Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Mc>]ZAz r
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 TW(rK&
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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 4xk'R[v
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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 =O?<WJoK
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分页支持类: :O-Y67>&
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java代码: oZHsCQ %
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package com.javaeye.common.util; ,
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import java.util.List; @QV|<NeH
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publicclass PaginationSupport { \|BtgT *$b
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publicfinalstaticint PAGESIZE = 30; poGF
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privateint pageSize = PAGESIZE; 0V`s 3,k
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privateList items; {(U?)4@
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privateint totalCount; cx_FtD
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privateint[] indexes = newint[0]; ):;
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privateint startIndex = 0; sDTCV8"w
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public PaginationSupport(List items, int lZ.x@hDS
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totalCount){ v:
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setPageSize(PAGESIZE); @G+Hrd6
setTotalCount(totalCount); ;:,hdFap
setItems(items); !*HH5qh6
setStartIndex(0); <k-&Lh:o3
} j$'L-kK+
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public PaginationSupport(List items, int vQ>x5\r5O_
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totalCount, int startIndex){ yoGe^gar
setPageSize(PAGESIZE); ~KHGh29
setTotalCount(totalCount); -'BC*fV r
setItems(items); Ox7v*[x'
setStartIndex(startIndex); WF,<7mx=-
} JV(qTb W
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public PaginationSupport(List items, int _U( b
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totalCount, int pageSize, int startIndex){ EtvZk9d6h*
setPageSize(pageSize); Pz7{dQqjk#
setTotalCount(totalCount); (JHzwI8+
setItems(items); {G&*\5W
setStartIndex(startIndex); 6SI`c+'@5
} z )s{>^D
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publicList getItems(){ <@6K(
return items; teH.e!S
} *yKw@@d+p
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publicvoid setItems(List items){ o7 ^t-
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this.items = items; (oTtnQ""+
} d2`m0U
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publicint getPageSize(){ H&\[iZ|-N
return pageSize; KU# w%
} H_RV#BW&
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publicvoid setPageSize(int pageSize){ .RFijr
this.pageSize = pageSize; *"Yz"PK
} IaMZPl
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publicint getTotalCount(){ ,{==f7|w
return totalCount; f'&30lF
} reseu*5
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publicvoid setTotalCount(int totalCount){ #^%HJp^
if(totalCount > 0){ YHBH9E/B
this.totalCount = totalCount; I/4:SNha
int count = totalCount / q2 K@i*s
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pageSize; r+%:rFeX
if(totalCount % pageSize > 0) %+Hhe]J ld
count++; zURxXo/\V
indexes = newint[count]; &Ui*w%
for(int i = 0; i < count; i++){ r9nH6 Md\
indexes = pageSize * _+Tq&,_:o
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} p1~u5BE7O
}else{ }]O*
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this.totalCount = 0; fLkZ'~e!
} tuH8!.
} #9{N[t
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publicint[] getIndexes(){ -Pds7}F8
return indexes; PF=BXY1<UL
} A"|y<
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publicvoid setIndexes(int[] indexes){ obA}SF
this.indexes = indexes; 9vIqGz-o
} t!}QG"ma
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publicint getStartIndex(){ \l)Jb*t
return startIndex; <X>lA
} Tx+!D'>
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publicvoid setStartIndex(int startIndex){ tYb8a
if(totalCount <= 0) a^:on?:9
this.startIndex = 0; JH3$G,:zM
elseif(startIndex >= totalCount) bogw /)1
this.startIndex = indexes %{M_\Ae#
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[indexes.length - 1]; ]rwHr;.
elseif(startIndex < 0) Z8vMVo
this.startIndex = 0; ai,\'%N
else{ jhRg47A
this.startIndex = indexes %@C(H%obWd
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[startIndex / pageSize]; <jt_<p
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} WY>r9+A?W
} *[VO03
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publicint getNextIndex(){ +#* F"k(
int nextIndex = getStartIndex() + %E<.\\^%
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pageSize; 4o/}KUu(*
if(nextIndex >= totalCount) ?=u/&3Cw
return getStartIndex(); ,K/l;M5I
else 8|]r>L$Wk
return nextIndex; ^nO0/nqz]
} 8>R 75dw
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publicint getPreviousIndex(){ 6[.#B!;9
int previousIndex = getStartIndex() - 0iKSUwps
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pageSize; 8m prK`p
if(previousIndex < 0) EN,PI~~F
return0; Fx@ovI- 5
else 0f_+h %%=
return previousIndex; d#tqa`@~
} =D>,s)}o3;
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} ol[sX=5 *
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抽象业务类 [TW?sW^0
java代码: z`Jcpt
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/** K'6NW:zp~
* Created on 2005-7-12 k4C3SI*`4
*/ bHKTCPf
package com.javaeye.common.business; I>bO<T`
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import java.io.Serializable; u# TNW.
