Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 #XqCz>Z
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 eYlI };
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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 =)g}$r
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 4]p#9`j
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分页支持类: jC}HNiM78
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java代码: |=,jom
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package com.javaeye.common.util; 6`7bk35B
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import java.util.List; wWf_d jd
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publicclass PaginationSupport { ?Y8hy|`
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publicfinalstaticint PAGESIZE = 30; oyk&]'>
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privateint pageSize = PAGESIZE; :wg=H
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privateList items; Qhc;Zl
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privateint totalCount; (^g XO
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privateint[] indexes = newint[0]; X2%(=B
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privateint startIndex = 0; W+"^! p|
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public PaginationSupport(List items, int YtWw)IK
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totalCount){ I''n1v?N
setPageSize(PAGESIZE); ,1Z([R*
setTotalCount(totalCount); 8c9<kGm$E
setItems(items); aL90:,V
setStartIndex(0); M,li\)J!&
} &s?uMWR
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public PaginationSupport(List items, int [ @"6:tTU
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totalCount, int startIndex){ L'aB/5_%
setPageSize(PAGESIZE); NR
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setTotalCount(totalCount); `]6<j<'
,
setItems(items); e`7>QS;.
setStartIndex(startIndex); L1(-xNUo_i
} U{pg
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public PaginationSupport(List items, int z;<~j=lP
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totalCount, int pageSize, int startIndex){ U{[YCs fk
setPageSize(pageSize); vZ srlHb
setTotalCount(totalCount); {}Is&^3Z
setItems(items); aD'Ax\-
setStartIndex(startIndex); CX\XaM)l
} aL+>XN
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publicList getItems(){ M
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return items; Y(kf<Wo
} >.K%W*t
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publicvoid setItems(List items){ iZeq
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this.items = items; W,CAg7:*
} #\D74$D
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publicint getPageSize(){ ZOa| lB (,
return pageSize; LK}FI*A_
} vo*oCfm
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publicvoid setPageSize(int pageSize){ BU??}{
this.pageSize = pageSize; s>L.V2!$0
} 7t<MHdw
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publicint getTotalCount(){ eh]syeKBj
return totalCount; .lP',hn
} 5<v1v&
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publicvoid setTotalCount(int totalCount){ q
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if(totalCount > 0){ ;l @lA)i
this.totalCount = totalCount; ivq(eKy
int count = totalCount / 6z6\xkr
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pageSize; #(Gz?kGAH`
if(totalCount % pageSize > 0) *xsBFCRU
count++; $^{#hYq)o
indexes = newint[count]; ]|,}hsN
for(int i = 0; i < count; i++){ rEj[XK
indexes = pageSize * "uIaKb
c};%VB
i; Fc \]*
} FE,mUpHIR
}else{ ?jlz:Z4
this.totalCount = 0; E JuTv%Y8
} <y^_&9
} @/^mFqr2
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publicint[] getIndexes(){ _[Imwu}
return indexes; m=^]93+
} $,, PF/N8c
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publicvoid setIndexes(int[] indexes){ Bh cp=#
this.indexes = indexes; ZnI15bsDx
} Q]N&^ E
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publicint getStartIndex(){ [{u3g4`}
return startIndex; v7./u4S|V
} LFHJj-nk
t4v'X}7q]
publicvoid setStartIndex(int startIndex){ Q#SQ@oUzD
if(totalCount <= 0) $>O~7Nfst7
this.startIndex = 0; !1=OaOT
elseif(startIndex >= totalCount) !f52JQyh
this.startIndex = indexes 2 Kjd!~Z$
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[indexes.length - 1]; breF,d$
elseif(startIndex < 0) ^ `Ozw^~
this.startIndex = 0; t&{;6MiE
else{ fpo{`;&F
this.startIndex = indexes 7(.Z8AO
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[startIndex / pageSize]; 8/dMvAB1So
