Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Y_tLSOD#/
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ^ ]02)cK
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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 l?2(c
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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 ()a(PvEO
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。 <ZGEmQ
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分页支持类: "uf*?m3
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java代码: pESlBQ7{I
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package com.javaeye.common.util; &D0suK#
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import java.util.List; ,WSK
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publicclass PaginationSupport { 8|*#r[x
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publicfinalstaticint PAGESIZE = 30; k`FCyO
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privateint pageSize = PAGESIZE; QFt7L
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privateList items; z(V?pHv+
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privateint totalCount; =%P'?(o|
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privateint[] indexes = newint[0]; AT Dm$ *
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privateint startIndex = 0; E`s9SE
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public PaginationSupport(List items, int GPlAQk
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totalCount){ OjO$.ecT
setPageSize(PAGESIZE); hd{Vz{;W
setTotalCount(totalCount); ?|!167/O
setItems(items); /^ *GoB
setStartIndex(0); 3 d
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} W _j`'WN/
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public PaginationSupport(List items, int 7oaa)
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totalCount, int startIndex){ uis;S)+
setPageSize(PAGESIZE); Pl^-]~
setTotalCount(totalCount); i\hH .7G1
setItems(items); BM PLL2I
setStartIndex(startIndex); cfI5KLG~#
} NCbl|v=
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public PaginationSupport(List items, int )P4#P2
Vfew )]I
totalCount, int pageSize, int startIndex){ @gzm4
setPageSize(pageSize); `s74g0h
setTotalCount(totalCount); kB_u U !G
setItems(items); ]=ar&1}J
setStartIndex(startIndex); 5"(AqXoq
} t95hI DtD
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publicList getItems(){ *4}lV8
return items; S~^0
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} &X0/7)*"v
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publicvoid setItems(List items){ V"":_`1VW
this.items = items; V#
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} LX A1rgUWT
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publicint getPageSize(){ LL3RC6;e
return pageSize; G#n99X@-
} `L0aQ$'>z
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publicvoid setPageSize(int pageSize){ <jdS0YT
this.pageSize = pageSize; &We1i&w
} u*_I7.}9
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publicint getTotalCount(){ - bL
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return totalCount; +o&E)S}wP
} VU,\OOp
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publicvoid setTotalCount(int totalCount){ [{3WHS.
if(totalCount > 0){ <()xO(
this.totalCount = totalCount; $$C5Q;7w!
int count = totalCount /
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pageSize; .&2p Z
if(totalCount % pageSize > 0) +kCVi
count++; W"9iFj X
indexes = newint[count]; N{n}]Js1D-
for(int i = 0; i < count; i++){ 6_/oVvd
indexes = pageSize * #sit8k`GR8
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i; zSta!]
} pNpj, H*4
}else{ k f~71G+
this.totalCount = 0; 6w{^S~rqo
} 2,|*KN*e`W
} 9R.IYnq
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publicint[] getIndexes(){ wqo2iRql
return indexes; 9/C0DDb
} j}YZl@dYV
@(.?e<
publicvoid setIndexes(int[] indexes){ -F,o@5W>Y
this.indexes = indexes; U,/NygB~
} R`=IYnoOA
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publicint getStartIndex(){ p-V#nPb
return startIndex; D[{p~x^
} AEkgm^t.{
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publicvoid setStartIndex(int startIndex){ S8j;oJ2d
if(totalCount <= 0) Y1AbG1n|
this.startIndex = 0; EK.L>3
elseif(startIndex >= totalCount) }]sI?&xB
this.startIndex = indexes ,u QLXF2
*|AnL}GJ
[indexes.length - 1]; 6Nx T W
elseif(startIndex < 0) bTC2Ya
this.startIndex = 0; QQ@, v@j5
else{ BXueOvO8
this.startIndex = indexes A`u04Lm7
v}dt**l
[startIndex / pageSize]; THQW8 V
} oMda)5 &
} yAEOn/.~
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publicint getNextIndex(){ j-$aa;
int nextIndex = getStartIndex() + >rlQY>5pH
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pageSize; `g%]z@'+?
