Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 2XR!2_)O5
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 TzKM~a#
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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 U^_\V BAk
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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 WOO3z5 La
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分页支持类: =X'[r
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java代码: ;Rv WF )
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package com.javaeye.common.util; `+Nv=vk
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import java.util.List; ndFVP;q
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publicclass PaginationSupport { 6$OmOCA%
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publicfinalstaticint PAGESIZE = 30; -7!L]BcZ.
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privateint pageSize = PAGESIZE; r1HG$^
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privateList items; 4rDVCXE
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privateint totalCount; ]\rQ{No
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privateint[] indexes = newint[0];
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privateint startIndex = 0; \dQc!)&C9
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public PaginationSupport(List items, int B*:I-5
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totalCount){ zsuqRM
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setPageSize(PAGESIZE); jwjLxt
setTotalCount(totalCount); C[fefV9g2
setItems(items); vVMoCG"f
setStartIndex(0); qMEd
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} *ELU">!}G
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public PaginationSupport(List items, int B.=n U
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totalCount, int startIndex){ gdCit-3
setPageSize(PAGESIZE); .RmFYV0,
setTotalCount(totalCount); Y*#xo7#B
setItems(items); [4xZy5V
setStartIndex(startIndex); n><ad*|MX
} 8Vz!zYl
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public PaginationSupport(List items, int bLS10^g5
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totalCount, int pageSize, int startIndex){ auGK2i
setPageSize(pageSize); &bq1n_
setTotalCount(totalCount); 4Y'Ne2M{
setItems(items); j|8!gW
setStartIndex(startIndex); _N:$|O#
} p5qfv>E8)
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publicList getItems(){ &*o4~6pQ#
return items; !\|
} 6Br^Ugy
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publicvoid setItems(List items){ W\-`}{B_/
this.items = items; u`wD6&y*
} O`Qke
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publicint getPageSize(){ 5s\;7>
return pageSize; \^0>h`[
} "c} en[
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publicvoid setPageSize(int pageSize){ 4pMp@b
this.pageSize = pageSize; '4 d4i
} $aEv*{$y
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publicint getTotalCount(){ Jw=7eay$F
return totalCount; L8n?F#q
} Qu Mv1)n
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publicvoid setTotalCount(int totalCount){ I@z@s}x>
if(totalCount > 0){ dh%O {t
this.totalCount = totalCount; "6IZf>N@#
int count = totalCount / Z&?4<-@6\p
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pageSize; g$2#TWW5
if(totalCount % pageSize > 0) 2%fzRXhu%
count++; $bp$[fX(e
indexes = newint[count]; W4av?H
for(int i = 0; i < count; i++){ 1!V[fPJ
indexes = pageSize * WJ-.?
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} IO&U=-pn&
}else{ 9W(&g)`
this.totalCount = 0; ]v5/K
} pam9wfP
} &n8Ja@Y]
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publicint[] getIndexes(){ vO$cF*
return indexes; 8a@k6OZ
} Z5oDj|&l}
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publicvoid setIndexes(int[] indexes){ b{-"GqMO
this.indexes = indexes; 6wu`;>
} Q|+ a
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publicint getStartIndex(){ $Bncdf
return startIndex; LHx ")H?,
} -z.
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publicvoid setStartIndex(int startIndex){ 5Hj/7~ =
if(totalCount <= 0) k kD#Bb
this.startIndex = 0; |6?s?tC"u
elseif(startIndex >= totalCount) P}a$#a'!
this.startIndex = indexes t {1 [Ip
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[indexes.length - 1]; "8ZV%%elp
elseif(startIndex < 0) >oyf i:
this.startIndex = 0; t@#5
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else{ s}Go")p<:
this.startIndex = indexes vvY?8/
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[startIndex / pageSize]; 0e#PN@
} z]%@r 7
} ;c]O *\/
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publicint getNextIndex(){ 8Vn
int nextIndex = getStartIndex() + e~)4v
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pageSize; wTR?8$
if(nextIndex >= totalCount) PCgr`($U
return getStartIndex(); 52#
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else ziO(`"v
return nextIndex; %nq<nfDT
} ,Js_d
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publicint getPreviousIndex(){ y_W?7S
int previousIndex = getStartIndex() - X#0yOSR
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pageSize; 3l`"(5
if(previousIndex < 0) M Tl
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return0; =bJ$>Djp
else ,Iz9!i
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return previousIndex; *wmkcifF;
} S{2;PaK
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} ":/Vp,g
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抽象业务类 -b+)Dp~$p
java代码: r^"sZk#
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/** _O87[F1
* Created on 2005-7-12 b9i_\
*/ W2$rC5|
package com.javaeye.common.business; xZ2 1iQeN
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import java.io.Serializable; +N,Fq/x
import java.util.List; :&z!o"K
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import org.hibernate.Criteria; V?^qW#AG
import org.hibernate.HibernateException; og+Vrd
import org.hibernate.Session; ?Y\WSI?i
import org.hibernate.criterion.DetachedCriteria; {*CG&-k2D
import org.hibernate.criterion.Projections; :u=y7[I
import U$a)lcJd
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org.springframework.orm.hibernate3.HibernateCallback; gV ':Xe
import 5B8/"G
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org.springframework.orm.hibernate3.support.HibernateDaoS ~/SLGyu
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upport; 4Vf-D%
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import com.javaeye.common.util.PaginationSupport; :nnch?J_
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public abstract class AbstractManager extends O@HD'
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HibernateDaoSupport { R"t2=3K
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privateboolean cacheQueries = false; r_'];
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privateString queryCacheRegion; T DPQ+Kg_
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publicvoid setCacheQueries(boolean 8BS Nm
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cacheQueries){ +\PLUOk
this.cacheQueries = cacheQueries; <Z~Nz>'r
} yQu/({D
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publicvoid setQueryCacheRegion(String ph2
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queryCacheRegion){ 5PpS/I:on
this.queryCacheRegion = Y3)*MqZlF
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queryCacheRegion; +]H!q
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} !,7)ZW?*8
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publicvoid save(finalObject entity){ %3HF_DNOY=
getHibernateTemplate().save(entity); efbJ2C
} 3ox|Mz<aZX
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publicvoid persist(finalObject entity){ +H?
