Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 2?nEHIUT
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Q" G;L
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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 ;5tQV%V^Q
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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 N
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分页支持类: *h
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java代码: ;T :]?5W!
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package com.javaeye.common.util; 2" u,f
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import java.util.List; gX]ewbPDQ
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publicclass PaginationSupport { f~:wI9
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publicfinalstaticint PAGESIZE = 30; Z '~Ie~
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privateint pageSize = PAGESIZE; bD`h/jYv
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privateList items; ]cM,m2^2
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privateint totalCount; [LM9^*sG2V
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privateint[] indexes = newint[0]; ^&KpvQNW_
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privateint startIndex = 0; @a (-U.CZ
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public PaginationSupport(List items, int AP+%T
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totalCount){ Ch_eK^ g1
setPageSize(PAGESIZE); RMHJI6?LB
setTotalCount(totalCount); e2kW,JV/<$
setItems(items); kD}vK+
setStartIndex(0); RT<HiVr`
} >%LY0(hY3
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public PaginationSupport(List items, int )]C(NTfxg
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totalCount, int startIndex){ S]Ye`
setPageSize(PAGESIZE); 6&o?#l;|
setTotalCount(totalCount); *p0Kw>
setItems(items); Sym}#F\s
setStartIndex(startIndex); ]]P@*4!
} Id=V\'$o
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public PaginationSupport(List items, int PR7B
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totalCount, int pageSize, int startIndex){ 40G'3HOp
setPageSize(pageSize); !8&EkXTw,
setTotalCount(totalCount); |nBs(>b
setItems(items); m qwJya
setStartIndex(startIndex); Vwb_$Yi+]
} FuC\qF
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publicList getItems(){ \027>~u
{
return items; QUDpAW
} NAOCQDk{
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publicvoid setItems(List items){ iN_P25Z<r
this.items = items; /[!<rhY
} g(i8HU*{q
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publicint getPageSize(){ [eFJ+|U9
return pageSize; .DM-&P
} \h?6/@3ob
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publicvoid setPageSize(int pageSize){ l{*Ko~g
this.pageSize = pageSize; _*Ej3=u
} e.fxB
n=?wX#rEC#
publicint getTotalCount(){ *fz#B/_o
return totalCount; 10xza=a
} a(LtiO
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publicvoid setTotalCount(int totalCount){ BjGfUQ
if(totalCount > 0){ q:=jv6T#
this.totalCount = totalCount; Dus!Ki~8(t
int count = totalCount / 0lV;bVa%
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pageSize; HPg%v|
if(totalCount % pageSize > 0) \/b[V3<"
count++; F"1tPWn
indexes = newint[count]; N 1ydL
for(int i = 0; i < count; i++){ Z5
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indexes = pageSize * YFDOp*
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i; <s%Ft
}
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}else{ 8`6G_:&X
this.totalCount = 0; 2A:&Cqo
} WNt':w^_
} w[ $oH^7
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publicint[] getIndexes(){ 'Va<GHr>+
return indexes; .PV(MV
} _Tm]tlV
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publicvoid setIndexes(int[] indexes){ @v3)N[|d
this.indexes = indexes; z$Le,+
} vK`HgRQ(C
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publicint getStartIndex(){ {+GR/l\!#
return startIndex; EM`'=<)V
} LzDRy L
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publicvoid setStartIndex(int startIndex){ q|0l>DPRp
if(totalCount <= 0) K]uH7-YvL/
this.startIndex = 0; ZH*h1?\X
elseif(startIndex >= totalCount) zl|
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this.startIndex = indexes x6*y$D^B
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[indexes.length - 1]; n_:EWm$\
elseif(startIndex < 0) pe<T"[X
this.startIndex = 0; ]0BX5Z'
else{ R.DUfU"gp
this.startIndex = indexes \98N8p;,I
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[startIndex / pageSize]; o
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} gf?N(,
} i=1crJ:
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publicint getNextIndex(){ zR<fz
int nextIndex = getStartIndex() + R$66F>Jz^
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pageSize; c{ +bY.J
if(nextIndex >= totalCount) 8vtembna4
return getStartIndex(); ,LP^v'[V7
else \Rb:t}
return nextIndex; ^do6?e`?-
} >#'?}@FWQN
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publicint getPreviousIndex(){ C/H;|3.X
int previousIndex = getStartIndex() - bwcr/J(Nb
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pageSize; AJE$Z0{q
if(previousIndex < 0) w^("Pg`
return0; U=7nz|
else J#ClQ%
return previousIndex; 0TSB<,9a[
} #ti%hm
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} t%J1(H
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抽象业务类 SH#*Lc
java代码: -(>Ch>O
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/** 6GPI
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* Created on 2005-7-12 wW/q#kc
*/ Y/"t!
package com.javaeye.common.business; O|)b$H_
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import java.io.Serializable; 6/?onEL9_
import java.util.List; eB=&(ZT
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import org.hibernate.Criteria; %vm_v.Q4)
import org.hibernate.HibernateException; X,#~[%h$-=
import org.hibernate.Session; (vX<Bh
import org.hibernate.criterion.DetachedCriteria; vC`SD]
import org.hibernate.criterion.Projections; LkP
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import Xx%<rsA>F
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org.springframework.orm.hibernate3.HibernateCallback; S D{ )Sq
import DW78SoyedZ
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org.springframework.orm.hibernate3.support.HibernateDaoS Kd58'$
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upport; !lo
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import com.javaeye.common.util.PaginationSupport; EpyMc+.Ze'
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public abstract class AbstractManager extends Crg'AB?
