Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 g0R[xOS|
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 /aqEJGG>
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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 bS!\#f%9"
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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 ,6"l (]0
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分页支持类: wkb$^mU
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java代码: N4!<Xj
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package com.javaeye.common.util; I;MD>%[W,
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import java.util.List; V5mTu)tp5
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publicclass PaginationSupport { ,kM)7!]N
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publicfinalstaticint PAGESIZE = 30; #x@ eDnb_
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privateint pageSize = PAGESIZE; 3$/ 4wH^
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privateList items; [\e@_vY@OH
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privateint totalCount; z\!K<d"Xv
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privateint[] indexes = newint[0]; Ip
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privateint startIndex = 0; cj$6
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public PaginationSupport(List items, int H=^K@Ti:
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totalCount){ Ey`h1Y
setPageSize(PAGESIZE); Gc,_v3\
setTotalCount(totalCount); pPro }@@
setItems(items); 5/0j}_pP
setStartIndex(0); 1DJekiWf
} NL"G2[e
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public PaginationSupport(List items, int $jzFc!rs
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totalCount, int startIndex){ dp5cDF}l
setPageSize(PAGESIZE); 0 p uY"[c
setTotalCount(totalCount); HIvZQQW|
setItems(items); P 7D!6q
setStartIndex(startIndex); F7}-!
} _e<o7Y@_
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public PaginationSupport(List items, int Dm0a.J v
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totalCount, int pageSize, int startIndex){ `ldz`yu6++
setPageSize(pageSize); Me3dpF
setTotalCount(totalCount); 2DDsWJ;
setItems(items); y/_XgPfWU
setStartIndex(startIndex); 0y#Ih {L
} |V,<+BEi
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publicList getItems(){ mEAXM1J|
return items; @x&P9M0g
} Sv[ 5NZn0&
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publicvoid setItems(List items){ @C8DZ5)
this.items = items; HL K@xKD<
} _8?o'<!8?^
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publicint getPageSize(){ /F/;G*n
return pageSize; XP?rOOn
} 6dqsFns}e
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publicvoid setPageSize(int pageSize){ Hf gz02Z$
this.pageSize = pageSize; b7:0#l$
} V|D]M{O
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publicint getTotalCount(){ Jf;?XP]z
return totalCount; olux6RP[B
} }?8uH/+ZA
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publicvoid setTotalCount(int totalCount){ :$3oFN*g
if(totalCount > 0){ 1OaXo!
this.totalCount = totalCount; (g!p>m!Z
int count = totalCount / UK[v6".^h
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pageSize; clO,}Ph>
if(totalCount % pageSize > 0) uKr1Z2
count++; SI:ifR&T
indexes = newint[count]; mh/n.*E7
for(int i = 0; i < count; i++){ 4Ft1@
indexes = pageSize * .p`
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i; 9"{W,'r&d
} HfNDD|Zz
}else{ `TLzVB-j3
this.totalCount = 0; W6c]-pc
} ]2SI!Ai7
} /B3R1kNf|
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publicint[] getIndexes(){ a}yXC<}$
return indexes; &dB-r&4;+
} kma?v B
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publicvoid setIndexes(int[] indexes){ m:QG}{<.h
this.indexes = indexes; B^ 7eo W
} a6xj\w
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publicint getStartIndex(){ RzKb{>
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return startIndex; l:B;zi`)oB
} 1`0#HSO
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publicvoid setStartIndex(int startIndex){ OW;tT=ql
if(totalCount <= 0) $^/0<i$
this.startIndex = 0; z9/G4^qF
elseif(startIndex >= totalCount) BHDML.r }M
this.startIndex = indexes 3Hi+Z}8
],etZ%z&
[indexes.length - 1]; >`RRP}u=u
elseif(startIndex < 0) Ut@RGg+f8
this.startIndex = 0; yBpk$
else{ ~"x5U{K48S
this.startIndex = indexes "8 )z=n
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[startIndex / pageSize]; v5}X+'
} {lG@hN'
} Rfb?f}j
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publicint getNextIndex(){ }j 5 a[L
int nextIndex = getStartIndex() + alMYk
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pageSize; Yf_6PGNzX
if(nextIndex >= totalCount) ='?:z2lJ
return getStartIndex(); q6#<[ 4?
