Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Bn:sN_N
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 a8c]B/
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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 PyE<`E
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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`]1W,t
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。 #oY7v,x\
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分页支持类: NebZGD2K
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java代码: b7mP~]V
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package com.javaeye.common.util; ,/9|j*9H
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import java.util.List; FFGTIT# {"
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publicclass PaginationSupport { j]^]p;An
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publicfinalstaticint PAGESIZE = 30; cKAl 0_[f"
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privateint pageSize = PAGESIZE; KQ3
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privateList items; .jw)e!<\N
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privateint totalCount; s#3{c@^3
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privateint[] indexes = newint[0]; ?9A[;j|a0
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privateint startIndex = 0; u:$x,Q
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public PaginationSupport(List items, int I%`2RXBt3^
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totalCount){ ]gZjV
setPageSize(PAGESIZE); D![Twlll
setTotalCount(totalCount); {ar}.U
setItems(items); ptcU_*Gd
setStartIndex(0); xB#E&}Ho
} cAS5&T<
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public PaginationSupport(List items, int EC0auB7G
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totalCount, int startIndex){ <[bDNe["?
setPageSize(PAGESIZE); I\_ R&
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setTotalCount(totalCount); ;z#9>99rH
setItems(items); {JJ`|*H$_
setStartIndex(startIndex); *(rE<
} l{4\Wn Va
* ?K=;$
public PaginationSupport(List items, int 4=Zlsp
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totalCount, int pageSize, int startIndex){ ` {p5SYj
setPageSize(pageSize); &k nnWm"
setTotalCount(totalCount); bvG
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setItems(items); >vhyKq|g<
setStartIndex(startIndex); i y 5
} ZpyRvDz
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publicList getItems(){ jWz-7BO
return items; \?ZdUY
} U&NOf;h$
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publicvoid setItems(List items){ 7>'F=}6[Y
this.items = items; g=.5*'Xlp
} c/u;v69r
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publicint getPageSize(){ KME
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return pageSize; ;S7xJ'H
} ntT|G0E
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publicvoid setPageSize(int pageSize){ T-\,r
this.pageSize = pageSize; gM8 eO-d
} c8u0\X,
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i
publicint getTotalCount(){ 1NTe@r!y
return totalCount; <KpQu%2(
} y.Py>GJJ1S
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publicvoid setTotalCount(int totalCount){ 4}CRM# W2
if(totalCount > 0){ .&ZVy{uP
this.totalCount = totalCount; {:Q2Itsy
int count = totalCount / |Yx8Ez
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pageSize; O]>Or3oO
if(totalCount % pageSize > 0) km^AX:r1
count++; z(ajR*\#
indexes = newint[count]; B@4#y9`5
for(int i = 0; i < count; i++){ I'gnw~
indexes = pageSize * x[X.// :
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} V6L_aee}CK
}else{ M$)+Uo2
this.totalCount = 0; ~^eAS;
} o.Q9kk?L
} PQK_*hJG"
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publicint[] getIndexes(){ Kk,->q<1
return indexes; 9T]]T Ev4
} \S9z.!7v$
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publicvoid setIndexes(int[] indexes){ Bw$-*FYE
this.indexes = indexes; ns3k{l#
} *,. {Xf
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publicint getStartIndex(){ y|aWUX/a
return startIndex; yD KX,
} L=$P
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publicvoid setStartIndex(int startIndex){ L \$zr,=C
if(totalCount <= 0) \8pbPo=x
this.startIndex = 0; yP-Dj
,
elseif(startIndex >= totalCount) I}:/v$btM
this.startIndex = indexes *n47.(a2i
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[indexes.length - 1]; 'fB `e]_
elseif(startIndex < 0) dcA0k
this.startIndex = 0; IoX(Pa
else{ L/ZZe5I
this.startIndex = indexes #Ky0` n
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[startIndex / pageSize]; {r"s.|n
} f9$98SI
} VS`S@+p
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publicint getNextIndex(){ T|m+ULp~
int nextIndex = getStartIndex() + ~$@I <=L
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pageSize; 3lJK[V{'#'
if(nextIndex >= totalCount) aV ^2
return getStartIndex(); 6QV/8IX
else B<)(7GTv7"
return nextIndex; 8dpVB#]pp,
} -&&mkK
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publicint getPreviousIndex(){ TQ BL!w
int previousIndex = getStartIndex() - Pa.!:N-
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pageSize; >3ODqRu
if(previousIndex < 0) B)(A#&nrb
return0; 7}*5Mir p
else .B)v "Sw#
return previousIndex; ":Q70*xSm
} us]ah~U6A
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} aCMcu\rd
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抽象业务类 K@fxCj*}
java代码: DJbj@ 2W[
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/** cz0tnF*&
* Created on 2005-7-12 JvG t=v
*/ Vf:t!'WD?2
package com.javaeye.common.business; |X sW)/
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import java.io.Serializable; .`iq+i~
import java.util.List; l"-D@]"
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import org.hibernate.Criteria; C>;}CH|X
import org.hibernate.HibernateException; iU3co|q7
import org.hibernate.Session; NO<myN+N
import org.hibernate.criterion.DetachedCriteria; DQ~@=%?ni
import org.hibernate.criterion.Projections; .v;Npm2
import .-r
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org.springframework.orm.hibernate3.HibernateCallback; =?}'\
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import )FB)ZK ;
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org.springframework.orm.hibernate3.support.HibernateDaoS Jn&(v"_
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upport; ,Pl[SMt!