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HibernateDaoSupport { xy4+
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privateboolean cacheQueries = false; K1BBCe
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privateString queryCacheRegion; '21gUYm
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publicvoid setCacheQueries(boolean T_=WX_h $
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cacheQueries){ 3Jt#
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this.cacheQueries = cacheQueries; vJ=Q{_D=\
} % @+j@i`&
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publicvoid setQueryCacheRegion(String 'L-DMNxBr
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queryCacheRegion){ {>9ED.t
this.queryCacheRegion = |3yG
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queryCacheRegion; <F;+A{M)
} `]XI Q\ *
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publicvoid save(finalObject entity){ qt*+ D
getHibernateTemplate().save(entity); X!/Sk1
} >5:O%zQ@
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publicvoid persist(finalObject entity){ :?BK A0E
getHibernateTemplate().save(entity); S\<i`q
} ^.\O)K {h
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publicvoid update(finalObject entity){ H?8'(
getHibernateTemplate().update(entity); (.V),NKG
} dXQ C}JA
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publicvoid delete(finalObject entity){ h]k$K
getHibernateTemplate().delete(entity); h_S>Q
} L YF|
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publicObject load(finalClass entity, %dg[ho
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finalSerializable id){ (IVhj^dQm
return getHibernateTemplate().load oD9n5/ozo
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(entity, id);
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} y32$b,%Xi,
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publicObject get(finalClass entity, L/exR6M7
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finalSerializable id){ ?_^{9q%9
return getHibernateTemplate().get Q
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(entity, id); B 5|\<CF
} }UB@FRPF
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publicList findAll(finalClass entity){ HNv~ZAzBG-
return getHibernateTemplate().find("from Cd"{7<OyM4
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" + entity.getName()); ]lBCK
} C`ky=
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publicList findByNamedQuery(finalString `(0B09~7
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namedQuery){ h )5S4)
return getHibernateTemplate &k%>u[Bo
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().findByNamedQuery(namedQuery); 3U+FXK#6
} E KV[cq
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publicList findByNamedQuery(finalString query, ~vt9?(h
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finalObject parameter){ %J^x `P
return getHibernateTemplate p\ ;|Z+0=
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().findByNamedQuery(query, parameter); k-=LD
} aW&)3C2-x
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publicList findByNamedQuery(finalString query, >a<1J(c
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finalObject[] parameters){ [A!w
return getHibernateTemplate @|DQZt
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().findByNamedQuery(query, parameters); .Lna\Bv
} pLtw|S'4
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publicList find(finalString query){ E6 -*2U)k+
return getHibernateTemplate().find q -8G
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(query); @CmKF
} !EhKg)y=
@
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publicList find(finalString query, finalObject ngl +`|u
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parameter){ Pa{
return getHibernateTemplate().find f(Of+>
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(query, parameter); Wq1 jTIQ
} 6~x'~T
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public PaginationSupport findPageByCriteria KddCR&
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(final DetachedCriteria detachedCriteria){ ^x: lB>
return findPageByCriteria C'#)mo_@t
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(detachedCriteria, PaginationSupport.PAGESIZE, 0);
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} lFyDH{!
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public PaginationSupport findPageByCriteria Oti*"dV\::
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(final DetachedCriteria detachedCriteria, finalint j,+]tHC-
]$[sfPKA
startIndex){ *kl :/#
return findPageByCriteria $}gMJG
k_=yb^6[U
(detachedCriteria, PaginationSupport.PAGESIZE, jfY7ich
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startIndex); r@{TN6U
} !ka* rd
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public PaginationSupport findPageByCriteria 3uqhYT;
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(final DetachedCriteria detachedCriteria, finalint Lz'VQO1U=
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pageSize, QS&B"7;g
finalint startIndex){ rTIu'
return(PaginationSupport) 6(f'P_*
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getHibernateTemplate().execute(new HibernateCallback(){ LZRg%3.E
publicObject doInHibernate xf]K
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(Session session)throws HibernateException { ;mG*Rad
Criteria criteria =
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detachedCriteria.getExecutableCriteria(session); #_wq#rF
int totalCount = $ s/E}X
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((Integer) criteria.setProjection(Projections.rowCount 9qB0F_xl
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()).uniqueResult()).intValue(); S%i^`_=Q
criteria.setProjection ZNX38<3h
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(null); |1~n<=`Z
List items = 'p&,'+x
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criteria.setFirstResult(startIndex).setMaxResults 6:7[>|okQ
;=ddv@
(pageSize).list(); ,_Z(!|
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PaginationSupport ps = /uwi$~Ed
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new PaginationSupport(items, totalCount, pageSize, J~k9jeq9
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startIndex); v3I^81
return ps; ,yYcjs!=o
} 4N,mcV
}, true); y>P+"Z.K%}
} $oK&k}Q
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public List findAllByCriteria(final !qt2,V
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DetachedCriteria detachedCriteria){ mH'~pR>t
return(List) getHibernateTemplate 8b2 =n
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().execute(new HibernateCallback(){ 6Yj{%
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publicObject doInHibernate lM6pYYEq=
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(Session session)throws HibernateException { ai{>rO3 }I
Criteria criteria = l#'V
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detachedCriteria.getExecutableCriteria(session); #Vq9 =Q2
return criteria.list(); :aesG7=O
} E#B-JLMGl
}, true); }Y~Dk]*
} Lnr9*dm6q
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public int getCountByCriteria(final J7`mEL>?
