Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 `LVX|l62
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 O7T wM Yh
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 N/mC,7Q
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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 ,0[h`FN
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分页支持类: 81U(*6
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java代码: ,LJX
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package com.javaeye.common.util; cwA+?:Ry}
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import java.util.List; D'+kzb@
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publicclass PaginationSupport { kculHIa\.
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publicfinalstaticint PAGESIZE = 30; |7l*
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privateint pageSize = PAGESIZE; W%RjjLJ@
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privateList items; 9l:Bum)9
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privateint totalCount; G@igxnm}
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privateint[] indexes = newint[0]; !B{N:?r
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privateint startIndex = 0; #~^Y2-C#
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public PaginationSupport(List items, int C/Dc1sj
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totalCount){ S_B;m1
setPageSize(PAGESIZE); r z%=qY
setTotalCount(totalCount); Yj^n4G(h
setItems(items); rTjV/~
setStartIndex(0);
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} C0F#PXUy
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public PaginationSupport(List items, int k;pTOj
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totalCount, int startIndex){ ye)CfP=ID\
setPageSize(PAGESIZE); G6(U\VFqO
setTotalCount(totalCount); Ue<Y ~A
setItems(items); QNH5Cq;Y
setStartIndex(startIndex); w%[`'_[
} qwU,D6
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public PaginationSupport(List items, int ggUJ -M'2h
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totalCount, int pageSize, int startIndex){ L
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setPageSize(pageSize); @iwg`j6ol
setTotalCount(totalCount); 6
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setItems(items); Svo gvn
setStartIndex(startIndex); 'i|z>si[*
} X,<n|zp
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publicList getItems(){ `}^_>
return items; *@r)3
} T&=1IoOg
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publicvoid setItems(List items){ KN;b+`x;M
this.items = items; $b/oiy!=|3
} "1H?1"w~
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publicint getPageSize(){ u"\HBbBx
return pageSize; Y.qlY3iBp
} Cu0N/hBT
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publicvoid setPageSize(int pageSize){ ttPa[h{!
this.pageSize = pageSize; ruLi
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} AoEG%nT
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publicint getTotalCount(){ YN
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return totalCount; I"^ `!8<q
} qsUlfv9L6
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publicvoid setTotalCount(int totalCount){ &LO<!WKQ
if(totalCount > 0){ HPGi5rU
this.totalCount = totalCount; f_r1(o5:Y
int count = totalCount / 3n/U4fn_
aUN!Sd2,
pageSize; hmOhXE[a&
if(totalCount % pageSize > 0) ?3"bu$@8
count++; wY2#xD
indexes = newint[count]; xoD5z<<
for(int i = 0; i < count; i++){ 3r?Bnf:
indexes = pageSize * Z_Ox '
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i; zF'{{7o
} /s>ZT8vaAs
}else{ iXc-_V6
this.totalCount = 0; DT_HG|
} %Lexu)odW
} >WMH.5p
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publicint[] getIndexes(){ 4Wq{ch
return indexes; Cyxt EzPp
} 1o7
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publicvoid setIndexes(int[] indexes){ 6|m1z
this.indexes = indexes; }*m:zD@8$
} _^'fp
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publicint getStartIndex(){ ysfR@ sH7
return startIndex; )p>BN|L
} Cd.pMoS
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publicvoid setStartIndex(int startIndex){ `Y-uNJ'.N
if(totalCount <= 0) P. P3/,
this.startIndex = 0; IBY3QG
elseif(startIndex >= totalCount) DNdwMSwp
this.startIndex = indexes 0s:MEX6w|
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[indexes.length - 1]; W$@q
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elseif(startIndex < 0) 1sZwW P
this.startIndex = 0; 6I(y`pJ
else{ W{l+_a{/9
this.startIndex = indexes 2f>lgZ!
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[startIndex / pageSize]; *plsZ*Q8
} uAR!JJ
} $!Z6?+
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publicint getNextIndex(){ B2%)G$B
int nextIndex = getStartIndex() + SC`.VCfc.
