Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 n 8OdRv
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 *UL|{_)c
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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 i{FC1tVeL_
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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 k+R?JWC:
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分页支持类: =ci5&B?
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java代码: XX[Wwt
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package com.javaeye.common.util; y yR8VO{
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import java.util.List; 4e#K.HU_
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publicclass PaginationSupport { 3Q~&xNf
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publicfinalstaticint PAGESIZE = 30; ^%X\ }><
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privateint pageSize = PAGESIZE; S2
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privateList items; e(\S,@VN2
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privateint totalCount; iY'hkr w
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privateint[] indexes = newint[0]; rLVc<595
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privateint startIndex = 0; vuf|2!kh/
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public PaginationSupport(List items, int |8B[yr.b
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totalCount){ ;k0*@c*
setPageSize(PAGESIZE); k8TMdWW
setTotalCount(totalCount); ~VKw%WK
setItems(items); Jj!T7f*-GX
setStartIndex(0); KR*/ye G!E
} wa C%o%fD
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public PaginationSupport(List items, int ~BC5no
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totalCount, int startIndex){ eXYR/j<8
setPageSize(PAGESIZE); ,RZktWW_
setTotalCount(totalCount);
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setItems(items); ,oCr6 ]
setStartIndex(startIndex); =k'dbcfO$9
} 7Q`4*H6
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public PaginationSupport(List items, int bke 1 F
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totalCount, int pageSize, int startIndex){ 0V^?~ex
setPageSize(pageSize); Pw")|85
setTotalCount(totalCount); r~sGot+sQA
setItems(items); ,FTF@h-Cs
setStartIndex(startIndex); Na=q(OKN
} m*'#`v Ibb
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publicList getItems(){ G/y< bPQ
return items; qAm%h\
} i@2?5U>h
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publicvoid setItems(List items){ K46\Rm_:B;
this.items = items; *"#>Ov>
} = *sP,
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publicint getPageSize(){ xkX,
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return pageSize; m,pDjf
} eq"~by[Uq
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publicvoid setPageSize(int pageSize){ ;{>z\6N
this.pageSize = pageSize; (Yx rZ_F'b
} ua0k)4|
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publicint getTotalCount(){ '\9A78NV{;
return totalCount; $tb$gO
} `0sa94H1[
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publicvoid setTotalCount(int totalCount){ 6rRPqO
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if(totalCount > 0){ pdE=9l'
this.totalCount = totalCount; *bZV4}
int count = totalCount / }g3)z%Xe'[
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pageSize; TfJB;
if(totalCount % pageSize > 0) Jl}$)'
count++; 7Npz
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indexes = newint[count]; #fa~^]EM]
for(int i = 0; i < count; i++){ md<%Z4+
indexes = pageSize * D[U5SS!)
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i; Y2Tg>_:t
} = uOFaZ4
}else{ T9u/|OP
this.totalCount = 0; @$Y`I{Xf
} ];IUiS1
} L!5%;!>.P
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publicint[] getIndexes(){ xGz$M@f
return indexes; Lx2.E1?@
} KaOS!e'
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publicvoid setIndexes(int[] indexes){ ]` 3;8,
this.indexes = indexes; h(>4%hF
} G:f]z;Xdp
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publicint getStartIndex(){ (/c9v8Pr(7
return startIndex; BjJ+~R
} A`IE8@&Z'
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publicvoid setStartIndex(int startIndex){ :)bm+xWFF
if(totalCount <= 0) kIM* K%L}
this.startIndex = 0; \U,.!'+
elseif(startIndex >= totalCount) "]`!#5j^WP
this.startIndex = indexes Zs)HzOP)9
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[indexes.length - 1]; entO"~*EX
elseif(startIndex < 0) p.&FK'&[0
this.startIndex = 0; Vhv<w
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else{ ^O4.$4t|
this.startIndex = indexes
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[startIndex / pageSize]; 03[(dRK>=
} #O qfyY!
