Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 /-p!|T}w
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 &1Ndi<Y^
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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 esJ7#Gxt
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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 j4owo#OB-
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分页支持类: e>z"{ u(F0
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java代码: %(6IaqJ[
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package com.javaeye.common.util; p{L;)WTI
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import java.util.List; 2Xl+}M.:Y
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publicclass PaginationSupport { -US:a8`
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publicfinalstaticint PAGESIZE = 30; FY'0?CT$
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privateint pageSize = PAGESIZE; s-IE}I?;
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privateList items; QH-CZ6M
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privateint totalCount; Rv&"h_"t
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privateint[] indexes = newint[0]; G^Gs/-
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privateint startIndex = 0; ya&=UoI
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public PaginationSupport(List items, int sa8O<Ab
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totalCount){ yF)J7a:U
setPageSize(PAGESIZE); {P6Bfh7CZ
setTotalCount(totalCount); X)!XR/?
setItems(items); ytY\&m
setStartIndex(0); 9&*
7+!
} 7
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public PaginationSupport(List items, int 4C`RxQJM
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totalCount, int startIndex){ 5&8BO1V.
setPageSize(PAGESIZE); lWc[Q1
setTotalCount(totalCount); gg`{kN^r.a
setItems(items); qefp3&ls
setStartIndex(startIndex); 7SHllZ
} zh2<!MH
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public PaginationSupport(List items, int ^P9mJ:
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totalCount, int pageSize, int startIndex){ 9\Gk)0
setPageSize(pageSize); *R+M#l9D`
setTotalCount(totalCount); >IS4
setItems(items); y7pBcyWTE=
setStartIndex(startIndex); FC+-|1?C
} G
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publicList getItems(){ 8d*S9p,/
return items; diNSF-wi,,
} qK$O /g,
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publicvoid setItems(List items){ FZgf"XM>
this.items = items; K-]) RIM
} HBp??.r
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publicint getPageSize(){ ~EmK;[Z
return pageSize; ^JxVs
7
} j?C[ids<
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publicvoid setPageSize(int pageSize){ R7IFlQH%
this.pageSize = pageSize; <&[`
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} }*J04o$oI
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publicint getTotalCount(){ +ase>'<N#
return totalCount; z@UH[>^gj
} !QdX+y<re
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publicvoid setTotalCount(int totalCount){ JQ
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if(totalCount > 0){ V #vkj
this.totalCount = totalCount; L__{U_p
int count = totalCount / +9LzDH
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pageSize; EiD41N
if(totalCount % pageSize > 0) WMKxGZg"
count++; _H U>T
indexes = newint[count]; -ik$<>{X
for(int i = 0; i < count; i++){ }qGd*k0F0
indexes = pageSize * '~yxu$aK
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i; xTG5VBv
} ;]R5:LbXS
}else{ D|Tz{DRG
this.totalCount = 0; d?5oJ'JU
} mb_6f:Qh3
} YpZuAJm<2_
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publicint[] getIndexes(){ L5:1dF
return indexes; Md9y:)P@Y
} ?!"pzDg
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publicvoid setIndexes(int[] indexes){ v"Bm4+c&0
this.indexes = indexes; OGH,K'l
} |pknaz
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publicint getStartIndex(){ 1.,KN:qe
return startIndex; q(46v`u
} y'6l fThT
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publicvoid setStartIndex(int startIndex){ >C{8}Lg-.
if(totalCount <= 0) HOPl0fY$L
this.startIndex = 0; lV./K;\T
elseif(startIndex >= totalCount) Rm_+kp@\
this.startIndex = indexes butBS
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[indexes.length - 1]; b5~p:f-&4B
elseif(startIndex < 0) .i;?8?
this.startIndex = 0; Bs '=YK$
else{ mq}uq9<
this.startIndex = indexes .2|(!a9W
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[startIndex / pageSize]; =Y^K
} %"#ydOy
} bO('y@)X
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publicint getNextIndex(){ Om;`"5
int nextIndex = getStartIndex() + Yp3 y%n
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pageSize; '19?
