Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 8YI.f
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Z4#lZS`'A
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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 ,"/<N*vh
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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 gd9ZlHo'Id
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。 pf.T{/%
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分页支持类: m9^?p
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java代码: N"~P` H![x
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package com.javaeye.common.util; D_E^%Ea&`
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import java.util.List; Q"]C"?
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publicclass PaginationSupport { 5utMZ>%w_#
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publicfinalstaticint PAGESIZE = 30; E&k{ubcT
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privateint pageSize = PAGESIZE; r\+AeCyb"p
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privateList items; 8;3T65KY
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privateint totalCount; ilv6A9/
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privateint[] indexes = newint[0]; bHcb.;<
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privateint startIndex = 0; ;(3fr0cr:
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public PaginationSupport(List items, int _nRY5YnL4P
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totalCount){ 8<u_ wt@
setPageSize(PAGESIZE); ~S Js2-2
setTotalCount(totalCount); di6A.N5A
setItems(items); s#sr1[9}G
setStartIndex(0); F0Xv84:O
} .a:Oj3=0
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public PaginationSupport(List items, int {:
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totalCount, int startIndex){ Yg%V
setPageSize(PAGESIZE); 1p,G8 v+B
setTotalCount(totalCount); |::kC3=
setItems(items); (CYVSO
setStartIndex(startIndex); 6m21Y8N
} lfR"22t
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public PaginationSupport(List items, int \~nUk7.
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totalCount, int pageSize, int startIndex){ wP/rR D6
setPageSize(pageSize); &K k+RHM
setTotalCount(totalCount); ,K7C2PV6
setItems(items); \`x'r$CV
setStartIndex(startIndex); +7+
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} "/hs@4{u9
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publicList getItems(){ t]FFGnBZ
return items; +u_mT$|T
} y)U8\
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publicvoid setItems(List items){ -tx)7KV-
this.items = items; qd3B>f
} 2!dIW5I
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publicint getPageSize(){ 7 pg8kq@
return pageSize; Uy ;oJY
} I}Q3B3Byg
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publicvoid setPageSize(int pageSize){ wr*A%:
this.pageSize = pageSize; TO[5h Y\
} wSIt"g,%
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publicint getTotalCount(){ ) !ZA.sx
return totalCount; R|!4Y`
} w_eu@R:u@
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publicvoid setTotalCount(int totalCount){ 0e8)*2S
if(totalCount > 0){ m{Q{ qJ5>
this.totalCount = totalCount; 6?}8z
q[
int count = totalCount / R|NmkqTK~(
bz H5Lc {%
pageSize; 2~h)'n7Mw
if(totalCount % pageSize > 0) x)#k$QU
count++; }9P)<[>
indexes = newint[count]; U$VTk
for(int i = 0; i < count; i++){ ;?inf`t
indexes = pageSize * |c 8p{)
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i; \/K>Iv'$
} 40%p
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}else{ 9FK:lFGD
this.totalCount = 0; >1s:F5u"
} nEOhN
} >tP/"4c
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publicint[] getIndexes(){ @zfeCxVOA
return indexes; R52q6y:<x
} r(vk2Qy
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publicvoid setIndexes(int[] indexes){ O";r\Z
this.indexes = indexes; j-
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} $BH0W{S
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publicint getStartIndex(){ L/nz95
return startIndex; ;p\rgam
} L1)?5D
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publicvoid setStartIndex(int startIndex){ L ?KEe>;r
if(totalCount <= 0) E pM
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this.startIndex = 0; ,{z$M
elseif(startIndex >= totalCount) >wcsJ{I
this.startIndex = indexes k~=-o>}C
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[indexes.length - 1]; E?Q=#+}U
elseif(startIndex < 0) X[;4.imE
this.startIndex = 0; 2b|vb}|t{
else{ wZrdr4j
this.startIndex = indexes Bfw>2
P!bm$h*3?
