Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 e$M \HPc
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 a,3}
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 TQyi-Dc
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 Q%61_l
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分页支持类: [hE0 9W
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java代码: ,C%fA>?UF8
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package com.javaeye.common.util; ^W|B Xxo
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import java.util.List; w,fA-*bZ 0
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publicclass PaginationSupport { pJ Iq`)p5
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publicfinalstaticint PAGESIZE = 30; ^sR]w]cz.
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privateint pageSize = PAGESIZE; J0@<6~V6o
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privateList items; Ergh]"AD6-
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privateint totalCount; ^a&-GhX;
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privateint[] indexes = newint[0]; &eYnO~$!
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privateint startIndex = 0; 1oq5|2p
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public PaginationSupport(List items, int jU\vg;nr
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totalCount){ +cS%b}O`$
setPageSize(PAGESIZE); -F.A1{l[.
setTotalCount(totalCount); '|mVY; i[
setItems(items); UX3
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setStartIndex(0); {[~cQgCI
} wg<UCmfu!
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public PaginationSupport(List items, int V7}5Zw1
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totalCount, int startIndex){ 3T)GUzt`
setPageSize(PAGESIZE); +L(0R&C
setTotalCount(totalCount); i;4|UeUl
setItems(items); nX,2jT;@L
setStartIndex(startIndex); =WFn+#&^
} 9aYDi)
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public PaginationSupport(List items, int y{CyjYpz^
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totalCount, int pageSize, int startIndex){ : tKa1vL
setPageSize(pageSize); ~^#F5w"
setTotalCount(totalCount); #jdo54-
setItems(items); tmM8YN|
setStartIndex(startIndex); 6E~T$^Q}
} zrD];DP
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publicList getItems(){ > <cK
return items; 1<Fh
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} (#6E{@eq
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publicvoid setItems(List items){ *~b3FLzq
this.items = items; n3w(zB
} MRzrZZ%LQ
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publicint getPageSize(){ ^6*LuXPv
return pageSize; $6\-8zNk
} ;4DqtR"7Y
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publicvoid setPageSize(int pageSize){ |BrD:+
this.pageSize = pageSize; oNV5su
} =Kdd+g!
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publicint getTotalCount(){ NPjh2 AJm
return totalCount; #$trC)? ~q
} _2*Ryz
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publicvoid setTotalCount(int totalCount){ ZZ 1s}TG
if(totalCount > 0){ M
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this.totalCount = totalCount; @o&.]FZs
int count = totalCount / Gt{'` P,&9
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pageSize; WU oGIT'
if(totalCount % pageSize > 0) @R+bR<}]
count++; \Kh@P*7
indexes = newint[count]; E]x)Qr2Ju
for(int i = 0; i < count; i++){ hVQ
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indexes = pageSize * c-S_{~~
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} XRU^7@Ylks
}else{ 9d ZE#l!Q
this.totalCount = 0; }T!2IaAB
} AEx|<E0
} wm@/>X
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publicint[] getIndexes(){ rTJv>Jjld
return indexes; q3.L6M
} 3wRk -sl
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publicvoid setIndexes(int[] indexes){ <.c@l,[.z
this.indexes = indexes; JDO5eEwj
} z?C;z7eT
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publicint getStartIndex(){ F^iv1b
return startIndex; F_Q,j]0
} RfPRCIo
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publicvoid setStartIndex(int startIndex){ ![H!Y W'
if(totalCount <= 0) {,r7dxI)`
this.startIndex = 0; .;gK*`G2W)
elseif(startIndex >= totalCount) ;1Kxqpz_i
this.startIndex = indexes IT \Pj_
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[indexes.length - 1]; !6:q#B*
elseif(startIndex < 0) -BWkPq!
this.startIndex = 0; !A>VzW
else{ p^_E7k<ag
this.startIndex = indexes bI^zwK,@4
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[startIndex / pageSize]; o!Vs{RRu}
} ag6hhkjA
} xJ"CAg|B
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publicint getNextIndex(){ U].u) g$
int nextIndex = getStartIndex() + j[/'`1tOe
m.~&n!1W*`
pageSize; x~."P*5
if(nextIndex >= totalCount) \Fhk>
return getStartIndex(); Uk5O9D0
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else 5- Q`v/w;
return nextIndex; )2Gp3oD?
} HLMEB0zh^
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publicint getPreviousIndex(){ M4a-+T"
int previousIndex = getStartIndex() - K7&A^$`
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pageSize; 1m-"v:fT5D
if(previousIndex < 0) lu@#)
return0; (]BZ8GOx
else *"E?n>b
return previousIndex; 9E{Bn#
} eK"B.q7
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} +NRn>1]
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抽象业务类 x>Ah4ad
java代码: YWA:741
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/** FAu G`zu
* Created on 2005-7-12 an3HKfv
*/ ;??wLNdf-
package com.javaeye.common.business; Mj$dDtw
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import java.io.Serializable; 3mn0
import java.util.List; +j 5u[X
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import org.hibernate.Criteria; 1QRE-ndc
import org.hibernate.HibernateException; P9J3Ii!
import org.hibernate.Session; 8|[\Tp:;
import org.hibernate.criterion.DetachedCriteria; 78tWzO
import org.hibernate.criterion.Projections; :V2j'R,
import <p(&8P
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org.springframework.orm.hibernate3.HibernateCallback; D%LM"p
import *?oQ6g(Nz
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org.springframework.orm.hibernate3.support.HibernateDaoS 5|1&s3/f
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upport; Yfy6o6*:
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import com.javaeye.common.util.PaginationSupport; XKp %7;
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public abstract class AbstractManager extends k>{i_`*
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HibernateDaoSupport { q{f%U.
