Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 m1IKVa7-\}
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 k~/>b~.c
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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 }->.k/vc
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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 E%'~'[Q
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分页支持类: F! X}(N?t
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java代码: sU"}-de
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package com.javaeye.common.util; (__yh^h:m
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import java.util.List; #CnHf
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publicclass PaginationSupport { shH~4<15
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publicfinalstaticint PAGESIZE = 30; iajX ~kv
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privateint pageSize = PAGESIZE; NziZTU}
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privateList items; -\y-qHgb/
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privateint totalCount; o d7]tOK9
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privateint[] indexes = newint[0]; cDoo*
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privateint startIndex = 0; k` {@pt.
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public PaginationSupport(List items, int X/;p-KX
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totalCount){ * FeQ*`r
setPageSize(PAGESIZE); -@F fU2
setTotalCount(totalCount); `?y<>m*
setItems(items); -3&G"hfK
setStartIndex(0); M^7MU}5w
} rFZrYm
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public PaginationSupport(List items, int jr /lk
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totalCount, int startIndex){ O Lc}_
setPageSize(PAGESIZE); Ka|eFprS
setTotalCount(totalCount); jS!`2li?{
setItems(items); `' 153M]
setStartIndex(startIndex); s3 ;DG
} <|*'O5B
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public PaginationSupport(List items, int MzYavg`
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totalCount, int pageSize, int startIndex){ "0EA;S8$8
setPageSize(pageSize); d$Y7u
setTotalCount(totalCount); tURc bwV
setItems(items); Fa epDjY8
setStartIndex(startIndex); m3^/:<
} {3Y )rY!z
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publicList getItems(){ 3:5DL!Sm8J
return items; \#rO!z
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} CN2_bz
*<'M!iRC
publicvoid setItems(List items){ o]LRzI
this.items = items; /EMJSr
} 1mSaS4!"B
vZ#!uU^a:
publicint getPageSize(){ f7hXQ|$
return pageSize;
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} \]Dt4o*yZ
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publicvoid setPageSize(int pageSize){ d vOJW".
this.pageSize = pageSize; i1oKrRv
} M0c9pE
*RR[H6B^]X
publicint getTotalCount(){ UkfB^hA
return totalCount; +<.\5+
} -#29xRPk
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publicvoid setTotalCount(int totalCount){ .A1\J@b
if(totalCount > 0){ e#/kNHl
this.totalCount = totalCount; kzq29S
int count = totalCount / ]feyJLF
3"UsZyN:
pageSize; v8I{XU@%
if(totalCount % pageSize > 0) ibdO*E
count++; '+*-s7o{
indexes = newint[count]; &*&?0ov^"
for(int i = 0; i < count; i++){ Q0{z).&\(e
indexes = pageSize * tJ=di5&
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i; p8+/\Ee]B
} ~"!a9GZ
}else{ DP7C?}(
this.totalCount = 0; 3P <'F2o
} [B0K
} [rreFSy#@
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publicint[] getIndexes(){ ^*^/]vM
return indexes; uO >x:*^8
} 'FzN[% K"
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publicvoid setIndexes(int[] indexes){ M;Wha;%E"
this.indexes = indexes; )~rB}>^Z
} 4Z)DDz-}V
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publicint getStartIndex(){ }t>q9bZ9z
return startIndex; GIv){[i
} K`nJVc
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publicvoid setStartIndex(int startIndex){ HXJ9xkrr
if(totalCount <= 0) -U>7
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this.startIndex = 0; (tl}q3U
elseif(startIndex >= totalCount) rwpgBl
this.startIndex = indexes .h;Se
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[indexes.length - 1]; t#<KxwhcN
elseif(startIndex < 0) 5]7&IDA]]9
this.startIndex = 0; '5};M)w
else{ 3D)b*fPc
this.startIndex = indexes L8V3BH7B
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[startIndex / pageSize]; (Q-I8Y8l8
} S;A)C`X&
} mjEs5XCC"
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publicint getNextIndex(){ o6?l/nJ
int nextIndex = getStartIndex() + 2[dIOb4b
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pageSize; FBsn;,3<W
if(nextIndex >= totalCount) /qxJgoa
return getStartIndex(); ,.g}W~S)
else o&^NwgRCF
return nextIndex; gKL1c{BV
} [xpQH?
