Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 *Nb#W!
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Ka!I`Yf
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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 6=_~0PcY
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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 x[_=#8~.1x
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分页支持类: JtKp(k&
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java代码: >pyj]y^3
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package com.javaeye.common.util; z`Wt%tL(
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import java.util.List; .1 )RW5|c
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publicclass PaginationSupport { d[gl]tj9
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publicfinalstaticint PAGESIZE = 30; Pz_Oe,{.I
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privateint pageSize = PAGESIZE; K-vWa2
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privateList items; /hW d/H]
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privateint totalCount; <Q< AwP
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privateint[] indexes = newint[0]; RSfM]w}Hq#
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privateint startIndex = 0; q(o/yx{bm
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public PaginationSupport(List items, int 's?Ai2=#
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totalCount){ }alj[)
setPageSize(PAGESIZE); cc=gCE
setTotalCount(totalCount); ZM#=`k9
setItems(items); fG LG$b
setStartIndex(0); or*HC&c7
} GV|9H]_,I
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public PaginationSupport(List items, int 5MTgK=c
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totalCount, int startIndex){ n`Z"rwKmNw
setPageSize(PAGESIZE); gT+Bhr
setTotalCount(totalCount); K<sC F[
setItems(items); MhEw
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setStartIndex(startIndex); mdih-u(T|
} m4w')r~
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public PaginationSupport(List items, int q0mOG^
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totalCount, int pageSize, int startIndex){ 2C^B_FUg|]
setPageSize(pageSize); [U
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setTotalCount(totalCount); OKOu`Hz@
setItems(items); e;YW6}'}
setStartIndex(startIndex); Yj(4&&Q
} l]!9$
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publicList getItems(){ ^4Am
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return items; *ZSdl0e
} 6R UrF
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publicvoid setItems(List items){ {i~8 :
this.items = items; SjEAuRDvUz
} "VxWj}+]
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publicint getPageSize(){ F51.N{'
return pageSize; V,v[y\
} Px@/Q
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publicvoid setPageSize(int pageSize){ <3X7T6_:@
this.pageSize = pageSize; &<'n^n
} ~|Y>:M+0Z
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publicint getTotalCount(){ 1n*W2:,z
return totalCount; '(&%O8Yi
} KGHq rc
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publicvoid setTotalCount(int totalCount){ .3 pbuU
if(totalCount > 0){ -ZOBAG*
this.totalCount = totalCount; lG<hlYckv
int count = totalCount / E
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cp
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pageSize; ,38Eq`5&W
if(totalCount % pageSize > 0) HG>j5
count++; @R~5-m
indexes = newint[count]; &Bb<4R
for(int i = 0; i < count; i++){ F9q8SA#"
indexes = pageSize * ~vdkFc(8B
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i; 6$ Q,Y}j
} }f>H\iJe
}else{ c8 K3.&P6
this.totalCount = 0; donw(_=
} bEuaOBc
} vm23U^VJ
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publicint[] getIndexes(){ (LAXM
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return indexes; XkKC!
} G`=r^$.3WB
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publicvoid setIndexes(int[] indexes){ -5G)?J/*
this.indexes = indexes; eHg3}b2r
} C"T1MTB
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publicint getStartIndex(){ :q##fG'm/
return startIndex; Pj#'}ru!
} 5wt TP ;P
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publicvoid setStartIndex(int startIndex){ ?@6b>='!
if(totalCount <= 0) eKZ%2|+j!7
this.startIndex = 0; o;F" {RZ
elseif(startIndex >= totalCount) +m\|e{G
this.startIndex = indexes
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[indexes.length - 1]; 3M*Bwt;F_
elseif(startIndex < 0) `xS{0P{uj
this.startIndex = 0; Doze8pn
else{ ?0*8RK
this.startIndex = indexes "L"150Ih
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[startIndex / pageSize]; =(AtfW^H
} {C*\O)Gep
} {-zMHVw=}
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publicint getNextIndex(){ )(Iy<Y?#
int nextIndex = getStartIndex() + vy@rQC %9
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pageSize; '$|UwT`s
if(nextIndex >= totalCount) T0HuqJty
return getStartIndex(); _K2?YY(#>
else lEL78l.
return nextIndex; Tq<2`*Qs
} 3-s}6<0v1
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publicint getPreviousIndex(){ Z*{]
,
int previousIndex = getStartIndex() - 5@osnf?