} 8D)2/$NsY}
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publicint getNextIndex(){ 7>v1w:cC]
int nextIndex = getStartIndex() + DTPYCG&%
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pageSize; O0c#-K.f
if(nextIndex >= totalCount) }JoCk{<31
return getStartIndex(); RB]K?
else oicett=5
return nextIndex; J&,N1B
} V>#iR>w_4,
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publicint getPreviousIndex(){ SB5[PDL_q
int previousIndex = getStartIndex() - V\axOz!
8+^?<FKa
pageSize; y w"Tw
if(previousIndex < 0) TmS;ybsG
return0; '&L ;y
else 6bL+q`3>
return previousIndex; 2N]u!S ;d
} jRz2l`~7#
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} w, 0tY=h6
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抽象业务类 ?DVO\Cp
java代码: \jn[kQ+pJ
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/** a!"81*&4#
* Created on 2005-7-12 Zl]Zy}p* +
*/ cvn4Q- ^
package com.javaeye.common.business; Oq{&hH/'}
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import java.io.Serializable; 7>-y,?&
import java.util.List; y:!MWZ
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import org.hibernate.Criteria; GE$spx
import org.hibernate.HibernateException; &fYx0JT
import org.hibernate.Session; gF%lwq
import org.hibernate.criterion.DetachedCriteria; qE6:`f
import org.hibernate.criterion.Projections; b2
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import 52B
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org.springframework.orm.hibernate3.HibernateCallback; -@ #b<"1
import sm}q&m]ad
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org.springframework.orm.hibernate3.support.HibernateDaoS ;VS;),h/
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upport; L@?Dmn'v
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import com.javaeye.common.util.PaginationSupport; ]}9cOb%I
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public abstract class AbstractManager extends E66e4?"
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HibernateDaoSupport { ~fsAPIQ
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privateboolean cacheQueries = false; `Oys&]vb
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privateString queryCacheRegion; U;Hu:q*
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publicvoid setCacheQueries(boolean W<;i~W
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cacheQueries){ O:q}<ljp
this.cacheQueries = cacheQueries; D`e!CprF
} .CI]8O"3y
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publicvoid setQueryCacheRegion(String mT@UQCG
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queryCacheRegion){ MLmc]nL=
this.queryCacheRegion = }K;@$B6,@
,e>C)wq;
queryCacheRegion; qYIBP?`g
} FHM^x2
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publicvoid save(finalObject entity){ 3Q[]lFJ}F
getHibernateTemplate().save(entity); sx8mba(
} Rjo6Pd{d<
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publicvoid persist(finalObject entity){ /j
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getHibernateTemplate().save(entity); 4_PMl6qo
} 7r"!&P*,
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publicvoid update(finalObject entity){ *|$s0ga C
getHibernateTemplate().update(entity); 4,FkA_k
} zDa*n:S
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publicvoid delete(finalObject entity){ MnKEZ: 2
getHibernateTemplate().delete(entity); z^~uq:
} aChY5R
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publicObject load(finalClass entity, z2!NBOv
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finalSerializable id){ 0g]ABzTn
return getHibernateTemplate().load d7Q. 'cyQ
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(entity, id); <6p{eGAQV
} a<!g*UVL0M
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publicObject get(finalClass entity, Ofqe+C
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finalSerializable id){ "793R^Tz
return getHibernateTemplate().get 6g akopZO
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(entity, id); ]}>GUXe)^
} Fhxg^
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publicList findAll(finalClass entity){ ?3KI}'}EM
return getHibernateTemplate().find("from ]3
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" + entity.getName()); UfcM2OmbK
} \iowAo$
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publicList findByNamedQuery(finalString n6Q 3X
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namedQuery){ :Oq!.uO
return getHibernateTemplate +/Y)s5@<
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().findByNamedQuery(namedQuery); L>@0Nne7
} pk;bx2CP8
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publicList findByNamedQuery(finalString query, rK=[&k
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finalObject parameter){ "]MF =-v
return getHibernateTemplate c$uV8_ V
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().findByNamedQuery(query, parameter); P7u5Ykc*
} Pq7YJ"Z?:
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publicList findByNamedQuery(finalString query, aN;L5;m#>{