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publicint getPreviousIndex(){ Dw |3Z
int previousIndex = getStartIndex() - \]Z&P,}w
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pageSize; hXX1<~k
if(previousIndex < 0) BDpF}
return0; <4zT;:NQ
else [F|+(}
return previousIndex; j;2<-{
} n6d^>s9J
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} *=vlqpG
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抽象业务类 Ko}2%4on
java代码: :pd&dg!5
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/** S!7g)
* Created on 2005-7-12 iMWW%@U^=
*/ \$;~74}
package com.javaeye.common.business; e~Hr(O+;e6
<F=Dj*]
import java.io.Serializable; p`GWhI?
import java.util.List; ek[kq[U9
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import org.hibernate.Criteria; ~|R[O^9B
import org.hibernate.HibernateException; 5.k}{{+
import org.hibernate.Session; S+FQa7k
import org.hibernate.criterion.DetachedCriteria; G&o64W;-s
import org.hibernate.criterion.Projections; ,U%=rfB~
import 0VIZ=-e
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org.springframework.orm.hibernate3.HibernateCallback; \/,g VT
import 1D$::{h
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org.springframework.orm.hibernate3.support.HibernateDaoS baIbf@t/
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upport; l<2oklo5
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import com.javaeye.common.util.PaginationSupport; & z gPN8u
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public abstract class AbstractManager extends .&chdVcxyS
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HibernateDaoSupport { QV/";A3k
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privateboolean cacheQueries = false; C<t RU5|
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privateString queryCacheRegion; 8&T,LNZoY
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publicvoid setCacheQueries(boolean -gSj>b7T
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cacheQueries){ "=ElCaP}
this.cacheQueries = cacheQueries; sJ7sjrEp1
} </yo9.
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publicvoid setQueryCacheRegion(String ,F}r@
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queryCacheRegion){ i7f%^7!
this.queryCacheRegion = fqX~xp
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queryCacheRegion; A^cU$V%?W
} B<+pg
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publicvoid save(finalObject entity){ XSl!T/d
getHibernateTemplate().save(entity); "<*nZ~nE)
} 8;8YA1@w
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publicvoid persist(finalObject entity){ gr\@sx?b
getHibernateTemplate().save(entity); <p)Z/
} lO_c/o$
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publicvoid update(finalObject entity){ /4H[4m]I
getHibernateTemplate().update(entity); 6s5b$x
} ,$BgR2^
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publicvoid delete(finalObject entity){ T\cR2ZT~
getHibernateTemplate().delete(entity); j Ii[
} s@z{dmL
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publicObject load(finalClass entity, S" {GlRpd
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finalSerializable id){ Y.9~Bo<<r
return getHibernateTemplate().load !Z-9tYO
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(entity, id); ;'hi9L
} Lb^(E-
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publicObject get(finalClass entity, >"bnpYSe
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finalSerializable id){ WT?b Bf
return getHibernateTemplate().get DH/L`$
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(entity, id); UE{,.s
} bk0Y
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publicList findAll(finalClass entity){ $^K]&Mft
return getHibernateTemplate().find("from p6 <}3m$
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" + entity.getName()); L=,Y1nO:p
} &:q[-K@!
