Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 L{(r@Vu
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 F3 wRHq
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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 %zX'u.}8#
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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 6bqJM#y@
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。 2|Tt3/Rn
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分页支持类: h8S%Q|-
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java代码: 0BE%~W
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package com.javaeye.common.util; +mxs jcq0
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import java.util.List; GWP"i77y0s
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publicclass PaginationSupport { O4-UVxv}
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publicfinalstaticint PAGESIZE = 30; -j<UhW
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privateint pageSize = PAGESIZE; [
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privateList items; |,yS>kjp
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privateint totalCount; blp )a
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privateint[] indexes = newint[0]; /M'b137
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privateint startIndex = 0; >EMCG.**
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public PaginationSupport(List items, int mexI}
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totalCount){ 4NEk#n
setPageSize(PAGESIZE); dxASU|Yo9
setTotalCount(totalCount); TyK;
q{
setItems(items); 6J=~ *&
setStartIndex(0); fA+M/}=
} j*6!7u.,K
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public PaginationSupport(List items, int ]|732Z
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totalCount, int startIndex){ 4CN8>J'-
setPageSize(PAGESIZE); ~ 4&_$e!
setTotalCount(totalCount); C g&1
setItems(items); wOa_"
setStartIndex(startIndex); ,*C^ixNE
} q].C>R*ux8
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public PaginationSupport(List items, int 1L$u8P^<
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totalCount, int pageSize, int startIndex){ ]=_BK!O
setPageSize(pageSize); ,fYO>l';`f
setTotalCount(totalCount); f0hi70\(X
setItems(items); m7 !l3W2
setStartIndex(startIndex); 7l:H~"9r
} DPe`C%Oc1
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publicList getItems(){ (+Uo;)~!YC
return items;
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} C8n1j2G\
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publicvoid setItems(List items){ -R\}Q"
this.items = items; )s^XVs.-
} !$d:k|b
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publicint getPageSize(){ {'X "9@
return pageSize; 1r.q]^Pq~
} As>po+T*
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publicvoid setPageSize(int pageSize){ * }2o
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this.pageSize = pageSize; K:9.fTCs*
} 2.:b
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publicint getTotalCount(){ IjrTM{f
return totalCount; |L+GM"hg
} 54 8@._-S
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publicvoid setTotalCount(int totalCount){ *&AK.n_
if(totalCount > 0){ 1w5p*U0 ;
this.totalCount = totalCount; h{TnvI/"
int count = totalCount / zd;xbH//)b
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pageSize; ll5Kd=3
if(totalCount % pageSize > 0) mV'd9(s?
count++; SD697L9
indexes = newint[count]; 8)H"w$jq
for(int i = 0; i < count; i++){ JUXK}0d%eN
indexes = pageSize * =RV$8.Xp
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} @D7cv"
}else{ DSIa3!0
this.totalCount = 0; dA_s7),
} Vj:PNt[
} g xLA1]>{
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publicint[] getIndexes(){ p~e6ah?1
return indexes; "w7:{E5e
} \K)q$E<!
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publicvoid setIndexes(int[] indexes){ lOEbh
this.indexes = indexes; u{_T,k<!
} iE&`Fhf?
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publicint getStartIndex(){ W:tE ?Hu
return startIndex; K1C#
} a-kU?&*
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publicvoid setStartIndex(int startIndex){ Db3tI#
if(totalCount <= 0) ciXAyT cG
this.startIndex = 0; JY_' d,O
elseif(startIndex >= totalCount) I)sCWC:Mq~
this.startIndex = indexes y%T'e(5Ed
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[indexes.length - 1]; jy1*E3vQ
elseif(startIndex < 0) *D9QwQ
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this.startIndex = 0; H-S28%.
else{ t;?
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this.startIndex = indexes \dCdyl6V
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[startIndex / pageSize]; a(<nk5
} _Fer-nQ2R
} d:j$!@o
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publicint getNextIndex(){ AAs&wYp8Yh
int nextIndex = getStartIndex() + ~+|p.(I
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pageSize; %f^TZ,q$
if(nextIndex >= totalCount) |M+ !O93
return getStartIndex(); .E@yB`AR
else l~\'Z2op
return nextIndex; UZdpKi@
} 8ayB<b>+]"
/*8"S mte
publicint getPreviousIndex(){ GHaD32
int previousIndex = getStartIndex() - x2%xrlv<J/
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pageSize; nc4KeEl
if(previousIndex < 0) (kCzz-_\
return0; w&8N6gA14
else .hPk}B/KV
return previousIndex;
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} Bi:%}8STH
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} J2W#vFe\
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抽象业务类 ' d' Dlg
java代码: 0@7%
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/** {wA(%e3_
* Created on 2005-7-12 EX@wenR
*/ @
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package com.javaeye.common.business; R2,Z`I
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import java.io.Serializable; /u?ZwoTzY
import java.util.List; FabgJu
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import org.hibernate.Criteria; uW;[FTcqy$
import org.hibernate.HibernateException; 2 8>
import org.hibernate.Session; uC$!|I
import org.hibernate.criterion.DetachedCriteria; lZ gX{
import org.hibernate.criterion.Projections; Z{XF!pS%H
import Wz{,N07Q#{
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org.springframework.orm.hibernate3.HibernateCallback; %j $r"
import H.o=4[
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org.springframework.orm.hibernate3.support.HibernateDaoS ZQ1,6<^9i[
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upport; =Vie0TV&h
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import com.javaeye.common.util.PaginationSupport; |!m8JV|x
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public abstract class AbstractManager extends |-l9 Z
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HibernateDaoSupport { 3R>"X c
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privateboolean cacheQueries = false; 5FMe &
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privateString queryCacheRegion; zQ~N(Jj?h
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publicvoid setCacheQueries(boolean He9Er
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cacheQueries){ KOhK#t>H@0
this.cacheQueries = cacheQueries; &v)/mc7D
} L/ g8@G
;
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publicvoid setQueryCacheRegion(String `(uN_zvH
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queryCacheRegion){ DFMf"_p
this.queryCacheRegion = Xl,707
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queryCacheRegion; GLp~SeF#
} Cu!S|Xj.