} eU%49 A
} _Wg}#r
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publicint getNextIndex(){ OmBz'sp:
int nextIndex = getStartIndex() +
-NN=(p!<
*{fs{gFw9
pageSize; b6f OHy
if(nextIndex >= totalCount) |w{Qwf!2
return getStartIndex(); MAFdJ+n#
else ,7)hrA$(
return nextIndex; Yn="vpM1
} j`RG Moq
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publicint getPreviousIndex(){ 0,ryy,2
int previousIndex = getStartIndex() - =ejU(1 g
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pageSize; Ri" hU/H{
if(previousIndex < 0) |JYb4J4Ni
return0; LiT%d
else A2M(
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return previousIndex; d8jH?P-"
} -9= DDoO
ySO\9#Ho
} 9c)#j&2?H
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抽象业务类 /CsP@f_Gw
java代码: zQY ,}a
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/** 3jxC}xz)
* Created on 2005-7-12 g3NUw/]#
*/ %w65)BFQ
package com.javaeye.common.business; L>sLb(2\i
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import java.io.Serializable; !mUJ["#
import java.util.List; ^)>( <6
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import org.hibernate.Criteria; r4*H96l
import org.hibernate.HibernateException; `K.B`
import org.hibernate.Session; (Fzy8
s
import org.hibernate.criterion.DetachedCriteria; C'$}{%Cc@$
import org.hibernate.criterion.Projections; 'A:Y&w"r
import :\"0jQ.y|
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org.springframework.orm.hibernate3.HibernateCallback; 2\1+M)
import /y-D_
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org.springframework.orm.hibernate3.support.HibernateDaoS lgU!D |v
cHF W"g78
upport; )>FAtE
~-7/9$ay5
import com.javaeye.common.util.PaginationSupport; Ex
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public abstract class AbstractManager extends =exCpW>
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HibernateDaoSupport { uKk#V6t#
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{
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privateboolean cacheQueries = false; F:ycV~bE
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privateString queryCacheRegion; :gwmk9LZ
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publicvoid setCacheQueries(boolean ?tjEXg>ny
z U[pn)pe
cacheQueries){ (rBsh6@)
this.cacheQueries = cacheQueries; Zio!j%G
} cl^UFlf[
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publicvoid setQueryCacheRegion(String %@a;q?/?Nd
,ZJ}X 9$<
queryCacheRegion){ BNdq=|,+"
this.queryCacheRegion = jJiuq#;T3
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queryCacheRegion; qco'neR"z
} # atq7tX
Ly2,*\7
publicvoid save(finalObject entity){ Y0,{fw<
getHibernateTemplate().save(entity); 3?FY?Q[
} $mM"C+dD
nb/q!8
publicvoid persist(finalObject entity){ #0<pRDXj
getHibernateTemplate().save(entity); 2PSExK57
} j
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publicvoid update(finalObject entity){ WS n>P7sY
getHibernateTemplate().update(entity); YM_ [
} cwzkA,e@
n>.@@
publicvoid delete(finalObject entity){ h8UhrD<:
getHibernateTemplate().delete(entity); u/j\pDl.
} ]}g\te
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publicObject load(finalClass entity, uZn_*_J!
j_90iP^5:
finalSerializable id){ Fw&ImRMk
return getHibernateTemplate().load PdO"e
jV*10kM<
(entity, id); [IOI&`?D
} y{mt *VA4
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publicObject get(finalClass entity, &qXobJRM
)b1hF
finalSerializable id){ QHO n?e
return getHibernateTemplate().get t!rrYBSCr
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(entity, id); E6~VHQa2?
} q&@s/k
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publicList findAll(finalClass entity){ xFp$JN
return getHibernateTemplate().find("from zy$jTqDH
^x O](,H
" + entity.getName()); Y[7prjd
} H[KX xNYZ_
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publicList findByNamedQuery(finalString fphCQO^#vW
xW)
namedQuery){ _=I1
return getHibernateTemplate s&nat4{B
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().findByNamedQuery(namedQuery); H1U$ApD
} bQ3<>e\%B
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publicList findByNamedQuery(finalString query, j$Ndq(<tG
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finalObject parameter){ HQ"T>xb
return getHibernateTemplate 'm*W<
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().findByNamedQuery(query, parameter); 2EM6k|l5
} [G8EX3
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publicList findByNamedQuery(finalString query, Ox J0."