if(nextIndex >= totalCount) !$h%$se
return getStartIndex(); 18w[T=7)
else Zx25H"5j
return nextIndex; Faa:h#
} Fy-nV%P
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publicint getPreviousIndex(){ x@.iDP@(
int previousIndex = getStartIndex() - qM@][]j:
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pageSize; IC[SJVH;
if(previousIndex < 0) !_<. 6ja
return0; `{I,!to
else .^#{rk
return previousIndex; ` 2|~Z
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} hX)r%v:
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} /0SG
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抽象业务类 t,N-|
java代码: .5L/<
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/** &m8B%9w
* Created on 2005-7-12 cv:nlq)
*/ 3~I<f^K4
package com.javaeye.common.business; e^~t52]
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import java.io.Serializable; ~QBf78@Gf
import java.util.List; $';'MoS
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import org.hibernate.Criteria; l@1f L%f
import org.hibernate.HibernateException; sLbz@5 4
import org.hibernate.Session; toTAWT D
import org.hibernate.criterion.DetachedCriteria; /dOQ4VA\
import org.hibernate.criterion.Projections; =i%2/kdi0b
import PyYKeo=
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\A
org.springframework.orm.hibernate3.HibernateCallback; T<zonx1
import cdU2ph_
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org.springframework.orm.hibernate3.support.HibernateDaoS nq/xD;q
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upport; AG}'
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import com.javaeye.common.util.PaginationSupport; [$[t.m
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public abstract class AbstractManager extends >;xEzc!W3*
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HibernateDaoSupport { +*0THol-
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privateboolean cacheQueries = false; }WI24|`zM
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privateString queryCacheRegion; n^&QOII@>
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publicvoid setCacheQueries(boolean *kyy''r
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cacheQueries){ qwFn(pK[
this.cacheQueries = cacheQueries; m$LZ3=v%8
} W\~ZmA.
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publicvoid setQueryCacheRegion(String T>f-b3dk
)STt3.
queryCacheRegion){ _%zU^aE
this.queryCacheRegion = k})9(Sy~
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queryCacheRegion; {##A|{$3%
} HwST^\Ao
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publicvoid save(finalObject entity){ D@
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getHibernateTemplate().save(entity); vMRKs#&8
} 2DV{gF
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publicvoid persist(finalObject entity){ ) ]~HjA;
getHibernateTemplate().save(entity); %< j=&
} kI[EG<N1k
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publicvoid update(finalObject entity){ }_?7k0EZ@
getHibernateTemplate().update(entity); BMX x(W]
} &OzJ^G\o
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publicvoid delete(finalObject entity){ :cynZab
getHibernateTemplate().delete(entity); '!1lK
} p$9N}}/c
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publicObject load(finalClass entity, K4RjGSaF
;( 2uQ#Y
finalSerializable id){ q"52-42
return getHibernateTemplate().load ;=^WIC+Nr
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(entity, id); q0c)pxD%`
} i;dr(c/ft
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publicObject get(finalClass entity, =~EQ3uX
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finalSerializable id){ t]&n_]`{.
return getHibernateTemplate().get ^9{ 2
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(entity, id); lJYv2EZ
} \uPT-M*
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publicList findAll(finalClass entity){ 3t_5Xacj
return getHibernateTemplate().find("from X*Q7Yu
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" + entity.getName()); }Ql;% 7
} Ahwu'mgnC
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publicList findByNamedQuery(finalString A6U6SvM;
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namedQuery){ ?b7vc^E&
return getHibernateTemplate gTQ6B,`/8
Xs?>6i@$$
().findByNamedQuery(namedQuery); ftH
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} [X=eCHB?
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publicList findByNamedQuery(finalString query, :iWV:0)P
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finalObject parameter){ vcSS+
return getHibernateTemplate TX+t
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().findByNamedQuery(query, parameter); }}xR?+4A
} -OW$
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publicList findByNamedQuery(finalString query, D0]9
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finalObject[] parameters){ p_nrua?
return getHibernateTemplate #]'V#[;~
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;
().findByNamedQuery(query, parameters); M1>a,va8Zq
} "bO]
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publicList find(finalString query){ JH5])i0
return getHibernateTemplate().find 6x7=0}'
u}h'v&"e,
(query); x-QP+M`Pu
} >L(F{c:
g ` {0I[
publicList find(finalString query, finalObject }9kq?
