Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 'NWfBJm
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 VF+KR*
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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 p?02C#p
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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 wo3d#=
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分页支持类: >R'F,
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java代码: x'8x
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package com.javaeye.common.util; FUiRTRIYe
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import java.util.List; 8=!D$t\3
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publicclass PaginationSupport { -{("mR&]
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publicfinalstaticint PAGESIZE = 30; &5>Kl}7
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privateint pageSize = PAGESIZE; ?w$kue
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privateList items; ,<.V7(|t)
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privateint totalCount; D ;RiGW4
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privateint[] indexes = newint[0]; |NlO7aQ>2H
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privateint startIndex = 0; +V2F#fI/
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public PaginationSupport(List items, int (|2t#'m
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totalCount){ n3WlZ!$
setPageSize(PAGESIZE); aHD]k8m z
setTotalCount(totalCount); r-,%2y?
setItems(items); !M(xG%M-V
setStartIndex(0); 6 W/`07'
} -uS!\
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public PaginationSupport(List items, int <|HV. O/!
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totalCount, int startIndex){ j/DzCc p7
setPageSize(PAGESIZE); )+#` CIv
setTotalCount(totalCount); H8=N@l
setItems(items); IW5,7.
setStartIndex(startIndex); ,CJWO bn3
} "69s)~
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public PaginationSupport(List items, int :@Pl pFK
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totalCount, int pageSize, int startIndex){ !t"4!3
setPageSize(pageSize); w?L6!) oiz
setTotalCount(totalCount); b1I]>\
setItems(items); PrqlTT}Px
setStartIndex(startIndex); p%ki>p )E|
} gt)I(
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publicList getItems(){ Xg6Jh``
return items; 9X6h
} Ov@gh
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publicvoid setItems(List items){ {p2!|A&a
this.items = items; l$KA)xbI
} }dX*[I
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publicint getPageSize(){ <sbu;dQ`
return pageSize; )$2QZ
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} HZE#Ab*L
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publicvoid setPageSize(int pageSize){ =IZT(8
this.pageSize = pageSize; ,)cM3nu
} L(6d&t'|-R
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publicint getTotalCount(){ gT.sjd
return totalCount; vO^m;['
} )_90UwWpj
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publicvoid setTotalCount(int totalCount){ ,>a&"V^k
if(totalCount > 0){ fgTg7 m
this.totalCount = totalCount; qz_7%c]K[
int count = totalCount / LBeF&sb6
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pageSize; w{8xpAqm
if(totalCount % pageSize > 0) K-)]
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count++; (XTG8W sN
indexes = newint[count]; k=$TGqQY?
for(int i = 0; i < count; i++){ HQdxL*N%^
indexes = pageSize * FjHv
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i; Y(ykng
} 6GlJ>r+n
}else{ ^CYl\.Y@
this.totalCount = 0; v4TQX<0s
} ktXM|#
} :LQYo'@yB
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publicint[] getIndexes(){ P= BZ+6DS
return indexes; ^oz3F]4,g
} KAJi
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publicvoid setIndexes(int[] indexes){ &J]K3w1p
this.indexes = indexes;
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} y-b%T|p9
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publicint getStartIndex(){ u/0h$l
return startIndex; WDYeOtc
} NN{?z!
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publicvoid setStartIndex(int startIndex){ .NC!7+1m
if(totalCount <= 0) s]0{a.Cpv
this.startIndex = 0; !PlEO 2at
elseif(startIndex >= totalCount) Dj?> <@
this.startIndex = indexes [85spub&}
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[indexes.length - 1]; e2Pcm_Ahv*
elseif(startIndex < 0) D/gw .XYL
this.startIndex = 0; qBQ?HLK-
else{ G$"h&Xy1c
this.startIndex = indexes ?4} h&/
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[startIndex / pageSize]; i^&~?2
} jRlYU`?