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import com.javaeye.common.util.PaginationSupport; |.,yM|
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public abstract class AbstractManager extends <l\FHJhjq
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HibernateDaoSupport { > {:8c-\2}
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privateboolean cacheQueries = false; :c6%;2
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privateString queryCacheRegion; Ji7A9Hk
;[|x5o/<
publicvoid setCacheQueries(boolean gcz1*3)
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cacheQueries){ ~r{Nc j
this.cacheQueries = cacheQueries; gh~C.>W}q+
} lr|-_snx2
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publicvoid setQueryCacheRegion(String j\ )Qn2r
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queryCacheRegion){ R%ddB D\?
this.queryCacheRegion = ($3QjH_@
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queryCacheRegion; l@^RbF['
} B
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publicvoid save(finalObject entity){ aB$Y5
getHibernateTemplate().save(entity); !?KY;3L:
} x|Q6[Y
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publicvoid persist(finalObject entity){ Pukq{/27
getHibernateTemplate().save(entity); c,+oH<bZZs
} 5Po.&eS
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publicvoid update(finalObject entity){ \zKVgywR
getHibernateTemplate().update(entity); s*S@}l
} \Q#F&q0
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publicvoid delete(finalObject entity){ NSx DCTw
getHibernateTemplate().delete(entity); 8`im4.~#%
} No[>1]ds
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publicObject load(finalClass entity, amPQU
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finalSerializable id){ "=qdBG9
return getHibernateTemplate().load Q@M,:0+cy
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(entity, id); 9m#`56G`
} [@/G?sAQm\
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publicObject get(finalClass entity, R=E )j^<F
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finalSerializable id){ )2R:P`U
return getHibernateTemplate().get Kyv$yf9
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(entity, id); HC$_p,9OV
} /+3|tb
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publicList findAll(finalClass entity){ XX/cJp
return getHibernateTemplate().find("from {gJOc,U4b
ny#7iz/
" + entity.getName()); ;Yi ;2ttW
} 8(ZQD+U(9F
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publicList findByNamedQuery(finalString ??k^Rw+0R
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namedQuery){ "--rz;+K
return getHibernateTemplate zRu}lJ1#W$
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().findByNamedQuery(namedQuery); P$qIB[Xi
}
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publicList findByNamedQuery(finalString query, @O4m-Oosi
/Cwt4.5
finalObject parameter){ >bmL;)mc&
return getHibernateTemplate
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().findByNamedQuery(query, parameter); z<)?8tAgq
} TG'A'wXxy
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publicList findByNamedQuery(finalString query, Rh:\/31~
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finalObject[] parameters){ d]+g3oy
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return getHibernateTemplate 3{
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().findByNamedQuery(query, parameters); 6n<:ph,h;
} zaX30e:R
>\MV/!W
publicList find(finalString query){ c~p4M64
return getHibernateTemplate().find R$v{ p[
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(query); {GZHD^Ce
} 3vmZB2QG
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publicList find(finalString query, finalObject
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parameter){ t R*JM$T
return getHibernateTemplate().find Z~$fTW6g
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(query, parameter); F!N;4J5u
} tZ4W]od
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public PaginationSupport findPageByCriteria bp;)*
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(final DetachedCriteria detachedCriteria){ IaN|S|n~
return findPageByCriteria ,p0R4gi
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); hO\_RhsRy?
