Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 -)X{n?i
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 H-185]7
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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 N3ZiGD
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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 Y:wF5pp;
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分页支持类: e|VJ9|;3
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java代码: 0F^]A"kF
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package com.javaeye.common.util; zwnw'
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import java.util.List; Ss 2$n
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publicclass PaginationSupport { ^PC\E}
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publicfinalstaticint PAGESIZE = 30; P])L8zK
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privateint pageSize = PAGESIZE; wk@yTTnb
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privateList items; 2hy NVG&$
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privateint totalCount; [7RheXO<
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privateint[] indexes = newint[0]; FRgLlp8x
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privateint startIndex = 0; v~}5u
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public PaginationSupport(List items, int 847 R
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totalCount){ ?I\v0H*
setPageSize(PAGESIZE); { UOhVJy
setTotalCount(totalCount); 9k}<F z"^.
setItems(items); l
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setStartIndex(0); HVGr-/
} v
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public PaginationSupport(List items, int 8)Zk24:])_
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totalCount, int startIndex){ xor TL8
setPageSize(PAGESIZE); T/5"}P`
setTotalCount(totalCount); <raG07{!*
setItems(items); y:,9I`aW
setStartIndex(startIndex); 8?1o<8hV
} Mn@$;\:
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public PaginationSupport(List items, int 5>P7]?U.]
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totalCount, int pageSize, int startIndex){ ]n5"Z,K
setPageSize(pageSize); ]^ #`j
setTotalCount(totalCount); d&u7]<yDA
setItems(items); ZBJ3 VK
setStartIndex(startIndex); -w ~(3(
} .'/l'>
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publicList getItems(){ 2e.N"eLNt
return items; 6- ]h5L]
} Gqt-_gga
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publicvoid setItems(List items){ [O_^MA,z
this.items = items; UiIF6-ZZ!
} &6/%kkv
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publicint getPageSize(){ W' ep6O
return pageSize; J$QBI&D
} LN^UC$[tk
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publicvoid setPageSize(int pageSize){ 9 mPIykAj8
this.pageSize = pageSize; 'gDe3@ci!
} !| xZ6KV
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publicint getTotalCount(){ )* TF"
return totalCount; 9U^$.Lb
} QrC/ssf}
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publicvoid setTotalCount(int totalCount){ *b"CPg/\
if(totalCount > 0){ ;'HF'Z
this.totalCount = totalCount; -72j:nk
int count = totalCount / Yj|]Uff8O
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pageSize; Obo _YE
if(totalCount % pageSize > 0) eh<rRx"[
count++; ]*;F. pZ
indexes = newint[count]; Go <'
for(int i = 0; i < count; i++){ ^.vmF>$+I
indexes = pageSize * 6>,#
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} TsHF
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}else{ EgNH8i
this.totalCount = 0; `G?qY8
} q (>c`5
} 7tgFDLA
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publicint[] getIndexes(){ &g0g]G21*I
return indexes; :#$F)]y'\
} J#aVo&.Y
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publicvoid setIndexes(int[] indexes){ XlkGjjW#/J
this.indexes = indexes; ia4k :\
} TvQ^DZbe
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publicint getStartIndex(){ ]1sNmi$T
return startIndex; DZs^ 2Zc
} i8~$o:&HT
c!Dc8=nE0m
publicvoid setStartIndex(int startIndex){ xU}M;4kH~
if(totalCount <= 0) >SDpuG&>
this.startIndex = 0; f^9&WT
elseif(startIndex >= totalCount) 3.vgukkk5
this.startIndex = indexes GaBTj_3
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[indexes.length - 1]; JE!("]&
elseif(startIndex < 0) =_PvrB 2'
this.startIndex = 0; yC
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else{ -$YJfQE6G
this.startIndex = indexes XmWlv{T+
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[startIndex / pageSize]; l67KJ
} i- lKdpv
} T?npQA07=
*)> do
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publicint getNextIndex(){ <I2z&
int nextIndex = getStartIndex() + q*8lnk
{/}^D-
pageSize; B~TN/sd
if(nextIndex >= totalCount) #3MKH8k&~
return getStartIndex(); {TAw)!R~
else ,2`~ NPb
return nextIndex; H}nJbnU
} AhxGj+
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publicint getPreviousIndex(){ #w>~u2W
int previousIndex = getStartIndex() - 7[KCWJ
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pageSize; u7=T(4a
if(previousIndex < 0) YaL]>.;Z:"
return0; $}tjS3klr
else P`"mM?u
return previousIndex; it1/3y
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} {1~T]5
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} WRpyr
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抽象业务类 9%!dNnUk
java代码: V'StvU
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/** fKkjn4&W
* Created on 2005-7-12 9lspo~M
*/ Ty+I8e]{
package com.javaeye.common.business; r:9gf?(&
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import java.io.Serializable; >n$!<
import java.util.List; &mkpJF/
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import org.hibernate.Criteria; W3JF5*
import org.hibernate.HibernateException; .zC*Z&e,.[
import org.hibernate.Session; O4Dr ]Xc]
import org.hibernate.criterion.DetachedCriteria; ~<ri97)
import org.hibernate.criterion.Projections; g}Qx`65:
import 4~|<`vqN
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org.springframework.orm.hibernate3.HibernateCallback; ngyY
import 44-r\>
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org.springframework.orm.hibernate3.support.HibernateDaoS ` |Fp^gM
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upport; "s_Z&
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import com.javaeye.common.util.PaginationSupport; C-SLjJw
