Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 YR.'JF`C
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 'a*IZb-M
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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 }YO}LQ-|
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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 PEl]HI_H
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分页支持类: M3kE91
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java代码: #!Fs[A5%
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package com.javaeye.common.util; =1qkoc~
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import java.util.List; MzG.Qh'z
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publicclass PaginationSupport { O=/Tx2i;
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publicfinalstaticint PAGESIZE = 30; rl=_ "sd=
@~ L.m}GF
privateint pageSize = PAGESIZE; 5ntP{p%>
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privateList items; k5YDqGn'q
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privateint totalCount; Fu/CX4R_|
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privateint[] indexes = newint[0]; ffVYlNQ7L
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privateint startIndex = 0; cD6o8v4]]
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public PaginationSupport(List items, int urB.K<5ZA
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totalCount){ 2<|5zF
setPageSize(PAGESIZE); m}(DJ?qP
setTotalCount(totalCount); G#Ow>NJ
setItems(items); 0l6%[U?o
setStartIndex(0); ]Y?$[+Y
} aRmS{X3
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public PaginationSupport(List items, int 10&A3C(E
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totalCount, int startIndex){ Q~kwUZ
setPageSize(PAGESIZE); u4'Lm+&O
setTotalCount(totalCount); uJ$,e5q
setItems(items); z4goa2@Z
setStartIndex(startIndex); G`z48
} P+SCX#{y
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public PaginationSupport(List items, int AUK7a
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totalCount, int pageSize, int startIndex){ )C@,mgh
setPageSize(pageSize); Nvi14,q/
setTotalCount(totalCount); 4C:YEX~
setItems(items); Q8n?7JB
setStartIndex(startIndex); ^9nM)[/C?
} 2,\uY}4
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publicList getItems(){ pqK3u)
return items; u$"5SGI6
} s"/8h#!zv
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publicvoid setItems(List items){ ^:#%TCJ
this.items = items; pLU>vQA
} F\e'z
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publicint getPageSize(){ &,/T<V
return pageSize; @'<|B. f
} 82vx:*Ip!}
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publicvoid setPageSize(int pageSize){ /d4xHt5a
this.pageSize = pageSize; P<hqr;
} -~q]0>
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publicint getTotalCount(){ R&QT
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return totalCount; TwN8|ibVmP
} vBp5&*
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publicvoid setTotalCount(int totalCount){ I2dt#
if(totalCount > 0){
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this.totalCount = totalCount; 'K1w.hC<
int count = totalCount / =aCv
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pageSize; Wac8x%J
if(totalCount % pageSize > 0) !m;VWGl*
count++; 2g$Wv :E3
indexes = newint[count]; K6X1a7
for(int i = 0; i < count; i++){ j405G4BVW
indexes = pageSize * vcmS]$}
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} .UcS4JU
}else{ y+PukHY
this.totalCount = 0; 4u&doSXR
} ,-b9:]{L
} BhKxI
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publicint[] getIndexes(){ /vhh2`
return indexes; ax<0grK
} [Y*UCFhI0
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publicvoid setIndexes(int[] indexes){ QUNsS9
this.indexes = indexes; L*Y}pO
} )Mok$
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publicint getStartIndex(){ efhwbn
return startIndex; |'.SOm9)*
} )_jO8)jB
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publicvoid setStartIndex(int startIndex){ Cw_<t
if(totalCount <= 0) _RmrjDk
this.startIndex = 0; c"~TH.,d
elseif(startIndex >= totalCount) r oKiSE`
this.startIndex = indexes y.nw6.`MR
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[indexes.length - 1]; ^j`
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elseif(startIndex < 0) >M!>Hl/
this.startIndex = 0; \ Q6Ip@?
