Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 S[QrS7
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 9>$p
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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 2+O'9F_v
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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 Q=:|R3U/
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分页支持类: C.QO#b
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java代码: 'm9` 12H
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package com.javaeye.common.util; P>6{&(
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import java.util.List; 2BobH_H
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publicclass PaginationSupport { ZG@q`<:j
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publicfinalstaticint PAGESIZE = 30; LIdF 0
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privateint pageSize = PAGESIZE; h.fq,em+H
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privateList items; !VK|u8i
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privateint totalCount; }&3~|kP~O
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privateint[] indexes = newint[0]; E!AE4B1bd
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privateint startIndex = 0; 8i,K~Bu=
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public PaginationSupport(List items, int xwty<?dRW1
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totalCount){ Xry47a
)
setPageSize(PAGESIZE); %07SFu#
setTotalCount(totalCount); l@:0e]8|o
setItems(items); V1JIht>Opo
setStartIndex(0); #89!'W
} =rK+eG#,
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public PaginationSupport(List items, int 8.~kK<)!
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totalCount, int startIndex){ D
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setPageSize(PAGESIZE); D,ln)["xm
setTotalCount(totalCount); lNBL4yM
setItems(items); o?
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setStartIndex(startIndex); fxIf|9Qi`
} {zFMmPid
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public PaginationSupport(List items, int i 3SHg\~Z
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totalCount, int pageSize, int startIndex){ m#F`] {
setPageSize(pageSize); 9)=ctoZ'
setTotalCount(totalCount); qjc4.,/
setItems(items); RX5dO%
setStartIndex(startIndex); CWS4lx
} b_):MQ1{
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publicList getItems(){ YgoBHE0#
return items; FsryEHz
} x$%!U[!3
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publicvoid setItems(List items){ as_PoCoss
this.items = items; u~-8d;+?y
} +2j AC r
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publicint getPageSize(){ I!?}jo3
return pageSize; ?F;8Pa/
} GM<-&s!Uj
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publicvoid setPageSize(int pageSize){ 6MkP |vr6
this.pageSize = pageSize; ;w[0t}dPl
} OydwE
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publicint getTotalCount(){ l/awS!Q/nF
return totalCount; O8.5}>gDn.
} "w.3Q96r
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publicvoid setTotalCount(int totalCount){ 3%ZOKb"D*
if(totalCount > 0){ *=c1do%F
this.totalCount = totalCount; ;d9QAN&0}
int count = totalCount / '08=yqy4N
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pageSize; #N cK
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if(totalCount % pageSize > 0) uRr o?m<
count++; z]9MM
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indexes = newint[count]; |H+Wed|
for(int i = 0; i < count; i++){ k)Qtfj}uij
indexes = pageSize * 9*?oYm;dX
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i; ]P?vdgEM&
} C 6AUNRpl
}else{ Z/;aT -N
this.totalCount = 0; I(0~n,=j
} iW /}#
} ox (%5c)b|
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publicint[] getIndexes(){ {jX2}
return indexes; NTI+
} }~e%J(
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publicvoid setIndexes(int[] indexes){ 1 Ya`| ?FS
this.indexes = indexes; A$:U'ZG_
} qm o9G
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publicint getStartIndex(){ #?9;uy<j.q
return startIndex; *ppffz
} \)?HJ
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publicvoid setStartIndex(int startIndex){ %F4%H|G
if(totalCount <= 0) `lt"[K<
this.startIndex = 0; =>af@C.2
elseif(startIndex >= totalCount) A=wh@"2
this.startIndex = indexes v OpKNp
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[indexes.length - 1]; <<R*2b
elseif(startIndex < 0) b`O'1r\Y;
this.startIndex = 0; DZPPJ2 }
else{ nK%LRcAs
this.startIndex = indexes R[x_j
[ ~&/s:Vvo
[startIndex / pageSize]; ah+iZ}E%
} wx0j(:B]
} X*@dj_,
_t #k,;
publicint getNextIndex(){ <3C*Z"aQ>|
int nextIndex = getStartIndex() + -I,$_
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pageSize; 'u |c
if(nextIndex >= totalCount) tHwMX1 IG
return getStartIndex(); @wNG{Stj
else 6MMOf\
return nextIndex; OA"q[s
} l&Q`wR5e
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publicint getPreviousIndex(){ W+ko q*P
int previousIndex = getStartIndex() - oEKvl3Hz_
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pageSize; l#Y,R 0
if(previousIndex < 0) XLOh7(
return0; aH/
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else FSW_<%
return previousIndex; X!dYdWw*m
} ;P%1j| 7
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} O5nD+qTQ#
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抽象业务类 G^4hd i3@
java代码: .Od!0(0
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/** MJ
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* Created on 2005-7-12 LR.<&m%~.