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DetachedCriteria detachedCriteria){ [0 F~e
Integer count = (Integer) $.SBW=^V
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getHibernateTemplate().execute(new HibernateCallback(){ Jj"{C]
publicObject doInHibernate H3A$YkK [
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(Session session)throws HibernateException { #Iw(+%D
Criteria criteria = $Habhw
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detachedCriteria.getExecutableCriteria(session); w&p+mJL.
return 3
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criteria.setProjection(Projections.rowCount [n2B6Px
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()).uniqueResult(); B>,eHXW
} EuK}L[Kl
}, true); b3ohTmy4(
return count.intValue(); YV
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} m ptFd
} #De>EQ%
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用户在web层构造查询条件detachedCriteria,和可选的 f[@96p?a[
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 )9]a
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PaginationSupport的实例ps。 [C'bfX5HB5
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ps.getItems()得到已分页好的结果集 p5G'})x
ps.getIndexes()得到分页索引的数组 jm}CrqU
ps.getTotalCount()得到总结果数 QJ|@Y(KV0
ps.getStartIndex()当前分页索引 Ipp_}tl_
ps.getNextIndex()下一页索引 R'>!1\?Iq
ps.getPreviousIndex()上一页索引 T+kV~ w{
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 %5o2I_Cjz
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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 <!OBpAq
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一下代码重构了。 ^/f~\#R
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我把原本我的做法也提供出来供大家讨论吧: PTQ#8(_,
Ds9)e&yYrb
首先,为了实现分页查询,我封装了一个Page类: ` 2lS@
java代码: n6/Ous
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/*Created on 2005-4-14*/ kp m;ohd
package org.flyware.util.page; >Bt82ibN
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/** NkZG
* @author Joa bZqTT~'T
* J=g)rd[`
*/ O2w-nd74U
publicclass Page { eV9U+]C`
pv_o4qEN
/** imply if the page has previous page */ 3:J>-MO
privateboolean hasPrePage; AGlBvRX7e
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/** imply if the page has next page */ ^HKXm#vAB
privateboolean hasNextPage; oaIk1U;g
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/** the number of every page */ '6so(>|
privateint everyPage; t R^f]+Up
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/** the total page number */ x~5uc$
privateint totalPage; '7iz5wC#
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/** the number of current page */ BoD{fg
privateint currentPage; 2HX/@ERhmu
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/** the begin index of the records by the current 6Yu:v
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query */ p~D}Iyww1_
privateint beginIndex; djd/QAfSC
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/** The default constructor */ -ng1RA>
public Page(){ mRk)5{
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} Gm~([Ln{
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/** construct the page by everyPage BWt`l,nF
* @param everyPage Y;i=c6
* */ o) )` "^
public Page(int everyPage){ c6h?b[]
this.everyPage = everyPage; {bj!]j
} #<{v~sVp&
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/** The whole constructor */ X/5m}-6d]
public Page(boolean hasPrePage, boolean hasNextPage, X\^nV
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int everyPage, int totalPage, X9x`i
int currentPage, int beginIndex){ W06aj ~7Z
this.hasPrePage = hasPrePage; ?cU,%<r
this.hasNextPage = hasNextPage; |]\zlH"w
this.everyPage = everyPage; fY<#KM6X
this.totalPage = totalPage; AwM`[`ReE
this.currentPage = currentPage; `7"="T~ *
this.beginIndex = beginIndex; 5pQpzn=
} `fv5U%
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/** 9"~ FKMN
* @return Q,U0xGGz
* Returns the beginIndex. DAn2Pqf
*/ \"lz,bT
publicint getBeginIndex(){ I G1];vX
return beginIndex; V_7\VKR
} P9v(5Z00|d
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/** ;ALWL~Xm
* @param beginIndex #QNN;&L]R
* The beginIndex to set. AA\a#\#Z3
*/ dN8Mfa)
publicvoid setBeginIndex(int beginIndex){ Q}BMvR 9w
this.beginIndex = beginIndex; z^bS+0S5x!
} VAPeMO
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/** ">V1II
7
* @return >|f"EK}m!