else{ WO{N@f^
this.startIndex = indexes T \A uL
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[startIndex / pageSize]; zumRbrz
} M3Z yf
} 6k[u0b`
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publicint getNextIndex(){ TwH(47|?Nt
int nextIndex = getStartIndex() + ,9rT|:N
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pageSize; K.%E=^~q
if(nextIndex >= totalCount) :J"e{|g',
return getStartIndex(); HCu1vjU(]
else UYPBKf]A9
return nextIndex; MMf6QxYf
} z TK
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publicint getPreviousIndex(){ \u*,~J)z
int previousIndex = getStartIndex() - !y),| #7P
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pageSize; NE! Xt <A
if(previousIndex < 0) +)Ty^;+[1
return0; YT_kMy>
else 2::T, Z
return previousIndex; @iaN@`5I6s
} N>~*Jp2;
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} nuQ"\ G
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抽象业务类 1#@'U90xf
java代码: }QI*Ns
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/** &K4o8Qz
* Created on 2005-7-12 vhg4E80Kr
*/ /Iskjcc60W
package com.javaeye.common.business; i.<}X
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import java.io.Serializable; brFOQU?
import java.util.List; 6!'yU=Z`
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import org.hibernate.Criteria; }}]Y mf
import org.hibernate.HibernateException; F-X>|oK>z
import org.hibernate.Session; mZ5UaSG
import org.hibernate.criterion.DetachedCriteria; rS
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import org.hibernate.criterion.Projections; 4qMHVPJv\
import ge`J>2
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org.springframework.orm.hibernate3.HibernateCallback; V *]!N
import %>bwpN
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org.springframework.orm.hibernate3.support.HibernateDaoS qg|+BIiUz
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upport; t_N
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import com.javaeye.common.util.PaginationSupport; A(uN=r@O
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public abstract class AbstractManager extends v6rw.
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HibernateDaoSupport { HP8pEo0Y
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privateboolean cacheQueries = false; C{Zv.+F
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privateString queryCacheRegion; L`!sV-.
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publicvoid setCacheQueries(boolean 0uvL,hF
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cacheQueries){ jlB3BwG{w
this.cacheQueries = cacheQueries; ^KlOD_GN|
} h~1QmEat
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publicvoid setQueryCacheRegion(String &><`?
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queryCacheRegion){ #Z.JOwi
this.queryCacheRegion = $DVy$)a!u
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queryCacheRegion; M}vPWWcl
} 4 A<c@g2
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publicvoid save(finalObject entity){ zknD(%a
getHibernateTemplate().save(entity); cnsGP*w
} =_86{wlk
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publicvoid persist(finalObject entity){ w5;EnI
getHibernateTemplate().save(entity); Z`%;bP:
} l{R)yTO
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publicvoid update(finalObject entity){ aZ^lI
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getHibernateTemplate().update(entity); )ad-s
} w7C=R8^
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publicvoid delete(finalObject entity){ IIPf5
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getHibernateTemplate().delete(entity); Ob+&!XTp?0
} 9f@)EKBK
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publicObject load(finalClass entity, +u#x[xO
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finalSerializable id){ 3)ip@29F
return getHibernateTemplate().load t|q=NK/
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(entity, id); :Ls36E8f=
} DkIkiw{L
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publicObject get(finalClass entity, RoTT%c P_
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finalSerializable id){ \5Jv;gc\\
return getHibernateTemplate().get %F~
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(entity, id); ^#o.WL%4/B
} ka*UyW}
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publicList findAll(finalClass entity){ _=MWt_A '3
return getHibernateTemplate().find("from by<2hLB9Q
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" + entity.getName()); UO wNcY
} EkX6> mo
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publicList findByNamedQuery(finalString -%.V0=G(Z
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namedQuery){ 2Kidbf
return getHibernateTemplate k-U/x"Pl
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().findByNamedQuery(namedQuery); JF
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} >MT)=4
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publicList findByNamedQuery(finalString query, Ce:ds%
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finalObject parameter){ xh0A2bw'OP
return getHibernateTemplate O^#u%/
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().findByNamedQuery(query, parameter); i`qh|w/b_
} B^9 #X5!
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publicList findByNamedQuery(finalString query, H~Cfni;
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finalObject[] parameters){ R.N*G]K5
return getHibernateTemplate JyO lVs<T
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().findByNamedQuery(query, parameters); |xm|Q(PG
} I>aa'em
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publicList find(finalString query){ 1tdCzbEn+
return getHibernateTemplate().find pZxL?N!