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pageSize; H!e 3~+)
if(previousIndex < 0) K2_Qu't0$
return0; &Jc_Fc(M
else 1tzV8(7
return previousIndex; X##1!
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} W><Zn=G4)b
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} %u{W7
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抽象业务类 z~6y+
java代码: &tR(n$M@>
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/** _Yb_D/
* Created on 2005-7-12 .uo.N
*/
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package com.javaeye.common.business; #1'\.v
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import java.io.Serializable; !{,F~i9
import java.util.List; 2U
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import org.hibernate.Criteria; [a[/_Sf{
import org.hibernate.HibernateException; Z]w#vLR
import org.hibernate.Session; SM 0M%
import org.hibernate.criterion.DetachedCriteria; \h<BDk*
import org.hibernate.criterion.Projections; l|`9:H
import 1&=0Wg0ig
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org.springframework.orm.hibernate3.HibernateCallback; }S-DB#6
import N<|$h5isq
}!#gu3
org.springframework.orm.hibernate3.support.HibernateDaoS |iFVh$N
| aQ"3d
upport; X8eJ4%
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import com.javaeye.common.util.PaginationSupport; Ey{%XR+*;
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public abstract class AbstractManager extends !33#. @[
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HibernateDaoSupport { UAF<m1
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privateboolean cacheQueries = false; X#a`K]!B
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privateString queryCacheRegion; /76 1o\Q
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publicvoid setCacheQueries(boolean C8N{l:1f]
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cacheQueries){ x Ha=3n
this.cacheQueries = cacheQueries; _zxLwU1(x
} PHg48Y"Nd
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publicvoid setQueryCacheRegion(String >C WKH~
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queryCacheRegion){ XALI<ZY
this.queryCacheRegion = s}&bJ"!Z
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queryCacheRegion; ?i\B^uB
} :R6bq!
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publicvoid save(finalObject entity){ $h9='0Wi0'
getHibernateTemplate().save(entity); Uv_N x10
} 7z6b@$,
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publicvoid persist(finalObject entity){ z9
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getHibernateTemplate().save(entity); /il@`w;G
} WE}kTq
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publicvoid update(finalObject entity){ $$i.O}
getHibernateTemplate().update(entity); AEmNHO@%q
} z><5R|Gf
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publicvoid delete(finalObject entity){ <q)4la
getHibernateTemplate().delete(entity); mAgF73,3
} V{-AP=C7
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publicObject load(finalClass entity, _s,ao'/
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finalSerializable id){ &MmU
return getHibernateTemplate().load
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(entity, id); MOn,Db$
} ;:S&F
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publicObject get(finalClass entity, foF19_2 ,
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finalSerializable id){ }F6<w{|
return getHibernateTemplate().get {>3\N0e5
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(entity, id); ubMOD<
} QR?yG+VU
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publicList findAll(finalClass entity){ .@)mxC:\K9
return getHibernateTemplate().find("from v7
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" + entity.getName()); :6 J +%(f
} vgIpj3u
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publicList findByNamedQuery(finalString R9We/FhOY
u*S=[dq
namedQuery){ P`4]-5gE
return getHibernateTemplate .%BT,$1K
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().findByNamedQuery(namedQuery); )"(] Lf's
} uhH^>z
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publicList findByNamedQuery(finalString query, s1Ok|31|
!{et8F@d|