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finalObject[] parameters){ S'3l<sY
return getHibernateTemplate .6vQWt7@
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().findByNamedQuery(query, parameters); m?<C\&)6x
} 00b
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publicList find(finalString query){ (''`Ce
return getHibernateTemplate().find 3)Paf`mr
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(query); Z71"d"
} O^:Rm=,$
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publicList find(finalString query, finalObject 4qyL' \d[
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parameter){ 6x[gg !;85
return getHibernateTemplate().find y'4=
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(query, parameter); (V e[FhA
} \f{C2d/6j
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public PaginationSupport findPageByCriteria bcj7.rh]'h
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(final DetachedCriteria detachedCriteria){ YToRG7X#
return findPageByCriteria EzG7RjW
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); _/MKU!\l
} %? RX}37K
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public PaginationSupport findPageByCriteria z),l&7
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(final DetachedCriteria detachedCriteria, finalint `^w5/v#
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startIndex){ Wigm`A=,r
return findPageByCriteria _Thc\{aV#
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(detachedCriteria, PaginationSupport.PAGESIZE, U'lrdc"Q
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startIndex); (6JD<pBm
} L2K4nTA
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public PaginationSupport findPageByCriteria Jnv91*>h8
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(final DetachedCriteria detachedCriteria, finalint e1+
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pageSize, m0\(a_0V
finalint startIndex){ ,P9B8oIq
return(PaginationSupport) <cWo]T`X!
k,q` ^E8k
getHibernateTemplate().execute(new HibernateCallback(){ !^\|r<2M
publicObject doInHibernate Q$RP2&
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(Session session)throws HibernateException { 9$d (`-&9p
Criteria criteria = AY *
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detachedCriteria.getExecutableCriteria(session); Gzm[4|nO^
int totalCount = ^{Mx?]z
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((Integer) criteria.setProjection(Projections.rowCount l kl#AH
}*0%wP
()).uniqueResult()).intValue(); JXvHsCd?
criteria.setProjection *!nS4[d
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(null); Y4b"(ZhM_
List items = wV(_=LF
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criteria.setFirstResult(startIndex).setMaxResults U;{VL!
g[Yok`e[
(pageSize).list(); \W$>EH
PaginationSupport ps = 1zl@$ Nt
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new PaginationSupport(items, totalCount, pageSize, }RM?gE
ok[R`99
startIndex); ,rTR
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return ps; 9$Hgh7'hvs
} [.6uw=;o
}, true); *Jp>)>
} >Axe7<l
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public List findAllByCriteria(final 'm^]X3y*
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DetachedCriteria detachedCriteria){ ^AF~k#R
return(List) getHibernateTemplate M2Jb<y]
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().execute(new HibernateCallback(){ kB9@
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publicObject doInHibernate B|K^:LUk9
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(Session session)throws HibernateException { / ?'FSWDU
Criteria criteria = Vk2%yw>
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detachedCriteria.getExecutableCriteria(session); \t`Vq JLyu
return criteria.list(); wp'[AR}
} df {\O*6
}, true); [P0c,97_
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} K4H27SH
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public int getCountByCriteria(final xJ\>;$CY
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DetachedCriteria detachedCriteria){ 6CNxb
Integer count = (Integer) kfkcaj4l]
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getHibernateTemplate().execute(new HibernateCallback(){ TK Ec^
publicObject doInHibernate 0NyM|
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(Session session)throws HibernateException { 5
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Criteria criteria = a]?o"{{+
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detachedCriteria.getExecutableCriteria(session); ,4S6F HK
return F{
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criteria.setProjection(Projections.rowCount .J2tm2]"EZ
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()).uniqueResult(); `"eIzLc%o6
} e]3b0`E
}, true); %j;mDR95
return count.intValue(); B3@\Ua)
} ?w>-ya
} *nV*WUS3
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用户在web层构造查询条件detachedCriteria,和可选的 crr#tad.
