Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 sR%,l
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 yj]\%3o<Z7
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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 f#9DU}2m
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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 jU
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分页支持类: []e*Io&[
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java代码: j\t"4=,n
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package com.javaeye.common.util; Yjo$^q
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import java.util.List; /W !A^
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publicclass PaginationSupport { &^-quzlZ
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publicfinalstaticint PAGESIZE = 30; \qPgQsy4
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privateint pageSize = PAGESIZE; -u6`B-T
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privateList items; E&G_7->
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privateint totalCount; 2+G_Y>
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privateint[] indexes = newint[0]; VU>s{_|{
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privateint startIndex = 0; V+A1O k)
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public PaginationSupport(List items, int Y4PU~l
,"/<N*vh
totalCount){ 9gMNS6D'b
setPageSize(PAGESIZE); l\l\T<wa,
setTotalCount(totalCount); m4:b?[
setItems(items); G6X
setStartIndex(0); g+ `Ie'o<
} #+Lo&%p#3
ye U4,Ko
public PaginationSupport(List items, int Q}!U4!{i|p
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totalCount, int startIndex){ 64s9Dy@%F
setPageSize(PAGESIZE); lyzMKla"
setTotalCount(totalCount); >M7e'}0;
setItems(items); >mI-h
setStartIndex(startIndex); B^(0>Da\
} 45`Gv
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public PaginationSupport(List items, int A0*u(15%
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totalCount, int pageSize, int startIndex){ L4SvE^2+
setPageSize(pageSize); p\e*eV1dxx
setTotalCount(totalCount); 1 sCF
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setItems(items); UP:+1Sp9
setStartIndex(startIndex); }#@P+T:b
} _:om(gL
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publicList getItems(){ ~..h=
return items; jr"~
} cXcn}gKV
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publicvoid setItems(List items){ <wTkPErUG
this.items = items; <PkDfMx2
} j#%*@]>Tg
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publicint getPageSize(){ zx{\SU
return pageSize; 6m21Y8N
} ?,|_<'$4T
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publicvoid setPageSize(int pageSize){ \@4QG.3&
this.pageSize = pageSize; wP/rR D6
} ox {Cm
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publicint getTotalCount(){ b]6;:Q!d
return totalCount; u7`<m.\
} iZ[o2Tre
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publicvoid setTotalCount(int totalCount){ ; ,*U,eV
if(totalCount > 0){ X4i$,$C
this.totalCount = totalCount; Z<y+D-/
int count = totalCount / =fBJQK2sk
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pageSize; vE?qF9I{$0
if(totalCount % pageSize > 0) Y_PCL9G{p
count++; =]7|*-
indexes = newint[count]; ~;m~)D
for(int i = 0; i < count; i++){ 0*:]eM};P
indexes = pageSize * J#@" Yb
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i; ) !ZA.sx
} ika{>hbH
}else{ (B]Vw+/
this.totalCount = 0; ~"EkX
} m{Q{ qJ5>
} V6wYJ$]
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publicint[] getIndexes(){ 3SQ
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return indexes; $Ry
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} T:cSv
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publicvoid setIndexes(int[] indexes){ oB9Fas!N
this.indexes = indexes; 2T?t[;-
} 40%p
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publicint getStartIndex(){ +}4vdi"
return startIndex; jy@}$g{
} 7-e)V{A`w
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publicvoid setStartIndex(int startIndex){ )Y?Hf2']
if(totalCount <= 0) f<|8NQ2y.
this.startIndex = 0; O";r\Z
elseif(startIndex >= totalCount) XfbkK )d
this.startIndex = indexes 0]>p|m9K^<
4B]8Mp~\aL
[indexes.length - 1]; *o"F.H{#N
elseif(startIndex < 0) i8HSYA
this.startIndex = 0; =K8`[iH
else{ GUat~[lUrj
this.startIndex = indexes !h9 An
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[startIndex / pageSize]; uX}M0W
} C
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} MzK&Jh
kV6>O C&^
publicint getNextIndex(){ |k
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int nextIndex = getStartIndex() + 8n~@Rj5
zi*D8!_C
pageSize; yJb;V#
if(nextIndex >= totalCount) DU1,i&(
return getStartIndex(); nsgNIE{>gO
else ,st4K;-
return nextIndex; ?Cu#(
} sMO3eNLn
,u]kZ ]
publicint getPreviousIndex(){ sOJ"~p
int previousIndex = getStartIndex() - |Ca$>]?