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pageSize; )'xTDi
if(nextIndex >= totalCount) AZxx%6
return getStartIndex(); Gd`qZqx#
else WEUr;f
return nextIndex; n8Jx;j
} ?@l9T)fF
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publicint getPreviousIndex(){ X%xX3e'
int previousIndex = getStartIndex() - ;g: TsYwM
{IJV(%E
pageSize; Y4}!9x
if(previousIndex < 0) `h(JD$w
return0; ZPn`.Qc
else 9j:t}HV
return previousIndex; *I`, L/
} db:b%1hk:
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} Q <EFd
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抽象业务类 too=+'<N</
java代码: iCao;Zb
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/** !zwnFdp
* Created on 2005-7-12 p-UACMN&c
*/ I)V2cOrXM
package com.javaeye.common.business; p8Di9\}
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import java.io.Serializable; \y{Bnp5h
import java.util.List; @P6K`'.0
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import org.hibernate.Criteria; FD*`$.e3\
import org.hibernate.HibernateException; ?C//UN;
import org.hibernate.Session; MftW^7W-
import org.hibernate.criterion.DetachedCriteria; :S0r)CNP
import org.hibernate.criterion.Projections; 97e fWYj
import aG8}R~wH&
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org.springframework.orm.hibernate3.HibernateCallback; iDlIx8PI
import bqN({p&
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org.springframework.orm.hibernate3.support.HibernateDaoS 3zp)!QJi
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upport; (EIdw\
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import com.javaeye.common.util.PaginationSupport; .B{3=z^
)?joF)
public abstract class AbstractManager extends <w(UDZ
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HibernateDaoSupport { ^.&uYF&
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privateboolean cacheQueries = false; ,Ww)>O+
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privateString queryCacheRegion; Z$kff-Y4
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publicvoid setCacheQueries(boolean 1bF aQ50t
Pon 2!$
cacheQueries){ W`^'hka
this.cacheQueries = cacheQueries; pvQw+jX
} q-eC=!#}
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publicvoid setQueryCacheRegion(String (]^9>3{|
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queryCacheRegion){ \/la`D
this.queryCacheRegion = cP`f\\c
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queryCacheRegion; n'v[[bmu
} oh-Y
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publicvoid save(finalObject entity){ Bjq1za
getHibernateTemplate().save(entity); ZOK2BCoW
} v#@"Evh7
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publicvoid persist(finalObject entity){ b/5?)!I
getHibernateTemplate().save(entity);
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} ]C3{ _?=
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publicvoid update(finalObject entity){ 2HoTj|
getHibernateTemplate().update(entity); m{x[q
} S=~[ 6;G
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publicvoid delete(finalObject entity){ fAm^-uq[
getHibernateTemplate().delete(entity); ^](sCE7
} d+rrb>-OU
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publicObject load(finalClass entity, /qed_w.p
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finalSerializable id){ _d76jmujJ
return getHibernateTemplate().load A&jkc '
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(entity, id); X#'DS&{
} 'Xoif"
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publicObject get(finalClass entity, P {i\x#
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finalSerializable id){ >N62t9Ll[
return getHibernateTemplate().get 5,})x]'x
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(entity, id); 0f&B;?)!
} So{/V%
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publicList findAll(finalClass entity){ +%7v#CY
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return getHibernateTemplate().find("from H=9kDP${
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" + entity.getName()); F&%@p&
} Gole7I
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publicList findByNamedQuery(finalString 0_q8t!<xJw
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namedQuery){ <k!M+}a 9V
return getHibernateTemplate njtz,qt_;G
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().findByNamedQuery(namedQuery); GPz0qK
} NY
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publicList findByNamedQuery(finalString query, 1)pwR3(^Fz
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finalObject parameter){ 3O7]~5 j1
return getHibernateTemplate 0uV3J
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().findByNamedQuery(query, parameter); \@;$xdA$
} (-Cxv`7
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publicList findByNamedQuery(finalString query, ^MIF+/bQ
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finalObject[] parameters){ <*EMcZ
return getHibernateTemplate qmqWMLfC
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().findByNamedQuery(query, parameters); G2qv)7{l2
} J9eOBom8e<
i)y8MlC{
publicList find(finalString query){ G%^jgr)
return getHibernateTemplate().find 94VtGg=b}
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(query); LvtHWt
} 5{Q5?M]
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publicList find(finalString query, finalObject :B{Wf 2<z
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parameter){ OL]P(HRm]~