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finalObject[] parameters){ "W+>?u )
return getHibernateTemplate `$jun
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().findByNamedQuery(query, parameters); hev;M)t
} iqB5h|
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publicList find(finalString query){ o
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return getHibernateTemplate().find )e0kr46
BmpAH}%T
(query); "v?F4&\ 8
} o7E|wS
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publicList find(finalString query, finalObject #:BkDidt2v
(Nc~l ^a
parameter){ Vc5>I_
return getHibernateTemplate().find ^*f D
+:^l|6%}
(query, parameter); |1CX?8)b=
} nyPeN?-
rVP\F{Q4Tr
public PaginationSupport findPageByCriteria 0e0)1;t\
jA9uB.I,"b
(final DetachedCriteria detachedCriteria){ AcuZ?LYzK
return findPageByCriteria ,(q]
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E'4Psx9: =
(detachedCriteria, PaginationSupport.PAGESIZE, 0); OcV,pJ
} eef&ZL6g
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public PaginationSupport findPageByCriteria =_BHpgL
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(final DetachedCriteria detachedCriteria, finalint X>`03?L
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startIndex){ QBGm)h?=
return findPageByCriteria _Vp"G)1Y
*y?6m,38V
(detachedCriteria, PaginationSupport.PAGESIZE, 0^S$_L
AH n!>w,
startIndex); (y;
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} zB0*KgAn{
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public PaginationSupport findPageByCriteria G?@W;o)
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(final DetachedCriteria detachedCriteria, finalint }&/>v' G
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pageSize, d@ 8M_
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finalint startIndex){ :AlvWf$d
return(PaginationSupport) m2^vH+wD
s?;8h &]=
getHibernateTemplate().execute(new HibernateCallback(){ 5FJLDT2Lg
publicObject doInHibernate yfV]f
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(Session session)throws HibernateException { "9'3mmZm=?
Criteria criteria = N{bg-%s10i
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detachedCriteria.getExecutableCriteria(session); 8<}=f4vUj5
int totalCount = AJ6l#j-
swZi
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((Integer) criteria.setProjection(Projections.rowCount >ymn&_zlT
v3cMPN
()).uniqueResult()).intValue(); KwHN c\\
criteria.setProjection kCD]&
n[e C
(null); ynM:]*~K
List items = ./;uhj
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criteria.setFirstResult(startIndex).setMaxResults W8bp3JX"
F8<G9#%s\
(pageSize).list(); %J2Ad
PaginationSupport ps = b?OA |JqX
>k`qPpf&
new PaginationSupport(items, totalCount, pageSize, ,Tar?&C:
\&+Y;:6
startIndex); ]@Y!,bw&
return ps; A^M]vk%dg
} bvh#Q_
}, true); }v}F8}4
} hfI=9x/
zZPWE"u}
public List findAllByCriteria(final 6bUP]^d
0,~s0]h0V
DetachedCriteria detachedCriteria){ sAU%:W{
return(List) getHibernateTemplate &'i_A%V
[- 92]
().execute(new HibernateCallback(){ 3.#L
publicObject doInHibernate 4+>yL+sC%v
bP-(N14x+
(Session session)throws HibernateException { 75p9_)>96
Criteria criteria = _!zc <&~I
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detachedCriteria.getExecutableCriteria(session); 2;T?ry7
return criteria.list(); WqefH{PB
} Uf+y$n-
}, true); TYD( 6N
} !m:WoQ/
#!z-)[S.+
public int getCountByCriteria(final e0y.J
y "+'4:_
DetachedCriteria detachedCriteria){ cO{NiRIb
Integer count = (Integer) >
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%[KnpJ{\
getHibernateTemplate().execute(new HibernateCallback(){ nI?*[y}
publicObject doInHibernate @d{}M)6\!