else &7mW9]
return nextIndex; .1 )RW5|c
} 6aO2:|:yP
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publicint getPreviousIndex(){ +!t}
int previousIndex = getStartIndex() - }CL"S_>1
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pageSize; bp<^R
if(previousIndex < 0) l(W[_ D
return0; 4Aes#{R3v
else ,Dmc2D
return previousIndex; ]:]H:U]p
} Pf_F59"
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} jjs&`Fy,
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抽象业务类 }alj[)
java代码: B1
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/** klOp ^w
* Created on 2005-7-12 rnFM/GAy
*/ c~,23wP1
package com.javaeye.common.business; U'( sn
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import java.io.Serializable; c{#yx_)V&
import java.util.List; \0;(VLN'U
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import org.hibernate.Criteria; 8;P2A\X
import org.hibernate.HibernateException; i%Z2wP.o
import org.hibernate.Session; ;^u*hZN[Up
import org.hibernate.criterion.DetachedCriteria; Wl"0m1G
import org.hibernate.criterion.Projections; t G.(flW,
import ITJ q
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org.springframework.orm.hibernate3.HibernateCallback; k_|^ kdWJ
import -cF'2Sfr
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org.springframework.orm.hibernate3.support.HibernateDaoS 5AeQQU
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upport; l.)}t)my}
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import com.javaeye.common.util.PaginationSupport; -4#2/GXNO
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public abstract class AbstractManager extends \uOdALZ
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HibernateDaoSupport { `s#Hq\C
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privateboolean cacheQueries = false; A~(l{g
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privateString queryCacheRegion; KU9Z"9#
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publicvoid setCacheQueries(boolean SjEAuRDvUz
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cacheQueries){ ,1{Ep`
this.cacheQueries = cacheQueries; hqSJ(gs{
} :6kj EI
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publicvoid setQueryCacheRegion(String >-<8N-@"n
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queryCacheRegion){ WP**a Bp
this.queryCacheRegion = Q/>L_S
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queryCacheRegion; S]3Ev#>
} R\Z:n*
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publicvoid save(finalObject entity){ qk(P>q8[
getHibernateTemplate().save(entity); g+8hp@a
} nxm$}!Df
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publicvoid persist(finalObject entity){ 8[%Ao/m
getHibernateTemplate().save(entity); qa >Ay|92e
} [&S}dQ"
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publicvoid update(finalObject entity){ -ZOBAG*
getHibernateTemplate().update(entity); d^ ZMS~\*
} H&}ipaDO
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publicvoid delete(finalObject entity){ #<7O08:
getHibernateTemplate().delete(entity); o`,Qku k
} n}-3o]ku
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publicObject load(finalClass entity, |dE
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finalSerializable id){ 9?T{}| ?
return getHibernateTemplate().load G28O%jD?
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(entity, id); w2(guL($
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publicObject get(finalClass entity, 4B+9z^oQ
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finalSerializable id){ $WQq?1.9
return getHibernateTemplate().get 4IdT'
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(entity, id); O OFVnu
} L?&'xzt B
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publicList findAll(finalClass entity){ }*U[>Z-eO
return getHibernateTemplate().find("from 0Sl]!PZR1
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" + entity.getName()); ^
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} %%%fL;-y
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publicList findByNamedQuery(finalString Pj#'}ru!
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namedQuery){ wYsZM/lw
return getHibernateTemplate jMBiaX`F
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().findByNamedQuery(namedQuery); i@"e,7mSG
} <pLT'Y=
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publicList findByNamedQuery(finalString query, |Yi)"-
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finalObject parameter){ n7LfQWc
return getHibernateTemplate Ft{[ae?4
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().findByNamedQuery(query, parameter); 9$K;Raz%
} ?0*8RK
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publicList findByNamedQuery(finalString query, Nf,Z;5e
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finalObject[] parameters){ <S"~vKD'
return getHibernateTemplate De
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().findByNamedQuery(query, parameters); :Gqy>)CxX
} Tn-C>=tR~%
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publicList find(finalString query){ iyx>q!P
return getHibernateTemplate().find o(A|)c4k
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(query); #>;FUZuJr
} ]J1S#Q5'
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publicList find(finalString query, finalObject lw%?z/HDf
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parameter){ dmrps+L
return getHibernateTemplate().find `A%^UCd
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(query, parameter);
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} YL^=t^!4
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public PaginationSupport findPageByCriteria >P KBo
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(final DetachedCriteria detachedCriteria){ Zzua17
return findPageByCriteria &6 -k#r
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); !SOrCMHx
} 6"T['6:j
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public PaginationSupport findPageByCriteria H Yr}wG
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(final DetachedCriteria detachedCriteria, finalint ajhEL?%D
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startIndex){ DbX{#4lx
return findPageByCriteria {aKqXL[UP
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(detachedCriteria, PaginationSupport.PAGESIZE, `XTh1Z\
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startIndex); / RZR}
} fr6^nDY
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public PaginationSupport findPageByCriteria F^aR+m
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(final DetachedCriteria detachedCriteria, finalint
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pageSize, 9D\4n
finalint startIndex){ Uh}seB#mJj
return(PaginationSupport) d87vl13
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getHibernateTemplate().execute(new HibernateCallback(){ 7"X>?@
publicObject doInHibernate 4S0>-?{
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(Session session)throws HibernateException { ge3sU5iZ
Criteria criteria = $>M<j
f}c\_}(
detachedCriteria.getExecutableCriteria(session); txql 2
int totalCount = =`n]/L"Q
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((Integer) criteria.setProjection(Projections.rowCount =]R3& ]#n
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()).uniqueResult()).intValue(); ij5g^{_T;8
criteria.setProjection ;#G oGb4AM
jd`},X /
(null); tL
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List items = X8eJ4%
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criteria.setFirstResult(startIndex).setMaxResults 3q[WHwmm
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(pageSize).list(); k`HP"H
PaginationSupport ps = UAF<m1
$$Vt7"F
new PaginationSupport(items, totalCount, pageSize, _;A $C(
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startIndex); _STB$cZ
return ps; [//R ~i?