if(nextIndex >= totalCount) %LqT>HXJ
return getStartIndex(); i}f" 'KW
else Ew;AYZX
return nextIndex; lN"@5(5%
} jW^]N$>
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publicint getPreviousIndex(){ EKuLt*a/
int previousIndex = getStartIndex() -
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pageSize; JCB3 BZg7&
if(previousIndex < 0) >%N,F`^3
return0; q&:%/?)x
else oZL# *Z(h
return previousIndex; lQRtsmZ0
} cUw$F{|W
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} Fl(j,B6Z
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抽象业务类 05jjLM'e
java代码: .WBp!*4
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/** @'Pay)P
* Created on 2005-7-12 xNRMI!yv
*/ <a+@4d;
package com.javaeye.common.business; W]>%*n
s._,IW;
import java.io.Serializable; fL-$wK<p<
import java.util.List; ]T.+(\I
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import org.hibernate.Criteria; /*"pylm
import org.hibernate.HibernateException; Vkf{dHjW
import org.hibernate.Session; I;UT;/E2
import org.hibernate.criterion.DetachedCriteria; _ib
@<%
import org.hibernate.criterion.Projections; e;|$nw-
import {DUtdu[
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org.springframework.orm.hibernate3.HibernateCallback; BJg
import h$6~3^g:P
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org.springframework.orm.hibernate3.support.HibernateDaoS |GP&!]
H%}/O;C
upport; 7y.iXe!P
LEX @hkh
import com.javaeye.common.util.PaginationSupport; {/,AMJ<:G]
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public abstract class AbstractManager extends B;piO-hH
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HibernateDaoSupport { W|s";EAM
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privateboolean cacheQueries = false; ekmWYQ
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privateString queryCacheRegion; Fw}|c
@tJic|)x
publicvoid setCacheQueries(boolean N8J(RR9O
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cacheQueries){ @*|T(068&
this.cacheQueries = cacheQueries; ;&O *KhLH
} 3Y&4yIx
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publicvoid setQueryCacheRegion(String _8\B~;0
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queryCacheRegion){ Tb8r+~HK
this.queryCacheRegion = TgHUH>k
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queryCacheRegion; ]IzD`
} .;l`VWP
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publicvoid save(finalObject entity){ qL[SwEc
getHibernateTemplate().save(entity); ,*?[Rg0]+
} 8Kk41 =
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publicvoid persist(finalObject entity){ Z/|=@gpw
getHibernateTemplate().save(entity); BL"7_phM,
} j0(jXAc;UB
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publicvoid update(finalObject entity){ DQaE9gmC
getHibernateTemplate().update(entity); }Gy M<!:
} ,xAF=t
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publicvoid delete(finalObject entity){ ErQ6a%~,
getHibernateTemplate().delete(entity); Xil;`8h
} !ab ef.%:
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publicObject load(finalClass entity, )?c,&
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finalSerializable id){ mVh;=>8K
return getHibernateTemplate().load bX`Gv+
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(entity, id); XD't)B(q
} i"
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publicObject get(finalClass entity, U~;tk@
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finalSerializable id){ ?( z"Ub]
return getHibernateTemplate().get N^@:+,<3
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(entity, id); J_m@YkK
} vLyazVj..
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publicList findAll(finalClass entity){ 7mMMVz2
return getHibernateTemplate().find("from cDE5/!