[startIndex / pageSize]; }aX).u
} yJb;V#
} FLy|+4D_%4
, PN?_N
publicint getNextIndex(){ 103^\Av8
int nextIndex = getStartIndex() + k )){1O
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pageSize; *QLl
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if(nextIndex >= totalCount) ,rX!V=Z5
return getStartIndex(); H`@x5RjS
else miN(a; Q2P
return nextIndex; i@B5B2
} a+]=3o
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publicint getPreviousIndex(){ k,v.U8
int previousIndex = getStartIndex() - l^0
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pageSize; \D}/tz5~B
if(previousIndex < 0) c1n? @L
return0; RI*Q-n{
else 2! wz#EC
return previousIndex; 3U:0 ,-j"
} [BV{=;iD
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} Wdy2;a<\{
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抽象业务类 f$WO{J
java代码: C t SAo\F
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/** .+[[m$J
* Created on 2005-7-12 ]m}>/2oSs
*/ ;UPw;'
package com.javaeye.common.business; _&w!JzpXT
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import java.io.Serializable; <<;j=Yy({`
import java.util.List; Jge;/f!i
HVu_@[SYR3
import org.hibernate.Criteria; )0d3sJ8
import org.hibernate.HibernateException; m&ZdtB|
import org.hibernate.Session; *4(.=k
import org.hibernate.criterion.DetachedCriteria; +;>>c`{
import org.hibernate.criterion.Projections; H9jj**W ;$
import $\P!P.
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org.springframework.orm.hibernate3.HibernateCallback; J-,T^Wv
import MCYrsgg}
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org.springframework.orm.hibernate3.support.HibernateDaoS /-4%ug tD$
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upport; @ObsW!g
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import com.javaeye.common.util.PaginationSupport; 'x6Mqv1W
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public abstract class AbstractManager extends 7x1jpQ-
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HibernateDaoSupport { \<z{@
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privateboolean cacheQueries = false; {=R=\Y?r&
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privateString queryCacheRegion; \{~x<<qFd
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publicvoid setCacheQueries(boolean a{u)~:/G
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cacheQueries){ DsFrA]
this.cacheQueries = cacheQueries; =n#xnZ3
} mY%PG
@P@t/
publicvoid setQueryCacheRegion(String FNm8j#c~Q
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queryCacheRegion){ Y}Qu-fm
this.queryCacheRegion = }S42.f.p
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queryCacheRegion; +$<m ;@mZ
} *?i~AXJm
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publicvoid save(finalObject entity){ n$~RgCf
getHibernateTemplate().save(entity); _|s{G
} 2KPXRK
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publicvoid persist(finalObject entity){ &i!.6M2
getHibernateTemplate().save(entity); Mv;7kC7]
} *.~M#M 9c
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publicvoid update(finalObject entity){ $T*kpUXH}
getHibernateTemplate().update(entity); Y#rao:I
} l[h??C`
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publicvoid delete(finalObject entity){ \s)j0F)
getHibernateTemplate().delete(entity); 4ci
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} ;,IGO7R
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publicObject load(finalClass entity, HF0J>Clq
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finalSerializable id){ K@?S0KMK
return getHibernateTemplate().load Z/2#h<zj
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(entity, id); ,NVQ C=
} Z4rK$B
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publicObject get(finalClass entity, Ejn19{
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finalSerializable id){ TT29LC@
return getHibernateTemplate().get ;H}?8L
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(entity, id); :@n e29,}
} /)v X|qtIY
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publicList findAll(finalClass entity){ 3lLO.