finalObject parameter){ KAA-G2%M
return getHibernateTemplate /StTb,
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().findByNamedQuery(query, parameter); 'XQ`g CF=
} mpC`Yk
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publicList findByNamedQuery(finalString query, .9*wY0:
0l*]L`]L#
finalObject[] parameters){ UEs7''6RM
return getHibernateTemplate 5la>a}+!!h
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().findByNamedQuery(query, parameters); +[@z(N-h
} rVvR!"//yH
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publicList find(finalString query){ d4:`@*
return getHibernateTemplate().find 8*SDiZ
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(query); CHd9l]Rbe
} UsGa
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publicList find(finalString query, finalObject 8bK|:B#6,
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parameter){ C`=p+2I]
return getHibernateTemplate().find HD,xY4q&N
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(query, parameter); #1c]PX
} !IU.a90V
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public PaginationSupport findPageByCriteria n8=5-7UT
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(final DetachedCriteria detachedCriteria){ H>Q%"|
return findPageByCriteria ;Mm7n12z C
~ *:F{
(detachedCriteria, PaginationSupport.PAGESIZE, 0); R_]{2~J+
} AT2v!mNyCw
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public PaginationSupport findPageByCriteria h'J|K^na
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(final DetachedCriteria detachedCriteria, finalint f-6vLX\Vu
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startIndex){ v}@xlB=
return findPageByCriteria GWsE;
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(detachedCriteria, PaginationSupport.PAGESIZE, J{ [n?/A{
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startIndex); Er/bO
} i|
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public PaginationSupport findPageByCriteria A,su;Qh
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(final DetachedCriteria detachedCriteria, finalint #QCphhG
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pageSize, AE: Z+rM*
finalint startIndex){ 0![
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return(PaginationSupport) *"9><lJ-!
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getHibernateTemplate().execute(new HibernateCallback(){ ly% F."v
publicObject doInHibernate "G>3QL+O|
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(Session session)throws HibernateException { gOgps:
Criteria criteria = 8x`.26p
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detachedCriteria.getExecutableCriteria(session); '65LKD
int totalCount = &DqE{bBd!
/TS=7J#
((Integer) criteria.setProjection(Projections.rowCount =U|N=/y#hJ
(SSRY 9
()).uniqueResult()).intValue(); aA7=q=
criteria.setProjection imQURC
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(null); 3+>G#W~
List items = L@=3dp!\Cu
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criteria.setFirstResult(startIndex).setMaxResults f7Ul(D:j\
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(pageSize).list(); **69rN
PaginationSupport ps = :akT 'q#
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new PaginationSupport(items, totalCount, pageSize, FP[!BUOf"
&A#~)i5gF
startIndex); MX@IHc
return ps; @FdSFQ/9
} f#ri'&}c
:
}, true); $mF_,|
} ;?C#IU
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public List findAllByCriteria(final 8* Jw0mSw
)M2F4[vcb
DetachedCriteria detachedCriteria){ x8GJY~:SW
return(List) getHibernateTemplate oyo(1>
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().execute(new HibernateCallback(){ Z{'i F
publicObject doInHibernate \.M*lqI
){jla,[
(Session session)throws HibernateException { ">?vir^
Criteria criteria = )O:0]=#))
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detachedCriteria.getExecutableCriteria(session); 6q
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return criteria.list(); <w3!!+oK"
} hy|b6wF&
}, true); A!^q
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} !!Z?[rj
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public int getCountByCriteria(final g+X}c/".