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publicList findByNamedQuery(finalString joY1(Y
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namedQuery){ srsK:%`
return getHibernateTemplate Gxo#
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().findByNamedQuery(namedQuery);
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} |@+8]dy:l
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publicList findByNamedQuery(finalString query, 2q/nAQ+
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finalObject parameter){ Et)920
return getHibernateTemplate U|9U(il
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().findByNamedQuery(query, parameter); T^N L:78
} -!i;7[N
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publicList findByNamedQuery(finalString query, 2|$lk8 /,
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finalObject[] parameters){ 8znj~7}#
return getHibernateTemplate A"0wvk)UcY
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().findByNamedQuery(query, parameters); >H)^6sJ;%b
} {zY`h6d
@T5YsX]qb7
publicList find(finalString query){ ^g70AqUc
return getHibernateTemplate().find 8g.AT@ ,Q
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(query); cJSVT8
}
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publicList find(finalString query, finalObject U)
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parameter){ pn|p(6
return getHibernateTemplate().find DL
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(query, parameter); _k6x=V;9g
} DakLD~H;
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public PaginationSupport findPageByCriteria p
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(final DetachedCriteria detachedCriteria){ k\nH&nb
return findPageByCriteria fE'-.nA+
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); /SbSID_a
} {ms,q_Zr
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public PaginationSupport findPageByCriteria ht2
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(final DetachedCriteria detachedCriteria, finalint 7WgIhQ~
t'dHCp}
startIndex){ (D0C#<4P
return findPageByCriteria WC3W+v G7
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(detachedCriteria, PaginationSupport.PAGESIZE, S@9w'upd
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startIndex); &t~zD4u B
} bK!,Pc<
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public PaginationSupport findPageByCriteria }Q!h ov
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(final DetachedCriteria detachedCriteria, finalint 3w
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pageSize, g8LT7
finalint startIndex){ gTqeJWX9wP
return(PaginationSupport) N-XVRuv
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getHibernateTemplate().execute(new HibernateCallback(){ ay=KfY5
publicObject doInHibernate q1U&vZ3]c
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(Session session)throws HibernateException { +fC#2%VnU
Criteria criteria = /_$~rW
l#X=]xQf
detachedCriteria.getExecutableCriteria(session); L@>^_p$
int totalCount = \d `dV0X
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((Integer) criteria.setProjection(Projections.rowCount NS7@8 #C
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()).uniqueResult()).intValue(); E}]I%fi
criteria.setProjection F5<"ktnI
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(null); ;[FW!
List items = xN e_qO
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criteria.setFirstResult(startIndex).setMaxResults >{j,+$%kp
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(pageSize).list(); eFt\D\XOW
PaginationSupport ps = Z[a O_6L
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p
new PaginationSupport(items, totalCount, pageSize, j5PaSk&o=
4}.WhE|h
startIndex); di8W2cwz
return ps; .tZjdNE(h
} wrz+2EP`
}, true); \Ku9"x
} `
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public List findAllByCriteria(final [54@i rH
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DetachedCriteria detachedCriteria){ [>b
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return(List) getHibernateTemplate 2q`)GCES~
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().execute(new HibernateCallback(){ Ul'~opf
publicObject doInHibernate c+@d'yR
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(Session session)throws HibernateException { #g@
Criteria criteria = 4(` 2#
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detachedCriteria.getExecutableCriteria(session); hg%@ W
return criteria.list(); T)b3N|ONB
} iifc;6 2
}, true); a"`g"ZRx
} Z_iAn TT
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public int getCountByCriteria(final F3kC"H
S% JNxT7'
DetachedCriteria detachedCriteria){ &,W_#l{
Integer count = (Integer) 8vz_~p9%j
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getHibernateTemplate().execute(new HibernateCallback(){ SRA|7g}7W
publicObject doInHibernate 4q\.I+r^
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(Session session)throws HibernateException { :N^@a-
Criteria criteria = NWo7wVwc/c
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detachedCriteria.getExecutableCriteria(session); "wT~$I"
return cJU!zG
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criteria.setProjection(Projections.rowCount 5uQv
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()).uniqueResult(); qT4I Y$h
} zznPD%#Sc
}, true); ?;0nJf
return count.intValue(); Bxn8><
} pr0@sri@
} c[wQJc