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" + entity.getName()); kxJ[Bi#
} _L$a[zH
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publicList findByNamedQuery(finalString 5b*knN>
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namedQuery){ h:r?:C>n
return getHibernateTemplate CH
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().findByNamedQuery(namedQuery); nJ
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} G9yK/g&q
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publicList findByNamedQuery(finalString query, _vDmiIn6K
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finalObject parameter){ :zPK
return getHibernateTemplate 2zW IB[
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().findByNamedQuery(query, parameter); " QiR
} DL1nD5
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publicList findByNamedQuery(finalString query, IDFzyg_
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finalObject[] parameters){ $D#h, `
return getHibernateTemplate vc&+qI+I3
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().findByNamedQuery(query, parameters); 6[c|14l
} C&MqH.K
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publicList find(finalString query){ tHZ"o!(S
return getHibernateTemplate().find MJ1qU}+]
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(query); H@?} !@
} QOSMV#Nw%
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publicList find(finalString query, finalObject -bzlp7q*
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parameter){ $5)#L$!,]
return getHibernateTemplate().find K4<"XF1A:
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(query, parameter); H~:oW~Ah
} Td'(RV
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public PaginationSupport findPageByCriteria C1=&Vm>g+
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(final DetachedCriteria detachedCriteria){ cr{yy :D
return findPageByCriteria }3X/"2SW^
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ;Jg$C~3tf
} $) "\N
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public PaginationSupport findPageByCriteria Mh-"B([Z
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(final DetachedCriteria detachedCriteria, finalint M?"4{
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startIndex){ w
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return findPageByCriteria RdWn =;
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(detachedCriteria, PaginationSupport.PAGESIZE, )__sw
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startIndex); >B**fZ~L
} mnK<5KLg1
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public PaginationSupport findPageByCriteria M*gvYo
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(final DetachedCriteria detachedCriteria, finalint C78g|n{
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pageSize, (c0L
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finalint startIndex){ K
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return(PaginationSupport) >ceC8"}J5M
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getHibernateTemplate().execute(new HibernateCallback(){ uD=Kar
publicObject doInHibernate V4V`0I
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(Session session)throws HibernateException { vkTu:3Qe
Criteria criteria = {L7Pha
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detachedCriteria.getExecutableCriteria(session); 3Jizv,?
int totalCount = 5WHz_'c
\{ EVRRXn
((Integer) criteria.setProjection(Projections.rowCount 'fU #v`i
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()).uniqueResult()).intValue(); /e>%yq<9B
criteria.setProjection #U`AK9rP_g
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a{);
(null); -z`FKej
List items = IN bV6jZL
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criteria.setFirstResult(startIndex).setMaxResults zb9G&'7
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(pageSize).list(); MN2i0!+
PaginationSupport ps = =|E
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new PaginationSupport(items, totalCount, pageSize, r
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startIndex); zJw5+
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return ps; 88_ef7w
} .?6p~
}, true); .|[{$&B
} VNWB$mM.2
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public List findAllByCriteria(final gd0)s1{9
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DetachedCriteria detachedCriteria){ 4u}Cki,vOK
return(List) getHibernateTemplate LhLAQ2~
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().execute(new HibernateCallback(){ +I3Vfv
publicObject doInHibernate Zu|NF
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(Session session)throws HibernateException { I^k&v V
Criteria criteria = zG_n x3
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detachedCriteria.getExecutableCriteria(session); 7!AyL w
return criteria.list(); 2@tnOs(*
} V _~lME
}, true); ]6Iu\,#J
} N0S^{j,i
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public int getCountByCriteria(final b+qd'
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DetachedCriteria detachedCriteria){ l3Zi]`@r
Integer count = (Integer) MBt\"b#t
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getHibernateTemplate().execute(new HibernateCallback(){ [>v1JN
publicObject doInHibernate yx|iZhK0:}
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(Session session)throws HibernateException { ^ l#6Es
Criteria criteria = VVSt,/SO
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detachedCriteria.getExecutableCriteria(session); 2om:S+3)2
return m)L50ot:/
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criteria.setProjection(Projections.rowCount 5c::U=
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()).uniqueResult(); +ytP5K7
} f\oW<2k]~
}, true); 'zm5wqrkAd
return count.intValue(); Q8`V0E\~
} %}TJr]'F
} nlB'@r
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用户在web层构造查询条件detachedCriteria,和可选的 R-m5(
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 _3%$E.Q
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PaginationSupport的实例ps。 +m./RlQ{
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ps.getItems()得到已分页好的结果集 v K{2
ps.getIndexes()得到分页索引的数组 [z!m
ps.getTotalCount()得到总结果数 Ew0)MZ.#
ps.getStartIndex()当前分页索引 YT8q0BR]
ps.getNextIndex()下一页索引 h.R46 :
ps.getPreviousIndex()上一页索引 5!A:xV]6]
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 *e [*
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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 ykbfK$jz
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一下代码重构了。 xKE=$SV(
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我把原本我的做法也提供出来供大家讨论吧: VB90 5%
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首先,为了实现分页查询,我封装了一个Page类: 1y:fH4V
java代码: =LLpJ+
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/*Created on 2005-4-14*/ ?<.a>"!