U7x}p^B9\N
pageSize; U?|s/U
if(previousIndex < 0) >Ckb9A
return0; kf5921(P
else ITbl%q
return previousIndex; 5@ZD'
} kFk+TXLDIt
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} QT%&vq
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抽象业务类 9pjk3a
java代码: m?B@VDZ
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/** M>I}^Zp!
* Created on 2005-7-12 kP;Rts8JD
*/ 7?hCt
package com.javaeye.common.business; e[e2X<&0RT
b|fq63ar;
import java.io.Serializable; Lwv9oa|
import java.util.List; j@9nX4Z
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import org.hibernate.Criteria; !4z"a@$
import org.hibernate.HibernateException; vkR"A\:
import org.hibernate.Session; s` S<BX7
import org.hibernate.criterion.DetachedCriteria; *jW$AH
import org.hibernate.criterion.Projections; }){hQt7
import =~HX/]zF
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org.springframework.orm.hibernate3.HibernateCallback; hR{Fn L
import J-,T^Wv
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org.springframework.orm.hibernate3.support.HibernateDaoS Za01z^
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upport; @ObsW!g
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import com.javaeye.common.util.PaginationSupport; Tp0Tce/
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public abstract class AbstractManager extends ~sA}.7
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HibernateDaoSupport { cc^V~-ph
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privateboolean cacheQueries = false; LTa9'
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privateString queryCacheRegion; w93yhV?
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publicvoid setCacheQueries(boolean 7qh_URt@
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cacheQueries){ 8\ :T*u3
this.cacheQueries = cacheQueries; EI f~>AI
} dB1bf2'b#
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publicvoid setQueryCacheRegion(String khEHMvVH
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queryCacheRegion){ ^Nc\D7( l
this.queryCacheRegion = i@g6%V=
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queryCacheRegion; / ?Q@Pn
} *J%+zH
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publicvoid save(finalObject entity){ .UJDn^@
getHibernateTemplate().save(entity); ~w!<J-z)
} duwZe+
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publicvoid persist(finalObject entity){ &Wn!W
getHibernateTemplate().save(entity); -aec1+o
} ,D#~%kq~
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publicvoid update(finalObject entity){ cZHlW|$R
getHibernateTemplate().update(entity); Pu}2%P)p
} aFl(K\
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publicvoid delete(finalObject entity){ 38JvJR yK}
getHibernateTemplate().delete(entity); r_Xk:
} Plt~l3_
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publicObject load(finalClass entity, ZfIQ Fh>
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finalSerializable id){ CbwQ'c$}
return getHibernateTemplate().load J/
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(entity, id); 6&h,eQ!
} ky[FNgQ3n
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publicObject get(finalClass entity, [{'` |
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finalSerializable id){ y/
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return getHibernateTemplate().get .p <!2
d)9=hp;,V
(entity, id); O-q [#P
} [9*+s
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publicList findAll(finalClass entity){ ql^n=+U
return getHibernateTemplate().find("from PYW~x@]k%,
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" + entity.getName()); [&"`2n
} /2WGo-
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publicList findByNamedQuery(finalString 1;S@XC>
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namedQuery){ Un@d Wf6'
return getHibernateTemplate arRbq!mO
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().findByNamedQuery(namedQuery); `BF +)fs
} qy/xJ>:
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publicList findByNamedQuery(finalString query, HZ )z^K?1
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finalObject parameter){ MBp%TX!
