Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 u*@R`,Y
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 QWOPCoUet
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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 ch8VJ^%Ra1
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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 cIw X sx
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分页支持类: &b#d4p6&l
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java代码: mj'~-$5T
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package com.javaeye.common.util; qkhre3
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import java.util.List; eWDXV-xD
@}4>:\es
publicclass PaginationSupport { v,}C~L3
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publicfinalstaticint PAGESIZE = 30; +zMhA p
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privateint pageSize = PAGESIZE; GPHb-
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privateList items; i[KXkjr
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privateint totalCount; V|
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privateint[] indexes = newint[0]; q.=Q
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privateint startIndex = 0; "~ID.G|<
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public PaginationSupport(List items, int /}@F
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totalCount){ VvW4!1Dl
setPageSize(PAGESIZE); \YzKEYx+
setTotalCount(totalCount); : 2%eh
setItems(items); :(XyiF<Ud
setStartIndex(0); TQO|C?
} 5b"=m9{g
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8w
public PaginationSupport(List items, int [l^XqD D4
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totalCount, int startIndex){ 4|_xz;i
setPageSize(PAGESIZE); q,ie)`
setTotalCount(totalCount); <2]h$53y!
setItems(items); CCG5:xS
setStartIndex(startIndex); fh`Y2s|:7R
} Mk#r_:[BS
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public PaginationSupport(List items, int "}_J"%
= "]r{
totalCount, int pageSize, int startIndex){ 1L::Qu%E
setPageSize(pageSize); :.AC%'S
setTotalCount(totalCount); 3Y#
setItems(items); WILa8"M
setStartIndex(startIndex); f.J^HQ_
} |I1,9ex
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publicList getItems(){ O83J[YuzjN
return items; K7C
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} k+{~#@
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publicvoid setItems(List items){ :i>LESJq
this.items = items; #tZ!D^GQHq
} 5*2hTM!
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publicint getPageSize(){ 8US35t:M
return pageSize; Gs"lmX-{$j
} |rJN
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publicvoid setPageSize(int pageSize){ :a Cf@:']
this.pageSize = pageSize; 9K}DmS
} fASklcQ
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publicint getTotalCount(){ Q#yHH]U)X
return totalCount; 1^o})9
} 2n>mISy+
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.DR
publicvoid setTotalCount(int totalCount){ fV4eGIR&
if(totalCount > 0){ P\ P=1NM
this.totalCount = totalCount; =?Ry,^=b
int count = totalCount / *H/)S 5
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pageSize; XC6 |<pru
if(totalCount % pageSize > 0) I;jH'._k#
count++; br88b`L
indexes = newint[count]; P}AwE,&Q
for(int i = 0; i < count; i++){ JGq9RB]D$
indexes = pageSize * @8J*vY =e
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i; Ke^/aGi}O
} IrRy1][Qr
}else{ "T /$K
this.totalCount = 0; y+B iaD!U
} 9*j"@Rm
} tPiC?=4R
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publicint[] getIndexes(){ "xC$Ko _
return indexes; 3U?gw!M>
} W!el[@
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publicvoid setIndexes(int[] indexes){ 7mnO60Z8N
this.indexes = indexes; Se??E+aX
} )LG!"~qiz
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publicint getStartIndex(){ -"Kjn`8
return startIndex; 71(ppsHk
} CA|W4f}
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publicvoid setStartIndex(int startIndex){ G@rh/b<$
if(totalCount <= 0) [D|Uwq
this.startIndex = 0; 3J4OkwqD
elseif(startIndex >= totalCount) uAYDX<Ja9
this.startIndex = indexes 0Q>
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[indexes.length - 1]; :p<:0W2!
elseif(startIndex < 0) BpFXe7
this.startIndex = 0; ^,'KmZm=
else{ s#8}&2#l
this.startIndex = indexes y1Br4K5C
kazgI>"Q8
[startIndex / pageSize]; }nM+"(}
} Wf:X)S7
} "JF
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publicint getNextIndex(){ :ldI1*@i<
int nextIndex = getStartIndex() + 3KD:JKn^
sFfargl
pageSize; \SmYxdU'>
if(nextIndex >= totalCount) <vg|8-,#m
return getStartIndex(); V:D?i#%,z
else ,!AYeVq
return nextIndex; 5#_GuL%
} V+'zuX
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publicint getPreviousIndex(){ _B4N2t$
int previousIndex = getStartIndex() - L eUp!