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 hta y-
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PaginationSupport的实例ps。 xC -&<s
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ps.getItems()得到已分页好的结果集 URDXyAt
ps.getIndexes()得到分页索引的数组 ]E}eM@xdD
ps.getTotalCount()得到总结果数 1\%2@NR
ps.getStartIndex()当前分页索引 ]"VxEpqhM
ps.getNextIndex()下一页索引 DkeFDzQ5
ps.getPreviousIndex()上一页索引 ?m:,hI
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 e>!=)6[*
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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 +L|-W9"@3
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一下代码重构了。 @ACq:+/Qc
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我把原本我的做法也提供出来供大家讨论吧: Y3?)*kz%
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首先,为了实现分页查询,我封装了一个Page类: +$
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java代码: sJ5Ws%q
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/*Created on 2005-4-14*/ yp"h$
package org.flyware.util.page; O("13cU
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/** ?[c{pb,|
* @author Joa S$ Z?T
* c,FZ{O@
*/ ]lZg }7h
publicclass Page { EdC/]
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/** imply if the page has previous page */ Fu[<zA^
privateboolean hasPrePage; W>y&
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/** imply if the page has next page */ :fA|J!^b[
privateboolean hasNextPage;
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/** the number of every page */ w,eW?b
privateint everyPage; -xL^UcG0
fHiS'R
/** the total page number */ H_>9'(
privateint totalPage; lkJ"f{4f
6\vaR#
/** the number of current page */ ]\(Ho
privateint currentPage; rBZ0Fx$/[
6d/1PGB
/** the begin index of the records by the current e&-MP;kgW9
g+3_ $qIQ+
query */ aI_[h
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privateint beginIndex; _t?#
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/** The default constructor */ H$pgzNL
public Page(){ W5~!)Ec
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} nV`W0r(f'
4^d).{&X
/** construct the page by everyPage A..`?oGj
* @param everyPage \w(0k^<7
* */ /E i e5p
public Page(int everyPage){ 2v#gCou
this.everyPage = everyPage; Q&"oh
} NzeiGj
SZ7; }
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/** The whole constructor */ fL]jk1.Xv-
public Page(boolean hasPrePage, boolean hasNextPage, n.R"n9v`
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int everyPage, int totalPage,
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int currentPage, int beginIndex){ 7VWy1
this.hasPrePage = hasPrePage; T=@Ygjk
this.hasNextPage = hasNextPage; 6:`[Fi
this.everyPage = everyPage; rR#wbDr5
this.totalPage = totalPage; ?8U]UM6Tu4
this.currentPage = currentPage; U\-.u3/
this.beginIndex = beginIndex; Nl9}*3r
} +5H1n(6)
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/** I|_U|H!`
* @return ;Ngu(es6
* Returns the beginIndex. -P28pVX`
*/ 7e6;
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publicint getBeginIndex(){ Qk].^'\
return beginIndex; o(g}eP,g}
} YR}
P;
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/** v$i[dZSN[
* @param beginIndex VUE6M\&z>
* The beginIndex to set. \" W_\&X
*/ ^RO_B}n3
publicvoid setBeginIndex(int beginIndex){ p^ojhrr
this.beginIndex = beginIndex; #_}r)q
} i!9|R)c
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/** nt*nTtcE
* @return bTN0 n
* Returns the currentPage. Msea kF
*/ YoEL|r|
publicint getCurrentPage(){ BavGirCp
return currentPage; K$(LiP
} / %:%la%
w`;>+_ E7
/** mfpL?N
* @param currentPage iYHCa }
* The currentPage to set. yC<[LH
*/ ?}g#Mc
publicvoid setCurrentPage(int currentPage){ C-6m[W8S
this.currentPage = currentPage; Ivue"_i;!
} q&`>&k
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/** -<GSHckD
* @return =u^{Jvl[
* Returns the everyPage. ttaYtV]]
*/ e}Xmb$
publicint getEveryPage(){ |zaYIVE[
return everyPage; +,BJ4``*k
} L% cr `<~
b=-LQkcZhK
/** 4M4oI .