} V+-$jOh
}, true); <|O^>s;
} PALl sGlf
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public List findAllByCriteria(final NBh%:tu7M
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DetachedCriteria detachedCriteria){ xynw8;Y,
return(List) getHibernateTemplate 0XwHP{XaO
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().execute(new HibernateCallback(){ :^ i9]
publicObject doInHibernate g3@Rl2yQJ
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(Session session)throws HibernateException { ~wnOV#v
Criteria criteria = Z{IUy
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detachedCriteria.getExecutableCriteria(session); ^_I} x)i*@
return criteria.list(); M/D)".;
} B
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}, true); pZZgIw}aS
} LgmvKW|
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public int getCountByCriteria(final z9
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DetachedCriteria detachedCriteria){ xieP "6
Integer count = (Integer) 5lKJll^2:
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getHibernateTemplate().execute(new HibernateCallback(){ MJ<Jb ,D1
publicObject doInHibernate {cK^,?x
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(Session session)throws HibernateException { &Wp8u#4L
Criteria criteria = S,fCV~Cio?
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detachedCriteria.getExecutableCriteria(session); 5\mTr)\R
return 1:C:?ZC#c
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criteria.setProjection(Projections.rowCount wCMQPt)VS
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()).uniqueResult(); TG48%L
} m4K* <
}, true); Mj>}zbpk/
return count.intValue(); "}WJd$
} o 6 {\Zzp
} S&O3HC
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用户在web层构造查询条件detachedCriteria,和可选的 djQv[Vc{
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ubMOD<
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PaginationSupport的实例ps。 h[KvhbD3
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ps.getItems()得到已分页好的结果集 cxeghy:;U
ps.getIndexes()得到分页索引的数组 ,:Jus
ps.getTotalCount()得到总结果数 %\O#&=$E
ps.getStartIndex()当前分页索引 $aCd/&
ps.getNextIndex()下一页索引 3H\w2V
ps.getPreviousIndex()上一页索引 P;ZU-G4@
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Z0!5d<
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 Zd^6ulx
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一下代码重构了。 Eh</? Qv\
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我把原本我的做法也提供出来供大家讨论吧: Xm2\0=v5;
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首先,为了实现分页查询,我封装了一个Page类: 5FVndMM#y
java代码: p=GWq(S6
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/*Created on 2005-4-14*/ b2(RpY2Y
package org.flyware.util.page; .9*wY0:
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/** l5%G'1w#,j
* @author Joa !1T\cS#1%
* MfO:m[s
*/ d4:`@*
publicclass Page { CQ7{1,?2
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/** imply if the page has previous page */ gXT9 r' k
privateboolean hasPrePage; .xzEAu ;
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/** imply if the page has next page */ ?SQE5Z
privateboolean hasNextPage; |@?%Ct
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/** the number of every page */ :a8 YV!X
privateint everyPage;
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/** the total page number */ 'C$XS>S
privateint totalPage; #1c]PX
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/** the number of current page */ @Q&3L~K"
privateint currentPage; I
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/** the begin index of the records by the current kh~'Cn "O
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query */ r?m+.fJB
privateint beginIndex; j.~!dh$mg
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/** The default constructor */ -U~
public Page(){ 2Y}?P+:%>
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} H|ozDA
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/** construct the page by everyPage AIb2k
* @param everyPage xX3'bsN
* */ OJT1d-5p
public Page(int everyPage){ YzosZ! L!<
this.everyPage = everyPage; dpQG[vXe
} bn
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/** The whole constructor */ QY/hI`
public Page(boolean hasPrePage, boolean hasNextPage, DU%w1+u
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int everyPage, int totalPage, ~/NKw:
int currentPage, int beginIndex){ A,su;Qh
this.hasPrePage = hasPrePage; i'd2[A.7I
this.hasNextPage = hasNextPage; ,h|q i[7
this.everyPage = everyPage; f~E*Zz`;
this.totalPage = totalPage; MRU7W4W-~/
this.currentPage = currentPage; s}5cSU!|
this.beginIndex = beginIndex; ,Vd\m"K{
} 6cqP2!~
}:: S0l
/** l1ZY1#%j
* @return PcB_oG g
* Returns the beginIndex. Q
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*/ #T`t79*N
publicint getBeginIndex(){ 8x`.26p
return beginIndex; fQrhsuCrC
} HW&%T7
a
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/** dd2[yKC`
* @param beginIndex Y|8vO
* The beginIndex to set. \xg]oKbn
*/ Y`+=p@2O2o
publicvoid setBeginIndex(int beginIndex){ k6`6Mjbc
this.beginIndex = beginIndex; L
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} (F7(^.MG
j4=(H:c~E
/** zf3v5Hk
* @return yH][(o=2
* Returns the currentPage. AM=z`0so
*/ kq\)MQ"/X
publicint getCurrentPage(){ +C7 ~b~ %
return currentPage; zMIT}$L
} Zmbfq8K
dr4Z5mw"E
/** I ZQHu h
* @param currentPage No2b"G@
* The currentPage to set. t1E[uu ,V8
*/ 6c0>gUQx-
publicvoid setCurrentPage(int currentPage){ /0\
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this.currentPage = currentPage; @FdSFQ/9
} #plY\0E@
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/** q2HYiH^L
* @return 4k./(f2+
* Returns the everyPage. Ym;*Y !~[
*/ Bc3:}+l
publicint getEveryPage(){ ZiLj=bh
return everyPage; o1nURJ!