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DetachedCriteria detachedCriteria){ F5S@I;
Integer count = (Integer) }@.|?2b +
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getHibernateTemplate().execute(new HibernateCallback(){ !ct4;.2
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publicObject doInHibernate ON+J>$[[
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(Session session)throws HibernateException { hB{jUP)";
Criteria criteria = ! VjFW5'{
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detachedCriteria.getExecutableCriteria(session); G@j0rnn>B
return ,AT[@
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criteria.setProjection(Projections.rowCount =-p$jXVW%
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()).uniqueResult(); I!^O)4QRx
} QY= = GfHt
}, true); 1'?4m0W1
return count.intValue(); `p+Zz"/
} o.I6ulY8
} 1^gl}^|B
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用户在web层构造查询条件detachedCriteria,和可选的 {T].]7Z
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 0wS+++n$5
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PaginationSupport的实例ps。 y|wc,n%L>
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ps.getItems()得到已分页好的结果集 3do)Vg4
ps.getIndexes()得到分页索引的数组 ,i@X'<;y
ps.getTotalCount()得到总结果数 itMg|%B%
ps.getStartIndex()当前分页索引 ({o'd=nO
ps.getNextIndex()下一页索引 5 (A5Y-B
ps.getPreviousIndex()上一页索引 JfPD}w
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 jmeRrnC}
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 I|Gp$uq _
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一下代码重构了。 A<ynIs<
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我把原本我的做法也提供出来供大家讨论吧: {26ONa#i
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首先,为了实现分页查询,我封装了一个Page类: IH"6? 9nd
java代码: nl9P,
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/*Created on 2005-4-14*/ $.bBFWk
package org.flyware.util.page; +sJrllrE(
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/** =)7s $
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* @author Joa SV(]9^nW
* 9VbOQ {8
*/ &
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publicclass Page { x|vqNZ\F
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/** imply if the page has previous page */ FJd]D[h
privateboolean hasPrePage; ^I+)o1%F
J4\ qEO
/** imply if the page has next page */ 1</kTm/Qa
privateboolean hasNextPage; LlSZr)X
iya"ky~H
/** the number of every page */ _l1NKk
privateint everyPage; @62Mk},9 c
&
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/** the total page number */ ~^cMys |'
privateint totalPage; |ely|U. Tf
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/** the number of current page */ &>Vfa
privateint currentPage; nak Yn
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/** the begin index of the records by the current 2r ZxSg
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query */ 3Gip<\$v
privateint beginIndex; b2FO$Os
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/** The default constructor */ vz!s~cAt
public Page(){ 2J;kSh1,L
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} *H|M;G
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/** construct the page by everyPage +="e]Yh;
* @param everyPage tq|hPd<C
* */ ?pzaG{
public Page(int everyPage){ /QJ?bD#a
this.everyPage = everyPage; $O5UyKI
} WH\))y-
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/** The whole constructor */ k Zq!&
public Page(boolean hasPrePage, boolean hasNextPage, QMpoa5ZQG
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int everyPage, int totalPage, GbaEgA'fa
int currentPage, int beginIndex){ a 7,C>%I
this.hasPrePage = hasPrePage; <(-hx+^
this.hasNextPage = hasNextPage; mOlI#5H
this.everyPage = everyPage; PKzyV ;
this.totalPage = totalPage; ~Onoe $A[<
this.currentPage = currentPage; +PuPO9jKO@
this.beginIndex = beginIndex; W}]%X4<#rN
} -Zz$~$
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/** I2nhqJy^
* @return +o51x'Ld*
* Returns the beginIndex. =%BZ9,l
*/ 5kz)5,KjM
publicint getBeginIndex(){ = MOj|NR [
return beginIndex; HF.^ysI
} u5%7}<nNi
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/** 9,r rQQD_
* @param beginIndex {7/0< NG
* The beginIndex to set. .?Gd'Lp
*/ [ra_ 2R
publicvoid setBeginIndex(int beginIndex){ mFZ?hOyP.
this.beginIndex = beginIndex; _}En/V_
} [n$BRk|
}I2@%tt?