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publicvoid save(finalObject entity){ a)S{9q}%
getHibernateTemplate().save(entity); J?Bj=b
} dvcLZK
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publicvoid persist(finalObject entity){ a! 3e Z,
getHibernateTemplate().save(entity); zDf96eK
} "cwvx8un
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publicvoid update(finalObject entity){ ]T=o >%
getHibernateTemplate().update(entity); T@xaa\bzg
} 5cj&D74o
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publicvoid delete(finalObject entity){ 2)Q%lEm`SP
getHibernateTemplate().delete(entity); 4axuE]
} Tmk'rOg5
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publicObject load(finalClass entity, >~O/ZDu/@
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finalSerializable id){ !{F\\D/
return getHibernateTemplate().load Ip0`R+8
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(entity, id); 06 an(&a9
} )TcD-Jr
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publicObject get(finalClass entity, J ql$
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finalSerializable id){ iow"X6_l_
return getHibernateTemplate().get )_kU,RvZ
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(entity, id); WM0-F@_
} %<>|cO
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publicList findAll(finalClass entity){ /tJ%gF
return getHibernateTemplate().find("from #[]B:
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" + entity.getName()); MFz6y":~
} u)~::2BXAn
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publicList findByNamedQuery(finalString gWl49'S>+
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namedQuery){ ynn>d
return getHibernateTemplate t;
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().findByNamedQuery(namedQuery); b~;M&Y
} +hIMfhF
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publicList findByNamedQuery(finalString query, vv D515i
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finalObject parameter){ p@3 <{kLm
return getHibernateTemplate $*7AG
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().findByNamedQuery(query, parameter); #&Zj6en}M]
} ei
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publicList findByNamedQuery(finalString query, `8D'r|=`Eh
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finalObject[] parameters){ w"!zLB&9[
return getHibernateTemplate Lmc"qFzK
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().findByNamedQuery(query, parameters); ~./M5P!\
} @}tk/7-E
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publicList find(finalString query){ 41o~5:&
return getHibernateTemplate().find /&RS+By(i
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(query); ETaLE[T%1
} *%QTv3{
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publicList find(finalString query, finalObject #po}Y
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parameter){ vH vwH
return getHibernateTemplate().find mTZgvPJ!
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(query, parameter); E"b"VB
} H_7X%TvXb
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public PaginationSupport findPageByCriteria I
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(final DetachedCriteria detachedCriteria){ _tg&_P+kV
return findPageByCriteria MU^7(s="
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); K bY5
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} K>TdN+Z}=
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public PaginationSupport findPageByCriteria rZDlPp>BPZ
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(final DetachedCriteria detachedCriteria, finalint @t
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startIndex){ lbv9 kk[
return findPageByCriteria Y)>GwFK$
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(detachedCriteria, PaginationSupport.PAGESIZE, eyZ /%4'q
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startIndex); Elt=/,v`!
} JBCcR,\kM*
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public PaginationSupport findPageByCriteria {ZH9W
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(final DetachedCriteria detachedCriteria, finalint pC2r{-
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pageSize, 0)V<)"i
finalint startIndex){
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return(PaginationSupport) ldo7}<s
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getHibernateTemplate().execute(new HibernateCallback(){ 5uK:f\y)l
publicObject doInHibernate vMXS%Q
}Lx?RU+@=
(Session session)throws HibernateException { J 21D/#v
Criteria criteria = XQhBnam%
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detachedCriteria.getExecutableCriteria(session); #5kQn>R
int totalCount = |2\6X's
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((Integer) criteria.setProjection(Projections.rowCount a[:0<Ek
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()).uniqueResult()).intValue(); /lSz8h2
criteria.setProjection -y{o@
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(null); qWf7k+7G
List items = K+D`U6&
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criteria.setFirstResult(startIndex).setMaxResults I=wP"(2
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(pageSize).list(); #J]u3*Tn|
PaginationSupport ps = ]&1Kz
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new PaginationSupport(items, totalCount, pageSize, \iAkF`OC
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startIndex); g*b`V{/Vw
return ps; ?yF)tF+<
} wAxXK94#3
}, true); nZa.3/7dJ
} z!5^UD8"W
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public List findAllByCriteria(final k7Fa+Y)K7
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DetachedCriteria detachedCriteria){ 2H_|Attoi
return(List) getHibernateTemplate >[=q9k
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().execute(new HibernateCallback(){ 5 fjeBfy
publicObject doInHibernate yc2c{<Ya5
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(Session session)throws HibernateException { 7</&=lly
Criteria criteria = Z9s tB>?