package org.flyware.util.page; Sydl[c pH$
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/** v\bWQs1
* @author Joa @$kO7k0{g
* `#iL'ND[
*/ uq[5 om"
publicclass Page { rF[-4t
%
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/** imply if the page has previous page */ #tg\
bb
privateboolean hasPrePage; F^{31iU~CX
g~-IT&O
/** imply if the page has next page */ '2Zs15)V
privateboolean hasNextPage; L44|/~
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/** the number of every page */ =U~53Tg
privateint everyPage; -flcB|I`
&;?+ ^L>
/** the total page number */ *\#<2 QAe
privateint totalPage; ,5<AV K-#Q
=LIb0TZ2
/** the number of current page */ PdVY tK%
privateint currentPage; 6?5dGYAX<
E8PwA.
/** the begin index of the records by the current z l`m1k-X
mI<s f?.
query */ CB9:53zK9
privateint beginIndex; shdzkET8N
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/** The default constructor */ ZYY~A_C
public Page(){ ye(av&Hn
h3E}Sa(MQ:
} IHCxM|/k(M
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/** construct the page by everyPage lAG@nh^
* @param everyPage n|WSnm,W
* */ \H>Psv{
public Page(int everyPage){ 2A|mXWG}~
this.everyPage = everyPage; )$1j"mV
} }LS.bQKqi,
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/** The whole constructor */
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public Page(boolean hasPrePage, boolean hasNextPage, (bsywM
x ]}'H
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int everyPage, int totalPage, $s
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int currentPage, int beginIndex){ P()n=&XO6
this.hasPrePage = hasPrePage; n>B
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this.hasNextPage = hasNextPage; *1-0s*T
this.everyPage = everyPage; "fv+}'
this.totalPage = totalPage; F5H*z\/={
this.currentPage = currentPage; ?HOnDw.v1
this.beginIndex = beginIndex; {=Ji2k0U'
} G3!O@j!7w$
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/** "WmsBdO
* @return \Js*>xA
* Returns the beginIndex. N`,,sw
*/ Hr]
publicint getBeginIndex(){ +3AX1o%p,#
return beginIndex; -sf[o"T,j
} Q A~F
/_expSPHl
/** >(YH@Z&;
* @param beginIndex 4/\Ynb.L
* The beginIndex to set. :qR8 e J
*/ @o}J )
publicvoid setBeginIndex(int beginIndex){ 9' H\-
this.beginIndex = beginIndex; L`O7-'`
} 45Zh8 k
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/** >}0H5Q8@
* @return Kx[+$Qt
* Returns the currentPage. Yc)Dx3
*/ .2rpQa/h
publicint getCurrentPage(){ RxPD44jVA
return currentPage; l.;^w
} -y_q
wUg=jnY
/** #U3q
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* @param currentPage N48X[Q*
* The currentPage to set. y fuH
*/ 0[uOKFgE
publicvoid setCurrentPage(int currentPage){ *U\`HUW
this.currentPage = currentPage; +g1+,?cU
} aAd1[?&
FL$S_JAw
/** o?= &kx
* @return #IqRu:csp
* Returns the everyPage. %bdBg
*/ !-SI &qy
publicint getEveryPage(){ e !w{ap8u
return everyPage; 6I_4{
} Y)GU{
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/** oj?y_0}:^
* @param everyPage ^x(s!4d]
* The everyPage to set. YiL^KK
*/ 6 RSit
publicvoid setEveryPage(int everyPage){ j@UE#I|h
this.everyPage = everyPage; '['x'G50
} ?d3<GhzlR3
VS~+W=5}
/** ?aB%h
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* @return cnY}^_
* Returns the hasNextPage. (v0Q.Q@<
*/ 5VVU%STP
publicboolean getHasNextPage(){ u<Ch]m+
return hasNextPage; MQ'=qR
} N
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]h`d>#Hw!