import java.util.List; Sux/='
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import org.hibernate.Criteria; _\2Ae\&c
import org.hibernate.HibernateException; @%^JB
import org.hibernate.Session; IgmCZ?l&0
import org.hibernate.criterion.DetachedCriteria; i-jrF6&
import org.hibernate.criterion.Projections; w *pTK +
import SzTa[tJ+
m{w'&\T
org.springframework.orm.hibernate3.HibernateCallback; '+s ?\X4VC
import u\y$<
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org.springframework.orm.hibernate3.support.HibernateDaoS ke)}JU^"
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upport; u\AL`'v
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import com.javaeye.common.util.PaginationSupport; U [R[VY7
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public abstract class AbstractManager extends kf:Nub+h t
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HibernateDaoSupport { 5$?)f&M
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privateboolean cacheQueries = false; FokSg[)5
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privateString queryCacheRegion; Y6E0-bL@Fe
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publicvoid setCacheQueries(boolean AX] cM)w
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cacheQueries){ "(YfvO+
this.cacheQueries = cacheQueries; edL sn>\*#
} ]@6L,+W"
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publicvoid setQueryCacheRegion(String JKF/z@Vbe\
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queryCacheRegion){ 0O!A8FA0
this.queryCacheRegion = 7$JOIsM
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queryCacheRegion; s}<i[hY>
} ;r BbLM`
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publicvoid save(finalObject entity){ xqpq|U
getHibernateTemplate().save(entity); lyzM?lK-
} %w;wQ_
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publicvoid persist(finalObject entity){ jfU$qo!gi
getHibernateTemplate().save(entity); ;3\'}2^|l
} v[\GhVb
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publicvoid update(finalObject entity){ *pYawT
getHibernateTemplate().update(entity); 0C4Os p
} N *,[(q
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publicvoid delete(finalObject entity){ xQ!
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getHibernateTemplate().delete(entity); q\/xx`L
} p+;;01Z+_
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publicObject load(finalClass entity, z
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finalSerializable id){ F8&L'@m9>
return getHibernateTemplate().load Z~ K} @
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(entity, id); sWKv>bx
} %3yrX>Js
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publicObject get(finalClass entity, 3uL$+F
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finalSerializable id){ $S^rKp#
return getHibernateTemplate().get 44pVZ5c
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(entity, id); p\}!uS4 (
} ab[V->>%
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publicList findAll(finalClass entity){ 65GC7 >[
return getHibernateTemplate().find("from *,
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" + entity.getName()); w+{{4<+cd
} .uB[zJc
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publicList findByNamedQuery(finalString rS0#]Gg
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namedQuery){ X{iidTW`xv
return getHibernateTemplate _MTvNs
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().findByNamedQuery(namedQuery); N6v*X+4JH
} nyZ?m
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publicList findByNamedQuery(finalString query, ^y~oXS(
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finalObject parameter){ iig&O(,
return getHibernateTemplate OA7=kH@3c
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().findByNamedQuery(query, parameter); M#yUdl7d
}
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publicList findByNamedQuery(finalString query, oTA'=<W?D
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finalObject[] parameters){ `Mo%)I<`=
return getHibernateTemplate tfv@
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().findByNamedQuery(query, parameters); tAb3ejCo?
} M<@9di7c
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publicList find(finalString query){ '=IuwCB|;
return getHibernateTemplate().find ik0w\*
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(query); mW)"~sA
} $-)y59w"
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publicList find(finalString query, finalObject %;` 3I$
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parameter){ ezd@>(hJ
return getHibernateTemplate().find 'eoI~*}3WQ
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(query, parameter); s3M#ua#mX
} *kDV ^RBfq
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public PaginationSupport findPageByCriteria 16I(S
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(final DetachedCriteria detachedCriteria){ |nO}YU\E
return findPageByCriteria 5gPAX $j H
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); xX])IZD
} OZh+x`' #
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public PaginationSupport findPageByCriteria \y/+H
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(final DetachedCriteria detachedCriteria, finalint c>Ljv('bj
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startIndex){ m<22E0=g
return findPageByCriteria 0M>%1*
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(detachedCriteria, PaginationSupport.PAGESIZE, ?rV c}
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startIndex); z9KsSlS ^
} Va'K~$d_
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public PaginationSupport findPageByCriteria %K]nX#.B&
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(final DetachedCriteria detachedCriteria, finalint O~&l.>??
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pageSize, 8%#uZG\}
finalint startIndex){ QfM*K.7Sl
return(PaginationSupport) Yui:=GgUrr
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getHibernateTemplate().execute(new HibernateCallback(){ -.WVuc`
publicObject doInHibernate `P4qEsZE>`
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(Session session)throws HibernateException { )+9D$m=P;
Criteria criteria = 3/@'tLtN
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detachedCriteria.getExecutableCriteria(session); g^En6n)
int totalCount = jW",'1h<n
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((Integer) criteria.setProjection(Projections.rowCount p:ST$ 1 K
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()).uniqueResult()).intValue(); YKvFZH)
criteria.setProjection |@-WC.
7"JU)@ U]
(null); @]#+`pZ4A
List items = TJ5{Ee GV
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criteria.setFirstResult(startIndex).setMaxResults 1y"37;x
qc'tK6=jp
(pageSize).list(); P [nWmY
PaginationSupport ps = PvT8XSlTx!
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new PaginationSupport(items, totalCount, pageSize, -{b1&
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startIndex); 16Gv?