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privateboolean cacheQueries = false; :o$ R@l
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privateString queryCacheRegion; e#k9}n^+
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publicvoid setCacheQueries(boolean pooi8" G
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cacheQueries){ t; n6Q0
this.cacheQueries = cacheQueries; h`%K\C
} c%)uG _
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publicvoid setQueryCacheRegion(String 4:cbasy
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queryCacheRegion){ QN-n9f8
this.queryCacheRegion = CzzG
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queryCacheRegion; &+`l
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} NpD}7t<EF
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publicvoid save(finalObject entity){ %e7{ke}r
getHibernateTemplate().save(entity); oKt<s+r
} X5wS6v)#(
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publicvoid persist(finalObject entity){ /+RNPQO O
getHibernateTemplate().save(entity); #2DH_P
} z/fRd6|[
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publicvoid update(finalObject entity){ .mDqZOpf=4
getHibernateTemplate().update(entity); |]A{8BBC
} ao{>.b
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publicvoid delete(finalObject entity){ RYE::[O7
getHibernateTemplate().delete(entity); &X+V}
} E yNI]XEj
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publicObject load(finalClass entity, Z/wh?K3y
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finalSerializable id){ *U54x
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return getHibernateTemplate().load W~k!qy `
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(entity, id); -f9M*7O<gf
} K?[pCF2C
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publicObject get(finalClass entity, Tc:W=\ <
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finalSerializable id){ =AL95"cH~
return getHibernateTemplate().get *{4cc
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(entity, id); Pms3X
} xOT'4v&.
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publicList findAll(finalClass entity){ `r*6P^P
return getHibernateTemplate().find("from q'(WIv@
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" + entity.getName()); -(cm
} #]lUJ
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publicList findByNamedQuery(finalString Wlg(z%
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namedQuery){ + {hxEDz
return getHibernateTemplate y^@%Xrs
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().findByNamedQuery(namedQuery); )lw7W9
} MruWt*
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publicList findByNamedQuery(finalString query, nNhN:?
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finalObject parameter){ b V9Z[[\
return getHibernateTemplate Ysr{1! K
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().findByNamedQuery(query, parameter); p~8~EQFj
} 3]N}k|lb%
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publicList findByNamedQuery(finalString query, tB_ V%qH
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finalObject[] parameters){ uTl:u
return getHibernateTemplate /kw4":{]
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().findByNamedQuery(query, parameters); ^OBaVb
} c4-&I"z
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publicList find(finalString query){ s=%HT fw
return getHibernateTemplate().find p,tB
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(query); xh-[]Jz(
} s`#hk^{
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publicList find(finalString query, finalObject w:Lu
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parameter){ "~V}MPt
return getHibernateTemplate().find B4|`Z'U#;
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(query, parameter); UkqLLzL
} rM?D7a{q
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public PaginationSupport findPageByCriteria 0H>Fyl2_
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(final DetachedCriteria detachedCriteria){ q #p)E=$
return findPageByCriteria `% ENGB|
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Q?"[zX1
} /6q/`vx@
}TF<C!]
public PaginationSupport findPageByCriteria 6U&Uyd)
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(final DetachedCriteria detachedCriteria, finalint cw5YjQ8 9
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startIndex){ 3P6'*pZ
return findPageByCriteria &R5M&IwL
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(detachedCriteria, PaginationSupport.PAGESIZE, D{loX6
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startIndex); $U8ap4EXM
} j2P|cBXu
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public PaginationSupport findPageByCriteria _yoG<qI
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(final DetachedCriteria detachedCriteria, finalint I"!gzI`Sd
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pageSize, )I>rC%2P
finalint startIndex){ ks r5P~
return(PaginationSupport) #!5Nbe
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getHibernateTemplate().execute(new HibernateCallback(){ 7S1!|*/
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publicObject doInHibernate 2ga}d5lu
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(Session session)throws HibernateException { ; Q 6:#
Criteria criteria = N|~&Q!A&
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detachedCriteria.getExecutableCriteria(session); <Z__Q
int totalCount = rL
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((Integer) criteria.setProjection(Projections.rowCount 41zeN++
.lFSFJ ??
()).uniqueResult()).intValue(); IRU2/Y cg
criteria.setProjection gU~)(|Nu.