/** n;T7= 1_"
* @return AlIpsJ[UU
* Returns the currentPage. a0ObBe'
*/ y7i*s^ys{
publicint getCurrentPage(){ IDG}ZlG
return currentPage; n0e1k.A
} HZf/CE9T
}-sdov<<
/** hBX!iukT|{
* @param currentPage 5)MS~ii
* The currentPage to set. >M/V oV
*/ ZXuv CI
publicvoid setCurrentPage(int currentPage){ 9BuSN*4
this.currentPage = currentPage; &@yo;kB
} Q{lpKe0
oT>(V]*5
/** =^5Alba/
* @return :d#VE-e
* Returns the everyPage. la+[bm<v
*/ UaB @
publicint getEveryPage(){ iB& 4>+N+
return everyPage; !GNBDRr
} x"
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)(384@'"u
/** <U\B!fO'
* @param everyPage HEM9E&rL
* The everyPage to set. A"rfZ`
*/ jmFz51
publicvoid setEveryPage(int everyPage){ lH6OcD:kj
this.everyPage = everyPage; uvG]1m#
} rMhB9zB1
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/** Ls] g
* @return Q{5kxw1ZF
* Returns the hasNextPage. J\M>33zu
*/ n*{sTT
publicboolean getHasNextPage(){ j+,d^!
return hasNextPage; (j3xAA
} x}"uZ$g
vz7J-CH
/** D,k"PaLP
* @param hasNextPage :dQ B R
* The hasNextPage to set. ZP\-T*)l$
*/ <yH4HY
publicvoid setHasNextPage(boolean hasNextPage){ [.uG5%fa
this.hasNextPage = hasNextPage; 428>BQA
} B2'i7Ps
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/** 7OJ'){R$
* @return `6]%P(#a
* Returns the hasPrePage. ?1K#dC52#
*/ =t H:,SH
publicboolean getHasPrePage(){ k@3Q|na
return hasPrePage; ei[j1F
} < F.hZGss7
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/** zZ` _D|<m
* @param hasPrePage <BMXCk
* The hasPrePage to set. %~E ?Z!_W
*/ Ke2ccN
publicvoid setHasPrePage(boolean hasPrePage){ &N\jG373
this.hasPrePage = hasPrePage; G'ei/Me6{
} B=^)Ub5'
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/** m0;CH/D0
* @return Returns the totalPage. rFj-kojg
* <#u=[_H
*/ ='s(|
publicint getTotalPage(){ U$WxHYo
return totalPage; q$B>|y U
} ZOeQ+j)|I
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/** 5',8 ziJQ
* @param totalPage v{ 0=
* The totalPage to set. z4jR[x,
*/ JSCZ{vJ$
publicvoid setTotalPage(int totalPage){ rPLm5ni
this.totalPage = totalPage; eOs)_?}
} +~mA}psr
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} W"}M1o
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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 j/f?"VEr
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个PageUtil,负责对Page对象进行构造: QD:{U8YbF$
java代码: ]v]qChZHd
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/*Created on 2005-4-14*/ ;U.hxh;+
package org.flyware.util.page; |yQZt/*SOZ
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import org.apache.commons.logging.Log; e%@~MQ-
import org.apache.commons.logging.LogFactory; b`~p.c%(
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/** V@cM |(
* @author Joa iw8yb;|z;A
* N343qU
*/ B&[M7i
publicclass PageUtil { GzI yP(U
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privatestaticfinal Log logger = LogFactory.getLog U |Jo{(Y
x,|hU@h
(PageUtil.class); -bT)]gA2
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/** X[PZg{
* Use the origin page to create a new page qB0E_y)a
* @param page $o0iLFIX/
* @param totalRecords Jrti
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* @return Sjyoc<Uo
*/ $RIecv<e_
publicstatic Page createPage(Page page, int rvbLyv;~
ktFhc3);!