return getHibernateTemplate().find T<yAfnTb`
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(query, parameter); r5 tn'
} >*s_)IH2
}py)EI,U
public PaginationSupport findPageByCriteria [As9&]Bv5
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(final DetachedCriteria detachedCriteria){ oC
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return findPageByCriteria yN[aBYJx,M
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); "Vh3hnS~
} \]C_ul'
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public PaginationSupport findPageByCriteria J,4,#2M8
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(final DetachedCriteria detachedCriteria, finalint ` _aX>fw
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startIndex){ !LI6_Oq
return findPageByCriteria Z$?(~ln
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(detachedCriteria, PaginationSupport.PAGESIZE, /tm2b<G
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startIndex); P5Lb)9_Jw
} @k=UB&?I
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public PaginationSupport findPageByCriteria 88Nx/:#Y*
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(final DetachedCriteria detachedCriteria, finalint RW~!)^
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pageSize, Z8C~o)n9
finalint startIndex){ e"oTlB
return(PaginationSupport) Ri>4:V3K
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getHibernateTemplate().execute(new HibernateCallback(){ U#V&=~-
publicObject doInHibernate R2Es~T
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(Session session)throws HibernateException { rn^cajO^
Criteria criteria = I(<9e"1O
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detachedCriteria.getExecutableCriteria(session); y1{TVpN
int totalCount = n6AA%? 5
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((Integer) criteria.setProjection(Projections.rowCount r7)qr%n
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()).uniqueResult()).intValue(); }7non
criteria.setProjection H;nEU@>"Z
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(null); c@3mfc{
List items = !"2S'oQKS
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criteria.setFirstResult(startIndex).setMaxResults Ff{,zfN+3
u6nO\.TTtY
(pageSize).list(); 3Fb9\2<H
PaginationSupport ps = (>
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new PaginationSupport(items, totalCount, pageSize, {,i-V57-h
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startIndex); IU<lF) PF$
return ps; r;xy/*%Mtj
} DuNindo8
}, true); KF6C=,Yc%
} %ufh
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public List findAllByCriteria(final re_nb)4g
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DetachedCriteria detachedCriteria){ Pz34a@%"
return(List) getHibernateTemplate LPBa!fq
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().execute(new HibernateCallback(){ 51JB,}dGH}
publicObject doInHibernate $[}EV(#y
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(Session session)throws HibernateException { iGSA$U P|
Criteria criteria = ?m5EXe
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detachedCriteria.getExecutableCriteria(session); 1
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return criteria.list(); MT"&|Og
} 'da
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}, true); ' Ut4=@)
} ;@T0wd_i|
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public int getCountByCriteria(final q8&l%-d`
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DetachedCriteria detachedCriteria){ H0#=oJr$)W
Integer count = (Integer) $'I&u
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getHibernateTemplate().execute(new HibernateCallback(){ 04jvrde8-O
publicObject doInHibernate I ^m
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(Session session)throws HibernateException { J,:&U
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Criteria criteria = l_/(J)|a
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detachedCriteria.getExecutableCriteria(session); zPND$3&'
return M,S'4Szuk
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criteria.setProjection(Projections.rowCount %0} ^M1
}dop]{RG
()).uniqueResult(); _crhBp5@T3
} w8>h6x"
}, true); GLyPgZ`|
return count.intValue(); vjS=ZinN"
} /ZD 6pF
} m)} 01N4
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用户在web层构造查询条件detachedCriteria,和可选的 \?>M?6D
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 MNWI%*0LO
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PaginationSupport的实例ps。 fCx(
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ps.getItems()得到已分页好的结果集 l>}f{az-T
ps.getIndexes()得到分页索引的数组 dgF%&*Il]O
ps.getTotalCount()得到总结果数 o^vX\a?`u
ps.getStartIndex()当前分页索引 fE+zA)KX
ps.getNextIndex()下一页索引 '"fJA/O
ps.getPreviousIndex()上一页索引 Hl0"
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 3y6\0|{1
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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 H#_Zv]
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一下代码重构了。 /@k#tdj
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我把原本我的做法也提供出来供大家讨论吧: 0o=HOCL\
bsF_.S*k@
首先,为了实现分页查询,我封装了一个Page类: :R,M Y"(
java代码: >Ua'*
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/*Created on 2005-4-14*/ +Cw_qS"=
package org.flyware.util.page; \4q|Qno8
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/** :.,9}\LK
* @author Joa 3NtUB;!