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(query); Z&,}Fgl!F
} x3|'jmg
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publicList find(finalString query, finalObject Y=Qf!Cq]
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parameter){ 8BDL{?Mu
return getHibernateTemplate().find 99K+7G\{
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(query, parameter); [[Z>(d$8
} B:cOcd?p
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public PaginationSupport findPageByCriteria W?-BT >#s
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(final DetachedCriteria detachedCriteria){ JxJ ntsn
return findPageByCriteria ^ {f^WL=
8[;oUVb5
(detachedCriteria, PaginationSupport.PAGESIZE, 0); D|9fHMg%
} :* b4/qpYv
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public PaginationSupport findPageByCriteria tL{~O=
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(final DetachedCriteria detachedCriteria, finalint Y{RB\}f(
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startIndex){ W+e*(W|d6
return findPageByCriteria TZNgtR{q
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(detachedCriteria, PaginationSupport.PAGESIZE, .+}o'rU
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startIndex); 389.&`Q%Ut
} a] =\h'S
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public PaginationSupport findPageByCriteria 92VX5?Cyg
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(final DetachedCriteria detachedCriteria, finalint 2 _n*u^X:_
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pageSize, Lo E(W|nj
finalint startIndex){ 2Q|*xd4B^
return(PaginationSupport) oh0|2IrM
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getHibernateTemplate().execute(new HibernateCallback(){ AO$PuzlLh
publicObject doInHibernate Juqn
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(Session session)throws HibernateException { hRIS[#z;U
Criteria criteria = Ej09RO"pB
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detachedCriteria.getExecutableCriteria(session); w })Pedg
int totalCount = xWz;5=7a]
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((Integer) criteria.setProjection(Projections.rowCount XqS*;Zj0
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()).uniqueResult()).intValue(); ZQ-`l:G
criteria.setProjection k5QD5/Ej
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(null); kJi&9
List items = ivz9R'
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criteria.setFirstResult(startIndex).setMaxResults 2vdQ&H4
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(pageSize).list(); |4> r"
PaginationSupport ps = R|J>8AL}BY
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new PaginationSupport(items, totalCount, pageSize, fw v
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startIndex); +M
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return ps; J*~2:{=%
} gq_7_Y/
}, true); j /dE6d
} *RbOQ86vP
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public List findAllByCriteria(final &Dg)"Xji
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DetachedCriteria detachedCriteria){ _O)2
return(List) getHibernateTemplate `I vw`} L
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().execute(new HibernateCallback(){ acYoOW1G
publicObject doInHibernate *- IlF]
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(Session session)throws HibernateException { k CW!m
Criteria criteria = Hdbnb[e
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detachedCriteria.getExecutableCriteria(session); r]JC~{
return criteria.list(); ?F87C[o
} $dZ>bXUw:
}, true); ^0x.'G?
} L>~@9a\jO
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public int getCountByCriteria(final XAU_SPAjiw
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DetachedCriteria detachedCriteria){ {GQ
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Integer count = (Integer) H#|Z8^ *Ds
}}``~
getHibernateTemplate().execute(new HibernateCallback(){ ZO%fS'n
publicObject doInHibernate (o*e<y,}W
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(Session session)throws HibernateException { B3cf] S%
Criteria criteria = }c35FM,
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detachedCriteria.getExecutableCriteria(session); @[5_C?2
return o%Uu.P
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criteria.setProjection(Projections.rowCount |.Nr.4Yp
@~$F;M=.*
()).uniqueResult(); N#RD:"RS!
