static LinkedList list=new LinkedList(); VWf %v
/** Creates a new instance of CountCache */ /iM$Tb5
public CountCache() {} YUkud2,j
public static void add(CountBean cb){ <,8l *1C
if(cb!=null){ 2qj{n+
list.add(cb); 4A.Q21s
} (GU9p>2
} lAASV{s{
} 4tc:.
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CountControl.java F9Z@x)
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/* xHkxc}h
* CountThread.java Ka-p& Uv1<
* `~F5wh~
* Created on 2007年1月1日, 下午4:57 |:q/Dt@
* q&si%
* To change this template, choose Tools | Options and locate the template under _PXdzeI.
* the Source Creation and Management node. Right-click the template and choose 3fkk
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* Open. You can then make changes to the template in the Source Editor. t@B(+
*/ mh`|=M]8E
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package com.tot.count; hKe30#:v
import tot.db.DBUtils; T~>#2N-Z
import java.sql.*; %%}A|,
/** lpC
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* +1`t}hO
* @author 9`Q@'(m
*/ Wk7WK` >i
public class CountControl{ %FA@)?~
private static long lastExecuteTime=0;//上次更新时间 Fvl`2W94;
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 h%}(h2W
/** Creates a new instance of CountThread */ yp]@^T N
public CountControl() {} }KB[B
public synchronized void executeUpdate(){ Zk`#VH
Connection conn=null; X"*^l_9-v
PreparedStatement ps=null; tL(B pL'
try{ H%i>L?J2 /
conn = DBUtils.getConnection(); x0+glQrNN
conn.setAutoCommit(false); LI
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); !`wW_W
for(int i=0;i<CountCache.list.size();i++){ *e4TSqC|
CountBean cb=(CountBean)CountCache.list.getFirst(); r/r:oXK
CountCache.list.removeFirst(); O!F]^'!
ps.setInt(1, cb.getCountId()); zK5bO=0j
ps.executeUpdate();⑴ .{so
//ps.addBatch();⑵ }C#3O{5
} vq6%Ey3Gix
//int [] counts = ps.executeBatch();⑶ ygViPz<J
conn.commit(); ;=;JfNnbm
}catch(Exception e){ b:MG@Hxc
e.printStackTrace(); *|RS*ABte
} finally{ XD%wj
try{ 46XN3r
if(ps!=null) { =uV,bG5V1
ps.clearParameters(); yYTVXs`fVj
ps.close(); A"l{?;~
ps=null; \"^%90F
} ~"dhu]^
}catch(SQLException e){} `a4 $lyZ
DBUtils.closeConnection(conn); RQ'
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} A WJWtUa
} {d!Y3+I%G
public long getLast(){ ^ddO&!U
return lastExecuteTime; <^><3U`
} bLS&H[fK
public void run(){ m_lrPY-
long now = System.currentTimeMillis(); v'ay.oVzw
if ((now - lastExecuteTime) > executeSep) { =>LZm+P
//System.out.print("lastExecuteTime:"+lastExecuteTime); RU_L<Lpi
//System.out.print(" now:"+now+"\n"); ME+em1ZH
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); S+I^!gT
lastExecuteTime=now; AV4~U:vU
executeUpdate();
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} 2$0)?ZC?=
else{ l5J.A@0
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 8LrK94
} `wO}Hz
} 7
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} nX[;^v/
//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 ZKdh%8C
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类写好了,下面是在JSP中如下调用。 >)c9|e=8
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<% ]+%=@mWYs
CountBean cb=new CountBean(); 77aX-e*=E
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); +{-]P\oc
CountCache.add(cb); F)ci9- b@
out.print(CountCache.list.size()+"<br>"); VifmZ;S@Y
CountControl c=new CountControl(); MOHHZApt
c.run(); J r*"V`
out.print(CountCache.list.size()+"<br>"); A7Y_HIo
%>