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getHibernateTemplate().save(entity); K7q R
} h2+"e# _
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publicvoid update(finalObject entity){ U?:?NC=1{
getHibernateTemplate().update(entity); O6q5qA
} f.v JJa
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publicvoid delete(finalObject entity){ YcSPU(
getHibernateTemplate().delete(entity); =G 'c %
} 56Lt "Z F
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publicObject load(finalClass entity, [A;0IjKam
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finalSerializable id){ `,c~M
return getHibernateTemplate().load [RDY(}P%
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(entity, id); Ob|tA
} 4 `}6W>*R
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publicObject get(finalClass entity, =AuxMEg
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finalSerializable id){ "@xL9[d
return getHibernateTemplate().get 2.a{,d
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(entity, id); BL\H@D
} $cO-+Mr-~
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publicList findAll(finalClass entity){ P[ ,
return getHibernateTemplate().find("from 8(-N;<Ef2
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" + entity.getName()); cw~-%%/
} gp^xl>E
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publicList findByNamedQuery(finalString .7Itbp6=R
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namedQuery){ )},/=#C0
return getHibernateTemplate o~'UWU'#
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().findByNamedQuery(namedQuery); PW*[(VX
} pG$l
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publicList findByNamedQuery(finalString query, @WzrrCpj
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finalObject parameter){ }pT>dbZ
return getHibernateTemplate QLH6Nmk
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().findByNamedQuery(query, parameter); >% E=l
} 5e
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publicList findByNamedQuery(finalString query, o{MmW~/o&
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finalObject[] parameters){ |
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return getHibernateTemplate l`E KL2n
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().findByNamedQuery(query, parameters); tfd!;` B
} k=.pcDX
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publicList find(finalString query){ Y:5Gp8Vi
return getHibernateTemplate().find NKu*kL}W=
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(query); 5G WC
} I oC}0C7
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publicList find(finalString query, finalObject 2NWQiSz
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parameter){ W&9X <c*
return getHibernateTemplate().find NS^+n4
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(query, parameter); S>EO6z#
} RjG=RfB'V
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public PaginationSupport findPageByCriteria LhtA]z,m
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(final DetachedCriteria detachedCriteria){ T |h'"3'
return findPageByCriteria |F?/L>
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); oJor
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} hXP'NS`iv
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public PaginationSupport findPageByCriteria uBxs`'C
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(final DetachedCriteria detachedCriteria, finalint [!>DQE
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startIndex){ #~;:i
return findPageByCriteria FK`M+ j
:pg]0X;
(detachedCriteria, PaginationSupport.PAGESIZE, C_V5.6T!
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startIndex); \={A%pA;@{
} +>o}
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public PaginationSupport findPageByCriteria Mp`i@pm+
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(final DetachedCriteria detachedCriteria, finalint D=!5l4
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pageSize, R\n*O@E
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finalint startIndex){ C;oT0(
return(PaginationSupport) E|omC_h
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getHibernateTemplate().execute(new HibernateCallback(){ CC{{@
publicObject doInHibernate {x/)S*:Z
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(Session session)throws HibernateException { E0<$zP}V}F
Criteria criteria = ^WmP,Xf#
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detachedCriteria.getExecutableCriteria(session); >r5s>A[YC
int totalCount = QAKA3{-(
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((Integer) criteria.setProjection(Projections.rowCount W)m\q}]FYz
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()).uniqueResult()).intValue(); vHxLn/
criteria.setProjection cXG$zwS\
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(null); s!F`
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List items = u(Y?2R
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criteria.setFirstResult(startIndex).setMaxResults ca!DZ%y
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(pageSize).list(); o<nkK+=Afm
PaginationSupport ps = t{RdqAF
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new PaginationSupport(items, totalCount, pageSize, (b>B6W\&
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startIndex); 23~KzC
return ps; %SlF7$
} R`!'c(V
}, true); "`8~qZ7k
} !Au 9C
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public List findAllByCriteria(final m*Q*{M_e
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DetachedCriteria detachedCriteria){ $ @Fvl-lK
return(List) getHibernateTemplate W2G@-`,
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().execute(new HibernateCallback(){ ;E]^7T
publicObject doInHibernate 25CO_
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(Session session)throws HibernateException { RbGq$vYol/
Criteria criteria = 5zR9N>!c
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detachedCriteria.getExecutableCriteria(session); hAv.rjhw_
return criteria.list();
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} /agX! E4s
}, true); 6e.?L
} {X'D07 q
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public int getCountByCriteria(final =&
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DetachedCriteria detachedCriteria){ 3iC$ "9!p
Integer count = (Integer) /,m!SRJ
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getHibernateTemplate().execute(new HibernateCallback(){ ap[{`u
publicObject doInHibernate [[sfuJD
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(Session session)throws HibernateException { NHjZ`=Js
Criteria criteria = tjIT4
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detachedCriteria.getExecutableCriteria(session); mcB8xE
return
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criteria.setProjection(Projections.rowCount mqFo`Ee
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()).uniqueResult(); UZ` <D/
} #ovmX
}, true); xOAA1#
return count.intValue(); 4$^\s5 K
} 8vL2<VT;
} h
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用户在web层构造查询条件detachedCriteria,和可选的 4Ucs9w3[
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 Hrk]6*
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PaginationSupport的实例ps。 <0w"$.K#3
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ps.getItems()得到已分页好的结果集 :< d.
