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: (9bU\4F\
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CountBean.java lBn<\Y!^
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/* e_Zs4\^ef
* CountData.java C&F%
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* [YQtX_;w
* Created on 2007年1月1日, 下午4:44 oCwep^P(v
* ;E}&{w/My
* To change this template, choose Tools | Options and locate the template under "-fyX!
* the Source Creation and Management node. Right-click the template and choose &=zJ MGa
* Open. You can then make changes to the template in the Source Editor. gISA13
*/ SFzoRI=qG
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package com.tot.count; uUl ;}W
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/** R||$Wi[$
* [L7S`Z
* @author b`wT*&
*/ 2!f'l'}
public class CountBean { B8cg[;e81
private String countType; qPN
int countId; GDj_+G;tO\
/** Creates a new instance of CountData */ ?,v@H$)3_
public CountBean() {} wPyc?:|KD?
public void setCountType(String countTypes){ ;J?fK69%
this.countType=countTypes; ^=I[uX-3ue
} sS)tSt{C
public void setCountId(int countIds){ zv1,DnkqF
this.countId=countIds; kPEU }Kv
} +Kmxo4p
public String getCountType(){ 3F6'3NvVc2
return countType; F0m[ls$
} Vg(p_k45`
public int getCountId(){ |rpMwkR
return countId; 9(&$Gwi
} ,g P;XRe1
} z:n
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CountCache.java 4/o9K*M+
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/* p<VW;1bt5
* CountCache.java 4J[bh
* Z\-Gr
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* Created on 2007年1月1日, 下午5:01 7|m{hSc
* 8Z@O%\1x6
* To change this template, choose Tools | Options and locate the template under X7aj/:fXe
* the Source Creation and Management node. Right-click the template and choose hO3C _}
* Open. You can then make changes to the template in the Source Editor. Y5>'(A>
*/ LQ$dT#z2A
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package com.tot.count; OOsd*nX/
import java.util.*; 3e[k 9`
/** [xs`Pi
* d[(%5pw~zL
* @author I7ySm12}
*/ Erl@]P4
public class CountCache { or`"{wop
public static LinkedList list=new LinkedList(); @[(%b{TE;
/** Creates a new instance of CountCache */ :Ea]baM"
public CountCache() {} wZ8LY;
public static void add(CountBean cb){ `Q^Vm3h
if(cb!=null){ B@3>_};Ct
list.add(cb); BW)t2kR&
} zHj_q%A
} Z}O0DfT;
} V[|k:($
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CountControl.java lce~6}
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/* ^q~.5c|
* CountThread.java (7aE!r\Ab
* Bq:: 5,v
* Created on 2007年1月1日, 下午4:57 [h
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* I'cM\^/h
* To change this template, choose Tools | Options and locate the template under
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* the Source Creation and Management node. Right-click the template and choose HQ|{!P\/?U
* Open. You can then make changes to the template in the Source Editor. TLzcQ |
*/ m+'X8}GC#O
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package com.tot.count; PDh1*bf{u
import tot.db.DBUtils; wa9{Q}wSa
import java.sql.*; )&elr,b/y
/** Boa?Ghg
* 20uR? /|@
* @author *r3u=oWb
*/ hmd, g>J:<
public class CountControl{ T\HP5&
private static long lastExecuteTime=0;//上次更新时间 X"G3lG
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 y+[wlo&WC
/** Creates a new instance of CountThread */ Yc'7F7.<6
public CountControl() {} YI?y_S
public synchronized void executeUpdate(){ 2|^bDg;W+u
Connection conn=null; ].w$b)G
PreparedStatement ps=null; 65A>p:OO
try{ e.g$|C^$m
conn = DBUtils.getConnection(); z//6yr
conn.setAutoCommit(false); P(r}<SM
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 80M4~'3
for(int i=0;i<CountCache.list.size();i++){ `S7${0e
CountBean cb=(CountBean)CountCache.list.getFirst(); ?+#E&F
CountCache.list.removeFirst(); >7V&pH'
ps.setInt(1, cb.getCountId()); M*c`@\
ps.executeUpdate();⑴ CD0SXNi"zH
//ps.addBatch();⑵ .!t'&eV
} k4-C*Gx$h
//int [] counts = ps.executeBatch();⑶ ZjJEjw
conn.commit(); T+/Gz'
}catch(Exception e){ Wm ?RB0
e.printStackTrace(); BPKeG0F7
} finally{ U`"nX)$
try{ Ih95&HsdC
if(ps!=null) { c~Hq.K$d
ps.clearParameters(); Icf@uQ6
ps.close(); _zO,VL
ps=null; t
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} }%rz"kB
}catch(SQLException e){} P8s'e_t
DBUtils.closeConnection(conn); h^0!I TL ^
} 0)qLW&
w
} vi>V6IC4v
public long getLast(){ dDk<J;~jGJ
return lastExecuteTime; Lp/]iZ@
} \G*vY#]
public void run(){ (sn|`k3I
long now = System.currentTimeMillis(); 7[V'3
if ((now - lastExecuteTime) > executeSep) { `ml;#n,*
//System.out.print("lastExecuteTime:"+lastExecuteTime); O@_)]z?jUc
//System.out.print(" now:"+now+"\n"); sOW-GWSE<
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); #PmF@
CHR
lastExecuteTime=now; 2{h9a0b
executeUpdate(); z|yC [Ota
} AuU:613]W8
else{ Tr}c]IP*
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); *$_<|
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} VG\ER}s&P
} 6i\b&
} XH2g:$
//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 GL1!Z3
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类写好了,下面是在JSP中如下调用。 femAVx}go
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<% Fk
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CountBean cb=new CountBean(); TaB35glLY
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); =RUKN38
CountCache.add(cb); 0:nQGX!N
out.print(CountCache.list.size()+"<br>"); t9x.O
CountControl c=new CountControl(); *4[3?~_B#6
c.run(); ]}G(@9
out.print(CountCache.list.size()+"<br>"); }EOn=*
%>