} 'NT#(m%
}, true); pcRF:~TE
return count.intValue(); l$qStL*8O
} 2AXF$YjY
} <ELziE~>V
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用户在web层构造查询条件detachedCriteria,和可选的 #$rf-E5g-K
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 C
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PaginationSupport的实例ps。 Xzx[C_G
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ps.getItems()得到已分页好的结果集 oF%^QT"R
ps.getIndexes()得到分页索引的数组 Ud>`@2
ps.getTotalCount()得到总结果数 $:f.Krj
ps.getStartIndex()当前分页索引 H o4B
ps.getNextIndex()下一页索引 0M#N=%31
ps.getPreviousIndex()上一页索引 2j8Cv:{Nn%
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 f*{M3"$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 3xBN10R#
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一下代码重构了。 \#
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我把原本我的做法也提供出来供大家讨论吧:
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首先,为了实现分页查询,我封装了一个Page类: xM% H~(
java代码: _TZW|Dh-2F
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/*Created on 2005-4-14*/ "(0oP9lZ
package org.flyware.util.page; C}Rs[
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/** |)^clkuGX
* @author Joa <Cu'!h_nL
* zXQVUhL6
*/ CIIY|DI`l
publicclass Page { vkd *ER^
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/** imply if the page has previous page */ D._{E*vg
privateboolean hasPrePage; {V.Wk
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/** imply if the page has next page */ a4%`"
privateboolean hasNextPage; .H ,pO#{;
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/** the number of every page */ v,n);
privateint everyPage; R_maNfS]Z
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/** the total page number */ jz|VF,l
privateint totalPage; ,cLH*@
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/** the number of current page */ x,w8r+~5
privateint currentPage; YmOldR9v(
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/** the begin index of the records by the current %yeu"
{ AFf:[G
query */ Ocyb c%
privateint beginIndex; 1bd$XnU
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/** The default constructor */ =`JW1dM
public Page(){ z23#G>I&
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} 3eWJt\}?B
]}.0el{
/** construct the page by everyPage N=q#y@ L
* @param everyPage /\d(c/, 4
* */ kY=rz&?U
public Page(int everyPage){ >d#3|;RY
this.everyPage = everyPage; B&
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} >}CEN
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/** The whole constructor */ ^}hJL7O'
public Page(boolean hasPrePage, boolean hasNextPage, =)(0.E
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int everyPage, int totalPage, RB IOdz
int currentPage, int beginIndex){ qIz}$%!A
this.hasPrePage = hasPrePage; g
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this.hasNextPage = hasNextPage; i@XB&;*c\
this.everyPage = everyPage; ##v`(#fu
this.totalPage = totalPage; VNO'="U
this.currentPage = currentPage; VtWT{y5Ec
this.beginIndex = beginIndex; R#ya,L
} &8n?
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/** Ev{MCu1!6
* @return iy}xICt
* Returns the beginIndex. x)_r@l`$ix
*/ ioWo ]
publicint getBeginIndex(){ dZDK7UL
return beginIndex; T<6GcI>A
} 0p `")/
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/** xG1?F_]
* @param beginIndex I|T7+{5z
* The beginIndex to set. l!:^6i
*/ kM;o0wi
publicvoid setBeginIndex(int beginIndex){ ('JKN"3
this.beginIndex = beginIndex; xp^ 7#`MJ?
} e1UITjy
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/** toIYE*ocv=
* @return !W
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* Returns the currentPage. A?r^V2+j
*/ 'g hys1H
publicint getCurrentPage(){ VX!hv`E
return currentPage; :BD>yOlG
} K"w%n[u)
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/** ,rai%T/rL
* @param currentPage I0_Ecp
* The currentPage to set. ~j"3}wXc5
*/ 'fn$'CeM(
publicvoid setCurrentPage(int currentPage){ WqQU@sA
this.currentPage = currentPage; (v^Z BM_
} "mA1H]r3
+>}o;`hPe
/** R$d7\nBG
* @return p/&HUQQk
* Returns the everyPage. P0 b4Hq3
*/ ({ k7#1
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publicint getEveryPage(){ jkt6/H
return everyPage; $@.jZ_G
} i?-Y
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/** r]T0+ oQ>
* @param everyPage T,OS 0;7O
* The everyPage to set. !^?qU;|
*/ RG1\=J$:E
publicvoid setEveryPage(int everyPage){ CmHyAw(
this.everyPage = everyPage; `{o$F ::(
} RG}}Oh="v
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/** d}+W"j;
* @return :c:V%0Yji
* Returns the hasNextPage. .&|L|q}
*/ WFDCPQ@
publicboolean getHasNextPage(){ 7&|6KN}c
return hasNextPage; <u0,Fp
} n[CoS
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/** y/tSGkMv
* @param hasNextPage 7n&yv9"
* The hasNextPage to set. p+ Lv=e)0u
*/ 2*'ciH37
publicvoid setHasNextPage(boolean hasNextPage){ ]0-<>
this.hasNextPage = hasNextPage; z_n\5.