ps.getIndexes()得到分页索引的数组 q9h3/uTv
ps.getTotalCount()得到总结果数 J2BCaAwEP,
ps.getStartIndex()当前分页索引 T@ 4R|P&{)
ps.getNextIndex()下一页索引 O)jpnNz
ps.getPreviousIndex()上一页索引 5{"v/nXV
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ^ 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 _ g8CvH)?!
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一下代码重构了。 vmj'X>Q
7K 'uNPC
我把原本我的做法也提供出来供大家讨论吧: mp:xR ^5c
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首先,为了实现分页查询,我封装了一个Page类: 4F`&W*x
java代码: 0Xw$l3@N^
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/*Created on 2005-4-14*/ 7@1GSO: Yf
package org.flyware.util.page; A/c #2
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/** {44#<A<
* @author Joa _m.w5nJ
* Iysp)
*/ QMhvyzkS
publicclass Page { U!\~LKfA
kj>!&W57
/** imply if the page has previous page */ rQD^O4j R
privateboolean hasPrePage; dJjkH6%}
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/** imply if the page has next page */ @Cml^v@`L
privateboolean hasNextPage; `oU|U!|
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/** the number of every page */ kK|D&Xy`
privateint everyPage; h5Ee*De
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/** the total page number */ g.*DlD%%
privateint totalPage; !+u
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/** the number of current page */ QnA~,z/.w
privateint currentPage; ]5r@`%9
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/** the begin index of the records by the current )~ 0TGy|
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query */ lc$wjK[w[
privateint beginIndex; 2e9.U/9
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/** The default constructor */ bE;c&g
public Page(){ O.DO,]Uh
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} [DZ|Ltv
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/** construct the page by everyPage cLf<YF
* @param everyPage 5ZX
* */ Ew JNpecX
public Page(int everyPage){ <L+1
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this.everyPage = everyPage; T&4f}g/
} I^Dm 3yz
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/** The whole constructor */ k<|}&<h
public Page(boolean hasPrePage, boolean hasNextPage, ^IKT!"J&?
;0U*N &
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int everyPage, int totalPage, nV`U{}x
int currentPage, int beginIndex){ {;N2 &S o
this.hasPrePage = hasPrePage; .DI?-=p|_#
this.hasNextPage = hasNextPage; a^8PB|G
this.everyPage = everyPage; R nwFxFIQ
this.totalPage = totalPage; d%UzQ*s
this.currentPage = currentPage; $A`m8?bY
this.beginIndex = beginIndex; h*R w^5,c
} t#xfso`4o
7=D,D+f
/** ):[}NDmC
* @return !1=*"H%t
* Returns the beginIndex. {-lpYD^k3
*/ =Oq*9=v|
publicint getBeginIndex(){ $
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return beginIndex; d@p#{ -
} RRXp9{x`
:}yT?LIyP
/** ?5jLN&A3 G
* @param beginIndex 1Au+X3
* The beginIndex to set. :0,yq?M
*/ OIJT~Z}
publicvoid setBeginIndex(int beginIndex){ 1+gF fKq
this.beginIndex = beginIndex; sPG500=)
} jo^c>ur
1yZA_x15:
/** *:Rs\QH
* @return WQ}wQ:]
* Returns the currentPage. d]Y;rqjue
*/ NYr)=&)Ke.
publicint getCurrentPage(){ l^d' 8n
return currentPage; yQ$]`hr;
} y|)VNnWM
TZ+ p6M8G
/** ,l6,k<
* @param currentPage 8]Tv1Wc
* The currentPage to set. x1?mE)n]
*/ 0ki- /{;
publicvoid setCurrentPage(int currentPage){ hHhDs>tB
this.currentPage = currentPage; EG`6T
} Q#G xo
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/** )
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* @return DnFzCJ
* Returns the everyPage. *g,ls(r\[
*/ rVqQo`K\
publicint getEveryPage(){ n."n?C'{
return everyPage; $L 8>Ha}
} y^,Q M[ &
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/** ~f(5l.