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parameter){ ejQCMG7
return getHibernateTemplate().find wb?hfe
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(query, parameter); | UaI i^
} Q6>vF)(
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public PaginationSupport findPageByCriteria IpP0|:}
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(final DetachedCriteria detachedCriteria){ bpILiC
return findPageByCriteria N?Z?g_a8
!6%mt} h
(detachedCriteria, PaginationSupport.PAGESIZE, 0); %In"Kh*
} h=tY 5]8
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public PaginationSupport findPageByCriteria /6fPC;l
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(final DetachedCriteria detachedCriteria, finalint ;wF|.^_2
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startIndex){ $5o<Mj
return findPageByCriteria /l`XJs
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(detachedCriteria, PaginationSupport.PAGESIZE, |q>Mw-=
r6)1Y`K=9
startIndex); n"
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} pWp2{G^XB
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public PaginationSupport findPageByCriteria K|/a]I":
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(final DetachedCriteria detachedCriteria, finalint izw}25SW
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pageSize, `iI"rlc
finalint startIndex){ nXS%>1o,
return(PaginationSupport) 525 >=h
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getHibernateTemplate().execute(new HibernateCallback(){ KWUz]>Z
publicObject doInHibernate 0_EF7`T
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(Session session)throws HibernateException { xRUYJ=|oh
Criteria criteria = @rMW_7[y
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detachedCriteria.getExecutableCriteria(session); #jJcgR<
int totalCount = YMd&+J`
?Sqm`)\>4
((Integer) criteria.setProjection(Projections.rowCount 85
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jJvNN -^
()).uniqueResult()).intValue(); Y Pc<
criteria.setProjection 8iN As#s
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(null); -(.7/G'Vk>
List items = 57>ne)51
_ XZ=4s
criteria.setFirstResult(startIndex).setMaxResults h"ylpv+
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(pageSize).list(); <&2,G5XA
PaginationSupport ps = =1VH5pVr}
m { fQL
new PaginationSupport(items, totalCount, pageSize, ar|[D7Xrq\
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startIndex); dWy1=UQfP
return ps; Z]f2&
} x,dv~QU
}, true); q@9i3*q;
} mmL~`i/
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public List findAllByCriteria(final 5m42Bqy"
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DetachedCriteria detachedCriteria){ G{.+D2
return(List) getHibernateTemplate HH?*"cKF~
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().execute(new HibernateCallback(){ O:)IRB3
publicObject doInHibernate ~S6 {VK.
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(Session session)throws HibernateException { ~P_kr'o
Criteria criteria = ]Qr8 wa>Z
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detachedCriteria.getExecutableCriteria(session); LDeVNVM
return criteria.list(); GJs[m~`8#
} c!Vc_@V,
}, true); J36@Pf]h
} L@r.R_*H?s
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public int getCountByCriteria(final Xb*_LZAU
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DetachedCriteria detachedCriteria){ M[u3]dN
Integer count = (Integer) 4d
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getHibernateTemplate().execute(new HibernateCallback(){ ZPao*2xz
publicObject doInHibernate MPn>&28"|K
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(Session session)throws HibernateException { i(;-n_:,`
Criteria criteria = G3+a+=e
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detachedCriteria.getExecutableCriteria(session); %k
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return "v!HKnDT
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criteria.setProjection(Projections.rowCount m1i+{((
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()).uniqueResult(); [9om"'
} /'6[*]IZP
}, true); 9Fx z!-9m
return count.intValue(); hX%v`8
} /kU@S
} gsWlTI
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用户在web层构造查询条件detachedCriteria,和可选的 l0\>zWLZZ9
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ?{,)XFck
14 'x-w^~k
PaginationSupport的实例ps。 o!r4 frP
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ps.getItems()得到已分页好的结果集 !9 LAXM
ps.getIndexes()得到分页索引的数组 Y~hd<8 ~
ps.getTotalCount()得到总结果数 -^Km}9g
ps.getStartIndex()当前分页索引 `AHNk7 t=
ps.getNextIndex()下一页索引 5zw23!