t P'._0n0
pageSize; *Q-uE
if(previousIndex < 0) H5FWk
return0; S2I{?y&K
else >r:z`^p
return previousIndex; 4[r:DM|8
} nm|"9|/
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} s?sr0HZ
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抽象业务类 0rDQJCm
java代码: <aMihT)dd
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/** =6'D/| 3
* Created on 2005-7-12 $xcU*?=K
*/ %E":Wv
package com.javaeye.common.business; ac43d`wpK
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import java.io.Serializable; @`sZV8
import java.util.List; z[+pN:47
A{eh$Ot%
import org.hibernate.Criteria; 7BgA+Fz
import org.hibernate.HibernateException; QUdF`_U7
import org.hibernate.Session; u"q!p5P%q
import org.hibernate.criterion.DetachedCriteria; Qz A)HDQ
import org.hibernate.criterion.Projections; f,+ONV]5Tt
import (aq^\#9btO
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org.springframework.orm.hibernate3.HibernateCallback; L#T`h}1Z
import 6:bvq?5a5
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org.springframework.orm.hibernate3.support.HibernateDaoS Zg;Ht
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upport; Wf
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import com.javaeye.common.util.PaginationSupport; `t#Ie*
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public abstract class AbstractManager extends @aoHz8K
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HibernateDaoSupport { {<^PYN>`
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privateboolean cacheQueries = false; 4d]T`
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privateString queryCacheRegion; rI1;>/Ir
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publicvoid setCacheQueries(boolean JA?P jo
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cacheQueries){ ~u80v h'
this.cacheQueries = cacheQueries; [~rBnzb
} @|o^]-,
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publicvoid setQueryCacheRegion(String dLu3C-.(
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queryCacheRegion){ ]?2&d[
this.queryCacheRegion = S|v-lJ/I
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queryCacheRegion; ki_Py5
} }~ o>H a;
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publicvoid save(finalObject entity){ /&'rQ`nd
getHibernateTemplate().save(entity); cd*F;h
} L
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publicvoid persist(finalObject entity){ wkZ}o,{*:
getHibernateTemplate().save(entity); 8:0.Pi(ln@
} 9Lxa?Y1
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publicvoid update(finalObject entity){ KbF,jm5
getHibernateTemplate().update(entity); d\aU rsPn
} !xh.S#B
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publicvoid delete(finalObject entity){ 2f@gR9T
getHibernateTemplate().delete(entity); JS1''^G&.
} fNaS?tV)
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publicObject load(finalClass entity, fqU*y 6]
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finalSerializable id){ 7L&=z$U@m
return getHibernateTemplate().load N)Z,/w9
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(entity, id); wrW768WR
} b]U%|bp
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publicObject get(finalClass entity, cO
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finalSerializable id){ Li_ a|dI
return getHibernateTemplate().get 0dgp<
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(entity, id); 3 aG?^z
} g&V1<n\b+
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publicList findAll(finalClass entity){ H{CG/+x
return getHibernateTemplate().find("from E7qk>~Dg
,0=:06l
" + entity.getName()); "+V.Yue`R
} @'EU\Y\l
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publicList findByNamedQuery(finalString Am?