return getHibernateTemplate <Y9e n!3\
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().findByNamedQuery(query, parameter); o4\\q66K
} &r doMc;
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publicList findByNamedQuery(finalString query, Y'mtMLfMc
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finalObject[] parameters){ /&_$+Iun
return getHibernateTemplate 2V:`':
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().findByNamedQuery(query, parameters); }&F|u0@b
} fX2sjfk
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publicList find(finalString query){ <Y:{>=
return getHibernateTemplate().find P XKEqcQR
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(query); ,K
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} +DU^"q=
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publicList find(finalString query, finalObject @>cz$##`
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parameter){ u0zF::
return getHibernateTemplate().find nm Y_ )s
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(query, parameter); [;t-XC?[nk
} X6*4IE
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public PaginationSupport findPageByCriteria %PM&`c98z7
. |%n"{
(final DetachedCriteria detachedCriteria){ '
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return findPageByCriteria ti'B}bH>'
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); G!dx)v
} eu={6/O
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public PaginationSupport findPageByCriteria @QteC@k
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(final DetachedCriteria detachedCriteria, finalint ,.9k)\/V
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startIndex){ _Z7`tUS-j
return findPageByCriteria YLJ^R$pi
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(detachedCriteria, PaginationSupport.PAGESIZE, 5(>SFxz"t
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startIndex); o3]Lrzh
} 1r$*8|p
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public PaginationSupport findPageByCriteria Yw] 7@
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(final DetachedCriteria detachedCriteria, finalint Xii>?sA5Z"
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pageSize, 0civXZgj
finalint startIndex){ TyDh\f!w
return(PaginationSupport) m<H{@ZgN(
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getHibernateTemplate().execute(new HibernateCallback(){ !iO2yp
publicObject doInHibernate DA1?M' N
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(Session session)throws HibernateException { H2H`7 +I,
Criteria criteria = CYRZ2Yrk?"
_Jy7` 4B.
detachedCriteria.getExecutableCriteria(session); &&nbdu
int totalCount = &rG B58
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((Integer) criteria.setProjection(Projections.rowCount JIhEkY
/>Q}0Hg
()).uniqueResult()).intValue(); z/u^
criteria.setProjection ],_+J*
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(null); Z\?2"4H
List items = AtewC
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criteria.setFirstResult(startIndex).setMaxResults 'IG@JL'
]?pQu '-(
(pageSize).list(); |>yWkq
PaginationSupport ps = !$A/.;0$
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new PaginationSupport(items, totalCount, pageSize, }x?F53I)
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startIndex); y{S8?$dU$:
return ps; "$XX4w
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} RWc<CQcL"
}, true); -QroT`gy
} SRwD`FF
N ai5!_'
public List findAllByCriteria(final ; h\T7pwwb
,$0-I@*V
DetachedCriteria detachedCriteria){ Y8zTw`:V
return(List) getHibernateTemplate XEgJ7h_
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().execute(new HibernateCallback(){ yEq7ueJ'
publicObject doInHibernate T9C_=0(hn
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(Session session)throws HibernateException { 7
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Criteria criteria = l-Z( ]
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detachedCriteria.getExecutableCriteria(session); p&h?p\IF
return criteria.list(); d=/0A\O
} lG}#K^q
}, true); <.Ws; HN}
} ?@
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public int getCountByCriteria(final g w"
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DetachedCriteria detachedCriteria){ D7;9D*o\
Integer count = (Integer) m[^lu1\wn
q.c)>=!.
getHibernateTemplate().execute(new HibernateCallback(){ BDTL5N
publicObject doInHibernate 9 3>4n\
Ks-$:~?5":
(Session session)throws HibernateException { WwDM^}e
Criteria criteria = 5&ku]l+
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detachedCriteria.getExecutableCriteria(session); 9af.t
return T#))_aC
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criteria.setProjection(Projections.rowCount %{@Q7
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()).uniqueResult(); iRzFA!wH
} |_V(^b}
}, true); A*EOn1hN
return count.intValue();
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} U ? +_\
} DN*5q9.