* Returns the currentPage. l\<.*6r
*/ fO<40!%9cQ
publicint getCurrentPage(){ sd%j&Su#4
return currentPage; +nYFLe
} d$!Q6ux;
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/** ~\":o:qyc
* @param currentPage {>>X3I
* The currentPage to set. X[B P0:`t
*/ kR =sr/{
publicvoid setCurrentPage(int currentPage){ :So<N}&
this.currentPage = currentPage; -FZC|[is
} fi?4!h
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/** GJ9>i)+h;
* @return yD+4YD
* Returns the everyPage. Exb64n-_=
*/ R%UTYRLUn
publicint getEveryPage(){ 0jTReY-W
return everyPage; z8\YMr6o
} K[[~G1Z
ee {ToK
/** +B*]RL[th
* @param everyPage kwjO5OC8
* The everyPage to set. [.#nM
*/ [ZWAXl
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publicvoid setEveryPage(int everyPage){ 'D\X$^J^
this.everyPage = everyPage; ]$smFF
} 'ZbWr*bo
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/** *.W3V;K
* @return -.Wcz|
* Returns the hasNextPage. gAAC>{Wh
*/ -S$F\%
publicboolean getHasNextPage(){ Xa`Q;J"h
return hasNextPage; 5kGniG?T#
} tZ_'>7)
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/** Fp\;j\pfw
* @param hasNextPage )qy?x7
* The hasNextPage to set. bP18w0>,
*/ ~I||"$R
publicvoid setHasNextPage(boolean hasNextPage){ @KQ>DBWQM
this.hasNextPage = hasNextPage; EI_-5Tt RD
} 1 Pk+zBJ$
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/** \.L jA_
* @return "J(M. Y
* Returns the hasPrePage. J!:BCjRdw
*/ ?eS;Yc
publicboolean getHasPrePage(){ :>FN|fz
return hasPrePage; J(]|)?x2
} kL8rqv^
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/** w;'XqpP$*|
* @param hasPrePage ~?\U];l
* The hasPrePage to set. 9$)&b\D
*/ JL M Xkcc
publicvoid setHasPrePage(boolean hasPrePage){ =gVMt
this.hasPrePage = hasPrePage; jQ{ @ol}n
} H^d?(Svh
l7-lXl"%q
/** q`xc h[H
* @return Returns the totalPage. v>8.TE~2
* #W~jQ5NS\
*/ sOhn@*X
publicint getTotalPage(){ Qs1CK;+zU
return totalPage; p:08q
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} <K CI@
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/** QAkK5,`vV.
* @param totalPage |=0vgwd"S
* The totalPage to set. 9pLe8D
*/ x Lan1V
publicvoid setTotalPage(int totalPage){ ]0UYxv%]
this.totalPage = totalPage; IxbQ6
} o GuAF q
$;^|]/-
} WARiw[
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 z~t0l
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个PageUtil,负责对Page对象进行构造: \5a.JfF
java代码: UFj H8jSBx
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e]~p:
/*Created on 2005-4-14*/ }m+Q(2
package org.flyware.util.page; #D9.A7fCc5
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import org.apache.commons.logging.Log; i^DMnvV.
import org.apache.commons.logging.LogFactory; [FBS|v#T
k[f2`o=
/** f&<+45JI
* @author Joa R+HX'W
* ]'5Xjcx
*/ KElEGW
publicclass PageUtil { L-9fo-
\ ca<L
privatestaticfinal Log logger = LogFactory.getLog )0/9
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(PageUtil.class); r^m&<)Ca
r D@*xMW
/** a3 }V/MY
* Use the origin page to create a new page gvI!Ice#
* @param page l`"?KD
* @param totalRecords "qgwuWbM
* @return jL-2
}XrA
*/ |R.yuSL)(
publicstatic Page createPage(Page page, int -riX=K>$
f#z:ILG=
totalRecords){ ~dS15E4-Pp
return createPage(page.getEveryPage(), e@P(+.Ke
~cc }yDe
page.getCurrentPage(), totalRecords); lTC0kh
} ao)';[%9s
35l%iaj]G5
/** /ZyMD(_J
* the basic page utils not including exception
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DQGrXMpV0
handler FO*Gc
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* @param everyPage u\ _yjv#
* @param currentPage e|oMbTZ5m
* @param totalRecords {D[6=\F
* @return page k9%o{Uzy
*/ t`B@01;8A
publicstatic Page createPage(int everyPage, int T +vo)9w
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currentPage, int totalRecords){ :\[l~S
everyPage = getEveryPage(everyPage); (RFH.iX
currentPage = getCurrentPage(currentPage); %*Ex2we&
int beginIndex = getBeginIndex(everyPage, pg%(6dqK4
N>(w+h+
currentPage); glLVT
i
int totalPage = getTotalPage(everyPage, W{-g?)Tou
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totalRecords); )
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boolean hasNextPage = hasNextPage(currentPage, b-
- tl@H
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totalPage); opH!sa@U
boolean hasPrePage = hasPrePage(currentPage); *;@wPT
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returnnew Page(hasPrePage, hasNextPage, 1r=cCM
everyPage, totalPage, A,F~*LXm
currentPage, qFWN._R
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beginIndex); ,NQ!d4~D
} >
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privatestaticint getEveryPage(int everyPage){ 2PAu>}W*
return everyPage == 0 ? 10 : everyPage; `,'/Sdr
} SOI=~BGd)
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privatestaticint getCurrentPage(int currentPage){ bkd`7(r
return currentPage == 0 ? 1 : currentPage; u@dvFzc
} <<!fA><W
'S3<' X
privatestaticint getBeginIndex(int everyPage, int 0g[ %)C
YVccO~!8
currentPage){ /K|(O^nw
return(currentPage - 1) * everyPage; TR3U<:
} a
U\|ZCH\]
R ` ViRJh
privatestaticint getTotalPage(int everyPage, int PcC@}3
R ABw(b
totalRecords){ Tc(=J7*r&
int totalPage = 0; Dizz ?O
%[|^7
if(totalRecords % everyPage == 0) &:l-;7d
totalPage = totalRecords / everyPage; `rVru= zoy
else d/R!x{$-f
totalPage = totalRecords / everyPage + 1 ; I(^0/]'
d1/WUKmbZ
return totalPage; }. &ellNQ
}
U${W3Ra
hnFpC1TO
privatestaticboolean hasPrePage(int currentPage){ {A/^;X{N^
return currentPage == 1 ? false : true; 8;?4rrS
} e ymv/
~1+6gG
privatestaticboolean hasNextPage(int currentPage, zx%WV@O9
V<UChD)N`
int totalPage){ J'Pyn
return currentPage == totalPage || totalPage == vS\ 2zwb}
yD~,+}0)
0 ? false : true; $6Q^ur:
} V~/G,3:0y%
VaD+:b4
_CHzwNU
} I4"p]>Y"
qS\#MMsTd
kL1<H%1'
[eD0L71[
[XY%<P3D
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 J-
S.m(
;(?tlFc
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 T^7Cv{[
s21}
a,eB
做法如下: 67iI wY*8'
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 !Q[v"6?
