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: AC
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CountBean.java )!g{Sbl
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/* d!KsNkk
* CountData.java -",=G\XZ
* 1h*)@
* Created on 2007年1月1日, 下午4:44 LG~S8u
* c PgfTT
* To change this template, choose Tools | Options and locate the template under <<D$+@wxm
* the Source Creation and Management node. Right-click the template and choose h8\
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* Open. You can then make changes to the template in the Source Editor. yCJ Fo
*/ v7%X@j]ji
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package com.tot.count; $?,a[79
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/** nR4y`oP+
* Xtwun
* @author 5XuT={o
*/ ^QuiH'
public class CountBean {
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private String countType; o!:8nXw
int countId; \4"S7.% |
/** Creates a new instance of CountData */ _U;eN|Ww
public CountBean() {} USN8N (
public void setCountType(String countTypes){ "Jjs"7
this.countType=countTypes; :'aAZegQY
} Soie^$
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public void setCountId(int countIds){ p3/*fH98
this.countId=countIds; /7!""{1\\
} d:G]1k;z
public String getCountType(){ GE>[*zN
return countType; \rykBxs
} \A`hj~
public int getCountId(){ G/%iu;7ZCb
return countId; mDh1>>K'~
} 'qdPw%d
} =)O,`.M.Y
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CountCache.java B2Xn?i3 l
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/* {cpEaOyOM
* CountCache.java X-Wz:NA
* )otb>w5
* Created on 2007年1月1日, 下午5:01 Y!6/[<r$~k
* *5<Sr q'
* To change this template, choose Tools | Options and locate the template under ,@m@S^
* the Source Creation and Management node. Right-click the template and choose <o2r~E0r3
* Open. You can then make changes to the template in the Source Editor. fF*`'i=!
*/ VF&Z%O3n
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package com.tot.count; iqnJ~g
import java.util.*; 2iu_pjj
/** ,]}?.g
* KYJjwXT28W
* @author -C#PQV
*/ 8@NH%zWBp
public class CountCache { `V[!@b:
public static LinkedList list=new LinkedList(); "m{,~'x
/** Creates a new instance of CountCache */ P,ua<B}L
public CountCache() {} A?TBtAe
public static void add(CountBean cb){ t>B^q3\q?
if(cb!=null){ XWJwJ
list.add(cb); 6 \B0^
} mj?16\|]
} ~lEVXea!
} +l^LlqA
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CountControl.java }AZc8o-
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/* /S:F)MO9
* CountThread.java (h']a!
* k7tYa;C
* Created on 2007年1月1日, 下午4:57 61U<5:#l
* PiFD^w
* To change this template, choose Tools | Options and locate the template under hVjNZ
* the Source Creation and Management node. Right-click the template and choose ~f|Z%&l|
* Open. You can then make changes to the template in the Source Editor. D .vw8H3
*/ lq.Te,Y%w
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package com.tot.count; %iJ%{{f`
import tot.db.DBUtils; P)dL?vkK
import java.sql.*; [6jbgW~E
/** Qy#)Gxp
* 9*6]&:fm
* @author }U@m*dEG
*/ Li 2Zndp
public class CountControl{ # N~,F@t
private static long lastExecuteTime=0;//上次更新时间 BiE08,nj
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ry};m_BY
/** Creates a new instance of CountThread */ DN4#H`
public CountControl() {} 9Pd*z>s
public synchronized void executeUpdate(){ r!}al5~&
Connection conn=null; IB.yU,v
PreparedStatement ps=null; $]aBe
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try{ ^EVc 95|Z
conn = DBUtils.getConnection(); O!D/|.Q#%
conn.setAutoCommit(false); CeT~p6=
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); S)He$B$pp
for(int i=0;i<CountCache.list.size();i++){ o/[
CountBean cb=(CountBean)CountCache.list.getFirst(); !BU)K'mj
CountCache.list.removeFirst(); 3*DXE9gA9
ps.setInt(1, cb.getCountId()); `,wu}F85
ps.executeUpdate();⑴ F{k+7Ftc
//ps.addBatch();⑵ m}VM+=
} ,]R8(bD)
//int [] counts = ps.executeBatch();⑶ E04l|
conn.commit(); 4n
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}catch(Exception e){ _i}wK?n
e.printStackTrace(); Bz8 &R|~>"
} finally{ JU0]Wq <^[
try{ 8OWmzY_=
if(ps!=null) { 8YY|;\F)J~
ps.clearParameters(); mXjgs8s
ps.close(); f<[jwhCWV
ps=null; h~HB0^|
} WoL9V"]
}catch(SQLException e){} Y{Ap80'\6
DBUtils.closeConnection(conn); ed~R>F>
} E|Bd>G
} A,i()R'I
public long getLast(){ {sN"(H4$
return lastExecuteTime; lHBI
} q/@dR{-
public void run(){ p(3sgY1
long now = System.currentTimeMillis(); vg%QXaM
if ((now - lastExecuteTime) > executeSep) { #Olg(:\
//System.out.print("lastExecuteTime:"+lastExecuteTime); `LP!D
//System.out.print(" now:"+now+"\n"); Iur9I>8h
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); O?K./So&
lastExecuteTime=now; $B\E.ml.
executeUpdate(); wuK=6RL
} 8q_0,>w%
else{ J2Et-Cz 1
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Z-Wfcnk
} * UcjQ
} u?Hb(xZtg=
} tFU;SBt8Ki
//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 7s>a2
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类写好了,下面是在JSP中如下调用。 ;i)KHj'
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<% 9{J?HFw*;
CountBean cb=new CountBean(); 0%Q9}l#7
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); IvU{Xm"qB
CountCache.add(cb); ;x[pM_
out.print(CountCache.list.size()+"<br>"); 2ChWe}f
CountControl c=new CountControl(); DnyYMe!r
c.run(); u*R7zY
out.print(CountCache.list.size()+"<br>"); VyZV(k
%>