/** 11 A$#\,
* @param hasNextPage (II#9n)
* The hasNextPage to set. 79jnYjk
*/ QPFv]^s(
publicvoid setHasNextPage(boolean hasNextPage){ :8v? 6Q
this.hasNextPage = hasNextPage; @y
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} bXM&VW?OP
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/** ['6Sq@c)
* @return m.5@qmQ
* Returns the hasPrePage. u@Z6)r'
*/ h>z5m
publicboolean getHasPrePage(){ X7?14W
return hasPrePage; wr>6Go%
} gla'urb[i|
Io/;+R.
/** tI.ho
* @param hasPrePage .\
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* The hasPrePage to set. S[l z>I
*/ w`/~y
publicvoid setHasPrePage(boolean hasPrePage){ h54\
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this.hasPrePage = hasPrePage; .F\[AD 5
} }h sR}
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/** 0yb9R/3.
* @return Returns the totalPage. A'n7u'6=
* wj Kc!iB
*/ Q[T)jo,j%
publicint getTotalPage(){ T-js*
return totalPage; c11;(
} !G'wC0
qzu(4*Gk6
/** )L"J?wTe
* @param totalPage [XP\WG>s
* The totalPage to set. W$gjcsv
*/ @k-GyV-v
publicvoid setTotalPage(int totalPage){ [| C
this.totalPage = totalPage; T!1XL7
} Ud#xgs'
8K\S]SZ
} 8xoC9!xt
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aMxM3"
Yg;7TKy
HoZsDs.XZ
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
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E8aD[j[w
个PageUtil,负责对Page对象进行构造: fz+dOIU3\L
java代码: C&.Q|S2_
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1[e%E#h
/*Created on 2005-4-14*/ tR?)C=4,
package org.flyware.util.page; %)o;2&aD
J(,{ -d-E
import org.apache.commons.logging.Log; 1E$^ul-v
import org.apache.commons.logging.LogFactory; Et&PzDvU
U@LIw6B!KL
/** #0Z%4W Q
* @author Joa q9nQ/]rkHF
* `pd+as
*/ 5^N`~
publicclass PageUtil { bZgFea_>i
c:-n0m'i
privatestaticfinal Log logger = LogFactory.getLog 3AcDW6x|
I\=&v^]
(PageUtil.class); YG#{/;^nm)
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/** tG0
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* Use the origin page to create a new page VB=jKMi
* @param page Bdib)t[
* @param totalRecords z2;<i|Ez0
* @return k.%FGn'fR
*/ io7Zv*&T0
publicstatic Page createPage(Page page, int Ro#O{
p'=XW#2 >
totalRecords){ ]!WD">d:
return createPage(page.getEveryPage(), =^w:G =ymS
M{X; H'2
page.getCurrentPage(), totalRecords); L#MMNc+
} is{H >#+"
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/** ezhK[/E=
* the basic page utils not including exception t'HrI-x
Nkk+*(Z
handler &C6*"JZ4
* @param everyPage }`_x%]EJ
* @param currentPage L ?S#3@Pa
* @param totalRecords Ne}x(uRn
* @return page .s3y^1C
*/ 2Jt*s$
publicstatic Page createPage(int everyPage, int 9@YhAj
y+M9{[ i/O
currentPage, int totalRecords){ +QEiY~i
everyPage = getEveryPage(everyPage); Q\z9\mMG-
currentPage = getCurrentPage(currentPage); w[/m:R?eX
int beginIndex = getBeginIndex(everyPage, UQJ
(6i.>%|_