return getHibernateTemplate().find("from ! WQEv_G@
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" + entity.getName()); hL&z"_`
} M(5l Su
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publicList findByNamedQuery(finalString g.z/%LpK
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namedQuery){ "|&SC0*
return getHibernateTemplate 5 kQC
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().findByNamedQuery(namedQuery); ?_ p3^kl
} C/lpSe
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publicList findByNamedQuery(finalString query, T}U`?s`)
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finalObject parameter){ XFH7jHnL+U
return getHibernateTemplate ,Y}HP3
%/~Sq?f-9@
().findByNamedQuery(query, parameter); &Tl3\T0D
} ;B!&( 50e
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publicList findByNamedQuery(finalString query,
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finalObject[] parameters){ WG1x:,-
return getHibernateTemplate !WAbO(l
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().findByNamedQuery(query, parameters); OBu$T&
} 'Kc;~a
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publicList find(finalString query){ \iO
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return getHibernateTemplate().find ql^n=+U
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(query); 7!z0)Ai_>=
} !~PV\DQN
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publicList find(finalString query, finalObject j#.Aiy:,
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parameter){ >~2oQ[n
return getHibernateTemplate().find 9Yd<_B#
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(query, parameter); /_>S0
} _@SC R%
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public PaginationSupport findPageByCriteria E ekX|*
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(final DetachedCriteria detachedCriteria){ 51l :
return findPageByCriteria kwWDGA?zFB
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); qy/xJ>:
} f D2.Zh
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public PaginationSupport findPageByCriteria x7> '
1
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(final DetachedCriteria detachedCriteria, finalint sYYNT*
"! m6U#^
startIndex){ $CRu?WUS]'
return findPageByCriteria l*":WzRGvF
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(detachedCriteria, PaginationSupport.PAGESIZE, d3<7t
sA#}0>`3S
startIndex); ^#KkO3
} 2old})CLJ
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public PaginationSupport findPageByCriteria ;y/&p d+
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(final DetachedCriteria detachedCriteria, finalint VMXccT9i!
-QN1=G4
pageSize, kq8.SvIb
finalint startIndex){ gwm!Pw j
return(PaginationSupport) X0.k Q
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getHibernateTemplate().execute(new HibernateCallback(){ Z8%?ej`8
publicObject doInHibernate wQEsq<
d)1 d0ES
(Session session)throws HibernateException { SFv'qDA
Criteria criteria = 3 f@@|vZF
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detachedCriteria.getExecutableCriteria(session); A+de;&
int totalCount = @>cz$##`
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((Integer) criteria.setProjection(Projections.rowCount FC@h6\+a
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()).uniqueResult()).intValue(); C.].HQ
criteria.setProjection k{d]
N:x--,2
(null); [MhKR }a
List items = +saXN6
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criteria.setFirstResult(startIndex).setMaxResults %PM&`c98z7
"ngULpb{R
(pageSize).list(); JlR$"GU
PaginationSupport ps = ( RO-~-
& %A&&XT9
new PaginationSupport(items, totalCount, pageSize, !mHMFwvS
GZH{"_$
startIndex); `Y O(C<r-
return ps; Pm&h v*D
} :e1kpQ
}, true); sPX&XqWx
} ,.9k)\/V
}C4wED.
public List findAllByCriteria(final s|IY
t^
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DetachedCriteria detachedCriteria){ 5C0![$W>
return(List) getHibernateTemplate iR?}^|]
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().execute(new HibernateCallback(){ cX7 O*5C
publicObject doInHibernate }D># AFs6#
@@JyCUd
(Session session)throws HibernateException { *:bexD H
Criteria criteria = @,Z0u2WLl6
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detachedCriteria.getExecutableCriteria(session); ls7eypKR
return criteria.list(); JTIt!E}P
} V6Mt;e)C
}, true); TZ&X0x8
} 6_,JW{#"
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public int getCountByCriteria(final Z<^;Ybw{`Z
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DetachedCriteria detachedCriteria){ FFa =/XB"
Integer count = (Integer) TZ *>MySiF
}@eIO|
getHibernateTemplate().execute(new HibernateCallback(){ :*f 2Bn
publicObject doInHibernate m/z,MT74*J
