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: tw/dD +
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CountBean.java ()?(I?II
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/* v{N`.~,^
* CountData.java u4?L 67x
* 2MIi=c:oqK
* Created on 2007年1月1日, 下午4:44 M
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* BwpqNQN
* To change this template, choose Tools | Options and locate the template under MKk\
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* the Source Creation and Management node. Right-click the template and choose B dfwa
* Open. You can then make changes to the template in the Source Editor. xm~`7~nFR
*/ An0|[ uWH
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package com.tot.count; 4k1xy##
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/** G>}255qY
* AV]2euyn
* @author my1@41
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*/ JyK3{wYS
public class CountBean { *:7rdzn
private String countType; cqkV9f8Ro
int countId; qYQl,w
/** Creates a new instance of CountData */ !9e=_mY
public CountBean() {} ~G&dqw/.-U
public void setCountType(String countTypes){ `/+>a8
this.countType=countTypes; %aCqi(.7
} i1d'nxk6
public void setCountId(int countIds){ EME|k{W
this.countId=countIds; ]s'as9s9
} `$9x 1dx
public String getCountType(){ a58H9w"u)
return countType; qInR1 r<
} 9W5lSX#^;
public int getCountId(){ *N<]Xy@
return countId; WpP}stam/
} V f&zL
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} FD
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CountCache.java F/{!tx
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/* Sz`,X0a
* CountCache.java RtS+<^2a;
* ? OM!+O
* Created on 2007年1月1日, 下午5:01 1CZgb
* `U_)98
* To change this template, choose Tools | Options and locate the template under 6d}lw6L
* the Source Creation and Management node. Right-click the template and choose 8TKnL\aar
* Open. You can then make changes to the template in the Source Editor. V}CG:9;
*/ cuITY^6
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package com.tot.count; tcI*a>
import java.util.*; (?c"$|^J
/** Rhs/3O8k
* 7n<{tM
* @author
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*/ j,eo2HaL
public class CountCache { Zu[su>\
public static LinkedList list=new LinkedList(); q]-r@yF
/** Creates a new instance of CountCache */ b8UO,fY q
public CountCache() {} #c!lS<z
public static void add(CountBean cb){ Ld~/u]K%V
if(cb!=null){ C&%_a~
list.add(cb); {VRf0c
} "KpGlY?^
} H7n>Vx:L-
} Q)h(nbbVak
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CountControl.java k y7Gwc
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/* vk^xT
* CountThread.java H1./x6Hr
* 1Pu~X
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* Created on 2007年1月1日, 下午4:57 lL3U8}vn
*
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* To change this template, choose Tools | Options and locate the template under Jnov<+
* the Source Creation and Management node. Right-click the template and choose T8$y[W-c
* Open. You can then make changes to the template in the Source Editor. A;M'LM- M
*/ u6JM]kR
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package com.tot.count; Svmy(w~m
import tot.db.DBUtils; #X1ND
import java.sql.*; |Rk@hzM2S
/** DvvK^+-~
* Z FL~;_r
* @author )y$(AJx$
*/ 46h<,na?,
public class CountControl{ F JyT+
private static long lastExecuteTime=0;//上次更新时间 q_58;Bv
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 (!WD1w
/** Creates a new instance of CountThread */ nNn:-
public CountControl() {} :vbW
public synchronized void executeUpdate(){ O\r0bUPE
Connection conn=null; ~9@UjQ^)F
PreparedStatement ps=null; 6i/(5 nQ
try{ .ioEIs g
conn = DBUtils.getConnection(); b]KBgZ
conn.setAutoCommit(false); R\[e!g*I
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); G"t5nHY\.
for(int i=0;i<CountCache.list.size();i++){ a:w#s}bL
CountBean cb=(CountBean)CountCache.list.getFirst(); j#ab_3xH
CountCache.list.removeFirst(); ^1];S^nD
ps.setInt(1, cb.getCountId()); G 3ptx!
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ps.executeUpdate();⑴ NgPk&niM
//ps.addBatch();⑵ bk[!8-b/a
} NzvXN1_%
//int [] counts = ps.executeBatch();⑶ +I28|*K"
conn.commit(); dy[X3jQB
}catch(Exception e){ (sZ"iGn%
e.printStackTrace(); 6'f;-2
} finally{ ckCE1e>s
try{ D0f] $
if(ps!=null) { WpvhTX
ps.clearParameters(); 3bI9Zt#J%&
ps.close(); <a3WKw
ps=null; "w<#^d_6
} R:qW;n%AF
}catch(SQLException e){} ZN0P:==
DBUtils.closeConnection(conn); ~P-mC@C
} |FRg\#kf%
} [nq@m c~<
public long getLast(){ v]UwJz3<
return lastExecuteTime; /)O"l @ }U
} xAm6BB
c
public void run(){ a%0EiU
long now = System.currentTimeMillis(); $F.a><1rY
if ((now - lastExecuteTime) > executeSep) {
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//System.out.print("lastExecuteTime:"+lastExecuteTime); dM@1l1h/
//System.out.print(" now:"+now+"\n"); C0Z=~Q%
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); d<Tc7vg4|U
lastExecuteTime=now; {'H(g[k
executeUpdate(); \ Cj7k^
} f|gg
else{ aN3;`~{9
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); HGg@ _9tW
} )4 ;`^]F
} 0"z9Q\{}
} ,V}WM%Km
//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 qH_Dc=~la
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类写好了,下面是在JSP中如下调用。 u*9V&>o
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<% 1o>xEWt:0K
CountBean cb=new CountBean(); veECfR;
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 47/iF97
CountCache.add(cb); tZo} ;|~'
out.print(CountCache.list.size()+"<br>"); '|=;^Z7.K
CountControl c=new CountControl(); zm;C\s rF
c.run(); GC'O[q+
out.print(CountCache.list.size()+"<br>"); 2Tppcj v
%>