*/ A1>OY^p3%
package com.javaeye.common.business; 0Y{yKL
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import java.io.Serializable; ;LSANr&
import java.util.List; (b-MMr
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import org.hibernate.Criteria; *Y7u'v
import org.hibernate.HibernateException; W_(j3pV?Ml
import org.hibernate.Session; EGU
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import org.hibernate.criterion.DetachedCriteria; !1H# 6
import org.hibernate.criterion.Projections; 9BBmw(M}
import 0e ~JMUb
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org.springframework.orm.hibernate3.HibernateCallback; 3/e.38m|
import EPM-df!=
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org.springframework.orm.hibernate3.support.HibernateDaoS 9FYUo
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upport; 4`]^@"{
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import com.javaeye.common.util.PaginationSupport; VfC <WVYiZ
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public abstract class AbstractManager extends
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HibernateDaoSupport { s.N/2F&*W
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privateboolean cacheQueries = false; sF?TmBQ*
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privateString queryCacheRegion; BmMGx8P
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publicvoid setCacheQueries(boolean BBRR)
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cacheQueries){ >#~& -3
this.cacheQueries = cacheQueries; dIa+K?INX
} OXSmt
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publicvoid setQueryCacheRegion(String ~f1%8z
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queryCacheRegion){ NAQAU
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this.queryCacheRegion = *,8^@(th
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queryCacheRegion; >G*eNn
} kmsb hYM)
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publicvoid save(finalObject entity){ }{qZ[/JwqN
getHibernateTemplate().save(entity); wh\}d4gN
} +]A:M6P:{v
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publicvoid persist(finalObject entity){ EQyC1j
getHibernateTemplate().save(entity); '4Ixqb+
} p7VTa~\zA
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publicvoid update(finalObject entity){ }Jve cRtg1
getHibernateTemplate().update(entity); W*4-.*U8a
} ox>^>wR*
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publicvoid delete(finalObject entity){ ^aMg/.j
getHibernateTemplate().delete(entity); 5uNJx5g
} 4 \K7xM!
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publicObject load(finalClass entity, *1
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finalSerializable id){ >CgTs
return getHibernateTemplate().load 1i"WDu*h3
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(entity, id); w%VU/6~
} _ Yx]_Y9I
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publicObject get(finalClass entity, `* ["UER
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finalSerializable id){ \H~T>j{N
return getHibernateTemplate().get axRV:w;E<
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(entity, id); MS>Ge0P("~
} P[#e/qnXu|
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publicList findAll(finalClass entity){ V>%rv'G8
return getHibernateTemplate().find("from V _/%b)*
e*(!^Q1
" + entity.getName()); WZejp}x
} gJXq^~-hd
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publicList findByNamedQuery(finalString SSg8}m5)Q
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namedQuery){ E7 Ul;d
return getHibernateTemplate JEwa
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().findByNamedQuery(namedQuery); OU(8V^.
} GR.^glG?6
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publicList findByNamedQuery(finalString query, }b"yU#`Q\
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finalObject parameter){ +I:Unp
return getHibernateTemplate ;Ax
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().findByNamedQuery(query, parameter); R'`qKc
} Oo8VeRZ
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publicList findByNamedQuery(finalString query, +z\^t_"f
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finalObject[] parameters){ ]z;I_-
return getHibernateTemplate Yty/3T3)e
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H
().findByNamedQuery(query, parameters); mh{d8<Q2
} $Sx'sA2
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publicList find(finalString query){ \fr~
return getHibernateTemplate().find IH&|Tcf\
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(query); +wU@ynw
} S_4?K)n #
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publicList find(finalString query, finalObject ~'H]jN
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parameter){ 8f4b&ah
return getHibernateTemplate().find 4Zddw0|2
m@F`!qY~Y\
(query, parameter); Q&ptc>{bH6
} x8\?}UnB
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public PaginationSupport findPageByCriteria fLD,5SN
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(final DetachedCriteria detachedCriteria){ c(E{6g?
