Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 hgO?+x
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 lR@& Z6lw
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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 K/|
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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 tpo>1|
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分页支持类: l.oBcg[
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java代码: 6m[9b*s7
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package com.javaeye.common.util; =dGKF`tR
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import java.util.List; El
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publicclass PaginationSupport { azX`oU,l
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publicfinalstaticint PAGESIZE = 30; 0T))>.iu#
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privateint pageSize = PAGESIZE; lFfXWNb
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privateList items; s.:r;%a
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privateint totalCount; #
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privateint[] indexes = newint[0]; _{Y$o'*#I
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privateint startIndex = 0; yM ,VrUh
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public PaginationSupport(List items, int ? )_7U
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totalCount){ t`u!]DHv
setPageSize(PAGESIZE); 7'OPjtM
setTotalCount(totalCount); j=ihbR^]Tl
setItems(items); Q2c*.Y
setStartIndex(0); N9]xJgTze
} Ttv'k*$cP
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public PaginationSupport(List items, int >^3zU
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totalCount, int startIndex){ VAKy^nR5j
setPageSize(PAGESIZE); xl2g0?
setTotalCount(totalCount); LgHJo-+>
setItems(items); F=}Z51|:~
setStartIndex(startIndex); "HC)/)Mv@
} c7qwNs*f
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public PaginationSupport(List items, int !8$RBD %
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totalCount, int pageSize, int startIndex){ JJ5C}`(
setPageSize(pageSize); frqJN
setTotalCount(totalCount); z*LiweR-
setItems(items); hZN<Yd8:
setStartIndex(startIndex); ~G`J
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} C3S`}o.
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publicList getItems(){ $bGD%9
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return items; I=[cZ;t
} &&PgOFD
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publicvoid setItems(List items){ XDYosC:
this.items = items; a)9rs\Is{
} 16$y`~c-z
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publicint getPageSize(){ r7I
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return pageSize; m:{tgcE
} 9+Nw/eszO
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publicvoid setPageSize(int pageSize){ %MJ;Q?KB
this.pageSize = pageSize; 8#59iQl
} d+}k g
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publicint getTotalCount(){ 3k'.(P|F
return totalCount; A1A3~9HuK
} 5f{|"LG&
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publicvoid setTotalCount(int totalCount){ &iSD/W
if(totalCount > 0){ Nn#u%xvJt
this.totalCount = totalCount; 9#rt:&xo0
int count = totalCount / Z@J.1SaB
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pageSize; &qRJceT(
if(totalCount % pageSize > 0) ~m`!;rE
count++; V8"Wpl9Cz
indexes = newint[count]; 0YS?=oi
for(int i = 0; i < count; i++){ QIV%6q+*R
indexes = pageSize * h^M^7S
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i; K{b-TT
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} @G GccF
}else{ 2c:f<>r0y
this.totalCount = 0; &1Fply7(Ay
} \9/1L?@
} /cY^]VLe
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publicint[] getIndexes(){ qY# d+F,t
return indexes; nb+m.X
} @vs@>CYdz
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publicvoid setIndexes(int[] indexes){ J70D+
this.indexes = indexes; >o[|"oLO
} L2|aHI1'l
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publicint getStartIndex(){ }*kJ-q&0
return startIndex; LfX0Z=<
} .ECHx Dp
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publicvoid setStartIndex(int startIndex){ @]'SeiNp
if(totalCount <= 0) g%\L&}Jd
this.startIndex = 0; qm(1:iK,0
elseif(startIndex >= totalCount) 1^{`lK~2
this.startIndex = indexes ._<ii 2K'
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[indexes.length - 1]; =n0*{~r
elseif(startIndex < 0) fk3kbdI
this.startIndex = 0; 8/Rm!.8+~
else{ c8DZJSO
this.startIndex = indexes `ROEV~
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[startIndex / pageSize]; $a.u05
} _CdROo6I
} U9ZbVjqv@
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publicint getNextIndex(){ b!a
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int nextIndex = getStartIndex() + ^M
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pageSize; A=`*r*
if(nextIndex >= totalCount) /iC_!n u
return getStartIndex(); kuS/S\Z5K
else GGE[{Gb9
return nextIndex; _ #'9kx|)
} 8H
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publicint getPreviousIndex(){ >q(6,Mmb
int previousIndex = getStartIndex() - N@1p]\
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pageSize; "#S>I8d
if(previousIndex < 0) g6euXI
return0; v0 ];W|
else oI@9}*
return previousIndex; 5"=:#zN
} frH)_ YJ%
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} DuNcX$%%
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抽象业务类 }gCHQ;U7`
java代码: POGw`:)A
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/** )zJ=PF
* Created on 2005-7-12 y8?t-Pp]1
*/ J}@GKNm
package com.javaeye.common.business; %h+uD^^$
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import java.io.Serializable; g42T#p8^
import java.util.List; IJPgFZ7
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import org.hibernate.Criteria; 9}
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import org.hibernate.HibernateException; (hf zM+2
import org.hibernate.Session; AMTslo
import org.hibernate.criterion.DetachedCriteria; Y6VQ:glDT-
import org.hibernate.criterion.Projections; J
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import C EqZ:c