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(null); #_7c>gn
List items = %nC Uct@c
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criteria.setFirstResult(startIndex).setMaxResults @s@
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(pageSize).list(); \1MDCP9:
PaginationSupport ps = d+;wDu
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new PaginationSupport(items, totalCount, pageSize, YHA[PF
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startIndex); +|H'Ij$
return ps; ~ZNhU;%YW
} Q|1bF!#(1
}, true); &7W6IM
} "n
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public List findAllByCriteria(final q
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DetachedCriteria detachedCriteria){ y2U:( H:l!
return(List) getHibernateTemplate ?qbp
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().execute(new HibernateCallback(){ RnrM
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publicObject doInHibernate 1v4kN
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(Session session)throws HibernateException { 5QSmim
Criteria criteria = 1P[Lz!C
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detachedCriteria.getExecutableCriteria(session); nGbrWu]w
return criteria.list(); sy?>e*-{
} ?c2TT
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}, true); B1M/5cr.
} VM,ZEt3Vy
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public int getCountByCriteria(final +o3g]0
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DetachedCriteria detachedCriteria){ 8<kme"%s
Integer count = (Integer) #~+#72+x7
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getHibernateTemplate().execute(new HibernateCallback(){ vf=
publicObject doInHibernate U %ESuq#
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(Session session)throws HibernateException { +i^s\c!3;
Criteria criteria = gAj)3T@
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detachedCriteria.getExecutableCriteria(session); 9CNHjs+-}s
return K_5&_P1
@5y(>>C}8%
criteria.setProjection(Projections.rowCount vxeT[/6i
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()).uniqueResult(); r$F]e]Ic\
} p.9v<I%0
}, true); *[H+8/n_
return count.intValue(); h9I)<_}R
} X*"Kg
} nIjQLx
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用户在web层构造查询条件detachedCriteria,和可选的 !I[n|r "
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 32iI :u
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PaginationSupport的实例ps。 >, E$bm2
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ps.getItems()得到已分页好的结果集 6p"c^
ps.getIndexes()得到分页索引的数组 IDh`0/i]
ps.getTotalCount()得到总结果数 >bN~p
ps.getStartIndex()当前分页索引 <L~xR5
ps.getNextIndex()下一页索引 sAoM=n}!
ps.getPreviousIndex()上一页索引 zy[=OX+
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ;g:bn5G
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 IxZ.2 67
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一下代码重构了。 ~5NGDT#L*
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我把原本我的做法也提供出来供大家讨论吧: HF: T]n,
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首先,为了实现分页查询,我封装了一个Page类: Wi?%)hur
java代码: DME?kh>7
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/*Created on 2005-4-14*/ c@-K
package org.flyware.util.page; Zd U{`>v
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/** K$cIVsfr
* @author Joa g/,Bx!'8p
* \Byk`}
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*/ B bw1k
publicclass Page { SECQVA_y`
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/** imply if the page has previous page */ V;-.38py
privateboolean hasPrePage; Ue#yDTjc
=Rx?6%
/** imply if the page has next page */ )v=G}j^
privateboolean hasNextPage; cXcx_-
(VaN\+I:T
/** the number of every page */ RVnyl`s
privateint everyPage; h+3Z.WKhwP
YC&jKx .>
/** the total page number */ g0j4<\F2\
privateint totalPage; lo UwRz
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/** the number of current page */ KWJgW{{v
privateint currentPage; :6$4K"^1
bmVgTm&
/** the begin index of the records by the current W)!{U(X
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query */ g#bu_E61B
privateint beginIndex; o,Zng4NY
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/** The default constructor */ :"P hkR
public Page(){ y)/$ge_U
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} NhK(HTsvK
!)/iRw9re
/** construct the page by everyPage "YzTMKu
* @param everyPage c =N]!
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* */ X;6r$
public Page(int everyPage){ to!W={S<ol
this.everyPage = everyPage; {QS@Ugf
} e#6&uFce
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/** The whole constructor */ $',GkK{NX
public Page(boolean hasPrePage, boolean hasNextPage, Xc2B2c
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int everyPage, int totalPage,
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int currentPage, int beginIndex){ wEfz2Eq
this.hasPrePage = hasPrePage; C*s0r;
this.hasNextPage = hasNextPage; rF'^w56
this.everyPage = everyPage; R'9@A\7#
this.totalPage = totalPage; %V %#y $l
this.currentPage = currentPage; JQ@`EV9,
this.beginIndex = beginIndex; 9<A\npD
} HcBH!0
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/** pl#o!j( i
* @return ^wO_b'@v
* Returns the beginIndex.
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*/ 1&% d
publicint getBeginIndex(){ Y!a+#N!
return beginIndex;
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} t$y&=v
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/** lNaez3
* @param beginIndex Ie2w0Cs28
* The beginIndex to set. Xrj(,|
*/ =tf@4_
publicvoid setBeginIndex(int beginIndex){ kg?T$}O
this.beginIndex = beginIndex; 11B{gUv.]
} Y-%l7GErhL
mF*?e/
/** /h7>Z9T
* @return Y*kh$E%<#
* Returns the currentPage. DYAwQ"i;6
*/ Pv7f
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publicint getCurrentPage(){ -yl4tW
return currentPage; 3%[)!zKv
} miG;]-"^
-; us12SZ
/** P^b:?%
* @param currentPage tIxhSI^
* The currentPage to set. ~"JE![XR
*/ Uin k
publicvoid setCurrentPage(int currentPage){ ?v"K1C1.
this.currentPage = currentPage; 7#Uz*G\iZ
} hB
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/** 'z +$3\5L
* @return ez^*M:K
* Returns the everyPage. + 9\:$wMN
*/ 8Fd1;G6
publicint getEveryPage(){ uv|eVT3jNs
return everyPage; "$~}'`(]
} W(&Go'9e"
o\@ A2r3
/** agU%z:M{
* @param everyPage N"Y K@)*Q
* The everyPage to set. :jk)(=^
*/ ~{7zm"jN
publicvoid setEveryPage(int everyPage){ {WYu0J@
this.everyPage = everyPage; ;L
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} jU]]:S4xD/
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/** &547`*
* @return BaWQ<T8p8
* Returns the hasNextPage. [!J
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*/ Q?