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detachedCriteria.getExecutableCriteria(session); [K;J#0V+&L
return criteria.list(); >v @R]9
} wxXp(o(
}, true); S1{UVkr
} JS r& S[
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public int getCountByCriteria(final HcA;'L?Dw
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DetachedCriteria detachedCriteria){ )_OKw?Zi
Integer count = (Integer)
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getHibernateTemplate().execute(new HibernateCallback(){ F0%FX`b{{
publicObject doInHibernate 1`N q
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(Session session)throws HibernateException { (,`ypD +3q
Criteria criteria = m(E-?VMHo
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detachedCriteria.getExecutableCriteria(session); Ln0rm9FV-
return 2e zQX2q
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criteria.setProjection(Projections.rowCount <\GP\G
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()).uniqueResult(); LFob1HH*8
} Z:W6@j-~
}, true); *{8Kb>D
return count.intValue(); g4( B=G\j
} L8N`<a5T
} 6+(g4MW
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用户在web层构造查询条件detachedCriteria,和可选的 WY#A9i5Ge
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 Vu0jNKUV
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PaginationSupport的实例ps。 4G0Er?D
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ps.getItems()得到已分页好的结果集 bsy\L|wd
ps.getIndexes()得到分页索引的数组 tM]~^U
ps.getTotalCount()得到总结果数 pb1/HhRR^n
ps.getStartIndex()当前分页索引 TaeN?jc5
ps.getNextIndex()下一页索引 "Q6oPDX(
ps.getPreviousIndex()上一页索引 MZ
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 `P<}MeJ\l
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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 7N,E%$QL
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一下代码重构了。 T;qP"KWZ
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我把原本我的做法也提供出来供大家讨论吧: ?47q0C
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首先,为了实现分页查询,我封装了一个Page类: |oPCmsO3R{
java代码: J3gJSRT@P
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/*Created on 2005-4-14*/ 13wO6tS
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package org.flyware.util.page; [ZU6z?Pf
]3]I`e{
/** +<7~yZ[Z8
* @author Joa u )PB@
* #4iSQ$0
*/ ^JZ ]?iny
publicclass Page { @ofivCc<%
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/** imply if the page has previous page */ &?flH;
privateboolean hasPrePage; 3ha^NjE
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/** imply if the page has next page */ S[(Tpk2_
privateboolean hasNextPage; Z8*E-y0
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/** the number of every page */ P*Va<'{:{
privateint everyPage; Jt5\
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/** the total page number */ pA7&
privateint totalPage; UIgs/
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/** the number of current page */ 2\80S[f
privateint currentPage; ?aOx
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/** the begin index of the records by the current chk1tFV
_ K["qm{X_
query */ xR}^~14Bz
privateint beginIndex; U Hh
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/** The default constructor */ #v+2W
public Page(){ N\{Xhr7d
@v&hr
} OP0KK^#
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/** construct the page by everyPage ;:2]++G
* @param everyPage r(WR=D{
* */ +.^BM/z^O
public Page(int everyPage){ t4(Z@X$
this.everyPage = everyPage; o;5 J=
} [y$P'Y
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/** The whole constructor */ 2GeJ\1k
public Page(boolean hasPrePage, boolean hasNextPage, :}(Aq;}X
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int everyPage, int totalPage, Aiyx!Q6vT
int currentPage, int beginIndex){ :"QR;O@
this.hasPrePage = hasPrePage; yu3: Hv}
this.hasNextPage = hasNextPage; *|WS,
this.everyPage = everyPage; \Gm$hTvB&
this.totalPage = totalPage; Ok63 w7
this.currentPage = currentPage; qj|P0N{7
this.beginIndex = beginIndex; v$~1{}iI5
} ZNWo:N8;
*} @Y"y
/** Wk<he F
* @return +I~`Ob
* Returns the beginIndex. [ye!3h&]
*/ pY@$N&+W
publicint getBeginIndex(){ -u+@5K;^Y
return beginIndex; 2tPW1"M.n
} %-9?rOr
n!Hj4~T0
/** M~'4>h}
* @param beginIndex s4V-brCM$|
* The beginIndex to set. yC#%fgQ r
*/ HK}br!?
publicvoid setBeginIndex(int beginIndex){ 2S%[YR>>
this.beginIndex = beginIndex; |q|?y`X4/
} <46>v<
GZ=7)eJ~<
/** mQL8ec_c
* @return WXq=FZ-
* Returns the currentPage. }-` N^
*/ 1,Ams
publicint getCurrentPage(){ v=m!$~
return currentPage; @QOlo-u
} 1f}YKT
ZVu_E.4.