}
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/** 5v|EAjB6o
* @return =
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* Returns the hasPrePage. taDQ65
*/ X 8R1a?
publicboolean getHasPrePage(){ pkk4h2Ah
return hasPrePage; "dtlME{Bx
} %/pc=i|+
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/** QBihpA1;
* @param hasPrePage S{:Cu}o
* The hasPrePage to set. 7 :U8 f:
*/ t$I|E
publicvoid setHasPrePage(boolean hasPrePage){ !\x?R6K
this.hasPrePage = hasPrePage; "~\*If
} N RSU+D-z
P
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/** p6[ (81
* @return Returns the totalPage. -;Uj|^
* IU9,
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*/ "+h/-2rA
publicint getTotalPage(){ E9$H nj+m
return totalPage; B*79qq
} |^Kjz{
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/** j^EbO3
* @param totalPage vYnftJK&
* The totalPage to set. V^rW?Do
*/ 8zmv
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publicvoid setTotalPage(int totalPage){ jQ$BPEG&X
this.totalPage = totalPage; zP nC=h|g
} h(N=V|0
$$4W}Ug3U
} fM^<+o@
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yL&/m~{s
] .5OX84
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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个PageUtil,负责对Page对象进行构造: $E.XOpl&I
java代码: SFpQ#
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/*Created on 2005-4-14*/ e{!vNJ0`
package org.flyware.util.page; H(> M
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import org.apache.commons.logging.Log; .@k *p >K
import org.apache.commons.logging.LogFactory; KyLp?!|>
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/** 1JeJxzv>C
* @author Joa tlGWl0V?7Q
* ? OsS`)T
*/ j04/[V)
publicclass PageUtil { \]8i}E1
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privatestaticfinal Log logger = LogFactory.getLog aD|Yo
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(PageUtil.class); 7cw]v"iv
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/** 98UlNP
* Use the origin page to create a new page tIGs>, a=
* @param page M&[b.t*
* @param totalRecords N-%#\rPq.
* @return Pux)>q] C
*/ @T7PZB&xnl
publicstatic Page createPage(Page page, int , N
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totalRecords){ oEIqA
return createPage(page.getEveryPage(), Yi Zx{5
) b:4uK
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page.getCurrentPage(), totalRecords); 5f_7&NxT
} @vAFfYU9<.
b n-=fb(
/** `qu]Pxk
* the basic page utils not including exception CQ> ]jQ,2
4B$bj`h
handler WG%2<Q^
* @param everyPage ,q</@}.\wN
* @param currentPage n7DLJ`ho{
* @param totalRecords 2AK}D%jfc
* @return page #r}uin*jD
*/ =v0~[E4
publicstatic Page createPage(int everyPage, int xb`CdtG2.
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currentPage, int totalRecords){ 5"gL.Ez
everyPage = getEveryPage(everyPage); rzT{-DZB[4
currentPage = getCurrentPage(currentPage); kM`7EPk
int beginIndex = getBeginIndex(everyPage, CQ1 8%w6
Ja [#[BJ?
currentPage); X6kaL3L}
int totalPage = getTotalPage(everyPage, {US>)I
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totalRecords); oHsP?%U
boolean hasNextPage = hasNextPage(currentPage, OjATSmZ@@
o? \Gm
totalPage); :mp$\=
boolean hasPrePage = hasPrePage(currentPage); tJm{I)G
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returnnew Page(hasPrePage, hasNextPage, b1)\Zi
everyPage, totalPage, v,0<9!'v
currentPage, 7d9Z/J@>
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beginIndex); 6[+j'pW?
} PbN3;c3
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privatestaticint getEveryPage(int everyPage){ ^A#x<J+
return everyPage == 0 ? 10 : everyPage; (&c,twa~
} {(0Id !