return findPageByCriteria e/&{v8Hmb
]BZA:dd.G
(detachedCriteria, PaginationSupport.PAGESIZE, 0); q[ZT Hd.-
} =tn)}Y.<e
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public PaginationSupport findPageByCriteria vY}g<*
c?*=|}N
(final DetachedCriteria detachedCriteria, finalint k[YS8g-Q
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startIndex){ *3FKt&v 0
return findPageByCriteria 2'\H\|
M,,bf[p$
(detachedCriteria, PaginationSupport.PAGESIZE, SrJGTuXg
beGa#JH,
startIndex); o#gWbAG;]b
} |\t-g"~sN
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public PaginationSupport findPageByCriteria b<ZIWfs
9(7-{,c
(final DetachedCriteria detachedCriteria, finalint _p/UsJ
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pageSize, a:`E0}C
finalint startIndex){ 8z`G,qh
return(PaginationSupport) 4G0m\[Du
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getHibernateTemplate().execute(new HibernateCallback(){ |O+H[;TB6
publicObject doInHibernate )
7@ `ut
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(Session session)throws HibernateException { gp?uHKsM
Criteria criteria = o4,6.1}
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detachedCriteria.getExecutableCriteria(session); /NFj(+&g+
int totalCount = 70nqD>M4
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((Integer) criteria.setProjection(Projections.rowCount 2(+2+}
q`a'gJx#y
()).uniqueResult()).intValue(); 1#2 I
criteria.setProjection MUc$j&
@ioJ]$o7
(null); [ 5b--O
List items = a0E)2vt4
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criteria.setFirstResult(startIndex).setMaxResults ]^7@}Ce_
h"Q8b}$^)
(pageSize).list(); wv1iSfW
PaginationSupport ps = !hy-L_wL]
q!7ANib6O
new PaginationSupport(items, totalCount, pageSize, ]|ag
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startIndex); <2x^slx)?
return ps; i$#;Kpb`^
} O+]ZyHnB
}, true); AKfDXy
} ((;!<5-`s
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public List findAllByCriteria(final @n /nH?L
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DetachedCriteria detachedCriteria){ -3*]G^y2
return(List) getHibernateTemplate mdg8,n
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().execute(new HibernateCallback(){ rJ4S%6w
publicObject doInHibernate FVbb2Y?R
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(Session session)throws HibernateException { /-'}q=M
Criteria criteria = %)1?TU
;[YG@-"XZ
detachedCriteria.getExecutableCriteria(session); fU}ub2_in
return criteria.list(); "+nRGEs6
} @*XV`_!h
}, true); 4e7-0}0
} MJO-q $)c
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public int getCountByCriteria(final -d/
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DetachedCriteria detachedCriteria){ yx[/|nZDC4
Integer count = (Integer) '<)n8{3Q5w
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getHibernateTemplate().execute(new HibernateCallback(){ 8kIksy
publicObject doInHibernate U< fGGCw
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(Session session)throws HibernateException { Of#u
Criteria criteria = ~,Ix0h+H+M
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detachedCriteria.getExecutableCriteria(session); K@]4g49A/j
return eM6<%?b
Dml;#'IF3
criteria.setProjection(Projections.rowCount v ;{#Q&(
_;y9$"A
()).uniqueResult(); Gb6 'n$g
} d7y[0<xM
}, true); u&vf+6=9Dd
return count.intValue(); Hvi49c]]
} 2l'6.
}
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用户在web层构造查询条件detachedCriteria,和可选的 >]TWXmx/w
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 C{rcs'
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PaginationSupport的实例ps。 2F.;;Ab
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ps.getItems()得到已分页好的结果集 9cF[seE"0
ps.getIndexes()得到分页索引的数组 ]%H`_8<gc
ps.getTotalCount()得到总结果数 q54]1TQ
ps.getStartIndex()当前分页索引 tDcT%D {:
ps.getNextIndex()下一页索引 q<|AZ2Ai
ps.getPreviousIndex()上一页索引 tcI*a>
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 6nvz8f3*r]
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 wn%A4-%{
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一下代码重构了。 "KpGlY?^
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我把原本我的做法也提供出来供大家讨论吧: ^yp{32
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首先,为了实现分页查询,我封装了一个Page类: r,p%U!S<hV
java代码: lL3U8}vn
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/*Created on 2005-4-14*/ d$!RZHo10V
package org.flyware.util.page; {EQOP]
g) jYFfGfH
/** chX"O0?"