y2I7Zd .
的信息,和一个结果集List: 5csh8i'V
java代码: O?X[&t
+7b8 ye
_nqnO8^IG4
/*Created on 2005-6-13*/ Mq$K[]F
package com.adt.bo; ULAr!
jn5xYKv
import java.util.List; 0FOB5eBR
! $$>D"
import org.flyware.util.page.Page; Nhs!_-_I
dLp1l2h!0
/** tfU*U>j
* @author Joa o=YOn&@%
*/ hiS|&5#
publicclass Result { E@ :9|5
U=bx30brh%
private Page page; L"&T3i
Z8v 8@Y
private List content; ^0.8-RT
7Jlkn=9e:
/** 3Cj)upc
* The default constructor I&+.I K_
*/ w&?XsO@0W
public Result(){ p{L;)WTI
super(); +b-ON@9]J`
} cp@Fj"
2Xl+}M.:Y
/** j+h+Y|4J
* The constructor using fields hty'L61\z
* B4b'0p
* @param page |H
t5a.
* @param content z&gmaYwq
*/ (S!UnBb&
public Result(Page page, List content){ kxhsDD$@p
this.page = page; 59oTU
this.content = content; B2[f1IMI
} }i!+d,|f
.rK0C)
/** OV]xo8a;
* @return Returns the content. t.ulG
*
*/ M>i(p%
publicList getContent(){ tQ9%rb
return content; aLh(8 ;$
} sYS
8]JU
#p(c{L!
/** t,9+G<)>H
* @return Returns the page. 2V@5:tf
*/ Y_Gd_+oJ
public Page getPage(){ =v<w29P(g
return page; YcA. Bn|as
} %k#+nad
b23A&1X
/** */e$S[5
* @param content "0!h-bQN
* The content to set. yF)J7a:U
*/ zjUQ]
public void setContent(List content){ 9Rk(q4.OP
this.content = content; >.qFhO\1so
} iLnW5yy
i?/Q7D<P
/** ^^v3iCT
* @param page zls^JTE
* The page to set. zdwQpB,+^
*/ @m5J%8>k
publicvoid setPage(Page page){ WVeNO,?ytS
this.page = page; !kSemDC
} iTinZ!Ut
} fJ/INL
j9k:!|(2'
9Vm
aB
&MpLm&
gg`{kN^r.a
2. 编写业务逻辑接口,并实现它(UserManager, pl>b 6 |
OH>.N"IG
UserManagerImpl) 9^!.!%6O$
java代码: 9YI@c_1 Q
;((t|
wK2$hsque
/*Created on 2005-7-15*/ QT+kCN
package com.adt.service; US)i"l7:H*
us.[wp'Sh
import net.sf.hibernate.HibernateException; %O9 Wm_%
~S('\h)1
import org.flyware.util.page.Page; ^Z)7Z%
O
W$jRS
import com.adt.bo.Result; )"\=
_E#
~a_hOKU5
/** 1T#-1n%[k(
* @author Joa DPf].i#
*/ cgG*7E
publicinterface UserManager { .h
<=C&Yg
fcdXj_u
public Result listUser(Page page)throws G
T~rr*X
}`L;.9
HibernateException; |y7TYjg6
M<Bo<,!ua
} n*9QSyJN]
+}m`$B}mJ
<9&GOaJ
h1q3}-
#v(As)4^
java代码: -F/)-s6#!'
FZgf"XM>
Zw)=Y.y!