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return ps; pmW=l/6+V3
} -;`W"&`ss
}, true); JcVq%~{M
} *E)Y?9u"
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public List findAllByCriteria(final 0RSa{iS*A
)#ujF~w>
DetachedCriteria detachedCriteria){ nG%j4r ;
return(List) getHibernateTemplate MM8)yCI
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().execute(new HibernateCallback(){ NJtB ;
publicObject doInHibernate S~Hj.
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(Session session)throws HibernateException { : }IS=A
Criteria criteria = TQ2Tt"
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detachedCriteria.getExecutableCriteria(session); M{4_BQ4$
return criteria.list(); Ul'G
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} er#=xqUY
}, true); %ej"ZeM
} T+ t-0k
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public int getCountByCriteria(final j{Fo 6##
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DetachedCriteria detachedCriteria){ d?P
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Integer count = (Integer) r4lG 5dV
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getHibernateTemplate().execute(new HibernateCallback(){ mHMej@
publicObject doInHibernate 4yM8W\je
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(Session session)throws HibernateException { ^9RBG#ud
Criteria criteria = Mvh_>-i
<FK><aA_i*
detachedCriteria.getExecutableCriteria(session); -ur]k]R
return ^>p [b
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criteria.setProjection(Projections.rowCount MnI $%
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()).uniqueResult(); ybG)=0
} aS7zG2R4H
}, true); <<1oc{i
return count.intValue(); W<L6,
} u@EM,o
} @ih}x
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用户在web层构造查询条件detachedCriteria,和可选的 c" 7pf
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 k#(cZ
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PaginationSupport的实例ps。 ]EnaZWyO]
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ps.getItems()得到已分页好的结果集 dE]"^O#Mc
ps.getIndexes()得到分页索引的数组 's?F ip
ps.getTotalCount()得到总结果数 Fzs'@*
ps.getStartIndex()当前分页索引 n4 @a`lN5g
ps.getNextIndex()下一页索引 1znV>PO!
ps.getPreviousIndex()上一页索引 +_dYfux
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 I uj=d~|>
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 \cP'#jZz
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一下代码重构了。 0Zh
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我把原本我的做法也提供出来供大家讨论吧: k)V%.Eobf
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首先,为了实现分页查询,我封装了一个Page类: E$Pjp oQTf
java代码: QCfpDE}
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/*Created on 2005-4-14*/ A9Wqz"[
package org.flyware.util.page; #L:P
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/** [=6~"!P}
* @author Joa dMmka
* 9[{>JRm.
*/ 5MY}(w
publicclass Page { ;sR6dT)
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/** imply if the page has previous page */ E ' JC
privateboolean hasPrePage; (Q8?)
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/** imply if the page has next page */ LDEW00zL
privateboolean hasNextPage; qf`xH"$
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/** the number of every page */ QlYs7zZ
privateint everyPage; E(!6n= qR
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/** the total page number */ (}1v^~FXj
privateint totalPage; rk,1am:cg
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/** the number of current page */ &s^>S?L-
privateint currentPage; JkDPuTXD
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/** the begin index of the records by the current <cv2-?L{
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query */ #} ~p^ 0
privateint beginIndex; CQjZAv
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/** The default constructor */ |@ZqwC=
public Page(){ [j}7 @Mr`\
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} noh|/sPMD
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/** construct the page by everyPage ;eW'}&|LV
* @param everyPage H*{k4
* */ K@jSr*\'
public Page(int everyPage){ }kCn@
this.everyPage = everyPage; K 5qLBz@U
} 2rO)qjiH
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/** The whole constructor */ *hZ~i{c,7
public Page(boolean hasPrePage, boolean hasNextPage, UOu6LD/|h
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int everyPage, int totalPage, +#*&XX5A#?
int currentPage, int beginIndex){ 0Q$~k
this.hasPrePage = hasPrePage; ?..i 4
this.hasNextPage = hasNextPage; EvqUNnjR
this.everyPage = everyPage; CO:*x,6au
this.totalPage = totalPage; 3q#"i&
this.currentPage = currentPage; #u8*CA9
this.beginIndex = beginIndex; "J P{Q
} :/@k5#DY
m|[\F#+C
/** QJ a4R
* @return U~{Sa+
* Returns the beginIndex. '!wPnYT@D
*/ ~>#LOT `
publicint getBeginIndex(){ H_?;h-Y]
return beginIndex; Y_[g_
} k;;nE o~6
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/** +R
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* @param beginIndex DC|xilP1O
* The beginIndex to set. 5jn$7iE`
*/ BgJkrv7~
publicvoid setBeginIndex(int beginIndex){ {A]k%74-a
this.beginIndex = beginIndex; oMh~5
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} 20rN,@2<
M8 iEVJ
/** 5mI?pfm
* @return CgVh\4,a
* Returns the currentPage. x*unye7
*/ K4j@j}zK9I
publicint getCurrentPage(){ ?_VRfeztw
return currentPage; <K.Bq]
} <TI3@9\qXE
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/** z@!^ow)`J
* @param currentPage B;eW/#`
* The currentPage to set. tgO+*q5B
*/ J3H.%m!V
publicvoid setCurrentPage(int currentPage){ xik`W!1S
this.currentPage = currentPage; YO)')&
} ':,>eL#+uV
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/** ^pJ0nY#c
* @return McEmd.S<n
* Returns the everyPage. b\1+kB/8
*/ M$,Jg5Dc
publicint getEveryPage(){ M} O[`Fx{W
return everyPage; ,q8(]n4
} 65lOX$*{-
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/** :tKbz
nd/
* @param everyPage Tv`_n2J`2
* The everyPage to set. DXKyRkn6e
*/ w'd.;
publicvoid setEveryPage(int everyPage){ DeA @0HOxh
this.everyPage = everyPage; -<O JqB
} `/c7h16
AvZXRN1:'
/** e d_m +NM
* @return gC0;2
* Returns the hasNextPage. LxB&7
*/ iNt 4>
publicboolean getHasNextPage(){ ^Ss<X}es-
return hasNextPage; HP;|'b
} P!5Z]+B#
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/** ?F1wh2oq
* @param hasNextPage PDhWFF
* The hasNextPage to set. 0X.TF
*/ mLJDxh'B
publicvoid setHasNextPage(boolean hasNextPage){ Y7-*2"!