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(Session session)throws HibernateException { r4[=pfe25
Criteria criteria = Tv7W)?3h
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detachedCriteria.getExecutableCriteria(session); BMO,eQcB
return jt}oq%Bf
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criteria.setProjection(Projections.rowCount VtzZ1/JE
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()).uniqueResult(); aWimg6q
} |-vyhr0
}, true); 'fK=;mM
return count.intValue(); 1J1Jp|j.
} *A!M0TK?i,
} A4(L47^
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用户在web层构造查询条件detachedCriteria,和可选的 0^Ldw)C"
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 i#YDdz
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PaginationSupport的实例ps。 ;DX{+Z[
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ps.getItems()得到已分页好的结果集 !lzj.|7=1
ps.getIndexes()得到分页索引的数组 "24d:vf\
ps.getTotalCount()得到总结果数 6[XaIco=C
ps.getStartIndex()当前分页索引 {BM:c$3@j
ps.getNextIndex()下一页索引 ApSseBhh
ps.getPreviousIndex()上一页索引 P\WHM(
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 bny@AP(CY+
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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 0e"KdsA:<U
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一下代码重构了。 bZWR.</
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我把原本我的做法也提供出来供大家讨论吧: X)]>E]X
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首先,为了实现分页查询,我封装了一个Page类: ?xKiN5q"6
java代码: O<!^^7/h0
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/*Created on 2005-4-14*/ g- #eMQ%J
package org.flyware.util.page; QP<P,Bi~
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/** :FSg%IUX
* @author Joa :W&klUU"
* GPAC0K^p
*/ vr47PM2al
publicclass Page { (.oDxs()I
FLPN#1
/** imply if the page has previous page */ gjT`<CW
privateboolean hasPrePage; 056yhB
}1CO>a<
/** imply if the page has next page */ >Gg[J=7`
privateboolean hasNextPage; aAoAjV NkK
;/m>c{
/** the number of every page */ WR.7%U';
privateint everyPage; Zq1> M'V;
gDfM} 2]/
/** the total page number */ ,9=P=JH
privateint totalPage; =fBr2%qK
,t1s#*j\!q
/** the number of current page */ +A,cdi9z
privateint currentPage; z&GGa`T"
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/** the begin index of the records by the current m|cRj{xZF
jvd3_L-@E<
query */ 0~<t :q!
privateint beginIndex; VasQ/
cv_O2Q4,@
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/** The default constructor */ ioTqT:.
public Page(){ <0`"vPU
QQHC
1
} 6*ZZ)W<
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/** construct the page by everyPage :i?c
* @param everyPage Qw%0<~<
* */ Z#%77!3
public Page(int everyPage){ )Knsy
this.everyPage = everyPage; qj*BV
} /e*<-a
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/** The whole constructor */ f}FJR6VO
public Page(boolean hasPrePage, boolean hasNextPage, R<h0RKiM@
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NVC$8imip
int everyPage, int totalPage, )[sSCt]
int currentPage, int beginIndex){ #@5 jOi
this.hasPrePage = hasPrePage; CA"`7<,
this.hasNextPage = hasNextPage; n |,}
this.everyPage = everyPage; wAb_fU&*
this.totalPage = totalPage; y7*^H
this.currentPage = currentPage; BYS>"
this.beginIndex = beginIndex; 9*|An
} NX+
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/** gY=+G6;=<
* @return 6d 8n1_
* Returns the beginIndex. N)z]
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*/ Q([g1?F9*
publicint getBeginIndex(){ v#IZSBvuQK
return beginIndex; oU 8o;zk0
} HoM8V"8B
VxAR,a1+n
/** JY>I
* @param beginIndex wIbc8ze
* The beginIndex to set. uoBPi[nK
*/ ,%m$_wA$
publicvoid setBeginIndex(int beginIndex){ gD fVY%[Z
this.beginIndex = beginIndex; pm;g)p?
