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: B 2ec@]uD`
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CountBean.java ?mlNL/:
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/* -1J[n0O.
* CountData.java + T8B:
* uw2hMt (N
* Created on 2007年1月1日, 下午4:44 D.mHIsX6\
* /JT#^Y
* To change this template, choose Tools | Options and locate the template under >a}f{\Q
* the Source Creation and Management node. Right-click the template and choose @/k@WhFZ
* Open. You can then make changes to the template in the Source Editor. 5ms""LD/
*/ S%`0'lzzj
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package com.tot.count; XQS9,Hl
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/** be +4junf
* +a*tO@HG
* @author "Y\_TtY
*/ #UbF9})q
public class CountBean { cH>%r^G\
private String countType; l<N}!lG|
int countId; ."FuwKSJCo
/** Creates a new instance of CountData */ `hb%+-lj+
public CountBean() {} D::rGB?.b
public void setCountType(String countTypes){ G\(|N9^:
this.countType=countTypes; 8(* [Fe9
} +!|9hF'
public void setCountId(int countIds){ NQ6sGL
this.countId=countIds; |DsnNk0c
} xt*u4%
public String getCountType(){ ~*wk6&|
return countType; {D=@n4JO
} f;b[w
public int getCountId(){ ,N0#!<}4
return countId; /i77
} #f+$Ddg*
} g1(IR)U!z
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CountCache.java [KxF'm z9
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/* S9#)A->
* CountCache.java h2D>;k
* %VnbmoO
* Created on 2007年1月1日, 下午5:01
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* /bVoErf
* 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 0L/n ?bf
* Open. You can then make changes to the template in the Source Editor. CvD"sHVq%
*/ iTQD
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package com.tot.count; eow'K
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import java.util.*; )vSRHE
/** 5D'\b}*lJ}
* [W7CXZDd
* @author d m`E!R_
*/ 9th,VnD0
public class CountCache { r
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public static LinkedList list=new LinkedList(); gN"7be&J
/** Creates a new instance of CountCache */ .p(T^ m2A*
public CountCache() {} is-7
j7;
public static void add(CountBean cb){ *I0T{~
if(cb!=null){ y_?Me]
list.add(cb); z5YWt*nm
} -jiG7OL
} OtNd,U.dE
} 1 9CK+;b
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CountControl.java X)% A6M
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/* >j QWn@
* CountThread.java J7g8D{4
* v'3J.?N
* Created on 2007年1月1日, 下午4:57 .yEBOMNZ
* 7yh/BZ1
* To change this template, choose Tools | Options and locate the template under aSnFKB
* the Source Creation and Management node. Right-click the template and choose eYvWZJa4
* Open. You can then make changes to the template in the Source Editor. 55fC~J<
*/ ^=-y%kp"
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package com.tot.count; K9up:.{QQ
import tot.db.DBUtils; Qr{E[6
import java.sql.*; @nCd
/** +csi[c)3E
* #%h-[/
* @author h3xAJ!
*/ *vwbgJG! *
public class CountControl{ 73\JwOn~
private static long lastExecuteTime=0;//上次更新时间 &eX!#nQ_.
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 |Ur"&
Z{
/** Creates a new instance of CountThread */ {fjdr
public CountControl() {} BNs@n"k
public synchronized void executeUpdate(){ V6,H}k
Connection conn=null; fd.^h*'mU
PreparedStatement ps=null; ]%u@TK7
try{ K42K!8$
conn = DBUtils.getConnection(); @W"KVPd
conn.setAutoCommit(false); z+n,uHs
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Jh!I:;/
for(int i=0;i<CountCache.list.size();i++){ )`(p9@,V
CountBean cb=(CountBean)CountCache.list.getFirst(); #$8% w
CountCache.list.removeFirst(); ",KCCis
ps.setInt(1, cb.getCountId()); $cU!m(SILQ
ps.executeUpdate();⑴ $arK(
//ps.addBatch();⑵ YF>m$?;
} %#xaA'?
[
//int [] counts = ps.executeBatch();⑶ 2$ze=
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conn.commit(); 85Otss/mM
}catch(Exception e){ o9dY9o+Z
e.printStackTrace(); 4?q<e*W
} finally{ ?b>,9A.Z
try{ IHv[v*4:
if(ps!=null) { 9^#c|
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ps.clearParameters(); 7%|~>
ps.close(); 6"&6`f
ps=null; "ozr+:#\
} t^G"f;Ra+
}catch(SQLException e){} cmU1!2.1E
DBUtils.closeConnection(conn); 1oWED*B
} heC/\@B
} $m-2HhqZ
public long getLast(){ (Hb:?(
return lastExecuteTime; 4i(JZN?
} UKT%13CO4U
public void run(){ FW G6uKv
long now = System.currentTimeMillis(); oF1,QQ^dg
if ((now - lastExecuteTime) > executeSep) { D!Pq4'd(
//System.out.print("lastExecuteTime:"+lastExecuteTime); 0vD7v
//System.out.print(" now:"+now+"\n"); S]Mw#O|
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ]rH\`0
lastExecuteTime=now; MS
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executeUpdate(); 8h*Icf
} 'R'*kxf
else{ L"1}V
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); /)}q Xx&
} ($; 77fPR
} `-J%pEIza
} ZJzt~
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//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 afuOeZP
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类写好了,下面是在JSP中如下调用。 'mFqEn
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<% pS'FI@.'{
CountBean cb=new CountBean(); 1q:2\d]
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); jZ~n[
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CountCache.add(cb); 2q=AEv/
out.print(CountCache.list.size()+"<br>"); PGhY>$q>b
CountControl c=new CountControl(); ~5%W:qwQ
c.run(); xqG[~)~
out.print(CountCache.list.size()+"<br>"); *U,@q4
%>