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(Session session)throws HibernateException { Nv=78O1
Criteria criteria = &1(- 8z*
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detachedCriteria.getExecutableCriteria(session); U0gZf5;*
return #u}%r{T
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criteria.setProjection(Projections.rowCount SQ_Je+X
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()).uniqueResult(); fIl;qGz85
} WQ{[q" O
}, true); wA\5-C7j
return count.intValue(); z/u^
} 8Qo'[+4;
} 6<EGH*GQ$
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用户在web层构造查询条件detachedCriteria,和可选的 (`S^6-^
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 m8ts!6C
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PaginationSupport的实例ps。 s3HVX'
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ps.getItems()得到已分页好的结果集 Wl |5EY
ps.getIndexes()得到分页索引的数组 As< B8e]
ps.getTotalCount()得到总结果数 +x(#e'6p
ps.getStartIndex()当前分页索引 R*:>h8
ps.getNextIndex()下一页索引 V:$+$"|
ps.getPreviousIndex()上一页索引 RN[I%^$"
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 @^xtxtjzux
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 %8,$ILN
,;_+o]
一下代码重构了。 0^lWy+
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我把原本我的做法也提供出来供大家讨论吧: L.Qz29\
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首先,为了实现分页查询,我封装了一个Page类: I |U'@E
java代码: .E<nQWz8
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/*Created on 2005-4-14*/ @eJCr)#}
package org.flyware.util.page; N7?B"p/
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/** x;17}KV
* @author Joa q0iJy@?A
* .!x&d4;,q
*/ KNUK]i&L
publicclass Page { m[^lu1\wn
qOwql(vX
/** imply if the page has previous page */ /'+>/
privateboolean hasPrePage; j{@6y
EU$.{C_O(
/** imply if the page has next page */ Ks-$:~?5":
privateboolean hasNextPage; j,.\QwpU
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/** the number of every page */ Ax;=Zh<DAv
privateint everyPage; 1z?}'&:
l4>^79* *
/** the total page number */ {'5"i?>s0>
privateint totalPage; O`B,mgT(
<h/%jM>9/
/** the number of current page */ {~3QBMx6
privateint currentPage; `7CK;NeT
[d: u(
/** the begin index of the records by the current Cf
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query */ *'?7OL
privateint beginIndex;
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/** The default constructor */ !sb r!Qt
public Page(){ UFG_ZoD+
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} Ao\xse{E
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/** construct the page by everyPage kAki9a(=!
* @param everyPage D|N4X`T`
* */
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public Page(int everyPage){ SIe!=F[
this.everyPage = everyPage; an"&'D}U
} 2
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/** The whole constructor */ TSlB.pw%v
public Page(boolean hasPrePage, boolean hasNextPage, #Wk=y?sn
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@^P^-B
int everyPage, int totalPage, 5(3O/C{?~
int currentPage, int beginIndex){ "& ,ov#
this.hasPrePage = hasPrePage; IS2cU'
this.hasNextPage = hasNextPage; hH %>
this.everyPage = everyPage; p+VU:%.t
this.totalPage = totalPage; .ZpOYhk
this.currentPage = currentPage; i%hCV o
this.beginIndex = beginIndex; .%zcm
} =V^-@ji)b
l8\UO<^fY
/** \|]mClj#
* @return C=:<[_m`
* Returns the beginIndex. VdLoi\-/L
*/ H@Dpht>[
publicint getBeginIndex(){ "Ms;sdjg}&
return beginIndex; x:|Y)Dn\
} $x0SWJ \G
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/** YX\vk/[|
* @param beginIndex J|`0GDSn
* The beginIndex to set. #b/qR^2qW
*/ '7Gv_G_
publicvoid setBeginIndex(int beginIndex){ h051Ol\v*
this.beginIndex = beginIndex; I;(3)^QH#
} at: li
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/** #z\ub5um
* @return D|]BFu)F
* Returns the currentPage. H_+n_r*
*/ dftBD
publicint getCurrentPage(){ p0+^wXi)
return currentPage; RB 5SK#z
} v pI9TG
Dw-d`8*
/** vgz`+Zj*S
* @param currentPage "y1Iu
* The currentPage to set. =BJe)!b
*/ <W4F`6`x
publicvoid setCurrentPage(int currentPage){ .tngN<f
this.currentPage = currentPage; ~zVxprEf_
}
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/** 'xwCeZcg
* @return 1U 6B$(V^i
* Returns the everyPage. 7]ieBUfS
*/ ([>ecS@eO
publicint getEveryPage(){ z _!ut
return everyPage; }3pM,.
} @<.@X*#I
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/** (3#PKfY+
* @param everyPage <`H0i*|Ued
* The everyPage to set. !X>u.}?g
*/ e+
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publicvoid setEveryPage(int everyPage){
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this.everyPage = everyPage; qQ@| Cj
} 9U8M|W|d
S,Y|;p<+^
/** c}(WniR-"
* @return *@U{[J
* Returns the hasNextPage. K,b
M9>}
*/ 3DU1c?M:
publicboolean getHasNextPage(){ Ndmt$(b
return hasNextPage; Z>[7#;;
} 2*#|t: (c
f5jl$H.