)_Iz>)
privatestaticint getCurrentPage(int currentPage){ +{*)}[w{x
return currentPage == 0 ? 1 : currentPage; EL +,jrU~
} |^!Vo&T
A]xCF{*)&
privatestaticint getBeginIndex(int everyPage, int 0_HJ.g!
@,Jb7V<
currentPage){ vX.]hp5~
return(currentPage - 1) * everyPage; A^L?_\e6
} e^WqJ7j
5L3{w+V
privatestaticint getTotalPage(int everyPage, int >~wu3q
-(
Kh.h
totalRecords){ KBj@V6Q
int totalPage = 0; y#e ?iE@
AysL-sqR
if(totalRecords % everyPage == 0) R8ZD#,;
totalPage = totalRecords / everyPage; +C5#$5];
else ;-Ado8
totalPage = totalRecords / everyPage + 1 ; zzE]M}s
b"3uD`
return totalPage; k.Gl4
x
} vX 1W@s
Ys%'#f
privatestaticboolean hasPrePage(int currentPage){ t%HI1eO7h
return currentPage == 1 ? false : true; z L8J`W
} X2{`l8%Ek
QA,*:qx
privatestaticboolean hasNextPage(int currentPage, 5\3 swP_7
m{O
Dz:
int totalPage){ MYu`c[$jZ
return currentPage == totalPage || totalPage == f-&ATTx`J
t)!V+Qcb
0 ? false : true; 4znH$M>bU
} C$_G'XI
8=pv/o
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} p9Z].5Pd"
BjB&[5?z
"]<w x_!+}
sX!3_'-
Wt"ww~h`(
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。 z6 a,0&;-L
bl`D+/V
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 i)[kubM
LS{bg.e
做法如下: 0W_mCV
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 X*)?LxTj
'9"%@AFxZ
的信息,和一个结果集List:
}Zt.*%
java代码: R)Q/Ff@o0
l[Tt[n
@wMQC\Z
/*Created on 2005-6-13*/ @Jm.HST#S8
package com.adt.bo; !. p
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import java.util.List; v`
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W oWBs)E
import org.flyware.util.page.Page; FN>L7
*,0
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/** OgQntj:%lN
* @author Joa 9lKRL'QR
*/ }|SIHz!R
publicclass Result { 6-ti Rk~
%uj[ `
private Page page; .(JE-upJ"
hRa\1Jt>a
private List content; *^uGvJXF
:Jm!=U%'Z
/** 3Fgz)*Gu]
* The default constructor '!AT
*/ Etw~*
public Result(){ & \JLTw
super(); r1+c/;TpZ
} 9uKOR7.zbo
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/** @`5QG2
* The constructor using fields KM 5jl9Vv
* y2GQN:X
* @param page (X*'y*:
* @param content R08&cd#$
*/ p?}f|mQS)
public Result(Page page, List content){ '^e0Ud,
this.page = page; hI*`> 9l
this.content = content; |y klT
} re]%f"v:5
h,]tQ#!s8
/** z/)$D
* @return Returns the content. ]F
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*/ 3xP~~j;7
publicList getContent(){ JR])xPI`
return content; ,tau9>!
} ix:2Z-
33*^($bE&
/** XMomFW_@
* @return Returns the page. KuIkul9^%
*/ 3'.!
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public Page getPage(){ HJc<Gwm
return page; fn3*2
} tp7oc_s?.
tsck|;v
/** aXQ&@BZ{j
* @param content AbL5 !'
* The content to set. m\_+)eI|
*/ L7X7Zt8%
public void setContent(List content){ B^H4Q
4-
this.content = content; j'\>Nn+
} !&qx7eOSpP
&Q2NU$
/** yVT&rQ"{
* @param page Um/CR!
* The page to set. 2TE\4j
*/ 8b-7]%
publicvoid setPage(Page page){ K/!/M%GB6
this.page = page; lB=(8.