} 7aRi5
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publicint getNextIndex(){ ?p{Nwl#
int nextIndex = getStartIndex() + y14;%aQN
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pageSize; 1-uxC^u?|#
if(nextIndex >= totalCount) m9WDT
return getStartIndex(); J4C.+![!Ah
else +o{R _
return nextIndex; `?rSlR@+[I
} U}[d_f
NNR`!Pty
publicint getPreviousIndex(){ |s(FLF -
int previousIndex = getStartIndex() - W\,s:6iqz
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pageSize; {]!mrAjD
if(previousIndex < 0) f}ji?p
return0; \)904W5R
else 2]jn '4
return previousIndex; Sv#XIMw{,
} XEp{VC@=
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} 4he GnMD
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抽象业务类 P )"m0Lu<
java代码: 2;`1h[,-^
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/** $9#H04.x
* Created on 2005-7-12 6<SAa#@ey
*/ %lhEM}Sm
package com.javaeye.common.business; c|y(2K)o[=
6vo;!V6
import java.io.Serializable; }OR@~V{Gj
import java.util.List; G6P?2@
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import org.hibernate.Criteria; ,eW%{[g(
import org.hibernate.HibernateException; ^ogt+6c
import org.hibernate.Session; GW@;}m(
import org.hibernate.criterion.DetachedCriteria; iN\4gQ!
import org.hibernate.criterion.Projections; N,AQsloL7
import NO>w+-dGS
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org.springframework.orm.hibernate3.HibernateCallback; 8 +/rlHp
import [A~xy'T
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org.springframework.orm.hibernate3.support.HibernateDaoS -#[a7',Z;
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upport; z+wA
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import com.javaeye.common.util.PaginationSupport; &j`} vg
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public abstract class AbstractManager extends '~<m~UXvD#
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HibernateDaoSupport { Wx}8T[A}
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privateboolean cacheQueries = false; yCR?UH;
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privateString queryCacheRegion; \)N9aV
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publicvoid setCacheQueries(boolean gQg"j)
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cacheQueries){ t;Sb/ 3
this.cacheQueries = cacheQueries; NjScc%@y
} e7Z32P0ls
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publicvoid setQueryCacheRegion(String Su7?;Oh/yI
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queryCacheRegion){ &*,#5.
this.queryCacheRegion =
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queryCacheRegion; =E4LRKn
} u#$]?($}d
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publicvoid save(finalObject entity){ <tNBxa$gS
getHibernateTemplate().save(entity); Qf+\;@
} y/cvQY0pU
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publicvoid persist(finalObject entity){ ?k&Vy
getHibernateTemplate().save(entity); -q1??u
} _x'6]f{n
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publicvoid update(finalObject entity){ F=e8 IUr
getHibernateTemplate().update(entity); \BTODZ:h
} zuad~%D<I
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publicvoid delete(finalObject entity){ T|e u
getHibernateTemplate().delete(entity); 9igiZmM
} 4y?n
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publicObject load(finalClass entity, p!7FpxZY
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finalSerializable id){ ,{u
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return getHibernateTemplate().load <I\/n<*
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(entity, id); O7m(o:t x3
} mbTEp*H
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publicObject get(finalClass entity, %KhI>O<
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finalSerializable id){ i Dp)FQ$
return getHibernateTemplate().get *20jz<
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(entity, id); IqaT?+O\?r
} {yHCXFWlS
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publicList findAll(finalClass entity){ v\gLWq'
return getHibernateTemplate().find("from 5oW!YJg
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" + entity.getName()); P|tO<t6/9*
} B$fPgW-
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publicList findByNamedQuery(finalString 1~Y<//5E
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namedQuery){ {9&;Q|D z
return getHibernateTemplate
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().findByNamedQuery(namedQuery); i(%W_d!