ps.getPreviousIndex()上一页索引 )|R0_9CLV
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N vHy'
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 soQzIx
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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 7W firRM
9Q7cUoxY
一下代码重构了。 `[ ` *@O(y
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我把原本我的做法也提供出来供大家讨论吧: FJ,\?ooGf
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首先,为了实现分页查询,我封装了一个Page类: f9XO9N,hE:
java代码: \
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/*Created on 2005-4-14*/ ^=Tu>{uD
package org.flyware.util.page; h8= MVh(I
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/** C\2 >7
* @author Joa UFAMbI
* hPi
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*/ 0R 5^p
publicclass Page { *o\Y~U-so
dms:i)L2
/** imply if the page has previous page */ zV(tvt
privateboolean hasPrePage; i~Ob( YIH
2N8sq(LK{
/** imply if the page has next page */ ^@LhUs>3
privateboolean hasNextPage; )tI2?YIR
JvWs/AG1
/** the number of every page */ {S"
privateint everyPage; 2\CkX
q'AnI$!
/** the total page number */ M=
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privateint totalPage; 2:HP5
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/** the number of current page */ 7- 3N
privateint currentPage; ocA'goI-
I1 R\Ts@
/** the begin index of the records by the current ])ALAAIc-
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query */ {L-aXe{
privateint beginIndex; a(43]d&
i_'R"ob{S
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/** The default constructor */ p5# P
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public Page(){ UFIAgNKl
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} Jn@Mbl
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/** construct the page by everyPage 0@e}hv;
* @param everyPage {Fp`l\,
* */ s8yTK2v2\
public Page(int everyPage){ PxVI{:Uz
this.everyPage = everyPage; CMxjX
} qfP"UAc{/
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/** The whole constructor */ 7k#${,k
public Page(boolean hasPrePage, boolean hasNextPage, Dss/>!
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int everyPage, int totalPage, ND55`KT4
int currentPage, int beginIndex){ o
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this.hasPrePage = hasPrePage; N4` 9TN7
this.hasNextPage = hasNextPage; &(uF&-PwO4
this.everyPage = everyPage; o )nT
this.totalPage = totalPage; wp]7Lx?F
this.currentPage = currentPage; D_19sN@0m
this.beginIndex = beginIndex; N} x/&e
} kG;eOp16R
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/** pW3)Y5/D
* @return @a.6?.<L
* Returns the beginIndex. 3e!Yu.q:
*/ peTO-x^a-
publicint getBeginIndex(){ n"<GJ.{
return beginIndex; jQ_|z@OV
} 5nxS+`Pn.)