currentPage); Gi,4PD-ro
int totalPage = getTotalPage(everyPage, @E?o~jO(e
B?;P:!/1
totalRecords); ;<BMgO}N
boolean hasNextPage = hasNextPage(currentPage, OJ<V<=MYZ
P"Y7N?\](
totalPage); LbnW(wr6:(
boolean hasPrePage = hasPrePage(currentPage); f+4j ^y}
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returnnew Page(hasPrePage, hasNextPage, ZY8:7Q@P>
everyPage, totalPage, uVzvUz{b
currentPage, h:<?)g~U
b4>1UZGW-
beginIndex); qyR}|<F8*
} d{(NeT s
t:tIzFNv
privatestaticint getEveryPage(int everyPage){ }}zY]A
return everyPage == 0 ? 10 : everyPage; f
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} azl!#%
Z4D[nPm$
privatestaticint getCurrentPage(int currentPage){ i:
VMCNH
return currentPage == 0 ? 1 : currentPage; QJU\YH%}
} SF[}suL
u Qz!of%x
privatestaticint getBeginIndex(int everyPage, int fmv,)UP
i?'|}tK
currentPage){ '_FxxLAO
return(currentPage - 1) * everyPage; lZ?YyRsa6&
} e}TDo`q
Z8\/Fb
privatestaticint getTotalPage(int everyPage, int %ZGG6Xgw
@8lT*O2j
totalRecords){ Er<!8;{?
int totalPage = 0; {EyWSf"
a[NR%Xq
if(totalRecords % everyPage == 0) sv+6#
totalPage = totalRecords / everyPage; k;l^y%tzp
else *)s^+F 0
totalPage = totalRecords / everyPage + 1 ; h.5KzC
S
}[SYWJIc
return totalPage; Z~ u3{
} QNGp+xUHJ9
!twYjOryH[
privatestaticboolean hasPrePage(int currentPage){ _tpOVw4I
return currentPage == 1 ? false : true; 3|4<SMm
} | *N;R+b
6T%5<I*&3s
privatestaticboolean hasNextPage(int currentPage, pg{cZ1/
\hg%J/
int totalPage){ N, 4hh?
return currentPage == totalPage || totalPage == >YR2h/S
1Hs'YzvY
0 ? false : true; gPIl:, d(
} "pc
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tg
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} L$v<t/W
,91 n
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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。 :}-izd)/j
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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 &!B4v<#, U
ba^/Ar(B
做法如下: s\0,@A
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 \f@obp
XC4wm#R
的信息,和一个结果集List: +NVXFjPC
java代码: -Sa-eWP
ywA7hm
L9d|7.b
/*Created on 2005-6-13*/ 5 hW#BB
package com.adt.bo; ]rji]4s
&FWz7O>1
import java.util.List; y:Aha#<
K?>sP%m)
import org.flyware.util.page.Page; %JI*)K1WI
vb3hDy
/** |\W~+}'g~
* @author Joa fpJ%{z2
*/ jtgj h\Nt
publicclass Result { +%Z:k
dnkHx
private Page page; JA4}Bwn
LQV&;O4'
private List content; nX8ulGG s
0bOT&Z^
/** C$4{'J-ZH
* The default constructor "bz]5c~
*/ t+D= @"BZP
public Result(){ cUn>gT
super(); `nY.&YT
} l[C_vUg
lv+:
`
/** )nrYxxN
* The constructor using fields 5..YC=_20
* \\3 ?ij:v
* @param page 9+ |W;
* @param content Z/d {v:)
*/ [}l#cG6 k
public Result(Page page, List content){ W)8Pq9Hnv
this.page = page; AuZISb%6
this.content = content; KyBtt47\
} D[)_
f
n%Oq"`w4
/** v#e*RI2}
* @return Returns the content. )Br#R:#