/** QjT$.pUd
* @param currentPage f6/<lS oW
* The currentPage to set. BQW hTS7
*/ yV"k:_O{
publicvoid setCurrentPage(int currentPage){ r_R(kns
this.currentPage = currentPage; xA7>";sla[
} (U_`Q1Jo
vbA<=V*P
/** Kd='l~rby
* @return "Y'MuV'x
* Returns the everyPage. 5;v_?M!UCK
*/ nR%ey"
publicint getEveryPage(){ J[|4`GT
return everyPage; &,DZ0xA
} dw*PjIB9x
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/** Tumv0=q4wd
* @param everyPage "mk@p=d
* The everyPage to set. DtEvt+h
*/ ]u5B]ZQnA
publicvoid setEveryPage(int everyPage){ 1`sLbPW
this.everyPage = everyPage; ztS:1\
} IL0e:-@!0
hw5NHZ I'
/** z:Y
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* @return ,r5'nDV=d
* Returns the hasNextPage. ,|}}Ml
*/ yN@3uYBF
publicboolean getHasNextPage(){ C4[) yJ
return hasNextPage; c/6
} ;{L ~|q J
8_W=)w6
/** 8(3nv[
* @param hasNextPage V><,.p8
* The hasNextPage to set. @5RbMf{
*/ )tvP|
publicvoid setHasNextPage(boolean hasNextPage){ :?!b\LJ2^
this.hasNextPage = hasNextPage; ?d!*[Ke8
} ?2(52?cJ
!+Fr U'^
/** Q6 oM$qiM
* @return 0-P,zkK_v
* Returns the hasPrePage. g)Tr#
*/
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publicboolean getHasPrePage(){ J#'8]p3E
return hasPrePage; }AW"2<@
}
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/** *SK`&V
* @param hasPrePage $,.XPK5Qu
* The hasPrePage to set. ]Y3NmL
*/ 11^.oa+`
publicvoid setHasPrePage(boolean hasPrePage){ mOC<a7#
this.hasPrePage = hasPrePage; 88 &M8T'AP
} +^<s'
H:#sf][&,L
/** !kxJ&VmeF
* @return Returns the totalPage. XN^l*Q?3n
* \Ota~A
*/ sRI0;
publicint getTotalPage(){ ^7Rc\
return totalPage; >d3`\(v-
} WR"?j9y_q
B"Ma<"HU
/** ey]WoUZ
* @param totalPage M!wa }
* The totalPage to set. 5La' I7q
*/ yE#.Q<4
publicvoid setTotalPage(int totalPage){ EJW}&e/
this.totalPage = totalPage; :Ahw{z`H#
} 9u;/l#?@T
aizJ&7(>
} 6}cN7wnm
j
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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 cC*H.N
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个PageUtil,负责对Page对象进行构造: ,p>@:C/M
java代码: %a:>3!
+
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/*Created on 2005-4-14*/ :w<Ga8\tZ
package org.flyware.util.page; |jB/d@RE
R=J5L36F
import org.apache.commons.logging.Log; @~QI3)=s
import org.apache.commons.logging.LogFactory; ?j;,:n
~f:"Q(f+
/** +>ld
* @author Joa {%oxzdPc
* DJZ$M
*/ sOO_J!bblP
publicclass PageUtil { "-Yj~
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privatestaticfinal Log logger = LogFactory.getLog QuIZpP=
hb<cynY
(PageUtil.class); $x*(D|\'<
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/** X7rsO^}W
* Use the origin page to create a new page J(:y-U
* @param page 90 >V he
* @param totalRecords 7NRm\%^q
* @return
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*/ \beYb0(+
publicstatic Page createPage(Page page, int VfFbZds8f
$H`{wJ?2(
totalRecords){ v~A*?WU;n
return createPage(page.getEveryPage(), &^7(?C'u
Qd/x{a8
page.getCurrentPage(), totalRecords); 4"pU\g
} u`;P^t5
d2?#&d'aq
/** !;U oZ~
* the basic page utils not including exception
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>qVSepK3
handler (<}BlL
* @param everyPage L6"V=^Bq
* @param currentPage kEp{L
* @param totalRecords j[A:So
* @return page [:zP]l.|
*/ ^'n;W<\p)
publicstatic Page createPage(int everyPage, int Q*hXFayx
"Hk7s+%
currentPage, int totalRecords){ SZUo RWx
everyPage = getEveryPage(everyPage); =6
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currentPage = getCurrentPage(currentPage); J|w%n5Y
int beginIndex = getBeginIndex(everyPage, 8O_yZ
~Z4
Us.k,
currentPage); Ae%AG@L
int totalPage = getTotalPage(everyPage, _\gCdNrD
]v]tBVO$
totalRecords); "d`u#YmR
boolean hasNextPage = hasNextPage(currentPage,
7&dK_x,a
6!se,SCvw
totalPage); -ykD/
boolean hasPrePage = hasPrePage(currentPage); *,zrg%8
e{H(
returnnew Page(hasPrePage, hasNextPage, n]6-`fpD
everyPage, totalPage, #-o 'g!