/** +mQ5\14#
* @param hasNextPage =L6#=7hcl
* The hasNextPage to set. Gp"GTPT{
*/ ?J}Q&p.
publicvoid setHasNextPage(boolean hasNextPage){ $( hT{C,K
this.hasNextPage = hasNextPage; $] 6u#5
} @MW@mP)#
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/** Q&9yrx.
* @return P 7x;G5'.
* Returns the hasPrePage. 3h:j.8Z
*/ @"@a70WHk
publicboolean getHasPrePage(){ .3!Wr*o
return hasPrePage; IqOg{#sm
} .sMs_ 5D
s**<=M GK
/** Fq9YhR
* @param hasPrePage Y.:R-|W
* The hasPrePage to set. h2l;xt
*/ ~9X^3.nI
publicvoid setHasPrePage(boolean hasPrePage){ @AyteHK
this.hasPrePage = hasPrePage; \Mf>X\}
} PEMkx"h +
9 {4yC9Oz>
/** G6SgVaM
* @return Returns the totalPage. )rc!irac]
* <p@Cx
*/ @d75X Y Ku
publicint getTotalPage(){ |tXA$}"L8
return totalPage; 4l D$'`
} UaT%tv>}8#
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/** rhv~H"qzW
* @param totalPage 3Ax'v|&Hg
* The totalPage to set. o)`PSw=
*/ }
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publicvoid setTotalPage(int totalPage){ aDlp>p^E>
this.totalPage = totalPage; Fs+tcr/\[
} O
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} )G[byBa
% rBzA<
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w.qtSW6M+
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 BN/4O?jD9
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个PageUtil,负责对Page对象进行构造: w)btv{*
java代码: k"wQ9=HP7
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/*Created on 2005-4-14*/ ~!S3J2kG{
package org.flyware.util.page; sp K8^sh
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import org.apache.commons.logging.Log; ts]e M1;
import org.apache.commons.logging.LogFactory; 1 ZdB6U0
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/** W.wPy@yi
* @author Joa $8EEtr,!
* @"w4R6l+*
*/ CH++3i2&
publicclass PageUtil { Vk5Z[w a
C@M-_Ud>Q
privatestaticfinal Log logger = LogFactory.getLog 8%rD/b6`
hpdI5
(PageUtil.class); ('J/Ww<
So%X(,
|
/** >w,L= z=
* Use the origin page to create a new page >XN[KPTa
* @param page 7iB!Uuc
* @param totalRecords oO}g~<fYG
* @return [4KQcmJc#
*/ u@a){A(P
publicstatic Page createPage(Page page, int y\Wn:RR1 [
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totalRecords){ ,EqQU|
return createPage(page.getEveryPage(), *v<f#hB"
kk4 |4
page.getCurrentPage(), totalRecords); !$I~3_c
} 5epI'D
a@}.96lStD
/** iTxWXij
* the basic page utils not including exception _"DC)
IsXNAYj
handler MT6p@b5
* @param everyPage \PX4>/d@y
* @param currentPage }D1x%L
* @param totalRecords G?Et$r7:R
* @return page `kKssU<
*/ pwSgFc$z
publicstatic Page createPage(int everyPage, int iUkUo x
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currentPage, int totalRecords){ )W\)37=.
everyPage = getEveryPage(everyPage); I| TNo-!$
currentPage = getCurrentPage(currentPage); $<*) 5|6
int beginIndex = getBeginIndex(everyPage, pyEQb#
2- iY:r
currentPage); lZzW-
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int totalPage = getTotalPage(everyPage, y6 (L=$+B
"O$bq::(]e
totalRecords);
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boolean hasNextPage = hasNextPage(currentPage, |mT%IR
=4TQ*;V:
totalPage); $v>q'8d
boolean hasPrePage = hasPrePage(currentPage); M1jT+
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returnnew Page(hasPrePage, hasNextPage, VoCg,gow
everyPage, totalPage, 'h$:~C
currentPage, &X4anH>O
@52#ZWy
beginIndex); w4
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2
} FgdnX2s J
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privatestaticint getEveryPage(int everyPage){
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return everyPage == 0 ? 10 : everyPage; ,fjY|ip
} Qt u;_
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privatestaticint getCurrentPage(int currentPage){ =OufafZb
return currentPage == 0 ? 1 : currentPage; 7cc^n\c?Y
} -jQ*r$iRE
txEN7!