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publicboolean getHasNextPage(){ ?qf:_G
return hasNextPage;
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} :(bdI]
3 {NaZIk
/** DA+A >5/
* @param hasNextPage ZL4l
(&"
* The hasNextPage to set. n0+g]|a
AF
*/ V17>j0Ev$W
publicvoid setHasNextPage(boolean hasNextPage){ 9tzoris[~
this.hasNextPage = hasNextPage; }zkL[qu;
} c!\.[2n
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/** qs6Nb'JvQR
* @return 935-{h@k
* Returns the hasPrePage. ?(5o@Xq
*/ U6c)"^\
publicboolean getHasPrePage(){ gt
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return hasPrePage; pau*kMu^}
} tJUVw=
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/** Ne &Xf
* @param hasPrePage 6Gs{nFw
* The hasPrePage to set. ]regi- LGU
*/ DAjG*K{
publicvoid setHasPrePage(boolean hasPrePage){ +"k.E
x0:
this.hasPrePage = hasPrePage; c@RT$Q9j
} q%OcLZ<,
p+orBw3
/** X|X4L(i
* @return Returns the totalPage. +dqk6RE
* J"%8:pL
*/ %==G+S{
publicint getTotalPage(){ TA Ftcs:
return totalPage; ~gu=x&{
} -Nsk}Rnk*
siZr@g !L
/** C-Nuy1o
* @param totalPage J?._/RL8-
* The totalPage to set. qq
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*/ AI&qU/}
publicvoid setTotalPage(int totalPage){ \bU`
this.totalPage = totalPage; yJDeX1+,
} /3J z3
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} c*N50%=4
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nY OY"'z
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 )HEfU31IC
WHp97S'd
个PageUtil,负责对Page对象进行构造: TNh=4xQ}
java代码: vTpStoUM
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/*Created on 2005-4-14*/ d2RnQA
package org.flyware.util.page; SXQ@;=]xV
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import org.apache.commons.logging.Log; r)gCTV(kb
import org.apache.commons.logging.LogFactory; &svx@wW
Vd,' s
/** 7e1dEgn
* @author Joa @'*eC}\E
* 'z)hG#{I
*/ [-4KY4R
publicclass PageUtil { K'x4l,rq
`q%U{IR
privatestaticfinal Log logger = LogFactory.getLog dw~[9oh
):3MYSqX
(PageUtil.class); a* D,*C5}
v9u<F6
/** |)9thIQF
* Use the origin page to create a new page !6M Bxg >
* @param page OFL|RLiD
* @param totalRecords -^yXLa;D
* @return $50\"mo~z
*/ +fM&su=wl
publicstatic Page createPage(Page page, int S"zk!2@C
Vr 8:nP:
totalRecords){ M ~als3
return createPage(page.getEveryPage(), Q8;#_HE
(/&;jV2DD[
page.getCurrentPage(), totalRecords); ^pj>9%
} qB:AkMd&
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/** .hKhrcQp
* the basic page utils not including exception 'qjX$]H
'fIHUw|
handler rOW;yJ[
* @param everyPage Kv}k*A% S
* @param currentPage %4,xx'`
* @param totalRecords e8oKn&
* @return page fmFzW*,E
*/ S.: 7k9
publicstatic Page createPage(int everyPage, int \^9pW 2v
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currentPage, int totalRecords){ !n eo\
everyPage = getEveryPage(everyPage); UgR:qjI
currentPage = getCurrentPage(currentPage); _5b0wdB
int beginIndex = getBeginIndex(everyPage, 6a*83G,k
RwW$O@0
currentPage); ?mMW*ico
int totalPage = getTotalPage(everyPage, :s"2Da3B
W"Z#Fs{n8
totalRecords); 'G8 ?'u_)
boolean hasNextPage = hasNextPage(currentPage, 1SUzzlRx
ll%G!VR
totalPage); :N2E}hxk
boolean hasPrePage = hasPrePage(currentPage); P[FV2R~
T^]7R4Fg
returnnew Page(hasPrePage, hasNextPage, /YFa
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everyPage, totalPage, 3htq[Ren
currentPage, it)ZP H
'd/*BjNp)
beginIndex); 9*\g`fWc}{
} Wwhgo.Wx
G6V/S aD
privatestaticint getEveryPage(int everyPage){ :m Kxa
return everyPage == 0 ? 10 : everyPage; Me,<\rQ
} TGf;_)El
XFQNr`
privatestaticint getCurrentPage(int currentPage){ +Rqbf
return currentPage == 0 ? 1 : currentPage; |c0,
} 4z_n4=
F.?01,J=1
privatestaticint getBeginIndex(int everyPage, int BqB|Fo
Ns<?b;aK
currentPage){ \lEkfcc
return(currentPage - 1) * everyPage; zb :kanb-
} W pN.]x
& fu z2xv
privatestaticint getTotalPage(int everyPage, int 9Kbw
GmSU
k][h9'
totalRecords){ 2Lfah?Tx~C
int totalPage = 0; E]1##6Ae
V&*D~Jq
if(totalRecords % everyPage == 0) NEVp8)w
totalPage = totalRecords / everyPage; s?c JV`
else u1^\MVO8
totalPage = totalRecords / everyPage + 1 ; ?YBaO,G9o
]g,lRG
return totalPage; *~2cG;B"e
} Pu;yEh
uw33:G
privatestaticboolean hasPrePage(int currentPage){ t'g^W
return currentPage == 1 ? false : true; mb1Vu
} %
5z
gd>
HCj>,^<h
privatestaticboolean hasNextPage(int currentPage, mI"D(bx\
^m%52Tm
h
int totalPage){ w"8V0z
return currentPage == totalPage || totalPage == NiA4JgM]v
:,
_!pe;H
0 ? false : true; TQc@lR!