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用户在web层构造查询条件detachedCriteria,和可选的 MZUF! B
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 QOkE\ro
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PaginationSupport的实例ps。 E3CiZ4=5
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ps.getItems()得到已分页好的结果集 iF#}t(CrH
ps.getIndexes()得到分页索引的数组 &rl]$Mtt
ps.getTotalCount()得到总结果数 E1Ru)k{B
ps.getStartIndex()当前分页索引 uPv;y!Lsa@
ps.getNextIndex()下一页索引 9#Aipu\
ps.getPreviousIndex()上一页索引 aBqe+FXp4
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 [a>JG8[,t
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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 !7IT~pO`
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一下代码重构了。 }#\;np
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我把原本我的做法也提供出来供大家讨论吧: v @$evmA
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首先,为了实现分页查询,我封装了一个Page类: D&z'tf5
java代码: jm#d7@~4
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/*Created on 2005-4-14*/ 9Sx<tj_4P{
package org.flyware.util.page; WTV3p,;6a
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/** X%4uShM
* @author Joa `5k6s,
* o@<6TlZM
*/ c:h.J4mv
publicclass Page { Ac5o K
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ew
/** imply if the page has previous page */ &J6o$i
privateboolean hasPrePage; RS||KA])J
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/** imply if the page has next page */ zulf%aaL
privateboolean hasNextPage; a O"nD_7
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/** the number of every page */ ctc`^#q
privateint everyPage; Z!*8JaMT
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/** the total page number */ u'$yYzBE
privateint totalPage; m]-v IUpb
A/$KA'jX
/** the number of current page */ A1k&`
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privateint currentPage; PNxVW
[/+dHW|
/** the begin index of the records by the current #U!(I#^3
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query */ 8CnI%_Su
privateint beginIndex; @R'g@+{I
9U }MXY0
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/** The default constructor */ \c9t]py<.h
public Page(){ 48~m=mI
l# !@{ <
} NDIc?kj~
p(x1D]#Z[
/** construct the page by everyPage ^O$[Y9~*
* @param everyPage +]S;U&vQ
* */ H4y1Hpa,
public Page(int everyPage){ So)KI_M
this.everyPage = everyPage; (v'lb!j^#
} _Y
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/** The whole constructor */ k@t,[
public Page(boolean hasPrePage, boolean hasNextPage, G3_mWppH
g<hv7?"[
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int everyPage, int totalPage, CQ8o9A/
int currentPage, int beginIndex){ U&w5&W{F}
this.hasPrePage = hasPrePage; j quSR=
this.hasNextPage = hasNextPage; w}bEufU+2
this.everyPage = everyPage; ^+-L;XkeY
this.totalPage = totalPage; $^NWzc
this.currentPage = currentPage; WfTdD.Xx
this.beginIndex = beginIndex; uG(~m_7Hx
} ,s yA()
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/** F;MT4*4
* @return <_sT]?N#
* Returns the beginIndex. cP#]n)<
*/ 8Snq75Q<
publicint getBeginIndex(){ )HzITsFZKT
return beginIndex; ~kj(s>xP
} #o r7T^
f<> YYeY
/** Xg!|F[i
* @param beginIndex $vw}p.
* The beginIndex to set. ,a]~hNR*X
*/ g]iy-,e
publicvoid setBeginIndex(int beginIndex){ Y%CL@G60
this.beginIndex = beginIndex; 5>1Y="B
} /H;kYx
>uPde5"ZF-
/** J%Z)#
* @return y`B!6p
5j
* Returns the currentPage. VI|DMx
*/ $p6Xa;j$ 9
publicint getCurrentPage(){ 2p3u6\y
return currentPage; q|
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} uDE91.pUkr
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/** @'<j!CqQ
o
* @param currentPage 1[gjb((
* The currentPage to set. P{i8
*/ <k-@R!K~JC
publicvoid setCurrentPage(int currentPage){ U70@}5!
this.currentPage = currentPage; R8r[;u\iV
} H`6Jq?\
S9"y@F
<
/** ANpY qV
* @return WlQ&Yau
* Returns the everyPage. ^$Eiz.
*/ =iK6/ y`
publicint getEveryPage(){ GaK_9Eg-2
return everyPage; E]eqvT NH
} [;CqvD<S
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/** ;DgX"Uzm
* @param everyPage 9CU6o:'fW
* The everyPage to set. ik:)-GV;s
*/ 3~3(G[w
publicvoid setEveryPage(int everyPage){ dI0>m:RBz
this.everyPage = everyPage; hA,rSq
} : {N3o:
f/[?5M[
/** !,JT91
* @return /DG`Hg
* Returns the hasNextPage. U9p.Dh~)vG
*/ x{`<);CQ
publicboolean getHasNextPage(){ |7Xpb
return hasNextPage; u FYQ^
} 7E75s)KH
!qGx(D{\
/** I`$I0
* @param hasNextPage hIO4%RQj_
* The hasNextPage to set. vzrD"
*/ #&2N,M!Q
publicvoid setHasNextPage(boolean hasNextPage){ sv{0XVn+^
this.hasNextPage = hasNextPage; ^Lv^W
} %J (
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yE|}
r
/** z.9FDQLp
* @return )Q
* Returns the hasPrePage. m2<
*
*/ soVZz3F
publicboolean getHasPrePage(){ PN^1
return hasPrePage; eGypXf%
} R
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y[@j0xlO
/** twHM~cTS
* @param hasPrePage ~S=fMv^BR
* The hasPrePage to set. [@)z $W
*/ gJFpEA {
publicvoid setHasPrePage(boolean hasPrePage){ $*)(8C l
this.hasPrePage = hasPrePage; 10I`AjF0
} b;;Kxi:7$}
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/** D%Jc?6/I#3
* @return Returns the totalPage. Pc;
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* 1>@|
*/ F-7b`cF9[r
publicint getTotalPage(){ KsU&<eQ
return totalPage; {_X1&&>8/
} "O1*uwm
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/** [#rdfN'?U
* @param totalPage eKFc
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* The totalPage to set. (xSi6EZ6;
*/ 8qYGlew,
publicvoid setTotalPage(int totalPage){ : )"jh`
this.totalPage = totalPage; f`]E]5?
