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: X?>S24I"9
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CountBean.java e6sL N
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/* bRNE:))r_
* CountData.java ><\mt
* ]P(Eo|)m
* Created on 2007年1月1日, 下午4:44 4LBjqv,P
* BqR;d
* To change this template, choose Tools | Options and locate the template under l,6="5t
* the Source Creation and Management node. Right-click the template and choose 1)u=&t,
* Open. You can then make changes to the template in the Source Editor. )/
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*/ r+m8#uR
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package com.tot.count; VrF]X#\)
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/** He#+zE;
* ;-*4 (3lu
* @author JFYeOmR+l
*/ akd~Z
public class CountBean { $|(roC(
private String countType; @|-ydm0
int countId; ^o,@9GTs
/** Creates a new instance of CountData */ 1O(fI|gcO
public CountBean() {} }[ AIE[
public void setCountType(String countTypes){ R0. `2=
this.countType=countTypes; XHN?pVZ7
} R#1m_6I
public void setCountId(int countIds){ kZz;l(?0
this.countId=countIds; i"JF~6c<
} c?q#?K
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public String getCountType(){ ]~ec]Y
return countType; ?)]sfJG
} '?3Hy|}
public int getCountId(){
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return countId; *:\QD 8 ^
} !29
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} = @3Qsd
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CountCache.java AqN(htGvx
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/* w?Q@"^IL
* CountCache.java IDLA-Vxo
* c
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* Created on 2007年1月1日, 下午5:01 OmU.9PDg-
* ;yHA.}
* To change this template, choose Tools | Options and locate the template under CuuHRvU8
* the Source Creation and Management node. Right-click the template and choose <&H.pN1_
* Open. You can then make changes to the template in the Source Editor. :M=!MgD3w
*/ `uzRHbJ`
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package com.tot.count; .@B\&U7
import java.util.*; {jk {K6 }
/** [;|g2\
* <~:
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* @author _^SNI ~
*/ l8^^ O
public class CountCache { Q8\Ks|u]
public static LinkedList list=new LinkedList(); |nm,5gPNC
/** Creates a new instance of CountCache */ Yq1 ~"he8
public CountCache() {} zlSwKd(
public static void add(CountBean cb){ X_%78$N-a`
if(cb!=null){ ;K:.*sAa
list.add(cb); P_b00",S
} g1&GX(4[
} {?5EOp~
} ,{E'k+
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CountControl.java pdtK3Pf
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/* q=96Ci _a
* CountThread.java C}+(L3Z
* w7dG=a&
* Created on 2007年1月1日, 下午4:57 ia?8Z"&lK
* `^_.E:f
* To change this template, choose Tools | Options and locate the template under A;2?!i#f
* the Source Creation and Management node. Right-click the template and choose F}sfk}rp
* Open. You can then make changes to the template in the Source Editor. r-'j#|^tz
*/ R \`,Q'3
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package com.tot.count; :j9;P7&"?
import tot.db.DBUtils; [=LQ,e$r7
import java.sql.*; *B3` #t
/** \J1Jn~
* [8)Zhw$
* @author DM>j@(uWF
*/ Xq J@NgsY
public class CountControl{ :k(aH Ua
private static long lastExecuteTime=0;//上次更新时间 ["@K~my~D*
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 T[<9Ty'^
/** Creates a new instance of CountThread */ "G4{;!0C
public CountControl() {} C9bf1ddCW&
public synchronized void executeUpdate(){ Gc
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Connection conn=null; o ue;$8
PreparedStatement ps=null; I.(/j
try{ h?$4\^/
conn = DBUtils.getConnection(); uV%7|/fD
conn.setAutoCommit(false); noL<pkks~R
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); bNc=}^
for(int i=0;i<CountCache.list.size();i++){ I^lb;3uR
CountBean cb=(CountBean)CountCache.list.getFirst(); U)c,ZxE
CountCache.list.removeFirst(); ql8CgL
ps.setInt(1, cb.getCountId()); ZEApE+m
ps.executeUpdate();⑴ ?[VS0IBS
//ps.addBatch();⑵ t,=khZ
} u1>| 2D
//int [] counts = ps.executeBatch();⑶ E@[`y:P
conn.commit(); eb+[=nmP
}catch(Exception e){ a2p<HW;)m
e.printStackTrace(); (wbG0lu
} finally{ 81aY*\
try{ ^Z}INUv]7
if(ps!=null) { iL5+Uf)E3
ps.clearParameters(); seq
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ps.close(); nk6xavQji
ps=null; WH'[~O
} Iy`Zh@"~
}catch(SQLException e){} r0S"}<8O
DBUtils.closeConnection(conn); =\_MJ?A$
} iyj&O"
} xT=|Uc0
public long getLast(){ 2Uk$9s
return lastExecuteTime; 0~^opNR
} e
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public void run(){ FtY*I&
long now = System.currentTimeMillis(); zXMIDrq
if ((now - lastExecuteTime) > executeSep) { tJg
//System.out.print("lastExecuteTime:"+lastExecuteTime); {mueP6Gz@J
//System.out.print(" now:"+now+"\n"); :Fm+X[n
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); }vcC4 =t/
lastExecuteTime=now; Yo:>m*31
executeUpdate(); sFB; /*C
} \.Q"fd?a_D
else{ ,=z8aiUu
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ^V>sNR
} [h,T.zpa
} [l'~>
} t5e% "}>7H
//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 v>0xHQD*<M
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类写好了,下面是在JSP中如下调用。 ~f){`ZJc
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<% cH"M8gP#
CountBean cb=new CountBean(); SOeL@!_
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); *gZ4Ub|O
CountCache.add(cb); qTiX;e\W
out.print(CountCache.list.size()+"<br>"); _X;5ORH"
CountControl c=new CountControl();
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c.run(); ^=Up UB
out.print(CountCache.list.size()+"<br>"); {v~&.|
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