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namedQuery){ `PR)7}/<
return getHibernateTemplate aJ1<X8
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().findByNamedQuery(namedQuery); />zE$)'M
} PN n{Rt
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publicList findByNamedQuery(finalString query, D?3^>h
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finalObject parameter){ }?=$?3W
return getHibernateTemplate 4b B)t#
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().findByNamedQuery(query, parameter); -%lA=pS{Fq
} fE;<)tU
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publicList findByNamedQuery(finalString query, @exeHcW61
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finalObject[] parameters){ j ,'$i[F'
return getHibernateTemplate xFt[:G`\}u
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().findByNamedQuery(query, parameters); ((}T^
} 3U0>Y%m| ,
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publicList find(finalString query){ ) )q4Rh
return getHibernateTemplate().find [kIiKLX
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(query); Y9)uy 8c
} 6.| {l8%r
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publicList find(finalString query, finalObject 0?KY9
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parameter){ RG9YA&1ce
return getHibernateTemplate().find %- W3F5NK
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(query, parameter); ab5 a>w6}
} }j^asuf~c
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public PaginationSupport findPageByCriteria I'Dc9&2
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(final DetachedCriteria detachedCriteria){ x w8
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return findPageByCriteria X!,2/WT
;by`[)
(detachedCriteria, PaginationSupport.PAGESIZE, 0); fz[o;GTc
} !e5!8z
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public PaginationSupport findPageByCriteria 038|>l-9[
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(final DetachedCriteria detachedCriteria, finalint B|9)4f&\=R
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startIndex){ N8!V%i?
return findPageByCriteria ,%>]
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(detachedCriteria, PaginationSupport.PAGESIZE, z ;>xI~
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startIndex); Ah5`Cnv
} fhGI
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public PaginationSupport findPageByCriteria tk'1o\@p9b
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(final DetachedCriteria detachedCriteria, finalint d??;r:
|]--sUx:
pageSize, lyY\P6
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finalint startIndex){ 87; E#2
return(PaginationSupport) :w|ef;
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getHibernateTemplate().execute(new HibernateCallback(){ `1}WQS
publicObject doInHibernate #m
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(Session session)throws HibernateException { ~s3X&!#
Criteria criteria = /V-uo(n< .
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detachedCriteria.getExecutableCriteria(session); 5`Q*
int totalCount = &B1j,$NRc
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((Integer) criteria.setProjection(Projections.rowCount RT+pB{Y
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()).uniqueResult()).intValue(); S2y_5XJ<D
criteria.setProjection ?3[Gh9g`
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(null); z):LF<
List items = 2VpKG*!\
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criteria.setFirstResult(startIndex).setMaxResults =Msr+P9Ai
Q$Q>pV;uH
(pageSize).list(); 58[=.rzD
PaginationSupport ps = o,r72>|
+56N}MAs
new PaginationSupport(items, totalCount, pageSize, DT;n)7+,
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startIndex); 6Qc
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return ps; \wjT|z1+Y
} hwx1 fpo4
}, true); _cc37[
} u0Q6+U
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public List findAllByCriteria(final fA$2jbGW
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DetachedCriteria detachedCriteria){ H*.v*ro9_
return(List) getHibernateTemplate G;ihm$Cad
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().execute(new HibernateCallback(){ HfOaJ'+e<
publicObject doInHibernate ;W 3#q:
(X?HuWTm
(Session session)throws HibernateException { dz6&TdEl
Criteria criteria = 1La?x'{2MP
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detachedCriteria.getExecutableCriteria(session); xe4`D>LUo
return criteria.list(); sB@9L L]&|
} <`V_H~Z
}, true); P7 h^!a/
} 9GX'+$R]
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public int getCountByCriteria(final \b;z$P\+*
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DetachedCriteria detachedCriteria){ og?L 9
Integer count = (Integer) <YM!K8hu$
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getHibernateTemplate().execute(new HibernateCallback(){ `t7z
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publicObject doInHibernate :@b=;
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(Session session)throws HibernateException { \zJb}NbnT
Criteria criteria = m0i,Zw{eM
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detachedCriteria.getExecutableCriteria(session); OwN~-).%-
return W5uC5C*,l
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criteria.setProjection(Projections.rowCount e +Ikw1y"f
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()).uniqueResult(); kr\#CW0?