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org.springframework.orm.hibernate3.HibernateCallback; afm_ Rrg[
import 'h}7YP, w
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org.springframework.orm.hibernate3.support.HibernateDaoS E5{n?e
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upport; x!?Z*v@I
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import com.javaeye.common.util.PaginationSupport; :]c=pH
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public abstract class AbstractManager extends ]kS7n@8
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HibernateDaoSupport { `d*b]2
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privateboolean cacheQueries = false; a:u}d7T3e
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privateString queryCacheRegion; h7?.2Q&S
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publicvoid setCacheQueries(boolean ;3UvkN
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cacheQueries){ E@pFTvo
this.cacheQueries = cacheQueries; 1nB@zBQu-
} sqG`"O4W
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publicvoid setQueryCacheRegion(String q\H7&w
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queryCacheRegion){ d_T<5Hin
this.queryCacheRegion = e?<D F.Md+
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queryCacheRegion; }17bV, t
} m!Af LSlwm
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publicvoid save(finalObject entity){ b-nY xd
getHibernateTemplate().save(entity); mV zu~xym
} *<kD"m
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publicvoid persist(finalObject entity){ !!+Da>
getHibernateTemplate().save(entity); t/ eo]
} P6we(I`"2
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publicvoid update(finalObject entity){ \7
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getHibernateTemplate().update(entity); ~:Ixmqi}R
} q^6N+ ^}QN
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publicvoid delete(finalObject entity){ \`gEu{
getHibernateTemplate().delete(entity); s3< F
} sVoR?peQ
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publicObject load(finalClass entity, Omb.53+
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finalSerializable id){ ;]@exp5
return getHibernateTemplate().load \G3!TwC%
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(entity, id); 4:3_ER ]J
} GZ"/k<~0
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publicObject get(finalClass entity, *(nJX.7
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finalSerializable id){ i[_|%'p
return getHibernateTemplate().get o=mo/N4
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(entity, id); D1ZC&B_}-
} /.v_N%*-v
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publicList findAll(finalClass entity){ uk6g s)qxC
return getHibernateTemplate().find("from 0BFz7
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" + entity.getName()); ^S=cNSpC
} ~oFh>9u
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publicList findByNamedQuery(finalString +"Ub/[J{G1
+ !xu{2 !
namedQuery){ V4\560
return getHibernateTemplate sDAK\#z
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().findByNamedQuery(namedQuery); 2_N/wR#=&
} en%B>]QI
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publicList findByNamedQuery(finalString query, ?\M)WDO
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finalObject parameter){ SS0_P
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return getHibernateTemplate J% AG`
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().findByNamedQuery(query, parameter); QQq/5r4O`q
} E[*0Bo]
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publicList findByNamedQuery(finalString query, Z>h{`
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finalObject[] parameters){ S;h&5.p
return getHibernateTemplate 952V@.Zp
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().findByNamedQuery(query, parameters); oX*b<d{\N
} Y2D>tpqNw
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publicList find(finalString query){ sL8>GtVo
return getHibernateTemplate().find GVZTDrC
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(query); g41<8^(
} #@q1Ko!NZ
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publicList find(finalString query, finalObject 5f{wJb2
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parameter){ ~.H~XKw
return getHibernateTemplate().find *F..ZS'$[
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(query, parameter); <d S5|||
} yeNvQG
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public PaginationSupport findPageByCriteria j^{b^!4~}
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(final DetachedCriteria detachedCriteria){ FXxN>\76.
return findPageByCriteria UtPwWB_YV
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); S<9gyW
} hWm0$v1p
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public PaginationSupport findPageByCriteria :^5>wDu{
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(final DetachedCriteria detachedCriteria, finalint d96fjj~
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startIndex){ YLE/w @*
return findPageByCriteria IOS^|2:,
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(detachedCriteria, PaginationSupport.PAGESIZE, A`g.[7
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startIndex); <oQ6 Z X
} }\EL;sT
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public PaginationSupport findPageByCriteria py=i!vb&Z%
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(final DetachedCriteria detachedCriteria, finalint Zq^^|[)bA
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pageSize, >ks3WMm
finalint startIndex){ :|Upx4]Ec
return(PaginationSupport) 4':MI|/my_
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getHibernateTemplate().execute(new HibernateCallback(){ :Fc8S9
publicObject doInHibernate -&$%|cyThQ
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(Session session)throws HibernateException { 16L"^EYq
Criteria criteria = |MVV +.X
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detachedCriteria.getExecutableCriteria(session); zWJKYF qK
int totalCount = Ls(&HOK[p
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((Integer) criteria.setProjection(Projections.rowCount mcCB7<.