} ?3q@f\fZ
R0wf#%97
aQUGNa0+d
} {DwIjy31T
m#\[m<F
,Dp0fauJ
kRlA4h1u_$
{kL&Rv%'
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 3-|3`(
=6\LIbO
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 .z-UOyer
UpfZi9v?W
做法如下: J,5+47b1}R
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 x[X`a
$a(`ve|
的信息,和一个结果集List: 1~\M!SQ)
java代码: >c~RI7uu
~3CVxbB^<
IQnIaZ
/*Created on 2005-6-13*/ bL1m'^r
package com.adt.bo; (3;@^S4&w
zzIr2so
import java.util.List; ~<)vKk
|V|+lx'sc
import org.flyware.util.page.Page; %3o`j<
KX4],B5 +
/** 5iM[sg[y9
* @author Joa %8r/oS
*/ hXB|g[zT
publicclass Result { 9Ah[rK*}
8-Me.2K
private Page page; |"]PCb)!
x({C(Q'O
private List content; tR)H~l7q
80;n|nNB
/** FTf<c0
* The default constructor 2@khSWV
*/ 4kl Ao$
public Result(){ i9 A ~<
super(); [4Q"#[V&9
} 2k5/SV
X
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9H#
/** I#G0, &Gv
* The constructor using fields Eu,`7iQ?(
* 27A!\pn
* @param page "G?Yrh
* @param content d
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*/ }dYBces
public Result(Page page, List content){ 2+Rv{%
this.page = page; 1^G{tlA-
this.content = content; X}A'Cg0y
} _[h8P9YI4
Z(GfK0vU
/** W|5_$p
* @return Returns the content. !3qVB
*/ OW@\./nM
publicList getContent(){ '0Q,
return content; PXk?aJ
} !L24+ $
Jxl6a:
/** 7cTk@Gq
* @return Returns the page. R 94^4I
*/ I)SG wt-
public Page getPage(){ z(13~38+
return page; wvby?MhPY
} K8I$]M
6'-As=iw
/** 1iBP,:>*
* @param content jZ*WN|FK?
* The content to set. rS8 w\`_
*/ ~O6\6$3b5E
public void setContent(List content){ $E!J:Y=
this.content = content; j\&pej
} ~d
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v&
$k9)]
/** * ?Jz2[B
* @param page r@G#[.*A>
* The page to set. CH#k(sy
*/ f 2YLk
publicvoid setPage(Page page){ ;2xO`[#
this.page = page; 9jir*UI
} Af(WV>'
} ipE]}0q
<wd]D@l7r
+9;2xya2
Z u*K-ep"
!wz/cM;
2. 编写业务逻辑接口,并实现它(UserManager, s>n(`?@L
9pKGr@ &
UserManagerImpl) jeUUa-zR3
java代码: aHzHvl
b;cMl'
q(M:QWA q
/*Created on 2005-7-15*/ <%?#AVU[
package com.adt.service; ]/X(V|t
p
*w$:L
import net.sf.hibernate.HibernateException; ~ 5"JzT
@OpNHQat9
import org.flyware.util.page.Page; dt\jGD
rf&M!d}!