} mwMc AUD]2
}, true); Z817f]l
return count.intValue(); k?}y@$[)
} z%;_h-
} mhMTn*9
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用户在web层构造查询条件detachedCriteria,和可选的 ?L| Ai\|
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 l>T]Y
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PaginationSupport的实例ps。 OYfRtfE
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ps.getItems()得到已分页好的结果集 u}?|d8$h\
ps.getIndexes()得到分页索引的数组 -nZDFC8y$
ps.getTotalCount()得到总结果数 `k7X|
ps.getStartIndex()当前分页索引 eF(oHn,
ps.getNextIndex()下一页索引 NE><(02qW
ps.getPreviousIndex()上一页索引 ` Nv1sA#C
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 N>iNz[a
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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 T3Sz<K$E
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一下代码重构了。 !ZM*)6^
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我把原本我的做法也提供出来供大家讨论吧: g77 :92
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首先,为了实现分页查询,我封装了一个Page类: or"9I1o
java代码: u
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/*Created on 2005-4-14*/ k_nQmU>
package org.flyware.util.page; 7e[&hea
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/** jw)c|%r>
* @author Joa `*xSn+wL`_
* <Wd_m?z
*/ &{bNa:@
publicclass Page { S
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TCK#bJ
/** imply if the page has previous page */ {]iM5?
privateboolean hasPrePage; zj$Ve
I/zI\PP,
/** imply if the page has next page */ #@F
privateboolean hasNextPage; RLO<5L
@o&UF-=MW(
/** the number of every page */ Ev T"+;9/p
privateint everyPage; ($!g= 7
;)vs=DK:)
/** the total page number */ 4O4}C#6(4
privateint totalPage; )"g @"LJ=
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/** the number of current page */ U^Iq]L
privateint currentPage; Y2|c;1~5$
sfp.> bMj
/** the begin index of the records by the current 9Qq%Fw_
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query */ ;,Os3
privateint beginIndex; "2:#bXM-
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/** The default constructor */ 8\bZ?n#dn
public Page(){ N.vkM`Z
A{wk$`vH
} >+%p}l:<\
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/** construct the page by everyPage sUZ2A1J}
* @param everyPage
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* */ PI)uBA;
public Page(int everyPage){ BPu>_$C
this.everyPage = everyPage; n>YgL}YZ?
} 9 LUk[V
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/** The whole constructor */ 7'7o^>
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public Page(boolean hasPrePage, boolean hasNextPage, 7U-?Rd
3V/f-l]X/
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int everyPage, int totalPage, T'7x,8&2|
int currentPage, int beginIndex){ hOe$h,E']
this.hasPrePage = hasPrePage; W|6.gN]
this.hasNextPage = hasNextPage; KA."[dVa
this.everyPage = everyPage; nz`"f,
this.totalPage = totalPage; |99Z&
<8f
this.currentPage = currentPage; u]<`y6=&C
this.beginIndex = beginIndex; X'5+)dj
} u2 U4MV1C
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/** P#2;1ki>
* @return X6oY-4O
* Returns the beginIndex. 9|hPl-.
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*/ :LB< z#M
publicint getBeginIndex(){ @_?8I_\:
return beginIndex; cKAZWON8;v
} j*jq2u
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/** <PQ[N[SU
* @param beginIndex \JGRd8S[
* The beginIndex to set. p+R8Mo;I
*/ <$`udP@
publicvoid setBeginIndex(int beginIndex){ pl.=u0 *
this.beginIndex = beginIndex; <~Tfi*^+
} 7@i2Mz/eV
MM Nz2DEy[
/** JmVha!<qk
* @return ;%PdSG=U
* Returns the currentPage. ]I0(_e|z}
*/ +isaqfy/
publicint getCurrentPage(){ ]TKM.[[
return currentPage; kN$L8U8f
} ,lw<dB@7"5
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/** /J'dG%
* @param currentPage A\<WnG>xjP
* The currentPage to set. *!+?%e{;b
*/ 0 }aw9g
publicvoid setCurrentPage(int currentPage){ +luW=j0V
this.currentPage = currentPage; "O{:jfq
} w5}2$r
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/** "zN]gz=OV>
* @return L QP4#7
* Returns the everyPage. [es-&X07<
*/ yO09NQ 5u
publicint getEveryPage(){ s)|l-I
return everyPage; O:G-I$F|
} {~:F1J~=
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/** 5>[j^g+@
* @param everyPage >a1ovKF
* The everyPage to set. AT,?dxP J
*/ h3:dO|Z
publicvoid setEveryPage(int everyPage){ |CjE}5Op>
