Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 l\T!)Ql
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 J8u{K.(*7
B.}_],
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 bVa+kYE
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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 t
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分页支持类: ,?xLT2>J_
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java代码: ,]PyDq6
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package com.javaeye.common.util; E ;BPN
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import java.util.List; _KB{J7bs<a
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publicclass PaginationSupport { }J ei$0x
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publicfinalstaticint PAGESIZE = 30; W>5vRwx00
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privateint pageSize = PAGESIZE; e2]4a3
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privateList items; |^7f\.oF
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privateint totalCount; ADv^eJJ|
u* t,i`
privateint[] indexes = newint[0]; NJ;"jQ-
8
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privateint startIndex = 0; jd%Len&p
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public PaginationSupport(List items, int up\oWR:
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totalCount){ Awu$g.
setPageSize(PAGESIZE); S~@r
setTotalCount(totalCount);
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setItems(items); O1GDugZ
setStartIndex(0); ~L-0~
} A}t %;V2
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public PaginationSupport(List items, int [##`Um
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totalCount, int startIndex){ YBb)/ZghY
setPageSize(PAGESIZE); 0HGl f
setTotalCount(totalCount); [8>z#*B
setItems(items);
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setStartIndex(startIndex); :83,[;GO2
} FJP< bREQ
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public PaginationSupport(List items, int )v[XmJ>H~o
8F#osN
totalCount, int pageSize, int startIndex){ j|:dYt`WM
setPageSize(pageSize); IByf_E;r
setTotalCount(totalCount); _fcS>/<a
setItems(items); "j{i,&Y$_
setStartIndex(startIndex); >_XOc
} `NBbTQtgO
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publicList getItems(){ QX[Djz0H8
return items; `/#f?Hk=
} WfTD7?\dw
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publicvoid setItems(List items){ \)ip>{WG
this.items = items; )uZoH8?
} #
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publicint getPageSize(){ Z&_y0W=t
return pageSize; 4&Byl85q
} lC0~c=?J
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publicvoid setPageSize(int pageSize){ U^MuZ
this.pageSize = pageSize; $@_{p*q
} 4SgF,ac3r
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publicint getTotalCount(){ I%oRvg|q
return totalCount; |,b2b2v?
} zj<ahg%z
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publicvoid setTotalCount(int totalCount){ "!O1j
r;
if(totalCount > 0){ |^R*4;Phe
this.totalCount = totalCount; bmu6@jT
int count = totalCount / L>dkrr)e
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pageSize; Hkdf $$\
if(totalCount % pageSize > 0) B`fH^N
count++;
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indexes = newint[count]; x?#I4RJH;
for(int i = 0; i < count; i++){ *ZaaO^!
indexes = pageSize * GcT;e5D
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i; Gqb])gXpl
} ]4`t\YaT
}else{ ;B~P>n}}_]
this.totalCount = 0; mzX;s&N#
} 'BY-OA#xJ
} ?~J i-{#X
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publicint[] getIndexes(){ En(7(qP6}
return indexes; B{C_hy-fw
} ^T:gb]i'Qa
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publicvoid setIndexes(int[] indexes){ DECB*9O^
this.indexes = indexes; xACdZB(
} Rf)ke("
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publicint getStartIndex(){ !^e =P%S
return startIndex; 'cV?i&;
} yhpz5[AuO
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publicvoid setStartIndex(int startIndex){ /.Fj.6U5
if(totalCount <= 0) _%~$'Hy
this.startIndex = 0; 54{q.I@n
elseif(startIndex >= totalCount) +`B'r
'
this.startIndex = indexes 3uV4/%U
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[indexes.length - 1]; 8Hi!kc;f6>
elseif(startIndex < 0) ^rL_C}YBj-
this.startIndex = 0; %y&]'A
else{ EF#QH
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this.startIndex = indexes 87V1#U ^
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[startIndex / pageSize]; {hQ6K)s