} 7@VR:~n}k
GHWpL\A{8`
/** M9S[{Jj*
* @return `V0]t_*D
* Returns the currentPage. -3b0;L&4>x
*/ lu.2ZQE
publicint getCurrentPage(){ Ki@8
return currentPage; C[$<7Mi|;
} l}c<eEfOy"
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/** C{S6Ri
* @param currentPage N=L
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* The currentPage to set. }mJ)gK5b 6
*/ B "}GAk}V
publicvoid setCurrentPage(int currentPage){ I`KN8ll
this.currentPage = currentPage; 9p$q@Bc
} `^N;%[c`z
J5rR?[i{
/** WCWBvw4&"{
* @return _H3cqD
* Returns the everyPage. N4mQN90t
*/ 'XQv> J
publicint getEveryPage(){ A><%"9pZ
return everyPage; +Q_Gm3^
} L_Ai/'
Ri-wbYFaP
/** z?YGE iR/}
* @param everyPage T
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* The everyPage to set. "|&*MjwN6
*/ J<zg 'Jk^
publicvoid setEveryPage(int everyPage){ 4Y/!V[
this.everyPage = everyPage; q{JD]A :
} ZyWC_r!
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/** Hm^p^,}_x
* @return {S&&X&A`v
* Returns the hasNextPage. mg;AcAS.o,
*/ +yea}uUE
publicboolean getHasNextPage(){ Rx<pV_|H,
return hasNextPage; XKK*RVs#
} <(t<gS #
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/** Cw2+@7?|
* @param hasNextPage n*xNMw1x"T
* The hasNextPage to set. aY+>85?g
*/ LtvyWc`
publicvoid setHasNextPage(boolean hasNextPage){ ) D`_V.,W
this.hasNextPage = hasNextPage; |Z/ySAFM
} &boBu^,94
q.X-2jjpx:
/** (6+0U1[Iz
* @return Ek.j@79
* Returns the hasPrePage. RGKJO_*J2
*/ +[7u>RJ
publicboolean getHasPrePage(){ K^vMIo h
return hasPrePage; z'I0UB#
} tw')2UGg
MdfkC6P
/** 6a!X`%N=
* @param hasPrePage
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* The hasPrePage to set. 0\o'd\
*/ *Ee# x!O
publicvoid setHasPrePage(boolean hasPrePage){ %qv7;E2C
this.hasPrePage = hasPrePage; 87/{\h
} g/yXPzLU
cK } Qu
/** vNt2s)J$
* @return Returns the totalPage. = @f;s<v/
* A|+{x4s`
*/ 8YJ({ Ou_
publicint getTotalPage(){ Y#5S;?bR
return totalPage; ]_,~q@r$
} *]=)mM#
BW;u?1Xa
/** _B[(/wY
* @param totalPage yiU dUw/
* The totalPage to set. uQNoIy J)
*/ dA~6{*)
publicvoid setTotalPage(int totalPage){ h 2zCX
this.totalPage = totalPage; sOW|TN>y\
} J.d `tiN
mB~&nDU
} PrcM'Q
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/P%:u0fX,
>JMKEHl.q
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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 I|:j~EY
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个PageUtil,负责对Page对象进行构造: @mazwr{B
java代码: -wt2ydzos
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/*Created on 2005-4-14*/ ublY!Af
package org.flyware.util.page; YGO@X(ej,
A.FI] K@
import org.apache.commons.logging.Log; o5R\7}]GE
import org.apache.commons.logging.LogFactory; 6M9rC[h\
H6eGLg={
/** #Grm-W9E
* @author Joa L5W>in5(
* $9~1s/('
*/ @:@rks&
publicclass PageUtil { `4qKQJw
GSH{1VS_b
privatestaticfinal Log logger = LogFactory.getLog >A/=eW/q
(r4\dp&
(PageUtil.class); dw|0K+-PH
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/** J Nz0!wi
* Use the origin page to create a new page
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* @param page P.:T
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* @param totalRecords 6>I.*Qt \l
* @return URgF8?n
*/ QFYy$T+W
publicstatic Page createPage(Page page, int a6d KQ3D
I'C,'
totalRecords){ qg/5m;U
return createPage(page.getEveryPage(), gib]#n1!p
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page.getCurrentPage(), totalRecords); 2cg z
n@
} ,Mc2dhq
Mm!saKT%
/** 8E+l;2
* the basic page utils not including exception 8rYK~Sz
%-Z~f~<?
