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: C6VLy x
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CountBean.java BBaQ}{F8>2
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/* 51#_Vg
* CountData.java "i
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* N:S/SZI
* Created on 2007年1月1日, 下午4:44 |t^E~HLm,
* caU0\VS
* To change this template, choose Tools | Options and locate the template under o*b] p-
* the Source Creation and Management node. Right-click the template and choose 1#C4;3i,
* Open. You can then make changes to the template in the Source Editor. 6"wlg!k8
*/ b LB:MW\%
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package com.tot.count; 7r7YNn/?
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/** y=fx%~<>
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* )P%ZA)l%_o
* @author w{Ivmdto
*/ #H)vK"hF
public class CountBean { VQ(j pns5
private String countType; IshKH-
int countId; ~Y `ldL
/** Creates a new instance of CountData */ y0Fb_"}
public CountBean() {} Dl<bnx;0
public void setCountType(String countTypes){ sGi"rg#
this.countType=countTypes; P60~V"/P
} ./-5R|fN
public void setCountId(int countIds){ hcgMZT!<5
this.countId=countIds; O@tU.5*$5
} ,-$LmECg
public String getCountType(){ NokU)O ;x
return countType; GOj-)i/_
}
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public int getCountId(){ ;%B(_c
return countId; cbNTj$'b2u
} }K7#Q
} +Jlay1U&
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CountCache.java <C_jF
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/* +M./@U*g
* CountCache.java t=(!\:[D
* &c` nR<
* Created on 2007年1月1日, 下午5:01 !Xh=k36
* ]jtK I4
* To change this template, choose Tools | Options and locate the template under o~U$GBg
* the Source Creation and Management node. Right-click the template and choose ,MdV;j~"'
* Open. You can then make changes to the template in the Source Editor. F<ZYh
*/ &D>G8
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package com.tot.count; )s)I2Z+
import java.util.*; H~oail{EQ
/** XQrF4l
* QMA%$
* @author _mzW'~9wN
*/ gcii9vz
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public class CountCache { m- %E-nr
public static LinkedList list=new LinkedList(); fsmN)_T
/** Creates a new instance of CountCache */ P!~MZ+7#&
public CountCache() {} sW Qfr$^A
public static void add(CountBean cb){ QgrpBG
if(cb!=null){ Z_PNI#h*
list.add(cb); :lX!\(E2
} hv)x=e<
} @+;$jRwq
} _U$<xVnP
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CountControl.java
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/* =Ee&da^MB
* CountThread.java Gn22<C/
* B5gj_^
* Created on 2007年1月1日, 下午4:57 jAGTD I
* ,f kcp]}
* To change this template, choose Tools | Options and locate the template under .v]IJfRH*
* the Source Creation and Management node. Right-click the template and choose @M<|:Z %.@
* Open. You can then make changes to the template in the Source Editor. _G_Cj{w
*/ osciZ'~
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package com.tot.count; T`/AY?#
import tot.db.DBUtils; <i<J^-W
import java.sql.*; 2:*w~|6>}5
/** 5VRYO"D:
* y9_V
* @author 2^XGGB0
*/ ZjT,pOSyb
public class CountControl{ -1Jg?cPzk
private static long lastExecuteTime=0;//上次更新时间 Pl(Q,e7O]
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 SD#]$v
/** Creates a new instance of CountThread */ $JS L-NkE
public CountControl() {} d; [C6d
public synchronized void executeUpdate(){ T}
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Connection conn=null; g6nkZyw
PreparedStatement ps=null; 6L:x^bM
try{ ml2_
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conn = DBUtils.getConnection(); xE1 eT,
conn.setAutoCommit(false); yH7F''O7
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); d[r#-h>dS
for(int i=0;i<CountCache.list.size();i++){ &9/O!3p)
CountBean cb=(CountBean)CountCache.list.getFirst(); ;g8R4!J
CountCache.list.removeFirst(); dCb`xR}
ps.setInt(1, cb.getCountId()); bAsYv*t%r
ps.executeUpdate();⑴ tv>>l%
//ps.addBatch();⑵ 832v"kCD
} \Fl+\?~D
//int [] counts = ps.executeBatch();⑶ wU8Mt#D!
conn.commit(); ;sfb 4x4
}catch(Exception e){ QS0:@.}$E)
e.printStackTrace(); ?:Mr=]sD
} finally{ ^F>cp
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try{ _a_7,bk5
if(ps!=null) { 0YaA `
ps.clearParameters(); @*>@AFnf\Z
ps.close(); _AYXc] 4%
ps=null; =b38(\
} mt9.x
}catch(SQLException e){} |}23>l7
DBUtils.closeConnection(conn); "~`I::'c
} n 9\
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} UU'|Xz9~
public long getLast(){ f @8mS
return lastExecuteTime; wNq;;AJ$
} `{,Dy!rL
public void run(){ ag$Vgl
long now = System.currentTimeMillis(); R,)}>X|<
if ((now - lastExecuteTime) > executeSep) { 1[kMOp
//System.out.print("lastExecuteTime:"+lastExecuteTime); ?P4w]a
//System.out.print(" now:"+now+"\n"); rxr{/8%f%
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); (Lo%9HZ1Mx
lastExecuteTime=now; ~i@Y|38C
executeUpdate(); FSU ttg"
} y'FS/=u>0
else{ tcI}Ca>u
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); wg ^sGKN
} J~%K_~Li
} K6y :mJYp\
} xAafm<L@!
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 aqYa{hXio
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类写好了,下面是在JSP中如下调用。 XEC(P
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CountBean cb=new CountBean(); !(qsD+
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); i.=w]S
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CountCache.add(cb); [(o7$i29|%
out.print(CountCache.list.size()+"<br>"); uqM yoIc
CountControl c=new CountControl(); @)-sTgn
c.run(); ;GVV~.7/
out.print(CountCache.list.size()+"<br>"); #BJG9DFP4`
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