* @author Joa W|mo5qrLS2
* 0GeTSFj
*/ 7{*>agQh
publicclass Page { #*Ctwl,T
k9!{IScq
/** imply if the page has previous page */ F JyT+
privateboolean hasPrePage; q_58;Bv
(!WD1w
/** imply if the page has next page */ xb8!B
privateboolean hasNextPage; `|q(h Ow2
~]2K^bh8&
/** the number of every page */ + ePS14G
privateint everyPage; kxv1Hn"`{E
YaqJ,"GlT
/** the total page number */ 7kEn \
privateint totalPage; \4fQMG
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/** the number of current page */ a:w#s}bL
privateint currentPage; &^jXEz;
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/** the begin index of the records by the current Km$\:Xo
9%9#_?RW
query */ bk[!8-b/a
privateint beginIndex; NzvXN1_%
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/** The default constructor */ (sZ"iGn%
public Page(){ 6'f;-2
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} mC#>33{
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/** construct the page by everyPage y:uE3Apm
* @param everyPage M_DwUS1?
* */ +NUG
public Page(int everyPage){ X&H"51
this.everyPage = everyPage; 5{,<j\#L
} W"{N Bi
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/** The whole constructor */ Z%UP6%
public Page(boolean hasPrePage, boolean hasNextPage, 'I;zJ`Trd
$XH^~i;
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int everyPage, int totalPage, Q~9^{sHZjP
int currentPage, int beginIndex){ `R^g U]Z,
this.hasPrePage = hasPrePage; @6-jgw>W2
this.hasNextPage = hasNextPage; VIf.q)_k
this.everyPage = everyPage; iy.\=Cs$N
this.totalPage = totalPage; &rR2,3r=
this.currentPage = currentPage; N;%6:I./
this.beginIndex = beginIndex; F#E3q|Q"BS
} v3>UV8c'
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/** y@yD5$/
* @return 8&dF
* Returns the beginIndex. \9EjClfo
*/ HZZn'u
publicint getBeginIndex(){ w0unS`\4
return beginIndex; r3?o9D>
} YS_;OFsd
dPRra{
/** Wd
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* @param beginIndex *LY8D<:zs
* The beginIndex to set. U6s[`H3I{
*/ f|(M.U-
publicvoid setBeginIndex(int beginIndex){ xT2PyI_:
this.beginIndex = beginIndex; 9>#6*/Oa7
} K*d Cc}:`
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/** G3v5KmT
* @return %;!.n{X
* Returns the currentPage. |y!A&d=xYn
*/ ^LLzZnkcZ
publicint getCurrentPage(){ k9F=8q
return currentPage; Eh4=ZEX
} ?aMOZn?
<gBA1oRz
/** <OPArht
* @param currentPage L}NSR
* The currentPage to set. }<:}XlwT%
*/ /qw.p#
publicvoid setCurrentPage(int currentPage){ QS`]
this.currentPage = currentPage; 1h5 Akq
} vZ Lf
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/** e96k{C`j0
* @return &cTU
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* Returns the everyPage. FVBYo%Ap
*/ }ad|g6i`
publicint getEveryPage(){ ovV'VcUs
return everyPage; R G`1en
} =g|FT
=tY T8Q;al
/** |Q>IrT
* @param everyPage 9&NgtZpt
* The everyPage to set. >LuYHr
*/ #_ lDss
publicvoid setEveryPage(int everyPage){ e>7i_4(C
this.everyPage = everyPage; 4KrL{Z+}
} T6k0>[3xf
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/** Aiea\jBv
* @return t#"Grk8Mz&
* Returns the hasNextPage. {l>hMxij
*/ <54
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publicboolean getHasNextPage(){ Y6d@h? ht
return hasNextPage; ,Y48[_ymm
} Du){rVY^d
sx<%2
/** %~S&AE-
* @param hasNextPage DlNX 3
* The hasNextPage to set. |^H5^k "Bv
*/ ;*&-C9b
publicvoid setHasNextPage(boolean hasNextPage){ Wv/=O}
this.hasNextPage = hasNextPage; @s^-.z
} RpYERAgT
o _H`o&xr
/** pD]OT-8
* @return ~u+9J}
* Returns the hasPrePage. N}YkMJy
*/ ~e.L.,4QZ8
publicboolean getHasPrePage(){ gPc=2
return hasPrePage; I++. ee
} 7t_^8I%[
8HdAFRw
/** -|\ZrE_h
* @param hasPrePage ^sg,\zD 'X
* The hasPrePage to set. sn>~O4"
*/ Ecx<OTo
publicvoid setHasPrePage(boolean hasPrePage){ WMP,\=6k0
this.hasPrePage = hasPrePage; ,6W>can
} HUO j0T
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/** #cLBQJq
* @return Returns the totalPage. BFW&2
* +d-NL?c
*/ yR.Ong
publicint getTotalPage(){ 76` .Y
return totalPage; L4?IHNB
} 5rUdv}.