} 0Wjd-rzc,
} XAw2 X;F%
lQ+Ru8I
"(Mvl1^BT
>s;oOo+5
izXbp02
2. 编写业务逻辑接口,并实现它(UserManager, ${wU+E*
Y,3z-Pa=@
UserManagerImpl) u9esdOv
java代码: `Q:de~+AM{
H~~7~1"x
>/(i3)
/*Created on 2005-7-15*/ AqKHjCI
package com.adt.service;
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Cw6>^
import net.sf.hibernate.HibernateException; n>u.3wL
wYZy e^7
import org.flyware.util.page.Page; W/b"a? wE{
s.f`.o
import com.adt.bo.Result; d&/^34gn
)C'G2RV
/** X7t5b7
* @author Joa TFAYVK~
*/ ~D<7W4c
publicinterface UserManager { E%-Pyg*
3yeK@>C
public Result listUser(Page page)throws R1II k
VI(RT-S6
HibernateException; `2Wl
}9{dR4hD
} hfJrQhmE
b\kN_
h=uiC&B
_cW_u?0X:
GwTT+
java代码: ^`l"'6
{
z-5GH|
Hlz'a1\:O]
/*Created on 2005-7-15*/ pw0Px
package com.adt.service.impl; |Dl*w/n
}@3Ud'
Y
import java.util.List; w%>aR_G
5x:Ift
*
import net.sf.hibernate.HibernateException; ck(CA(_
<f7?PAd
import org.flyware.util.page.Page; <9Lv4`]GU5
import org.flyware.util.page.PageUtil; .}IK}A/-
>+yqjXRzm
import com.adt.bo.Result; F% F
c+?
import com.adt.dao.UserDAO; lt@
import com.adt.exception.ObjectNotFoundException; m-:8jA?
import com.adt.service.UserManager; 5}vRo;-
#JK;&Dg!
/** ;k9
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* @author Joa 3r,1^h
*/ G3 Idxs
publicclass UserManagerImpl implements UserManager { 6a "VCE]
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private UserDAO userDAO; 0!9?H1>
y0/WA4,
/** r]8wOu-'
* @param userDAO The userDAO to set. Q%M'[L?[
*/ + ")qi=
publicvoid setUserDAO(UserDAO userDAO){ {DKXn`V
this.userDAO = userDAO; <C7M";54-
}
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ioE66-n
/* (non-Javadoc) +)/Rql(lY
* @see com.adt.service.UserManager#listUser 08TaFzP81
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(org.flyware.util.page.Page) o0,UXBx
*/ C><<0VhU
public Result listUser(Page page)throws *(?U
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HibernateException, ObjectNotFoundException { @4 zi]v
int totalRecords = userDAO.getUserCount(); I-RdAVB/Ep
if(totalRecords == 0) D6&mf2'u
throw new ObjectNotFoundException $nUd\B$.=
6{JR 0
("userNotExist"); k #1`
page = PageUtil.createPage(page, totalRecords); Jngll
List users = userDAO.getUserByPage(page); D8r>a"gx
returnnew Result(page, users); P<j4\zJ
} &{-oA_@
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} #rn4$
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@<@R=aqE
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ua]\xBWx
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 (SgEt
%JP&ox|^&
询,接下来编写UserDAO的代码: (cOND/S
3. UserDAO 和 UserDAOImpl: `c qH}2s#
java代码: nx!qCgo
e67c:Z
AijPN
/*Created on 2005-7-15*/ "E@NZ*"u
package com.adt.dao; [
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Uv
@!i0W
import java.util.List; )@8'k]Glw.
}<(
"0jC
import org.flyware.util.page.Page; q7 %=`l
b>hBct}
import net.sf.hibernate.HibernateException; i Q]T+}nn_
<Um1h:^
/** fP^W"y
* @author Joa ,wwU`
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*/ f7EIDFX>pt
publicinterface UserDAO extends BaseDAO { &^CL]&/
+z]:CF
publicList getUserByName(String name)throws B$} wF<`k7
8!