*/ x=kJlGT
publicList getContent(){ 9 9^7Ek!z#
return content; g |H
} #qv!1$}2
u"m TS&
/** *$Zy|&[Z
* @return Returns the page. &.qLE
*/ AnK X4Q
public Page getPage(){ HE>V\+
AL
return page; CeM%?fr5
} DuLl"w\_@
q(A_k+NL
/** HZ1 nuA
* @param content t<`d*M2w
* The content to set. "c.-`1,t
*/ ;aD?BD__Z
public void setContent(List content){ Fk9]u^j
this.content = content; 1
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} DQ9aq.;
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/** Y#6LNI
* @param page 2p4iir
* The page to set. lJ,\^\q
*/ <j/wK]d*/
publicvoid setPage(Page page){ ~z")';I|
this.page = page; xM@s`s|n
} !;P[Y"h@r
} MWK)Bn
+KWO`WR
N(3Bzd)
[j0jAl
sH'0utD#Y
2. 编写业务逻辑接口,并实现它(UserManager, Ro4!y:2|
)u4=k(
UserManagerImpl) 72_+ b
java代码: _18Z]XtX
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4bL? V^@7
/*Created on 2005-7-15*/ u J]uz%
package com.adt.service; BOP7@ D
6y57m;JW/
import net.sf.hibernate.HibernateException; 0)7v_|z
2aX$7E?
import org.flyware.util.page.Page; ]w0Y5H "
N eP
import com.adt.bo.Result; p=#/H,2
&9z`AY]>
/** h9!4\{V;h
* @author Joa qnnRS
*/ 7oc Ng
publicinterface UserManager { /-t!)_zvw
2I& dTxIa
public Result listUser(Page page)throws BE],PCpPr
5rc3jIXc{|
HibernateException; y?A*$6
EyA(W;r.
} &4#%xg
+nim47
G2 V$8lh
i)$+#N
>j*0fb!:]
java代码: F9d6#~
zAvI f
VS_\bIC
/*Created on 2005-7-15*/ ZNpC&
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package com.adt.service.impl; aY;34SF
fe"w--v
import java.util.List; !0UfX{.
mwN"Cu4t
import net.sf.hibernate.HibernateException; 9`5.0**
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import org.flyware.util.page.Page; ( ]0F3@k#s
import org.flyware.util.page.PageUtil; (Q
^=^s|
`ZO5-E
import com.adt.bo.Result; 9C{Xpu
import com.adt.dao.UserDAO; gB+CM?
LKq
import com.adt.exception.ObjectNotFoundException; |id7@3leu
import com.adt.service.UserManager; ;-l^X%r
lw?C:-m
/** RBg2iG$8|
* @author Joa ;`kOFg#`)c
*/ &B=z*m
publicclass UserManagerImpl implements UserManager { TiZ
MY:^
2n2,MB
private UserDAO userDAO; _ouZd.
odJE~\\hw
/** -*Qg^1]i+
* @param userDAO The userDAO to set. (^sb('"
*/ +u t%C.1
publicvoid setUserDAO(UserDAO userDAO){ dS \n2Qb
this.userDAO = userDAO; T nyLVIP
} NwQ$gDgu t
K|6}g7&X
/* (non-Javadoc) s>WqVuXmn
* @see com.adt.service.UserManager#listUser S$R=!3* "V
fIatp
(org.flyware.util.page.Page) YnDaBpx
*/ (Ia:>ocE0
public Result listUser(Page page)throws D62'bFB^
^YfAsBs&
HibernateException, ObjectNotFoundException { 7Wiwnv_"
int totalRecords = userDAO.getUserCount(); B>z^W+Unyn
if(totalRecords == 0) sk0/3X*Q%
throw new ObjectNotFoundException XRyeEwA;pp
7)Tix7:9S;
("userNotExist"); \,:7=
page = PageUtil.createPage(page, totalRecords); t*6C?zEAU
List users = userDAO.getUserByPage(page); LUz`P6
returnnew Result(page, users); 9c1q:>|
} YY'[PXP$Y
3=UufI
}
>Yv#t.!