import com.adt.bo.Result; %3r:s`{
qoMfSz"(
/** :mcYZPX#
* @author Joa zbkMFD.{y
*/ /iaf ^
>
publicinterface UserManager { C~%
1w%nn
ay
)/q5
public Result listUser(Page page)throws #U
mF-c
5` D-
HibernateException;
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"2ru 7Y"
} ne}+E
oXsL9,
Dh4
6o|P
8 .>/6M
iUk-'
java代码: W i.5Y{
t<iEj"5
)FN;+"IJ
/*Created on 2005-7-15*/ KJn!Ap
package com.adt.service.impl; e.d
#wyeX
-e GL) M
import java.util.List; W!Gdf^Yy<
$tqJ/:I
import net.sf.hibernate.HibernateException; T#@lDpO
K$ }a8rH
import org.flyware.util.page.Page;
dq;|?ESP
import org.flyware.util.page.PageUtil; AM"jX"F9/
Io`P,l:
import com.adt.bo.Result; qy1F*kY
import com.adt.dao.UserDAO; hB;VCg8
import com.adt.exception.ObjectNotFoundException; |KI UgI
import com.adt.service.UserManager; Lo.rvt
am1[9g8L
/** jEdtJEPa
* @author Joa 0fXLcal
*/ SMr13%KN/
publicclass UserManagerImpl implements UserManager { Z4K+ /<I
CBYX]
private UserDAO userDAO; {=2DqkTD
G.VuKsP]
/** f_ ^1J
* @param userDAO The userDAO to set. m0w;8uF2UV
*/ ~+X9g
publicvoid setUserDAO(UserDAO userDAO){ B<?[Mrdxw
this.userDAO = userDAO; DB526O*
[
} 6Q&r0>^{
WS8+7O'1\
/* (non-Javadoc) \2-@' ^i
* @see com.adt.service.UserManager#listUser N;oQ^B'
xiF7}]d+
(org.flyware.util.page.Page) }kHdK vZ
*/ P;[OWSR[d
public Result listUser(Page page)throws @:0ddb71
@!N-RQ&A
HibernateException, ObjectNotFoundException { bu7'oB~:V^
int totalRecords = userDAO.getUserCount(); 2aZw[7s
if(totalRecords == 0) Gc]~wD$
throw new ObjectNotFoundException
wm{3&m
mbRqJT>@
("userNotExist"); gF=jf2{YX
page = PageUtil.createPage(page, totalRecords); D%mXA70
List users = userDAO.getUserByPage(page); W1Lr_z6
returnnew Result(page, users); tY${M^^<J
} vr^~yEr
{#P`^g
} x&Vm!,%:1
,C.:;Ime({
hVT~~n`Rj
)5j;KI%t
hf/2vt
m
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 *_ Z#O,
,d+fDmm3
询,接下来编写UserDAO的代码: zJDSbsc$%
3. UserDAO 和 UserDAOImpl: N /$`:8"
java代码: =o}"jVE
nMfFH[I4
&;,,H< p
/*Created on 2005-7-15*/ 1(Y7mM8\
package com.adt.dao; 93qwH%
`!:q;i]}
import java.util.List; ,r^M?>
u?Tpi[
#
import org.flyware.util.page.Page; 5AS[\CB4
\I-#1M
import net.sf.hibernate.HibernateException; TC~Q
G$NW
v[@c*wo
/** 02`$OTKz
* @author Joa .#u_#=g?
*/ (6CN/A{qe
publicinterface UserDAO extends BaseDAO { M2x["
n,HE0Zn]Y_
publicList getUserByName(String name)throws OH^N" L
l.\re"Q
HibernateException; (bOpV>\Q7
Tu{&v'!j6
publicint getUserCount()throws HibernateException; f'I z
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.x`M<L#M(
publicList getUserByPage(Page page)throws \;-fi.Hrf$
XoLJ L]+?
HibernateException; 6$a$K,dZ
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} ;4M><OS!
a07@C
+uWDP.
RCTQhTy=
J89Dul l
java代码: @~<j&FTT
&R|/t:DN
M<SdPC(+
/*Created on 2005-7-15*/ &1l=X]%
package com.adt.dao.impl; Iz6y{E
WwF~d+>|C
import java.util.List; ,uw132<b
ONNpiK-
import org.flyware.util.page.Page; gj\)CBOv
q#Zs\PD
import net.sf.hibernate.HibernateException; W"{v2x i
import net.sf.hibernate.Query; QB:i/9
#po5_dE\*
import com.adt.dao.UserDAO; lf>*Y.!@me
}pk#!N
/** n9pN6,o+
* @author Joa 1Gt/Tq$_b
*/ wxm:7$4C
public class UserDAOImpl extends BaseDAOHibernateImpl 6Ao%>;e*
LA_3=@2.H
implements UserDAO { n .!Ym
X4
*`j-i
/* (non-Javadoc) _A<u#.yd
* @see com.adt.dao.UserDAO#getUserByName }?cGf-c
6:U$w7P0
e
(java.lang.String) 6.5T/D*TT
*/ lPLz@Up~
publicList getUserByName(String name)throws _|72r}j
2fU$J>Y
HibernateException { !zPG?q]3
String querySentence = "FROM user in class "dR|[a<#g
h2ZkCML
com.adt.po.User WHERE user.name=:name"; |/gW_;(
Query query = getSession().createQuery -~eJn'W
mcz+P |
(querySentence); f:g,_|JD$
query.setParameter("name", name); |K?#$~
return query.list(); ;})5:\h
} bifS 2>c
]M)O YY
/* (non-Javadoc) ZpUCfS)|&
* @see com.adt.dao.UserDAO#getUserCount() j8|g!>Nv
*/ =fm]D l9h*
publicint getUserCount()throws HibernateException { Ggh.dZI4
int count = 0; *A}cL
String querySentence = "SELECT count(*) FROM g}laG8
st"{M\.p
user in class com.adt.po.User"; Oz|K8p
Query query = getSession().createQuery 79\JxiSB
zkTp`>9R
(querySentence); |IunpZV
count = ((Integer)query.iterate().next Ngb(F84H?
awvDe
()).intValue(); h25G/`
return count; IHgeQ F
~
} f84:hXo6
,uzN4_7u
/* (non-Javadoc) *. 3N=EO
* @see com.adt.dao.UserDAO#getUserByPage ,>t69 Ad
\#68;)+=
(org.flyware.util.page.Page) Ku&!?m@C
*/ %/>xO3"T
publicList getUserByPage(Page page)throws b 1&i# I?{
K^_i%~
HibernateException { 9]t[J_YM
String querySentence = "FROM user in class "cTncL
[-&L8Un
com.adt.po.User";
)1g"?]