handler w$4Lu"N:
* @param everyPage O|~'-^
* @param currentPage xJhbGK
* @param totalRecords `,Gk1~Wv
* @return page [
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*/ )QD}R36Ic
publicstatic Page createPage(int everyPage, int `9l\~t(M
$ Zr,-
currentPage, int totalRecords){ ise}> A!t
everyPage = getEveryPage(everyPage); z<>_*Lfj
currentPage = getCurrentPage(currentPage); ^@2Vh*k
int beginIndex = getBeginIndex(everyPage, vNbA/sM
mtHz6+
currentPage); $@)d9u
cd
int totalPage = getTotalPage(everyPage, HV.7IyBA^
X;:xGZ-oY
totalRecords); +kL(lBv'
boolean hasNextPage = hasNextPage(currentPage, dk/*%a
+
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totalPage); 1`{ib
boolean hasPrePage = hasPrePage(currentPage); Pa +BE[z
,m,vo_Ub
returnnew Page(hasPrePage, hasNextPage, (xed(uFEK
everyPage, totalPage, +.I'U9QeUN
currentPage, $4L3y
uH
{6sfa?1j
beginIndex); ~*Qpv&y)
} m9@n
17oxD
privatestaticint getEveryPage(int everyPage){ ($>0&w
return everyPage == 0 ? 10 : everyPage; ;7k7/f:
} >>zoG3H!
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privatestaticint getCurrentPage(int currentPage){ dAl<'~g
return currentPage == 0 ? 1 : currentPage; Zd ,=
} V bOLTc
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privatestaticint getBeginIndex(int everyPage, int +hgCk87%#
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currentPage){ Ai18]QD-
return(currentPage - 1) * everyPage; u$8MVP
} Cl!jK^AbG
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privatestaticint getTotalPage(int everyPage, int ZF(=^.gc
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totalRecords){ UE w3AO
int totalPage = 0; T9-a
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if(totalRecords % everyPage == 0) bU`yymf{L
totalPage = totalRecords / everyPage; {+9\o ~
else MPN=K|*
totalPage = totalRecords / everyPage + 1 ; d/rz0L
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return totalPage; $]J IA|
} Eo&qc 17)`
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privatestaticboolean hasPrePage(int currentPage){
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return currentPage == 1 ? false : true; $ n[7
} :-" jKw
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privatestaticboolean hasNextPage(int currentPage, MWh+h7k'
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int totalPage){ _C=[bI@
return currentPage == totalPage || totalPage == >0#q!H,X
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0 ? false : true; ^l&4UnLlc
} ky$:C,1t
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} _kX/LR"L+
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+\vY; !^
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上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 M;V#Gm
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面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 M`pTT5r
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做法如下: Prz+kPP
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 :k(t/*Nl3
iiB )/~!O
的信息,和一个结果集List: lY9M<8g
java代码: N%|Vzc
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/*Created on 2005-6-13*/ _XNR um4
package com.adt.bo; <sYw%9V
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import java.util.List; / !
0*/ r'
import org.flyware.util.page.Page; !_H8Q}a
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/** f<4q ]HCa
* @author Joa )X!DCL:16
*/ | 4oM+n;Y
publicclass Result {
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private Page page; 8421-c6y>
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private List content; bW.zxQ:
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/** I+j|'=M
* The default constructor _6S
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*/ >c\v&k>6.