"/UPq6
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^BI&-bR@
Yx ;j
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 AP=SCq;
o(t`XE['<
询,接下来编写UserDAO的代码: AO5a
3. UserDAO 和 UserDAOImpl: *S4&V<W>
java代码: o5Knot)Oy
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:B3W
Gt !Hm(
/*Created on 2005-7-15*/ Tilr%D(Q
package com.adt.dao; <!|=_W6
y %Y P
import java.util.List; *1>T c,mb
7bJM
$
import org.flyware.util.page.Page; ~n/:a
: R8+jO
import net.sf.hibernate.HibernateException; xelh!AtE
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/** o
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* @author Joa X<1ymb3
*/ ^4saB+qm
publicinterface UserDAO extends BaseDAO { `X`|]mWj
%]O#t<D
publicList getUserByName(String name)throws #KtV 4)(
dsbz\w3:
HibernateException; ab 6D &
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publicint getUserCount()throws HibernateException; $,T3vX]<
/J,&G:
Er
publicList getUserByPage(Page page)throws RZj06|r8
6|%HCxWO
HibernateException; D,uT#P
\l 3M\$oS>
} &0-Pl.M
ayA_[{j%X
9AQ2FD
eA/}$.R
G&7 } m
java代码: Gs}lw'pK
z&[[4[
q0\$wI
/*Created on 2005-7-15*/ .q$/#hN:e
package com.adt.dao.impl; +T7FG_
,k/<Nv;
import java.util.List; _LZ 442
/B
import org.flyware.util.page.Page; "S&1J8D|
]g9n#$|.
import net.sf.hibernate.HibernateException; ;{cl*EN
import net.sf.hibernate.Query; jTY{MY Jh
P99s
import com.adt.dao.UserDAO; 11yS2D
N/AP8
/** *K w/ilI
* @author Joa w~*"mZaG
*/ DZ|/#- k
public class UserDAOImpl extends BaseDAOHibernateImpl 8m)E~6
oRCD8b?
implements UserDAO { |n&EbOmgf
Z?'){\$*
/* (non-Javadoc) woK?td|/
* @see com.adt.dao.UserDAO#getUserByName ia/_61%
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(java.lang.String) z3-AYQ.H
*/ cV)~%e/
publicList getUserByName(String name)throws YyR~pT#ffT
%bUpVyi!(
HibernateException { J)Td'iT(
String querySentence = "FROM user in class =p';y&
,cFp5tV$
com.adt.po.User WHERE user.name=:name"; SYTzJK@vZJ
Query query = getSession().createQuery -n'%MT=Cd
^zaN?0%S33
(querySentence); :YZMRJL
query.setParameter("name", name); aG\B?pn-
return query.list(); bwh.ekf8
} |4a#O8d
ub]
w"N
/* (non-Javadoc) YEqWTB|w
* @see com.adt.dao.UserDAO#getUserCount() (wIpq<%
*/ v4Q8RE?
publicint getUserCount()throws HibernateException { c
=i6
int count = 0; \D
#NO
String querySentence = "SELECT count(*) FROM nEm+cHHo?
89)rss
user in class com.adt.po.User"; SLc'1{
Query query = getSession().createQuery +<H)DPG<
W;C41>^?/
(querySentence); Oj0/[(D-
count = ((Integer)query.iterate().next [e'Ts#($A
u|D_"q~+6
()).intValue(); I(Yyg,1Z
return count; *^u5?{$l(
} Tce2]"^;
y(8AxsROp
/* (non-Javadoc) 6^.<