Query query = getSession().createQuery <foCb%$(?
%>g W9}kB
(querySentence); #W.vX?-'0
query.setFirstResult(page.getBeginIndex()) y=Mq(c:'UN
.setMaxResults(page.getEveryPage()); b':|uu*/
return query.list(); }F+zs*S
} Cf B.ZT
9h/>QLx
} P}.7Mehf
AxxJk"v'y
m/N dJMoN=
3] 1-M
OB~X/
至此,一个完整的分页程序完成。前台的只需要调用 "O8gJ0e
IVlf=k
userManager.listUser(page)即可得到一个Page对象和结果集对象 )
'j:
+UJuB
的综合体,而传入的参数page对象则可以由前台传入,如果用 _C\[DR0n
=)O,`.M.Y
webwork,甚至可以直接在配置文件中指定。 47r_y\U h
g%u&Zkevx
下面给出一个webwork调用示例: 56l@a{
java代码: ~}K5#<
8q`$y$06Dk
^-FRTC
/*Created on 2005-6-17*/ 8 6f2'o+
package com.adt.action.user; CF|]e:
GE|+fYVM-$
import java.util.List; WvHw{^(lF
(HoqR
import org.apache.commons.logging.Log; i&8FBV-
import org.apache.commons.logging.LogFactory; 2xw6 5z
import org.flyware.util.page.Page; iYnEwAoN;
&R~n>>c
import com.adt.bo.Result; qo)?8kx>l
import com.adt.service.UserService; '03->7V
import com.opensymphony.xwork.Action; %p&k5:4<"#
Av0y?oGH
/** ~j#~\Ir
* @author Joa >:=|L%]s;\
*/ (;. AS
publicclass ListUser implementsAction{ -C#PQV
n;R#,!<P
privatestaticfinal Log logger = LogFactory.getLog `si#aU
@pGZLq
(ListUser.class); 7FN<iI&7\
W4;m H}#0
private UserService userService; /v095H@
!L5jj#0
private Page page; A?TBtAe
H'
T
privateList users; :V)lbn\
B12$I:x`
/* C0=9K@FCb
* (non-Javadoc) y}C`&nW[=
* mVtXcP4b
* @see com.opensymphony.xwork.Action#execute() e&eW|E
*/ ;M]C1!D9#
publicString execute()throwsException{ yGg,$WM
Result result = userService.listUser(page); N8KQz_]9I
page = result.getPage(); @`FCiH M
users = result.getContent(); fAZiC+
return SUCCESS; )'l*Tl
} A?G IBjs
4`#F^2r!
/** vi@Lz3}::
* @return Returns the page. )m3q2W
*/ B7\k< Nit0
public Page getPage(){ OdMO=Hy6d
return page; ?Z\Yu'
} 2!N8rHRt
J==SZ v
/** *M7E#bQ5B
* @return Returns the users. }0,>2TTDN
*/ dk8wIa"K`
publicList getUsers(){ elG;jB
return users; UEak^Mm;=2
} 4Ij-Ilg)%
<"o"z2
/** hO{cvHy`
* @param page .s/fhk,
* The page to set. *9ywXm&?