privatestaticint getBeginIndex(int everyPage, int @&T' h}|:
{7y;s
currentPage){ lpi"@3
return(currentPage - 1) * everyPage; _hnsH
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} #H$lBCWI
RO3LZBL
privatestaticint getTotalPage(int everyPage, int T;M
;c.U
tPyk^NJ;
totalRecords){ pPL=(9d
int totalPage = 0; $S>'0mL
^f[6NYS?
if(totalRecords % everyPage == 0) P9!awLM-
totalPage = totalRecords / everyPage; he|Q(?
else " {<X! ^u>
totalPage = totalRecords / everyPage + 1 ; qrMED_(D
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return totalPage; z ]f(lwo{
} `2>p#`
f
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privatestaticboolean hasPrePage(int currentPage){ o
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return currentPage == 1 ? false : true; Ry95a%&/s
} *eg0^ByeD
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privatestaticboolean hasNextPage(int currentPage, _2KIe(,;
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int totalPage){ w|dfl *
return currentPage == totalPage || totalPage == ss-W[|cHU
(]w6q&,
0 ? false : true; e&sH<hWR
} <F^9ML+'
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} Z/,R{Jgt"
GR|\OJ<2
%OoH<\w
w
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HMVP71
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 yjT>bu]
DN:|
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面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 {Q>OZm\+
20I`F>-*
做法如下: 2]kGDeSr
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 k"#gSCW$
4?Y7.:x
的信息,和一个结果集List: aEdA'>
java代码: WIU]>_$.
!<TkX/O
zgY VB}
/*Created on 2005-6-13*/ nlpEkq
package com.adt.bo; VL)<u"d4
H!*ypJ
import java.util.List; #E+ybwA
\MEBQ
import org.flyware.util.page.Page; et5lfj
.I_atv
/** 7 "eK<qJ
* @author Joa =r+K2]z,L
*/ E5i5gE"\
publicclass Result { N]FRL\K
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private Page page; mr7Oi `dE
D>k(#vYKB
private List content; )l9KDObis
ECt<\h7}
/** OPN\{<`*d
* The default constructor kNK0KL
*/ =F|9ac9X
public Result(){ j-d&4,a:c
super(); \^6 [^\@[
} 2|x
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%GTFub0F
/** R?u(aY)P
* The constructor using fields a/uo)']B
* %Bw:6Y4LZ
* @param page xc*a(v0
* @param content q\@_L.tc[
*/ =4` wYh
public Result(Page page, List content){ umns*U%T;
this.page = page; wU|@fm"
this.content = content; #czTX%+9(e
} A|LO!P,w
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/** O?g;Ny
* @return Returns the content. T9R#.y,
*/ .K84"Gdx
publicList getContent(){ lrZ]c:%k
return content; :%&
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} -TVwoK
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/** 3!8(A/YP;
* @return Returns the page. 4Q0ZY(2 EO
*/ `(HvD] l
public Page getPage(){ P@PF"{S
return page; ^'[QCwY~
} >3p~>;9sc
E"9(CjbQ[
/** \(Oc3+n6
* @param content HL&HY)W1gf
* The content to set. 0)SRLHTY%
*/ <oJ?J^
public void setContent(List content){ t$du|q(
this.content = content; rO>'QZ%
} /69yR
|'-aR@xJ
/** !#pc@(rE
* @param page ;@=3
@v
* The page to set. ;[;WEA
*/ t@R[:n;+
publicvoid setPage(Page page){ wxqX42v
this.page = page; mDK*LL5]W
} -&D=4,#
} K@*+;6y@
I'*,<BPG
@Dfg6<0
rX)&U4#[m
+z nlf-
2. 编写业务逻辑接口,并实现它(UserManager,
>=97~a+.