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public abstract class AbstractManager extends PC/!9s0W
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HibernateDaoSupport { EUcKN1
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privateboolean cacheQueries = false; 2 ZG@!Y|
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privateString queryCacheRegion; Yx%bn?%;&
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publicvoid setCacheQueries(boolean (?Q|s,
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cacheQueries){ PRr*]$\&Mj
this.cacheQueries = cacheQueries; -s"0/)HD
} !7 _\P7M
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publicvoid setQueryCacheRegion(String /[pqI0sf<A
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queryCacheRegion){ U^_D|$6
this.queryCacheRegion = _gV8aH ZyM
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queryCacheRegion; qrBZvJU
} D}{b;Un
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publicvoid save(finalObject entity){ G{lcYP O
getHibernateTemplate().save(entity); &/WAZs$2n
} _>_j\b
@ 4UxRp6+
publicvoid persist(finalObject entity){ %ROwr[Dj=
getHibernateTemplate().save(entity); [Z<Z;=t
} |NMO__l@
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publicvoid update(finalObject entity){ w^;DG
getHibernateTemplate().update(entity); a5?8QAO~r
} >K)2NLW\xA
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publicvoid delete(finalObject entity){ Iti0qnBN5
getHibernateTemplate().delete(entity); g22gIj]
} o"q+,"QL
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publicObject load(finalClass entity, s3
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finalSerializable id){ 6/Y1 wu
return getHibernateTemplate().load p>kq+mP2bc
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(entity, id); !I8f#'p
} I1=(. *B}
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publicObject get(finalClass entity, k1}hIAk3u
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finalSerializable id){ #R5U
return getHibernateTemplate().get ,=PKd&
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(entity, id); |b.z*G
} PCE4W^ns
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publicList findAll(finalClass entity){ LU2waq}VA
return getHibernateTemplate().find("from p3]Q^KFS
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" + entity.getName()); 5<R%H{3j
} 1W,(\'^R
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publicList findByNamedQuery(finalString :b/J\
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namedQuery){ g8pO
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return getHibernateTemplate ;JTt2qQKo
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().findByNamedQuery(namedQuery); kgW @RD|
} uA~slS
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publicList findByNamedQuery(finalString query, RFfIF]~3
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finalObject parameter){ cxP&^,~
return getHibernateTemplate y8
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().findByNamedQuery(query, parameter); [EZYsOr.
} %&+59vq
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publicList findByNamedQuery(finalString query,
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finalObject[] parameters){ Fo|xzLm9*|
return getHibernateTemplate jna;0)
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().findByNamedQuery(query, parameters); !a-b6Aa
} fZN><3MO>
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publicList find(finalString query){ Z"v<0]rN
return getHibernateTemplate().find a.%LHb
fi%r<]@
(query); u$*>`Xe6
} nzsl@1s
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publicList find(finalString query, finalObject ZxHJ<2oD
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parameter){ gNj7@bX~
return getHibernateTemplate().find SNY (*
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(query, parameter); D$r
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} l54
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public PaginationSupport findPageByCriteria 6NLW(?]
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(final DetachedCriteria detachedCriteria){ \
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return findPageByCriteria >lzA]aM$c
+RDJY(Y$
(detachedCriteria, PaginationSupport.PAGESIZE, 0); :0~QRc-u
} \;9W.d1iU
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public PaginationSupport findPageByCriteria UT]?;o"
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(final DetachedCriteria detachedCriteria, finalint /n{1o\
"&o,yd%
startIndex){ 2xxB\J
return findPageByCriteria ;)hw%Z]Jj$
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(detachedCriteria, PaginationSupport.PAGESIZE, xBM>u,0.F
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startIndex); nWYCh7
} %JL];
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public PaginationSupport findPageByCriteria f@ `*>"
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(final DetachedCriteria detachedCriteria, finalint "VUYh$=[
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pageSize, S\x=&R z
finalint startIndex){ p9[6^rjx8
return(PaginationSupport) >s EjR!
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getHibernateTemplate().execute(new HibernateCallback(){ &1^%Nxu1
publicObject doInHibernate 4YROB912
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(Session session)throws HibernateException { WI[:-cv
Criteria criteria = `N87h"
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detachedCriteria.getExecutableCriteria(session); 5f7zk
int totalCount = ERMa# L
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((Integer) criteria.setProjection(Projections.rowCount 1Y/$,Oa5
\Sy7"a
()).uniqueResult()).intValue(); 0D&> Gyc*0
criteria.setProjection )}lRd#V
^))RM_ic
(null); p<GR SJIk=
List items = v! hY
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criteria.setFirstResult(startIndex).setMaxResults OM83S|1s
_ -..~K.|
(pageSize).list(); LF<wt2?*
PaginationSupport ps = -_A$DM!^=w
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new PaginationSupport(items, totalCount, pageSize, t%VDRZo7
[ AzO:A
startIndex); > 0>
return ps;
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} Fwg^(;bL
}, true); t'qL[r%?