} (8_\^jJ
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/** ETs>`#`6o
* @param everyPage r$)w7Gk<
* The everyPage to set. ">?vir^
*/ <\?wAjc,
publicvoid setEveryPage(int everyPage){ h gJ[LU| >
this.everyPage = everyPage; (sWLhUgRX
} G[jW<'f
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/** \"hJCP?,
* @return A!^q
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* Returns the hasNextPage. V|\7')Qq
*/ qZ@s#UiB
publicboolean getHasNextPage(){ w3jO6*_ M
return hasNextPage; vq34/c^
} =B.F;40
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/** }@.|?2b +
* @param hasNextPage FLEo*9u>b
* The hasNextPage to set. ||yzt!n
*/ J90v!p-
publicvoid setHasNextPage(boolean hasNextPage){ 7gRgOzWfV
this.hasNextPage = hasNextPage; #Fyuf,hw4
} LdJYE;k Ju
! VjFW5'{
/** S*yjee<@
* @return BT}&Y6
* Returns the hasPrePage. eYx Kp!f
*/ tBpC: SG
publicboolean getHasPrePage(){ -_$$Te
return hasPrePage; (5\NB0
} 7g_]mG[6
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/** nB .G
* @param hasPrePage [=~ pe|8:
* The hasPrePage to set. vTn}*d.K=
*/ iYC9eEF
publicvoid setHasPrePage(boolean hasPrePage){ \l~*PG2
this.hasPrePage = hasPrePage; V^;jJ']
} s=CK~+,/
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/** %D * OO{
* @return Returns the totalPage. Dd`Mv$*d8
* &r:7g%{n
*/ /Z7iLq~t"G
publicint getTotalPage(){ }f2r!7:x
return totalPage; o=`C<}
} jlxpt)0i
2#k5+?-c61
/** AlJ} >u
* @param totalPage NVRLrJWpp
* The totalPage to set. u]OW8rc
*/ kZ"BBJ6w
publicvoid setTotalPage(int totalPage){ R
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this.totalPage = totalPage; B5$kHM%p
} itMg|%B%
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} g:EVhuK
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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 Pi|o` d
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个PageUtil,负责对Page对象进行构造: 64
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java代码: 8U_{|]M
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M9f35
:
/*Created on 2005-4-14*/ Dwzg/F(
package org.flyware.util.page; yq$,,#XDD=
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import org.apache.commons.logging.Log; Rn@#d}
import org.apache.commons.logging.LogFactory; A~mum+[5
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/** H*r>Y
* @author Joa 4"Hye&O
* Q`D_|L
*/ ~zw]5|
publicclass PageUtil { 9+pmS#>_
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privatestaticfinal Log logger = LogFactory.getLog Si~vDQ7"
~ar=PmYV7
(PageUtil.class); ]~3U
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/** 9H%X2#:fH
* Use the origin page to create a new page (P`3 @H
* @param page K^R,Iu/M
* @param totalRecords 'PP#^aI,
* @return ^4o;$u4R
*/ R=KQ
publicstatic Page createPage(Page page, int PsZ
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totalRecords){ FJd]D[h
return createPage(page.getEveryPage(), qcT'nZ:
,#8e_3Z$
page.getCurrentPage(), totalRecords); n..g~$k
} e$pMsw'MJ
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/** C$5[X7'
* the basic page utils not including exception %!1Q P[}K
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handler @62Mk},9 c
* @param everyPage l(Q?rwI8Y
* @param currentPage !3ctB3eJ
* @param totalRecords Exk\8,EGqS
* @return page $r3i2N-I
*/ F_4n^@M
publicstatic Page createPage(int everyPage, int ^k\e8F/
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currentPage, int totalRecords){ YtWJXkB
everyPage = getEveryPage(everyPage); ~#/hzS
currentPage = getCurrentPage(currentPage); C7O6qpO
int beginIndex = getBeginIndex(everyPage, 1w&!H]%{
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currentPage); b?'yAXk
int totalPage = getTotalPage(everyPage, +j4"!:N}B
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totalRecords); RZCq {|L
boolean hasNextPage = hasNextPage(currentPage, SZXY/~=h
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totalPage); NrJKbk^4u/
boolean hasPrePage = hasPrePage(currentPage); R`~z0d.
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returnnew Page(hasPrePage, hasNextPage, LA)[ip4
everyPage, totalPage, %?Ev|:i`@
currentPage, ~T89_L
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beginIndex); lMbAs.!