totalRecords){ $JJrSwR<h
return createPage(page.getEveryPage(), mpuq 9)6
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page.getCurrentPage(), totalRecords); gv)P]{%^
} PT=2@kH
cDFO; Dr
/** VEqS;~[
* the basic page utils not including exception [y'f|XN
w$z}r
handler #\.,? A}9
* @param everyPage GqaDL3Niqs
* @param currentPage aB{vFTD5
* @param totalRecords :Q $K<)[
* @return page (e!0]Io@
*/ C":32_q
publicstatic Page createPage(int everyPage, int g`vny )\7/
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currentPage, int totalRecords){ 4'`{H@]tb
everyPage = getEveryPage(everyPage); E*V`":efS
currentPage = getCurrentPage(currentPage); TZ(cu>
int beginIndex = getBeginIndex(everyPage, ![YX]+jqNp
dZ rAn
currentPage); %C~1^9uq
int totalPage = getTotalPage(everyPage, KxYwJ
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totalRecords); ;V*R*R
boolean hasNextPage = hasNextPage(currentPage, Pe3@d|-,MU
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totalPage); -:2$ %
boolean hasPrePage = hasPrePage(currentPage); :km61
Oiz ,w7LRh
returnnew Page(hasPrePage, hasNextPage, =j5MFX.-o
everyPage, totalPage, ,2j&ko1
currentPage, TcjEcMw,
?s\:hNNY
beginIndex); ~$:|VHl
} TUV&vz{
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aM4%
privatestaticint getEveryPage(int everyPage){ 5][Ztx
return everyPage == 0 ? 10 : everyPage; -+ SF
} 0B@SN)<kH
iOR_[ y,
privatestaticint getCurrentPage(int currentPage){ l6YtEHNG
return currentPage == 0 ? 1 : currentPage; U3T#6Rptl
} +$C4\$t
A+SE91m
privatestaticint getBeginIndex(int everyPage, int xy5lE+E_U
^?cz,N~
currentPage){ ;1`fC@rI
return(currentPage - 1) * everyPage; {QcLu"?c
} {sihus#Q
UDL!43K
privatestaticint getTotalPage(int everyPage, int R:e<W/P"
YQ+tDZY8`
totalRecords){ \>jLRb|7Ts
int totalPage = 0; y.e^h RKb
ORyE`h
if(totalRecords % everyPage == 0) BSYzC9h`
totalPage = totalRecords / everyPage; lD^]\;?
else Cdas P9"1
totalPage = totalRecords / everyPage + 1 ; 6+.uU[x@
mef<=5t
return totalPage; GN ]cDik
} o.w\l\
:=/85\P0SU
privatestaticboolean hasPrePage(int currentPage){ Bt>}rYz1
return currentPage == 1 ? false : true; ]+|~cRQ9I
} Ge-CY
yaah*1ip[
privatestaticboolean hasNextPage(int currentPage, xC*6vH]?
o7J
int totalPage){ Bg&i63XL$$
return currentPage == totalPage || totalPage == l)Pu2!Ic
[s"O mAy4
0 ? false : true; <KE 1f7c
} YVYu:}e3)
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} ofPHmh`
{Or;
g .onTFwN
X9p.gXF
3Mxp)uG/
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。 N}pw74=1
:n0vQ5a
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 qQA}Z*(m
*+j*{>E
做法如下: q#vQv5
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 =+U `-J}g
:p]'32FA!