} q0xjA
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public List findAllByCriteria(final x_w~G]! /
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DetachedCriteria detachedCriteria){ +%*&.@z_
return(List) getHibernateTemplate Qs 2.ef?
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().execute(new HibernateCallback(){ |L3X_Me
publicObject doInHibernate |`rJJFA
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(Session session)throws HibernateException { U.0kR/>Z=
Criteria criteria = MN8H;0g-
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detachedCriteria.getExecutableCriteria(session); PR7f(NC
return criteria.list(); >4i>C
} ]/2T\w.<
}, true); @r7:NU}
} l&(l$@t
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public int getCountByCriteria(final ;/O#4]2*
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DetachedCriteria detachedCriteria){ rxZi8w>}
Integer count = (Integer) 7:=k`yS,
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getHibernateTemplate().execute(new HibernateCallback(){
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publicObject doInHibernate K`%tGVY
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(Session session)throws HibernateException { \.{AAj^qD
Criteria criteria = v({N:ya
},-*
detachedCriteria.getExecutableCriteria(session); Tenf:Hm/k
return wEft4o
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criteria.setProjection(Projections.rowCount :*i f
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()).uniqueResult(); fL*T3[d
} <E,%@
}, true); r|<DqTc6l
return count.intValue(); Ww3wsy x
} 2B1xUj ]
} X$?3U!
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用户在web层构造查询条件detachedCriteria,和可选的 .)XP\m\
@I3eK^#|P
startIndex,调用业务bean的相应findByCriteria方法,返回一个 q1VH5'p@
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PaginationSupport的实例ps。 vG.9H_&
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ps.getItems()得到已分页好的结果集 ^_+XDO
ps.getIndexes()得到分页索引的数组 B}?IEpYp
ps.getTotalCount()得到总结果数 NaUr!s
ps.getStartIndex()当前分页索引 <X7\z
ps.getNextIndex()下一页索引 PgM (l3x
ps.getPreviousIndex()上一页索引 1eS_
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 h11.'Eej`
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 X"MU3]
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一下代码重构了。 Qeq5 gN]
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我把原本我的做法也提供出来供大家讨论吧: wE\3$ s/{D
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首先,为了实现分页查询,我封装了一个Page类: 0ZpFE&
java代码: CO+/.^s7}S
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/*Created on 2005-4-14*/ ,,L2(N
package org.flyware.util.page; VR{+f7:}
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/** d(`AXyw
* @author Joa '])2k@o@
* O\KQl0*l\\
*/ vdDludEv
publicclass Page { sJx+8
-
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/** imply if the page has previous page */ ./6<r OW
privateboolean hasPrePage; 0C%W&;r0
eJCjJ)
/** imply if the page has next page */ 6vKS".4C
privateboolean hasNextPage; o]n!(f<(*
g| <wyt[
/** the number of every page */ YGvUwj'2a
privateint everyPage; R<ND=[}s
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/** the total page number */ =WZqQq{
privateint totalPage; w~R`D
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/** the number of current page */ sZgRt
privateint currentPage; "Ml&[Oge
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/** the begin index of the records by the current bizTd
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query */ d%@~mcH>
privateint beginIndex; `?(Bt|<>
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/** The default constructor */ g9fq5E<G
public Page(){ `Hx~UH)
@wmi5oExc
} t>)45<PEw
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/** construct the page by everyPage BKa-
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* @param everyPage &)F*@C-
* */ RkeltE~u
public Page(int everyPage){ b^c9po
this.everyPage = everyPage; smY$-v)@
} YZ$ZcfXDW
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/** The whole constructor */ 0yM[Z':i'{
public Page(boolean hasPrePage, boolean hasNextPage, bAk&~4Y_"
C#;jYBtT7?
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int everyPage, int totalPage, $h[QQ-
int currentPage, int beginIndex){ ppIbjt6r
this.hasPrePage = hasPrePage; S/ywA9~3Q
this.hasNextPage = hasNextPage; aA`/E
this.everyPage = everyPage; i`(^[h
?;
this.totalPage = totalPage; Qe"pW\
this.currentPage = currentPage; FbnO/! $8
this.beginIndex = beginIndex; cXMhq<GkAA
} G.'+-v=\]
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/** 5v\!]?(O;
* @return w9RS)l2FQ
* Returns the beginIndex. 5qUTMT['T
*/ |wE3UWsy
publicint getBeginIndex(){ |H}m 4-+*
return beginIndex; ixm&aW6<
} YT/kC'A
PYRd]%X
/** ^I6^g
* @param beginIndex zjL.Bhiud
* The beginIndex to set. ^&/G|
*/ SHb(O<6
publicvoid setBeginIndex(int beginIndex){ I:V0Xxz5t
this.beginIndex = beginIndex; ]&~]#vB#
} {4aWR><
l%R50aL
/** x_!0.SU
* @return Il@Y|hK
* Returns the currentPage. @.$Xv>Jt$
*/ +y2[msBs
publicint getCurrentPage(){ }{ 9&:!uA
return currentPage; ^04Q %,
} P|2E2=G
j;_c+w!P
/** Q zZ;Ob]'
* @param currentPage pCpb;<JG
* The currentPage to set. 4F>Urh+
*/ IPSF]"}~
publicvoid setCurrentPage(int currentPage){ Wjh/M&,
this.currentPage = currentPage; E@05e
} W>(/ bX
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/** vzel#
* @return Y!q!5Crfi
* Returns the everyPage. -V"22sR]
*/ K
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publicint getEveryPage(){ Uawpfgc}
return everyPage; "N:XzG
} _sE#)@p
@;xMs8@
/** yL^UE=#C_
* @param everyPage ?; YC'bF
* The everyPage to set. @pI5lh
*/ f=!PllxL:
publicvoid setEveryPage(int everyPage){ CxhY$%C (L
this.everyPage = everyPage;
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} Q(d9n8
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/** Fhz*&JC#
* @return l:6,QaT1
* Returns the hasNextPage.