} I9Eu',
} & ze>X
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publicint getNextIndex(){ 9@K.cdRjQ
int nextIndex = getStartIndex() + .$&Q[r3Lu
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pageSize; G,XPT,:%
if(nextIndex >= totalCount) d;7uFh|o
return getStartIndex(); m}3gZu]
else s
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return nextIndex; ?<U{{C
} =Q<L
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publicint getPreviousIndex(){ v.=/Y(J
int previousIndex = getStartIndex() - h1[WhBL-O
QJn`WSw$_-
pageSize; DWU`\9xA*
if(previousIndex < 0) ffe1lw%
return0; fY,|o3#
else >Kivuc
return previousIndex; =8Ehrlq
} }tG3tz0%fX
2&Jdf
} }7s>B24J
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抽象业务类 9zBMlc$X
java代码:
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/** VsK>6S\T
* Created on 2005-7-12 a|4~NL
*/ C/=XuKE-t
package com.javaeye.common.business; amWD-0V
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import java.io.Serializable; l@JSK;
import java.util.List; ]Mi.f3QlO6
h3*
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import org.hibernate.Criteria; \4d.sy0&>-
import org.hibernate.HibernateException; .8WXC
import org.hibernate.Session; ({^9<Us
import org.hibernate.criterion.DetachedCriteria; e>}}:Ud
import org.hibernate.criterion.Projections; (`BSVxJH
import Q`%R[#
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org.springframework.orm.hibernate3.HibernateCallback; g(C|!}ex/
import |X19fgk
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org.springframework.orm.hibernate3.support.HibernateDaoS (u3s"I
d
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upport; 2@=IT0[E\
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import com.javaeye.common.util.PaginationSupport; hm*cw[#O1x
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public abstract class AbstractManager extends 69K{+|
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HibernateDaoSupport { N|g;W
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privateboolean cacheQueries = false; kq=V4-a[
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privateString queryCacheRegion; a:,y
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publicvoid setCacheQueries(boolean )D&M2CUw"f
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cacheQueries){ !4"^`ors$
this.cacheQueries = cacheQueries; U69u'G:
} :O<bA&:d
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publicvoid setQueryCacheRegion(String d[ >`")2)
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queryCacheRegion){ %+>s#Q2d
this.queryCacheRegion = %xZG*2vc!B
p?D2)(
queryCacheRegion; <*!i$(gn
} $2^`Uca
+ @9.$6N
publicvoid save(finalObject entity){ &,\=3'
getHibernateTemplate().save(entity); V
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} N,dT3we
M 3 '$[
publicvoid persist(finalObject entity){ '_\;jFAM
getHibernateTemplate().save(entity); $''?HjB}T
} }9HmTr|
{`=0 |oP}
publicvoid update(finalObject entity){ K,'*Dz
getHibernateTemplate().update(entity); cJo\#cr
} %@a8P
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publicvoid delete(finalObject entity){ F~:O.$f]G
getHibernateTemplate().delete(entity); ?3ig)J,e[
} :2
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publicObject load(finalClass entity, '>$EOg"
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finalSerializable id){ `afIYXP
return getHibernateTemplate().load U[L9*=P;
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(entity, id); VErv;GyV
} Q|Y0,1eVp|
7!,YNy%
publicObject get(finalClass entity, Aa0b6?Jm
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finalSerializable id){ FLg*R/
return getHibernateTemplate().get Z/x*Y#0@n
f<=Fsl
(entity, id); ;*ix~taL%
} '7wd$rl
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publicList findAll(finalClass entity){ )VL96 did
return getHibernateTemplate().find("from !Fo*e
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" + entity.getName()); <IW#ME
} D jk C
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publicList findByNamedQuery(finalString 2%*MW"Q
] Z8Vj7~
namedQuery){ b2 _Yu^
return getHibernateTemplate Sxdsv9w
p4IZ
().findByNamedQuery(namedQuery); MuoF FvAA
} g%F"l2M
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publicList findByNamedQuery(finalString query, X[#zCM
M/x >51<
finalObject parameter){ ^7;JC7qmN
return getHibernateTemplate P%)gO
5@*'2rO&!
().findByNamedQuery(query, parameter); <YA&Dr3OD
} (~zd6C1.