* @param everyPage j%y)%4F8
* The everyPage to set. r{~@hd'Aj
*/ D>~S-]
publicvoid setEveryPage(int everyPage){ Q:4euhz*
this.everyPage = everyPage; (2vf
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} WKwU:im
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/** u(`,7 o "
* @return VP<_~OLc
* Returns the hasNextPage. ;.g <u
*/ AX= 4{b'
publicboolean getHasNextPage(){ B-
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return hasNextPage; />i~No#Xm
} ~YX!49XfHh
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/** D`G ;kp
* @param hasNextPage pzPm(M1^X
* The hasNextPage to set. /` j~r;S
*/ ct3^V M&/
publicvoid setHasNextPage(boolean hasNextPage){ JTxHM?/G
this.hasNextPage = hasNextPage; dGrm1w
} l]GUQcN=
cTR@
:sm
/** TZ]D6.mD
* @return i8tH0w/(M
* Returns the hasPrePage. !P6\-.
*/ XA$Z7_gu3
publicboolean getHasPrePage(){ wV9[Jl\Z
return hasPrePage; z}" Xt=G?
} uH 6QK\
d`_X$P4y
/** $
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* @param hasPrePage ;LBq!
* The hasPrePage to set. >4zH\T!
*/ `qjiC>9
publicvoid setHasPrePage(boolean hasPrePage){ .!\NM&E
this.hasPrePage = hasPrePage; Vko1{$}t
} 2f8Cs$Opb
vB :_|B
/** er0hf2N]
* @return Returns the totalPage. K'`N(WiL
* @"6dq;"
*/ g]=w_
publicint getTotalPage(){ X"KX_)GZD
return totalPage; 483BrFV
} y8$TU;
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/** xJvM
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* @param totalPage kT!Y~c
* The totalPage to set. O>=D1no*
*/ $_6DvJ0
publicvoid setTotalPage(int totalPage){ 6o_t;cpT
this.totalPage = totalPage; %lw!4Z\gg
} Y6|8;2E
a8#6}`|C?
} hJ+;N
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5
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 1*<m,.$
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个PageUtil,负责对Page对象进行构造: OI</o0Ca
java代码: H@o3u>}
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/*Created on 2005-4-14*/ ~p^&`FA
package org.flyware.util.page; o8c4h<,
daS l.:1
import org.apache.commons.logging.Log; X8aNl"x
import org.apache.commons.logging.LogFactory; Xi`K`Cu+
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/** + HvEiY
* @author Joa wd&Tf
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* Kt5;GUV
*/ |9cJO@
publicclass PageUtil { nw|ls2
H.#<&5f
privatestaticfinal Log logger = LogFactory.getLog >DqV^%2l
=z`GC1]bL
(PageUtil.class); f/Cf2
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/** D/wX
* Use the origin page to create a new page G*.}EoA
* @param page AB92R/
* @param totalRecords :(gZ\q">k
* @return ha_&U@w
*/ oqeA15k$
publicstatic Page createPage(Page page, int U'8+YAgc
!Wn^B|
totalRecords){ i!5zHn
return createPage(page.getEveryPage(), b7&5>Q/g
62{(i'K
page.getCurrentPage(), totalRecords); $e>(M&9,
} I6!~(ND7
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/** q^5j&jx Vl
* the basic page utils not including exception iK&s_}i:
701ei;
handler vhe[:`=a
* @param everyPage A|3'9iL{9
* @param currentPage 36ygI0V_
* @param totalRecords 3^NHVg
* @return page l0hcNEj{W
*/ ,ru2C_LQ
publicstatic Page createPage(int everyPage, int |^: A,%>
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currentPage, int totalRecords){ AP1Eiv<Hub
everyPage = getEveryPage(everyPage); $H}G'LqiG
currentPage = getCurrentPage(currentPage); O"%b@$p\L
int beginIndex = getBeginIndex(everyPage, \v|nRn,`-
N$cm;G=]
currentPage); U tb"6_
int totalPage = getTotalPage(everyPage, of? hP1kl[
ep|>z#1
totalRecords); LU'<EXUbY
boolean hasNextPage = hasNextPage(currentPage, ~cC=DeX
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Pr&O9
totalPage); ."HDUo2D7
boolean hasPrePage = hasPrePage(currentPage); &~9'7 n!