N9JgV,`
/** Xx y
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* @param beginIndex & L.PU@
* The beginIndex to set. _^xh1=Qr}n
*/ |p8"9jN@}c
publicvoid setBeginIndex(int beginIndex){ DtJTnvG~B
this.beginIndex = beginIndex; ++Ys9Y)*,
} 4<3?al&
i^s`6:rNu
/** ghJ,s|lH
* @return 9?l?G GmQ
* Returns the currentPage. '[=yfh
*/ X4P}aC
publicint getCurrentPage(){ UU;-q_H6
return currentPage; f?>-yMR|
} =@1R ozt
;*)fO?TG)
/** e0|_Z])D
* @param currentPage UP~WP@0F
* The currentPage to set. 1hMX(N&|
*/ =~W0 ~lxX
publicvoid setCurrentPage(int currentPage){ `r'0"V
this.currentPage = currentPage; vzohq1r5
} &`
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/** |B1;l<|`
* @return FQ_%)Ty2
* Returns the everyPage. 7i+!^Qj?y
*/ M]4 =(Vv+5
publicint getEveryPage(){ h[-d1bKwS
return everyPage; =mi:<q
} aX[1H6&=7
x'=3&vc4
/** P+;CE|J`X
* @param everyPage B.Zm$JZ:
* The everyPage to set. veX"CY`hn
*/ z*dQIC
publicvoid setEveryPage(int everyPage){ e0~sUVYf
this.everyPage = everyPage; j2o1"
} !0!U01SWa
/.| A
/** [yYH>~SuwZ
* @return :Er^"9'A2
* Returns the hasNextPage. :!+}XT7)/
*/ u^aFj%}]L
publicboolean getHasNextPage(){ n ,&/D
return hasNextPage; {XDY:`vZ}
} Uxk[O
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/** Z92iil;t
* @param hasNextPage ~|r'2V*
* The hasNextPage to set. O ':0V
*/ $TD~k;
publicvoid setHasNextPage(boolean hasNextPage){ ~$&:NB1~q
this.hasNextPage = hasNextPage; $KwI}>E4
} w PG1P'w;
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/** Uw2,o|=O
* @return |b$>68:
* Returns the hasPrePage. F}6DB*
*/ wDT>">&d
publicboolean getHasPrePage(){ N"Qg\PS_
return hasPrePage; M1/M}~
} +{")E)
<fC@KY>#
/** S'
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* @param hasPrePage @)W(q5)}9"
* The hasPrePage to set. .pS&0gBo\
*/ PcHSm/d0e
publicvoid setHasPrePage(boolean hasPrePage){ ~7lTqY\
this.hasPrePage = hasPrePage; `1E|PQbWc
} :mXGIRi
:jt;EzCLg%
/** vU_d=T%$
* @return Returns the totalPage. (~j,mk
* fBf4]^
*/ 74@lo-/LY
publicint getTotalPage(){ &v5G92
return totalPage; r/NSD$-n
} [x2JFS#4
^CZCZ,v
/** 8sN#e(@
* @param totalPage V=j-Um;
* The totalPage to set. GBH_r0
*/ K3vseor
publicvoid setTotalPage(int totalPage){ v229H<
this.totalPage = totalPage; _ztZ>'
} ,op]-CY5
g>2aIun_Q
} GVmC }>z
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fD1?z"lo
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o"rq/\ovv
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 '|vD/Qf=&
Tub1Sv>J
个PageUtil,负责对Page对象进行构造: o! aLZ3#X
java代码: [##`Um
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YBb)/ZghY
/*Created on 2005-4-14*/ #O2wyG)oU
package org.flyware.util.page; Q~Ay8L+
v,/[&ASz
import org.apache.commons.logging.Log; yXJ]U
\ %
import org.apache.commons.logging.LogFactory; J|VK P7
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/** XDPL;(?
* @author Joa :P3{Nxa
* +c^_^Z$_4o
*/ s|Z:}W?{
publicclass PageUtil { ]dvPx^`d{
,i?)
privatestaticfinal Log logger = LogFactory.getLog \7pipde
>[ eW">:>K
(PageUtil.class); ')B =|T)
>T<6fpXuk2
/** \|CPR6I
* Use the origin page to create a new page 10p8|9rE}B
* @param page yn SBVb!)
* @param totalRecords )uZoH8?
* @return #
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x
*/ C:]s;0$3'9
publicstatic Page createPage(Page page, int ,4[dLWU
4&Byl85q
totalRecords){ !c%
return createPage(page.getEveryPage(), t/}L36@+
'It?wB W
page.getCurrentPage(), totalRecords); B[r<m J
} vxZg &SRK
> 2#%$lX6
/** '"y}#h__T
* the basic page utils not including exception Yc^%zxub
-<_QF82
handler 6?N4l ]l
* @param everyPage O|QUNr9
* @param currentPage >R!"P[*
* @param totalRecords l^\(ss0~
* @return page U4BqO
:sd
*/ bmu6@jT
publicstatic Page createPage(int everyPage, int "e 1wr
*h$&0w
y
currentPage, int totalRecords){ -."kq.m*
everyPage = getEveryPage(everyPage); #ZJMlJ:q`"
currentPage = getCurrentPage(currentPage); Vtr3G.P^
int beginIndex = getBeginIndex(everyPage, Ly;I,)w
i}v9ut]B
currentPage); GcT;e5D
int totalPage = getTotalPage(everyPage, SxJ$b
l3.