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()).uniqueResult()).intValue(); yX`J7O{=
criteria.setProjection UYH|?Jw!N
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(null); f^~2^p
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List items = M.X}K7Z_/
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criteria.setFirstResult(startIndex).setMaxResults p?}&)Un
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(pageSize).list(); } mgVC
PaginationSupport ps = i:;$oT
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new PaginationSupport(items, totalCount, pageSize, ?~{rf:Y
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startIndex); 7bHE!#L`0
return ps; xiEcEz'lk
} y)IGTW o
}, true); &&ja|o-
} xJ$Rs/9C
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public List findAllByCriteria(final 7(H?k
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DetachedCriteria detachedCriteria){ DZ,<Jmg&e*
return(List) getHibernateTemplate \
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().execute(new HibernateCallback(){ 87R%ke
publicObject doInHibernate cl?<
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(Session session)throws HibernateException { W31LNysH!;
Criteria criteria = B$@1QG
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detachedCriteria.getExecutableCriteria(session); /nwxuy
return criteria.list(); uwmoM>I W^
} D\@e{.$MZ|
}, true); $#D
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}
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public int getCountByCriteria(final H^ESAs6
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DetachedCriteria detachedCriteria){ Y!bpOa&
Integer count = (Integer) 3/SfUfWo
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getHibernateTemplate().execute(new HibernateCallback(){ C3]\$
publicObject doInHibernate K<D`(voL
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(Session session)throws HibernateException { 7ZL,p:f
Criteria criteria = !Jk(&.
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detachedCriteria.getExecutableCriteria(session); nZ" {y
return y?[5jL|Ue
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criteria.setProjection(Projections.rowCount ~GAlNIv]
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()).uniqueResult(); b0!*mrF]6
} 3csm`JVK
}, true); M-{b
return count.intValue(); vd2uD2%con
} b5lk0 jA
} &8pCHGmV)
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用户在web层构造查询条件detachedCriteria,和可选的 AN|jFSQ'
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 Z&AHM &,yj
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PaginationSupport的实例ps。 6-)7:9y
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ps.getItems()得到已分页好的结果集 LsuAOB 8
ps.getIndexes()得到分页索引的数组 !l sy&6
ps.getTotalCount()得到总结果数 Ukk-(gjX
ps.getStartIndex()当前分页索引 )$2%&9b
ps.getNextIndex()下一页索引 ]#vvlM>/
ps.getPreviousIndex()上一页索引 :DS2zA
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 X
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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 jKY Aid{-
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一下代码重构了。 8:3oH!n
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我把原本我的做法也提供出来供大家讨论吧: @lb=-oR!~
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首先,为了实现分页查询,我封装了一个Page类: >S?C {_g
java代码: PCV58n3
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/*Created on 2005-4-14*/ pIU#c&%<9
package org.flyware.util.page; Zztt)/6*
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/** Thht_3_C,f
* @author Joa orcZyYU
* /-G qG)PX
*/ !`O_VV`/@
publicclass Page { G#9o?
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/** imply if the page has previous page */ a<a&63
privateboolean hasPrePage; E.7AbHph0
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/** imply if the page has next page */ Mipm&5R
privateboolean hasNextPage; }`+^|1
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/** the number of every page */ $ ufSNx(F
privateint everyPage; 9H
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dw{#||
/** the total page number */ SoXX}<~E4
privateint totalPage; n)1
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/** the number of current page */ cpr{b8Xb8&
privateint currentPage; tF;& x
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/** the begin index of the records by the current 110>p
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query */ .yFg$|y G
privateint beginIndex; E,ZB;
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/** The default constructor */ (>+k 3
public Page(){ 5tgILxSK
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} 4$q)e<-
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/** construct the page by everyPage }]n>A
* @param everyPage -Fok%iQ'5
* */ ,
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public Page(int everyPage){ BRSgB-Rr7
this.everyPage = everyPage; XEgx#F ;F
} Im' :sJ31
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/** The whole constructor */ k_En_\c?p2
public Page(boolean hasPrePage, boolean hasNextPage, >H=Q$gI
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int everyPage, int totalPage, xi1N?
pP
int currentPage, int beginIndex){ -!bLMLIg
this.hasPrePage = hasPrePage; b*6c.o
this.hasNextPage = hasNextPage; 0Z1H6qn
this.everyPage = everyPage; "M5ro$qZ}
this.totalPage = totalPage; U~){$kpI#
this.currentPage = currentPage; l6}b{e
this.beginIndex = beginIndex; 6b+ WlIb
} Vgru, '
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/** m|e*Jc
* @return G\,A> mT/P
* Returns the beginIndex. uz#eO|z@o
*/ ;*37ta
publicint getBeginIndex(){ Fy(nu-W
return beginIndex;
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} tmY-m,U
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/** hk lO:,`
* @param beginIndex dPyBY]`
* The beginIndex to set. z7.C\l
*/ v{rK_jq
publicvoid setBeginIndex(int beginIndex){ 13>3R+o
this.beginIndex = beginIndex; )o'U0rAx|a
} &"H<+>`
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/** @L>NN>?SGQ