currentPage, /Pxny3
pekNBq
Wm
beginIndex); ?AH B\S
} l.P;85/+
IL1iTRH
privatestaticint getEveryPage(int everyPage){ 4hxa|f
return everyPage == 0 ? 10 : everyPage; iuA_Jr
} <I#M^}`
+`iJ+
privatestaticint getCurrentPage(int currentPage){ ((&5F!+\-
return currentPage == 0 ? 1 : currentPage; dUUg}/
} '
&3,qT
wD:2sri
privatestaticint getBeginIndex(int everyPage, int :cf#Tpq"
r@}8TE*|P
currentPage){ e<qfM&*
return(currentPage - 1) * everyPage; Ldj*{t`5
} xS:n
0cDP:EzR;
privatestaticint getTotalPage(int everyPage, int LpL$=9
fv@<
totalRecords){ /=T:W*C
int totalPage = 0; 7xFZJ#
lwz\"8
if(totalRecords % everyPage == 0) a;v4R[lQ
totalPage = totalRecords / everyPage; ;!C_}P
else +&dkJ 4g[
totalPage = totalRecords / everyPage + 1 ; h?H|)a<^9
$wn0oIuW
return totalPage; [k0/ZfFwV
} vvu $8n
tLxeq?Oo]
privatestaticboolean hasPrePage(int currentPage){ Wffz&pR8
return currentPage == 1 ? false : true; &E1m{gB(
} Y;'SD{On
xI.0m
privatestaticboolean hasNextPage(int currentPage, ~4|Tr z2T
l|{[vZpT
int totalPage){ nW}
s
return currentPage == totalPage || totalPage == xQ2:tY#?
CB
X}_]9X
0 ? false : true; 1+Uem
} 1J72*`4OK
S;y4Z:!
E [6:}z<
} 6^!fuIZ;_
C,A/29R,s
4UUbX
#a2gRg
@SyL1yFX
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 7xQ:[P!G+
hu1ZckIw?
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 rL&Mq}7QK
jEwt1S V
做法如下: c&x1aF "B
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 Br15S};Ce
z{FFTb^B
的信息,和一个结果集List: 2Y<]X7Ch:
java代码: FE]UqB
)0]U"Nf ho
UG=]8YY!
/*Created on 2005-6-13*/ |2%|=
package com.adt.bo; <5,|h3]-#
]31=8+D
import java.util.List; Y9>92#aME
'n
^,lXWB
import org.flyware.util.page.Page; =*I|z+
8]exsnZ
/** ,Si{]y
* @author Joa ~**x_ v
*/ K[
[6A:
publicclass Result { %q~q,=H$]
fm`V 2'Rm
private Page page; A)V*faD
01n132k
private List content; y4LUC;[n
ggiy{CdR
/** oP9 y@U
* The default constructor ?Pp*BB,*y
*/ IVkB)9IW
public Result(){ pf107S
super(); ]@b9m
} -B9e&J
{K
RRB=JP{r
/** G}^=(,jl
* The constructor using fields P"l'? `
* Je6wio-4
* @param page qT !lq
* @param content @4D{lb"{
*/ gBi3^GxjM?
public Result(Page page, List content){ mJ=V<_
this.page = page;
7s#8-i
this.content = content;
oI[rxr
} xVbRCu#Z
1:<(Q2X%
/** rhy-o?
* @return Returns the content. } `r.fD
*/ ]X77?Zz9
publicList getContent(){ N0-J=2
return content; N0Y4m_dm*
} 'QxJU$
7U_ob"`JV
/** VXWV Pj#
* @return Returns the page. ,LN^Zx*
*/ VQ|{Q}
public Page getPage(){ %),u0:go
return page; ;nP(S`'
} "n`z`{<n
}O>1tauI
/** `G/g/>y
* @param content [M,4qe8,}
* The content to set. `D
|/g;
*/ 77yYdil^W+
public void setContent(List content){ iiMS3ueF
this.content = content; )=d)j^t9
} 7xv9v1['
jhQoBC>:
/** =>`zk^
* @param page 'JJKnE zQ
* The page to set. ~{tO8
]
*/ |xcC'1WU
publicvoid setPage(Page page){ sdg2^] |
this.page = page; RuIBOo\XL7
} B K+P
} H.4ISmXU
?L7DVwVa,I
2=n`z)R
3PZ(Kn<
1h?ve,$
2. 编写业务逻辑接口,并实现它(UserManager, 1x;@BV
Ca5#'3Eh
UserManagerImpl) >Ti%Th,
java代码: J(d[05x0
Ih|4ISI
[)s4:V
/*Created on 2005-7-15*/ ~Yi4?B<
package com.adt.service; g^(gT
Wn+s:ov
import net.sf.hibernate.HibernateException; #eOHe4Vt
,^8':X"A{!
import org.flyware.util.page.Page; `1(ED= |
_Ffg"xoC
import com.adt.bo.Result; "WQ6[;&V
]zaTX?F:
/** IiqqdU]
* @author Joa ,o%by5j"^N
*/ V~j^
publicinterface UserManager { OxGfLeP.R!