} %Ijj=wW
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privatestaticint getEveryPage(int everyPage){ D~\$~&_]=
return everyPage == 0 ? 10 : everyPage; c[ ]4n
} A\.GV1
'Un" rts
privatestaticint getCurrentPage(int currentPage){ )[|3ZP`
return currentPage == 0 ? 1 : currentPage; s4uhsJL V$
} k{Aj^O3gD
UMcgdJB
privatestaticint getBeginIndex(int everyPage, int z.I9wQ]X[
mOlI#5H
currentPage){ ze]h..,]K
return(currentPage - 1) * everyPage; yiA<,!;4P
} _:"<[ >9
,xx R\}
privatestaticint getTotalPage(int everyPage, int
D N*t~Z3[
eh5gjSqx
totalRecords){ 0p\@!Z H
int totalPage = 0; I2nhqJy^
I'0@viF"Nx
if(totalRecords % everyPage == 0) 9uQ 4u/F
totalPage = totalRecords / everyPage; IyLx0[:U
else @$+ecaVW
totalPage = totalRecords / everyPage + 1 ; UCClWr
Z LD}a:s
return totalPage; >:|q&|x-
} <|Pun8j
ez6EjUk
privatestaticboolean hasPrePage(int currentPage){ EB8\_]6XJ
return currentPage == 1 ? false : true; 1[vi.
} oTuOw|[
.?Gd'Lp
privatestaticboolean hasNextPage(int currentPage, #gcF"L||
mFZ?hOyP.
int totalPage){ ,5*eX
return currentPage == totalPage || totalPage == ~Wa6J4B{K
\<)9?M :
0 ? false : true; 4zo5}L`Y
} 6Avw-}.7>
E!P yL>){
y7i*s^ys{
} KPj\-g'A
=HlQ36;*
7fba-7-P
w2'f/
"PpN0Rr
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 CLJ;<
TBT:/Vfun
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 ={xE!"
oT>(V]*5
做法如下: Yn G_m]
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 2mGaD\?K
qCnZhJ
的信息,和一个结果集List: wGP;Vbk
java代码: 6Z%U`,S
sU{NHC)5
(X3Tav
/*Created on 2005-6-13*/ x"
L20}
package com.adt.bo; :FTMmW,>'
D
'Zt
import java.util.List; AQ[GO6$,%H
C
.~+*"Vw
import org.flyware.util.page.Page; % V8U(z
#Ibp(
/** 2P@sn!*{1
* @author Joa +P`*kj-P\
*/ Kiu_JzD
publicclass Result { 1jF`5k
PU1Qsb5
private Page page; trp0V4b8
]n~ilS.rkl
private List content; ~"kb7Fxp
Ot6aRk
/** pv Gf\pu
* The default constructor +y3%3EKs1~
*/ D5*q7A6
public Result(){ LB a[:j2
super(); 3 C<L
} cZ2kYn8
[CXrSST")E
/** ?3.b{Cq{-
* The constructor using fields /VN f{p
* ]33>m|?@
* @param page ?}U(3
* @param content lUvpszH=
*/ )j0TeE1R
public Result(Page page, List content){ In<n&ib
this.page = page; m~-K[+ya`D
this.content = content; m1Mt#@,$
} 1R1z
n' q4
/** k@3Q|na
* @return Returns the content.
7B\Vs-d
*/ I
,z3xU
publicList getContent(){ KQg]0y
d
return content; n4R(.N00
} O#S;q5L@
/! "|_W|n
/** 0,89H4
* @return Returns the page. f>UXD
*/ E(8*
pI
public Page getPage(){ m;GbLncA
return page; 8)10o,#L
} rFj-kojg
vPTM
/** |w<H!lGe!$
* @param content +oovx2r&
* The content to set. ~^r29'3
*/ =06gj)8
public void setContent(List content){ UVd 7 JGR
this.content = content; U<_3^
} =pS5uR~
5',8 ziJQ
/** )W;o<:x3
* @param page 4;0lvDD
* The page to set. 5n9B?T8C
*/ P'Ux%Q+B>
publicvoid setPage(Page page){ j)/nKh4O
this.page = page; H?&Mbw
d
} PE3vQH=t~
} <~n"m
@oV9)
<FcG
oGK
e}
P I^bc
"J[K 3
2. 编写业务逻辑接口,并实现它(UserManager, a!"$~y$*
$ us]35Z3
UserManagerImpl) "NXB$a!:
java代码: %'s>QF]'
D*gFV{Ws
;U.hxh;+
/*Created on 2005-7-15*/ d(:8M
package com.adt.service; 4,CXJ2
=WyZX 7@R
import net.sf.hibernate.HibernateException; LE9(fe) fe
ToXki,
import org.flyware.util.page.Page; MbZJ;,e?
DVB{2~7 4
import com.adt.bo.Result; $m].8?
HUv/ ~^<
/** C9n?@D;S
* @author Joa }%'?p<^M
*/ hRrn$BdLX
publicinterface UserManager { XINu=N(g
ZjQ
|Wx
public Result listUser(Page page)throws s'E2P[:
ND>r#(_\
HibernateException; LYz.Ci}
vdx0i&RiL
} QgU8s'e
\eT5flC
bzuEfFaL
]|zp0d=&o
QxVq^H
java代码: G
MX?