this.everyPage = everyPage; W,)qE^+
} 5VPP 2;J
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/** as| MB
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* @return eEkbD"Q
* Returns the hasNextPage. RJZ4fl
*/ %O3 r>o=
publicboolean getHasNextPage(){ 79Vp^GG7
return hasNextPage; z|>f*Z
} KwuNHK)-
ni x1_Wo;
/** &tE#1<k
* @param hasNextPage OQh(qa
* The hasNextPage to set. Cdd
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*/ 5%6r,?/7KM
publicvoid setHasNextPage(boolean hasNextPage){ lGP'OY"Q
this.hasNextPage = hasNextPage;
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} ZX!u\O|w
s"\o6r
,
/** sGD b<
* @return &4O0}ax*Zm
* Returns the hasPrePage. FucLcq2Z
*/ 8TnByKZz
publicboolean getHasPrePage(){ MM%c
return hasPrePage; KI="O6 h
} <C_FI` wk
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/** 5:H9B
* @param hasPrePage UN}jpu<h
* The hasPrePage to set. <ctn_"p Z
*/ VJeN
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publicvoid setHasPrePage(boolean hasPrePage){ RT)*H>|
this.hasPrePage = hasPrePage; A@0%7xm
} ctL@&~*nY
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/** AhARBgf<
* @return Returns the totalPage. ivbuS-f=r
* -)tu$W*
*/ 0VB~4NNR
publicint getTotalPage(){ ~a5p_x P
return totalPage; aMFUJrXo
} r^k:$wJbRK
)[>b7K$f
/** DT@6Q.
* @param totalPage '%`Wy@
* The totalPage to set. Nd~?kZZu
*/ !ldb_*)h
publicvoid setTotalPage(int totalPage){ gHC -Y 0_
this.totalPage = totalPage; sgo({zA`i
} 5xi f0h-`
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} d"|XN{
O=#FpPHrdw
(@dh"=Lt\
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rs3Uk.Z^'
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 z$E+xZ
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个PageUtil,负责对Page对象进行构造: i=-zaboo
java代码: Wr7^
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/*Created on 2005-4-14*/ A}sb2P
package org.flyware.util.page; IBWUeB:b
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import org.apache.commons.logging.Log;
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import org.apache.commons.logging.LogFactory; Pn5@7~
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/** hq/\'Z&!+P
* @author Joa 'N],d&fu^^
* ?MuM _6
*/ :*e0Z2=
publicclass PageUtil { 0i9y-32-
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privatestaticfinal Log logger = LogFactory.getLog 0yXUVKq3
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(PageUtil.class); zGu(y@o
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/** [zK|OMxoV
* Use the origin page to create a new page hZ.Sj~>7`
* @param page %L{ H_;z
* @param totalRecords j_\sdH*r
* @return kqSCKY1
*/ {!xPq%
publicstatic Page createPage(Page page, int &~U8S^os
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totalRecords){ Tn/T:7C
return createPage(page.getEveryPage(), iqghcY)
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page.getCurrentPage(), totalRecords); y%=\E
} )__vPPko i
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/** +GgWd=X.Y
* the basic page utils not including exception BXaA#} ;e
,>2ijk#
handler EKk~~PhW 8
* @param everyPage {.z2n>1J{T
* @param currentPage FgNO# %
* @param totalRecords W{Ie(hf
* @return page jwTb09
*/ D*`|MzlQ
publicstatic Page createPage(int everyPage, int PX[taDN
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currentPage, int totalRecords){ 1okL]VrI
everyPage = getEveryPage(everyPage); &6PZX0M
currentPage = getCurrentPage(currentPage); N6$pOQ
int beginIndex = getBeginIndex(everyPage, Uq~{=hMX
|h*H;@$
currentPage); i=reJ(y-
int totalPage = getTotalPage(everyPage, ]~87v
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totalRecords); ME1lQ7E4B
boolean hasNextPage = hasNextPage(currentPage, iquB]z'
"a-Ex ]
totalPage); jio1#&
boolean hasPrePage = hasPrePage(currentPage); p(%7|'
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returnnew Page(hasPrePage, hasNextPage, 1a| q&L`o
everyPage, totalPage, 4<70mUnt
currentPage, 5P
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U{RW=sYB~9
beginIndex); IQoz8!guh:
} 85m[^WGyh
j.sxyW?3
privatestaticint getEveryPage(int everyPage){ $/5Jc[Ow
return everyPage == 0 ? 10 : everyPage; VCcLS3
} i15uHl
D.j'n-yw
privatestaticint getCurrentPage(int currentPage){ - P1OD)B
return currentPage == 0 ? 1 : currentPage; 8Cs)_bj#!