this.hasNextPage = hasNextPage; Cgo9rC~]
} L4~
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/** N50fL
* @return (e(Rr4
* Returns the hasPrePage. 3i6h"Wu`n
*/ WI6(#8^p
publicboolean getHasPrePage(){ YtMlqF
return hasPrePage; Uh*@BmDA
} "tKNlHBu'
+uELTHH=
/** xLZ bU4
* @param hasPrePage |Hfl&3
* The hasPrePage to set. qT$)Rb&
*/ $}db /hY*
publicvoid setHasPrePage(boolean hasPrePage){ |f<9miNu
this.hasPrePage = hasPrePage; ER_ 3'
} -rO*7HO
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/** l/M[am
* @return Returns the totalPage. kB
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* W=3? x
*/ ]'tJ
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publicint getTotalPage(){ )L >Q;'
return totalPage; lr0M<5d=p
} &5d\~{;
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/** pD[pTMG@$
* @param totalPage $D}"k!H
* The totalPage to set. hox< vr4
*/ _\UIc;3Gl
publicvoid setTotalPage(int totalPage){ >%l:Dw\A:
this.totalPage = totalPage; L$kgK# T
} e:BDQU
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} **n y!
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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 me:iQ.g
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个PageUtil,负责对Page对象进行构造: l/QhD?)9
java代码: d+e0;!s~O
I3PQdAs~&h
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/*Created on 2005-4-14*/ >MPa38
package org.flyware.util.page; uRpBeH]Z"
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import org.apache.commons.logging.Log; 9$wAm89
import org.apache.commons.logging.LogFactory; ;t!9]1
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/** {"t5\U6cKM
* @author Joa 3e *-\TP-
* J)Ol"LXV
*/ <%&_#<C)
publicclass PageUtil { _ ~[M+IO
gs>A=A(VYf
privatestaticfinal Log logger = LogFactory.getLog `,P
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(PageUtil.class); d#8e~
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/** !=y Q)l2
* Use the origin page to create a new page kT2Wm/L
* @param page K[]K53Nk
* @param totalRecords ]'g:B p
* @return 1yS&~
y?a
*/ 0MrN:M2B
publicstatic Page createPage(Page page, int =ajLa/m'
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totalRecords){ g>T
return createPage(page.getEveryPage(), B:nK)"{
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page.getCurrentPage(), totalRecords); ST%
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} rs_h}+6"s
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/** $+jy/:]D
* the basic page utils not including exception G
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handler D2]ZMDL.
* @param everyPage |]tZ hI"3<
* @param currentPage Q.E_:=*H
* @param totalRecords 7>&1nBh. f
* @return page 'kEG.Oq7
*/ Qt~B#R.
V
publicstatic Page createPage(int everyPage, int NWaO_sm
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currentPage, int totalRecords){ LD_M 3
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everyPage = getEveryPage(everyPage); U{HML|
currentPage = getCurrentPage(currentPage); %"+4
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int beginIndex = getBeginIndex(everyPage, )#PtV~64
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currentPage); {$|/|*
int totalPage = getTotalPage(everyPage, jzMg'z/@J
--A&TV
totalRecords); mw"}8y
boolean hasNextPage = hasNextPage(currentPage, u GAh7Sop
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totalPage); ofK='G.
boolean hasPrePage = hasPrePage(currentPage); fp tIc#4
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returnnew Page(hasPrePage, hasNextPage, tUv3jq)n%
everyPage, totalPage, Oq}ip
currentPage, gs fhH0
y;r"+bS8
beginIndex); J^h'9iQpi
} MHFaSl
0$QIfT)
privatestaticint getEveryPage(int everyPage){ 4i`S+`#
return everyPage == 0 ? 10 : everyPage; -f 4>MG
} 0-GKu d
3a9u"8lG
privatestaticint getCurrentPage(int currentPage){ 3>M.]w6{
return currentPage == 0 ? 1 : currentPage; 1J&\,f&
} W} Zb~[,
/3F<=zi kO
privatestaticint getBeginIndex(int everyPage, int #'8)u)!