* @return >gOI]*!5
* Returns the currentPage. !+|N<`
*/ C$..w80/1
publicint getCurrentPage(){ (61twutC
return currentPage; 9^
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} ~a8G 5M
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/** YL&b9e4
* @param currentPage 1UA~J|&gi^
* The currentPage to set. /nD0hb
*/ 8a$jO+UvN
publicvoid setCurrentPage(int currentPage){ {GH`V}Ob
this.currentPage = currentPage; 7L~ zI>2
} h7W%}6Cqkw
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/** =Q=&Ucf_
* @return fFTvf0j
* Returns the everyPage. B,m$ur#$
*/ }2!5#/^~
publicint getEveryPage(){ 3EW f|6RI
return everyPage; UN
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} 2Fp]S
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/** {+UNjKQC
* @param everyPage 4pTuP /
* The everyPage to set. _]~ht H
*/ NV:XPw/
publicvoid setEveryPage(int everyPage){ eS@!\Hx
this.everyPage = everyPage; '*LN)E>d
} hZ\W ?r
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/** 'B<qG<>
* @return m5;[,He
* Returns the hasNextPage. {@K2WB
*/ xMfv&q=k@
publicboolean getHasNextPage(){ O]%m{afM
return hasNextPage; a_iQlsU
} xP/1@6]_Je
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/** ^qN1~v=hS
* @param hasNextPage []N$;~R7
* The hasNextPage to set. /HJ(Wt
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*/ RnBmy^l"
publicvoid setHasNextPage(boolean hasNextPage){ Sp$x%p0
this.hasNextPage = hasNextPage; /%q9hI
} Nj@?}`C 4
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/** r dG2| Tp
* @return <iprPk
* Returns the hasPrePage. D15u1A
*/ _d=&9d#=\
publicboolean getHasPrePage(){ ://#
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return hasPrePage; ]E8<;t)#
} 6RT0\^X*:
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/** I&NpN~AU
* @param hasPrePage !%\To(r[
* The hasPrePage to set. rs<&x(=Hv
*/ H{A| ~V)
publicvoid setHasPrePage(boolean hasPrePage){ Ho._&az9cT
this.hasPrePage = hasPrePage; jnKM6%z
} ch8w'
wrb& ta
/** (yTz^o$t|
* @return Returns the totalPage. c+i`Zd.m<
* cxJK>%84
*/ I/b8
publicint getTotalPage(){ $\@ V4
return totalPage; ,t&-`U]AX
} ~md|k
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/** .rB;zA;4S)
* @param totalPage n
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* The totalPage to set. I~]mX;
*/ MJ/%$
publicvoid setTotalPage(int totalPage){ _NqT8C4C
this.totalPage = totalPage; *_K-T#
} GuY5 %wr
<w2NJ~M^
} 6.7Kp
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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 w~KBk)!*
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个PageUtil,负责对Page对象进行构造: -GWzMBS S
java代码: _,0!ZP-
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/*Created on 2005-4-14*/ tP(bRQ>
package org.flyware.util.page; ee0>B86tE
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import org.apache.commons.logging.Log; R}6la.mQ
import org.apache.commons.logging.LogFactory; Tocdh.H|
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/** 1@z@
* @author Joa ow$l!8
* ;AB ,:*
*/ rJQ|Oi&1i
publicclass PageUtil { K/d&c]
^W[`##,{Od
privatestaticfinal Log logger = LogFactory.getLog !=:MG#p
<H@!Xw;
(PageUtil.class); E1ob+h:`d
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/** g+r{>x
* Use the origin page to create a new page BCZnF
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* @param page PZg]zz=V4
* @param totalRecords uvv-lAbjw
* @return [%,=0P}
*/ PyxN _agf
publicstatic Page createPage(Page page, int
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totalRecords){ m:Cx~
return createPage(page.getEveryPage(),
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"v(]"L
page.getCurrentPage(), totalRecords); `/ReJj&~
} \lIHC{V\
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/** JU \J
* the basic page utils not including exception |=}~>!!
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handler I"<.
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* @param everyPage ]sP9!hup
* @param currentPage 5N+(Gv[`"
* @param totalRecords oqHm:u^2
* @return page by<@Zwtf
*/ .LcE^y[V
publicstatic Page createPage(int everyPage, int '<D}5u72
78~V/L;@S2
currentPage, int totalRecords){ 'p+QFT>Ca
everyPage = getEveryPage(everyPage); ;p!hd}C
currentPage = getCurrentPage(currentPage); :BxYaAVt^
int beginIndex = getBeginIndex(everyPage, ZLX`[
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currentPage); WzbN=&
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int totalPage = getTotalPage(everyPage, VD`2lGdF
7#.PMyK9
totalRecords); kGiw?~t=%
boolean hasNextPage = hasNextPage(currentPage, !Ocg
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totalPage); a(T4WDl^
boolean hasPrePage = hasPrePage(currentPage); }M@Jrq+7
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returnnew Page(hasPrePage, hasNextPage, }4]x"DfIg
everyPage, totalPage, 'wV26Dm
currentPage, V="f)'S$
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beginIndex); \#7%%>p=O'
} Riuv@i^6K
6;XpLivP7
privatestaticint getEveryPage(int everyPage){ MJpTr5Vs
return everyPage == 0 ? 10 : everyPage; Z@O
e}\.$
} 6v)eM=
^F9zS`Yz2
privatestaticint getCurrentPage(int currentPage){ R*eM 1
return currentPage == 0 ? 1 : currentPage; 2#}IGZ`Yp/
} qA/3uA!z
b+apN ph
privatestaticint getBeginIndex(int everyPage, int `^k<.O
TiEJyd`P
currentPage){ jAHn`Bxz
return(currentPage - 1) * everyPage; &-Er n/[
} eG>Fn6G<g
IVODR
privatestaticint getTotalPage(int everyPage, int HTpd~W/\
48rYs}
totalRecords){ ]=<@G.[=
int totalPage = 0; &`2*6
)qa
[;8fL
if(totalRecords % everyPage == 0) lS*.?4zX
totalPage = totalRecords / everyPage; D ,^
U%<`
else \ jdO,-(
totalPage = totalRecords / everyPage + 1 ; %t.IxMY
6.=1k
return totalPage; vGp@YABM
} tzJtd
=H?5fT^
privatestaticboolean hasPrePage(int currentPage){ oD1=}
return currentPage == 1 ? false : true; d}J#wT
} |q)Q<%VS'
A~SSu.L@
privatestaticboolean hasNextPage(int currentPage, Mn;CG'FA
c4W"CD;D
int totalPage){ vAxtNRS
return currentPage == totalPage || totalPage == aKr4E3`
n :kxG
0 ? false : true; ~36XJ
} uoc-qmm
e}w!]