} mhkAI@)>
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} qjEWk."
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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 +:Q/<^Z
1;~ 1U9V
个PageUtil,负责对Page对象进行构造: M j%|'dZz
java代码: 1z@# 8_@
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/*Created on 2005-4-14*/ QRh4f\fY
package org.flyware.util.page; nMdN$E
^5 =E`q".
import org.apache.commons.logging.Log; $JSC+o(q3#
import org.apache.commons.logging.LogFactory; QZa#iL
P7.8tM2}
/** +X(^Q@
* @author Joa 3pjYY$'
* Jas|P}{=fT
*/ {)gd|JV*
publicclass PageUtil { l3#dfW{
M9jo<+
privatestaticfinal Log logger = LogFactory.getLog #5:A?aj
Qg$Nj=Cw
(PageUtil.class); yy.:0:ema
U\ E{-7
/** }
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* Use the origin page to create a new page MkGq%AE`Y
* @param page V42*4hskL
* @param totalRecords 3$y L+%i
* @return @`8 B}
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*/ 18tQWI$
publicstatic Page createPage(Page page, int 3udIe$.Q
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totalRecords){ j!o3g;j
return createPage(page.getEveryPage(), "LIii1]k
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page.getCurrentPage(), totalRecords); Vd>.fb\U2
} TdIFZ[<7
+4nR&1z$
/** .EZ{d
* the basic page utils not including exception D#[ :NXahn
(E(:F[.S
handler j/mp.'P1k
* @param everyPage +Q]'kJ<s
* @param currentPage yB{o_1tc
* @param totalRecords ^o\p|f>f
* @return page dq/?&X
*/ 5@A=,
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publicstatic Page createPage(int everyPage, int Q~!hr0
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currentPage, int totalRecords){ ^&/&I9z
everyPage = getEveryPage(everyPage); .eXA.9|jm
currentPage = getCurrentPage(currentPage); 'J0s%m|j
int beginIndex = getBeginIndex(everyPage, hg=G//
w$:)wyR-
currentPage); =usDI<3r
int totalPage = getTotalPage(everyPage, _`[6jhNa!
#$B,8LFz,$
totalRecords); yzR=:0J
boolean hasNextPage = hasNextPage(currentPage, U`_vF~el~
)&!@O$RS8(
totalPage); KY&,(z
boolean hasPrePage = hasPrePage(currentPage); W@C tF U9
mg/kyua^
returnnew Page(hasPrePage, hasNextPage, !:[n3.vm
everyPage, totalPage, NRF%Qd8I/2
currentPage, wggHUr(g,
?s} E<Kr
beginIndex); <@!kR$Rd
} .(]1PKW
/G+gk0FW
privatestaticint getEveryPage(int everyPage){ #R4KBXN
return everyPage == 0 ? 10 : everyPage; % peb{i
} m1i$>9,
c} ET#2,
privatestaticint getCurrentPage(int currentPage){ cNc_
n<M
return currentPage == 0 ? 1 : currentPage; )K3
vzX
} j|dzd<kE6
IqKXFORiNI
privatestaticint getBeginIndex(int everyPage, int pv SFp-:_
uCS
currentPage){ JlGD.!`
return(currentPage - 1) * everyPage; 7]zZha4X
} 5mVu]T`
!sQ8,l0h
privatestaticint getTotalPage(int everyPage, int bxe 97]
K -1~K
totalRecords){ \ySc uT
int totalPage = 0;
NX_S
>*xzSd?\
if(totalRecords % everyPage == 0) ;FflEL<7Y
totalPage = totalRecords / everyPage; t3JPxg]0k'
else m48Y1'4
totalPage = totalRecords / everyPage + 1 ; Vn;]''_
oHnpw U
return totalPage; ()
;7+
} q#-H+7 5
~0Q72
privatestaticboolean hasPrePage(int currentPage){ i>zyn-CuW
return currentPage == 1 ? false : true; Dy@NgHe
} 4aKy]zPoE
ZM`_P!G
privatestaticboolean hasNextPage(int currentPage, <qt%MM [Y
)pa|uH+N
int totalPage){ 1*b%C"C
return currentPage == totalPage || totalPage == gRI|rDC)B
O G}&%NgH
0 ? false : true; Vs"Q-?