} /tx]5`#@7]
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publicList findByNamedQuery(finalString query, I(L,8n5
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finalObject parameter){ |^"1{7)
return getHibernateTemplate )Xz,j9GzJS
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().findByNamedQuery(query, parameter); s 8jV(P(O
} "Y
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publicList findByNamedQuery(finalString query, BDW^7[n
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finalObject[] parameters){ s^G.]%iU
return getHibernateTemplate A@!qv#'
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().findByNamedQuery(query, parameters); NqazpB*
} w7.V6S$Ga
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publicList find(finalString query){ D09Sg%w
return getHibernateTemplate().find Ha0M)0Anv
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(query); /!yU!`bY
} OhQgF
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publicList find(finalString query, finalObject Q^9_'t}X
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parameter){ n`B:;2X,
return getHibernateTemplate().find Ct <udO
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(query, parameter); *MhRW,=
} p?%y82E
c \J:![x
public PaginationSupport findPageByCriteria ul6]!Iy
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(final DetachedCriteria detachedCriteria){ ?4#Li~q
return findPageByCriteria F4-$~v@
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); w>s,"2&5J
} .GPT!lDc
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public PaginationSupport findPageByCriteria j|DsG,
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(final DetachedCriteria detachedCriteria, finalint XSwl Tg
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startIndex){ 7?!d^$B
return findPageByCriteria ed{ -/l~j
z [}v{
(detachedCriteria, PaginationSupport.PAGESIZE, .]Y$o^mf
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startIndex); 4<w.8rR:A
} JQ_sUYh~3
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public PaginationSupport findPageByCriteria ,GhS[VJjR
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(final DetachedCriteria detachedCriteria, finalint X6w6%fzOH>
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pageSize, :S{BbQ){]
finalint startIndex){ \j}ZB<.>
return(PaginationSupport) }z'8Bu
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getHibernateTemplate().execute(new HibernateCallback(){ $lfn(b,
publicObject doInHibernate aB2FC$z
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(Session session)throws HibernateException { g-4M3of
Criteria criteria = DZ3wCLQtK
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detachedCriteria.getExecutableCriteria(session); hlvK5Z
int totalCount = 3)t.p>VgO
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((Integer) criteria.setProjection(Projections.rowCount EqkN3%IG
c)6m$5]
()).uniqueResult()).intValue(); fZGX}T<)p-
criteria.setProjection .ljnDL/
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(null); jh?H.;**
List items = Y#ap*
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criteria.setFirstResult(startIndex).setMaxResults /Iu1L#
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(pageSize).list(); kf\PioD8
PaginationSupport ps = l?v86k
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new PaginationSupport(items, totalCount, pageSize, '6nAF
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startIndex); 0mYXv4
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return ps; ^lnK$i
} Di,^%
}, true); P8OaoPj
} M~Tuj1?
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public List findAllByCriteria(final \}yc`7T:L0
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DetachedCriteria detachedCriteria){ B{n,t}z
return(List) getHibernateTemplate ANAVn@ [
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().execute(new HibernateCallback(){ =g7x'
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publicObject doInHibernate ;Zcswt8]u
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(Session session)throws HibernateException { *?@?f&E/
Criteria criteria = ]\-A;}\e
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detachedCriteria.getExecutableCriteria(session); &@X<zWg
return criteria.list(); { T/[cu<
} T=
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}, true); \i>?q
} 3,_aAgeE
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public int getCountByCriteria(final W<h)HhyG
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DetachedCriteria detachedCriteria){ {r,.!;mHu
Integer count = (Integer) ]? c
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getHibernateTemplate().execute(new HibernateCallback(){ ydEoC$?0
publicObject doInHibernate .r=4pQ@#
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(Session session)throws HibernateException { rET\n(AJ
Criteria criteria = x;O[c3I
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detachedCriteria.getExecutableCriteria(session); 7(1|xYCx$
return ^x ]r`b
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criteria.setProjection(Projections.rowCount B9 _X;c
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()).uniqueResult(); ~Py`P'+
} ;DQ ZT
}, true); A7{\</Z
return count.intValue(); *xAqnk
} ~f2z]JLr:
} x`eo"5.$
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用户在web层构造查询条件detachedCriteria,和可选的 I.(,hFx;
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 olB.*#gA
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PaginationSupport的实例ps。 L tO!umM
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ps.getItems()得到已分页好的结果集 tn\yI!a
ps.getIndexes()得到分页索引的数组 /obfw^
ps.getTotalCount()得到总结果数 a@K%06A;'
ps.getStartIndex()当前分页索引 R`5.[?Dt
ps.getNextIndex()下一页索引 4d4ZT?V[
ps.getPreviousIndex()上一页索引 b<[Or^X
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 [T4J{y64Y
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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 S&5&];Ag
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一下代码重构了。 aH(J,XY
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我把原本我的做法也提供出来供大家讨论吧: ah$b[\#C
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首先,为了实现分页查询,我封装了一个Page类: bn&TF3b
java代码: "m$##X\
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/*Created on 2005-4-14*/ !<8W
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package org.flyware.util.page; ' ,wFTV&
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/** gnf8l?M
* @author Joa [ZwjOi:)
* lN
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*/ fCn^=8KOZ
publicclass Page { r| wS<cA2
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/** imply if the page has previous page */ #pow ub
privateboolean hasPrePage; z]y.W`i
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/** imply if the page has next page */ ,5p(T_V/
privateboolean hasNextPage; |Pax =oJ\M
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/** the number of every page */ ./Zk`-OBT
privateint everyPage; '?' l;#^i<
wh`"w7br
/** the total page number */ nsC3
privateint totalPage; Xf]d. :
k/_ 59@)
/** the number of current page */ )T2Caqs2
privateint currentPage; z6\UGSL
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/** the begin index of the records by the current 9!\B6=r y4
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query */ OX7M8cmc+
privateint beginIndex; Yx%Hs5}8
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/** The default constructor */ `UyG_;
public Page(){ {*" |#6-
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} !sP{gi#=
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/** construct the page by everyPage f|c{5$N!