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publicList findByNamedQuery(finalString query, m9U"[Huv1E
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finalObject[] parameters){ q$1PG+-
return getHibernateTemplate ]yjl~3
9/+Nj /
().findByNamedQuery(query, parameters); :o:e,WKxb
} $^u}a
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publicList find(finalString query){ UobyK3.%
return getHibernateTemplate().find 2G$SpfeIu
pg]BsJN
(query); ,-x!$VqS
} OD']:
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publicList find(finalString query, finalObject tXJUvish
BCe_@
parameter){ aP'"G^F
return getHibernateTemplate().find ARcv;H 5
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(query, parameter); u77E! z4Uz
} XLMb=T~S
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public PaginationSupport findPageByCriteria Ax !+P\\2~
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(final DetachedCriteria detachedCriteria){ VqL.iZ-
return findPageByCriteria +[SgO}sF
2pdvWWh3l
(detachedCriteria, PaginationSupport.PAGESIZE, 0); .>z][2oz
} eIl]oC7*
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public PaginationSupport findPageByCriteria XZw6Xtn
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(final DetachedCriteria detachedCriteria, finalint ]|<w\\^A
Xl@cHO=i
startIndex){ AoA!q>
return findPageByCriteria WyP W*
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(detachedCriteria, PaginationSupport.PAGESIZE, ~=R SKyzt
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startIndex); ]*7Y~dO
} EUsI%p
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public PaginationSupport findPageByCriteria ?FfC
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(final DetachedCriteria detachedCriteria, finalint ie-vqLc
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pageSize, r>GZ58i
finalint startIndex){ #+$Q+Z|6k
return(PaginationSupport) v&Kqq!DE
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getHibernateTemplate().execute(new HibernateCallback(){ =@F&o4) r
publicObject doInHibernate r-,e;o>9
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(Session session)throws HibernateException { 0ZQ' _g|%
Criteria criteria = ko5V9Drc
[]s^
detachedCriteria.getExecutableCriteria(session); l }XU59
int totalCount = ja=F 7Usb
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((Integer) criteria.setProjection(Projections.rowCount G%d
(
ioPUUUb)
()).uniqueResult()).intValue(); yoAfc
criteria.setProjection |p$spQ
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(null); >vo=]cw
List items = y\{%\ $
ax
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criteria.setFirstResult(startIndex).setMaxResults DNP13wp@
.jMq
(pageSize).list(); A<;SnXm
PaginationSupport ps = JI vo_7{
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new PaginationSupport(items, totalCount, pageSize, FZ8b7nJ)4m
|>z3E z
startIndex); G9JAcO1
return ps; b%cF
} 1yqJwy;X
}, true); oPPX&e@=s]
} =_0UD{"_0
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public List findAllByCriteria(final ;NlWb =
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DetachedCriteria detachedCriteria){ /r_~:3F
return(List) getHibernateTemplate H.UX,O@
n("0%@ov
().execute(new HibernateCallback(){ " LJq%E
publicObject doInHibernate XkyKBg-
IUtx!.]4
(Session session)throws HibernateException { >ooZj9:'
Criteria criteria = ;NRF=d>
vB+ '
detachedCriteria.getExecutableCriteria(session); .CFa9"<
return criteria.list(); Ao/ jt<
} |g*XK6
}, true); ;qBu4'C)T
} 4 {9B9={
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public int getCountByCriteria(final |\n_OS7
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DetachedCriteria detachedCriteria){ \(%Y%?dy
Integer count = (Integer) '? jlH0;
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getHibernateTemplate().execute(new HibernateCallback(){ |.wEm;Bz
publicObject doInHibernate H'HSD,>(
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(Session session)throws HibernateException { ]n-:Yv5 W
Criteria criteria = o: ;"w"G
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detachedCriteria.getExecutableCriteria(session); MMj9{ou
return ,*7d
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criteria.setProjection(Projections.rowCount wd)jl%
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()).uniqueResult(); <\;#jF%V
} o;?/HE%,[
}, true); 85GKymz$P
return count.intValue(); MQ"xOcD*F
} +5XpzZ{#Wa
} /B}lO0]:
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用户在web层构造查询条件detachedCriteria,和可选的 H#ncM~y*
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 P@FHnh3}Z$
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PaginationSupport的实例ps。 AFAAuFE"
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ps.getItems()得到已分页好的结果集 $LU"?aAW
ps.getIndexes()得到分页索引的数组 v,ju!I0.