&eCa0s?mI
)4<__|52"1
/*Created on 2005-7-15*/ W&&;:Fr
package com.adt.service.impl; vd
0ljA
<`B,R*H{
import java.util.List; :D%"EJ
Lvq>v0|
import net.sf.hibernate.HibernateException; GT }F9F~
jV>raCK_
import org.flyware.util.page.Page; B8V>NvE~o
import org.flyware.util.page.PageUtil; 4E]l{"k<
aWWU4xe
import com.adt.bo.Result; 3=FZ9>by
import com.adt.dao.UserDAO; 7hlO#PYZ
import com.adt.exception.ObjectNotFoundException; Jq&uF*!
import com.adt.service.UserManager; i|w81p^o
9F)z4
/** J'SZ
* @author Joa u09:Z{tL;@
*/ Q<^Tl(`/N?
publicclass UserManagerImpl implements UserManager { nrxo&9[@n
0=* 8
private UserDAO userDAO; Ma.`A
U(Nu%
/** K9$>Yxe|
* @param userDAO The userDAO to set. fPn>v)lN{
*/ #sPHdz'3M
publicvoid setUserDAO(UserDAO userDAO){ %r%M lj:#
this.userDAO = userDAO; e;Ti&o}
} 2ORNi,_I
aY'C%^h]
/* (non-Javadoc) ]iN'x?Fo
* @see com.adt.service.UserManager#listUser :PIF07$xl
P9^-6;'Y
(org.flyware.util.page.Page) trPAYa}W
*/ FbaEB RM
public Result listUser(Page page)throws }=gx#
_=Z,E.EN
HibernateException, ObjectNotFoundException { Xjo5v*P u
int totalRecords = userDAO.getUserCount(); /'].lp
if(totalRecords == 0) ^)(bM$(`
throw new ObjectNotFoundException ~P8tUhffK
T>}5:,N~
("userNotExist"); L+Xc-uv["p
page = PageUtil.createPage(page, totalRecords); 5][Ztx
List users = userDAO.getUserByPage(page); 5R@
returnnew Result(page, users); \6E|pbJ}x
} !sDh4jQ`
/y _O4
} %{AO+u2i
01r 8$+
8$85^Of
zVXC1u9B
Ir`eL
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 xy5lE+E_U
,&jhlZ i
询,接下来编写UserDAO的代码: a`&f
3. UserDAO 和 UserDAOImpl: { /K.3
java代码: WN{ 9
:3XA!o&.T3
'(f&P=[b
/*Created on 2005-7-15*/ <3xyjX'NE
package com.adt.dao; x_|UPF
VL%UR{
import java.util.List; ~$iIVJ`
P3cR l']
import org.flyware.util.page.Page; _LMM,!f
LR.Hh
import net.sf.hibernate.HibernateException; TH; R
& -{DfNK c
/** ]h>_\9qO
* @author Joa L\)ZC
*/ ud xZ0
publicinterface UserDAO extends BaseDAO { ?nofUD.
?WF/|/
publicList getUserByName(String name)throws ]+|~cRQ9I
,TXTS*V?
HibernateException; #w,Dwy
7ePqmB<.
publicint getUserCount()throws HibernateException; 0vEoGgY0*:
q*\x0"mS/
publicList getUserByPage(Page page)throws p<TpK )
?]Pmxp
H}
HibernateException; CN#+U,NZV
lsNrAA%m
} {;N,t]>8M
FME3sa$
^* J2'X38I
:"=ez<t
i=i(%yQ%
java代码: 9z}uc@#D=m
OK{quM5
q}~3C1
/*Created on 2005-7-15*/ ?&|5=>u2}$
package com.adt.dao.impl; q*F{/N**
dRj| g
import java.util.List; LV\DBDM
G B>QK
import org.flyware.util.page.Page; rs,2rSsg!
Qr^|:U!;[z
import net.sf.hibernate.HibernateException; O\E /. B
import net.sf.hibernate.Query; tE@;X=
Gnfd;.
(.
import com.adt.dao.UserDAO; 4US"hexE<
^cczJOxB
/** S{;sUGcu
* @author Joa Pl=ZRKn
*/ 1QLbf*zeIW
public class UserDAOImpl extends BaseDAOHibernateImpl NWM8[dI
Svondc
4
implements UserDAO { uT}' Y)m
S/D^
/* (non-Javadoc) SS$[VV
* @see com.adt.dao.UserDAO#getUserByName '+osf'&
=R #Qx,
(java.lang.String) x|mqL-Q f
*/ IB[)TZ2m
publicList getUserByName(String name)throws wQe_vY
?YZ- P{rTS
HibernateException { Q^
pmQ
String querySentence = "FROM user in class W_kHj}dj,p
Ag&0wN+jTM
com.adt.po.User WHERE user.name=:name"; UD8op]>L
Query query = getSession().createQuery D@Vt^_
e6d<dXx
(querySentence); 5[A@gw0u
query.setParameter("name", name); # a<Gxj
return query.list(); c- }X_)U }
} 9\/xOwR
%]>KvoA
/* (non-Javadoc) oJ4AIQjB
* @see com.adt.dao.UserDAO#getUserCount() pL{U `5S
*/ SzjkI+-$:
publicint getUserCount()throws HibernateException { =K6($|'=
int count = 0; '=Rs/EDME
String querySentence = "SELECT count(*) FROM KU8Jbl*
Jh
]i]7r
user in class com.adt.po.User"; ~y/
nlb!