} oU$Niw9f
{IYfq)c
privatestaticint getBeginIndex(int everyPage, int z;GnQfYG
$=4T# W=m
currentPage){ &iR>:=ksN
return(currentPage - 1) * everyPage; 6/wAvPB$
} ^u:7U4
A0cC)bd&
privatestaticint getTotalPage(int everyPage, int X +*@
Va\dMv-b
totalRecords){ vO%n~l=
int totalPage = 0; n(/(F`
R(kr@hM
if(totalRecords % everyPage == 0) _,=A\C_b@
totalPage = totalRecords / everyPage;
@~U: |h
else Cv>|>Ob#
totalPage = totalRecords / everyPage + 1 ; )(9>r/bq
?&_ -,\t
return totalPage; &kHp}\
} J i :2P*
BP,"vq $'+
privatestaticboolean hasPrePage(int currentPage){ [95(%&k.Q
return currentPage == 1 ? false : true; gtyo~f
} MmI4J$F
Z2(z,pK
privatestaticboolean hasNextPage(int currentPage, +b.<bb6
(LA%q6
int totalPage){ JaXT
B"e
return currentPage == totalPage || totalPage == 75r>~@)*
iP~5=
0 ? false : true; LpGplDlB
} #gMMhB=
#Bg88!-4
&vLz{
} ,icgne1j
YxlV2hcX;
EQSOEf[
,@tkL!"9q
*$Z}v&-0k
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。 iN"kv
II3)Cz}xRG
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 $/Gvz)M
BDNn~aU#m
做法如下: P_B#
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 6B)(kPW
~.u}v~
F
的信息,和一个结果集List: 9
#TzW9
java代码: sNc(aGvy
B&Q\J>l9S
!lKO|Y
/*Created on 2005-6-13*/ %2f``48#
package com.adt.bo; R5g-b2Lm
*&q\)\(3w
import java.util.List; WM.JoQ
8V >j-C
import org.flyware.util.page.Page; .mn`/4
NKvBNf|D
/** WW{5[;LYiB
* @author Joa :.'<ndM
*/ &M,a+|yuY
publicclass Result { cTCo~Pk4
MIo<sJuv
private Page page; k*(c8/<.d
upg?
private List content; U":hJ*F)
l~;H~h!h/
/** t
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* The default constructor ((Ak/ qz
*/ ;&q}G1
public Result(){ I@+h|
n
super(); j2c -01}
} S_/9eI~X
<`i"5`J
/** >G$8\&]j
* The constructor using fields Bw;sg;
* -=iGl5P?