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用户在web层构造查询条件detachedCriteria,和可选的 !+eH8
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 iwotEl0*{
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PaginationSupport的实例ps。 TSlB.pw%v
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ps.getItems()得到已分页好的结果集 eU[g@Pq:Y
ps.getIndexes()得到分页索引的数组 fpD$%.y'J
ps.getTotalCount()得到总结果数 "& ,ov#
ps.getStartIndex()当前分页索引 JvpGxj
ps.getNextIndex()下一页索引 cHs3:F~~
ps.getPreviousIndex()上一页索引 Ld4U
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 <ql,@*Y
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 :xd;=;q5
y&/IJst&aq
一下代码重构了。 |#oS7oV(
)@PnpC%H
我把原本我的做法也提供出来供大家讨论吧: p4`1^}f&Ie
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首先,为了实现分页查询,我封装了一个Page类: YuX JT*
java代码: Nwvlv{k'
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/*Created on 2005-4-14*/ IG781:,/
package org.flyware.util.page; 1F@k9[d~
@~3--
/** W(, j2pU
* @author Joa oQ!M+sRmF
* %TB(E<p`
*/ K\Ea\b[
publicclass Page { R><g\{G]
wQ}r/2n|^
/** imply if the page has previous page */ Z_d"<k}I
privateboolean hasPrePage; h9vcN#22D
i5,iJe0cA
/** imply if the page has next page */ NGx3f3 9
privateboolean hasNextPage; %opBJ
SQKhht`M
/** the number of every page */ Syk)S<
privateint everyPage; i"8mrWb
T]#V
/** the total page number */ nxLuzf4U5
privateint totalPage; _Nx
/<isdL
V%Uj\cv
/** the number of current page */ YOCEEh?
privateint currentPage; K1&
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'h>uR|
/** the begin index of the records by the current ajYe?z
gP^2GnjHL8
query */ ^ Ltho`
privateint beginIndex; H;H=8'
Fn4v/)*H
vOQ%f?%G\
/** The default constructor */ 80xr zv
public Page(){ \2SbW7"/;P
;b~ S/
} g:
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>oh H4:
/** construct the page by everyPage @MW@mP)#
* @param everyPage h$cm:uks
* */ ua\t5M5
public Page(int everyPage){ 4aW@c<-r?
this.everyPage = everyPage; ^t>mdxuq
} TP }a9-9?
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/** The whole constructor */ _)A|JC!jId
public Page(boolean hasPrePage, boolean hasNextPage, ~9X^3.nI
q
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int everyPage, int totalPage, tvkdNMyX%9
int currentPage, int beginIndex){ O-iE 0t
this.hasPrePage = hasPrePage; +pofN-*%
this.hasNextPage = hasNextPage; L/3A g*
]
this.everyPage = everyPage; |tXA$}"L8
this.totalPage = totalPage; RLF&-[mr3
this.currentPage = currentPage; N&9o 1_}
this.beginIndex = beginIndex; k,h602(
} v.0qE}'
|
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/** @]\fO)\f
* @return Fs+tcr/\[
* Returns the beginIndex. QX,$JM3
*/ G0FzXtu)q
publicint getBeginIndex(){ `~1!nfFD
return beginIndex; k.J%rRneN
} ]#/nn),Z
`e[S Zj\
/** 2u{~35
* @param beginIndex bR\7j+*&
* The beginIndex to set. Hv,|XE@Y
*/ Qg> NJ\*Q
publicvoid setBeginIndex(int beginIndex){ Psb !Z(
this.beginIndex = beginIndex; ggso9ZlLu+
} uvys>]+
hlVye&;b8
/** *$p*'vR
* @return J^!;$Hkd
* Returns the currentPage. 5_yQI D%Sq
*/ dFg>uo
publicint getCurrentPage(){ HC`0Ni1
return currentPage; u{1R=ML
} K_Y-N!h
-4Qub{Uym
/** d^=BXCoC
* @param currentPage >P6"-x,["
* The currentPage to set. ]8G 'R-8}
*/ I&PJ[U#~a
publicvoid setCurrentPage(int currentPage){ r>mBe;[TX
this.currentPage = currentPage; _,3ljf?WQM
} _H] \
1{uxpYAP=
/** VQ=
* @return 5Cf!NNV
* Returns the everyPage. sz7*x{E
*/ *,u3Wm|7
publicint getEveryPage(){ $QbJT`,mr
return everyPage; `kKssU<
} 7lC$UQ x8
manw;`Q
/** `IHP_IfR
* @param everyPage sG g458
* The everyPage to set. ;`AB-
*/ >a3m!`lq
publicvoid setEveryPage(int everyPage){ n,T
&n
this.everyPage = everyPage; e02Hf{eOfw
} 4KPnV+h"b
4[ uqsJB
/** 4:MvC^X~z
* @return _{|a<Keq|
* Returns the hasNextPage. k@xinK%O{
*/ c!w[)>v
publicboolean getHasNextPage(){ rzY)vC+ZT
return hasNextPage; 'h$:~C
} ?;~!C2Zs
+'F;\E
/** FgdnX2s J
* @param hasNextPage \p^V~fy7rU
* The hasNextPage to set. 5:PS74/
*/ j26i+Z
publicvoid setHasNextPage(boolean hasNextPage){ rrIyZ@_d9
this.hasNextPage = hasNextPage; Q0A4}
} Y7GsL7I
txEN7!