fltcdA
} u)>*U'bM
I@v.Hqg+7
vB4qJ{f
5X|aa>/
|<icx8hbr
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。 vtjG&0GSK
D)6|| z}
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 RlIqH;n
oC>~r1.j
做法如下: o:ob1G[p%
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ;%9ZL[-
[/]3:|
的信息,和一个结果集List: !Xce iQu
java代码: J1MnkxJmpQ
#R|4(HlL
b~echOj
/*Created on 2005-6-13*/ +Q&@2 oY"
package com.adt.bo; u:?RdB}B_@
]xs\,}I%
import java.util.List; NKYyMHv6
zaPR>:r0
import org.flyware.util.page.Page; CcETS}Q0C
Pfy;/}u^c
/** ^r$5];n
* @author Joa $yJfAR
*/ ga%77t|jm3
publicclass Result { Q"uu&JC
aW5~z^I
private Page page; i?9Lf
Pw1H)<X
private List content; kp"cHJNx
-7Wmq[L/
/** AP@d2{"m}
* The default constructor #}?$mxME*
*/ F@3,>~[%I
public Result(){ oaE3Aa
super(); ]P^ +~
} 6Wp:W1E{`
=wc[r?7
/** Hq8.O/Y"=
* The constructor using fields G9Ezm*I;:
* ST.W{:X
* @param page qxh\umm+2
* @param content b2H6}s"=w
*/ 9!h+LGs(,
public Result(Page page, List content){ ~.tu#Y?
this.page = page; K*[wr@)u
this.content = content; ['j,S<Bu~
} oQO3:2a
X_2I4Jz]6
/** ['<rfK
* @return Returns the content. 7#QH4$@1P
*/ nK$m:=
publicList getContent(){ e{/\znBS%
return content; Joj8'
} *z~Y *Q0
:=@[FXD4
/** I&0yUhn
* @return Returns the page. |n/id(R+
*/ 1??RX}8[L+
public Page getPage(){ !b=$FOC>
return page; ^&%?Q_]
} iV=#'yY
L3\{{QOA
/** n\4+xZr
* @param content -TWo-iu^
* The content to set. .>e~J+oL
*/ @ck2j3J/
public void setContent(List content){ g(Nf.hko
this.content = content; ^4:= b
} |v&&%>A2
)Ec;kr b+
/** s+11) ~
* @param page }, H,ky
* The page to set. ]]4E)j8
*/ ^C{a'
publicvoid setPage(Page page){ {iv=KF_S_
this.page = page; {3>^nMv@e
}
LWE
!+(n
} n:+MNr
'7^_$M3$\
:|g{gi
Z8W<RiR
)_uK(UNZ5
2. 编写业务逻辑接口,并实现它(UserManager, ~jaGf
y;H
3g#
UserManagerImpl) \<%a`IA!*
java代码: [+GG Wo
f &|SGD*
5P4>xv[
/*Created on 2005-7-15*/ CT : ac64
package com.adt.service; |bh:x{h
-e ya$C
import net.sf.hibernate.HibernateException; 8V nZ@*
UJI1n?~
import org.flyware.util.page.Page; RK0IkRXQd
6lPGop]js]
import com.adt.bo.Result; @`yfft
C-7.Sa
/** `i-&Z`
* @author Joa ]iPdAwc.1
*/ j:#[voo7
publicinterface UserManager { uIu0"pv`x
@`{UiTNX`
public Result listUser(Page page)throws -3Ffk:
wJ}8y4O!N
HibernateException; @S}'_g
S=Zjdbd
} uf6{M_jXZ
[T|~Kh%#
.Qaqkb-Ty
$8Zw<aEJ
Qk6FK]buV
java代码:
`@p*1
YG% Zw
0y(d|;':
/*Created on 2005-7-15*/ O/-xkzR*
package com.adt.service.impl; `]Xbw^Y'x
q7;)&_'
import java.util.List; ,70|I{,Km
.R1)i-^
import net.sf.hibernate.HibernateException; uZNR]+Yu@
6^p6v
import org.flyware.util.page.Page; +um;
eL7
import org.flyware.util.page.PageUtil; -Fb/GZt|
y ^YrGz.