*/ RkFD*E$
publicvoid setPage(Page page){ u6:pV.p
this.page = page; =O|c-k,f@
} 2A4FaBq"
2?@j~I=s2h
/** &Bx
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* @param users wix5B@
* The users to set. Li 2Zndp
*/ wwKh CmH
publicvoid setUsers(List users){ n(~\l#o@
this.users = users; eUS
} 'H9=J*9oG
Bs`$ i ;&
/** ^4%Zvl
* @param userService -ZW0k@5g
* The userService to set. 9Pd*z>s
*/ _Fp>F
publicvoid setUserService(UserService userService){ OPpjuIRv
this.userService = userService; n{*e 9Aw
} nZR!*$}A
} s!/TU{8J
I[o*RKT'"
df+t:a
P`U<7xF~
M8w5Ob
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, !BU)K'mj
Do?P<x o
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 nW\(IkX\
;%J5=f%z)
么只需要: R)!`JKeO/
java代码: t?;T3k[RM
4X
NxI1w)
b(GFMk
<?xml version="1.0"?> ,]R8(bD)
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 3E} An%
8:ggECD
1.0//EN" "http://www.opensymphony.com/xwork/xwork- O`FqD{@V
4n
3Tp{Y}
1.0.dtd"> T0j2a&Pv
%;`>`j5
<xwork> p]W+eT
3l!NG=R
<package name="user" extends="webwork- l#3($QV,
s(ROgCO
interceptors"> ETv9k g
2k7bK6=nm
<!-- The default interceptor stack name ~7q uTp)
Vu0KtG9
--> B~r}c4R{7
<default-interceptor-ref \zXlN
x:K?\<
name="myDefaultWebStack"/> >L((2wfiN
cu#e38M&eE
<action name="listUser" bC@k>yC-
vnX
class="com.adt.action.user.ListUser"> ~4.r^)\
<param gLj?Ys
a7H0!9^h
name="page.everyPage">10</param> f<[jwhCWV
<result i~=s^8n`l
l52a\/
name="success">/user/user_list.jsp</result> jStmS2n
</action> !J>A,D"-
\hk/1/siyF
</package> [2$4| ;7
g=]&A
</xwork> g;F"7
^sg
}4jC_ZAupt
_|c&@M
#S
QXTR
<FFJzNc+
cErI%v}v0
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 bk#xiuwT
5$l9@0D.\
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 mAqDjRV1
sB}]yw
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 $,1dQeE
-@%%*YI>
@
"d2.h
`LP!D
H^c0Kh+
我写的一个用于分页的类,用了泛型了,hoho X\GM/A
u'9gVU B
java代码: dK?);*w]
&TN2 HZ-bJ
Yt1mB[&f^
package com.intokr.util; N}/>r D
8q_0,>w%
import java.util.List; 4-4?IwS
G^h_YjR`*
/** /MMtTB
H
* 用于分页的类<br> DMgBcP
* 可以用于传递查询的结果也可以用于传送查询的参数<br> Hw_o
w?
* ^^LjI
* @version 0.01 vd~U@-C=R
* @author cheng :F|\Ij0T
*/ *c]KHipUIS
public class Paginator<E> { <,39_#H?F3
privateint count = 0; // 总记录数 &W_th\%
privateint p = 1; // 页编号 4be> `d5j
privateint num = 20; // 每页的记录数 4!%]fg}Um
privateList<E> results = null; // 结果 NXoK@Y
744=3v
/** =:$) Z
* 结果总数 z4Oo@3$\R
*/ to3?$-L
publicint getCount(){ aPIr_7e
return count; L4974E?S
} 3A0_C?E
fp !:u
publicvoid setCount(int count){ L=A\ J^%
this.count = count; X\2_;zwf
} @@pq'iRn
\XH@b6{
/** $+VgDe5{S
* 本结果所在的页码,从1开始 tP'GNsq+m
* 8GB]95JWwp
* @return Returns the pageNo. ;<6"JP>0
*/ Du_$C[
publicint getP(){ ;w6s<a@Zh
return p; d.}}s$Q
} jn=ug42d
Lt<oi8'N
/** Z.jCera.
* if(p<=0) p=1 3ut_Bt\
* gA
+:CgQ
* @param p OD4W}Y.
*/ jb@\i@-
publicvoid setP(int p){ {g=b]yg\o
if(p <= 0) edN8-P(
p = 1; z-Hkz
this.p = p; (&Q)EBdm
} sco
uO$K
"Gh#`T0#a
/** )+GX<2_
* 每页记录数量 ,VG9)K1K
*/ zzJ^x8#R
publicint getNum(){ &-F"+v,+
return num; *,jqE9:O
} 5Bj77?Z
9".Uc8^p/F
/** 8&Wx@QI
* if(num<1) num=1 :uR>UDlPX
*/ ZQLB`n@
publicvoid setNum(int num){ {5x>y:v
if(num < 1) Y@:3 B:m#
num = 1; `1,eX)S
this.num = num; HD|sr{Z%
} F?2FITi_V
+FBi5h
/** M)=|<h"F
* 获得总页数 )<'yQW=6
*/ h#R&=t1,^
publicint getPageNum(){ ;G Qm[W([
return(count - 1) / num + 1; Oy'0I,
} _W+Q3Jx-(
_h~p:=
/** c%yh(g
* 获得本页的开始编号,为 (p-1)*num+1 fv|%Ocm
*/ 1}DerX 6
publicint getStart(){ :|($,3*
return(p - 1) * num + 1; It\BbG=
} /'`6
;
uRN
7j R7
/** P%jkKE?B4
* @return Returns the results. (\uAAW"
*/ 3GINv3_
publicList<E> getResults(){ x 8M#t(hw
return results; y[p6y[r*
} Bfn]-]>sD
CRd_}
public void setResults(List<E> results){ -&7=uRQk
this.results = results; Ps |QW
} "o<D;lO
_DrnL}9I7
public String toString(){ y3AL)
StringBuilder buff = new StringBuilder f-s~Q4
kI]=&Rw
(); {"}+V`O{
buff.append("{"); 7(5]Ry:
buff.append("count:").append(count); yHtGp%j
buff.append(",p:").append(p); QS%,7'EG
buff.append(",nump:").append(num); wK ][qZ ]
buff.append(",results:").append e18T(g_i
W&LBh%"g
(results); ZnQ27FcW
buff.append("}"); % IPyCEJD
return buff.toString(); ~q5-9{ma
} 2}|vWKej{
k$?&]! <o
} l]/> `62
7j95"mI
:(RL8