/*Created on 2005-7-15*/ )vq}$W!:9
package com.adt.service.impl; $@6q5Iz!&
( 72%au
import java.util.List; Ly(iq
dXDyY
import net.sf.hibernate.HibernateException; }uMu8)Q
\'=svJ
import org.flyware.util.page.Page; P6%qNR/ x
import org.flyware.util.page.PageUtil; $|7"9W}m*
C)m@/w
import com.adt.bo.Result; r4u,I<ZbH
import com.adt.dao.UserDAO; ]A[}:E 5}
import com.adt.exception.ObjectNotFoundException; b6S"&hs
import com.adt.service.UserManager; ozsd6&z5l
r } Wdj
/** cl`kd)"v
* @author Joa NdJ]\>5oN,
*/ \
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publicclass UserManagerImpl implements UserManager { \#biwX
8cfsl lI
private UserDAO userDAO; yE
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I 8i|tQz
/** V #vkj
* @param userDAO The userDAO to set. /QS Nv
*/ 5q4wREh
publicvoid setUserDAO(UserDAO userDAO){ yUcU-pQ
this.userDAO = userDAO; 4%}iKoT
} G-D}J2r=F
Ox
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/* (non-Javadoc) .&5 3sJ0{
* @see com.adt.service.UserManager#listUser R1hmJ
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uu5 p
(org.flyware.util.page.Page) DBy%"/c
*/ ,MHK|8!
public Result listUser(Page page)throws 1WaQWZ:=
-ik$<>{X
HibernateException, ObjectNotFoundException { @[FO;4w
int totalRecords = userDAO.getUserCount(); s-6$C
if(totalRecords == 0) L7lpOy4k
throw new ObjectNotFoundException M`7lYw\Or!
@ebY_*
("userNotExist"); N\s-{7K
page = PageUtil.createPage(page, totalRecords); y+^KVEw
List users = userDAO.getUserByPage(page); %a8e_
returnnew Result(page, users); SIM>Lz
} V,zFHXO
~9YEb
} ?pQ0*
O0
'ym Mu}q
DQ$m@_/4w
l^tRy_T:-
Z[!kEW
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 bOYM-\
{y
dM}c-=w`
询,接下来编写UserDAO的代码: v\(6uej^
3. UserDAO 和 UserDAOImpl: +bso4 }rS
java代码: q+qF;7dN@
[fwk[qFa
K
d#(eGe
/*Created on 2005-7-15*/ ~"bBwPI
package com.adt.dao; ?Z!R
|pknaz
import java.util.List; bWp)'mx5u
(3K,f4S@
import org.flyware.util.page.Page; /^K-tz-R
\0i0#Dt9
import net.sf.hibernate.HibernateException; <2O#!bX1
y'6l fThT
/** |d\1xTBLp
* @author Joa ME>Sh~C\
*/ n[;)(
publicinterface UserDAO extends BaseDAO { C!K&d,M
Y ajAz5N
publicList getUserByName(String name)throws ( ?e
Et&
jU 3ceXV
HibernateException; ijcF[bmE
K{Nj-Rqd
publicint getUserCount()throws HibernateException; @G>eCj
B)d 4]]4\\
publicList getUserByPage(Page page)throws "Qc4v@~)
4K~>
HibernateException; am'K$s
W3('1
} ]T40VGJ:h
u!HbS*jqq
Ke[`zui@?
h0x'QiCc
Jz0AYiCq
java代码: _/ 5
vEE\{1
Vv`94aQTD
/*Created on 2005-7-15*/ S]}}r)
package com.adt.dao.impl; O#!|2qN
[Tvdchl OC
import java.util.List; lkp$rJ#6
Rw63{b/
import org.flyware.util.page.Page; J`; 9Z
K4RQ{fWpm
import net.sf.hibernate.HibernateException; 00>knCe6
import net.sf.hibernate.Query; aU.!+e%_
EpT^r8I
import com.adt.dao.UserDAO; 8B "^}y\0
&\ad.O/Q
/** U.Z5;E0:
* @author Joa 0Bkc93
*/ 5)rN#_BKj
public class UserDAOImpl extends BaseDAOHibernateImpl :Ez*<;pF'
;S&anC#E
implements UserDAO { cl{mRt0
I!lR 7%
/* (non-Javadoc) M`9|8f,!a
* @see com.adt.dao.UserDAO#getUserByName ".pQM.T
1(i%nX<U
(java.lang.String) _K!)0p
*/ 1'\s7P
publicList getUserByName(String name)throws -) +B!"1
}t|i1{%_
HibernateException { BNO+-ob-
String querySentence = "FROM user in class X-CoC
|NTqJ j
com.adt.po.User WHERE user.name=:name"; 8"[{[<-
Query query = getSession().createQuery y\9#"=+
m}beT~FT_
(querySentence); ^mut-@ N9
query.setParameter("name", name); !F Zg'
9
return query.list(); C0^r]^$Z
} $EdL^Q2KAy
fU.z_T[@
/* (non-Javadoc) (_N(K`4#W
* @see com.adt.dao.UserDAO#getUserCount() U9\w)D|+eE
*/ DdeKZ)8
publicint getUserCount()throws HibernateException { ]Ee$ulJ02
int count = 0; eT2Tg5Etc
String querySentence = "SELECT count(*) FROM #op0|:/N
?5%o-hB|
user in class com.adt.po.User"; n-GoG(s..b
Query query = getSession().createQuery cQ`0d3
s?Gv/&
(querySentence); T;,,!