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/** ^/=KK:n~
* @param totalPage k-""_WJ~^
* The totalPage to set. 7j)8Djzp|
*/ W`*r>`krVJ
publicvoid setTotalPage(int totalPage){ 7T'B6`-Ox
this.totalPage = totalPage; r!{Up7uL
} FU<Jp3<%
7vj2
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} dGTsc/$
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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 pFz`}?c0
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个PageUtil,负责对Page对象进行构造: uA#;G/$
java代码: {cw /!B
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/*Created on 2005-4-14*/ gbagi+8s`%
package org.flyware.util.page; _oDz-
vgN&K@hJ
import org.apache.commons.logging.Log; ROZF)|l
import org.apache.commons.logging.LogFactory; @!d{bQd,
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/** efE.&]
* @author Joa 9k[9P;"F:
* 8qu6.
*/ n@[O|?S
publicclass PageUtil { %GIr&V4|
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privatestaticfinal Log logger = LogFactory.getLog "Os_vlapHo
ps DetP
(PageUtil.class); Xm2z}X(%
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/** 26x[X.C:
* Use the origin page to create a new page 1 I",L&S1
* @param page {P#|zp 4C{
* @param totalRecords U\!X,a*ts{
* @return CQDkFQq-dq
*/ -1ub^feJ,
publicstatic Page createPage(Page page, int *bpD`s
@
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totalRecords){ Tkgs]q79
return createPage(page.getEveryPage(), IRqy%@)
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page.getCurrentPage(), totalRecords); )TM4R)r%)9
} i8HTzv"J
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/** DrK{}uM
* the basic page utils not including exception y Fq&8 x<X
;@E$}*3[>V
handler LvYB7<zk>
* @param everyPage -!]ZMi9
* @param currentPage ?p8_AL'RS
* @param totalRecords >t_6B~x9
* @return page 5rZ
*/ t}tEvh
publicstatic Page createPage(int everyPage, int G?Hdq;
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currentPage, int totalRecords){ /fV;^=:8c
everyPage = getEveryPage(everyPage); ?#UO./ "
currentPage = getCurrentPage(currentPage); OprkR
int beginIndex = getBeginIndex(everyPage, )p%E%6p
w$-6-rE]d
currentPage); S#}
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int totalPage = getTotalPage(everyPage, )q3p-)@kQ
YLn?.sV{[0
totalRecords); Z0r?|G0
boolean hasNextPage = hasNextPage(currentPage, i&GH/y
Xh;#
totalPage); zjoq6
boolean hasPrePage = hasPrePage(currentPage); e6RPIg
Qv/=&_6
returnnew Page(hasPrePage, hasNextPage, *<ewS8f*6
everyPage, totalPage, *$ %a:q1U
currentPage, UByv?KZi
]- QA'Lq
beginIndex); ,:\|7 F
} TT3|/zwn
\d$!a5LF}
privatestaticint getEveryPage(int everyPage){ mF^v ~
return everyPage == 0 ? 10 : everyPage; _n>,!vH
} AbmAKA@
EG |A_m85
privatestaticint getCurrentPage(int currentPage){ wz ~d(a#
return currentPage == 0 ? 1 : currentPage; PBkt~=j
} ,{?%m6.lE
}Y36C.@H
privatestaticint getBeginIndex(int everyPage, int vn"{I&L+w0
!ff&W1@
currentPage){ $(>+VH`l