ps.getTotalCount()得到总结果数 F+u|HiYG
ps.getStartIndex()当前分页索引 9:M`
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ps.getNextIndex()下一页索引 ^_m9KA
ps.getPreviousIndex()上一页索引 YY!Rz[/
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 8w.YYo8`
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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 =AuR:Tx
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一下代码重构了。 Sy
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我把原本我的做法也提供出来供大家讨论吧: G["c\Xux
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首先,为了实现分页查询,我封装了一个Page类: Ih"XV
java代码: cCxBzkH6
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/*Created on 2005-4-14*/ Er{>p|n=
package org.flyware.util.page; S;-
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/** >qF CB\(
* @author Joa ^-
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* sQ\8>[]
*/ *Em,*!
publicclass Page { ^N)R=tl
gdQvp=v]
/** imply if the page has previous page */ zO iu5
privateboolean hasPrePage; 1Yn
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/** imply if the page has next page */ Pjc
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privateboolean hasNextPage; .qZI$
l.
f=9|b
/** the number of every page */ qXwPDq/
privateint everyPage; &mx)~J^m
pS7w' H
/** the total page number */ Bf8jPa/
privateint totalPage; v%iflCK
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/** the number of current page */ @qYp>|AF
privateint currentPage; [;J>bi;3N
@
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/** the begin index of the records by the current %B.yW`,X
HKUn`ng
query */ b"{'T]"*j
privateint beginIndex; N=7pK&NHSG
k-^mIJo}
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/** The default constructor */ :w^Ed%>y7
public Page(){ ,JQp'e
]'=)2
.}
} W}mn}gTQ
>: g3k
/** construct the page by everyPage R)m'lMi|
* @param everyPage \r+8qC[,
* */ +O?KNZ
public Page(int everyPage){ 7](KV" %V
this.everyPage = everyPage; Xx>X5Fy
} OL^l 3F
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/** The whole constructor */ @W"KVPd
public Page(boolean hasPrePage, boolean hasNextPage, z+n,uHs
Jh!I:;/
)`(p9@,V
int everyPage, int totalPage, #$8% w
int currentPage, int beginIndex){ ",KCCis
this.hasPrePage = hasPrePage; @y\XR
this.hasNextPage = hasNextPage; i=oU;7~zK
this.everyPage = everyPage; 5lUF7:A>#
this.totalPage = totalPage; %#xaA'?
[
this.currentPage = currentPage; 2$ze=
/ l
this.beginIndex = beginIndex; 9~/J35
} <"my^
R[hzMU}KB
/** 4J/}]Dr5
* @return 7\ s"o&G
* Returns the beginIndex. ?b>,9A.Z
*/ IHv[v*4:
publicint getBeginIndex(){ 9^#c|
0T
return beginIndex; 7%|~>
} 6"&6`f
"ozr+:#\
/** t^G"f;Ra+
* @param beginIndex cmU1!2.1E
* The beginIndex to set. 1oWED*B
*/ `ux{;4q
publicvoid setBeginIndex(int beginIndex){ 0?:} P
this.beginIndex = beginIndex; {ix?Brq/
} 9 %I?).5
r
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/** FW G6uKv
* @return CU@Rob} s
* Returns the currentPage. ?FpWvyz|
*/ 67G?K;)e
publicint getCurrentPage(){ Zy?Hi`
return currentPage; l:,'j@%
} ?!d&E?9\
E^/t$M|H
/** 'O_3)x5
* @param currentPage !C3MFm{B
* The currentPage to set. |es?;s'
*/ PuA9X[=
publicvoid setCurrentPage(int currentPage){ K1+)4!}%U
this.currentPage = currentPage; TE7nJ gm
} L>aLqQ3
YSic-6z0Ms
/** lJ}_G>GJ
* @return %Q
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* Returns the everyPage. ogHCt{'
*/ F`XP@Xx
publicint getEveryPage(){ "8x8UgG
return everyPage; iXVe.n
} 1AM!8VR2
*U,@q4
/** :*Z4yx
* @param everyPage 4gz
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* The everyPage to set. K<SyC54
*/ ( u\._Gwsx
publicvoid setEveryPage(int everyPage){ %InA+5s`
this.everyPage = everyPage; c4^ks&)'
} g"p%C:NN
4~Vx3gEV:
/** i]YV {
* @return 7byK{{/z
* Returns the hasNextPage. `(ue63AZ
*/ ~obqG!2m
publicboolean getHasNextPage(){ "$+Jnc!!