* @param everyPage ;aV3j/
* The everyPage to set. xa@$cxt
*/ =T,Q7Dh
publicvoid setEveryPage(int everyPage){ ZX` \so,&,
this.everyPage = everyPage; KCW2
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} fj;ZGbg-O
l)vC=V6MG
/** BLyV~
* @return gDVsi
* Returns the hasNextPage. ?W{+[OXs
*/ }q`9U!v
publicboolean getHasNextPage(){ s`_EkFw>Gl
return hasNextPage; aL4^ po
} tg@61V?>
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/** O{_t*sO9q*
* @param hasNextPage ~c35Y9-5
* The hasNextPage to set. e{@RBYX@+c
*/ eO <N/?t
publicvoid setHasNextPage(boolean hasNextPage){ /iFn=pk1?
this.hasNextPage = hasNextPage; qC> tni%
} O hk\P;}
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/**
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* @return xqzeBLU
* Returns the hasPrePage. XnZ$%?$
*/ 1~c\J0h)d
publicboolean getHasPrePage(){ Kf:!tRE
return hasPrePage; EL$DvJ~
} UHZ&7jfl
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/** Eo6N'h >h
* @param hasPrePage VGc*aQYa
* The hasPrePage to set. O~*i_t*i9{
*/ %xlpOR4
publicvoid setHasPrePage(boolean hasPrePage){ F<,pAxl~@
this.hasPrePage = hasPrePage; ?.SGn[
} g:M;S"U3*Y
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/** iAk:CJ{
* @return Returns the totalPage. -xHR6
* [t?tLUg|6
*/ o~~;I
publicint getTotalPage(){ gB'ajX=OA/
return totalPage; 09-8Xzz
} |Gf<Ql_.4
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/** vTK%4=|1}!
* @param totalPage O JcS%-~
* The totalPage to set. eP @#I^_
*/ rE+B}O
publicvoid setTotalPage(int totalPage){ [[ie
this.totalPage = totalPage; &s+l/;3
} ']1n?K=A
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} /*qRbN
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o pTXI*QA
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 tP@NQCo
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个PageUtil,负责对Page对象进行构造: c*)T4n[e
java代码: efXnF*Z
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/*Created on 2005-4-14*/ ,u
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package org.flyware.util.page; 7[1Lh'u
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import org.apache.commons.logging.Log; sF
{,n0<8
import org.apache.commons.logging.LogFactory; Z A(u"T~
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/** :0r,.)
* @author Joa %y RGN
* PFJ$Ia|
*/ Hh%!4_AMw
publicclass PageUtil { 1p}Wj*mc
~m6=s~Vn
privatestaticfinal Log logger = LogFactory.getLog O-(V`BZe
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(PageUtil.class); I\Op/`_=E
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/** UGO#o`.G}
* Use the origin page to create a new page KnG7w^
* @param page ).71gp@&
* @param totalRecords v6*0@/L
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* @return RCWmdR#}V
*/ 8qyEHUN2q
publicstatic Page createPage(Page page, int :A zT=^S
8%9 C<+.R
totalRecords){ |oPRP1F-;e
return createPage(page.getEveryPage(), 1@|+l!rYF
`;UWq{"
page.getCurrentPage(), totalRecords); m{Q
#f\<
} ]}v]j`9m%
O <Rh[Aqn
/** {,%&}kd>
* the basic page utils not including exception U ]<l-~|
qfDG.Zee#
handler 8c9HJ9vk
* @param everyPage ,Wlt[T(.;
* @param currentPage *~^63Nx!
* @param totalRecords %66="1z0@
* @return page 11oNlgY&
*/ "Vp
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publicstatic Page createPage(int everyPage, int =~;~hZj
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currentPage, int totalRecords){ njs:
everyPage = getEveryPage(everyPage); ray3gM%JLj
currentPage = getCurrentPage(currentPage); wK(]E%\
int beginIndex = getBeginIndex(everyPage, pAy4%|(
^-"Iwy
currentPage); z.8/[)
int totalPage = getTotalPage(everyPage, /yI4;:/
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totalRecords); m'"r<]pB*4
boolean hasNextPage = hasNextPage(currentPage, qX@e+&4P0
$?56 i4
totalPage); KfiSQ!{
boolean hasPrePage = hasPrePage(currentPage); ;I4vPh5Q
5MnP6(3$
returnnew Page(hasPrePage, hasNextPage, \GL] I.
everyPage, totalPage,
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currentPage, Tw-NIT)
t.(
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beginIndex); ~[Tcl
} GB$`b'x@S
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privatestaticint getEveryPage(int everyPage){ cr!8Tp;2A
return everyPage == 0 ? 10 : everyPage; ]yPK}u
} F*KQhH7Gf
a&%aads
privatestaticint getCurrentPage(int currentPage){ YZf{."Opj[
return currentPage == 0 ? 1 : currentPage; $)#orZtzr
} RhowhQ) G
4:s!mHcz
privatestaticint getBeginIndex(int everyPage, int $0~_)$i:
D89(u.h
currentPage){ mm`yu$9gbP
return(currentPage - 1) * everyPage; Q$S|L C
} L8 $+%Gvo
Z&Z=24q_
privatestaticint getTotalPage(int everyPage, int &(X-b"2
:W}M$5 |
totalRecords){ qJJ~#W)
int totalPage = 0; )cRP6 =
lT-LOu|
if(totalRecords % everyPage == 0) li)shp)
totalPage = totalRecords / everyPage; &n2dL->*#
else D]5cijO6
totalPage = totalRecords / everyPage + 1 ; idP2G|Z
8CGjI?j
return totalPage; ~&8bVA= .