g&kH'fR8
currentPage){ 1\IZcJ {
return(currentPage - 1) * everyPage; bOe<\Y$
} m#;.yR
)tvc/)&A}
privatestaticint getTotalPage(int everyPage, int PU"S;4m
-F1P28<?
totalRecords){ CWBbSGk
int totalPage = 0; ET3,9+Gj
7N6zqjIB
if(totalRecords % everyPage == 0) ,O2q+'&
totalPage = totalRecords / everyPage; [WYJrk.
else ;M-,HK4=
totalPage = totalRecords / everyPage + 1 ; 8;0^'Qr8
sSV^5
return totalPage; GBW 7Y
} $82zy q
kR_E6Fl
privatestaticboolean hasPrePage(int currentPage){ jOtzx"/)rE
return currentPage == 1 ? false : true; C`pan /t
} PK8V2Ttv
oW8;^u
privatestaticboolean hasNextPage(int currentPage, "(N-h\7Ex9
A>5S]
int totalPage){ 9c%(]Rn:
return currentPage == totalPage || totalPage == 'h k @>"
sv@}x[L
0 ? false : true; 9a-]T=5Ee
} w2'
3S#nZ
=O;eY ?
N*?
WUn9]
} _4O[[~
,znL,%s
~;` fC|)
pc^E'h:
=g1 D;
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 R+C+$?4NG
\#HL`R"
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 Xp.|.)Od
V.+DP
做法如下: gZ=)qT]Pj
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 cS+?s=d
s9=pV4fA~w
的信息,和一个结果集List: m79m{!q$-
java代码: S".owe$\
+ESX.Vel
bXk:~LE
/*Created on 2005-6-13*/ H)-L%l|9
package com.adt.bo; [sjrb?Xd
TZ)(ZKX*R
import java.util.List; !Mm+bWn=mB
}6F_2S3c
import org.flyware.util.page.Page; G;87in ,}
%9fa98>
/** Ey
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* @author Joa <#:Ebofsn
*/ 'cWlY3%t
publicclass Result { Sz^TGF
Ov F8&*A
private Page page; }S1Z>ZA5
ytuWT,u
private List content; [J(@$Qix
BHIZHp
/** R V_MWv
* The default constructor 1==P.d(
*/ 30wYc &H
public Result(){ ZP]2/;h
super(); vY8WqG]
} 5M/%%Ox
qJe&jLZa
/** ZdJVs/33Vn
* The constructor using fields %`t]FV^#
* !8H!Fj`|j
* @param page Off: ~
* @param content )eIz{Mdp=
*/ 8,Q.t7v
public Result(Page page, List content){ d|D'&&&c
this.page = page; nA{ncTg1\
this.content = content; 8Iqk%n~(
} 3"2<T^H]
>vNk kxWyQ
/** 8 RzF].)
* @return Returns the content. $Sc08ro
*/ &Nj:XX;X
publicList getContent(){ 59"Nn\}3gE
return content; +qu@dU0\`|
} mYsuNTx!.
=l?"=HF
/** 6w:g77SH)%
* @return Returns the page. 8H$@Xts
*/ oK(W)[u
public Page getPage(){ VygXhh^7\
return page; GT1 X
} ~]i]kU
gn4g 43
/** 'w |s*5
* @param content ]ZU:%Qhu
* The content to set. qU
/Wg
*/ HC<BGIgL
public void setContent(List content){ 4u{E D(
this.content = content; }y-AoG
} Xoa<r9
)=SYJ-ta<
/** (0+ GLI8
* @param page ^0,&R\e+
* The page to set. G+\~rl
*/ ~n]2)>6
publicvoid setPage(Page page){ M%Kx{*aw&
this.page = page; +'YSpJ
} S|u1QGB
} Ow&'sR'CX
UU:QK{{E
w!GU~0~3[
v'2OHb#
RE*S7[ge
2. 编写业务逻辑接口,并实现它(UserManager, +XaO?F[c
_QtQPK\+
UserManagerImpl) 1H2u,{O
java代码: 5GWM
)vrZg
nbkky.e
e^l+#^fR
/*Created on 2005-7-15*/ Q/9vDv
package com.adt.service; /EAQ.vxI
y [7xK}`_
import net.sf.hibernate.HibernateException; ?RjKP3P
kod_ 1LD
import org.flyware.util.page.Page; MdTd$ 4J3
f+W[]KK*PW
import com.adt.bo.Result; 0T{Y_IG
x@bl]Z(ne/
/** 0_xcrM
* @author Joa !E.lyz
*/ NB6h/0*v
publicinterface UserManager { sB1tce
gu%'M:Xe
public Result listUser(Page page)throws .^+$w$
$!3t$-TSD
HibernateException; u C8T!z
EA{*%9 A
} Q8/0Cb/
"OAZ<
O=?X%m #
{,mRMDEy
2n+XML
java代码: PHL@1K{)
hy`)]>9z~
Q1&dB{L
/*Created on 2005-7-15*/ V$F.`O!hfi
package com.adt.service.impl; \rnG 1o
*L8HC8IbH
import java.util.List; 0*M}QXt
YaZ"&i
import net.sf.hibernate.HibernateException; ML"P"&~u6
7wEG<,D
import org.flyware.util.page.Page; %[CM;|?B4
import org.flyware.util.page.PageUtil; T-8nUo}i
w3cK:
C0
import com.adt.bo.Result; 5Cyjq0+
import com.adt.dao.UserDAO; hBSJEP
import com.adt.exception.ObjectNotFoundException; 2}C>{*}yQ
import com.adt.service.UserManager; !l~aRj-WZ
xi^e =:;`
/** H 1X]tw.