>fI\f <ez
public Result listUser(Page page)throws UWC4PWL,>C
YR-G:-(#b
HibernateException; h`\$8oV
UHvA43
} lWj*tnnn[
7)jN:+4N
6[k<&;
TS9<uRO0
(LmU\ Pe%
java代码: cYK:Y!|`F
F&R*njJcc
M-i3_H)
/*Created on 2005-7-15*/ 9X 4[Zk
package com.adt.service.impl; @ewaj!
yP+<kv4
import java.util.List; <ytzGDx
zhs@YMY
import net.sf.hibernate.HibernateException; \^"Vqx
F<g&t|@
import org.flyware.util.page.Page; 6c-3+,Y"#
import org.flyware.util.page.PageUtil; ?[zw5fUDS
AF"7 _
import com.adt.bo.Result; 6_KvS
import com.adt.dao.UserDAO; {:!>Y1w>
import com.adt.exception.ObjectNotFoundException; gR# k'
import com.adt.service.UserManager; M9R'ONYAa
Eqz|eS*6
/** (JlPe)Q5
* @author Joa ?SFQx\/
*/ ]b%U9hmL^f
publicclass UserManagerImpl implements UserManager { l $\2|D
v:4j3J$z
private UserDAO userDAO; IxCesh
d-1D:Hs?
/** Z3{1`"\<K
* @param userDAO The userDAO to set. XJeWhk3R9
*/ I*.nwV<
publicvoid setUserDAO(UserDAO userDAO){ :Q("
this.userDAO = userDAO; Ue9Y+'-x
} iKrk?B<
we`BqZV
/* (non-Javadoc) SXqB<j$.;
* @see com.adt.service.UserManager#listUser /i>n1>~yn
V /2NIh
(org.flyware.util.page.Page) '[liZCg
*/ J^jd@E
public Result listUser(Page page)throws ?s$d("~
GxD`M2
HibernateException, ObjectNotFoundException { #;ObugY,
int totalRecords = userDAO.getUserCount(); [%bGs1U
if(totalRecords == 0) %50)?J=zB
throw new ObjectNotFoundException K0j%\]\Tp
G4SA
u
("userNotExist"); G7" (,L` 5
page = PageUtil.createPage(page, totalRecords); stajTN*J
List users = userDAO.getUserByPage(page); N? Jy
returnnew Result(page, users); 3#t#NW*e
} EOu[X'gLr
) dk|S\
} 9!X3Cv|+L
uOzoE_i
G8+&fn6
G3^<l0?S
>eG<N@13p
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 v2rO>NY4
$aJ6i7C,j}
询,接下来编写UserDAO的代码: L$_%T
3. UserDAO 和 UserDAOImpl: <<?32r~
java代码: o=7,U/{D!
6ScB:8M
GB Yy^wjU
/*Created on 2005-7-15*/ ph5{i2U0
package com.adt.dao; N`efLOMl]
@!dIa1Q"
import java.util.List; *
rlVE
=9ff983
import org.flyware.util.page.Page; 4xg)e`
*U
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import net.sf.hibernate.HibernateException; X$6NJ(2G
2T+-[}*
/** e,}h^^"
* @author Joa `OMX 9i
*/ b;jdk w|
publicinterface UserDAO extends BaseDAO { $k0(iFzR1
H;\C7w|
publicList getUserByName(String name)throws q,)V0Ffe[|
V5ZC2H
HibernateException; k/{WlLN
7\%JJw6h
publicint getUserCount()throws HibernateException; 1Mp-)-e
qA)YYg/G
publicList getUserByPage(Page page)throws +U<YM94?
ow9a^|@a
HibernateException; 2k<#e2
8_4!Ar>2
} e%)iDt\j
_x(hlHFk
082iEG
dVB#Np
*KDTBd
java代码: LXX('d
HJ]v-
$]_SPu
/*Created on 2005-7-15*/ rwXpB<@l@
package com.adt.dao.impl; F\+AA
50Gr\
import java.util.List; '(B -{}l
~wuCa!!A
import org.flyware.util.page.Page; EQlb:;j
\54B
import net.sf.hibernate.HibernateException; &Iy5@8
import net.sf.hibernate.Query; 9pnOAM}
%Ve@DF8G
import com.adt.dao.UserDAO; o%~fJx:]y
N2s"$Ttq
/** lfDd%.:q4S
* @author Joa 6k;5T
*/ C5 ILVQ
public class UserDAOImpl extends BaseDAOHibernateImpl (n7xYGfYS
8%B_nVc
implements UserDAO { 9R8q+2
0,RYO :`
/* (non-Javadoc) 5@>hjXi"Y
* @see com.adt.dao.UserDAO#getUserByName ?[ )}N
_o#
r]cq|Nv8:
(java.lang.String) hOk9 y=
*/ ,e'm@d$Q*
publicList getUserByName(String name)throws z[J=WI
id9QfJ9t
HibernateException { G3TS?u8Q
String querySentence = "FROM user in class dT'}:2
*B!Ox}CI.L
com.adt.po.User WHERE user.name=:name"; w>f.@luO4
Query query = getSession().createQuery C <:g"F:k
lfM vNv
(querySentence); KDEyVYO:
query.setParameter("name", name); n~yHt/T
return query.list(); cy,6^d
}
n(Nu
:1 qLRr
/* (non-Javadoc) K!CVS7
* @see com.adt.dao.UserDAO#getUserCount() 5B:"$vC{=
*/ QEqYqAGzu|
publicint getUserCount()throws HibernateException { Mu`_^gG
int count = 0; TM6wjHFm
String querySentence = "SELECT count(*) FROM 3_
J'+
p3 5)K5V
user in class com.adt.po.User"; _@>*]g
Query query = getSession().createQuery j}.gK6Yq*
Uzvd*>mv
(querySentence); YQ:$m5ai
count = ((Integer)query.iterate().next j;}-x1R
s:6K'*
()).intValue(); jGo%Aase
return count; ! N2uJ?t
} ^}$t(t
>4wigc
/* (non-Javadoc)
iWjNK"W
* @see com.adt.dao.UserDAO#getUserByPage 'Iw`+=iVz
Y<W9LF
(org.flyware.util.page.Page) YM;ro5_KF
*/ &cyB}Gv
publicList getUserByPage(Page page)throws XuJyso9kA
geK;r0(f
HibernateException {
'v Vt^h2
String querySentence = "FROM user in class {'zS8
)XonFI
com.adt.po.User"; r&R~a9+)
Query query = getSession().createQuery )R
`d x
83vZRQw
(querySentence); .CEC
g*f
query.setFirstResult(page.getBeginIndex()) I_f%%N%
.setMaxResults(page.getEveryPage()); Zex~ $r
return query.list(); cG0)F%?X?