/** HDm]njF%qQ
* @return . _+cvXy
* Returns the hasPrePage. DJGafX^
*/ .Ys
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publicboolean getHasPrePage(){ WZa6*pF
return hasPrePage; V#G)w~
} T;M
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&M-vKc"d
/** VQIvu)I
* @param hasPrePage n7> |$2Y
* The hasPrePage to set. b'wy{~l@
*/ 9nY`rF8@
publicvoid setHasPrePage(boolean hasPrePage){ LhG\)>Y%
this.hasPrePage = hasPrePage;
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} m.++nF
_'D(>e?
/** `%YMUBaI
* @return Returns the totalPage. 9hr7+fW]t
* =r]l"T
*/ ):N#X<b':
publicint getTotalPage(){ 'Agw~
&$
return totalPage; cb-IRGF
} MkW=sD_
tE%g)hL-
/** c0wLc,)G
* @param totalPage [%k8l~ 6
* The totalPage to set. *+v*VH
*/ izSX
publicvoid setTotalPage(int totalPage){ re*Zs}(N\
this.totalPage = totalPage; <zCWLj3
} GR|\OJ<2
B=KrJ{&!
} DE.].FD'
G#[A'tbKk
,h=a+ja8
cs6oD!h
;gBR~W
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 a!R*O3
s AFn.W
个PageUtil,负责对Page对象进行构造: Kyx9_2
java代码: f2 ~Aug
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/*Created on 2005-4-14*/ h: yJ
package org.flyware.util.page; D%+yp
!aSj1
2J
import org.apache.commons.logging.Log; /KvJjt'8
import org.apache.commons.logging.LogFactory; .I_atv
ezw*Lo!
/** B*_K}5UO
* @author Joa xJZaV!N|
* p2Khfl6-
*/ Muwlehuq
publicclass PageUtil { -]wEk%j
4Q !A w
privatestaticfinal Log logger = LogFactory.getLog , >aa2
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(PageUtil.class); 5Pf=Uj6D
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/** /"J 6``MV
* Use the origin page to create a new page 6):1U
* @param page U
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* @param totalRecords %Bw:6Y4LZ
* @return 2d*bF.
*/ e1g3a1tnWl
publicstatic Page createPage(Page page, int umns*U%T;
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totalRecords){ zG$5g^J
return createPage(page.getEveryPage(), 3w)r"" C&
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page.getCurrentPage(), totalRecords); @%fTdneH
} =/K)hI!u
eP"B3Jw
/** "dP-e
* the basic page utils not including exception -TVwoK
;N#}3lpLqg
handler 9h|6"6
* @param everyPage 7d
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* @param currentPage P@PF"{S
* @param totalRecords keC'/\e
* @return page ^vMlRt;
*/ /?r A|
publicstatic Page createPage(int everyPage, int x</4/d
$F^VtCx2&
currentPage, int totalRecords){ H?O5 "4a
everyPage = getEveryPage(everyPage); t$du|q(
currentPage = getCurrentPage(currentPage); s.p>
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int beginIndex = getBeginIndex(everyPage, y5F+~z}{
7SS#V
currentPage); K ,NmDc^
int totalPage = getTotalPage(everyPage, ;[;WEA
~-Kx^3(#
totalRecords); IDn<5#
boolean hasNextPage = hasNextPage(currentPage, 9HO9>^
zHA::6OgPN
totalPage); #&T O(bk
boolean hasPrePage = hasPrePage(currentPage); \}4Y]xjV2
CPZ,sWg5
returnnew Page(hasPrePage, hasNextPage, Xuu&`U~%
everyPage, totalPage, (=uT*Cb
currentPage, P!Fykg
e4N d
beginIndex); r QiRhp
} VOD-<
"|
{ Z
k^J
privatestaticint getEveryPage(int everyPage){ )Mdddz4
return everyPage == 0 ? 10 : everyPage; /%g9g_rt#
} HSysME1X:/
6&0@k^7~
privatestaticint getCurrentPage(int currentPage){ f|VCi bI
return currentPage == 0 ? 1 : currentPage; _U&HXQ8X
} yVnG+R&
AE>W$x8P
privatestaticint getBeginIndex(int everyPage, int f$QkzWvr
c45s
#6
currentPage){ B>c$AS\5y
return(currentPage - 1) * everyPage; F}{%*EJ
} =s":Mx,o
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privatestaticint getTotalPage(int everyPage, int F$\Da)Y