;&<N1
UserManagerImpl) la<.B^
java代码: .KKecdd?=
r QiRhp
MJch
Z
/*Created on 2005-7-15*/ 9V1d`]tP
package com.adt.service; ic`BDkNO
iXy1{=BDv
import net.sf.hibernate.HibernateException; FbroI>" e
nEu:& 4
import org.flyware.util.page.Page; Ik^^8@z
+Kb 7N, "
import com.adt.bo.Result; xh:I]('R
- (WH+
/** h#Z["BG
* @author Joa {Vj&i.2,
*/ w[d8#U
publicinterface UserManager { w r"0+J7
c45s
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public Result listUser(Page page)throws r<fcZ)jt|
P}~MO)*1
HibernateException; m6[}KkW
,V,mz?d^9
} ya1
aWs~
(9RfsV4^
7:olStK
,93Uji[l
LUD.
java代码: qr4 lr!#t
_|["}M"?
ss%,
/*Created on 2005-7-15*/ pWKE`x^
package com.adt.service.impl; WfaMu|
L
9[zxq`qT}+
import java.util.List; A0Nx?
*gH]R*Q[Rt
import net.sf.hibernate.HibernateException; b]b>i]n
y@l&B+2ks
import org.flyware.util.page.Page; :pdX
import org.flyware.util.page.PageUtil; V5(_7b#z``
FA*$ dwp
import com.adt.bo.Result; P9yMf~
import com.adt.dao.UserDAO; %Zk6K!MY#
import com.adt.exception.ObjectNotFoundException; d~qQ_2M[G
import com.adt.service.UserManager; U.,S.WP+d
=_ pSfKR;
/** AwNr}9`
* @author Joa "W"^0To
*/ vcdVck@
publicclass UserManagerImpl implements UserManager { " Bx@(
GIzB1cl:
private UserDAO userDAO; Op-z"inw
)9"^ D
/** ^'E^*R
* @param userDAO The userDAO to set. 6}-No
*/ W"Y)a|rG%
publicvoid setUserDAO(UserDAO userDAO){ y@7fR9hp<
this.userDAO = userDAO; I9zs
} P6.PjK!Ar
9oJM?&i
/* (non-Javadoc) s0dP3tz>
* @see com.adt.service.UserManager#listUser nQmHYOF%
q~
aFV<Q
(org.flyware.util.page.Page) nSyLt6zn\
*/ +]cf/_8+s
public Result listUser(Page page)throws }
doAeTZ
3GF67]
HibernateException, ObjectNotFoundException { 2>9\o]ac4
int totalRecords = userDAO.getUserCount(); F}So=Jz9h
if(totalRecords == 0) ]6B9\C.2-_
throw new ObjectNotFoundException b_RO%L:"yL
`B@eeXa;u
("userNotExist"); 5NZuaN
page = PageUtil.createPage(page, totalRecords); Jm<NDE~rw
List users = userDAO.getUserByPage(page); syBpF:`-W
returnnew Result(page, users); 1<'z)r4
} D/Ki^E
/al56n
} FTCIfW
<VhmtT%7
THhxj)
_y[C52,
R 9`[C
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 zN!W_2W*
[@lK[7 u
询,接下来编写UserDAO的代码: 6:G&x<{
3. UserDAO 和 UserDAOImpl: GKIzU^f
java代码: n7bVL#Sq[
9JP:wE~y
yS~Y"#F!.
/*Created on 2005-7-15*/ UUDUda
package com.adt.dao; +@?Q "B5u}
>`UqS`YQK
import java.util.List; dP_QkO
>hNSEWMY`
import org.flyware.util.page.Page; CWkWW/ZI
"}Om0rB}1
import net.sf.hibernate.HibernateException; tcj"rV{G
=h4uN,
/** IW!x!~e
* @author Joa "<0 !S~]
*/ +h"i6`g
publicinterface UserDAO extends BaseDAO { 5%\K
K>+ v" x
publicList getUserByName(String name)throws uuEvH<1
*d C| X
HibernateException; 5
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5Jo'h]
publicint getUserCount()throws HibernateException; m+'1c}n^7
-lJ|x>PG'
publicList getUserByPage(Page page)throws &m