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: cV|u]ce%1
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CountBean.java _T8o]
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/* /8$*{ay
* CountData.java ?WD JWp%
* =r?#,'a
* Created on 2007年1月1日, 下午4:44 cq?&edjP
* p
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* To change this template, choose Tools | Options and locate the template under zJxO\
* the Source Creation and Management node. Right-click the template and choose T?!D?YV
* Open. You can then make changes to the template in the Source Editor. |mHxkd
*/ [H-r0Ah
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package com.tot.count; bOvMXj/HV=
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/** jE.yT(+lW
* @+iO0?f
* @author v +$3Z5
*/ 8D)I~0\
public class CountBean { 6 2YT)/i3
private String countType; q-k~L\Ys
int countId; }\-"L/D?+
/** Creates a new instance of CountData */ w%Bo7 'o)V
public CountBean() {} I7[F,xci
public void setCountType(String countTypes){ JsDugn ,B
this.countType=countTypes; e
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} c;M&;'#x
public void setCountId(int countIds){ Pl9Ky(Q`V
this.countId=countIds; "{1SDbwmMo
} Ho_ 2zx:8b
public String getCountType(){ Z` ;.62S
return countType; 6`V2-zv$
} 3Mlwq'pzD
public int getCountId(){ vwc)d{ND
return countId; 7y/Pch
} )|Il@unp/
} VK~ OL
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CountCache.java &OXnZT3P
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/* p,cw-lN
* CountCache.java #("/ 1N6
* @An "ClDa
* Created on 2007年1月1日, 下午5:01 O=A(x m#
* mqIcc'6f
* To change this template, choose Tools | Options and locate the template under Y,
?- []
* the Source Creation and Management node. Right-click the template and choose ruf*-&Kr7
* Open. You can then make changes to the template in the Source Editor. 3%J7_e'
*/ DXH"`1[-
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package com.tot.count;
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import java.util.*; CSBk
/** <gtqwH]
* G\I DgPj`
* @author s/"l ?d
*/ bq}hj Cy
public class CountCache { ^kF-mM=
public static LinkedList list=new LinkedList(); 'x{E#4A
/** Creates a new instance of CountCache */ *pZhwO!D
public CountCache() {} kv)IG$S0
public static void add(CountBean cb){ LY? `+/
if(cb!=null){ H:x{qS4Si
list.add(cb); xGU~FU
} iuxS=3lT"K
} /HiRbwQK#
} 3r]m8Hp
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CountControl.java iW\Q>~0#_
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/* REaU=-m-
* CountThread.java ~\C.Nm
* Js'#=
* Created on 2007年1月1日, 下午4:57 g6wL\g{29
* 55<f
* To change this template, choose Tools | Options and locate the template under eX1<zzd
* the Source Creation and Management node. Right-click the template and choose Px$4.b[{_Y
* Open. You can then make changes to the template in the Source Editor. fzhCV
*/ <,Z6=M`
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package com.tot.count; YR\pt8(z?
import tot.db.DBUtils; ?[`*z?}
import java.sql.*; WF!u2E+
/** ([+u U!
* j1sZRl)D
* @author u6pfc'GG g
*/ U,_jb}$Sq7
public class CountControl{ iFi6,V*PRt
private static long lastExecuteTime=0;//上次更新时间 2X@|H
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 1X7tN2tQ
/** Creates a new instance of CountThread */ -*QxZiKD
public CountControl() {} th 9I]g^=t
public synchronized void executeUpdate(){ ~dpU DF
Connection conn=null; 7w_cKR1;
PreparedStatement ps=null; l JR
try{ T`?{Is['(
conn = DBUtils.getConnection(); V7pe|]%r
conn.setAutoCommit(false); {~lVe GBp
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); RdtF5#\z
for(int i=0;i<CountCache.list.size();i++){ ;rK=
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CountBean cb=(CountBean)CountCache.list.getFirst(); UF$JVb
CountCache.list.removeFirst(); xKZLXQ'e-
ps.setInt(1, cb.getCountId()); kg@Okz N%
ps.executeUpdate();⑴ /@!%/Kl
//ps.addBatch();⑵ '%}k"&t$i
} nJ]oApb/-
//int [] counts = ps.executeBatch();⑶ (
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conn.commit(); FU~xKNr
}catch(Exception e){ &.ENcEic
e.printStackTrace(); aSy^(WN8
} finally{ wk'12r6=(-
try{ M
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if(ps!=null) { Q`Z=}^
ps.clearParameters();
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ps.close(); t[yu3U
ps=null; 0j--X?-
} ?df*Y5I2
}catch(SQLException e){} @'Y^A
DBUtils.closeConnection(conn); s_j ?L
} X:ck
} 5R?[My
public long getLast(){ ;B,6v P#
return lastExecuteTime; n*Q~<`T
} Q=+*OQV29
public void run(){ l[G&=/R@H
long now = System.currentTimeMillis(); h:J0d~u
if ((now - lastExecuteTime) > executeSep) { hyPVt6Gkj
//System.out.print("lastExecuteTime:"+lastExecuteTime); 3b#eB
//System.out.print(" now:"+now+"\n"); i 1{Lx)
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); =[7[F)I~O
lastExecuteTime=now; _3_kvs
executeUpdate(); L T.u<ThR}
} LrL
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else{ p;P"mp\'
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n");
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} AD** 4E
} [nx
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} Xv~v=.HNhk
//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 ks}J
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类写好了,下面是在JSP中如下调用。 &m8#^]*
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<% G1vg2'A
CountBean cb=new CountBean(); N3Yf3rK
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); [X"F}ph
CountCache.add(cb); fH#*r|~
out.print(CountCache.list.size()+"<br>");
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CountControl c=new CountControl(); 3.c0PRZ
c.run(); 8~~*/oCoJt
out.print(CountCache.list.size()+"<br>"); 9Ez>srH(
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