J/OG\}
returnnew Page(hasPrePage, hasNextPage, ,0j7qn@tm
everyPage, totalPage, [w>T.b
currentPage, o|r8x_!+
2L\}
beginIndex); :
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} DcjF$E
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privatestaticint getEveryPage(int everyPage){ Q}/2\Q=)j
return everyPage == 0 ? 10 : everyPage; F ?APDGAN
} by*?PhfF
1W@ C]n4
privatestaticint getCurrentPage(int currentPage){ ,q[aV 6kO
return currentPage == 0 ? 1 : currentPage; c)L1@ qdZ
} aHhr_.>X
g3fxf(iY(
privatestaticint getBeginIndex(int everyPage, int 'r/+za:2
?o0ro?9j
currentPage){ y~16o
return(currentPage - 1) * everyPage; _BC%98:WP
} 6R`q{}.
1]DPy+
privatestaticint getTotalPage(int everyPage, int 1$+-?:i C
/"Z6\T9
totalRecords){ moop.}O<
int totalPage = 0; NA=I7I@
"#ctT-g`6
if(totalRecords % everyPage == 0) PM(M c]6
totalPage = totalRecords / everyPage; @^O+ulLJ,]
else LtJl\m.th
totalPage = totalRecords / everyPage + 1 ; ftaGu-d%
Q/u2Q;j>
return totalPage; =qg;K'M5
} XWuHH;~*L
e-@.+f2CC
privatestaticboolean hasPrePage(int currentPage){ ;$il_xA)\>
return currentPage == 1 ? false : true; tAi
~i;?
} f+WN=-F\
>14x.c
privatestaticboolean hasNextPage(int currentPage, ~_XK<}SK
NKy Ksu
int totalPage){ T09'qB
return currentPage == totalPage || totalPage == BQOit.
be->ofUYgs
0 ? false : true; sY%nPf~9q'
} XCP/e p
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y\C_HCU H
} Y|3n^%I
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(q
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|| }'
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。 A,u}p rwH
GN=ugP 9
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 ';vLj1v
0W6jF5T
做法如下: wG-lR,glb
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 xNAa,aMM
JtbwY@R
的信息,和一个结果集List: ->u}b?aF
java代码: /=i+7^
kc:>[ {9
Vx#n0z
/*Created on 2005-6-13*/ LJ{P93aq`^
package com.adt.bo; jqJ't)N
vIQu"J&fE
import java.util.List; Ia%S=xU{=
{Y6;/".DM
import org.flyware.util.page.Page; sWGc1jC?.F
`JZ`j7f
/** cq0#~20
* @author Joa ,?KN;~t#vz
*/ ~2L]K4Z^
publicclass Result { P: QSr8K
J9V,U;"\
private Page page; `%<^$Ng;
JO =kfWW
private List content; )r`F}_CEL
a
j13cC$
/** Js0h lWu
* The default constructor n%&+yg
*/ sqE? U*8.-
public Result(){ TJ`Jqnh
super(); ?Mj@;O9>'
} Xt$o$V
i!7|YAu
/** 7|Bg--G1
* The constructor using fields 2)4oe
* ZmKxs^5S
* @param page Pu `;B
* @param content zv>7;En3
*/ nm{J
public Result(Page page, List content){ Jr.4Y>;}e3
this.page = page; wxW\L!@
this.content = content; w\`u|f;Aq
} /xh/M@G3
Bf+7;4-
/** 6U?z
* @return Returns the content. UWIw/(Mv/]
*/ ]`H8r y2
publicList getContent(){ >oasA2S
return content; n*nsFvt%o
} *)82iD
L>>Cx`ASi
/** $^ZugD
* @return Returns the page. a%NSL6
*/ r{
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public Page getPage(){ |x/00XhS
return page; j" ~gEGfK
} Fo$'*(i
Pp~:e}
/** e>~7RN
* @param content %D
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* The content to set. y{O817 \
*/ Api<q2@R
public void setContent(List content){ 5rPK7Jh`B
this.content = content; rc ()Eo50
} m{{8#@g
bS"zp6Di
/** :W*']8 M-
* @param page `p\@b~GM
* The page to set. Eu)(@,]we
*/ M#a1ev
publicvoid setPage(Page page){ IyJHKDFk
this.page = page; .|Y&,?k|Y
} &8R!`uh1
} 6(as.U>K
f tE2@}
U,e'vS{
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2. 编写业务逻辑接口,并实现它(UserManager, rwh,RI)
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UserManagerImpl) hiBZZ+^[
java代码: guc[du
mNDz|Ln
X+LG Z4]D
/*Created on 2005-7-15*/ vWpoaz/w
package com.adt.service; v62O+{
_j Ck)3KO
import net.sf.hibernate.HibernateException; `j)S7KN
/t"FZ#
import org.flyware.util.page.Page; "Di8MMGOY
noL&>G
import com.adt.bo.Result; {>rGe#Vu
eF=cMC
/** ?=#vp /
* @author Joa :Y)jf
*/ ^]{m*bEkR
publicinterface UserManager { 4SDUTRoa
Z\. n6
public Result listUser(Page page)throws K}e:zR;;^
rO3.%B}
HibernateException; x4=Sm0Ro|V
[QZ g=."