* @param page "~(qp_AI
* @param content F B9PIsFS
*/ /vll*}}
public Result(Page page, List content){ 1
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this.page = page; L6./b;
this.content = content; |iKk'Rta4
} (9%
ki$=}+
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/** %@#+Xpa+
* @return Returns the content. ^hzlR[
*/ U`N|pPe:w
publicList getContent(){ AD#]PSB
return content; V>ML-s9
} '9c`[^
GL[#XB>n
/** 4z#{nZG
* @return Returns the page. 3sIW4Cs7)U
*/ MGze
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public Page getPage(){ usH9dys,
return page; u?5d%]*
} R''nZ/R
S-}MS"
/** gD10C,{
* @param content <f.* =/]W2
* The content to set. gF-<%<RV
*/ Zu`;
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public void setContent(List content){ n8UQIa4&=
this.content = content; $R(?@B(
} to,DN2rN
("Z;)s4q
/** 4YDK`:4I~
* @param page ~XN--4%Q
* The page to set. ;*1bTdB5a
*/ uPKq<hBI
publicvoid setPage(Page page){ <_$]!Z6UR
this.page = page; ]E'BFon
} XI:8_F;Q
} \95qH,w)T
=F'p#N0_2
>}Qj|05G
Ec
IgX_\
PPk\W7G
2. 编写业务逻辑接口,并实现它(UserManager, <~;; iM6
JTK>[|c9oE
UserManagerImpl) *p:`F:
java代码: kP~'C'5Ys
%Xs3Lz
b~fX=!M
/*Created on 2005-7-15*/ ]x1MB|a6
package com.adt.service; bwo-9B
_a1 =?
import net.sf.hibernate.HibernateException; $2B_a
_J(n~"eR
import org.flyware.util.page.Page; xxkUu6x#
Fd Ezt
import com.adt.bo.Result; Atsi}zTR\
mkgGX|k;
/** 6hDK;J J&
* @author Joa 7?Q@Hj(:NT
*/ BC*vG=a
publicinterface UserManager { _nu,ks+
:MeshzWK
public Result listUser(Page page)throws D FDC'E
2gz}]_
HibernateException; kms&o=^
z@;]Hy
} ASmMj;>UM
<"A|Xv'Q
:*bv(~FW
8|^dM$
dv=y,q@W
java代码: %pj6[x`@
PN9^ sLx=
r@N 0%JZZ
/*Created on 2005-7-15*/ j
!^Tw.Ty
package com.adt.service.impl; {Hncm
:VwU2
import java.util.List; xg=}MoX
2VmQ%y6e"
import net.sf.hibernate.HibernateException; -
s[=$pDU
piYv}4;:(
import org.flyware.util.page.Page; OQzJRu)mF#
import org.flyware.util.page.PageUtil; F*V<L
<!b~7sZkTc
import com.adt.bo.Result; }$M 2XF
import com.adt.dao.UserDAO; ' =MaO@ @
import com.adt.exception.ObjectNotFoundException; fxfzi{}uj
import com.adt.service.UserManager; r@C2zF7
,XT#V\qne
/** nk.Y#+1)
* @author Joa [Du@go1C
*/ GT\,
@$r
publicclass UserManagerImpl implements UserManager { n\d`Fk
U'^AJ2L8
private UserDAO userDAO; +5J "G/f
'J^ M`/
/** bwh7.lDAl
* @param userDAO The userDAO to set. kN3 T/96
*/ mF!/8qk
publicvoid setUserDAO(UserDAO userDAO){ [ZwZGAP
this.userDAO = userDAO; yMdEH-?/
} `$og]Dn;
d:/8P985
/* (non-Javadoc) W: Rs 0O
* @see com.adt.service.UserManager#listUser @L^Fz$Sx
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(org.flyware.util.page.Page) <viIpz2jh%
*/ A
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public Result listUser(Page page)throws _&S?uz m
;>^oe:@
HibernateException, ObjectNotFoundException { iku8T*&uc
int totalRecords = userDAO.getUserCount(); 0kN;SSX!
if(totalRecords == 0) JA W}]:jC
throw new ObjectNotFoundException tX;00g;U.
4d&#NP
("userNotExist"); o(xRq;i
page = PageUtil.createPage(page, totalRecords); #_yQv? J
List users = userDAO.getUserByPage(page); rfqw/o
returnnew Result(page, users); Gvo(iOU
} @$FE}j_
|1^>n,C
} _^4\z*x
>Gbj1>C}
n^|;J*rD
lB!`,>"c
eUQ., mP
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 !:e|M|T'I*
<>aBmJs4
询,接下来编写UserDAO的代码: 5 e:Urv77
3. UserDAO 和 UserDAOImpl: )6|7L)Dk
java代码: `(A6uakd
=PHl|^
gLv|Hu7
/*Created on 2005-7-15*/ `abQlBb*
package com.adt.dao; j]7|5mC78
c>fLSf
import java.util.List; F-}-/N]o
q
\8\)5#?