return(currentPage - 1) * everyPage; RF0HjgP
} O#S.n#{
Pw!MS5=r
privatestaticint getTotalPage(int everyPage, int ChXq4]
-Wi` G
totalRecords){ p|D/;Mk
int totalPage = 0; 9|CN8x-
BbS4m
if(totalRecords % everyPage == 0) l3F6AlPql
totalPage = totalRecords / everyPage; Jz
*;q~
else \7'{g@C(
totalPage = totalRecords / everyPage + 1 ; ?"g2v-jTK
JbQ) sp
return totalPage; 6 3,H{
} I,@6J(9
Sa;qW3dt3E
privatestaticboolean hasPrePage(int currentPage){ tS8u
return currentPage == 1 ? false : true; W'+:'_{ j:
} n3
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_8UDT^?8,
privatestaticboolean hasNextPage(int currentPage, u.Tcg^ v
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int totalPage){ ]G< Vg5
return currentPage == totalPage || totalPage == a ]tVd#
Px`!A EFd[
0 ? false : true; Q9G;V]./
} xLH)P<^`C
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Y,t={HiclX
} ,0HRAmG
F,)%?<!I
j*TYoH1
2Gaa(rJ5o
6]%sFy2
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 *U=s\
pYZ6e_j1~
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 ;
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at
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做法如下: =CVB BuVy
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 'K{Z{[s{
:I^;jdL
的信息,和一个结果集List: x-.?HS[
java代码: ILShd)]Rw
vJOw]cwq
XtSkh] #z!
/*Created on 2005-6-13*/ uurh??R
package com.adt.bo; dZ0vA\z|
s
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import java.util.List; O]Qd<%V'x
3Xy-r=N. l
import org.flyware.util.page.Page; en*GM}<V
G`BU=Fi
/** J B]q
* @author Joa iaE^a^*
*/ H{?vbqQ
publicclass Result { g0Gf6o>2
0Bi.6r
private Page page; e 5*hE
OL,TFLn4
private List content; ^qQZT]
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/** \k!{uRy'
* The default constructor 8=uu8-l8g
*/ x$Oq0d{T
public Result(){ n!xt5=xP{
super(); /Uy"M:|V1
} 9}F*P669f
Vi]W |bP
/** kbMWGB%;
* The constructor using fields OO*zhGD;[
* d,Yw5$i
* @param page P&ptJtNg
* @param content 6'G6<8>-
*/ Jx](G>F4f1
public Result(Page page, List content){ yS(fILV
this.page = page; 8sM|%<$=j
this.content = content; EL 8<U
}
sAS:-wp
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/** sjwo/+2
* @return Returns the content. 9s$CA4?HP
*/ [b>Fn%y
publicList getContent(){ >A"v ed8
return content; ![_*(8v}S
} \T :i{.i
6BbGA*%{
/** |G,tlchprs
* @return Returns the page. "(z5{z?S
*/ vyX\'r.~7
public Page getPage(){ ADP%QTdqFJ
return page; Et/\xL
} @As[k2
c[4i9I3v
/** v>Yb/{A
* @param content <[\`qX
* The content to set. v|%Z+w
*/ '~[d=fwH
public void setContent(List content){ e2t-4}
ww
this.content = content; *|>d
} dDGgvi|[Mz
EwC{R`
/** 33ef/MElD$
* @param page 6dN7_v)
* The page to set. -vR5BMy=
*/ '\ey<}?5V
publicvoid setPage(Page page){ A1D^a,
this.page = page; 9m<jcxla$
} PHXZ=A+
} !K}~/9Z=m
(ehK?6[
`W:%mJd9
?:8ido#-
+*T7@1
2. 编写业务逻辑接口,并实现它(UserManager, Dhw(#{N
UU mTOJr
UserManagerImpl) 2w_W Adi
java代码: Ax?y
O%(fx!c`
kabnVVn~