totalRecords); iv*V#J>
boolean hasNextPage = hasNextPage(currentPage, .}q]`<]ze
;f:gX`"\
totalPage); ^i+[m
boolean hasPrePage = hasPrePage(currentPage); ]jyM@
@Br
{!#Wf
returnnew Page(hasPrePage, hasNextPage, u:@U
$:sZ
everyPage, totalPage, CK0l9#g
currentPage, 3X;{vO\a1
8'A72*dhX
beginIndex); >H>gH2qp
} q/NY72tj0
#EDEYEW7
privatestaticint getEveryPage(int everyPage){ 9Hd;353Q
return everyPage == 0 ? 10 : everyPage; !;S"&mcPDJ
} ?7
\\e ;j}
!^e =P%S
privatestaticint getCurrentPage(int currentPage){ 'cV?i&;
return currentPage == 0 ? 1 : currentPage; yhpz5[AuO
} rEdY>\'
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privatestaticint getBeginIndex(int everyPage, int (luKn&826
w&Y{1r F>
currentPage){ .63=(o
return(currentPage - 1) * everyPage; E V2 )
} qj!eLA-aD
WNs}sNSf
privatestaticint getTotalPage(int everyPage, int 7\ypW $Ot
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totalRecords){ hN3u@P^
int totalPage = 0; 9xFO]Y"
Pao%pA.<
if(totalRecords % everyPage == 0) KVkMU?6
totalPage = totalRecords / everyPage; $d/&k`
else (&[[46
totalPage = totalRecords / everyPage + 1 ; .m;G$X|3U
pXu/(&?
return totalPage; 2#vv$YD
} =wG+Ao
<P_ea/5:|
privatestaticboolean hasPrePage(int currentPage){ ~=En+J}*
return currentPage == 1 ? false : true; bl;zR
} Ow:1?Z{4
e$e#NoN
privatestaticboolean hasNextPage(int currentPage, ";x+1R.d
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int totalPage){ Ub_4yN;
return currentPage == totalPage || totalPage == yHeEobvb
4nqoZk^R
0 ? false : true; w8Vw1wW
} bc I']WgB-
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} kM/Te{<
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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。 R"AUSO|{
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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 C[uOReo
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做法如下: ~rD={&0
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 8X$LC
k|YWOy@D~
的信息,和一个结果集List: nV*y`.+
java代码: 9Q;c,]
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/*Created on 2005-6-13*/ j(rL
package com.adt.bo; '?QuJFki
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import java.util.List; EH*o"N`!r
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import org.flyware.util.page.Page; ,=QM#l]
b'YE9E
/** b:J(b?
* @author Joa MZ>6o5K|
*/ FLZWZ;
publicclass Result { /9pM>Cd*Z
$ ((6=39s
private Page page; (ljF{)Ml+=
])DX%$f
private List content; CO:u1?
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/** ccFn.($p?,
* The default constructor .w?(NZ2~
*/ 69K{+|
public Result(){ dXHB #
super(); \2 y5_;O
} kq=V4-a[
FQz?3w&ia
/** Kl{>jr8B3
* The constructor using fields zSEs?
* )D&M2CUw"f
* @param page 8~lIe:F-
* @param content ~ PWSo%W8
*/ xNK1h-t
public Result(Page page, List content){ i_Re*
this.page = page; /u%h8!"R
this.content = content; &MZ$j46
} Ny- [9S-<
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/** M:KbD|
* @return Returns the content. g7V8D
*/ l_'[27
publicList getContent(){ )d\j I
return content; (>4aibA'P
} :~Q!SL N
}R[#?ty;]
/** uMb>xxf
* @return Returns the page. WEg6Kz
*/ m([(:.X/IX
public Page getPage(){ oX@ya3!Pz
return page; )tHaB,
} LVJI_ O{fH
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/** b-U
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* @param content =L|tp%!