g
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totalRecords){ MrB#=3pT
int totalPage = 0; !DOyOTR&3
"\EX)u9ze
if(totalRecords % everyPage == 0) 8)bR\s
totalPage = totalRecords / everyPage; >I\B_q
else N<i5X.X
totalPage = totalRecords / everyPage + 1 ; @\w}p E
7qyPI
return totalPage; y@l&B+2ks
} 0Qa0
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privatestaticboolean hasPrePage(int currentPage){ BJwuN
return currentPage == 1 ? false : true; =gI41Y]
} -B#1+rUW
tgKr*8t{
privatestaticboolean hasNextPage(int currentPage, sR1_L/.
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int totalPage){ >fWGiFmlk
return currentPage == totalPage || totalPage == Ht;Rz*}
fY9+m}$S$
0 ? false : true; 0\:=KIY.
} :W, S
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} *"WP*A\1
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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。 @CzFzVmF"
}
doAeTZ
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 *|Vf1R]
**%&|9He
做法如下: 7 2JwG7qh
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ^}Vc||S
t9U6\ru
的信息,和一个结果集List: :
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java代码: >[aR8J/U
Ztmh z_u7
`hO%(9V9
/*Created on 2005-6-13*/ /al56n
package com.adt.bo; l%2VA
Zb=NcEPGy
import java.util.List; cxs@ph&Wk
fE~KWLm
import org.flyware.util.page.Page; Gw3+TvwU+Q
Hi={(Z5tC4
/** LHA^uuBN}
* @author Joa UDr1t n
*/ 76rv$z{g^
publicclass Result { gZtQtFi
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private Page page; P^<3 Z)L
#ae?#?/"
private List content; %>Gb]dv?
.)[E`a
/** UCcr>
* The default constructor c
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*/ IW!x!~e
public Result(){ dPu27 "
super(); 9f0`HvHC
} &*OwoTgk+
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/** *d C| X
* The constructor using fields C`[2B0
* }PK4
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* @param page #a=]h}&1?
* @param content #B~;j5
*/ ;>Z+b#C[
public Result(Page page, List content){ 4A@HR
this.page = page; .t\J@?Z
this.content = content; THq}>QI
} gS<p~LPf
k_}$d{X
/** .\oW@2,RA9
* @return Returns the content. <~uzHg%Y
*/ 0J'^<GTL
publicList getContent(){ |.Vgk8oTl
return content; o(e(|k
{
} (Z>?\iNJ
9e`};DE
/** 9ad)=3A&L
* @return Returns the page. (nLzWvN
*/ @xdtl{5G
public Page getPage(){
dHx4yFS
return page; #WG}"[ ,c
} _qPKdGoM
uB"B{:Kz
/** fGV'l__\\
* @param content S Yi !%
* The content to set. 0"e["q{|
*/ MMrN#&r
public void setContent(List content){ I@m(}
this.content = content; Z#u{th
} Ec<33i]h*p
|e#W;q$v
/** O8#]7\)
* @param page :7X4VHw/
* The page to set. [O\)R[J
*/ !4cCq_
publicvoid setPage(Page page){ vUbgSI
this.page = page; ILDO/>n
} C1f$^N
} |s/Kb]t
uzQj+Po
02EX_tt),
9 D.wW
a :*N0
2. 编写业务逻辑接口,并实现它(UserManager, wq.'8Y~BE
wclj9&k
UserManagerImpl) 2|?U%YrHWs
java代码: #7 H0I8
>.UEs8QV
}8 ;,2E*z
/*Created on 2005-7-15*/ "a;$uW@.6
package com.adt.service; =4+2y '
`&x>2FJ
import net.sf.hibernate.HibernateException; ABoB=0.l
b'^<0c
import org.flyware.util.page.Page; =g6~2p=H
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import com.adt.bo.Result; *?Wz/OJ0
M3UC9t9]
/** ?r|iZKa
* @author Joa Y/UvNb<lK
*/ -}xK>
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publicinterface UserManager { zytW3sTZA
IIMf\JdM
public Result listUser(Page page)throws Z~(X[Zl
:
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HibernateException; j/oc+ M^
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} I3.JAoB>!