* b$7]cE
*/ 3$nK
publicclass Page { JP5e=Z<
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/** imply if the page has previous page */ h6
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privateboolean hasPrePage; kun/KY
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/** imply if the page has next page */ }yEV&&
@
privateboolean hasNextPage; A/>Q5)
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/** the number of every page */ e~SK*vR%]
privateint everyPage; ?`piie9V
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/** the total page number */ ^
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privateint totalPage; 985F(r
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/** the number of current page */ qh~bX
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privateint currentPage; I "AjYv4R
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/** the begin index of the records by the current dT|f<E/P
tp] 5[U
query */ Q v9q~l
privateint beginIndex; f1MRmp-f'
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/** The default constructor */ NS[eQ_rT
public Page(){ '`P%;/z
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} t]LiFpy2IC
= {O ~
/** construct the page by everyPage 7y'":1
* @param everyPage fY!?rZ)$
* */ Sf*)Z3f
public Page(int everyPage){ 35& ^spb
this.everyPage = everyPage; N `|A
} \)6glAtN
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/** The whole constructor */ *p}mn#ru-
public Page(boolean hasPrePage, boolean hasNextPage, Y<xqws
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int everyPage, int totalPage, Jj-\Eb?
int currentPage, int beginIndex){ _RbfyyaN
this.hasPrePage = hasPrePage; JN0h3nZ_
this.hasNextPage = hasNextPage; Cs6`lX >
this.everyPage = everyPage; ;5 j|B|v
this.totalPage = totalPage; $jN.yNm0
this.currentPage = currentPage; ?G,4N<]Nu
this.beginIndex = beginIndex; V)^Xz8H_
} UX)GA[WI
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/** JI"/,fK^
* @return qVn<c,8#
* Returns the beginIndex. 5*YoK)2J
*/ ~Ru\Z-q1
publicint getBeginIndex(){ G(&[1V % x
return beginIndex; ^PZ[;F40
} -+*h'zZ[<w
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/** Y !<m8\
* @param beginIndex hQn?qJy%W
* The beginIndex to set.
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*/ cE]z Tu?!
publicvoid setBeginIndex(int beginIndex){ <7^|@L
6
this.beginIndex = beginIndex; v~nKO?{
} BsQ;`2
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/** *
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* @return UM7@c7B?
* Returns the currentPage. iq; |
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*/ YN8x|DLi?
publicint getCurrentPage(){ U]3!"+Y1P
return currentPage; L`+[mX&2B
} op6]"ZV-C
g*V.u]U!i
/** yfG;OnkZ
* @param currentPage LZykc
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* The currentPage to set. ")Fd'&58
*/ Rt8[P6e"q
publicvoid setCurrentPage(int currentPage){ ]Z!Y*v
this.currentPage = currentPage; `nPdZ.
} UQl?_[G
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/** .WF"vUp
* @return C]ss'
* Returns the everyPage. $plk>Khg
*/ fs!dI
publicint getEveryPage(){ 8}'iEj^e
return everyPage; @;/Pl>$|'G
} r[L.TX3Ah=
46C%at
M0}
/** 4Q|>k)H
* @param everyPage Cj0r2^`
* The everyPage to set. hG1$YE
*/ *rq*li;
publicvoid setEveryPage(int everyPage){ |bnd92fvks
this.everyPage = everyPage; G+
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} 0+>g/>
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/** =3bk=vy
* @return <XeDJ8
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* Returns the hasNextPage. m%|\AZBA#
*/ '.Y,VJaL
publicboolean getHasNextPage(){ 7<j!qWm0
return hasNextPage; tia}&9;
} Ik:G5m<ta
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/** ,
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* @param hasNextPage cC*WZ]
* The hasNextPage to set. DsdM:u*s
*/ UFB|IeX?q
publicvoid setHasNextPage(boolean hasNextPage){ iJTG+gx
this.hasNextPage = hasNextPage; b<u\THy#
} n_QuuUB
/$; Z ~^P
/** , cxqr3
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* @return 4&*lpl*N
* Returns the hasPrePage. =D(a~8&,
*/ :|j[{;asY
publicboolean getHasPrePage(){ 7ZUN;mr
return hasPrePage; ().C
} t#(NfzN
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/** #aqnj+
* @param hasPrePage h[(YH ;Y
* The hasPrePage to set. IjhRSrCv
*/ Q
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publicvoid setHasPrePage(boolean hasPrePage){ G"r{!IFL
this.hasPrePage = hasPrePage; =9&2udV1
} (u?s@/e:`/
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/** kH 9k<{
* @return Returns the totalPage. M>k&WtqK
* Zl5DlRuw
*/ dOD(<
publicint getTotalPage(){ Md6u4c
return totalPage; B}
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} r,eH7&P9{
t_/qd9Jv
/** rbf5~sw&8+
* @param totalPage ZPf&4#|
* The totalPage to set. n l5+#e*\
*/ thPAD+u.3
publicvoid setTotalPage(int totalPage){ x.gz sd
this.totalPage = totalPage; q`AsnAzo&
} pll5m7[
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} fTmJDUv+
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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 ?~ybFrc
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个PageUtil,负责对Page对象进行构造: uJ"#j
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java代码: ,,FhE
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# wn>S<
/*Created on 2005-4-14*/ E2hML
package org.flyware.util.page; j\#)'>"
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import org.apache.commons.logging.Log; pDC`Fi
import org.apache.commons.logging.LogFactory; dnANlNMk?