} (5VP*67
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public PaginationSupport findPageByCriteria ]yA|
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(final DetachedCriteria detachedCriteria, finalint !*N#}6Jd
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startIndex){ ~M+|g4W%
return findPageByCriteria ]w! x
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(detachedCriteria, PaginationSupport.PAGESIZE, fokOjTE
6?z&G6
startIndex); QD q2<
} 0l{').!_
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public PaginationSupport findPageByCriteria EcFYP"{U
)k=8.j4
(final DetachedCriteria detachedCriteria, finalint [\eUCt F
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pageSize, miEfxim
finalint startIndex){ =]&R6P>
return(PaginationSupport) J7_'@zU
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getHibernateTemplate().execute(new HibernateCallback(){ Peh(*D{
publicObject doInHibernate $0NWX
J3g>#N]='(
(Session session)throws HibernateException { U*1rA/"n
Criteria criteria = rB)m{)
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detachedCriteria.getExecutableCriteria(session); A\k@9w\Ll;
int totalCount = DBbmM*r
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((Integer) criteria.setProjection(Projections.rowCount ct fKxGH
DSD#',
()).uniqueResult()).intValue(); \snbU'lfP
criteria.setProjection H>a3\M
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(null); 3Ud&B
List items = pu,/GBG_
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criteria.setFirstResult(startIndex).setMaxResults G{$9e}#
t&eY+3y,T
(pageSize).list(); zH}u9IR3`
PaginationSupport ps = D3vd O2H
,m9Nd "6\
new PaginationSupport(items, totalCount, pageSize, A:0
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startIndex); m},nKsO
return ps; wnN@aO6g*
} 9c4 6|
}, true); 1DN,
} qdjRw#LS^q
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public List findAllByCriteria(final j"yL6Q9P
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DetachedCriteria detachedCriteria){ [P`Q_L,+
return(List) getHibernateTemplate #c./<<P5}
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().execute(new HibernateCallback(){ >5i1M^g(
publicObject doInHibernate m%'9z L c
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(Session session)throws HibernateException { Y6W3WPs(
Criteria criteria = rM/*_0[`d
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detachedCriteria.getExecutableCriteria(session); !nU
return criteria.list(); `3*>tq
} w1h07_u;v
}, true); "u3
} Oh5(8.<y
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public int getCountByCriteria(final {y)s85:t
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DetachedCriteria detachedCriteria){ XGk8Ki3w
Integer count = (Integer) ^4`q%_vm
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getHibernateTemplate().execute(new HibernateCallback(){ tlA4oVII
publicObject doInHibernate N"2P&Ho]
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(Session session)throws HibernateException { kS8srT
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Criteria criteria = vWXj6}
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detachedCriteria.getExecutableCriteria(session); 1W"9u
return JU1U=Lu."
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criteria.setProjection(Projections.rowCount WIQt5=-
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()).uniqueResult(); H7H'0C
} Gg{@]9
}, true); Z"mpE+U*
return count.intValue(); h,\^Sb5AP
} pIqPIuy
} 1e _V@Vy
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用户在web层构造查询条件detachedCriteria,和可选的 :nd
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 /e!/
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PaginationSupport的实例ps。 _r+9S.z
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ps.getItems()得到已分页好的结果集 M+ ^]j
ps.getIndexes()得到分页索引的数组 pr>K#@^
ps.getTotalCount()得到总结果数 n,9 *!1y
ps.getStartIndex()当前分页索引 Z>7Oez>
ps.getNextIndex()下一页索引 w(k7nGU]
ps.getPreviousIndex()上一页索引 {t;Q#Ou.