* @author Joa #]/T9:
*/ q _|5,_a
publicclass UserManagerImpl implements UserManager { O!+5As
7Cp_41._
private UserDAO userDAO; =9@yJ9c-
O;t?@!_
/** ga9:*G!b{)
* @param userDAO The userDAO to set. myX0<j3G5
*/ xyWdzc](p
publicvoid setUserDAO(UserDAO userDAO){ Bzt`9lg
this.userDAO = userDAO; :Aiu!}\
} Y rnqi-P
!T(Omve)
/* (non-Javadoc) RYaofW
* @see com.adt.service.UserManager#listUser 2,nCGSfc
^#nWgo7{7
(org.flyware.util.page.Page) 3+uoK f[
*/ tX}S[jdq
public Result listUser(Page page)throws cHct|Z
u
m6<0 hP
HibernateException, ObjectNotFoundException { f+~!s 2uw
int totalRecords = userDAO.getUserCount(); K8c#/o
if(totalRecords == 0) PdBhX
throw new ObjectNotFoundException oF^hq-xcP
?tQv|x
("userNotExist"); ^C|9K>M
page = PageUtil.createPage(page, totalRecords); @23x;x
List users = userDAO.getUserByPage(page); =@
returnnew Result(page, users); }"k(kH
}
,^C;1ph
r0bPaAKw
} uelTsn
1e} 3L2rC
qEz'l'%(
AE
_~DZ:%c
E=trJge
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 2oASz|
XLxr~Yo
询,接下来编写UserDAO的代码: h!GixN?
3. UserDAO 和 UserDAOImpl: }dl(9H=4
java代码: KVy5/A/8c
'|T=
hZJqo + s
/*Created on 2005-7-15*/ zy;w07-)
package com.adt.dao; D*,H%xA
u)pBFs<dn
import java.util.List; WQL`;uIX
WE]^w3n9
import org.flyware.util.page.Page; jXZNr
"Fiv
]^
import net.sf.hibernate.HibernateException; /d'u1FnA=
,cEcMaJ
/** c*Nbz,:
* @author Joa [NcOk,
*/ ;v\n[
publicinterface UserDAO extends BaseDAO { :g";p.~=
tEs$+b
publicList getUserByName(String name)throws p6)UR~9Rs
m
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HibernateException; CG;D (AWR;
)`^:G3w
publicint getUserCount()throws HibernateException; *Rd&4XG
5WYU&8+]{:
publicList getUserByPage(Page page)throws M-gjS6c\3
DBRJtU!5x
HibernateException;
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D6WsEd>
} T\>=o]
W]OT=6u8o
(Q+3aEUE
(tv h9o
cw\a,>]H
java代码: !w Bmf&=
Xk$lQMwZ
U<b!$"P9
/*Created on 2005-7-15*/ R7i*f/m
package com.adt.dao.impl; |sh U
w6_}]
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import java.util.List; NL 37Y{b
TfPx
import org.flyware.util.page.Page; 51vK>
6X7_QBC)
import net.sf.hibernate.HibernateException; p* @L1
import net.sf.hibernate.Query; V_* ^2c)
bBX~ZWw
import com.adt.dao.UserDAO; A?/?9Gr
& \m\QI
/** jo^*R'}
* @author Joa ,o)MiR9-[A
*/ ? &O$ayG77
public class UserDAOImpl extends BaseDAOHibernateImpl >@" j9
w9%gaK;
implements UserDAO { l-
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5
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/* (non-Javadoc) m_B5M0},
* @see com.adt.dao.UserDAO#getUserByName O,cx9N
:.cX3dP@
(java.lang.String) gT.-Cf{
*/ 1 wG1\9S
publicList getUserByName(String name)throws Ij+zR>P8=\
?P5D!b:(
HibernateException { $sJn:
8z
String querySentence = "FROM user in class 0`W~2ai
fp7Qb $-A
com.adt.po.User WHERE user.name=:name"; <7GK *I
Query query = getSession().createQuery $spf=t"nh
bbJa,}R
(querySentence); F,sT[C
query.setParameter("name", name);
)nY/ RO
return query.list(); URAipLvN
} ^!9b#Ja
TDoYp
/* (non-Javadoc) C$bK!]a
* @see com.adt.dao.UserDAO#getUserCount() L8W3Tpi&(
*/ 4Qdg t*
publicint getUserCount()throws HibernateException { *%O1d.,
int count = 0; -K
jCPc
String querySentence = "SELECT count(*) FROM ~K[rQ
c|7Pnx%gT
user in class com.adt.po.User"; \o^+'4hq<5
Query query = getSession().createQuery qb_V
,b9