import com.adt.bo.Result; S7V;sR"V2
import com.adt.dao.UserDAO; tY7u\Y;^
import com.adt.exception.ObjectNotFoundException; 49CMRO,T
import com.adt.service.UserManager; sx9N8T3n
jN[Z mJz'
/** nQ mkDPjU
* @author Joa *I~F7Z]|
*/ e='3gzz
publicclass UserManagerImpl implements UserManager { a*=e 3nS
,}NG@JID
private UserDAO userDAO; k;%}%"EVZ
q+N}AKawB
/** &B)
F_E I
* @param userDAO The userDAO to set. Jyd%!v
*/ \"5 \hX~dS
publicvoid setUserDAO(UserDAO userDAO){ Yz,*Q<t
this.userDAO = userDAO; Ys\l[$_`*
} } nQHP4'
%K zURv
/* (non-Javadoc) 5K8\hoW{
* @see com.adt.service.UserManager#listUser Si;e_a
zdY`c
(org.flyware.util.page.Page) +q3W t|
*/ ).-FuL4Y
public Result listUser(Page page)throws fx*Swv%r
Z*JZUbo-Q
HibernateException, ObjectNotFoundException { C?zC|0
int totalRecords = userDAO.getUserCount(); Dj[D|%9a
if(totalRecords == 0) ': HV9]k
throw new ObjectNotFoundException mCg 5-E~;
'0[l'Dt'
("userNotExist"); 7n#0eska,
page = PageUtil.createPage(page, totalRecords); tJ 6:$dh
List users = userDAO.getUserByPage(page); 7UMsKE-
returnnew Result(page, users); p.zU9rID
} &fW;;>
-QRKDp
} &We'omq
J?%Z7&/M>
P afmHXx
'Y[\[]3[8
-2f0CAh~
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 m0 `wmM
%F03cI,
询,接下来编写UserDAO的代码: py)V7*CgH
3. UserDAO 和 UserDAOImpl: pxP7yJL`
java代码: ] $5r h8
@%RDw*L(
X2s=~)`#c
/*Created on 2005-7-15*/ KBXdr5 2"
package com.adt.dao;
!Qn:PSk
Xc'yz 2B
import java.util.List; SMnbI.0
O9!<L.X,%
import org.flyware.util.page.Page; ]Dx5t&
z.7 UfLV9
import net.sf.hibernate.HibernateException; _c`Gxt%
P4s:wuJ^
/** 64[j:t=N
* @author Joa 7pkc*@t
*/ n`CmbM@@
publicinterface UserDAO extends BaseDAO { D`Fl*Wc4H
sjztT<{Q^-
publicList getUserByName(String name)throws t@b';Cuv
#*?a"
HibernateException;
~B/|#o2
)5bhyzSZI
publicint getUserCount()throws HibernateException; R\6#J0&Y-
.0Cpqn,[
publicList getUserByPage(Page page)throws <TDgv%eg0
^m?h .
HibernateException; -Ndd6O[ a5
{R&F_51)V
} e-x{7
,OG sx
!G,Ru~j5:
nAg|m,gA
ZcIwyh(`
java代码: W)o-aX!P
OfIml.
%$S.4#G2
/*Created on 2005-7-15*/ i |cSO2O+
package com.adt.dao.impl; XYf;72*
?f:FmgQk
import java.util.List; _^Rf*G !
vfmKY iLp
import org.flyware.util.page.Page; E+csK*A7
. [*6W.X
import net.sf.hibernate.HibernateException; i
yMIP~N,$
import net.sf.hibernate.Query; ."cC^og
c!E+&5|n
import com.adt.dao.UserDAO; KK/~W
_epi[zf@
/** -SZ^;t
* @author Joa q^k6.5*"
*/ ;
*r5 d+]
public class UserDAOImpl extends BaseDAOHibernateImpl !=Cd1
$<
WY #pzBA
implements UserDAO { iwrS>Sm
L/#^&*'B
/* (non-Javadoc) A03,X;S+
* @see com.adt.dao.UserDAO#getUserByName n`;=^^ B
HSq&'V
(java.lang.String) =[3I#s?V
*/ 8+Oyhd*|
publicList getUserByName(String name)throws r>A,7{
KGFmC[
HibernateException { >4b-NS/}0
String querySentence = "FROM user in class @/yef3
7l%O:M(\
com.adt.po.User WHERE user.name=:name"; (?;Fnq
Query query = getSession().createQuery `+{|k)2B
u0Irf"Ab
(querySentence); ^0c:ro
query.setParameter("name", name); _L<IxOZh+
return query.list(); 6xvy hg#B
} Em %"]B
;y
Wfb|!
/* (non-Javadoc) ){ArZjG>
* @see com.adt.dao.UserDAO#getUserCount() WR%x4\,d#
*/ 0Evq</
publicint getUserCount()throws HibernateException { fMP$o3;
int count = 0; ="JLUq*]s
String querySentence = "SELECT count(*) FROM !*'uPw:l2
hZU@35~BN
user in class com.adt.po.User"; =T|Z[/fto
Query query = getSession().createQuery Tz:mj
rq:R6e
(querySentence); ]|@RWzA
count = ((Integer)query.iterate().next Xq` '^)
cEhwv0f!qS
()).intValue(); uR"(0_
return count; UW88JA0
} $
nx&(V
IhhB^E|
/* (non-Javadoc) IJhJfr0)Oo
* @see com.adt.dao.UserDAO#getUserByPage E}00y%@*J
cL?FloPc*
(org.flyware.util.page.Page) M\ B A+
*/ oEGe y8?
publicList getUserByPage(Page page)throws gR
)xw)!