} ^NU_Tp:2^
\,NT5>
} ]p+KN>1e
-n"f>c_{>
aoW2 c1`?Z
3"Oipt+
STu(I\9
至此,一个完整的分页程序完成。前台的只需要调用 JzywSQ
}*!L~B!
userManager.listUser(page)即可得到一个Page对象和结果集对象 QyTNV
-ABj>y[
的综合体,而传入的参数page对象则可以由前台传入,如果用 U*K4qJ6U
)( 3)^/Xz
webwork,甚至可以直接在配置文件中指定。 t9<BQg
}!fIY7gv
下面给出一个webwork调用示例: a+z>pV|
java代码: p\_3g!G'
2|ee` "`
^~l@ _r
/*Created on 2005-6-17*/ [MAPa
package com.adt.action.user; %6lGRq{/?
uHquJQ4
import java.util.List; YYI0iM>
>,zU=I?9Y
import org.apache.commons.logging.Log; $Xo_8SX,
import org.apache.commons.logging.LogFactory; k"[AV2UW1
import org.flyware.util.page.Page; ,DHH5sDCn
4mW$+lzn
import com.adt.bo.Result; 81#x/&E]
import com.adt.service.UserService; pR0!bgC
import com.opensymphony.xwork.Action; > Q=e9L=
u=@zYA(
/** ]2"UR_x
* @author Joa $U ._4
*/ B_Gcz5
publicclass ListUser implementsAction{ fGj66rMGw
Se[=$W
privatestaticfinal Log logger = LogFactory.getLog [%LGiCU]
`@\FpV[|P
(ListUser.class); ?-&k?I
?7CdJgJp
private UserService userService; 2vUcSKG7
D3g5#.$,}>
private Page page; +-t&li%F
(Q `Ps/
privateList users; x^[0UA]S9
!|VtI$I>x
/* ~^Al#@
* (non-Javadoc) s$f9?(,.Ay
* se3EI1e
* @see com.opensymphony.xwork.Action#execute() ec^{ez@`
*/ y<IHZq`C3
publicString execute()throwsException{ L6qK3xa}
Result result = userService.listUser(page); L1lDDS#
page = result.getPage(); .I{u[
"
users = result.getContent(); K
..Pn17t
return SUCCESS; l8M}82_
} dcemF
7{"F%`7L
/** Z{ YuX
* @return Returns the page. K7x;/O
*/ Pj56,qd>s
public Page getPage(){ -
]We|{
return page; }n^}%GB
} _,F\%}
`mZ1!I-T
/** -H\j-k
* @return Returns the users. t,w/L*r+w
*/ ~PpU'[
publicList getUsers(){ dEf5x_TGm
return users; ~nj+"d]
} g~|x^d^;|
=<M>fJ)
/** o}wRgG
* @param page [D?xd/G
* The page to set. %PR,TWe
*/ e7Gb7c~
publicvoid setPage(Page page){ D ][I#vh
this.page = page; fe6Op
} D@{m
d`?EEO
/** $WE_aNfja
* @param users %0815
5M
* The users to set. zuJ` 704
*/ GXv2B%i8
publicvoid setUsers(List users){ h52+f
this.users = users; Pa; *%7
} Cx) N;x
h4slQq~K
/** )=N.z6?