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*/ }u+a<:pkK
publicboolean getHasNextPage(){ 6<,dRn
return hasNextPage; m]_FQWfet
} qQi.?<d2"s
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/** Ko&hj XHx
* @param hasNextPage !}\4utHY
* The hasNextPage to set. 3bqC\i^[\m
*/ m+{K^kr[
publicvoid setHasNextPage(boolean hasNextPage){ =@u 5|:
this.hasNextPage = hasNextPage; dLsn\m>
} xCzebG["
_ 7PMmW@
/** B()/.w?A
* @return fW`&'!
* Returns the hasPrePage. kY,U8a3!
*/ 1C Pjil*eb
publicboolean getHasPrePage(){ Iq+>qX
return hasPrePage; MC0TaP
} #zrTY9m7
e}@)z3Q<l
/** `6y{.$ z
* @param hasPrePage P X;Ed*y
* The hasPrePage to set. ;n=. {[,
*/ ~'5
publicvoid setHasPrePage(boolean hasPrePage){ Uw-p758dD
this.hasPrePage = hasPrePage; hqk}akXt
} LAx4Xp/
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/** 0w'j+
* @return Returns the totalPage. Et"?8\"n7
* T&T/C@z'R
*/ 58%'UwKn
publicint getTotalPage(){ ?6c-7QV
return totalPage; j7FN\
cz
} G5dO 3lwq
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/**
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* @param totalPage H$ftGwS8
* The totalPage to set. ~`>e5OgOJ
*/ /2{5;
publicvoid setTotalPage(int totalPage){ .yT8NTu~0j
this.totalPage = totalPage; mD:IO
} FtufuL?JS
T{]~07N?
} [md u!!*
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2>}xhQJ
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 krq/7|
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个PageUtil,负责对Page对象进行构造: 7z\m;
1
java代码: IdIrI
#jpoHvth
VHOfaCE
/*Created on 2005-4-14*/ xRuFuf8
package org.flyware.util.page; Mh(]3\
H?}[r)|(3i
import org.apache.commons.logging.Log; P+MA*:
import org.apache.commons.logging.LogFactory; p3ISWJa!
`"i Y*
/** at!Y3VywG
* @author Joa l?Y_~Wuw
* d;Hn#2C
*/ syx\gz
publicclass PageUtil { W$JebW<z(
9 7%0;a8
privatestaticfinal Log logger = LogFactory.getLog JB</euyV
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(PageUtil.class); =k}SD96
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/** }}QT HR
* Use the origin page to create a new page G{aT2c
* @param page TUL_TR
* @param totalRecords 0Q"u#V Sp
* @return ]U[X1W+@
*/ JJV0R}z?TV
publicstatic Page createPage(Page page, int o
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bf_I9Z3m
totalRecords){ NRnRMY-
return createPage(page.getEveryPage(), 6{x,*[v
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page.getCurrentPage(), totalRecords); -B#yy]8
} g]*
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/**
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* the basic page utils not including exception ?3z- _8#
;TQf5|R\K
handler tg4Y i|5
* @param everyPage z^o 1GY
* @param currentPage ;vhyhP.oM
* @param totalRecords A6<C-1
N}j
* @return page I4rPHZ|
*/ 8pM>Co!
publicstatic Page createPage(int everyPage, int L+B?~_*
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currentPage, int totalRecords){ pDPxl?S
everyPage = getEveryPage(everyPage); d lH$yub
currentPage = getCurrentPage(currentPage); nM=e]qH
int beginIndex = getBeginIndex(everyPage, Y**|N8e
QH4wUU3X
currentPage); a\kb^D=T
int totalPage = getTotalPage(everyPage, w&Dv8Wv+Oq
?&WYjTU]H
totalRecords); `T/~.`R
boolean hasNextPage = hasNextPage(currentPage, LW#M@
t{!
totalPage); T1B|w"In
boolean hasPrePage = hasPrePage(currentPage); g1(Xg.