Query query = getSession().createQuery r7b1-
a'2$nbp}
(querySentence); .w0s%T,8}^
count = ((Integer)query.iterate().next ~g5[$r-u-u
n2oz"<?$S
()).intValue(); 4|CtRF<L
return count; w]]8dz
} jV4\A
=~=*&I4Dp
/* (non-Javadoc) y~F,0"N\r
* @see com.adt.dao.UserDAO#getUserByPage H^s<{E0<
b)=[1g/=L
(org.flyware.util.page.Page) 0a}u;gt,4w
*/ X4 A<[&F/
publicList getUserByPage(Page page)throws T[j#M+p
@JyK|.b#0
HibernateException { a=hxJ1O
String querySentence = "FROM user in class kic/*v\6@
(=* cK-3
com.adt.po.User"; ~v6OsH%vx
Query query = getSession().createQuery J2'Nd'
UFp,a0|
(querySentence); rvnT6Ve
query.setFirstResult(page.getBeginIndex()) A'jP7P
.setMaxResults(page.getEveryPage()); joiL{
return query.list(); 2oNk93D
} wid;8%m
e>(<eu~P
} TWQG591
f!!V${)X
X@K-^8
E0MGRI"me
_nbBIaHN{
至此,一个完整的分页程序完成。前台的只需要调用 `C$:Yf]%nG
f;1K5Y
userManager.listUser(page)即可得到一个Page对象和结果集对象
@I_8T$N=
=8; {\
的综合体,而传入的参数page对象则可以由前台传入,如果用 aC%m- m
uF1~FKB
webwork,甚至可以直接在配置文件中指定。 D"ND+*Q[X
b\-&sM(W"
下面给出一个webwork调用示例: f]JM /
java代码: K }Vv4x1U
rL+!tH
]3KhgK%c8
/*Created on 2005-6-17*/ CS==A57I
package com.adt.action.user; li0i"
]>~)<
import java.util.List; eS<lwA_
@8;W \L$~1
import org.apache.commons.logging.Log; /J:bWr
import org.apache.commons.logging.LogFactory; BV>\ McI+
import org.flyware.util.page.Page; $!8-? ?ML
PDrZY.-
import com.adt.bo.Result; =gJb^
Gx(w
import com.adt.service.UserService; ,'p2v)p^4
import com.opensymphony.xwork.Action; \H=&`?
!+L/Khw/C
/** iy 14mh\ ~
* @author Joa ?i06f,-
*/ `eIenA
publicclass ListUser implementsAction{ rmE" rf
@>E2?CV
privatestaticfinal Log logger = LogFactory.getLog 11<KpxKpk
-lhLA`6_R
(ListUser.class); nIU 6h
B:!W$<
private UserService userService; V{^!BBQ
V??dYB(
private Page page; u"d~!j1
AO=h
23ZI
privateList users; *T~Ve;3h;
}MHCd)78b
/* mw='dFt
* (non-Javadoc) $ep.-I>
* {|1Y:&M?
* @see com.opensymphony.xwork.Action#execute() .8y3O]
*/ lsy?Ac
publicString execute()throwsException{ GQ9\'z#+
Result result = userService.listUser(page); 7D!u1?]d{
page = result.getPage(); KN7n@$8YM
users = result.getContent(); %oq[,h
<X
return SUCCESS; Er+nk`UR_
} j4;0|zx-i
A9kzq_3
/** Zxbo^W[[
* @return Returns the page. #1c_ev H
*/ Vv8jEZ8
public Page getPage(){ V( -mD
return page; *{yK
8
} {6~l$
[]A%<EI7
/** |Tm!VFd
* @return Returns the users. FKT1fv[H
*/ H<}^'#"p
publicList getUsers(){ ;uW}`Q<
return users; tPGJ<30
} \l.-eu'O
vh*U]3@
/** 4qYUoCR&
* @param page U
)l,'y2
* The page to set. e{v=MxO=S
*/ Fm #w2o
publicvoid setPage(Page page){ .F(i/)vaq|
this.page = page; ^1L>l9F
} ])Qs {hs~s
|"9 #bU
/** i}o[- S4
* @param users ]@0NO;bK>F
* The users to set. 9$|Gfyv
*/ ]- 4QNc=
publicvoid setUsers(List users){
NsJ(`zk:
this.users = users; *0>mB
} .?!N^_ Ez3
V`7FKL@"
/** 6+KHQFb&N
* @param userService R#DwF,
* The userService to set. 5GPo*Qpl
*/ >$,y5 AJ&
publicvoid setUserService(UserService userService){ hDp6YV,q
this.userService = userService; N~NQ6:R[
} =?s3iP
} Jte#ZnP
vMs$ceq
'8T=~R6
ty*@7g0k
}-o{ASC#
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, y:h}z).