* @param userService h_Er$ZT64
* The userService to set. >9g^-~X;v
*/ E/% F0\B
publicvoid setUserService(UserService userService){ I2z7}*<u
this.userService = userService; Br$/hn=
} '/ueY#eG
} +~
S7]AZ
|CS&H2!s
zZ<~yi3A9
*D7oHwDU
D*HK[_5
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, )B@&q.2B=
N0
t26| A
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 (hY^E(D
Jju?v2y`
么只需要: 5(\[Gke
java代码: lm'.G99{
?K.!^G
1Ji"z>H*
<?xml version="1.0"?> at3YL[,[Z
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork Uzn
,5sv;
1.0//EN" "http://www.opensymphony.com/xwork/xwork- w6B`_Z'f
!wrAD"l*@
1.0.dtd"> 9I|Q`j?p`
{#{nU NW
<xwork> Oo\~'I
giN(wPgYP
<package name="user" extends="webwork- LR17ilaa'
+hWeN&A
interceptors"> [9p@uRE
mL,{ZL ^
<!-- The default interceptor stack name l4^8$@;s
,6U=F#z
--> hn/SS
<default-interceptor-ref Qbj:^{`>(
P6tJo{l8w
name="myDefaultWebStack"/> I|mxyyf
k"FY
&;G(G
<action name="listUser" Lr>4~1:`
{
lZ<'p
class="com.adt.action.user.ListUser"> 1T3YFt@&I
<param )T^aJ-Uf
0ENqK2
name="page.everyPage">10</param> A kqGk5e
^
<result afcyAzIB&
AqrK==0N
name="success">/user/user_list.jsp</result> k.F(*kh
</action> klj.\wg/p{
Au?(_*/0
</package> Yr:$)ap
*-_joAWTG
</xwork> IG@@CH
(b1rd
X`daaG_l
"w{,ndZ
`udZ =S"/L
3dI(gm6
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 PuU<
~/R}K g(
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。 nx4E}8!Lh
t== a(e
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 RQ51xTOL4]
'nqVcNgb
"}UYsXg
pvd9wKz
7m9T'
我写的一个用于分页的类,用了泛型了,hoho ngaQa-8w
),I7+rY
java代码: AzBpQb*
c6pGy%T-
S4X['0rX!
package com.intokr.util; 7otqGE\2
C)s*1@af
import java.util.List; s!BZrVM%I`
t+SLU6j,
/** v{>9&o.J
* 用于分页的类<br> TsZX'Yn
* 可以用于传递查询的结果也可以用于传送查询的参数<br> E@;v|Xc
* 1 ^=[k
* @version 0.01 4=n%<U`Z/
* @author cheng 27jZ~Bp$
*/ 0 :1ldU
4
public class Paginator<E> { 12%4>2}~>
privateint count = 0; // 总记录数 -
e"XEot~
privateint p = 1; // 页编号 1HNX6
privateint num = 20; // 每页的记录数 9]/ju
privateList<E> results = null; // 结果 15~+Ga4
r;aP`MVO<
/** &@xeWB
* 结果总数 vui{["
*/ wZUR
publicint getCount(){ l{x?i00tAS
return count; m4@w M?
} &($Zs'X
32V,25 (`5
publicvoid setCount(int count){ FwGMrJW
this.count = count; c'6$`nC
} p}swJ;S
NBZ>xp[U
/** jk}m
* 本结果所在的页码,从1开始 #8jH_bi
* >pl*2M&
* @return Returns the pageNo. oE4hGt5x{
*/ 7dU7cc
publicint getP(){ gb0ZGnI
return p; [?`c>
} <ByDT$E_
IN9o$CZ:
/** MRHkQE+K@8
* if(p<=0) p=1 P1l@K2r
* #[#dc]D
* @param p w]0jq
U6
*/ gBG.3\[
publicvoid setP(int p){ S\UM0G}v
if(p <= 0) +nslS:(
p = 1; I2=Kq{
this.p = p; R OQIw
} =<[ZFO~v
;EfMTI}6K
/** KPA5 X]
* 每页记录数量 MXhRnVz"W
*/ B1Iq:5nmoS
publicint getNum(){ {N,w5!cP
return num; uy;3s=03^
} D r $N{d
5OUe|mS
/** {\e wf_pFk
* if(num<1) num=1 g)iSC?H
*/ ]H[FZY
publicvoid setNum(int num){
r4qFEFV3%
if(num < 1) 8)k.lPoo.
num = 1; w,.Hdd6
this.num = num; T;< >"" T
} 93(
}a_: oR
/** m"vV=6m|\
* 获得总页数 [@/[#p
*/ {:enoV"
publicint getPageNum(){ 6A/|XwfE/v
return(count - 1) / num + 1; K~WwV8c9;
} Ja#idF[V
Z
[5HI;
/** n{Mj<\kL
* 获得本页的开始编号,为 (p-1)*num+1 (Qq$ql27
*/ Q\:'gx8`
publicint getStart(){ {w^flizY
return(p - 1) * num + 1; h OboM3_
} qwaw\vOA
4p~:(U[q
/** (<.1o_Q-LU
* @return Returns the results. +T^m
*/ WiviH#hF
publicList<E> getResults(){ Ahq^dx#o
return results; q#Qr@Jf
} GW{Nc!)
TniZ!ud
public void setResults(List<E> results){ Rb~Kyy$
this.results = results; =4MiV]
} FM7N|]
m
"=f*Lk@[
public String toString(){ D_9/|:N:
StringBuilder buff = new StringBuilder +V8yv-/{
3P6!j
(); "5jZS6A]
buff.append("{"); sinG $=
buff.append("count:").append(count); nhCB])u8l
buff.append(",p:").append(p); }u+R,@l/
buff.append(",nump:").append(num); *G~c6BZ
buff.append(",results:").append d*>M<6b-
z4J-qK~2
(results); |ns^'q
buff.append("}"); :({lXGc}4?
return buff.toString(); p-;]O~^
} %e1vq
$C)@GGY
} iQGoy@<R
cdIy[
1
xSOL4