Z){fie4WM
/** |$8N*7UD
* @author Joa NrcV%-+u%
* ^g'uR@uU
*/ TGpdl`k\T
publicclass PageUtil { af'ncZ@U
*<9M|H~
privatestaticfinal Log logger = LogFactory.getLog BAqwYWdS
e{:
-N
(PageUtil.class); x}C$/ 7^
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/** 98}l`J=i
* Use the origin page to create a new page 8yr-X!eF
* @param page &Ai+t2
* @param totalRecords ziAn9/sT
* @return 0s4]eEXH
*/ 'mU\X!-
4<
publicstatic Page createPage(Page page, int nQw, /Lk
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totalRecords){ @M*5q# s
return createPage(page.getEveryPage(), Ob'[W;p)[w
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page.getCurrentPage(), totalRecords); Kt#X'!9/<
} s4 Uk5<
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/** t-FrF </0
* the basic page utils not including exception )q7!CG'oY
mqQ//$Y
handler r^d:Po
* @param everyPage Kn+B):OY+
* @param currentPage M4XU*piz
* @param totalRecords Mc|UD*Z
* @return page S?H
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*/ }e1]Ib!
publicstatic Page createPage(int everyPage, int cTJG1'm
`?"[u"*
currentPage, int totalRecords){ uoY]@.
everyPage = getEveryPage(everyPage); ECOzquvM
currentPage = getCurrentPage(currentPage); ~RM_c
int beginIndex = getBeginIndex(everyPage, uQkFFWS
^@maF<Jb
currentPage); p6{8t}
int totalPage = getTotalPage(everyPage, 0bIhP,4&
9H%L;C5<
totalRecords); d_Y7/_i
boolean hasNextPage = hasNextPage(currentPage, }!vJ+
"CQ:<$|$
totalPage); [{-;cpM\
boolean hasPrePage = hasPrePage(currentPage); DTV"~>@
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returnnew Page(hasPrePage, hasNextPage, Gy[m4n~Z5
everyPage, totalPage, ]\%u9,b%!
currentPage, "IdN *K
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beginIndex); )e\IdKl=
} n ^C"v6X
SnW>`
privatestaticint getEveryPage(int everyPage){ z!\)sL/"
return everyPage == 0 ? 10 : everyPage; "\Nn,3qp
} ,
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]OA8H[U-eA
privatestaticint getCurrentPage(int currentPage){ (^Hpe5h&
return currentPage == 0 ? 1 : currentPage; r7:4|6E
} [lAZ)6E~=
dxeLu
privatestaticint getBeginIndex(int everyPage, int }W* q
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d"8
currentPage){ z)y{(gR
return(currentPage - 1) * everyPage; [Gb8o'
} [[0u|`T/
lxD~[e
privatestaticint getTotalPage(int everyPage, int w'D=K_h
Zut"P3d=J
totalRecords){ +dSO?Y]
int totalPage = 0; \ssqIRk
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if(totalRecords % everyPage == 0) DlbNW& V
totalPage = totalRecords / everyPage; }EWPLJA
else -]~vEfq+T
totalPage = totalRecords / everyPage + 1 ; 5XA{<)$
<@2g.+9
return totalPage; CrI:TB>/"
} %FO#j 6
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privatestaticboolean hasPrePage(int currentPage){ .qk_m-o
return currentPage == 1 ? false : true; N(^
q%eHp
} a{7'qmN1
":N
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privatestaticboolean hasNextPage(int currentPage, q'[q]
\B~}s }
int totalPage){ OB5`a,5dI
return currentPage == totalPage || totalPage == BO)Q$*G~JD
Z |CL:)h
0 ? false : true; .+ g8zbD4
} +>S\.h
s4
wLz@u$u?
j]'7"b5
} h#rziZ(
E#m|Sq
;/g Bjp]H
aoVfvz2Y
/V@9!