return hasNextPage; lm-dW'7&
} P3x= 8_#
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/** diL+:H
* @param hasNextPage 1{ ~#H<K
* The hasNextPage to set. p.v0D:@&
*/ Q kEvw<
publicvoid setHasNextPage(boolean hasNextPage){ )NXmn95
this.hasNextPage = hasNextPage; tl,.fjZn
} =[cS0Sy
(|:M&Cna]
/** vNV/eB8#S
* @return pfA|I*`XV
* Returns the hasPrePage. v&Yi
*/ Ai=se2
publicboolean getHasPrePage(){ Pq;U&,
return hasPrePage; )wam8k5
} fTS5yb%
*'.|9W
/** `scR*]f1+
* @param hasPrePage #~}nFY.
* The hasPrePage to set. Wuc S:8#|
*/ ZM!CaR
publicvoid setHasPrePage(boolean hasPrePage){ 9kN}c<o
this.hasPrePage = hasPrePage; B(LWdap~
} ~:kZgUP_f
42{Ew8
/** m ZtCL
* @return Returns the totalPage. #%iDT6
* vj'wm}/
*/ : UGZ+
publicint getTotalPage(){ Bu<M\w?7Y
return totalPage; ;4R$g5-4X
} wSzv|\
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/** ]HKQDc'
* @param totalPage c}Ft^Il
* The totalPage to set. OE_XCZ!5P
*/ S!jTyY7e
publicvoid setTotalPage(int totalPage){ 1an^1!
this.totalPage = totalPage; H[s(e56z
} 8ndYV>{f
BZ94NOOdw
} fxgPhnaC>
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#C~+JL
c]x1HvPE
jSD#X3qp
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 aktU$Wbwl
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个PageUtil,负责对Page对象进行构造: iV5yJF{ZH
java代码: lP[w?O
ocqU=^ta
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/*Created on 2005-4-14*/ 8{wwd:6
package org.flyware.util.page; 9oRy)_5Z(=
/[a~3^Gs^
import org.apache.commons.logging.Log; q.KG^=10
import org.apache.commons.logging.LogFactory; 6Z>FTz_
SN9kFFIPb=
/** 3EV;LH L
* @author Joa CY
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* y6ECdVF
*/ 7,U=Qe;
publicclass PageUtil { IpINH3odT
%q/62f7?
privatestaticfinal Log logger = LogFactory.getLog V/%>4GYnC
oibsh(J3
(PageUtil.class); oI0M%/aM
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/** s`M9
* Use the origin page to create a new page aXQnZ+2e^R
* @param page d?s<2RkPT
* @param totalRecords ~ZmN44?R
* @return ;X8yFq
*/ EY^1Y3D w0
publicstatic Page createPage(Page page, int opY@RJ]
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totalRecords){ kW2sY^Rg
return createPage(page.getEveryPage(), N+m)/x
=:
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page.getCurrentPage(), totalRecords); 3C?f(J}
} xHUsFms
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/** Pj#<K%Bz
* the basic page utils not including exception Gy9$wH@8
]mo-rhDsM
handler eK6hS_E
* @param everyPage |8&,b`Gfo
* @param currentPage :Ux?,
* @param totalRecords Qiua
* @return page V@B__`y7
*/ -|J"s$yO4
publicstatic Page createPage(int everyPage, int HKU~UTRnZ
nim*/LC[:
currentPage, int totalRecords){ %z/hf
everyPage = getEveryPage(everyPage); ~k\fhx
currentPage = getCurrentPage(currentPage); zjJ *n8l
int beginIndex = getBeginIndex(everyPage, 9E
zj"
j5K]CTz#
currentPage); Hc!