JGiKBm;
returnnew Page(hasPrePage, hasNextPage, +ww^ev%
everyPage, totalPage, ||2Q~*:
currentPage, hf!|\f
F}Mhs17!|
beginIndex); G
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} ;S$Ll*f>D
5yh/0i5 |
privatestaticint getEveryPage(int everyPage){ JnD{J`:
return everyPage == 0 ? 10 : everyPage; &a> lWE
} y$Zj?Dd#
>1L=,M
privatestaticint getCurrentPage(int currentPage){ t^=U*~
return currentPage == 0 ? 1 : currentPage; mIZwAKo
} O|kKwadC
JL}\*
privatestaticint getBeginIndex(int everyPage, int u#W5`sl
B UUf;Vv
currentPage){ 0m[dP
return(currentPage - 1) * everyPage; RKd
} ydl jw
1Wg-x0R
privatestaticint getTotalPage(int everyPage, int vY6W|<s
NX* O_/
totalRecords){ ir>]r<Zl
int totalPage = 0; 5FvOznK^e
FHy76^h>e
if(totalRecords % everyPage == 0) pvWau1ArNq
totalPage = totalRecords / everyPage; Hyk'c't_O
else 5G}6;U Y
totalPage = totalRecords / everyPage + 1 ; !.-tW7
]>##`X
return totalPage;
&'|B =7
} h4&;?T S
:2V^K&2L
privatestaticboolean hasPrePage(int currentPage){ -P=g3Q i
return currentPage == 1 ? false : true; p?(L'q"WK
} {B$2"q/~
:@
uIxa$[
privatestaticboolean hasNextPage(int currentPage, <x%M3BTx
P=AS>N^yaL
int totalPage){ $*MCUnl
return currentPage == totalPage || totalPage == Ob +9W
a+41|)pt
0 ? false : true; /%x7+Rl\-^
} !&kL9A).
(Ha@s^?.C
UyYfpL"$A"
} _cJ[
FP1
9~AWn g
,a|@d}U
hp!d/X=J_
iCG`3(xL
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。 =?@Q-(bp
khd5 Cf[
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 _fTwmnA
";3*?/uM
做法如下: `hh9"Ws%
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 XaI;2fMGI
;uI~BV*3
的信息,和一个结果集List: $Ptk|qFe
java代码: W+>wu%[L
BW[5o3
i
,#u\l>&$
/*Created on 2005-6-13*/ i`U:gw
package com.adt.bo; cH`^D?#se
qV1O-^&[f=
import java.util.List; JXQPT
}amU[U,
import org.flyware.util.page.Page; -mNQ;zI1
IY(h~O
/** dT@UK^\
* @author Joa 4z4v\IpB
*/ o.:p_(|hI
publicclass Result { ~GB=Nz
85U.wpG
private Page page; _"f :`
3*S[eqMJc
private List content; Ng<1Sd|MV
~&G4)AM
/** $`Nd?\$
* The default constructor '8`T|2
*/ S0w> hr
public Result(){ M8W# io
super(); j\)H
} W*T{,M@Y
-/{af
/** <HoAj"xf
* The constructor using fields q|#MB7e/
* ?qHF}k|
* @param page eMMx8E)B
* @param content pu;3nUH
*/ 9/TY\?U
public Result(Page page, List content){ <bmLy_":
this.page = page; hq_~^/v\
this.content = content; )@7DsV/M
} ija:H'j
s${_K* g6
/** =G>(~+EA
* @return Returns the content. &~~s6
*/ 4 rB8Nm1
publicList getContent(){ ]
pPz@@xx
return content; Agy
<j
} )^; DGzG
L@)&vn]
/** <)#kq1b?
* @return Returns the page. x'`"iZO.t
*/ 4,1oU|fz
public Page getPage(){ 1M5 -pZ[D
return page; Y(i?M~3\t
} r'aY2n^O
UVX"fZ)
/**
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* @param content 3B9nP._
* The content to set. YB!!/ SX4
*/ (!zM\sF
public void setContent(List content){ 3]}'TA`v
this.content = content; (aKZ5>>cN
} `F1dyf!p<
oh\,OW
/** w=J4zkWk
* @param page T%I&txl
* The page to set. RsSXhPk?
*/ W"sr$K2m|
publicvoid setPage(Page page){ b~Z=:'m8
this.page = page; d79N-O-
} s44iEh=V(I
} ,b'4CF
aWvd`qA9r
f'{>AKi=C
'h*Zc}Q:
TlPVHJyt
2. 编写业务逻辑接口,并实现它(UserManager, m^tNqJs8
:,F=w0O
UserManagerImpl) )SiY(8y
java代码: J+2R&3;_O
UC!5
wVY
|~$7X
/*Created on 2005-7-15*/ z+"0>ZN&
package com.adt.service; b=LF%P
Nlt4)
import net.sf.hibernate.HibernateException; YFx=b!/s
:XS"#^aJ
import org.flyware.util.page.Page; Dd/}Ya(Gi
h~ha
import com.adt.bo.Result; rSyaZ6#
0j@Ix EPs
/** 9~Xg#{
* @author Joa Z{}+)Q*Q
*/ dF,DiRD
publicinterface UserManager { i$O#%12l
XiG88Kwv
public Result listUser(Page page)throws &%e"9v2`
)BLmoJOf
HibernateException; U42\.V0
1g i}H)
} q<XcOc5
7Po/_%
s/S+ ec3
L?f qcW{
;D&wh
java代码: M[,^KJ!