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。 R<n'v.~"A
;4ETqi9
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 z<9wh2*M
'9d]
B^)F
做法如下: i@p0Jnh|
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 hMvLx>q3)
^9*kZV<K
的信息,和一个结果集List: V1Opp8
java代码: ~*Kk+w9H<
P4S]bPIp
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/*Created on 2005-6-13*/ of k@.TmO
package com.adt.bo; Ga1(T$|H
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import java.util.List; Doj>Irj?7
5ps7)]
import org.flyware.util.page.Page; n6]8W^g
Y(3X5v?[
/** a08`h.dyN
* @author Joa &@h(6
*/ ~dc~<hK
publicclass Result { DYFfq
<@z!kl
private Page page; cg]>*lH
&nyJ :?
private List content; 9#X"m,SB
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/** 5b5Hc Inu
* The default constructor Ri mz~}+
*/ +<o}@hefY2
public Result(){ hiQ #<
super(); qzt.k^'-^
} T>2_ r6;
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/** waI:w,
* The constructor using fields ]n9gnE
* LW '3m5
* @param page nqMXE82
* @param content z[~ph/^
*/ >j$y@"+
public Result(Page page, List content){ ;bhD:$NB X
this.page = page; s7>a
this.content = content; ?6T\uzL +%
} g#/"3P2H
kt;uB
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/** V>Vu)7
* @return Returns the content. 6A23H7
*/ 'NYW`,
publicList getContent(){ }s++^uX6
return content; 9 m`VIB
} Z]\VOA>
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/** Q^!x8oUF
* @return Returns the page. l}MVk%[
*/ 8%EauwAx
public Page getPage(){ #<*=) [
return page; 'YTSakNJ}
} &b:SDl6
D@
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/** B9h'}460H
* @param content qb1JE[2F
* The content to set. tEFbL~n
*/ !/RL.`!>
public void setContent(List content){ QopA'm
this.content = content; !}pvrBS
} +Cg[!6[#
.:/[%q{k
/** %-J}m
* @param page P4{!/&/
* The page to set. *P0sl( &
*/ E,p4R%:$@1
publicvoid setPage(Page page){ dp DPSI
this.page = page; 3 =-XA2zJ
} Q8
} RHv|ijYy
V3v/hV:
8qF OO3c\V
-4!S?rHwd+
GMW,+
2. 编写业务逻辑接口,并实现它(UserManager, 3EO:Uk5<
ki=]#]rg
UserManagerImpl) _A]=45cn~
java代码: T6M=BkcP
i8|0zI
%s*F~E
/*Created on 2005-7-15*/ m4~>n(
package com.adt.service; K$kI%eGZA
+b_o2''
import net.sf.hibernate.HibernateException; ~U$ioQy<
O~DdMW
import org.flyware.util.page.Page; E@[ZwTnJ
X-k$6}D
import com.adt.bo.Result; bBg=X}9
=+ALh-
/** _?rL7oTv
* @author Joa 94Q?)0W$
*/ U#>K(
publicinterface UserManager { ;%B:1Z
VbfTdRD-
public Result listUser(Page page)throws /w
"h'u
ly( LMr
HibernateException; "rU
2g
HVH <S
} iOXsj
+
C'<*
`RHhc{
uRCZGg&V?#
B:rzM:BQ
java代码: `/RcE.5n\@
Gc*p%2c
6BH
P#B2j
/*Created on 2005-7-15*/ CKy/gTN
package com.adt.service.impl; P TMJ.;
wrm
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import java.util.List;
x=YV*
Vqp3'=No
import net.sf.hibernate.HibernateException; 0'zX6%
mTgsvC
import org.flyware.util.page.Page; [Ufx=BPx3
import org.flyware.util.page.PageUtil; GD@|XwK){
MHPh!