/*Created on 2005-7-15*/ D!NQ~'.a=2
package com.adt.service; mdmvT~`
!tMuuK?IL=
import net.sf.hibernate.HibernateException; BJB^m|b)
g -HN
import org.flyware.util.page.Page; P+PR<ZoI{f
Xti[[s J
import com.adt.bo.Result; O[s{ Gk'>
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/** eg?<mKrZ
* @author Joa Hl/
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*/ BuWHX>H
publicinterface UserManager { C8e
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V=qwwYz~
public Result listUser(Page page)throws K[Kh&`T
&7b|4a8B%
HibernateException; TI#''XCB5
?hM>mL
} {7;8#.S72
UXugRk%d
V_RTI.3p
E4W -hq~
2FF4W54I
java代码: 8:>1F,
OjF_ %5
u7[ykyV
/*Created on 2005-7-15*/ 9:,\gw>F
package com.adt.service.impl; |e?64%l5P
,TPISs
import java.util.List; g[Ib,la_a
ang~<
import net.sf.hibernate.HibernateException; Xr2ou5zAn
/X(t1 +
import org.flyware.util.page.Page; 8X`tU<Ab
import org.flyware.util.page.PageUtil; pr#z=vqH
WObvbaK
import com.adt.bo.Result; Vf'd*-_!Q<
import com.adt.dao.UserDAO; Jd(,/q
import com.adt.exception.ObjectNotFoundException; IOoz^/'
import com.adt.service.UserManager; j!4et;
a1.Ptf eW|
/** _$f9]bab
* @author Joa ]*FVz$>XM
*/ U,gti,IX^
publicclass UserManagerImpl implements UserManager { Ph}|dGb
%D8ZO0J7H
private UserDAO userDAO; 7L@K _ZJ
M^iU;vo
/** RIE5KCrGB
* @param userDAO The userDAO to set. iz?tu: \v&
*/ /yF QeE
publicvoid setUserDAO(UserDAO userDAO){ jhu&&==\f
this.userDAO = userDAO; CkD#/
} ;SaX;!`39+
Y&_&s7z
/* (non-Javadoc) {R61cD,n
* @see com.adt.service.UserManager#listUser ?jt}*q>X]
&A)B~"[~
(org.flyware.util.page.Page) A~+S1
*/ '|*?*6q
public Result listUser(Page page)throws Yd= a}T
9^Whg~{
HibernateException, ObjectNotFoundException { >teOm?@U
int totalRecords = userDAO.getUserCount(); )m{Ye0!RD
if(totalRecords == 0) AUNQA
throw new ObjectNotFoundException $m+sNEAa
UIAj]
("userNotExist"); S_v'hlrrT
page = PageUtil.createPage(page, totalRecords); 9Xl5@%uz?z
List users = userDAO.getUserByPage(page); &jczO-R^
returnnew Result(page, users); +|@rD/I6
} l)w Hl%p
w'fT=v)
} DUe&r,(4O
E)7F\ w
S:q3QgU=X
.G(llA}
$w0lrh[+
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 @qjfZH@
;9ly'<up
询,接下来编写UserDAO的代码: nJ"YIT1K]p
3. UserDAO 和 UserDAOImpl: 3a 1 u
java代码: ?wF'<kEH
|),'9
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/*Created on 2005-7-15*/ M=*bh5t%]
package com.adt.dao; x^y" <
qYf |Gv
import java.util.List; 7 aYn0_NKp
MXiQ1x
import org.flyware.util.page.Page; U_$qi
@~"anqT`
import net.sf.hibernate.HibernateException; hf<^/@^tK
.tmiQ.
/** N!x =eC
* @author Joa 6uKMCQ=h
*/ /c-r
publicinterface UserDAO extends BaseDAO { ~-t>z
UMp/\&0
publicList getUserByName(String name)throws A@D2+fS
3
M10fI?
HibernateException; 8kt5KnD2
Ev2HGU [
publicint getUserCount()throws HibernateException; }%`~T>/
A'K%WW*'U
publicList getUserByPage(Page page)throws #nO|A\N
j.ldaLdG
HibernateException; kR@Yl Yo
G #T<`>T
} B_l{<
m6yIR6H
8W+gl=C~
p,<&zHb>K
`)h6j)xiQ
java代码: J~iBB~x.
