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: Sr+1.77}
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CountBean.java aPb!-o{
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/* %##9.Xm6l
* CountData.java )7`~U"r
* 7olA@;$
* Created on 2007年1月1日, 下午4:44 92tb`'
* dl;A'/(t
* To change this template, choose Tools | Options and locate the template under C3<3
* the Source Creation and Management node. Right-click the template and choose
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* Open. You can then make changes to the template in the Source Editor. hOC,Eo
*/ tllg$CQ5
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package com.tot.count; }`g*pp*
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/** 9q5[W=|
* 4{Ak|
* @author ]E3g8?L
*/ ~G$OY9UC
public class CountBean { 7yj2we
private String countType; #nxx\,i>
int countId; i@;a%$5
/** Creates a new instance of CountData */ [&4y@
public CountBean() {} >L(F{c:
public void setCountType(String countTypes){ FG(`&S+,
this.countType=countTypes; <;T7qEIlo
} G?g7G,|d
public void setCountId(int countIds){ EtcamI*`
this.countId=countIds; Q6>vF)(
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} FPMk&
public String getCountType(){ [/kO>
return countType; (Zn\S*_@/
} t2gjhn^p
public int getCountId(){ WT)")0)[
return countId; /6fPC;l
} !K2[S
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} yUG5'<lX
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CountCache.java ?|/}~nj7
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/* |)_R
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* CountCache.java ~_&.A* Jh
* +OmSR*fA0
* Created on 2007年1月1日, 下午5:01 .s?OKy
* 5zGj,y>u
* To change this template, choose Tools | Options and locate the template under :}z%N7T
* the Source Creation and Management node. Right-click the template and choose d7P @_jO6
* Open. You can then make changes to the template in the Source Editor. Yp)U'8{h c
*/ +g[B &A!d+
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package com.tot.count; MD)"r>k
import java.util.*; ^&.?kJM
/** O /&%`&2
* cn0Fz"d
* @author H-W)Tq_?-
*/ 8iN As#s
public class CountCache { z,)sS<t(
public static LinkedList list=new LinkedList(); 6~S0t1/t?
/** Creates a new instance of CountCache */ c
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public CountCache() {} NjxW A&[ng
public static void add(CountBean cb){ pYG,5+g
if(cb!=null){ lo: ~~l
list.add(cb); a:}"\>Aj
} B>ZPn6?y
} C":\L>Ax
} zTB9GrU
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CountControl.java l,FoK76G
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/* (do=o&9pm
* CountThread.java ~P_kr'o
* D8Rmxq!
* Created on 2007年1月1日, 下午4:57 uN
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* [{F7Pc
* To change this template, choose Tools | Options and locate the template under '.yWL
* the Source Creation and Management node. Right-click the template and choose sV[Z|$&Z
* Open. You can then make changes to the template in the Source Editor. HW726K*
*/ 2hJ3m+N^
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package com.tot.count; }!V<"d,!
import tot.db.DBUtils; [Z\1"m
import java.sql.*; ->I{
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/** 5R `6zhf
* *hs<Ez.cC
* @author X.l"f'`l
*/ PV6*-[
public class CountControl{ /'6[*]IZP
private static long lastExecuteTime=0;//上次更新时间 i%PHYSJ.
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ddDJXk)!0
/** Creates a new instance of CountThread */ -_DiD^UcXn
public CountControl() {} 0DIM]PS
public synchronized void executeUpdate(){ Q 02??W
Connection conn=null; J 7;n;Mx
PreparedStatement ps=null; y~c[sW
try{ zl
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conn = DBUtils.getConnection(); MZW
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conn.setAutoCommit(false); OCO,-(
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); F>kn:I"X)
for(int i=0;i<CountCache.list.size();i++){ ,
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CountBean cb=(CountBean)CountCache.list.getFirst(); jQeE07g
CountCache.list.removeFirst(); ;To+,`?E;q
ps.setInt(1, cb.getCountId()); N vHy'
ps.executeUpdate();⑴ vKf;&`^qE
//ps.addBatch();⑵ #'Y6UGJ\n
} ZX6=D>)u
//int [] counts = ps.executeBatch();⑶ JvJ!\6Q@
conn.commit(); `[ ` *@O(y
}catch(Exception e){ k>;r9^D
e.printStackTrace(); S%s|P=u
} finally{ pD_eo6xX
try{ rn[}{1I33Q
if(ps!=null) { 2]RH)W86;
ps.clearParameters(); us,,W(q
ps.close(); _B7?C:8Q-
ps=null; d>b,aj(
} i
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}catch(SQLException e){} FlA\Ad;v
DBUtils.closeConnection(conn); y#Za|nt
} 2N8sq(LK{
} f+aS2k(e>
public long getLast(){ ,iv%^C",)
return lastExecuteTime; 9Bvn>+_K
} p9 ,\ {Is
public void run(){ {9|$%4kRl
long now = System.currentTimeMillis(); dYew7
if ((now - lastExecuteTime) > executeSep) { ]7R&m)16
//System.out.print("lastExecuteTime:"+lastExecuteTime); a2=uM}Hsp
//System.out.print(" now:"+now+"\n"); O$umu_
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); i_'R"ob{S
lastExecuteTime=now; c>WpO Z,
executeUpdate(); GKsL~;8"
} sHPwW5j/o'
else{ >5~Zr$
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); W
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} 6[3Ioh
} CMxjX
} V.QzMF"o
//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 Dss/>!
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类写好了,下面是在JSP中如下调用。 o
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<% 7ru9dg1?
CountBean cb=new CountBean(); <;,S"e
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); q{De&Bu
CountCache.add(cb); ^2;(2s
out.print(CountCache.list.size()+"<br>"); g"dZB2`C
CountControl c=new CountControl(); Q!2iOvK
c.run(); 0q>NE<L
out.print(CountCache.list.size()+"<br>"); C>`.J_N
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