hweaGL t0
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 ZJ 77[
lME)?LOI
么只需要: /M*a,o
java代码: zdEPDdB
p$x{yz3
" $ew~;z
<?xml version="1.0"?> Iz{R}#8CZ
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork sPb=82~z
`QUy;%+
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ?w+Ix~k
Z t&6Ua[Y}
1.0.dtd"> @bnG:np
!DI{:I_h(
<xwork> z ly unJD(
\a=D
<package name="user" extends="webwork- DVkB$2]
FA}_(Hf.[
interceptors"> .LuB\o$
QEu=-7@>
<!-- The default interceptor stack name !grVR157P
yin'vgQ
--> ^-a8V'
<default-interceptor-ref E gDQ+(
-
WzI8_uM
name="myDefaultWebStack"/> ^_%kE%I
.]9c /
<action name="listUser" if]Noe
cn-
nj]
class="com.adt.action.user.ListUser"> k~|-gfFP
<param D Kw*~0
(} 5S
name="page.everyPage">10</param> h#hxOVl%x
<result 5 XA=G
I6s3+x;O
name="success">/user/user_list.jsp</result> 5&e<#"
</action> mnID3=JF
Y2[A2Uy$ef
</package> ZDC9oX @
bI y sl
</xwork> >R2SQA o
((^sDE6(
JMS(9>+TA
s-7RW
N*@aDM07
d.2mT?`#
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 v i)%$~
PccB]
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。 nWvuaQ0}
V&|!RxWK
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 IB`>'~s&A
"aFhkPdWn
LsM7hLy
6y5A"-
thqS*I'#g
我写的一个用于分页的类,用了泛型了,hoho +~ #U7xgq/
R+~cl;#G6
java代码: %,iIpYx
07/L}b`P
>2?aZ`r+
package com.intokr.util; !8@*F
a@pz*e
import java.util.List; ~kCwJ<E
&
``d
/** l6u&5[C
* 用于分页的类<br> _NcYI
* 可以用于传递查询的结果也可以用于传送查询的参数<br> oiH|uIsqR
* WpLZQ6wH
* @version 0.01 [,aqQ6S
* @author cheng JNFIT;L
*/ BvU"4d;x
public class Paginator<E> { j2Pn<0U
privateint count = 0; // 总记录数 1'4J[S\cM
privateint p = 1; // 页编号 =5sF"L;b
privateint num = 20; // 每页的记录数 %G@5!|J
privateList<E> results = null; // 结果 6st^4S5
NA.1QQ;e
/** 6UE(f@
* 结果总数 CZEW-PIhj
*/ ItX5JV)
publicint getCount(){ (#oycj^<
return count; ;_:Oo l,
} yxBUj*3
Q#Y k?Kv~
publicvoid setCount(int count){ WM)F0@"
this.count = count; F#{gfh
} (Bo bB]~a
;p ]y)3
/** w&BGJYI
* 本结果所在的页码,从1开始 E&B{5/rv
* to6;?uC+|i
* @return Returns the pageNo. z\/53Sy<
*/ 6TH!vuQ1(
publicint getP(){ .]|Zf!>}s
return p; 4q$H
} Uw<&Wm`'
G]Jz"xH#
/** ~B$b)`*
* if(p<=0) p=1 Y1dVM]l
* "*7C`y5&P
* @param p 1>r ,vD&
*/ gq5qRi`q
publicvoid setP(int p){ $A$@|]}p
if(p <= 0) 1IgHc.s
p = 1; t?^9HP1b_
this.p = p; M_``'gw
} { ?{U,&
2BzqY`O
/** $cVi;2$p
* 每页记录数量 @1R8-aa-r
*/ ]Fb0Az
publicint getNum(){ Vdn.)ir~P
return num; 9zgNjjCl]
} Z v0C@r
P=H+ #
/** o7+>G~i
* if(num<1) num=1 Q&M'=+T
*/ /9Ilo\MdD
publicvoid setNum(int num){ J`#`fX
if(num < 1) 3hq1yyec
num = 1; ~k'V*ERNSj
this.num = num; >m_v5K
} dZ:r&Qa
c#b:3dXx9
/** tk/`%Q
* 获得总页数 Y~n`~(
*/ fn9#>~vrD
publicint getPageNum(){ s%;<O:x8o
return(count - 1) / num + 1; :G)<}j"sM
} 83.E0@$
w5]l1}rl
/** :k46S<RE
* 获得本页的开始编号,为 (p-1)*num+1 %d: A`7x
*/ A2x;fgi
publicint getStart(){ |)@N-f:E
return(p - 1) * num + 1; -PAF p3w\y
} FoPginZ]J
J?P]EQU
/** |t\|:E>" }
* @return Returns the results. uC~g#[I QM
*/ .9LL+d
publicList<E> getResults(){ Vos?PqUi 4
return results; ykq'g|
} .V%*{eHLL
>kdM:MK
public void setResults(List<E> results){ OR+A_:c.D
this.results = results; C]`eH*z~8
} /hdf{4
v5T9Y-{`
public String toString(){ J-J3=JG
StringBuilder buff = new StringBuilder T{*^_
1a9w(X
(); MB:n~>ga
buff.append("{"); M@?"t_e1
buff.append("count:").append(count); Q:S\0cI0
buff.append(",p:").append(p); )-&nxOP
buff.append(",nump:").append(num); >,h1N$A+
buff.append(",results:").append s?O&ZB2GM[
b?kPN:U#N/
(results); ]5|z3<K^
buff.append("}"); Goj4`Hc
return buff.toString(); j$eCe<.3
} |*Ot/TvG
7dD.G/'
} Xyv8LB
K="I<bK
'7nJb6V,0l