* @param everyPage k@J&IJ
* */ >z>!Luw
public Page(int everyPage){ '3fu
this.everyPage = everyPage; s?}e^/"v
} H[$"+&q
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/** The whole constructor */ >uB#&Q
public Page(boolean hasPrePage, boolean hasNextPage, ]y'>=a|T
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int everyPage, int totalPage, 83\pZ1>)_
int currentPage, int beginIndex){ } 9Eg=%0v
this.hasPrePage = hasPrePage; B%b4v
this.hasNextPage = hasNextPage; u'DRN,h+
this.everyPage = everyPage; E7UU
this.totalPage = totalPage; sf87$S0
this.currentPage = currentPage; I3I/bofz
this.beginIndex = beginIndex; lvz7#f L~
} azp):*f("
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/** 5c0 ZRV#
* @return \'D0'\:vz
* Returns the beginIndex. @o _}g !9=
*/ mR:uj2*
publicint getBeginIndex(){ HyZqUbHa
return beginIndex; ZhaP2pC%4
} osAd1<EIC
*)T^ChD,
/** ~Ea} /Au
* @param beginIndex "ne?P9'hF
* The beginIndex to set. (Zrj_P`0[
*/ 0&|\N
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publicvoid setBeginIndex(int beginIndex){ E,U+o $
this.beginIndex = beginIndex; kJsN|=
} &
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/** E
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* @return WiR(;m<g
* Returns the currentPage. ] 72`};
*/ *zvx$yJ?
publicint getCurrentPage(){ (exa<hh
return currentPage; b9HtR -iR;
} 6j]0R*B7`Q
m8hk:4Ae
/** g7`LEF <A
* @param currentPage <)c)%'v
* The currentPage to set. Fj3a.'
*/ /]Md~=yNp
publicvoid setCurrentPage(int currentPage){ Yu^4VXp~M%
this.currentPage = currentPage; yI
} ,f'CD{ E
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/** 6}Ci>_i4#
* @return 37.S\gO]
* Returns the everyPage. K;H&n1
*/ f+)L#>Gl?
publicint getEveryPage(){ H3=qe I
return everyPage; s)D;a-F
} +_oJ}KI
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/** ZG8DIV\D7
* @param everyPage D.u{~
* The everyPage to set. mL{6L?
*/ "&?kC2Y|
publicvoid setEveryPage(int everyPage){ )g%d:xI
this.everyPage = everyPage; `e&Suyf4B
} G}raA%
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/** L^?qOylu
* @return +lcbi
* Returns the hasNextPage. 4p;`C
*/ :J&oX
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publicboolean getHasNextPage(){ qt"m
return hasNextPage; #f]SK[nR
} \V~eVf;~
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/** H40p86@M
* @param hasNextPage XK@E;Rv
* The hasNextPage to set. HBXOjr<,{
*/ 3;{kJQ
publicvoid setHasNextPage(boolean hasNextPage){ v$wIm, j
this.hasNextPage = hasNextPage; ;'@9[N9
} 0=1T.4+=
m&,(Jla
/** `d`T*_
* @return :OT0yA=U
* Returns the hasPrePage. d^
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*/ u `6:5k
publicboolean getHasPrePage(){ !z3jTv
return hasPrePage; /7F:T[
} X5$ Iyis
xY(*.T9K
/** %l[( Iw
* @param hasPrePage E]-/Zbvdv
* The hasPrePage to set. >}i E(
*/ hnhd{$2Z
publicvoid setHasPrePage(boolean hasPrePage){ JjTegQN
this.hasPrePage = hasPrePage; n;Vs_u/Nx
} <`r>h
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/** SoK
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* @return Returns the totalPage. MAPGJ"?