mB
int totalPage = getTotalPage(everyPage, B( ]M&
txJr;
totalRecords); 8e*,jH3
boolean hasNextPage = hasNextPage(currentPage, @XgKYm
w zYzug
totalPage); 7FzA*
boolean hasPrePage = hasPrePage(currentPage); Of-Rx/
p6]7&{>
returnnew Page(hasPrePage, hasNextPage, xO$lsZPG
everyPage, totalPage, $:cE ^8K
currentPage, tR}MrM
I~q#eO)
beginIndex); r;/4F/6"
} c2h{6;bfY
&qMPq->
privatestaticint getEveryPage(int everyPage){ M2HomO/X)
return everyPage == 0 ? 10 : everyPage; iWRH{mK
} $h5xH9x
;
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privatestaticint getCurrentPage(int currentPage){ t0/p]=+.p/
return currentPage == 0 ? 1 : currentPage; XF P atd
}
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privatestaticint getBeginIndex(int everyPage, int ~o82uw?
~c8?>oN(
currentPage){ @E^~$-J5j
return(currentPage - 1) * everyPage; ~;QvWS
} o]+z)5zC
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privatestaticint getTotalPage(int everyPage, int J{l1nHQZSu
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totalRecords){ e&simX;W
int totalPage = 0; *v;!-F&8>
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if(totalRecords % everyPage == 0) n1qQ+(xC
totalPage = totalRecords / everyPage; 03xa'Of>
else H9KKed47d/
totalPage = totalRecords / everyPage + 1 ; N8!cO[3Oh
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return totalPage; %u`8minCt
} J1/?JfF
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privatestaticboolean hasPrePage(int currentPage){ #,S0HDDHn
return currentPage == 1 ? false : true; Tu@8}C
} ;lq;X{/
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privatestaticboolean hasNextPage(int currentPage, BS /G("oZ[
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int totalPage){ il}%7b-
return currentPage == totalPage || totalPage == <DMl<KZ
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9}
0 ? false : true; *Nw&_<\9Q
} /+8JCp
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} #%`|~%`{:
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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。 &yGaCq;0
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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 _ 6O\W%it
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做法如下: L>MLi3{
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ,RE\$~`w
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的信息,和一个结果集List: ^w(p8G_-w
java代码: eKgisY4#
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/*Created on 2005-6-13*/ (>F%UY
package com.adt.bo; pR
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import java.util.List; C2@,BCR
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import org.flyware.util.page.Page; =6woWlf b
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/** 4?0vso*X<:
* @author Joa ">~.$Jp_4
*/ 7Ok;Lt!x
publicclass Result { 2}YOcnB
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private Page page; aT_&x@x
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private List content; KQacoUHrK?
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/** 7+]=-
* The default constructor `^bgUmJ~
*/ D-8O+.@
public Result(){ 6WV\}d:
super(); GMMp|WV|
} +hn+K1
@b"t]#V(E
/** ZPiq-q
* The constructor using fields }MRd@ 0-?!
* MHSs!^/g5
* @param page tYZ[68
* @param content }Mo=PWI1?
*/ @|<<H3I
public Result(Page page, List content){ :{qv~&+C
this.page = page; ~vs}.kb
this.content = content; QF{4/y^j{
} %{YN70/
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/** [`p=(/I&L
* @return Returns the content. MxWy*|J}
*/ bSsh^Z
publicList getContent(){ ~7Ts_:E-
return content; f>aEkh6u9
} jZh';M8"
;FBUwR}
/** 0|2%vh >J
* @return Returns the page. $wmvKQc{lx
*/ uIcn{RZ_z
public Page getPage(){ A'G66ei
return page; n3}!p'-CC
} CK:y?
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/** T_sTC)&a
* @param content :/:.Kb
* The content to set. 8aO~/i:(.