6Bdyf(t
FOp_[rR
/*Created on 2005-7-15*/ d| \#?W&
package com.adt.service.impl; cdsQ3o
&7F&}7*c
import java.util.List; \X opU"
z(UX't (q
import net.sf.hibernate.HibernateException; n4*'B*
n\~yX<;X3
import org.flyware.util.page.Page; m|dF30~A
import org.flyware.util.page.PageUtil;
rk|a'&
CjZ6NAHc
import com.adt.bo.Result; '#f?#(
import com.adt.dao.UserDAO; >@Khm"/T
import com.adt.exception.ObjectNotFoundException; JS2!)aqc
import com.adt.service.UserManager; {G.{ad
YHh u^}|jQ
/** y Hw!#gWM
* @author Joa bV7QVu8
*/ rxkBg0Z`a
publicclass UserManagerImpl implements UserManager { [NR1d-Wg
}2xb&6g~o
private UserDAO userDAO; o}R|tOe
:eLLDp<
/** 2o}8W7y
* @param userDAO The userDAO to set. }q x(z^
*/ D4\(:kF\Hg
publicvoid setUserDAO(UserDAO userDAO){ ]Hj`2\KD.d
this.userDAO = userDAO; nK:`e9ES
} |ZuDX87
\]GGVI;u
/* (non-Javadoc) "b;k.Fx
* @see com.adt.service.UserManager#listUser Q2R>lzB
2 ^ kn5
(org.flyware.util.page.Page) s.ey!ew
*/ ^ N_`^m
public Result listUser(Page page)throws [r~~=b7*[
RA~_]Hk
HibernateException, ObjectNotFoundException { F~P/*FFK
int totalRecords = userDAO.getUserCount(); c$.T<r)Z
if(totalRecords == 0) P#9-bYNU
throw new ObjectNotFoundException &`5 :GLV
lc-*8eS
("userNotExist"); +{bh
page = PageUtil.createPage(page, totalRecords); gU*I;s>
List users = userDAO.getUserByPage(page); [ 1D)$"
returnnew Result(page, users); A'(k
Yc
} vev8l\
,XP@ pi
} !j'guT&9]
m"1
?
p!V)55J*
L/%xbm~
;WPI+`-
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 1 pYsjo~
th;]Vo
询,接下来编写UserDAO的代码: *xho
3. UserDAO 和 UserDAOImpl: 0MhxFoFO
java代码: J2x$uO{Bn
akY6D]M
-hm9sNox
/*Created on 2005-7-15*/ t"FRLC
package com.adt.dao; _c,&\ wl$
UvoG<;
import java.util.List; 0$(jBnE
r]Z.`}Kkm
import org.flyware.util.page.Page; T&e%/
DwQp$l'NfW
import net.sf.hibernate.HibernateException; HJ(=?TU
1W4H-/Re
/** %0go%_
* @author Joa P}b Dn;
*/ \>_eEZ5
publicinterface UserDAO extends BaseDAO { <kk'v'GW@
72%
{Wh/
publicList getUserByName(String name)throws ~c'\IM
+ >Fv*lux
HibernateException; j=p|'`
D DZTqsws
publicint getUserCount()throws HibernateException; f2 VpeJ<p
FxMMxY,*%
publicList getUserByPage(Page page)throws S:DcfR=a
+ 4++Z
HibernateException; O{O9}]6
7Co3P@@
} 6YB-}>?
J#_\+G i
&7JEb]1C
">rsA&hN-
"1E?3PFJ
java代码: 3" 8t)s
F5Cqv0HV
%YsRm%q
/*Created on 2005-7-15*/ GWVEIZ
package com.adt.dao.impl; qsQ]M^@>
F\I5fNs@
import java.util.List; $XtV8
|2tSUOZ
import org.flyware.util.page.Page; kvY}
yw7
:ga 9Db9P
import net.sf.hibernate.HibernateException; ;g!xQvcR
import net.sf.hibernate.Query; 8Fyc#Xo8
|v,}%UN2
import com.adt.dao.UserDAO; $v2S;UB v*
99=[>Ck)G
/** \Or]5ogT'
* @author Joa 6uv'r;U]
*/ })Ix.!p
public class UserDAOImpl extends BaseDAOHibernateImpl C8O7i[uc
"@F*$JGT y
implements UserDAO { OD>u$tI9
KI^ q 5D ?
/* (non-Javadoc) @*AYm-k
* @see com.adt.dao.UserDAO#getUserByName B`t)rBy
R
A-^!4tX
(java.lang.String) ~M|NzK_9
*/ `K@5_db\
publicList getUserByName(String name)throws >c~9wv
-sruxF
HibernateException { _S[Rvb1e
String querySentence = "FROM user in class x`b~ZSNJ%
`Nxo0Q
com.adt.po.User WHERE user.name=:name"; 6T5A31 Q
Query query = getSession().createQuery %`8KG(F^
AiR%MD
(querySentence); c=uBT K*
query.setParameter("name", name); Zi15wE
return query.list(); u k>q\j
} KR+ aY.
4C2>0O<^s
/* (non-Javadoc) @Wlwt+;fT
* @see com.adt.dao.UserDAO#getUserCount() }Etd#">
*/ aH~x7N6!
publicint getUserCount()throws HibernateException { Z &ua,:5
int count = 0; 0D W'(#`
String querySentence = "SELECT count(*) FROM e%5'(V-y,
\ZmFH8=|f
user in class com.adt.po.User"; ^Hy)<P
Query query = getSession().createQuery ?kG#qt]Q5
&z1|
(querySentence); 3:z4M9f
count = ((Integer)query.iterate().next U[H+87zg
~50y-
()).intValue(); BdRE*9.0
return count; _AsHw
} o>QFdx
DT1i2!