'/j`j>'!^
(querySentence); )L{\k$r!EM
count = ((Integer)query.iterate().next +,MzD'(D
U0rz 4fxc
()).intValue(); G2A pm`/ y
return count; +|.#<]GA
} pk/#+r;
_ReQQti[
/* (non-Javadoc) t~AesHZpk
* @see com.adt.dao.UserDAO#getUserByPage j<!$ug9VA
gFKQm(0g2
(org.flyware.util.page.Page) |9y&;3
*/ +LUL-d
publicList getUserByPage(Page page)throws Xm*Dh#H
5`+*({
HibernateException { <W?,n%
String querySentence = "FROM user in class L^=>)\R2$[
>$?Z&7Lv
com.adt.po.User"; !B\\:k]aO^
Query query = getSession().createQuery
R+m{nO~r
dI>oHMC
(querySentence); b#P8Je`;9
query.setFirstResult(page.getBeginIndex()) ENGw <
.setMaxResults(page.getEveryPage()); 3{%/1>+x5
return query.list(); 8\yH7H
} @1>83-p"X
Kg.E~
} ]\jhtC=2
\F>
*d!^C
RH`m=?~J,
#&@&BlIe
83S],L
至此,一个完整的分页程序完成。前台的只需要调用 ZK13[_@9
pG"
4qw
userManager.listUser(page)即可得到一个Page对象和结果集对象 {ng
R ~cc]kp0
的综合体,而传入的参数page对象则可以由前台传入,如果用 ;w1h)
, vky
webwork,甚至可以直接在配置文件中指定。 N%T-Q9k
k<:!^_3H
下面给出一个webwork调用示例:
ic3qb<2
java代码: .D7\Hao
o]]Q7S=
Qc3!FW<26
/*Created on 2005-6-17*/ a#kZY7s
package com.adt.action.user; =^{^KHzIl3
{L8SDU{P
import java.util.List; t$}+oCnkv
\>\w-ty[(
import org.apache.commons.logging.Log; :cOwTW?Fj
import org.apache.commons.logging.LogFactory; o77HRX
import org.flyware.util.page.Page; AD8~
5B(|!Xq;I
import com.adt.bo.Result; lRO4-
y
import com.adt.service.UserService; N%^mR>.`
import com.opensymphony.xwork.Action; nrZv>r
n%ld*EgY
/** BkIvoW_
* @author Joa 2[WQq)\
*/ `E}2|9
publicclass ListUser implementsAction{ 0a(*/u
jL2f74?1
privatestaticfinal Log logger = LogFactory.getLog <1hwXo
wv1?v_4
(ListUser.class); R,y8~D
,x_g|J _Y
private UserService userService; s$RymM
3 \kT#nr
private Page page; 1pcSfN :"1
eNXpRvY
privateList users; &jj\-;=~Ho
EK#w: "
/* +|o-lb
* (non-Javadoc) #BM *40tch
* hR. EZ|.
* @see com.opensymphony.xwork.Action#execute() L:'Y#VI{
*/ #'"h+[XY
publicString execute()throwsException{ Cu!4ha.e`
Result result = userService.listUser(page); *A_
page = result.getPage(); :pNZQX
users = result.getContent(); YXBS!89m
return SUCCESS; Phx/9Kk
} +[z(N
tl#hCy
/** "b2Mk-qP
* @return Returns the page. bG\1<:6B
*/ =lVfrna
public Page getPage(){ mTcLocx
return page; F@?QVdY1q7
} RPLr7Lb
EQ7cK63
/** '"I"D9;9
* @return Returns the users. ib&
|271gG
*/ ]QpR>b=[j
publicList getUsers(){ D:){T>
return users; x!G\-2#
} G|H\(3hHLZ
b>fDb J0
/** 4
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* @param page fDqlN`P@
* The page to set. J|3CG;+
*/ v^KJU
+
publicvoid setPage(Page page){ @Wdnc/o]
this.page = page; bv|v9_i
} 5*ABw6'6
ULsz<Hj
/** D b(a;o
* @param users w}7`Vas9
* The users to set. mQ1QJ_;
*/ 6~D:O?2
publicvoid setUsers(List users){ *mBn''a"*
this.users = users; mB_ba1r
} $z`
jR*
@ /c{gD
/** k
\]@
* @param userService x~KS;hA
* The userService to set. R(x%<I
*/ vW~_+:),e
publicvoid setUserService(UserService userService){ X~W5Z(w(O
this.userService = userService; A7ck-9dT/L
} g,x$z~zU{
} idz6m]{~yT
o'R_kadN[T
hydn" 9;
I7]45pF
r`6XF
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, nj)M$'
C%G-Ye|@
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 gNe{P~ $=
MQp1j:CK
么只需要: vChkSY([
java代码: aiU n
bP
%lEPFp
9KCnitU
<?xml version="1.0"?> D*_ F@}=
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork >uxak2nM-
&a1agi7M
1.0//EN" "http://www.opensymphony.com/xwork/xwork- Ho*S>Y
