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: P$Q,t2$A
|DYgc$2pN
CountBean.java vi28u xc
Y#QXvo%
/* hn~btu9h
* CountData.java WLA&K]
* %JgdLnQE
* Created on 2007年1月1日, 下午4:44 )"Z6Q5k^
* 8@Bm2?$}g
* To change this template, choose Tools | Options and locate the template under 1'N<ITb
* the Source Creation and Management node. Right-click the template and choose EJ(36h
* Open. You can then make changes to the template in the Source Editor. {Fqwr>e
*/ K|Eelhm
3"juj'
package com.tot.count; ZZ L@UO>:
<<b]v I
/** N<ux4tz
* S*gm[ZLQ
* @author YmpaLZJ
*/ OAD W;fj
public class CountBean { {,u})U2
private String countType; ,,!P-kK$
int countId; p8 Ao{
/** Creates a new instance of CountData */ U>OAtiq JX
public CountBean() {} g/_0WW] }
public void setCountType(String countTypes){ *AP"[W
this.countType=countTypes; 8t. QFze?
} T@*'}*
public void setCountId(int countIds){ t|mK5aR4
this.countId=countIds; #4JLWg
} 8d2\H*a9~
public String getCountType(){ "}wO<O6[
return countType; KyyVO"
} ;b:'i&r
public int getCountId(){ \A,zwdt
P
return countId; jJ-C\
v
} ];lZ:gT
} T2/:C7zL
- U\'Emu4
CountCache.java #]6{>n1*+w
T=)qD2?
/* E3l*_b0
* CountCache.java 1.+6x4%rV
* ;-XfbqZ\
* Created on 2007年1月1日, 下午5:01 |35OA/O?X
* K,I
* To change this template, choose Tools | Options and locate the template under dJ
m9''T')
* the Source Creation and Management node. Right-click the template and choose \hZ%NLj
* Open. You can then make changes to the template in the Source Editor. KbtV>
*/ }{VOy PG
\ ZE[7Ae
package com.tot.count; PkI+z_
import java.util.*; /.<v,CR
/** 5QLK
* 9$Z0mz k
* @author >Rd~-w)!|
*/ )S(Ly.
public class CountCache { pm ,xGo2
public static LinkedList list=new LinkedList(); |5tZ*$nGa
/** Creates a new instance of CountCache */ <JH,B91
public CountCache() {} XWnP(C9?
public static void add(CountBean cb){ N{S) b
if(cb!=null){ Jp_#pV*}:
list.add(cb); O"+0 b|
} No} U[u.O
} 5N;'CAk
} *
l1*zaE
M|K^u.4
CountControl.java #aU!f"SS
U:C:ugm
/* 6<<"9mxK
* CountThread.java 5EcVW|(
* j*G: 8Lg
* Created on 2007年1月1日, 下午4:57 H{vKk
* $VvgzjrH
* To change this template, choose Tools | Options and locate the template under 1.F&gP)9
* the Source Creation and Management node. Right-click the template and choose !T][c~l
* Open. You can then make changes to the template in the Source Editor. p8_^6wfg
*/ xBVOIc[4(
JEp)8{.bW8
package com.tot.count; @m9pb+=v
import tot.db.DBUtils; hOUH1m.
import java.sql.*; >ep<W<b
/** eKvr1m- -
* gCb+hQq\
* @author <.QaOLD
*/ &,k!,<IF
public class CountControl{ vTO9XHc E
private static long lastExecuteTime=0;//上次更新时间 8m?(* [[
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 )N&SrzqTK
/** Creates a new instance of CountThread */ |(3y09
public CountControl() {} Yt]`>C[|D
public synchronized void executeUpdate(){ #dWz,e3
Connection conn=null; @%Ld\8vdfJ
PreparedStatement ps=null; p2Ep(0w,R5
try{ THp_ dTD
conn = DBUtils.getConnection(); n[iwi
conn.setAutoCommit(false); 0\tac/
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 2{rWAPHgz
for(int i=0;i<CountCache.list.size();i++){ {5E8eQ
CountBean cb=(CountBean)CountCache.list.getFirst(); @|anu&Hm
CountCache.list.removeFirst(); j%Au0k
ps.setInt(1, cb.getCountId()); <eG| `
ps.executeUpdate();⑴ $*#^C;7O
//ps.addBatch();⑵ Sv n7.Ivep
} |q*yuK/
//int [] counts = ps.executeBatch();⑶ L1SKOM$
conn.commit(); .KA-=$~J1
}catch(Exception e){ >zW2w2O3
e.printStackTrace(); =6[.||9
} finally{ u?Ffqt9'
try{ ?s^qWA
if(ps!=null) { )j36Y =r3
ps.clearParameters(); ,<rC,4-F<
ps.close(); h+Co:pr
ps=null; *#Cx-J
} oe|#!SM(
}catch(SQLException e){} `q*[fd1u.
DBUtils.closeConnection(conn); =OHX5:Z
} 5~[7|Y
} _nMd
public long getLast(){ I@cw=_EQL
return lastExecuteTime; .uJ
J<
} D;pI!S<#
public void run(){ <a6pjx>y
long now = System.currentTimeMillis(); 6nW)2LV
if ((now - lastExecuteTime) > executeSep) { PlkZ)S7C
//System.out.print("lastExecuteTime:"+lastExecuteTime); loVg{N:
//System.out.print(" now:"+now+"\n"); Fc5.?X-
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); X,k^p[Rcu
lastExecuteTime=now; $gUlM+sK
executeUpdate(); |H?t+Dyn)q
} _Vr- bpAf
else{ + `|A/w
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); s:3[#&PQpN
} o9eOp3w30
} [I
*_0
} |(>`qL{|
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 QoZV6
*:n~j9V-
类写好了,下面是在JSP中如下调用。 }(nT(9|
EK';\}
<% Nm?^cR5r
CountBean cb=new CountBean(); dR S:S_
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); |4df)
CountCache.add(cb); xb,d,(^ ]R
out.print(CountCache.list.size()+"<br>"); )^ah, ;(
CountControl c=new CountControl(); [CJ<$R !
c.run(); ^K?-+
out.print(CountCache.list.size()+"<br>"); d?fS#Ryb
%>