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: #8S [z5 `
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CountBean.java ~o}moE/
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/* ])+Sc"g4k
* CountData.java H<v c\r
* |*lH9lWJ
* Created on 2007年1月1日, 下午4:44 A$%@fO.b
* Q~x*bMb.
* To change this template, choose Tools | Options and locate the template under >|v=Ba6R0
* the Source Creation and Management node. Right-click the template and choose p
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* Open. You can then make changes to the template in the Source Editor. t^`<*H
*/ luJ{Iq
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package com.tot.count; |3s.;wK
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/** l
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* 7~nIaT
* @author s4MNVT
*/ plzE
public class CountBean { _Jf J%YXy
private String countType; l*~"5f03
int countId; ~+sne7
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/** Creates a new instance of CountData */ U;x99Go:
public CountBean() {} Z)C:]}Ex
public void setCountType(String countTypes){ zyIza @V(
this.countType=countTypes; ;m-6.AV
} Ej;Vr~Wi
public void setCountId(int countIds){ ##SLwrg
this.countId=countIds; *O2^{ C
} Se!gs>
public String getCountType(){ cRs{=RGc
return countType; c.|sW2/
} 8Uj68Jl?
public int getCountId(){ {LR#(q$1
return countId; 6|B a
} U)&H.^@r$
} $M:4\E5(
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CountCache.java )_Z]=5Ds
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/* + TPbIRA
* CountCache.java T=hm#]
* 'US:Mr3
* Created on 2007年1月1日, 下午5:01 44Seq
* Y!K^-Y}
* To change this template, choose Tools | Options and locate the template under `DU'wB
* the Source Creation and Management node. Right-click the template and choose yb@X*PW/z
* Open. You can then make changes to the template in the Source Editor. (H|%?F;{l
*/ VWnu#_(
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package com.tot.count; F9>(W#aC
import java.util.*; 17MN8SfQ
/** )W_ Y3M,
* ,*9#c*'S
* @author z/c'Z#w%
*/ Y{x[N}h
public class CountCache { *~\;&G29Y
public static LinkedList list=new LinkedList(); @LwVmR |{
/** Creates a new instance of CountCache */ b;&Yw-\nZ;
public CountCache() {} `Gy>tD.#V-
public static void add(CountBean cb){ $6Q2)^LJ
if(cb!=null){ 7LyV`6{70
list.add(cb); cOj +}Hz58
} qiwQUm{
} $G^H7|PzdC
} \rw'QAi8r
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CountControl.java vZ1D3ytfG
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/* HnH2u;
* CountThread.java BMtYM{S6
* Q rrZF.
* Created on 2007年1月1日, 下午4:57 >o=axZNa
* (_s!,QUe
* To change this template, choose Tools | Options and locate the template under D9@<#2-
* the Source Creation and Management node. Right-click the template and choose ~@a) E+LsF
* Open. You can then make changes to the template in the Source Editor. P~b%;*m}8
*/ g*"J10hyP
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package com.tot.count; b_)QBE9
import tot.db.DBUtils; uMq\];7I
import java.sql.*; .PA?N{z
/** -Y!=Iw
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* dxae2 tV
* @author $yR{ZFo
*/ @eG#%6">
public class CountControl{ X~<>K/}u5
private static long lastExecuteTime=0;//上次更新时间 6w .iEb
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 0X}w[^f
/** Creates a new instance of CountThread */ !Cv<>_N).
public CountControl() {} `gA5P %
public synchronized void executeUpdate(){ R, (+NT$
Connection conn=null; ;r2b@x:<_
PreparedStatement ps=null; CM@"lV_
try{ 0lJBtk9wn
conn = DBUtils.getConnection(); N|^!"/
conn.setAutoCommit(false); 5u=U--
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); st1M.}
for(int i=0;i<CountCache.list.size();i++){ r(/P||`l
CountBean cb=(CountBean)CountCache.list.getFirst(); :u|UVp5
CountCache.list.removeFirst(); *SAcH_I2$>
ps.setInt(1, cb.getCountId()); HjETinm"
ps.executeUpdate();⑴ J[_?>YJ
//ps.addBatch();⑵ 4=#QN
} w-q=.RSTn=
//int [] counts = ps.executeBatch();⑶ CsQ}P)
conn.commit(); _#\5]D~""
}catch(Exception e){ N]<~NG:6b
e.printStackTrace(); 3 `C3+
} finally{ Ov{B-zCA
try{ J3!k*"P
if(ps!=null) { f|HgLFx
ps.clearParameters(); 8mQd*GGu1
ps.close(); m SvTnd8
ps=null; nG(|7x
} -^SD6l$
}catch(SQLException e){} )I0g&e^Tzy
DBUtils.closeConnection(conn); b "AHw?5F
} v*T@<]f3j
} ;tIIEc
public long getLast(){ 0$dY;,Q .
return lastExecuteTime; 'rcsK
} |Y,X=Ed
public void run(){ XQ?)
long now = System.currentTimeMillis(); W1M/Z[h6)5
if ((now - lastExecuteTime) > executeSep) { KTS7)2ci
//System.out.print("lastExecuteTime:"+lastExecuteTime); h11bK'TIv
//System.out.print(" now:"+now+"\n"); f<xt3
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); @o-evH;G
lastExecuteTime=now; ~NJL S-
executeUpdate(); hJtghG6v
} epm8N /
else{ l.t. ,:
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ,\">o vV33
} :O2v0Kx
} ]`+"o[
} {N8rZ [Oo
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 U S~JLJI
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类写好了,下面是在JSP中如下调用。 9cHNwgD>v
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<% Vt 5XC~jK
CountBean cb=new CountBean(); m:o$|7r
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); aG&kl O>m
CountCache.add(cb); Z_TbM^N
out.print(CountCache.list.size()+"<br>"); @eD2<e
CountControl c=new CountControl(); W71#NjM2Z
c.run(); ;R-Q,aCM}
out.print(CountCache.list.size()+"<br>"); 8CHf. SXh
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