* lX4
x*
*/ "@0]G<H
publicint getTotalPage(){ +iRh
return totalPage; f6>b|k~
} JL{VD
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/** 7~.9=I'A
* @param totalPage V {ddr:]4
* The totalPage to set. u\;C;I-? '
*/ 3;]H1
1
publicvoid setTotalPage(int totalPage){ 8'io$6d=
this.totalPage = totalPage; +VOK%8,p
} BUXpCxQ
c 3)jccWTc
} M%P:n/j
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 r52gn(,
6mxfLlZ
个PageUtil,负责对Page对象进行构造: 00~mOK;1
java代码: ~V1E0qdAE
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/*Created on 2005-4-14*/ 56kI
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package org.flyware.util.page; kJT)r6
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import org.apache.commons.logging.Log; ],Do6
@M-
import org.apache.commons.logging.LogFactory; ope^~+c~\
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/** G3AesTT|
* @author Joa v;D~Pa
* ?J>
*/ 6q.Uhe_B
publicclass PageUtil {
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*Pf
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privatestaticfinal Log logger = LogFactory.getLog >@
.
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(PageUtil.class); 3{sVVq5Y
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/** [2M'PT3
* Use the origin page to create a new page wgGl[_)
* @param page Y\g3hM
* @param totalRecords uiR8,H9*M
* @return DT&@^$?
*/ 07{)?1cod4
publicstatic Page createPage(Page page, int t&e{_|i#+
}a(dyr`S
totalRecords){ 0*{%=M
return createPage(page.getEveryPage(), )|#sfHv7
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page.getCurrentPage(), totalRecords); ,/|T-Ka
} m#\dSl}
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/** )irEM
* the basic page utils not including exception 'YSHi\z ](
z9Rp`z&`E
handler 3eQ&F~S
* @param everyPage `*1p0~cu
* @param currentPage p>8D;#HmL
* @param totalRecords d<P\&!R(
* @return page NyNXP_8
*/ ' %o#q6O
publicstatic Page createPage(int everyPage, int WX3-\Y5E
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currentPage, int totalRecords){ WOL:IZX%
everyPage = getEveryPage(everyPage); sdw(R#GE
currentPage = getCurrentPage(currentPage); =]0&i]z[.
int beginIndex = getBeginIndex(everyPage, v0.#Sl-
> /caXvS
currentPage); )bscBj@
int totalPage = getTotalPage(everyPage, 3AN/
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totalRecords); |Ds1
boolean hasNextPage = hasNextPage(currentPage, -m~#Bq
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totalPage); :,6\"y-
boolean hasPrePage = hasPrePage(currentPage); aO4?m+
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returnnew Page(hasPrePage, hasNextPage, &6nWzF
everyPage, totalPage, ~oY^;/ j
currentPage, svH !1b
q^<?]8
beginIndex); II{&{S'HU
} Qd3 j%(
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privatestaticint getEveryPage(int everyPage){ 9CD_os\h
return everyPage == 0 ? 10 : everyPage; H$UcF1k<
} ~2-1 j
r3UUlR/Do
privatestaticint getCurrentPage(int currentPage){ 1/J=uH
return currentPage == 0 ? 1 : currentPage; 9~[Y-cpoi
} kMN~Y
k\?Ii<m
privatestaticint getBeginIndex(int everyPage, int &0JI!bR(
k@W1-D?
currentPage){ U&p${IcEm
return(currentPage - 1) * everyPage; nb%6X82Q
} @b2aNS<T
r\^b(rNe
privatestaticint getTotalPage(int everyPage, int m!HJj>GEo
RPRBmb940
totalRecords){ iGB}Il)
int totalPage = 0; Mb~F%_
JZyAXm%
if(totalRecords % everyPage == 0) $*fMR,~t&
totalPage = totalRecords / everyPage; |@4' <4t
else
7hPY_W
y
totalPage = totalRecords / everyPage + 1 ; zy
}$i?
v`1M[
return totalPage; 1p=]hC
} qY!Zt_Be6
HN|%9{VeB
privatestaticboolean hasPrePage(int currentPage){ &
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return currentPage == 1 ? false : true; _.8S&
} #AQV(;r7@
/IMFO:c
privatestaticboolean hasNextPage(int currentPage, 0n{=%Q
h~zT ydnH
int totalPage){ Ig>(m49d
return currentPage == totalPage || totalPage == brUF6rQ
II,8O
0 ? false : true; KPUV@eQ,
} {bY%# m
9XB 8VKu8
{I't]Qj_e
} nAdf=D'P
$f7l34Sf3
u]UOSf n
g[4WzDF*
_X
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上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 kE1TP]|
* r7rZFS
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 >fQMXfoY
*\F~[
做法如下: m ~$v;?i
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 X!EP$!