} 2u^/yl
6tT*b@/_o
privatestaticboolean hasPrePage(int currentPage){ /c52w"WW
return currentPage == 1 ? false : true; gY!#=?/S
} e_t""h4D
lZhd^69y
privatestaticboolean hasNextPage(int currentPage, QR{pph*zn-
LLW\1 cxi
int totalPage){ V.kRV{43
return currentPage == totalPage || totalPage == bZzB\FB~
|$.`4h?
0 ? false : true; +G?nmXG[vj
} @vkO(o
z(_#C
s
m?pm)w
} {Z{!tR?+
G[z4 $0f
;*409P
n0%]dKCB
' lMPI@C6r
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 >]S-a-|Bp
zDx*R3%
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 q, XRb
tc<ly{ 1c
做法如下: %cFqD
& 6
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 FJ(}@U}57
Oa/# 2C~
的信息,和一个结果集List: `78)|a*R.
java代码: ^OnZ9?C{R
]pP:
eg
Zb)pP
/*Created on 2005-6-13*/ !f!HVna
package com.adt.bo; /D&7 \3}
55#s/`gd)^
import java.util.List; 'n4$dv%q
El:&
import org.flyware.util.page.Page; g|rbkK%SoE
af<wUxM0
/** c&a.<e3mL
* @author Joa TW5Pt{X=f
*/ k@/s-^ry3
publicclass Result { v3/l=e?u
( ,!G$~Sy
private Page page; p`2w\P3;)
1^_V8dm)
private List content; #Z>EX?VS:
vo JmNH
/** ?A`8c R=)I
* The default constructor $PE{}`#g
*/ "0]s|ys6<
public Result(){ .P5OUK
super(); T99\R%
} "[tb-$ER
A4`3yy{0-
/** oQ"J>`',
* The constructor using fields G~N$bF^R)
* >0Gdxj]\
* @param page I`
+%ab
* @param content UG:S! w'
*/ ?KMGk]_<
public Result(Page page, List content){ (Ceq@eAlT
this.page = page; moT*r?l
this.content = content; ^I]A@YNni
} L92vb zP
" }oH3L
/** IP=."w
* @return Returns the content. u#r[JF9LP
*/ U,2H) {l/
publicList getContent(){ FvVR \a
return content; ('Doy1L
} ^a{cK
`@)>5gW&p
/**
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* @return Returns the page. +xG
*/ *j"u~ NF
public Page getPage(){ uEX+j
return page; .qAlPe L:
} V4>qR{5
%=EN 3>,
/** x}B_;&>&"_
* @param content (HD8Mm
* The content to set. S?K x:]
*/ |w3b!
public void setContent(List content){ "B3&v%b
this.content = content; yZcnky
} +fRABY5C
7x5wT ?2W
/** OuuN~yC
* @param page ILyI%DA &
* The page to set. {Ne5*HFV
*/ L-z9n@=8\
publicvoid setPage(Page page){ :N>n1tHL;A
this.page = page; :Cdqj0O3u
} PqVz^(Wz
} |rr<4>)X
@:%p#$V
X5w_ }Nhe
=
iXHu
*g
rGIf/=G^r
2. 编写业务逻辑接口,并实现它(UserManager, v{c,>]@
_CImf1
UserManagerImpl) -J'0qN!
java代码: i2&I<:
4157!w'\y
@/f'i9?oM`
/*Created on 2005-7-15*/ >Sc/E}3
package com.adt.service; AJ"a
TnXx;v
import net.sf.hibernate.HibernateException; *-\qO.4\
Xdl7'~k
import org.flyware.util.page.Page; Xt9vTCox
&w'1
import com.adt.bo.Result; @t{`KB+
^
UVlh7w jg
/** b9RJ>K
* @author Joa G<:gNWXd\
*/ wT>~7$=L{
publicinterface UserManager { GJ Takhj3
T]UrKj/iF
public Result listUser(Page page)throws !))!!{
Z66h
HibernateException; dKJ-{LV
s8V:;$ !
} T-a[
A~M .v0
FaQz03N\
7#+>1 "\
;q&uk-
java代码: y%!zXK`cl]
SbXV'&M2AT
Dn[u zY6
/*Created on 2005-7-15*/ LMHiiOs,
package com.adt.service.impl; 3-v&ktD&N'
9}A\BhtiM
import java.util.List; Mi)h<lY
MREB
import net.sf.hibernate.HibernateException; `R
m<1
}U ue}VOA
import org.flyware.util.page.Page; p1!-|Sqq
import org.flyware.util.page.PageUtil; jp880}
3g87i r
import com.adt.bo.Result; @~&1!
import com.adt.dao.UserDAO; 5$ &',v(
import com.adt.exception.ObjectNotFoundException; fLg
:+Ue<B
import com.adt.service.UserManager; 'l $ViNq;
?
