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: Z~DR,:
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CountBean.java rFYw6&;vOi
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/* {us"=JJVN
* CountData.java lNqF@eCT9
* CWM_J9f
* Created on 2007年1月1日, 下午4:44 ~ ^)4*@i6
* l\~F0Z/O
* To change this template, choose Tools | Options and locate the template under i^&^eg'.5
* the Source Creation and Management node. Right-click the template and choose &13#/
* Open. You can then make changes to the template in the Source Editor. ,c[f/sT\
*/ :%"$8o*0W
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package com.tot.count; 2k"!o~s^
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/** C2W&*W*
* 3X}>_tj
* @author %8T"h
*/ UU]a).rz
public class CountBean { +[$ Q C*
private String countType; vrvOPLiQ
int countId; _0qp!-l}
/** Creates a new instance of CountData */ Py-}tFr
public CountBean() {} _tpqo>
public void setCountType(String countTypes){ f hr
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this.countType=countTypes; <>^otb,e$
} lAx^!#~\
public void setCountId(int countIds){ ?DKwKt
this.countId=countIds; ;Fm7!@u^0
} F<A[S"
public String getCountType(){ TTzvH;S
return countType; O{nM
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} I]Jz[{~1
public int getCountId(){ @j?)uJ0Q
return countId; ,.&y-?
} OO`-{HKt
} haIH `SY
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CountCache.java 0|@*`-:VO
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/* FTC,{$
* CountCache.java G,JNUok
* sc
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* Created on 2007年1月1日, 下午5:01 fr([g?F%D
* ,xsFBNCC
* To change this template, choose Tools | Options and locate the template under )%]`uj>*[
* the Source Creation and Management node. Right-click the template and choose 2/V9Or52
* Open. You can then make changes to the template in the Source Editor. z\?cazQ
*/ WEFvJ0]
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package com.tot.count; b)Dzau
import java.util.*; &Ew{ {t;"
/** dUL3UY3
* DZ~qk+,I
* @author \1b! I)T9
*/ LHJjPf)F
public class CountCache { Z 361ko}
public static LinkedList list=new LinkedList(); Ud[Zv?tA:
/** Creates a new instance of CountCache */ "] 0sR
public CountCache() {} a}MSA/K(
public static void add(CountBean cb){ ^+zhzfJ
if(cb!=null){ +Q6}kbDI
list.add(cb); XhEd9>#
} maR5hgWCHe
} ([a[fi
} DKxzk~sOM
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CountControl.java ts3BmfR?
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/* 3G)Wmmh"a
* CountThread.java XF 8$D
* Y>i?nC%*
* Created on 2007年1月1日, 下午4:57 0755;26Bx
* KM;'MlO
* To change this template, choose Tools | Options and locate the template under 7BDRA},o
* the Source Creation and Management node. Right-click the template and choose ?XNQ_m8f
* Open. You can then make changes to the template in the Source Editor. 8rx"D`{|
*/ WbW@V_rr
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package com.tot.count; jk'.Gz
import tot.db.DBUtils; (( D*kd"
import java.sql.*; T,eP&IN
/** ,3tcti~sZ
* A$]&j5nh|
* @author V)8d1S
*/ ,Bg)p_B
public class CountControl{ }^np
private static long lastExecuteTime=0;//上次更新时间 UBy<
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 kxp, ZP
/** Creates a new instance of CountThread */ g1s\6%g
public CountControl() {} b;XUv4~V
public synchronized void executeUpdate(){ *.]M1
Connection conn=null; Dtw1q-
PreparedStatement ps=null; >uN)O-
try{ rG*Zp7{
conn = DBUtils.getConnection(); >u:t2DxE
conn.setAutoCommit(false); ~@wM[}ThP$
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); g:sn/Zug]
for(int i=0;i<CountCache.list.size();i++){ 6*n<emP
CountBean cb=(CountBean)CountCache.list.getFirst(); SuU_psF
CountCache.list.removeFirst(); zrg#BXj7
ps.setInt(1, cb.getCountId()); _b8?_Zq
ps.executeUpdate();⑴ 8I`t`C/4
//ps.addBatch();⑵ \Gk4J<
} E8=8OX/{Y
//int [] counts = ps.executeBatch();⑶ r)G^V&96
conn.commit(); TsB"<6@!AA
}catch(Exception e){ "/&_B
e.printStackTrace(); ~Yw`w2
} finally{ ZFAi 9M
try{ ;Xw'WMb*=
if(ps!=null) { "+6:vhP5
ps.clearParameters(); |E YJbL;1%
ps.close(); ]'2;6%.4
ps=null; LK1 r@
} ~K-c-Zs#z
}catch(SQLException e){} 8>
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DBUtils.closeConnection(conn); o"a~
} [o0Z;}fU
} {T0f]]}Q
public long getLast(){ K9YD)351t
return lastExecuteTime; '9Hah
} IP]"D"
public void run(){ 8 N5ga
long now = System.currentTimeMillis(); (A\p5@ht
if ((now - lastExecuteTime) > executeSep) { xA-u%Vf7@
//System.out.print("lastExecuteTime:"+lastExecuteTime); Wp[R$/uT
//System.out.print(" now:"+now+"\n"); ` 5.PPI\h2
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); UE[5Bw?4X
lastExecuteTime=now; cCoa3U/
executeUpdate(); ]H4T80wm&
} 0~5'O[NhF
else{ < c}cgD4
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); v&NC` dVR
} P sLMV:O9S
} mrzrQ@sN
} v~2$9x!9
//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 RiY9[ec2
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类写好了,下面是在JSP中如下调用。 o6PDCaT7
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<% 8d90B9
CountBean cb=new CountBean(); ?5A!/`E&%
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ,&1DKx
CountCache.add(cb); d&dp#)._8
out.print(CountCache.list.size()+"<br>"); /"Bm1
CountControl c=new CountControl(); j}2,|9ne
c.run(); ~ "^]\3#
out.print(CountCache.list.size()+"<br>"); 5f:Mb|.?
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