8YSAf+{FtK
的信息,和一个结果集List: R0*|Lo$6
java代码: X#^[<5
LZxNAua
4BpZJ~(p
/*Created on 2005-6-13*/ "VMz]ybi^
package com.adt.bo; 6(-N FnT
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import java.util.List; AH~E )S
Pa:|_IXA
import org.flyware.util.page.Page; 9_/:[N6|c|
FGq[\B
/** SXP]%{@R/
* @author Joa pOoEI+t
*/ iDqoa\
publicclass Result { _6vWF
dG ?*y
private Page page; q'Pf]
7;@]t^d=$
private List content; /Lr.e%
+9sQZB# (
/** [j+sC*
* The default constructor >Cq<@$I2EB
*/ mj7#&r,1l
public Result(){ G$('-3@i`w
super(); PXNuL&
} c'\dFb9a
gL/9/b4
/** `C'H.g\>2Q
* The constructor using fields j8:\%|
* J\=*#*rJ1
* @param page kvu)y`
* @param content ((%?`y
*/ P?P#RhvA1
public Result(Page page, List content){ )MT}+ai
this.page = page; tw)mepwB
this.content = content; ^E>3|du]O
} Q\sK"~@3
]JQULE)
/** $U-0)4yf
* @return Returns the content. vo{--+{ky!
*/ %JTpI`
publicList getContent(){ 4 s9LB
return content; t\O16O7S
} 4Ftu
N!tX<u~2
/** R[+<^s}p/
* @return Returns the page. SOaoo^,O
*/ <qt|d&
public Page getPage(){ +R75v )
return page; )NT*bLRPQ
} (A.C]hD
{R{=+2K!|k
/** _Y m2/3!
* @param content v4 E}D
* The content to set. 6Q5^>\Y
*/ X1_5KH
public void setContent(List content){ Bk{]g=DO
this.content = content; vtJJ#8a]
} DzRFMYBR
pT6$DB#
/** + Vdpy(
* @param page NDokSw-
* The page to set. 9%obq/Lb
*/ YtLt*Ig%
publicvoid setPage(Page page){ vW@=<aS Z
this.page = page; Y8t8!{ytg
} ?:9"X$XR
} 8zq=N#x
[{/jI\?v
#,'kXj
Lu%b9Jk
_DEjF)S
2. 编写业务逻辑接口,并实现它(UserManager, z` b,h\
'dc#F3
UserManagerImpl) |;{6&S
java代码: 7_[L o4_
-$Ih@2"6
~)M~EX&pK
/*Created on 2005-7-15*/ .x&%HA
package com.adt.service; MLp9y#
8H`[*|{'
import net.sf.hibernate.HibernateException; ]hV*r@d
9;If&uM
import org.flyware.util.page.Page; uhq8
,<X9 Y2B
import com.adt.bo.Result; RPbZ(.
F((4U"
/** 0<*<$U
* @author Joa Vi|#@tC'
*/ {Y1Ck5
publicinterface UserManager { tpx2IE
i"=\d
public Result listUser(Page page)throws b7ZSPXV
NwfVL4Xg
HibernateException; `@yp+8
PQE=D0
} DVeE1Q
A]3k4DLYS
\GU<43J2uo
b\5F ]r
!bP@n
java代码:
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o{[qZc_%
yIE!j%u
/*Created on 2005-7-15*/ z0Z%m@
package com.adt.service.impl; !dT4
!p/goqT~dY
import java.util.List; .jK4?}]
tT._VK]o&R
import net.sf.hibernate.HibernateException; Ew$C
;&9
*yGGBqd
import org.flyware.util.page.Page; 5`_SN74o
import org.flyware.util.page.PageUtil; qcRs$-J
f?)-}\[IR{
import com.adt.bo.Result; 5Ynd c)Z
import com.adt.dao.UserDAO; UGatWj
import com.adt.exception.ObjectNotFoundException; $Ygue5{c
import com.adt.service.UserManager; A?0Nm{O;3v
-ze J#B)C
/** x|29L7i
* @author Joa CU~PT.