J/NYV
/** ib%'{?Q.
* @author Joa 9c{T|+]
*/ oer3DD(
publicclass UserManagerImpl implements UserManager { F60?%gg
=wznkqyhi
private UserDAO userDAO; _sAcvKH
95mwDHbA
/** I<qG{PA
* @param userDAO The userDAO to set. *:?XbtIK u
*/ !>\g[C
publicvoid setUserDAO(UserDAO userDAO){ I{i6e'.jP
this.userDAO = userDAO; 0@wXE\s
} .^8rO,H[
x}~Z[ bx
/* (non-Javadoc) ?tkl
cYB
* @see com.adt.service.UserManager#listUser _'Rg7zHTp-
\3T[Cy|5|
(org.flyware.util.page.Page) cq~~a(IS
*/ v;#0h7qd
public Result listUser(Page page)throws ?OFfU 4
C9 j{:&
HibernateException, ObjectNotFoundException { h{:
]'/@~
int totalRecords = userDAO.getUserCount(); 3QCCX$,
if(totalRecords == 0) qNWSDZQ
throw new ObjectNotFoundException N<XMSt
DD}YbuO7
("userNotExist"); afE8Kqa:H
page = PageUtil.createPage(page, totalRecords); {7Hc00FM
List users = userDAO.getUserByPage(page); )cU$I)
returnnew Result(page, users); Y/T-2)D
} hcoZ5!LvT
T0N6k acl
} )JhB!P(
xy]oj
ee{K5 G
&q +l5L"
qq"0X! w
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 _6 @GT
fo~>y
询,接下来编写UserDAO的代码: Y8c,+D,Ww
3. UserDAO 和 UserDAOImpl: HLPY%VeD
java代码: W4(GI]`_+
a,h]DkD
]"'1-h91
/*Created on 2005-7-15*/ G +AP."M?
package com.adt.dao; a7aj:.wi
UkcH+0o
import java.util.List; OHt^e7\
LTuT"}dT[
import org.flyware.util.page.Page; .yHi"ss3
pTT00`R
import net.sf.hibernate.HibernateException; rdsZ[ii
na@Go@q
/** n<1*cL:8B
* @author Joa u/V&1In
*/ *y', eB
publicinterface UserDAO extends BaseDAO { |Xt6`~iC
.)<l69ZD Z
publicList getUserByName(String name)throws :KqSMuKR
jhJ<JDJ?`
HibernateException; FiSx"o
a:;7'w'
publicint getUserCount()throws HibernateException; *BvdL:t
Eqi;m,)
publicList getUserByPage(Page page)throws K+~1z>&
KwgFh#e
HibernateException; *S?'[PS]1
VQ8Fs/Zt!
} "{kE#`c6<n
f4VdH#eng`
M(I%QD
z]D/Qr
>!%+9@a}
java代码: @bChJl4
y}?PyPz
q=*bcDu
/*Created on 2005-7-15*/ wc-v]$DW
package com.adt.dao.impl; ^=8/I w
vy`
lfbX@
import java.util.List; *j=58d`n
E)wf'x
import org.flyware.util.page.Page; *3s-=.U~
f$vU$>+[
import net.sf.hibernate.HibernateException; 8|Ob7+
import net.sf.hibernate.Query; |nm}E_
&[SFl{fx>-
import com.adt.dao.UserDAO; %V#MUi1
y:_>R=sw
/** u6%\ZK._
\
* @author Joa #XG3{MGX[
*/ X&i;WI
public class UserDAOImpl extends BaseDAOHibernateImpl &D-z|ZjgHi
|"Zf0G
implements UserDAO { ?ZC!E0]
sxuP"4
/* (non-Javadoc) OUwnVAZZ6
* @see com.adt.dao.UserDAO#getUserByName ~-H3]
?771e:>S-
(java.lang.String) b=sY%(2s
*/ r~QE}00@^
publicList getUserByName(String name)throws s 8K.A~5 w
F" M/gy
HibernateException { jp4-w(
String querySentence = "FROM user in class 54WX#/<Yik
G"(aoy,
co
com.adt.po.User WHERE user.name=:name"; W<^t2 j'
Query query = getSession().createQuery *6u2c%^
#>G:6'r
(querySentence); /!>OWh*~
query.setParameter("name", name); 4IY|<
return query.list(); ]3 GO_tL
} Oop6o$k
wmR~e
/* (non-Javadoc) ^ @=4HtA
* @see com.adt.dao.UserDAO#getUserCount() \pI {b9
*/ tG9C(D`G
publicint getUserCount()throws HibernateException { $g VbeQ
int count = 0; iC! 6g|]X
String querySentence = "SELECT count(*) FROM An?#B4:
qW4\t
user in class com.adt.po.User"; o4yl3o
Query query = getSession().createQuery Fx1FxwIJ
A{)pzV25
(querySentence); yeIS} O
count = ((Integer)query.iterate().next !or_CJ8%
g__s(
IJ
()).intValue(); dOaCdnd~
return count; sL\ {.ad5
} Pq{p\Qkj
S{MB$JA
/* (non-Javadoc) U%BtBPL
* @see com.adt.dao.UserDAO#getUserByPage E|RC|Sz=u
"+&pd!\
(org.flyware.util.page.Page) [%6)
*/ xbcmvJrG
publicList getUserByPage(Page page)throws Vep41\g^
vQ2{+5!|
HibernateException { iY,oaC~?"N
String querySentence = "FROM user in class pJl/d;Cyrb
p0CPeH
com.adt.po.User"; a[rb-Z
Query query = getSession().createQuery o F_rC[
D ZZRu8~
(querySentence); _p9"MU&}
query.setFirstResult(page.getBeginIndex()) *""W`x
.setMaxResults(page.getEveryPage()); Y+$]N:\F\
return query.list(); )~"0d;6_
} :#n>Q1}x
Tw*p^rU
} *$;Zk!sEF
%2\Pe 2Z
K/}x'*=
O<@L~S]
q;sZwp<
至此,一个完整的分页程序完成。前台的只需要调用 l:/x&=w
!5[SNr3^
userManager.listUser(page)即可得到一个Page对象和结果集对象 /$\8?<Pc".