import com.adt.bo.Result; '
o(7@
import com.adt.dao.UserDAO; [DD#YL\P
import com.adt.exception.ObjectNotFoundException; 'y%*W:O
import com.adt.service.UserManager; aW*8t'm;m'
t~_bquGk
/** :R1F\FT*
* @author Joa I4(z'C
*/ [
~:wS@%
publicclass UserManagerImpl implements UserManager { ;i-<dAV8B
V(wANvH
private UserDAO userDAO; Ex-?[Hq
iCIU'yI
/** Ye]-RN/W
* @param userDAO The userDAO to set. BFvRU5&Sz
*/ $A^OP{
publicvoid setUserDAO(UserDAO userDAO){ ?.Lq`~T`
this.userDAO = userDAO; <`")Zxf+
} ]=vRjw
)QAS 7w#k
/* (non-Javadoc) FwwOp"[~t
* @see com.adt.service.UserManager#listUser ICD;a
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(org.flyware.util.page.Page) Dks"(0g
*/ ;5&=I|xqe
public Result listUser(Page page)throws WPDi)UX
2g
HRfTF
HibernateException, ObjectNotFoundException { YckLz01jh
int totalRecords = userDAO.getUserCount(); f^|r*@o
if(totalRecords == 0) pSdtAv
throw new ObjectNotFoundException jL,P )TC
-)9aY.
("userNotExist"); w=kW~gg
page = PageUtil.createPage(page, totalRecords); Lk2;\ D>
List users = userDAO.getUserByPage(page); W*~[KdgC
returnnew Result(page, users); ukc<yc].+?
} IN?6~O
p
*('Vyd!n
} f,'^"Me$c
J;GYo|8
qZYh^\
e'T|5I0K
D9%t67s
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 7bY N
N?v}\ PU
询,接下来编写UserDAO的代码: g_;4@jwTP"
3. UserDAO 和 UserDAOImpl: 1T0s
UIY
java代码: q);@iiJ-
zbAyYMtEk
e/R$Sfj]
/*Created on 2005-7-15*/ @cB6,iUr
package com.adt.dao; )-^[;:B\k"
#n.XOet<\
import java.util.List; ,'%*z
->)0jZax
import org.flyware.util.page.Page; ~n;U5hcB
j7yUya&
import net.sf.hibernate.HibernateException; KJi8LM
NeR1}W
/** n8Rsle`a
* @author Joa =y0h\<[
*/ F4$9r^21r
publicinterface UserDAO extends BaseDAO { A7R [~
?X@uR5?{
publicList getUserByName(String name)throws Np@RK1}
=3|5=ZU034
HibernateException; .TO#\!KBv
yX%NFXD
publicint getUserCount()throws HibernateException; 7Cx-yv
e4<St`K
publicList getUserByPage(Page page)throws hVW1l&s
OZ4% 6/
HibernateException; jqQG n"!
q.ZkQN+
} U*\1d
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F7\nG}#s
r#B{j$Rw
9a]J Q
java代码: 6ag0c&k
I]Ws
'o|=_0-7W
/*Created on 2005-7-15*/ OjsMT]
package com.adt.dao.impl; FL[w\&fp
"c*#ZP
import java.util.List; <~
?LU^
x.>&|Ej
import org.flyware.util.page.Page; Q*8efzgs|
ZM_-g4[H
import net.sf.hibernate.HibernateException; $|VD+[jSV
import net.sf.hibernate.Query; UcWf
O!}D
VEx
)
import com.adt.dao.UserDAO; (r/))I9^
x,Z:12H0
/** Erm]uI9`
* @author Joa zKFiCP
K
*/ q OV$4[r
public class UserDAOImpl extends BaseDAOHibernateImpl /2Bf6
q3ebps9^
implements UserDAO { @5{h+ ^
D
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/* (non-Javadoc) }[: i!t.m
* @see com.adt.dao.UserDAO#getUserByName 3XhLn/@
Z9zsvg
(java.lang.String) =xr2-K)e
*/ /;WFRp.
publicList getUserByName(String name)throws KSO%89R'
Kza5_7p`L
HibernateException { y<m}dW6[\
String querySentence = "FROM user in class e?<$H\
b$Q#Fv&P
com.adt.po.User WHERE user.name=:name"; B6U4>ZN
Query query = getSession().createQuery },,K6*P
f<vZ4 IU
(querySentence); /gP"X1.
query.setParameter("name", name); 1 }_"2
return query.list(); Lv@'v4.({
} -932[+
?|{tWR,Vb
/* (non-Javadoc) &?^"m\K4J*
* @see com.adt.dao.UserDAO#getUserCount() Thuwme
*/ 9j<