count = ((Integer)query.iterate().next c:B` <
I,Jb_)H&t
()).intValue(); r0pwKRE~t
return count; 0hXx31JN N
} >I;.q|T
p%#'`*<a_
/* (non-Javadoc) w xaMdA
* @see com.adt.dao.UserDAO#getUserByPage 4~;M\h
d\c)cgh%
(org.flyware.util.page.Page) q}z`Z/`/
*/ rzvKvGd#N
publicList getUserByPage(Page page)throws IF6-VFY:6
:+?rnb)N
HibernateException { 93,7yZ5#
String querySentence = "FROM user in class q(2ZJn13f
?O]RQXsZ2
com.adt.po.User"; X]W(
Query query = getSession().createQuery uA t{WDHm
_ib
@<%
(querySentence); AW!A+?F6
query.setFirstResult(page.getBeginIndex()) iG=Di)O
.setMaxResults(page.getEveryPage()); }{&;\^i
return query.list(); CHCT
e
} [;~"ctf{
<33,0."K
} mO8/eVws[M
/*M3Ns1@2
aej'c bO
wL>;_KdU`
<qI!Dj{
至此,一个完整的分页程序完成。前台的只需要调用 b9v<Jk
x2OAkkH\]i
userManager.listUser(page)即可得到一个Page对象和结果集对象 /?S^#q>m%
xm=$D6O:
的综合体,而传入的参数page对象则可以由前台传入,如果用 & Yx12B\
}iUpBn
webwork,甚至可以直接在配置文件中指定。 fILvEf4b
~Jj~W+h
下面给出一个webwork调用示例: Tgbq4xR(
java代码: -]n%+,3L
y(^\]-fE
.t&G^i'n
/*Created on 2005-6-17*/ cVr+Wp7K#|
package com.adt.action.user; G9GLRdP
ekmWYQ
~
import java.util.List; BP\6N%HC%&
@Q;s[Kg{!
import org.apache.commons.logging.Log; mwI7[I2q
import org.apache.commons.logging.LogFactory; uaky2SgN
import org.flyware.util.page.Page; kZi/2UA5Z
dB:c2
import com.adt.bo.Result; iHvWJ<"jR
import com.adt.service.UserService; MhB>bnWXR
import com.opensymphony.xwork.Action; #k)t.P
Q
k;qWiYMV
/** 3 4&xh1=3
* @author Joa ~sq@^<M)s
*/ ?a1pO#{Dg
publicclass ListUser implementsAction{ 6)20%*[
+m/n~-6q
privatestaticfinal Log logger = LogFactory.getLog M9Nr/jE
:l?mNm5
(ListUser.class); 2. {/ls
TgHUH>k
private UserService userService; ]M'~uTf
k*Aee7
private Page page; $2-_j)+
=+q\Jh
privateList users; j5]ul!ji
Y4_xV&
/* l/\D0\x2
* (non-Javadoc) AD@ {7
* Z aS29}
* @see com.opensymphony.xwork.Action#execute() (Fq:G) $
*/ 9b@yDq3hQ
publicString execute()throwsException{ tE-g]y3
Result result = userService.listUser(page); M* {5> !\
page = result.getPage(); Z/|=@gpw
users = result.getContent(); :3b02}b7
return SUCCESS; Q(e
} 8.+
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{esb"beGLa
/** xH}bX- m
* @return Returns the page. 25@@-2h @
*/ -~X[j2
public Page getPage(){ 6E9/z
return page; XP?)xDr8
} vJV/3-yX
&
d$X:
/** S2nX{=
* @return Returns the users. 0'YJczDq:7
*/ mm.%Dcn
publicList getUsers(){ 7?y7fwER
return users; ~-B+7
} 1MT,A_L
f*9O39&|
/** 7q5*grm
* @param page =2ED
w_5E
* The page to set. g2=PZR$
*/ y~VI,82*
publicvoid setPage(Page page){ $em'H,*b3
this.page = page; )S/=5Uc
} z0 #2?o
,CuWQ'H
/** qPN9Put
* @param users )feZ&G]
* The users to set. n=AcN
*/ Kpa$1x
publicvoid setUsers(List users){ D!.1R!(Z
this.users = users; w*;"@2y;eY
} `u PLyS.
lBAu@M
/** m]vV.pwv
* @param userService fFWi
3.
* The userService to set.
*
1xs/$`
*/ #.$y
publicvoid setUserService(UserService userService){ R^P>yk8
this.userService = userService; "Aw)0a[j1
} H\\FAOj
} @qj]`}Gx'
|r36iUHZS
Id>4fF:o
t8rFn
m8e()8lZ3
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, Kfr1k
kxJ[Bi#
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 j0V/\Ep)T<
Pd(_
么只需要: )5gj0#|CG@
java代码: 7')W+`o8eL
,]W|"NUI
<JU3sXl
<?xml version="1.0"?> =WBfaxL}
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork TsG x2[
/kg#i&bP~
1.0//EN" "http://www.opensymphony.com/xwork/xwork- rD a{Ve
&
d2`{H
1.0.dtd"> js@L%1r#L
6Io}3}3
<xwork> zB~< @
Y:t?W
<package name="user" extends="webwork- :zLf~W
T<?kH
interceptors"> FO:L+&hr?>
^\?Rh(pu
<!-- The default interceptor stack name .g\Oj0Cbxh
K,,) FM
--> w}zmcO:x
<default-interceptor-ref k0K$OX*:e
p'1/J:EnV
name="myDefaultWebStack"/> M*kE |q/K
0doJF@H
<action name="listUser" IDFzyg_
EG\;l9T
class="com.adt.action.user.ListUser"> /lu|FWbEw
<param %Uz\P|6PO
b/]4#?g
name="page.everyPage">10</param> jy?*` q1]
<result 'wG1un;t
wlaPE8Gc
name="success">/user/user_list.jsp</result> 31a lQ\TH
</action> r]Wt! oHm5
n$r`s`}
</package> #S'uqP!