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3s]o~I 2x
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`yl|NL
java代码: H;a) `R3
}t(5n $go6
C+!=C{@7di
/*Created on 2005-7-15*/ B:i$
package com.adt.service.impl; IV1O/lGp
)RFY2}
import java.util.List; Ot=nKdP}D
x/]G"?Uix
import net.sf.hibernate.HibernateException; KJ&I4CU]^
mK7SEH;
import org.flyware.util.page.Page; #Q_Scxf
import org.flyware.util.page.PageUtil; Z8h;3Ek
7a_u=\,
import com.adt.bo.Result; +5O^{Ce6
import com.adt.dao.UserDAO; -{A64gfFxT
import com.adt.exception.ObjectNotFoundException; jN=
!Q&^i[
import com.adt.service.UserManager; /!5cf;kl*l
`:ZaT('h
/** LhF;A~L
* @author Joa _W Hi<,-
*/ &sn-;r
publicclass UserManagerImpl implements UserManager { X/%!p<}:'
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private UserDAO userDAO; 2b\h@VJt
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/** xG4 C 6s
* @param userDAO The userDAO to set. { .i^&
*/ Iza#v0
publicvoid setUserDAO(UserDAO userDAO){ N6\m*j,`
this.userDAO = userDAO; /i!/)]*-
} =mwAbh)[7n
u&`rK7J
/* (non-Javadoc) aY,'^S
* @see com.adt.service.UserManager#listUser bB/fU7<{)u
#Wl9[W/4
(org.flyware.util.page.Page) k'"R;^~xg
*/ tG"EbWi
public Result listUser(Page page)throws ER!s
%dd B$(
HibernateException, ObjectNotFoundException { KCa @0
int totalRecords = userDAO.getUserCount(); 6m(+X
MS
if(totalRecords == 0) {^:i}4ZRl
throw new ObjectNotFoundException LDo~
g_Y$5ft`
("userNotExist"); +4IaX1.
page = PageUtil.createPage(page, totalRecords); w2!5TKZ`
List users = userDAO.getUserByPage(page); r;waT@&C
returnnew Result(page, users); 04X/(74
} {9F}2
SJ
XGnC8Be{4
} @&E7Pg5
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cE,,9M@^
}vF=XA
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 zU|'IW&
&oVZ2.O#(
询,接下来编写UserDAO的代码: bM
W}.v!
3. UserDAO 和 UserDAOImpl: KAy uv
java代码: q+4<"b+6G
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y>J6)F
=
/*Created on 2005-7-15*/ >O1u![9K|w
package com.adt.dao; cR6#$-a
uF*tlaV6
import java.util.List; ]INt9Pvqm
J<iiA:&J
import org.flyware.util.page.Page; u69G
#
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import net.sf.hibernate.HibernateException; UPuG&A#VV
P=4o)e7E!
/** <;Td8T;
* @author Joa 'Hq#9?<2M
*/ 2DBFY1[Pk
publicinterface UserDAO extends BaseDAO { }f] ~{^
8;,(D#p
publicList getUserByName(String name)throws y
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"?
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e`
HibernateException; f5CnJhE|)
p!LaR.8]
publicint getUserCount()throws HibernateException; !V0)eC50
c#[d7t8ONe
publicList getUserByPage(Page page)throws =fK F#^E@
!?{%9
HibernateException; R|7_iMIZ
4':U rJ+
} LaIH3!M3
n]_<6{: U
"4QD\k5
G:PcV_ihx
6~8X/
-02
java代码: R8u9tTW
.|J-(J<>[.
} q r
,
/*Created on 2005-7-15*/ +&