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 #OJsu
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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 :{E3H3
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一下代码重构了。 aEy_H-6f
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我把原本我的做法也提供出来供大家讨论吧: TEE$1RxV(
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首先,为了实现分页查询,我封装了一个Page类:
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java代码: YEXJh!X
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/*Created on 2005-4-14*/ H
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package org.flyware.util.page; 0;!aO.l]K
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/** (=)+as"u9*
* @author Joa >M[rOu
(d
* Q^Y>T&Q
*/ X`.4byqdK
publicclass Page { <;Qle
n?YGXW/
/** imply if the page has previous page */ ]Q6,,/nn
privateboolean hasPrePage; Q5Y4@
k#5S'sCF<
/** imply if the page has next page */ Rdwr?:y(]
privateboolean hasNextPage; wAVO%8u
:kOLiko!4>
/** the number of every page */ oMkB!s
privateint everyPage; ?Xlmt$Jp
rw
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/** the total page number */ "P&|e|7
privateint totalPage; #Ru+|KL
%Kw5b ;
/** the number of current page */ ?N,a {#w
privateint currentPage; 2a (w7/W:
}]=b%CPJh+
/** the begin index of the records by the current f|m.v
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Jn'q'+
query */ FnvN 4h{S
privateint beginIndex; .: 87B=
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/** The default constructor */ |jEKUTv,G
public Page(){ P2 !~}{-
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} Mff_j0D
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/** construct the page by everyPage R+]Fh4t
* @param everyPage P-7!\[];te
* */ wAF>C[ <\
public Page(int everyPage){ 96}/;e]@
this.everyPage = everyPage; `w[0q?}"`
} FGy7KVR
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/** The whole constructor */ m&Ms[X
public Page(boolean hasPrePage, boolean hasNextPage, qWw@6VvoQ
"h2;65@
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int everyPage, int totalPage, U87VaUr
int currentPage, int beginIndex){ *h@nAB\3
this.hasPrePage = hasPrePage; <saS2.4
this.hasNextPage = hasNextPage; )#xd]~<
this.everyPage = everyPage; v srce
this.totalPage = totalPage; ;s9!ra:3
this.currentPage = currentPage; X'7 T" 5!
this.beginIndex = beginIndex; cK@O)Ko}
} %nFZA)B[
gS4K](KH |
/** ` *$^rQS
* @return &{Uaa
* Returns the beginIndex. dQ/Xs.8
*/ h+R}O9BD
publicint getBeginIndex(){ g#Zb}^
return beginIndex; BL]!j#''KE
} yoGE#+|7^
vQc>jmS+n
/** ]9R?2{"K
* @param beginIndex s^L\hr
* The beginIndex to set. "y_$!KY%
*/ h*_r='
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publicvoid setBeginIndex(int beginIndex){ o'>jO.|
this.beginIndex = beginIndex; v@Otp
} )K8JDP
ir \ d8.
/** djZOx;/
* @return I".d>]16|
* Returns the currentPage. 0t/ S_Q
*/ ~
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publicint getCurrentPage(){ A`#5pGR
return currentPage; V0wK.^]+}/
} }9 qsPn
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/** #uu wzE*M_
* @param currentPage }gag?yQ.^
* The currentPage to set.
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*/ /e4hB
publicvoid setCurrentPage(int currentPage){ Qy0bp;V/
this.currentPage = currentPage; !%T@DT=l&
} &b"PjtU.X
/5U?4l(6[f
/** /3FC@?l
w4
* @return :L*CL 8m
* Returns the everyPage. l]oGhM;
*/ z#D@mn5\a
publicint getEveryPage(){ J@!Sf7k42
return everyPage; _ F@>?\B
} CDU^X$Q
Gx'mVC"{
/** 2=["jP!B
* @param everyPage KhXW5hS1
* The everyPage to set. |\~cjPX(
*/ Bi?.G7>
publicvoid setEveryPage(int everyPage){ ~Z.lvdA_5
this.everyPage = everyPage; 34s:|w6y
} wz073-v>ZV
/vsQ <t;~
/** J*a`qU
* @return `=q)-y_C
* Returns the hasNextPage. +SUQRDF@i
*/ Yw?%>L
publicboolean getHasNextPage(){ JfKl=vg
return hasNextPage; D'uzH|z8
} sx`C<c~u
WXO@oZ!
/** zcIZJVYA
* @param hasNextPage r4!zA-{
* The hasNextPage to set. ,h8)5Mj/J
*/ o#%2N+w
publicvoid setHasNextPage(boolean hasNextPage){ 2MtaOG2l&q
this.hasNextPage = hasNextPage; 5x=tOR/h
} &S''fxGL
Nm#KHA='Z
/** Bk?M F6
* @return -PEpy3dMY
* Returns the hasPrePage. 9)l[$X
*/ h7gH4L!'u
publicboolean getHasPrePage(){ MttVgNV
return hasPrePage; <aL$d7
} X@|
ro^Y$;G
/** bG2!5m4L
* @param hasPrePage 7v%~^l7:x
* The hasPrePage to set. ~q-|cl<
*/ W9a H]9b
publicvoid setHasPrePage(boolean hasPrePage){ &W".fRH_O
this.hasPrePage = hasPrePage; TO3Yz3+A
} &*/X*!_HK
EG<K[t
/** pm3?