't*]6^
的综合体,而传入的参数page对象则可以由前台传入,如果用 ?-9uf\2_
;0?OBUDO
webwork,甚至可以直接在配置文件中指定。 [,ulz4"
glROT@
下面给出一个webwork调用示例: Q]K$yo
java代码: uz$p'Q
l S
p"(&
p__N6a
/*Created on 2005-6-17*/ rL+.3ZO):P
package com.adt.action.user; SGy2&{\Z
IBu\Sh-
import java.util.List; Pn@DHYP
cmCD}Skk
import org.apache.commons.logging.Log; SG0PQ
import org.apache.commons.logging.LogFactory; s0x/2z
import org.flyware.util.page.Page; 6
A#xFPYY{
~mK+Q%G5
import com.adt.bo.Result; K:AP 0Te
import com.adt.service.UserService; ;qWSfCt/^
import com.opensymphony.xwork.Action; 3a ZS1]/
61gyx6v
/** @}{uibLD\
* @author Joa D8Mq '$-
*/ C#)T$wl[E
publicclass ListUser implementsAction{ Hmx.BBz
kG}F/GN?
privatestaticfinal Log logger = LogFactory.getLog 1_c%p#?K
GM)q\Hx{
(ListUser.class); 5U]@
Y?
6zNWDUf
private UserService userService; U:c0s
`/!FZh<
private Page page; 7d|1T'
)z4eRs F|
privateList users; 4UzXTsjM7
E:A!tu$B
/* N{@~(>ee^
* (non-Javadoc) B/n~ $
* e0Gs|c+6
* @see com.opensymphony.xwork.Action#execute() oZl%0Uy?9I
*/ 15aPoxo>
publicString execute()throwsException{ 7kT X
Result result = userService.listUser(page); tuuwoiQ*`
page = result.getPage(); Gui[/iY,F
users = result.getContent(); uf (_<~
return SUCCESS; hJk:&!M=T
} o>Dd1
j
KQw>6)
/** S0r+Y0J]<
* @return Returns the page. g:G5'pZf
*/ +bJ~S:[
public Page getPage(){ pm:- E(3#
return page; aX|(%1r
} (FgX9SV]p9
MpJ<. |h
/** w8J8III\~
* @return Returns the users. e#3RT8u#
*/ Acd@BL*
publicList getUsers(){ h5-yhG
return users; j*4:4B%
} 5tLb
o
|Sua4~yL(
/** 3/]FT#l]i
* @param page y"U)&1 c%
* The page to set. CY[3%7fv
*/ $4)L~g|
publicvoid setPage(Page page){ r=AA
/n<
this.page = page; hk
S:_e=
} Q|S>C%4?
|90X_6(
/** gOah5*Lj
* @param users VhAJ1[k4!
* The users to set. pQC|_T#u
*/ s| Q1;%Tj
publicvoid setUsers(List users){ *n[B Bz
this.users = users; c813NHW
} <X1lq9 lW
*W>, 98
/** Q1|zX@,
* @param userService PDCb(5
* The userService to set. T.-tV[2
*/ zn_#}}e;G
publicvoid setUserService(UserService userService){ uZ>q$
F
this.userService = userService; *">CEQ[MT
} 9d(#/n
} C+5X8
Fr;
's(^
ZW0\_1
V7p
hD3Y
IXR'JZ?fH
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, 'RzO`-dr
u=vBjaN2_w
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 gG}H5uN
M7 kWJ
么只需要: a)Pr&9I
java代码: ;Bzx}7A
7n+,!oJ
oayu*a.