public Result(){ )F#<)Evw
super(); :Z]hI+7
} ~7 L)n
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/** r]O@HVbt$
* The constructor using fields {e[pSD6
* AH87UkNL
* @param page = *;Xc-_
* @param content w$[Ds
*/ |U$de2LF
public Result(Page page, List content){ ecqz@*d&
this.page = page; HZ<f(
this.content = content; ~muIi#4
} g6/N\[b%
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/** Z0 IxYEp
* @return Returns the content. 8xpYQ<cax
*/ ,{ L;B
publicList getContent(){ f'`nx;@X
return content; Re,$<9V
} s!;VUr\
pg}+lYGP
/** .UhBvHH
* @return Returns the page. ZDkD%SCy
*/ 1QF*e'
public Page getPage(){ .m]=JC5'
return page; m`\i+
} PVS<QN%
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/** V3A>Ag+^~
* @param content /$Tl#
* The content to set. Rp`_Grcd
*/ +`s&i%{1>
public void setContent(List content){ h6T/0YhWLP
this.content = content; ['OCw {<
} 1S[5#ewB;j
^'u;e(AaE
/** t3#H@0<
* @param page 'f?&EsIV?
* The page to set. eFj6p<
*/ _z(5e
publicvoid setPage(Page page){ Ad`[Rt']kI
this.page = page; B`?N0t%X
} rv%ye
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} x#j\"$dla
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2. 编写业务逻辑接口,并实现它(UserManager, w^dueP7J
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UserManagerImpl) Q{l*62Bx
java代码: v<7Gln
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/*Created on 2005-7-15*/ #[U9(44,
package com.adt.service; fr'huvc
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import net.sf.hibernate.HibernateException; -wfRR>)d
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import org.flyware.util.page.Page; `Ge +(1x
jqX@&}3@
import com.adt.bo.Result; >Z2,^5P{
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/** H7yg9zFT
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* @author Joa D-o7yc"K
*/ b,rH&+2H
publicinterface UserManager { 2i7i\?<.
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public Result listUser(Page page)throws <nb3~z1
$p0 /6c
HibernateException; DD@)z0W
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} S}m$,<x
1(%>`=R8
@Ge>i5q
oxMUW<gYd
}#ep}h
java代码: #j^('K|
>9.5-5"
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/*Created on 2005-7-15*/ 0j{F^rph
package com.adt.service.impl;
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import java.util.List; mZbWRqP[|_
cZDxsd]
import net.sf.hibernate.HibernateException; 9RCO|J
%R.xS}
Q
import org.flyware.util.page.Page; @ kJ0K
import org.flyware.util.page.PageUtil; w*<Y$hnBzF
[:nx);\
import com.adt.bo.Result; >k&8el6h
import com.adt.dao.UserDAO; Q$|^~
import com.adt.exception.ObjectNotFoundException; R,x> $n
import com.adt.service.UserManager; GP[6nw_'^
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/** Ue{vg$5||
* @author Joa 2/yXY_L
*/ e$Xq
publicclass UserManagerImpl implements UserManager { C5PmLiOHY>
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private UserDAO userDAO; |RR%bQ^{
*%T)\\H2
/** I #M%%5e
* @param userDAO The userDAO to set. "K|)<6J
*/ k'[ S@+5
publicvoid setUserDAO(UserDAO userDAO){ * MSBjH|
this.userDAO = userDAO; 0^GbpSW{
} ;m@1Ec@*p
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/* (non-Javadoc) fg9?3x
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* @see com.adt.service.UserManager#listUser xH_A@hf;
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(org.flyware.util.page.Page) =zeFK_S!
*/ %6NO 0 F^
public Result listUser(Page page)throws .
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2E`~ qn
HibernateException, ObjectNotFoundException { U,Z"G1^
int totalRecords = userDAO.getUserCount(); hWq.#e6
if(totalRecords == 0) j>0<#SYBu
throw new ObjectNotFoundException ?w+ QbT
QP6z?j.
("userNotExist"); 4GG1E. z}
page = PageUtil.createPage(page, totalRecords); SXRdNPXFO
List users = userDAO.getUserByPage(page); <91t`&aWW
returnnew Result(page, users); *2JH_Cj`
} o {=qC: b
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} eecw]P_?
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s<A*[
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 hq/J6 M
)t|^Nuj8
询,接下来编写UserDAO的代码: iD>G!\&