p!V>XY'N^
Z,;cCxE
/*Created on 2005-7-15*/ ror|R@;y
package com.adt.dao.impl; %Lrd6i_j
Enq|Y$qm
import java.util.List; T<joRR
0T5=W U
import org.flyware.util.page.Page; =!UR=Hq
/.eeO k
import net.sf.hibernate.HibernateException; nL}5cPI
import net.sf.hibernate.Query; <0.$'M~E
C*te^3k>B
import com.adt.dao.UserDAO; `L5~mb;7*
h~,JdDV8l*
/** qr50E[
* @author Joa \^K&vW;
*/ xwZ8D<e-,
public class UserDAOImpl extends BaseDAOHibernateImpl YyJPHw)Z
SL&hJs4c'
implements UserDAO { H{c?lT
Tv]<SI<B[
/* (non-Javadoc) ]$
b<Gs
* @see com.adt.dao.UserDAO#getUserByName vhT_=:x
o{kbc5_
(java.lang.String) HygY>s+3[
*/ 5Wj;
[2
)
publicList getUserByName(String name)throws %T=A{<[`
zT* .jv
HibernateException { +wk`;0s A
String querySentence = "FROM user in class N_Af3R1_
^, i>'T
com.adt.po.User WHERE user.name=:name"; Na,_
Query query = getSession().createQuery `C+HE$B
ixh47M
(querySentence); O0*e)i8
query.setParameter("name", name); ZRUhAp'<qj
return query.list(); "$5\,
} `}no9$l~
Hj1
EGCA
/* (non-Javadoc) 7j i=E";.w
* @see com.adt.dao.UserDAO#getUserCount() _0 snAt^iC
*/ ]AS"z<
publicint getUserCount()throws HibernateException { /Go
K}W}
int count = 0; Uo_tUp_Q
String querySentence = "SELECT count(*) FROM ]Lqt(c
p'?w2YN/
user in class com.adt.po.User"; 8{Fm[
%"
Query query = getSession().createQuery 8?Y['
i~{
_eQV
(querySentence); ,Ci/xnI
count = ((Integer)query.iterate().next A?"h@-~2
w*w?S
()).intValue(); E}Xka1 Bn
return count; N(3R|Ii
} r\9TMg`C
=FBpo2^QB;
/* (non-Javadoc) qkP/Nl. u
* @see com.adt.dao.UserDAO#getUserByPage AdoZs8Q
w,j cm;
(org.flyware.util.page.Page) D~&Mwsi
*/ iY/KSX^~O
publicList getUserByPage(Page page)throws o8FXqTUcs4
q cA`)j
HibernateException { <<|H=![
String querySentence = "FROM user in class qq0?e0H
Y&r]lD
com.adt.po.User"; h#Ce_,o
Query query = getSession().createQuery Cw,D{
h:Ndzp{
(querySentence); {- 63/z
query.setFirstResult(page.getBeginIndex()) _2mNTJiw
.setMaxResults(page.getEveryPage()); vV`|!5x
return query.list(); C;\VO)]t
} Y5!b)vke
g42R 'E%
} |AH@ EI>
3@O0^v-
?Zyok]s
r7!J&8;{K
JK~ m(oQ
至此,一个完整的分页程序完成。前台的只需要调用 P-JfV 7(O8
+ydm,aKk
userManager.listUser(page)即可得到一个Page对象和结果集对象 WA.\*Nqz e
4W\,y_Q o
的综合体,而传入的参数page对象则可以由前台传入,如果用 ]Bb7(JX
mKg@W;0ML
webwork,甚至可以直接在配置文件中指定。 ke.7Zp2.R
JF qf;3R
下面给出一个webwork调用示例: "gNK><
java代码: <3 j~=-
h K}bj
2neRJ
/*Created on 2005-6-17*/ ]?9[l76O7
package com.adt.action.user; ^^$vR[7
#Y,A[Y5jX
import java.util.List; .Tm- g#
[7"}=9
import org.apache.commons.logging.Log; Zy wK/D
import org.apache.commons.logging.LogFactory; IB7tAG8
import org.flyware.util.page.Page; T }uE0Z,
{=At#*=A
import com.adt.bo.Result; G79C {|c\
import com.adt.service.UserService; H$-$2?5
import com.opensymphony.xwork.Action; 1BD6l2y
+
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/** VvgN3e[
* @author Joa $M]%vG
*/ A"/aGCG0z
publicclass ListUser implementsAction{ >7>7/7=O
+|nsu4t,<
privatestaticfinal Log logger = LogFactory.getLog +X!+'>
.9\Cy4_qSd
(ListUser.class); S+*cbA{J|
;x>;jS.t
private UserService userService; ~!
Lw1]&
.{N\<