<?xml version="1.0"?> U|\ .)h=
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork >kmgYWG
Oe
:S1 f
1.0//EN" "http://www.opensymphony.com/xwork/xwork- i1m>|[@k
v&WK9F\
1.0.dtd"> V|}9bNF
`YE=B{q
<xwork> d%epM5
) jvI Nb
<package name="user" extends="webwork- 1,Mm+_)B
3
v.8
interceptors"> V3r)u\ o'
MuP>#Vk
<!-- The default interceptor stack name 3]9Rmx
,9_O4O%
--> wAX;)PLg
<default-interceptor-ref <p/2 hHfiD
Md~._@`|K
name="myDefaultWebStack"/> YhfQpe
4 dLnX3 v
<action name="listUser" q5'G]j{,Z
pPo(nH|<
class="com.adt.action.user.ListUser"> ?_A[E]/H
<param ,r]H+vWS
748:*
(O
name="page.everyPage">10</param> udBIEW,`
<result >P\eHR,{-
}Bsh!3D<.
name="success">/user/user_list.jsp</result> lBs-u h
</action> ABkDOG2br
x|dP-E41\
</package> qBh@^GxY),
oSkQ/5hg.
</xwork> bR~(Ry`
_;Xlw{FN^
)z18:C3
vR2);ywX
rwP)TJh"
% -AcA
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 wQjYH!u,YZ
#\QW <I#/
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。 d,(q3
U1E@pDH
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 v{uq
2rf8)8':
n8_X<jIp3
=N{?ll6x7g
:l!sKT?:d!
我写的一个用于分页的类,用了泛型了,hoho /#(IV_Eol
k}&wy
java代码: Ka-o$o[^u`
JehanF[
]Sa#g&}T>
package com.intokr.util; O2pE"8=4Q
.!Z5A9^
import java.util.List; X';qcn_^
c$2kR:
/** '/9j"mIA9$
* 用于分页的类<br> F+Qnf'at1
* 可以用于传递查询的结果也可以用于传送查询的参数<br> +ZW>JjP*
* 3'` &D/n
* @version 0.01 z _\L@b
* @author cheng Q[K$f %>
*/ 1+N'cB!y
public class Paginator<E> { i7r)9^y
privateint count = 0; // 总记录数 @-\=`#C**
privateint p = 1; // 页编号 xZ;eV76
privateint num = 20; // 每页的记录数 Tgtym"=xd
privateList<E> results = null; // 结果 DzE^FY
Y<VX.S2kf
/** eaDZ^Z
Er
* 结果总数 MZ-;'w&Z
*/ 'l~7u({u
publicint getCount(){ Kb<c||2Nh5
return count; ]1d)jWG
} _BJ:GDz>
g_P98_2f.k
publicvoid setCount(int count){ __QnzEF
this.count = count; nA("
cD[,
} mH ju$d
{S9gOg
/** iBbaHU*V
* 本结果所在的页码,从1开始 '[F`!X
* hp2E! C ma
* @return Returns the pageNo. .`+~mQ
Wn
*/ ;
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publicint getP(){ T5ky:{Y(
return p; R$
+RTG:E
} ojf6@p_
<5pNFj}0;X
/** >W-xDzJry
* if(p<=0) p=1 3I( n];
* EHn!ZrQgh
* @param p p qpsa'
*/ ?#: ']q
publicvoid setP(int p){ >TCit1yD
if(p <= 0) G`0{31us
p = 1; rCA!b"C2
this.p = p; UsU
Ri
} 9(S=0<
';Nc;9
/** H@wjZ;R
* 每页记录数量 yy8BkG(
*/ K\xM%O?
publicint getNum(){ XBCHJj]k
return num; r^C(|Vx
} iZdl0;16[
0R\.G1f%
/** Wc+(xk
* if(num<1) num=1 tyW[i8)O}
*/ YB 7A5
publicvoid setNum(int num){ E`^D9:3:)
if(num < 1) 5p!{#r6m
num = 1; E8sM`2z5
this.num = num; 3T]cDVQ_
} !BkE-9v?w
5 cQ]vb
/** jmv=rl>E*
* 获得总页数 J0R{|]W8
*/ 8w[O%
publicint getPageNum(){ >@bU8}rT
return(count - 1) / num + 1; a-,*iK{_u
} -YQS\@?
;k#_/c
/** RbxQTM_:M
* 获得本页的开始编号,为 (p-1)*num+1 e> 9X
*/ 7lwI]/ZH*
publicint getStart(){ ti9e(Jt!O
return(p - 1) * num + 1; bIBF2m4
} iH-,l
2RNee@!JJP
/** p2b~k[
* @return Returns the results. fuA]
y4A
*/ 9x4z m
publicList<E> getResults(){ ivl %%nY'
return results; $04lL/;
} A#I&&qZ
^C^I
public void setResults(List<E> results){ |/l] ]+
this.results = results; |?0MRX0'g
} ;7qzQ{Km
6vNn;-gg.
public String toString(){ %4x0^<k~
StringBuilder buff = new StringBuilder %{r3"Q=;W
DUu:et&c1
(); |-{ Hy(9
buff.append("{"); h+H+>,N8`
buff.append("count:").append(count); 6%6dzZ
buff.append(",p:").append(p); X!z-J>
buff.append(",nump:").append(num); ~1*37 w~
buff.append(",results:").append |*zgX]-+;
HX| p4-L
(results); R -ek O7z
buff.append("}"); [W$Mn.5<s
return buff.toString(); -b?M5P*:
} #| gh
X}3?k<m
} 4x+[?fw
OMjPC_
hC<E4+5.,