|.H p
HibernateException; EmtDrx4!(f
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publicint getUserCount()throws HibernateException; dCf'\@<<
ZYwBw:y}y
publicList getUserByPage(Page page)throws %5Q7 #xU
i#pjv'C
HibernateException; Mr5('9%
WL
IDw@fv
} bm|Jb"T0b
Nt`F0
9S
Z/V`Z* fy
UA69_E{JCH
)#b}qc#`
java代码: mJ6t.%'d
PTuCN
N3XVT{yo
/*Created on 2005-7-15*/ ,mO(!D
package com.adt.dao.impl; L337/8fh
7
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import java.util.List; ~.PPf/
Z8]
!L0E03')k
import org.flyware.util.page.Page; ()JYN5
!^Z[z[
import net.sf.hibernate.HibernateException; 'mBLf&fB
import net.sf.hibernate.Query; O Ey:#9<'
sx)$=~o
import com.adt.dao.UserDAO; KRnB[$3F1
m+72C]9
/** z)
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* @author Joa |!4BWt
*/ s]nGpA[!
public class UserDAOImpl extends BaseDAOHibernateImpl C;58z5*,
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implements UserDAO { K%[}[.cW
1}n)J6m
/* (non-Javadoc) 2HvTM8
* @see com.adt.dao.UserDAO#getUserByName )9A<fwpN
fw(j6:p
(java.lang.String) nU?Xc(Xy
*/ dN$D6*
publicList getUserByName(String name)throws 3&a*]
X*0eN3o.
HibernateException { C)&gL=O*$
String querySentence = "FROM user in class _-|yCo
tK s4}vW
com.adt.po.User WHERE user.name=:name"; ;9!yh\\
Query query = getSession().createQuery |h^G $guw
~L\( /[
(querySentence); Pq{YZMr
query.setParameter("name", name); 26('V `N
return query.list(); ,{`o/F/
} 0btmao-
T0*TTB&b
/* (non-Javadoc) @ 2%.>0s.
* @see com.adt.dao.UserDAO#getUserCount() 6S! lD=
*/ m5'__<
publicint getUserCount()throws HibernateException { , IMT '*
int count = 0; EvH(Po h
String querySentence = "SELECT count(*) FROM 7b7%(
(_%JF[W
user in class com.adt.po.User"; tvj'{W
Query query = getSession().createQuery lk+=26>
Yn[EI7D
(querySentence); iP#A-du
count = ((Integer)query.iterate().next i)`zKbK
*mK);@pL
()).intValue(); *s<dgFA'
return count; Vne.HFXA
} ;8%@Lan
Ivt)Eg
/* (non-Javadoc) ?VOs:sln
* @see com.adt.dao.UserDAO#getUserByPage nI|Lx`*v
HkfSx rTgQ
(org.flyware.util.page.Page) QAOk
*/ R+ #.bQg
publicList getUserByPage(Page page)throws @0/@p"j
-+
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HibernateException { p@N Er,GB
String querySentence = "FROM user in class qN`]*baS
x%:>Ol
com.adt.po.User"; !cFE^VM_;
Query query = getSession().createQuery ,h^;~|GT
<2TB9]2. g
(querySentence);
6>N u=~
query.setFirstResult(page.getBeginIndex()) 93Ci$#<y
.setMaxResults(page.getEveryPage()); qG2\`+v
return query.list(); {6=H/g=:i
} MeK\eZ\
9/X v&<Tn
} fbx;-He!
-fSKJo#}|
i/O,`2
&' Nk2{
$CQwBsYb=
至此,一个完整的分页程序完成。前台的只需要调用 7z P
(PT?h>|St
userManager.listUser(page)即可得到一个Page对象和结果集对象 g6a3MJV`
c J"]yG)=
的综合体,而传入的参数page对象则可以由前台传入,如果用 rfZj8R&
RQK**
webwork,甚至可以直接在配置文件中指定。 whg4o|p
~RR_[t2Z
下面给出一个webwork调用示例: <1'X)n&Kw$
java代码: 5f`XFe$8
cnUU1Uz>
Nh7!Ah
/*Created on 2005-6-17*/ -)vp&-
package com.adt.action.user; n]ppO
U|[
c&I,eds
import java.util.List; 4iPua"8
z_,]fd=o
import org.apache.commons.logging.Log; xz+`]Q
import org.apache.commons.logging.LogFactory; &_%+r5
import org.flyware.util.page.Page; <2@<r
t{
- m x3^
import com.adt.bo.Result; n5,Pq+[
import com.adt.service.UserService; &<