~kj1L@gy
HibernateException { W4Tuc:X5
String querySentence = "FROM user in class tn>$5}^;
4U(W~O
com.adt.po.User"; UMuRB>ey
Query query = getSession().createQuery 0L9z[2sj
hW P$U
(querySentence); PVC\&YF
query.setFirstResult(page.getBeginIndex()) QI0d:7!W1
.setMaxResults(page.getEveryPage()); )`, Bt
return query.list(); h%|Jkx!v-t
} tg_v\n
R/VrBiw
} TyI"fP
}`FC'!(
w)2X0ev"
Yg3Vj=
7j8nDX<
至此,一个完整的分页程序完成。前台的只需要调用 }\!&3^I
_l<e>zj
userManager.listUser(page)即可得到一个Page对象和结果集对象 8!(4;fN$j.
9TuE.
的综合体,而传入的参数page对象则可以由前台传入,如果用 G|*^W;(Z
RP?UKOc
webwork,甚至可以直接在配置文件中指定。 S:"R/EE(
p(-f $Q(
下面给出一个webwork调用示例: QVA)&k'T,
java代码: eo.y,U h
38ChS.(
%9cu(yc*}
/*Created on 2005-6-17*/ _ +q.R
package com.adt.action.user; kC"lO'
z%Pbs[*C
import java.util.List; A%qlB[!:
Dl_y[9
import org.apache.commons.logging.Log; Y]!8Ymuww@
import org.apache.commons.logging.LogFactory; -!zyit5B
import org.flyware.util.page.Page; ZJlmHlAX
} Wx#"6
import com.adt.bo.Result; !#wd~: H
import com.adt.service.UserService; x%Ivd
import com.opensymphony.xwork.Action; yqi=9NB
~<!b}Hv
/** 5Arx"=c
* @author Joa \3a(8Em
*/ 0.7*2s-
publicclass ListUser implementsAction{ *.nC'$-2r
c((^l&
privatestaticfinal Log logger = LogFactory.getLog nG
hFY Ql
" lar~
(ListUser.class); 1#9qP~#]'{
kqxX!
private UserService userService; a"ZBSg(
-L<''2t
private Page page; NZ`Mq
XMzL\Edo
privateList users; Z\Qa6f!
%P05k
/* 6P@3UQ)}s
* (non-Javadoc) 8#b>4Dx
* G$FNofQx
* @see com.opensymphony.xwork.Action#execute() QbA+\
*/ O{u^&V]
publicString execute()throwsException{ IWbW=0IsS
Result result = userService.listUser(page); |a/1mUxQ&
page = result.getPage(); ug47JW
users = result.getContent(); "9mJ$us
return SUCCESS; gwHNz5 a*V
} `hJSo?G>
WPLM*]6
/** >5G2!Ns'
* @return Returns the page. $#E?`At{I
*/ ?fF{M%i-%
public Page getPage(){ 0tV" X
return page; doM}vh)6
} `uK_}Vy_
~Mu=,OT
/** Pt<lHfd
* @return Returns the users. $7
1(g$6#
*/ ^D`ARH
publicList getUsers(){ H3<
`
return users; DY]\@<ez
} Gc6`]7 s
eF)vx{s
/** V0y Q
* @param page t<'-?B2g
* The page to set. ^@V$'Bk
*/ &d/v/Y
publicvoid setPage(Page page){ _c|aRRW
this.page = page; jn[%@zD }
} O{WJi;l
tu(k"'aJ
/** 4'L%Wz[6
* @param users J`F][ A
* The users to set. O%:EPdoU
*/ 1~X~"M
publicvoid setUsers(List users){ )<W6cDx'H+
this.users = users; F=}-ngx8&
} nU]4)t_o\
LZC)vF5
/** F@=)jrO=$
* @param userService |/LCwq%
* The userService to set. V *2=S
*/ QvB]?D#h
publicvoid setUserService(UserService userService){ tTa" JXG
this.userService = userService; ,1>ABz
} X[pk9mha
} qSj$0Hq5XI
doJ\7c5uU
MN|8(f5Gs
-26GOS_8z
T/8*c0mU
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, GUUVE@Z
:m|%=@]`
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 7vBB <\
C/nzlp~
么只需要: QC+oSb!!?
