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: !iO2yp
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CountBean.java w 5 yOSz
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/* b9-IrR4h
* CountData.java X NgcBSD
* i.k7qclL`
* Created on 2007年1月1日, 下午4:44 )fHr]#v
* 8~tX>q<@q
* To change this template, choose Tools | Options and locate the template under U%q-#^A
* the Source Creation and Management node. Right-click the template and choose F+"_]
* Open. You can then make changes to the template in the Source Editor. }}"pQ!Z
*/ GLgf%A`5/_
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package com.tot.count; |lt]9>|
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/** )/?H]o$NU
* d]poUN~x
* @author h5SJVa
*/ q.p.$)
public class CountBean { D/?Ec\t
private String countType; NMe{1RM
int countId; %xN${4)6
/** Creates a new instance of CountData */ W:,Wex^9n
public CountBean() {} ]}dQ~lOE
public void setCountType(String countTypes){ om`T/@_,
this.countType=countTypes; D"rbQXR7$
} V"m S$MN
public void setCountId(int countIds){ &\1n=y
this.countId=countIds; #l ZK_N|1x
} W#S8 2
public String getCountType(){ R*:>h8
return countType; GlnO8cAB
} yVII<ImqIH
public int getCountId(){ +? h}e
return countId; ];Z6=9n
} kk%3 2(By
} CJ*
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CountCache.java $c9-Q+pZ
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/* VGmvfhf#"
* CountCache.java 6|zhqb|s
* 5BJE
* Created on 2007年1月1日, 下午5:01 -~mgct5
* $#q`Y+;L2
* To change this template, choose Tools | Options and locate the template under TWzLJ63*
* the Source Creation and Management node. Right-click the template and choose &)Xc'RQ.C
* Open. You can then make changes to the template in the Source Editor. Lm
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*/ X/yq<_ g
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package com.tot.count; z Fo11;*D
import java.util.*; f<NR6],}
/** |M7cB$y
* P(hGkY=(
* @author X_]rtG
*/ BH">#&j[
public class CountCache { O2?C *
public static LinkedList list=new LinkedList(); 1@DC#2hPr
/** Creates a new instance of CountCache */ 9@lWI
public CountCache() {} ZEAUoC1E1
public static void add(CountBean cb){ JVYH b 60Z
if(cb!=null){ ;f=m+QXU
list.add(cb); <eoie6@3
} |^6{3a
} EU$.{C_O(
} Ks-$:~?5":
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CountControl.java u=
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/* 1z?}'&:
* CountThread.java l4>^79* *
* {'5"i?>s0>
* Created on 2007年1月1日, 下午4:57 O`B,mgT(
* <h/%jM>9/
* To change this template, choose Tools | Options and locate the template under !y= R)k
* the Source Creation and Management node. Right-click the template and choose -QrC>3xZR
* Open. You can then make changes to the template in the Source Editor. V)j[`,M:
*/ ,%M[$S'
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package com.tot.count; [={mCGU
import tot.db.DBUtils; FTf#"'O
import java.sql.*; =l/6-j^
/** #z|Q $
* l3>S{
* @author \84t\jKR
*/ AcC &Q:g
public class CountControl{ yD7BZI
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private static long lastExecuteTime=0;//上次更新时间 ieFl4hh[G
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 o4);5~1l
/** Creates a new instance of CountThread */ 1~5DIU^
public CountControl() {} 0zaK&]oY0
public synchronized void executeUpdate(){ A&Y5z[p
Connection conn=null; T5(S2^)o
PreparedStatement ps=null; iwotEl0*{
try{ Vw;Z0_C
conn = DBUtils.getConnection(); '<R>cN"
conn.setAutoCommit(false); ~HZdIPcC
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); aD^$v
for(int i=0;i<CountCache.list.size();i++){ nHseA
CountBean cb=(CountBean)CountCache.list.getFirst(); 3v/B*M VI
CountCache.list.removeFirst(); OT9]{|7
ps.setInt(1, cb.getCountId()); zLpCKndj
ps.executeUpdate();⑴ K~N$s"Qx
//ps.addBatch();⑵ hH %>
} p+VU:%.t
//int [] counts = ps.executeBatch();⑶ jJy:/!i
conn.commit(); EB~]6.1
}catch(Exception e){ S+ kq1R
e.printStackTrace(); )cqD"> vs
} finally{ CU'JvVe3
try{ l~c[} wv
if(ps!=null) { Zxa.x?:?n
ps.clearParameters(); t`Kbm''d[
ps.close(); [#PE'i4
ps=null;
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} lQn"
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}catch(SQLException e){} U2q6^z4l
DBUtils.closeConnection(conn); I//=C6
} g.lTNQm$u
} WYP ;s7_
public long getLast(){ %6UF%dbYH`
return lastExecuteTime; '![oLy
} *g/klK
public void run(){ !"rPSGK*
long now = System.currentTimeMillis(); xa>| k>I
if ((now - lastExecuteTime) > executeSep) { =>jp\A
//System.out.print("lastExecuteTime:"+lastExecuteTime); J:xGEa t
//System.out.print(" now:"+now+"\n"); B,%Vy!o
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); dY*q[N/pO
lastExecuteTime=now; "mlQ z4D)5
executeUpdate(); kv+%
} sV\_DP/l
else{ C]`uC^6g
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); $Ome]+0
} c8l>OS5i3_
} *FlPGBjJ
} "6B7EH
//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 fz&B$1;8
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类写好了,下面是在JSP中如下调用。 %TB(E<p`
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<% .iXN~*+g
CountBean cb=new CountBean(); R><g\{G]
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 8Zv``t61
CountCache.add(cb); g@.$P>Bh
out.print(CountCache.list.size()+"<br>"); y.r N(
CountControl c=new CountControl(); (eHyas %X
c.run(); @:lM|2:
out.print(CountCache.list.size()+"<br>"); nM,:f)z
%>