*/ MUwMb!Z.s
publicclass UserManagerImpl implements UserManager { OcO3v'&
iJ|uvPCE
private UserDAO userDAO; Y|/ 8up
Y\hBd$lQ~
/** 6E}qL8'5x
* @param userDAO The userDAO to set. .c cp
*/ V G~Vs@c(
publicvoid setUserDAO(UserDAO userDAO){ KG{St{uJ
this.userDAO = userDAO; ,iwp,=h=
} IUct
EBmt9S
/* (non-Javadoc) EEL,^3KR
* @see com.adt.service.UserManager#listUser iam1V)V
LXCx~;{\
(org.flyware.util.page.Page) {7pli{`
*/ D3K8F@d
public Result listUser(Page page)throws <\S:'g"(
W!(LF7_!
HibernateException, ObjectNotFoundException { "^iYLQOC
int totalRecords = userDAO.getUserCount(); &Hnz8Or!
if(totalRecords == 0) FE;x8(;W8
throw new ObjectNotFoundException uvS)8-o&F
E<*xx#p
("userNotExist"); S`]k>'
l
page = PageUtil.createPage(page, totalRecords); "J3x_~,[4m
List users = userDAO.getUserByPage(page); ,v}k{( 16{
returnnew Result(page, users); [1H^3g
'
} -|9=P\U8S
\lNN Msd&
} v(%*b,^
-H-~;EzU
rU(+T0t?I
0Y5_PTWb+Y
@=f\<"$vt
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 t.C5+^+%
<
FAheE+
询,接下来编写UserDAO的代码: {+ b7sA3
3. UserDAO 和 UserDAOImpl: p{dj~ &v
java代码: Mrb)
W=4FFl[
m~ee/&T
/*Created on 2005-7-15*/ a"u0Q5J
package com.adt.dao; 3HK\BS
,9
a
import java.util.List; J9S>yLQK
6D_D' ;o
import org.flyware.util.page.Page; o3}3p]S\
IO:G1;[/2L
import net.sf.hibernate.HibernateException; FML(4BY,
w@fi{H(R
/** %e} Saf
* @author Joa bi;1s'Y<D
*/ g<
.qUBPKX
publicinterface UserDAO extends BaseDAO { Rbv;?'O$L
"-V"=t'
publicList getUserByName(String name)throws ?!/kZM_ts
%vi83%$'4
HibernateException; BING{ew
El"Q'(:/U
publicint getUserCount()throws HibernateException; zT-_5uZQ
lU8Hd|@-
publicList getUserByPage(Page page)throws K!l5coM
a7%]Y}$
HibernateException; |]*/R^1>2
;i+#fQO7Q
} 8DaL,bi*.
%ULr8)R;
Dv`c<+q(#
SMK_6?MZ
e\75:oQ
java代码:
X)3!_
RViuJ;
}*"p?L^p{
/*Created on 2005-7-15*/ "g8M0[7e3
package com.adt.dao.impl; X!g#T9kG
Uf+%W;}
import java.util.List; Q&bM\;Ml
]e@Oiq
import org.flyware.util.page.Page; Pk)1WK7E
-A!%*9Z
import net.sf.hibernate.HibernateException; 7Hu3>4<
import net.sf.hibernate.Query;
J5jvouR
jEJT-*I1+
import com.adt.dao.UserDAO; W
`}Rf\g
m`r(p"
/** 3=ymm^
* @author Joa VY\&8n}e(
*/ SasJic2M
public class UserDAOImpl extends BaseDAOHibernateImpl R{T$[$6S
Xla~Yg
implements UserDAO { 65^9
_:27]K:
/* (non-Javadoc) x-3\Ls[I
* @see com.adt.dao.UserDAO#getUserByName !%0 *z
o{[YA}xc
(java.lang.String) IPo?:1x]s
*/ :9 ^*
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publicList getUserByName(String name)throws kMd.h[X~
Q]>.b%s[
HibernateException { 1&Z