#~"IlBk\
</xwork> ,_Bn{T=U
NR1M W^R
]rH[+t-
J&,hC%]
%oTBh* K'o
x5BS|3W$a
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 X3kFJ{
Opc szq5n
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。 TnK<Wba
%HoD)OJe
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 &{a!)I>
$5)#L$!,]
NimgU Fa
(EY@{'.&
3?]81v/
我写的一个用于分页的类,用了泛型了,hoho h%ys::\zF
Y6VJr+Ap(
java代码: A#T"4'#?<
PENB5+1OK
!V3+(o1
package com.intokr.util; :VZS7$5
d$3md<lIB
import java.util.List; >{tn2Fkg>
6{=U=
*
/** wTU$jd1;+
* 用于分页的类<br> w|s2f`!
* 可以用于传递查询的结果也可以用于传送查询的参数<br> n-cI~Ax+4
* `hkvxt
* @version 0.01 YYYF a
* @author cheng $jE<n/8
*/ EOXkMr
public class Paginator<E> {
<KU0K
privateint count = 0; // 总记录数 hQm=9gS
privateint p = 1; // 页编号 0't)-Pj+,
privateint num = 20; // 每页的记录数 =CK% Zo
privateList<E> results = null; // 结果 Jcze.t
M?"4{
/** ofQs
/
* 结果总数 O0L]xr
*/ s)r!3HS
publicint getCount(){ "I/05k K
return count; K {v^Y,B
} _Fa\y ZX
/-[vC$B"
publicvoid setCount(int count){ iIX%%r+
this.count = count; A'z]?xQR
} Ia}qDGqPp!
>B**fZ~L
/** ZY`9
* 本结果所在的页码,从1开始 Uq#2~0n>
* 1Ys=KA-!_x
* @return Returns the pageNo. yV:8>9wE8
*/ (l{8Ixs
publicint getP(){ ;P)oKx
return p; JP<j4/
} 1n^N`lD8]6
20|_wAA5
/** ~
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* if(p<=0) p=1 cLf90|YFp
* L{%L*z9J
* @param p FXJ0
G>F
*/ %u66H2
publicvoid setP(int p){ uD=Kar
if(p <= 0) Eb[;nk?
p = 1; t;w<n"
this.p = p; <PDCM8
} !?JZ^/u
|> STb\
/** 94#,dA,M
* 每页记录数量 qP#LJPaS
*/ ~Yk^(hl2
publicint getNum(){ x;u#ec4
return num; r4SwvxhG
} N)g _LL>^
L.'61ZU
/** w gS'/
* if(num<1) num=1 zFm`e:td
*/ V_J0I*Qa4
publicvoid setNum(int num){ &!X<F,
if(num < 1) HAK,z0/
num = 1; ^t4^gcoZ4Z
this.num = num; ';FJs&=I
} wz`% (\
@`L;_S+
/** V*\hGNV
* 获得总页数 S}JOS}\^j
*/ l}L81t7f
publicint getPageNum(){ Pq [_(Nt
return(count - 1) / num + 1; DfAF-Yhut
} i6_}
Ct)58f2
/** zni9
* 获得本页的开始编号,为 (p-1)*num+1 pV ^+X}
*/ ZMgsuzg
publicint getStart(){ hO8xH +;
return(p - 1) * num + 1; 1<_][u@
} 1(BLdP3&
g]vB\5uA:
/** K{DC{yLu
* @return Returns the results. 5HOl~E
*/ J"AR3b@,$?
publicList<E> getResults(){ ~@c<5 -`{
return results; (7G4 v
} s oY\6mHio
'/8/M{`s
public void setResults(List<E> results){ "ZGP,=?y2
this.results = results; ,EEAxmf
} +S4>}2N33
tI{]&dev
public String toString(){ Uyb0iQ-,s
StringBuilder buff = new StringBuilder iZn0B5]ikj
x>EL|Q=?
(); yk4@@kHW
buff.append("{"); c46-8z$
buff.append("count:").append(count); B3ItZojAuw
buff.append(",p:").append(p); V>QyiB
buff.append(",nump:").append(num); 9{;L7`<
buff.append(",results:").append #8et91qw
`r1}:`.m,
(results); 3!p`5hJd
buff.append("}"); s;TB(M~i[
return buff.toString(); (%L/|F_
} Hdew5Xn(:
4aOz=/x2
} !2!Zhw2u
5]dlD #
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