* @return Returns the totalPage. ;}^Pfm8
* J~n{gT<L
*/ 'T+3tGCy+
publicint getTotalPage(){ P(A%z2Ql
return totalPage; NrS1y"#d9
} oBAD4qK
(Ozb +W?
/** )9L1WOGi
* @param totalPage - Npl x
* The totalPage to set. }tc,3>/
*/ pX6OhwkTK
publicvoid setTotalPage(int totalPage){ auL?Hb
this.totalPage = totalPage; tao3Xr^?
} /c3DltOdr
~~'XY( \L@
} N:"E%:wSbi
qC`"<R=GX
3ywBq9FGhp
E
hd*
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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 O6k[1C
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个PageUtil,负责对Page对象进行构造: 1Voo($q.
java代码: ]2K>#sn-]
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p]=8=pE<
/*Created on 2005-4-14*/ o?/N4$&5l
package org.flyware.util.page; 9Z7o?S";
- DL/Hk_r
import org.apache.commons.logging.Log; KWN0$*4
import org.apache.commons.logging.LogFactory; ke)3*.Y%C
"o=h /q5&
/** %"+FN2nbm
* @author Joa MJ&6 Z*
* ?Mji'ZW}
*/ >$HMZbsE
publicclass PageUtil { a/`fJY6rR
4.CLTy3W
privatestaticfinal Log logger = LogFactory.getLog GD~3RnGQ{
hMi!H.EX.
(PageUtil.class); f-4<W0%
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/** IxgnZX4N
* Use the origin page to create a new page AVyo)=&
* @param page ROQk^
* @param totalRecords $ZwsTV]x
* @return y(6&90cr
*/ /Hx%gKU
publicstatic Page createPage(Page page, int /M B0%6m
h/eKVRGs"
totalRecords){ kwZC3p\\
return createPage(page.getEveryPage(), fs~n{z,ja%
J"FKd3~:E
page.getCurrentPage(), totalRecords); NoZz3*j=
} .eq-i>
!=q {1\#
/** %o+bO}/9
* the basic page utils not including exception LFV;Y.-(h
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handler +(UrqK4Av
* @param everyPage [-vd]ob
* @param currentPage <~X=6
* @param totalRecords M8S4D&vpD4
* @return page fs>0{
*/ lKH"PH7*_w
publicstatic Page createPage(int everyPage, int u+th?KO`
|WubIj*\{
currentPage, int totalRecords){ ?ix0n,m
everyPage = getEveryPage(everyPage); ] p'+F
currentPage = getCurrentPage(currentPage); M}/%t1^g:
int beginIndex = getBeginIndex(everyPage, cGOE $nL
<Hm:#<\
currentPage); ?CL1^N%
int totalPage = getTotalPage(everyPage, pB?a5jpA
B:+}^=
totalRecords); }u:^ Mz
boolean hasNextPage = hasNextPage(currentPage, dpE\eXoa,
{&w%3
totalPage); }wj*^>*
boolean hasPrePage = hasPrePage(currentPage); )k29mqa`
kD MS7y<s
returnnew Page(hasPrePage, hasNextPage, R!}B^DVt
everyPage, totalPage, uyjZmT/-
currentPage, YJeZ{Wws
nGX~G^mZ
beginIndex); _Y\@{T;^Zb
} vk;>#yoox
!Me%W3
privatestaticint getEveryPage(int everyPage){ vaR0`F
return everyPage == 0 ? 10 : everyPage; ,ulNap"R
} &WvJg#f
'#u2q=n4*
privatestaticint getCurrentPage(int currentPage){ bis/Nfr]
return currentPage == 0 ? 1 : currentPage; iWQBo>x
} !i}G>*XH,
|W*f6F3
privatestaticint getBeginIndex(int everyPage, int &~||<0m
>fs-_>1d
currentPage){ JJ qX2B
return(currentPage - 1) * everyPage; uvD6uIW<
} %,~; w0
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privatestaticint getTotalPage(int everyPage, int A[+op'>k
/1n}IRuw