/* (non-Javadoc) Gff[c%I
* @see com.adt.dao.UserDAO#getUserByPage hA&j?{
Oa3=+_C~$1
(org.flyware.util.page.Page) I*`=[nR
*/ a`GN@
8
publicList getUserByPage(Page page)throws E:LQ!
Z n"TG/:
HibernateException { vi()1LS/!
String querySentence = "FROM user in class >V ]*mS%K
}(O D<
com.adt.po.User"; 3HDnOl8t
Query query = getSession().createQuery ._F6- pl
ft.}$8vIT
(querySentence); Y ~\`0?ST
query.setFirstResult(page.getBeginIndex()) VAG+y/q
.setMaxResults(page.getEveryPage()); zN8&M<mTl
return query.list(); ^`B##9g~
} E?;T:7.%
_sCJ3ZJ
} ^~*[~
+p%5/smfs
#xJGuYdv
g}s-v?+
IJb1)
ZuR
至此,一个完整的分页程序完成。前台的只需要调用 CzDR% v x
V+@%(x@D_
userManager.listUser(page)即可得到一个Page对象和结果集对象 6=`m
Bb2r95h}^
的综合体,而传入的参数page对象则可以由前台传入,如果用 aZ`_W|
olQ8s*
webwork,甚至可以直接在配置文件中指定。 JCU3\39}
4q2=:"z4
下面给出一个webwork调用示例: M}KM]<
java代码: ")[Q4H;V
8bKWIN g_n
;JD3tM<
/*Created on 2005-6-17*/ Gh>fp
package com.adt.action.user; r&l*.C*
`__?7"p
)\
import java.util.List; ,VcDvZ7
BD-c 0-+m
import org.apache.commons.logging.Log; ,oi`BOh
import org.apache.commons.logging.LogFactory; 2
vJ[vsrFv
import org.flyware.util.page.Page; 0qV*d
fG[3%e
import com.adt.bo.Result; ?}lp o; $
import com.adt.service.UserService; O%q;,w{prW
import com.opensymphony.xwork.Action; J#OE}xASoA
Ns(L1'9=
/** Vlxb<$5Nh
* @author Joa ,mBKya)
*/ h/+I-],RF
publicclass ListUser implementsAction{ _XO)`D~
Cx3m\
\c
privatestaticfinal Log logger = LogFactory.getLog {J6sM$aj
^TCJh^4na
(ListUser.class); K1wN9D{t'
;
K
6Fe)
private UserService userService; $rQFM[
D A)0Y_
private Page page; bCx1g/
cTIwA:)D
privateList users; UC
LjR<}
36A.h,~
/* oTV8rG
* (non-Javadoc) SAxa7B/U2
* mEc;-b
f
* @see com.opensymphony.xwork.Action#execute() g KmRjK
*/ Wj{Rp{}3
publicString execute()throwsException{ :R*^Izs=
Result result = userService.listUser(page); UE$[;Zg
page = result.getPage(); ?e|:6a+[f
users = result.getContent(); '?>O
return SUCCESS; LU IT=+
} R&|)y:bg|
Y"
+1,?yH
/** AqKx3p6
* @return Returns the page. dK(%u9v
*/ j{w,<Wt>
public Page getPage(){ eYX_V6c
return page; ~m09yc d<
} V1b_z
yLIj4bf
/** '<W,-i
* @return Returns the users. 'UG}E@G
*/ ]!J3?G
publicList getUsers(){ {$TB#=G
return users; WyJfF=<
} A=[f>8
96E7hp !:
/** ht)*Ync
* @param page IEr`6|X
* The page to set. BNoCE!
*/ W]Y!ZfGnN
publicvoid setPage(Page page){ LW
3J$Am
this.page = page; }(%}"%$
} `L[32B9
p1gX4t]%}a
/** k@)m- K
* @param users }b\q<sNE{
* The users to set. IS*"_o<AR
*/ JOne&{h]J"
publicvoid setUsers(List users){ hA1hE?c`
this.users = users; vc{]c
}
} w,#W&>+&
l'lDzB+.*
/** #_L&
* @param userService #cF8)GC
* The userService to set. .lj! ~_
*/ G]DN!7]@g
publicvoid setUserService(UserService userService){ *>*/|
this.userService = userService; ?,e:c XhE2
}
>Pd23TsN
} JP*wi-8D
Y'H/
$M N
xdU
pp~}+.
_$_CR\$
Tq; "_s
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, v%~ViOgL\
|nZB/YZt
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 5*za]
MC)W?