import org.flyware.util.page.Page; l@`D;m
MWf ]U
import net.sf.hibernate.HibernateException; l,uYp"F,ps
eeIh }t>[
/** +3.Ik,Z}zq
* @author Joa x_1JQDE
*/ }*Qd]\fy
publicinterface UserDAO extends BaseDAO { tq=1C=h
.(o]d{ '-}
publicList getUserByName(String name)throws T!$7:% D
zb9^ii$g
HibernateException; jB }O6u[%
&d`T~fl|
publicint getUserCount()throws HibernateException; )/k0*:OMyO
0z?b5D;
publicList getUserByPage(Page page)throws ^}; 4r
Lm+!/e
HibernateException; BqZ^ I eC$
#QJ
mAA
} N/)mw/?i
Z&8
7Aj
GF~^-5
*nNzhcuR
-oq!zi4:
java代码: 4mOw[}@A
t
K;E&:
7SzY0})<U
/*Created on 2005-7-15*/ K#M
h
package com.adt.dao.impl; g!n1]- 1
,oe
e'
import java.util.List; -Hzn7L
^|}C!t+
import org.flyware.util.page.Page; 2{s ND
J<DV7zV
import net.sf.hibernate.HibernateException; b~06-dk1
import net.sf.hibernate.Query; ulFU(%&
iHjo3_g)n
import com.adt.dao.UserDAO; eux_tyC
O%v(~&OSl
/** }yqRz6=YB
* @author Joa J#*Uf>5NY
*/ lEi,duS)
public class UserDAOImpl extends BaseDAOHibernateImpl oTtmn,
T
mOwgk7s[J
implements UserDAO { >7!aZO
_dqjRhu
/* (non-Javadoc) &QE^i%6>\
* @see com.adt.dao.UserDAO#getUserByName #1Mk9sxo
EZ #UdK_
(java.lang.String) *lv)9L+0
*/ @RotJl/>
publicList getUserByName(String name)throws O;[PEV~
BEvSX|M>x
HibernateException { n? "ti
String querySentence = "FROM user in class )ufHk
%Hv$PsSJ
com.adt.po.User WHERE user.name=:name"; aM 0kV.O
Query query = getSession().createQuery x6HebIR+
nzy =0Ox[
(querySentence); LoHWkNZ5:
query.setParameter("name", name); QxnP+U~N
return query.list(); 3DK^S2\zBm
} o!mfd}nG
d;S:<]l'
/* (non-Javadoc) ->wY|7
* @see com.adt.dao.UserDAO#getUserCount() ;]fpdu{
*/ hgj#VY$B
publicint getUserCount()throws HibernateException { F$r8hj`
int count = 0; 567ot|cc
String querySentence = "SELECT count(*) FROM 5!#"8|oY
el!Bi>b9c!
user in class com.adt.po.User"; w|WZEu:0|
Query query = getSession().createQuery A`(p6 H"s
V$
38
(querySentence); *wt yyP@
count = ((Integer)query.iterate().next qh$D;t1=
{#QFDA
()).intValue(); |}Mkn4
return count; sxL;o>{
} ]wne2 WXE
mXc/sh")X
/* (non-Javadoc) &o"Hb=k<
* @see com.adt.dao.UserDAO#getUserByPage }=A6Jv(j
T.ub!,Y
(org.flyware.util.page.Page) :&yRvu
*/ !Go(8`>
publicList getUserByPage(Page page)throws |L;'In
:EgdV
HibernateException { CW\o>yh
String querySentence = "FROM user in class /p\Ymq
yD1*^~ loJ
com.adt.po.User"; 2DQ'h}BI
Query query = getSession().createQuery yE9JMi0
6(9Ta'ywZ
(querySentence); 1@)]+* F*z
query.setFirstResult(page.getBeginIndex()) gbpm::
.setMaxResults(page.getEveryPage()); k6JB%m\E
return query.list(); 8e\a_R*(|
} i`&