totalRecords){ #J^p,6
int totalPage = 0; D|9B1>A,m
ub4(mS
if(totalRecords % everyPage == 0) Arfq
totalPage = totalRecords / everyPage; HzbO#)Id-I
else C. 8>
totalPage = totalRecords / everyPage + 1 ; Ds L]o
?ADk`ts~,}
return totalPage; 1T}|c;fc
} +".&A#wU
mn0QVkb}lc
privatestaticboolean hasPrePage(int currentPage){ YhR?*Di
return currentPage == 1 ? false : true; "NC(^\l/
} FopD/D{
<w{W1*R9
privatestaticboolean hasNextPage(int currentPage, '[\%P2c)Q
*p.ELI1IC
int totalPage){ :*c@6;2@
return currentPage == totalPage || totalPage == \O7,CxD2
2(`2 f
0 ? false : true; @J"
} ~Y
} Ux zwgVT
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} nV']^3b
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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。 YWq[)F@0G
`4;<\VYCr
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 O]{H2&k@
X8;03EW;
做法如下: unD8h=Z2
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 o/=K:5
$I1p"6
的信息,和一个结果集List: \?qXscq
java代码: |l)Oy#W
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z$;%SYI
/*Created on 2005-6-13*/ lD C74g
package com.adt.bo; w2$HP/90j
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import java.util.List; hb?
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_MMz x2}
import org.flyware.util.page.Page; YT&_{nL#\
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/** kN>d5q9b%X
* @author Joa 7Jc=`Zm'
*/ zWjGGTP~3&
publicclass Result { 3_Oq4 /
n]8_]0{qi
private Page page; +;;fw |/
EidIi"sr
private List content; DlIfr6F
Pu
axS
/** T<! `~#kM
* The default constructor ?pQ, 5+8
*/ }T(|\
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public Result(){ 70KXBu<6
super(); {v]>sn;P1
} >O\-\L
9=JU&/!
/** \vm'D'9
* The constructor using fields c#{<|
.
* F1%'
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* @param page #+_OyZ*
* @param content vZ|-VvG
*/ I;mtyS
public Result(Page page, List content){ 4]
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this.page = page; p1Lx\
this.content = content;
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} \=5CNe
2d1'!B
zDA
/** "aa6W
* @return Returns the content. 1bj75/i<6
*/ 1U"Y'y2
publicList getContent(){ !' sDqBZ&7
return content; Ho"FB|e
} 9"V27"s
\t!+]v8f8
/** KrbNo$0%
* @return Returns the page. y?5*K
*/ r0S7e3xb
public Page getPage(){ Hs-NP#I
return page; )n0g6
} %8 4<@f&n]
'`3-X];p
/** Ogjjjy84vM
* @param content &"^A
* The content to set. N8nyTPw
*/ #Q$4EQB
public void setContent(List content){ {[Yv@CpN
this.content = content; yY&(?6\{<<
} 3q1O:b^eo
93'%aSDI%
/** h+*
* @param page
Box,N5AA
* The page to set. 9)4N2=
*/ H!45w;,I
publicvoid setPage(Page page){ p.l]%\QI
this.page = page; ".w*_1G7U
} |]m&LC
} I1}{7-_t
9r8{9h:
}xdI{E1 q)
X=.+XP]
n*O/X
2. 编写业务逻辑接口,并实现它(UserManager, 7q67_u?@
t*D[Q$v
UserManagerImpl) &.4lhfI+(Q
java代码: (bT\HW%m
L>@6lhD)x
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/*Created on 2005-7-15*/ 0kiW629o
package com.adt.service; Rw.