java代码: <cTusC<
etbB;!6
~c8Z9[QW
<?xml version="1.0"?> Y>eypfK"
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork K]q9wR'q
_VIVZ2mU=
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ep]tio_
k:D;C3vJd
1.0.dtd"> q!l[^t|;
==d@0`
<xwork> z;x1p)(xt
Vj.5b0/(
<package name="user" extends="webwork- y~jKytq^@
4BSSJ@z
interceptors"> Y)%CxaO`
[[fhfV+H
<!-- The default interceptor stack name K<`"Sr
|Tz/9t
--> >icK]W
<default-interceptor-ref G~Oj}rn
v&:R{
name="myDefaultWebStack"/> ,~@0IKIA
Q
lqC
a%V
<action name="listUser" c"mRMDg%
^s'ozCk 0
class="com.adt.action.user.ListUser"> 0q%=Vs~@g
<param _J}vPm
ii%n:0+zm
name="page.everyPage">10</param> v5i?4?-Z
<result P<iS7Ys+
^:0NKq\
name="success">/user/user_list.jsp</result> x+h7OvW{
</action> H^s@qh)L
>j]*=&,7
</package> ]#hT!VOd
GnbXS>
</xwork> 'c#ZW|A
w}Q|*!?_
&HKrmFgX{
xe)< )y
wzAp`Zs2Dm
7S<Z&1(
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 ?3tR(H<
1a{~B#
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 38P_wf~\
p-U'5<n
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 Xg#g`m%(M
^=)? a;V
,wmPK;j
`m5cU*@D
dy u brIG
我写的一个用于分页的类,用了泛型了,hoho rn1FCJ<;H
?5m[Qc(<
java代码: '{EBK
A0*u(15%
]2Aqqy
package com.intokr.util; ;F@dN,Y
Kb%j;y
import java.util.List; YW"?Fy
1 sCF
-r
/** o?P(Fuf
* 用于分页的类<br> "42u0rH0J
* 可以用于传递查询的结果也可以用于传送查询的参数<br> d>F=|dakL
* Jrlc%,pZ
* @version 0.01 BY:
cSqAW
* @author cheng whP>'9t.w
*/ (E)/' sEb
public class Paginator<E> { Xmy(pV!PF
privateint count = 0; // 总记录数 cXcn}gKV
privateint p = 1; // 页编号 8}p 5MG
privateint num = 20; // 每页的记录数 yS/ovd
privateList<E> results = null; // 结果 T8YqCT"EA<
N i^pP@('
/** ?Gr<9e2Eo
* 结果总数 ->vfQwBFd
*/ 0-Xpq,0
publicint getCount(){ &Qghm o
return count; nLkC-+$tM
} iXC/?
EK4
U^ BB|
publicvoid setCount(int count){ xtU)3I=F%
this.count = count; :i*JlKHJd
} cd}TDd(H%
"/hs@4{u9
/** dQA J`9B
* 本结果所在的页码,从1开始 t]FFGnBZ
* +u_mT$|T
* @return Returns the pageNo. y)U8\
*/ O3*Vilx
publicint getP(){ -tx)7KV-
return p; qd3B>f
} DC*|tHl
h bj^!0m
/** {NE;z<,*:
* if(p<=0) p=1 /eR @&!D '
* LnZz=
* @param p ~;m~)D
*/ W5:S+
publicvoid setP(int p){ _?Jm.nT
if(p <= 0) =KT7ZSTV
p = 1; r3Z-mJ$:
this.p = p; :[(X!eP
} )2F:l0g
k`
(_~/#
/** c<JJuG
* 每页记录数量 ycw'>W3.*
*/ Re<X~j5]
publicint getNum(){ V6wYJ$]
return num; $K<jmEC@<
} 7"4|`y^#
iO#H_&L.p
/** jopC\Z
* if(num<1) num=1 xNxIqq<k
*/ %XG X(
publicvoid setNum(int num){ {yVi/*;f^
if(num < 1) D (qT$#
num = 1; -lSm:O@'
this.num = num; 9'//_ A,
} ZWf{!L,@Z
.(9IAAwKn
/**
e%'9oAz
* 获得总页数 cx_"{`+e
*/ WKxJ`r\
publicint getPageNum(){ Kt}dTpVFr
return(count - 1) / num + 1; pJ_Z[}d)c
} 4B]8Mp~\aL
#C%<g:F8
/** zCvR/
* 获得本页的开始编号,为 (p-1)*num+1 m/Yi;>I(
*/ 'zT/x`V
publicint getStart(){ GUat~[lUrj
return(p - 1) * num + 1; |Z 3POD"9
} 8agd{bxU
^@X
=v`C
/** N@)4H2_u \
* @return Returns the results. Hg(\EEe
*/ ]iLfe&f
publicList<E> getResults(){ Iobo5B
return results; @gX@mT"
} Bfw>2
5W<BEcV\
public void setResults(List<E> results){ D"1ciO8^I]
this.results = results; ]]%C\Ryy}
} 0TA/ExJ-LT
!2&h=;i~V
public String toString(){ ?wwY8e?S
StringBuilder buff = new StringBuilder zP=J5qOZ8
bk4%lYJ"
(); $8it&/JP,
buff.append("{"); f "Iv
buff.append("count:").append(count); OgH Wmb
buff.append(",p:").append(p); d\Dxmb]o
buff.append(",nump:").append(num); )sNtwSl^
buff.append(",results:").append v/yk T9@;
/.WD'*H
(results); gn(n</\/O
buff.append("}"); 3v0)oK
return buff.toString(); QX(:!b
} 2?
!b!
;y k@`<
} TR)'I
1YnDho;~
IHagRldG