的信息,和一个结果集List: 2_n7=&
java代码: o*DN4oa)
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/*Created on 2005-6-13*/ :uWw8`
package com.adt.bo; l^|UCgRn
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import java.util.List; \hBG<nH{0
|?qquD 4=
import org.flyware.util.page.Page; PV9pa/`@
Pa{%\dsv
/** RRRCS]y7$t
* @author Joa t?}zdI(4
*/ Y( 3Bp\6
publicclass Result { 9cf:pXMi
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private Page page; '+osf'&
A%`[mc]4#
private List content; 9[G[$c
f!s=(H;
/** x$1]M DAGb
* The default constructor i'9vL:3
*/ Pa~)"u8
public Result(){ k Mu8"Az
super(); 2Ou[u#H
} l-SAC3qhG
rW+ =,L
/** BReJ!|{m}
* The constructor using fields @xbQ Ye%J
* .Nw=[
* @param page g=;%
* @param content ~ ip,Nl
*/ ^c&L,!_)H
public Result(Page page, List content){ $lLz3YS
this.page = page; Zy o[(`y
this.content = content; c17_2 @N
} 95YL]3V
)xbHCoU,
/** +n#V[~~8AI
* @return Returns the content. i(iXD
*/ l y(>8F
publicList getContent(){ w,h`s.AN
return content; OU8Lldt
} SzjkI+-$:
R~)\3] "2m
/** jg.QRny^
* @return Returns the page. '=Rs/EDME
*/ .Yf:[`Q6g
public Page getPage(){ 1UE6 4Kl:S
return page; f6p-s
y>
} %d?cP}V
[/Rf\T(,jn
/** #wV8X`g
* @param content {buo^kgj`]
* The content to set. CitDm1DXt/
*/ CC L
public void setContent(List content){ M7@2^G]p
this.content = content; ^R# E:3e
} K2J\awX
J[4mLU
/** w]]8dz
* @param page h"_MA_]~
* The page to set. bI:zp!-.
*/ xO&eRy?%
publicvoid setPage(Page page){ PK0%g$0
this.page = page; *XT/KxLa7
} y#q?A,C@n
} eD*A)
K%^V?NP*{Z
#MRMNL@
{&\jW!&n
T[j#M+p
2. 编写业务逻辑接口,并实现它(UserManager, A1.7O
iZM+JqfU|D
UserManagerImpl) vTJ}8
java代码: X22[tqg;&
v
8$>rwB
=y0C1LD+
/*Created on 2005-7-15*/ Jo@|"cE=
package com.adt.service; 4:r!|PJn{G
>_|O1H./4
import net.sf.hibernate.HibernateException; uf&myV7
oxz OA
import org.flyware.util.page.Page; A^)?Wt%*
bdQ_?S(
import com.adt.bo.Result; {TX]\ufG
0@H|n^Md#
/** L#+q]j+
* @author Joa xwJH(_-
*/ X@K-^8
publicinterface UserManager { |MFF7z{%
K':K{ee>
public Result listUser(Page page)throws ]
:BX!<
fjs
[f'L
HibernateException; r[lF<2&*R
aC%m- m
} gx\&_)w N
PYM(Xz$
il:$sd
h-Fn?
(`sH3&Kl
java代码: rdJ d#S
}M3fmAP}
d5D$&5Ec
/*Created on 2005-7-15*/ kH]yl
2
package com.adt.service.impl; %we u 1f
;9#Z@]p
import java.util.List; YwZ
Z{+n
,!7 H]4Qx
import net.sf.hibernate.HibernateException; ,'p2v)p^4
rzh#CnL3
import org.flyware.util.page.Page; PzA|t;*
import org.flyware.util.page.PageUtil; L"{JRbh[
;K!]4tfJ
import com.adt.bo.Result; #ZYVc|sT+
import com.adt.dao.UserDAO; W!6qqi{
import com.adt.exception.ObjectNotFoundException; 2ioQb`=
import com.adt.service.UserManager; 8;Yx<woR
QrYpZZ;
/** lJE93rXU
* @author Joa \hM|(*DL
*/ ,0hA'cp
publicclass UserManagerImpl implements UserManager { V{^!BBQ
jC7&s$>Q"g
private UserDAO userDAO; Kd=%tNp
Y@b.sMg{
/** ~wJFa'2
* @param userDAO The userDAO to set. TW[_Ko86
*/ =
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publicvoid setUserDAO(UserDAO userDAO){ O }(VlR2
this.userDAO = userDAO; 2UFv9
} /4vG3
)*,5"CO
/* (non-Javadoc) /Rg*~Ers
*
* @see com.adt.service.UserManager#listUser .8P.)%
Er+nk`UR_
(org.flyware.util.page.Page) [BT/~6ovrZ
*/ Z| V`B `
public Result listUser(Page page)throws wyQzM6:,yX
rxy&spX
HibernateException, ObjectNotFoundException { {6~l$
int totalRecords = userDAO.getUserCount(); Um: Hrjw
if(totalRecords == 0) nSkPM5\TI
throw new ObjectNotFoundException 6Qx#%,U^ J
G=A,9@+c
("userNotExist"); aEWWFN
page = PageUtil.createPage(page, totalRecords); k&.Jk
B"
List users = userDAO.getUserByPage(page); ?_Q/}@`
returnnew Result(page, users); -*m+(7G\
} LWHd~"eU
rwG CUo6Z
} 'ul~7h;n
{WPobP"
l?Fb ='#
yRiP{$E
-tyK~aasQ
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 A _XhuQB;d
sRrzp=D
询,接下来编写UserDAO的代码: Hv\-_>}K
3. UserDAO 和 UserDAOImpl: OBP1B@|l$+
java代码: dVFf.