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L)w& f
import net.sf.hibernate.HibernateException; 2"i<--Y
a7d782~
import org.flyware.util.page.Page; }RoM N$r
WQK#&r*
import com.adt.bo.Result; ;^
/9sLW?#
x]{h$yI
/** ]gmf%g'C
* @author Joa ?Rl*5GRW
*/ M_XZOlW5
publicinterface UserManager { !-;Me&"I=`
O%+:fJz6wI
public Result listUser(Page page)throws m&$H?yXW>
%{Ls$Y)
HibernateException; >w*"LZjTTK
|]`+@K,S
} {fGi:b\[ 8
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Jl9T[QAJn1
zJx<]=]
-l,ib=ne
java代码: ,-{j.
u_Q3v9
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/*Created on 2005-7-15*/ [I^SKvM
package com.adt.service.impl; I &m~ cBj<
a}Ov@7
import java.util.List; WQ*$y3%
0`S!+d
import net.sf.hibernate.HibernateException; =1esUO[nx
qi)(\
import org.flyware.util.page.Page; c?opVbJB\
import org.flyware.util.page.PageUtil; +"SBt}1
Az.Y-O<$\
import com.adt.bo.Result; TVjY8L9'h
import com.adt.dao.UserDAO; [S<DdTY9hZ
import com.adt.exception.ObjectNotFoundException; i;\i4MT
import com.adt.service.UserManager; Z,d/FC#y(
@*c+`5)_
/** x[>A'.m@)
* @author Joa eEU:
*/ Q%
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publicclass UserManagerImpl implements UserManager { RL&*.r&
KlrKGmy,)
private UserDAO userDAO; N.&K"J
w1GCjD*y
/** qrdA?VV
* @param userDAO The userDAO to set. o?%x!m>
*/ xpS#l"dr
publicvoid setUserDAO(UserDAO userDAO){ c/hml4
this.userDAO = userDAO; TIvLY5 HG
} d?S<h`{x
7C 4Njei"
/* (non-Javadoc) Np=*B_ @8
* @see com.adt.service.UserManager#listUser U5"F1CaW~
@lmk e>
(org.flyware.util.page.Page) nTHP~]
*/ )*_YeT&w.
public Result listUser(Page page)throws ]-AT(L>
Z6
aT%7}}
HibernateException, ObjectNotFoundException { 3'']q3H
int totalRecords = userDAO.getUserCount(); l'o}4am
if(totalRecords == 0) P/y-K0u
throw new ObjectNotFoundException ^X_%e |
W&*{j;e9%I
("userNotExist"); t4JGd)r
page = PageUtil.createPage(page, totalRecords); J,q:
List users = userDAO.getUserByPage(page); $>BP}V33
returnnew Result(page, users); qt1#P
} qM9GW`CKA
f/=0
} ec3('}X
):\pD]e
[XQNgSy?z
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 @TH \hr]
M)LdGN?$
询,接下来编写UserDAO的代码: BHK_=2WYz
3. UserDAO 和 UserDAOImpl: vAVoFL
java代码: GN>T }
+V'Z%;/
WK=!<FsC$
/*Created on 2005-7-15*/ 1/{:}9Z@
package com.adt.dao; 2HTZ,W
I @z{Gr
import java.util.List; -~aVt~{k/
gWlmQl
import org.flyware.util.page.Page; ]ny(l#Hu:
t]vz+VQ
import net.sf.hibernate.HibernateException; L8$7^muad
sVC5<?OW!p
/** @
J"1!`
* @author Joa .:;i*
*/ kt S0
publicinterface UserDAO extends BaseDAO { x/Ds`\
Q7SS<'(
publicList getUserByName(String name)throws 2
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S\ li<xl
HibernateException;
Dho~6K}"
&/zsIx+
publicint getUserCount()throws HibernateException; L3W
^ip4
AI)9E=D%
publicList getUserByPage(Page page)throws uUJ2d84tV
Yw{](qG7e`
HibernateException; w5[POo' 5
w?/,LV
} r>G$u
%_z]iz4
fkI<RgM
Zkz:h7GUG-
@&~BGh
java代码: mDq01fU4
tL3(( W"
U "}Kth
/*Created on 2005-7-15*/ Z2`e*c-[E
package com.adt.dao.impl; MJD4#G
JRNyvG>j
import java.util.List; 0\mM^+fO
<iMkHch
import org.flyware.util.page.Page; {<_}[} XY
I{2e0
import net.sf.hibernate.HibernateException; zJV4)
import net.sf.hibernate.Query; ~<$8i}7
G)putk@
import com.adt.dao.UserDAO; r&H>JCRZ<=
^]v}AEcmW
/** %]
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* @author Joa i|=XW6J%
*/ cvC;QRx
public class UserDAOImpl extends BaseDAOHibernateImpl Npu;f>g0_
&zm5s*yNt
implements UserDAO { ?&