} ]q pLaBD
INjr$'*
l\t\DX"s_
9Q/t+
o4PJ9x5R!
java代码: p()#+Xy
|^k&6QO5
l2Pry'3
/*Created on 2005-7-15*/ dgp1 B\
package com.adt.service.impl; 7H!/et?S,
u/_TR;u=q
import java.util.List; K6d2}!5
/?*GJN#
import net.sf.hibernate.HibernateException; #X t|"Z
JG/Pc1aK
import org.flyware.util.page.Page; UI%Z`.&
import org.flyware.util.page.PageUtil; o|G[/o2
?DrA@;IB
import com.adt.bo.Result; A29R5
import com.adt.dao.UserDAO; #UesXv
import com.adt.exception.ObjectNotFoundException; !YVGT
<
import com.adt.service.UserManager; cKEDRX3
%iR"eEE
/** r7^oqEp@B
* @author Joa $+
*/ 4^(aG7
publicclass UserManagerImpl implements UserManager { Q&]f9j_
f"RS,]
private UserDAO userDAO; /P%OXn$i/
Ygq;jX
/** Lvd es.0|
* @param userDAO The userDAO to set. B?
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*/ >r\q6f#J4
publicvoid setUserDAO(UserDAO userDAO){ vdIert?p
this.userDAO = userDAO; SxI-pH'
} Y?v{V>;*A
MSaOFv_Q
/* (non-Javadoc) MAQ(PIc>T
* @see com.adt.service.UserManager#listUser 10d.&vNw
pf$gvL
(org.flyware.util.page.Page) .]w=+~h
*/ ~JQ6V?fucD
public Result listUser(Page page)throws <&RpGAk%I
Jo''yrJpB
HibernateException, ObjectNotFoundException { ]{|
wU.
int totalRecords = userDAO.getUserCount(); ]?%S0DO*
if(totalRecords == 0) M;LR$'cP
throw new ObjectNotFoundException Ge7Uety
E?-
~*T
("userNotExist"); 4;*jE (
page = PageUtil.createPage(page, totalRecords); wZfY~
List users = userDAO.getUserByPage(page); %uw7sGz\
returnnew Result(page, users); -v! ;
} Z 4QL&?U
m6uFmU*<M}
} MY}/h@
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k+BY 3a
xLSf
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K7X*N
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 n^|SN9_r
IIN,Da;hD
询,接下来编写UserDAO的代码: 2HO2
3. UserDAO 和 UserDAOImpl: D-FT3Culw
java代码: bFhZSk)
2@W`OW Njm
;nrkC\SYh:
/*Created on 2005-7-15*/ pgQ^w0BQV
package com.adt.dao; R^B8** N
Dn)B19b
import java.util.List; x_ t$*
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O{^
import org.flyware.util.page.Page; *j(UAVp
d_!}9
import net.sf.hibernate.HibernateException; ep4?;Qmho
WcQkeh3n
/** BiDyr
* @author Joa #"8'y
*/ +:W/=C
d(h
publicinterface UserDAO extends BaseDAO { k<