* The content to set. J_;N:7'p
*/ w%AcG~`j!B
public void setContent(List content){ KlV:L 4a~
this.content = content; C?ib_K*
} 1"7Sy3
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/** )n49lr6X
* @param page :A
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* The page to set. 5!YA o\S
*/ %CwL:.|
publicvoid setPage(Page page){ n% 'tKU\q
this.page = page; Pi,QHb`>
} 2kAx>R
} -oeL{9;
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2. 编写业务逻辑接口,并实现它(UserManager, Pg9hW
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UserManagerImpl) 'i;|c
java代码: 8.'#?]a
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/*Created on 2005-7-15*/ WwH+E]^e+
package com.adt.service; =S '%`] f?
~>O)
import net.sf.hibernate.HibernateException; 6qN~/TnHZ
S po?i.#
import org.flyware.util.page.Page; }bN%u3mHws
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import com.adt.bo.Result; .z13 =yv
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/** CK,
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* @author Joa {'16:dTJ
*/ '!f5?O+E
publicinterface UserManager { R |KD&!~Z
9&RFO$WH
public Result listUser(Page page)throws 5NJ4
hzk6rYg1
HibernateException; nQ|r"|g
r\nx=
} 0Z{j>=$
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e
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java代码: =@F&o4) r
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gWY"w!f
/*Created on 2005-7-15*/ m7T)m0
package com.adt.service.impl; h*ZC*eV>
p&VU0[LIC0
import java.util.List; \QU^>23
Xl74@wq
import net.sf.hibernate.HibernateException; Ts~L:3oaQ
RCRpzY+@
import org.flyware.util.page.Page; ja=F 7Usb
import org.flyware.util.page.PageUtil; 1~$);US
d#2$!z#
import com.adt.bo.Result; ')GSAY7
import com.adt.dao.UserDAO; .f+TZDUO
import com.adt.exception.ObjectNotFoundException; |p$spQ
import com.adt.service.UserManager; ePIiF_X
_=|vgc
/** ,^icPQSwc
* @author Joa 6"dD2WV/
*/ klUQkz |<a
publicclass UserManagerImpl implements UserManager { eW|^tH
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private UserDAO userDAO; 'U'yC2BI n
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/** 1
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* @param userDAO The userDAO to set. :kfp_o+J
*/ B:7mpSnEQ
publicvoid setUserDAO(UserDAO userDAO){ BL&LeSa
this.userDAO = userDAO; 7t.!lh5G%
} KD^N)&k^Kp
ZoArQ(YFy
/* (non-Javadoc) h;3cd0
* @see com.adt.service.UserManager#listUser 3j3N!T9
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(org.flyware.util.page.Page) r1fGJv1!o
*/ x`6<m!d`
public Result listUser(Page page)throws ]vuwkn+)
_ 84ut
HibernateException, ObjectNotFoundException { XV^1tX>f{
int totalRecords = userDAO.getUserCount(); Hty0qr3
if(totalRecords == 0) ,-z9 #t
throw new ObjectNotFoundException KF4PJi;*
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("userNotExist"); %6_AM
page = PageUtil.createPage(page, totalRecords); qTQBt}
List users = userDAO.getUserByPage(page); z3uW)GQ.
returnnew Result(page, users); yv)ux:P&+
} sN5B7)Vc
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} wb~@7,D
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6]-SK$
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ur$l Z0
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询,接下来编写UserDAO的代码: gynh#&r
3. UserDAO 和 UserDAOImpl: uIZWO.OdU
java代码: "U7qo}`I
5YrBW:_OI
}*L(;r)q
/*Created on 2005-7-15*/ E4hLtc^
+
package com.adt.dao; 5<w g8y
9*a=iL*Nw
import java.util.List; h9eMcCU
5ls6t{Ci
import org.flyware.util.page.Page; -{ZWo:,r~q
0tU.(
import net.sf.hibernate.HibernateException; QV\eMuNy
` Jdb ;
/** ~s5SZK*
* @author Joa RSo&