+X.iJ$)
1.0.dtd"> +U@P+;
Bxz{rR0XV
<xwork> R"K{@8b
{hVSVx8ZL
<package name="user" extends="webwork- wG19NX(
bm(0raugs
interceptors"> l,pq;>c9a
Fx)]AJ~[t
<!-- The default interceptor stack name <K|_M)/9
Sd}fse
--> (r:WG!I,
<default-interceptor-ref b-%7@j
x4Eq5"F7}
name="myDefaultWebStack"/> >P+V!-%#
rcNM,!dZ
<action name="listUser" hF!yp7l;
+qjW;]yxP
class="com.adt.action.user.ListUser"> ,O $F`0>9A
<param F0]= z-
h.=YAcR0D
name="page.everyPage">10</param> Q
>)?_O(
<result Hm%[d;Z7
0nG&
LL5
name="success">/user/user_list.jsp</result> ?RrJYj1
</action> N f1) 5
5|Vb)QBv%
</package> "fS9Nx3
<&b ~(f
</xwork> ()3+!};
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bAt!9uFn
D)4p8-=t
R#
mZYg
Ff%m.A8d,4
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 li,kW`j+t
I\`:(V
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 L.ndLd
oKzV!~{0M;
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 tgc&DT;E
DlfXzKn;
;MNEe%
TJ
3J%jD
AY,6Ddw
我写的一个用于分页的类,用了泛型了,hoho &!KJrQ
8I NVn'G
java代码: C'*1w
z&cfFx#h)
7A3e-51>
package com.intokr.util; B=|yjA'Fg
F#Z]Xq0r
import java.util.List; /xj'Pq((}p
%+xh
/** &hjrJ/'^
* 用于分页的类<br> L$lo5
* 可以用于传递查询的结果也可以用于传送查询的参数<br> Ya304Pjd
* bZ )3{
* @version 0.01 3l5q?" $
* @author cheng bZERh:%o
*/ _S@s
public class Paginator<E> { @fbvu_-].
privateint count = 0; // 总记录数 ?8YHz
privateint p = 1; // 页编号 )1lYfJ
privateint num = 20; // 每页的记录数 ;(VJZ_
privateList<E> results = null; // 结果 ''v_8sv
BU]9eF!>h
/** 'Kp|\Tr
* 结果总数 )k0bP1oGS
*/ $o{f)'.>n
publicint getCount(){ AO>K
6{
return count; dKZffDTZ
} ikyvst>O
sN^R Z0!>
publicvoid setCount(int count){ <bIAq8
this.count = count; z}u
} *Fp )/Ih
%w'@:~0
/** /of,4aaK7
* 本结果所在的页码,从1开始 evu @uq
* y4P mL
* @return Returns the pageNo. PNg, bcl
*/ .CwMxuW
publicint getP(){ ^J@Y?CQl\
return p; -L1{0{Z
} 4+ yd/^S
%|l*=v
/** $;$_N43
* if(p<=0) p=1 _g$6vx&
* nyTfTn
* @param p +4B>gS[ F
*/ 83)2c a
publicvoid setP(int p){ l,,5OZw
if(p <= 0) %J2u+K
p = 1; Y7!,s-v4W
this.p = p; xjv?Z"X
} 611:eLyy&l
#{i\t E
/** d}ue/hdw
* 每页记录数量 jJ|O]v$N
*/ L[##w?Xf.
publicint getNum(){ '.d el7s
return num; GZ*cV3Y`&
} NWv1g{M
*jf
(TIU
/** #Z (B4YO
* if(num<1) num=1 DkQy.
*/ +<8r?d2
publicvoid setNum(int num){ Ko2{[%
if(num < 1) %3'80u6BCJ
num = 1; uK3,V0 yz
this.num = num;
Hco[p+
} G#3 O^,m
b@z/6y!
/** v7xc01x
* 获得总页数 }3=]1jH6
*/ %k5^n0|*
publicint getPageNum(){ d,+d8X
return(count - 1) / num + 1; ] 6M- s
} !W .ooy5(
A;q}SO%b
/** T+N%KRl
* 获得本页的开始编号,为 (p-1)*num+1 6\/C]![%
*/ v#nYH?+~mJ
publicint getStart(){ $(.[b][S
return(p - 1) * num + 1; _z{:Q
} b":cj:mxL
'SvYZ0ot
/** 1+.(N:) +
* @return Returns the results. K7U`
*/ =<n+AqJ%
publicList<E> getResults(){ :a[L-lr`e
return results; GC~Tf rf=r
} '-S^z"ZrI
!1w=_
public void setResults(List<E> results){ SA)}---"
this.results = results; Et4gRS)\
} 50uNgLs
Ef:.)!;jy
public String toString(){ ]k
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j
StringBuilder buff = new StringBuilder >z.o?F
(7;}F~?h
(); `SZ^~O
buff.append("{"); =Y?M#3P.I
buff.append("count:").append(count); ^ejU=0+cN
buff.append(",p:").append(p); XGbtmmQG
buff.append(",nump:").append(num); ^<.mUaP
buff.append(",results:").append q}U^H
CAX|[
(results); RxjC sjg
buff.append("}"); S
XIo
return buff.toString(); (kK6=Mrf
} #Bj.#5
#t>w)`bA-
} =*~]lz__M
wm=!tx\`k
4
B"tz!