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: N&M~0iw
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CountBean.java `P9XqWr
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/* f/V
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* CountData.java 7P9=)$(EH
* ldp%{"ZZ
* Created on 2007年1月1日, 下午4:44 L@gWzC~?Q
* LU9A#
* To change this template, choose Tools | Options and locate the template under "70WUx(\t
* the Source Creation and Management node. Right-click the template and choose G8;w{-{m
* Open. You can then make changes to the template in the Source Editor. S*n@81Z
*/ *f?4
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package com.tot.count; R~ZFy0
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/** KhMSL
* _N@ro
* @author 2"B _At
*/ nH<eR)0
public class CountBean { 'z[Sp~I\
private String countType; SGe^ogO"v
int countId; 3Oi
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/** Creates a new instance of CountData */ VhNz8)
public CountBean() {} Iyyh!MVF
public void setCountType(String countTypes){ EbdfV-E
this.countType=countTypes; TsGE cxIg
} 3%E74 mOcD
public void setCountId(int countIds){ (x3.poSt
this.countId=countIds; pbU!dOU~e
} Q*b]_0Rb
public String getCountType(){ w.0qp)}
return countType; <^lRUw
} -k"^o!p
public int getCountId(){ }|XtypbL
return countId; Q^#;WASi
} u5Ftu?t
} V?=8".GiX
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CountCache.java ETXZ?\<a5
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/* |0%+wB
* CountCache.java v_nj$1dY6
* V7Mh-]
* Created on 2007年1月1日, 下午5:01 iySRY^
* >mjNmh7
* To change this template, choose Tools | Options and locate the template under YxP@!U9dE,
* the Source Creation and Management node. Right-click the template and choose
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* Open. You can then make changes to the template in the Source Editor. 7=DjI ~
*/ Yk5}`d!:
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package com.tot.count; n;:rf 7hGY
import java.util.*; )kkhJI*v
/** R@`y>X GNJ
* .Fa4shNV
* @author ZAXN6h
*/ 2!$gyu6bpG
public class CountCache { yd?x=|
public static LinkedList list=new LinkedList(); #jxe%2'Ot
/** Creates a new instance of CountCache */ q2et|QCru
public CountCache() {} 4- [J@
public static void add(CountBean cb){ I:d[Q
s
if(cb!=null){ :=[XW?L%x
list.add(cb); n8DxB@DI
} KFFSv{m[
} ?IGVErnJJC
} [NTtz
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CountControl.java &Ky_v^
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/* 14"J d\M8
* CountThread.java hc'-Dh
* %Pqf{*d8
* Created on 2007年1月1日, 下午4:57 |H!9fZO
* #2EI\E&$
* To change this template, choose Tools | Options and locate the template under _z1(y}u}
* the Source Creation and Management node. Right-click the template and choose {Pc<u
gfl
* Open. You can then make changes to the template in the Source Editor. 6l4mS~/
*/ ]| +<P-
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package com.tot.count; qvv2O1c"A
import tot.db.DBUtils; ;j)FnY=: -
import java.sql.*; ?2g`8[">
/** HO''&hz
* [l8jRT=R
* @author 3hK#'."`N
*/ wW/7F;54
public class CountControl{ P:N1#|g
private static long lastExecuteTime=0;//上次更新时间 0s>/mh;
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 |a#f\
/** Creates a new instance of CountThread */ ;Yg{zhJX~
public CountControl() {} -^ C=]Medl
public synchronized void executeUpdate(){ <!pvqNApg
Connection conn=null; <bD>m[8,
PreparedStatement ps=null; EVNY*&p
try{ L^{|uP15N
conn = DBUtils.getConnection(); PtTH PAKj
conn.setAutoCommit(false); 5=1^T@~#&
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); D2,z)O%VK
for(int i=0;i<CountCache.list.size();i++){ wWp(yvz
CountBean cb=(CountBean)CountCache.list.getFirst(); [u._q:A
CountCache.list.removeFirst(); u@4V7;L
ps.setInt(1, cb.getCountId()); P(K>=O
ps.executeUpdate();⑴ MXyaE~LK
//ps.addBatch();⑵ hsw9(D>jp
} e A}%C.ZR
//int [] counts = ps.executeBatch();⑶ O1`9Y}G(r
conn.commit(); ?Sb8@S&J
}catch(Exception e){ "hdvHUz
e.printStackTrace(); ~wVd$%7`
} finally{ 9,^_<O@Q
try{ Y!T
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if(ps!=null) { }YHX-e<Yx]
ps.clearParameters(); FEJ~k1z
ps.close(); EMc;^ d
ps=null; DK
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}
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}catch(SQLException e){} +Lnsr\BA
DBUtils.closeConnection(conn); ku..aG`
} D91e\|]
} 3q?\r`
a
public long getLast(){ T]?n)L,2
return lastExecuteTime; "hy.GWF|*
} 0pSmj2/,.
public void run(){ @GvztVYo
long now = System.currentTimeMillis(); Z*FrB58
if ((now - lastExecuteTime) > executeSep) { K_ci_g":
//System.out.print("lastExecuteTime:"+lastExecuteTime); C*G=cs\i
//System.out.print(" now:"+now+"\n"); D3x /OyG(
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); q@jq0D)g
lastExecuteTime=now; k`x=D5s\
executeUpdate(); YOJ6w
} }`NU@O#
else{ kVD(Q~<
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); %G?;!Lz
} ;q1A*f\:#
} {Ions~cO)
} T_lsGu/
//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 ymNnkFv
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类写好了,下面是在JSP中如下调用。 zR32PG>9
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<% h)me\U7UC
CountBean cb=new CountBean(); 7^Yk`Z?|a
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); wm+})SOX9
CountCache.add(cb); Rtjqx6-B;
out.print(CountCache.list.size()+"<br>"); E[^ {w
CountControl c=new CountControl(); M1%Dg'}G
c.run(); _A0mxq
out.print(CountCache.list.size()+"<br>"); J=dJsk
%>