*/ s_x:T<]
public void setContent(List content){ GKvN*
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this.content = content; qY~`8
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} =0^Ruh
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/** j{Hao\F8
* @param page Ul2R'"FB
* The page to set. d*A*y ^OD
*/ la( <8
publicvoid setPage(Page page){ T32+3wb"I
this.page = page; gN24M3{C
} '3TW [!m
} f@8>HCI
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2. 编写业务逻辑接口,并实现它(UserManager, b7 !Qn}
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UserManagerImpl) 6b%WHLUeT
java代码: ^xh}I5
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/*Created on 2005-7-15*/ 9so6WIWc
package com.adt.service; <Ard7UT
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import net.sf.hibernate.HibernateException; B*4}GPQ
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import org.flyware.util.page.Page; ?_"+^R z
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import com.adt.bo.Result; 0G7K8`a
>=UF-xk;
/** w=LP"bqlI
* @author Joa _^el\
*/ tjGd )
publicinterface UserManager { OR}c)|1
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public Result listUser(Page page)throws PZ{Dv'C
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HibernateException; FDVcow*] n
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} w=^`w:5X
w QNxL5B
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java代码: Kv.>Vf.T}_
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q4}PM[K?=\
/*Created on 2005-7-15*/ Qtbbb3m;
package com.adt.service.impl; Ku\Y'ub
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import java.util.List; +n<k)E@>J
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import net.sf.hibernate.HibernateException; R2(3>`FJ
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import org.flyware.util.page.Page; UJfEC0
import org.flyware.util.page.PageUtil; YqPQ%
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import com.adt.bo.Result; x~GQV^(l3
import com.adt.dao.UserDAO; {"&SJt[%X
import com.adt.exception.ObjectNotFoundException; /1x,h"T\<
import com.adt.service.UserManager; 'XzXZJ[uq
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/** 5aln>1x>hn
* @author Joa %^1cyk
*/ ,WvY$_#xW%
publicclass UserManagerImpl implements UserManager { <Q?a=4
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private UserDAO userDAO; bYi`R)
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/** &Y
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* @param userDAO The userDAO to set. ^5A
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*/ 'ihhoW8
publicvoid setUserDAO(UserDAO userDAO){ Qu}W/j|3
this.userDAO = userDAO; 1Wm)rXW[x
} *+uHQgn(
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/* (non-Javadoc) P>sFV
* @see com.adt.service.UserManager#listUser +T=(6dr
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(org.flyware.util.page.Page) z]2]XTmWs
*/ i&vaeP25)
public Result listUser(Page page)throws v.:3"<ur}
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HibernateException, ObjectNotFoundException { )$`wIp
int totalRecords = userDAO.getUserCount(); [@Q_(LQ-U
if(totalRecords == 0) -
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throw new ObjectNotFoundException }|5VRJA
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("userNotExist"); e.@uhB.
page = PageUtil.createPage(page, totalRecords); `.T}=j|
List users = userDAO.getUserByPage(page); 8}fu,$$5
returnnew Result(page, users); #
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} Qt,M!i,
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} n+BJxu?
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 K"b`#xN(t
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询,接下来编写UserDAO的代码: Yr w$
3. UserDAO 和 UserDAOImpl: rp6q?3=g
java代码: j6
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/*Created on 2005-7-15*/ $&"V^@
package com.adt.dao; Ndo a4L)$
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import java.util.List; zfc3)7
f]G>(V=i
import org.flyware.util.page.Page; lj{VL}R
o/C\d$i'
import net.sf.hibernate.HibernateException; {q<03d~9|G
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/** 2-"0 ^n{
* @author Joa ;U<rc'qE
*/ Iw<j T|y)
publicinterface UserDAO extends BaseDAO { @^;j)%F}
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publicList getUserByName(String name)throws w|CZ7|6
sTOa
HibernateException; Qb!PRCHQ
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publicint getUserCount()throws HibernateException; DhX#E&
}g3+{\x8
publicList getUserByPage(Page page)throws 01T`Flz
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HibernateException; fZxIY,
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} v^ /Q 8Q
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java代码: 6Z`R#d #I
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/*Created on 2005-7-15*/ <5G{"U+ \
package com.adt.dao.impl; .`7cBsXH
d/}SAvtt
import java.util.List; 8/t$d#xHI
h'$QC )P
import org.flyware.util.page.Page; rJa$9B*^
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import net.sf.hibernate.HibernateException; xil[#W]7Ge
import net.sf.hibernate.Query; 9}c8Xt^&