*
;Cy=J+
tc!wLnhG
/*Created on 2005-7-15*/ *0>mB
package com.adt.dao; y!!E\b=
CJXg@\\/
import java.util.List; ]f_6 '|5A
q7-L53.x
import org.flyware.util.page.Page; %LZ({\5K#f
e&qh9mlE
import net.sf.hibernate.HibernateException; N~NQ6:R[
v0ES;
/** aN $}?
* @author Joa IrWD%/$H
*/ L[20m(6?
publicinterface UserDAO extends BaseDAO { A%{W{UP8N
3Bx:Ntx<
publicList getUserByName(String name)throws hweaGL t0
ul ER1\W
HibernateException; &2=dNREJ}1
u*#ZXW
publicint getUserCount()throws HibernateException; wlEo"BA
`UQf2o0%3w
publicList getUserByPage(Page page)throws %bD}m!
-~QHqU.
HibernateException; Z+StB15
Xj5~%DZp
} ?x0pe4^If
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?l $Nf@-
]+m/;&0
PGARXw+
java代码: F1Hh7
F
= 07]z@s
bug
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/*Created on 2005-7-15*/ bQZ*r{g
package com.adt.dao.impl; l?q%?v8
}h}<!s
import java.util.List; yj$TPe_BW
BkZV!Eg
import org.flyware.util.page.Page; $\"9<o|h
ee/&/Gt
import net.sf.hibernate.HibernateException; 3w!c`;c%
import net.sf.hibernate.Query; f(eQ+0D
,=
&B28Qe)
import com.adt.dao.UserDAO; 7lo|dg80
D>!6,m2
/** N7s'6(`=X
* @author Joa `+/H^
*/ :Yj)CGl$
public class UserDAOImpl extends BaseDAOHibernateImpl C P3<1~
^o !O)D-q
implements UserDAO { `:eViVl6e
IjfxR mV
/* (non-Javadoc) }elH75[64
* @see com.adt.dao.UserDAO#getUserByName R <"6ojn
4"vaMa
(java.lang.String) &|<xqt
*/ =9LC<2
publicList getUserByName(String name)throws PjIeZ&p
YOAn4]j
HibernateException { 3},Zlu
String querySentence = "FROM user in class 2Nj9U#A
h)v^q: ='
com.adt.po.User WHERE user.name=:name"; M-
0i7%
Query query = getSession().createQuery ]p~IYNl2%j
Q8MS,7y/
(querySentence); (Bo bB]~a
query.setParameter("name", name); 60Z]M+8y8
return query.list(); ntP|\E
} 8)VgS&B~
w#^U45y1v
/* (non-Javadoc) ba3-t;S
* @see com.adt.dao.UserDAO#getUserCount() &l