么只需要: J0mCWtx&
java代码: dQ~"b=
]Tw6Fg1o>
ZO6bG$y64
<?xml version="1.0"?> @z JZoJL]J
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork #_sVB~sn@
"EkO>M/fr
1.0//EN" "http://www.opensymphony.com/xwork/xwork- > 5:e1a?9
ssbyvzQ
1.0.dtd"> aNU%OeQA
6}lEeMRW
<xwork> Q>g$)-8
F(fr,m3
<package name="user" extends="webwork- H0NyxG<
dY`J,s
interceptors"> Ijro;rsEKM
(lsod#wEMg
<!-- The default interceptor stack name E1w XG
kV9NFo22
--> /j\TmcnU^
<default-interceptor-ref v86`\K*0Y
{#Cm> @')
name="myDefaultWebStack"/> c0p=/*s(
SFNd,(kB*z
<action name="listUser" DOU?e9I2
%--5bwZi
class="com.adt.action.user.ListUser"> 4\WkXwoqQO
<param buyz>ICP
b:I5poI3
name="page.everyPage">10</param> -7VV5W
<result 1c~#]6[
e1 }0f8%
name="success">/user/user_list.jsp</result>
o*1`, n
</action> I _G;;GF
~mo`
</package> _JO @O^Ndd
> o`RPWs
</xwork> @CUDD{1o
<"% h1{V
v!C+W$,T
S|w] Q
tV4aUve
6RodnQ
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 ~ZN9 E-uL
D+PUi!
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 Jl,x~d
XKIJ6M~5k
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 ub&29Qte
>G7U7R}R
S6Pb V}
..mz!:Zs0
BEx^IQ2
我写的一个用于分页的类,用了泛型了,hoho - & r{%7
9DE)5/c`v
java代码: @6`@.iZ
Bn:sN_N
pz =Wq4l
package com.intokr.util; xWV7#Z7
?C\9lLX
import java.util.List; Nuq/_x
niBpbsO
/** L]")TQ
* 用于分页的类<br> 4`]1W,t
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 1_]l|`Po
* e|y~q0Q$
* @version 0.01 w Vmy`OV/
* @author cheng #JM*QVzv
*/ .JjuY'-Q
public class Paginator<E> { ^[akB|#\9
privateint count = 0; // 总记录数 NebZGD2K
privateint p = 1; // 页编号 (Cd`~*5
privateint num = 20; // 每页的记录数 H>9$L~
privateList<E> results = null; // 结果 =Ybu_>
\C|06Bs$
/** e0 EJ[bG
* 结果总数 F4Z0g*^x
*/ IQ8AsV&'C
publicint getCount(){ /9Xf[<
return count; !I&Sy]G
} YgDasKFm'
nfB9M1Svn
publicvoid setCount(int count){ hiuPvi}
this.count = count; R 5zV=N
} 1tc9STYR}
U5=J;[w}N
/** Ccmbdw,Z5
* 本结果所在的页码,从1开始 [*v\X %+
* x #g,l2_!
* @return Returns the pageNo. >O=V1
*/ 2[eY q1f!
publicint getP(){ :{2$X|f
3
return p; x]T;W&s
} u{ /gjv
yD"sYT
/** Mk;j"ZDF
* if(p<=0) p=1 0}N^l=jQ
* Fsh-a7Qp
* @param p >sq9c/}X
*/ ;k]pq 4E
publicvoid setP(int p){ ?9A[;j|a0
if(p <= 0) y5}|Y{5
p = 1; HDOa N
this.p = p; In2D32"F
} ,zaveQ~l
k=[Ro
/** 2rM i~8T
* 每页记录数量 k@'.d)y0`
*/ MiRB*eA
publicint getNum(){ :QNEA3Q
return num; &$[{L)D
} P@#6.Bb#V
&\r%&IX/
/** $? Rod;
* if(num<1) num=1 \ZB;K~BV&
*/ ?~Des"F6)1
publicvoid setNum(int num){ -_(!
if(num < 1) zO,sq%vQn'
num = 1; `Ii>wb
this.num = num; .wywO|
} >xN^#$ng}
gUcE,L
/** CgWj9 [
* 获得总页数 >KJ]\`2>)c
*/ gMbvHlT
publicint getPageNum(){ Z[VKB3Pb8
return(count - 1) / num + 1; g@L4G?hLn
} (Lp-3Xx
K^ lVng
/** Ge x^\gf
* 获得本页的开始编号,为 (p-1)*num+1 %oo&M;
*/ =zKp(_[D
publicint getStart(){ kMA>)\
return(p - 1) * num + 1; U
Lq%,ca
} RfD$@q9
Y~6pJNR
/** JcP'+@X"
* @return Returns the results. Jz6PqU|=
*/ `}bUf epMJ
publicList<E> getResults(){ ?l/rg6mbI'
return results; x?kZD~|{)
} T>?~eYHXs
KME
#5=~
public void setResults(List<E> results){ ;S7xJ'H
this.results = results; ntT|G0E
} Q.Acmht#
E9i WGSE
public String toString(){ x9=lN^/4
StringBuilder buff = new StringBuilder -:QyWw/d
*QVE>{
(); ,rKN/{M!
buff.append("{"); lc#H%Qlg
buff.append("count:").append(count); DuWP)#kg
buff.append(",p:").append(p); ~gf$ L9
buff.append(",nump:").append(num); LLE~V~j
buff.append(",results:").append e0TnA
N
2a^(8A`7W
(results); VXa]L4jJ9
buff.append("}"); SCo9[EJ
return buff.toString(); eIO}/npT]Q
} \?o%<c5{
gDv]n^&