} %y+j~]^:
--)[>6)I
4FdH:os
} )E2Lf]
&r!>2$B\
E|3aiC,5
{z_pL^S'52
.6#2i <oPW
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。 M4\Io]}-M
7}.(EZ0
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 YWFHiB7x
f+AIxSw
做法如下: 2GS2,
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 0M -AIQ5
O0YGjS|d
的信息,和一个结果集List: 4q8%!\A+
java代码: $dw;Kj'\
'8
#*U
N3RwcM9+;
/*Created on 2005-6-13*/ -
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package com.adt.bo; n//a;m
)6WU&0>AU8
import java.util.List; WfZ#:G9
y&]D2"I
import org.flyware.util.page.Page; xGL"N1
QLl44*@
/** Fj4:_(%nG
* @author Joa 1+iiiVbMH
*/ 0X w?}
publicclass Result { W#\4"'=I
v*v&f!Ym&s
private Page page; Kn|dnq|G
)dcGV$4t[
private List content; *A`^ C
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/** Qz;"b!
* The default constructor rE~O}2a#H
*/ t[~i})yS
public Result(){ / KM+PeO
super(); !<ucwWY,
} tWIhbt
Y7HWf
/** YN[D^;}
* The constructor using fields '?t{-z,
*
t-/^ O
* @param page "p\KePc;@
* @param content gO36tc:ce
*/ 7\lc aC@
public Result(Page page, List content){ :;QLoZh^
this.page = page; [MG:Ym).2`
this.content = content; >TgO|mq
} P)
#rvTDRw
p*A//^wQ
/** Dl6zl6q?
* @return Returns the content. 1|CO>)*D
*/ 0c)19Ig
publicList getContent(){ YQJ_t@0C
return content; []NAV
} QH:i)v*
~Tolz H!
/** ;$]R#1i44
* @return Returns the page. WxdYvmp6z[
*/ a*`J]{3G
public Page getPage(){ $[e*0!e
return page; r@aFB@
} S7R^%Wck/6
WObfHAp.
/** .H"gH-I
* @param content V-57BKeDz
* The content to set. ( ;q$cKy
*/ Ff30%
public void setContent(List content){ IU/*YI%W
this.content = content;
NDi@x"];
} S5vJC-"
mc$dR,
H0
/** Sw~<W%! ?
* @param page N?p$-{
* The page to set. )erPp@
*/ DpAuI w7|
publicvoid setPage(Page page){ 5k @k
this.page = page; F7df
} 3[$VW+YV
} .KV?;{~q@
k<y$[xV
?*g]27f11
2C>PxA6l
$xqphhBg
2. 编写业务逻辑接口,并实现它(UserManager, F-t-d1w6
~ lS3+H
UserManagerImpl) M II]sF
java代码: >r3Wo%F'
s_|wvOW)'
4YJs4CB
/*Created on 2005-7-15*/ LQ._?35r
package com.adt.service; );C !:?
;J<kG@
import net.sf.hibernate.HibernateException; :&]%E/
:
f Wh7X3
import org.flyware.util.page.Page; f3O3pIA
K>-m8.~\E
import com.adt.bo.Result; 6Dch+*4*@
>13= 4S
/** }
?
* @author Joa :98Pe6
*/ l#%w,gX
publicinterface UserManager { na~ r}77o
$W)FpN;CW/
public Result listUser(Page page)throws ?mMd6U&J
7be?=c)+"
HibernateException; ) ":~`Z*@
SU:Cm:$
} .w`8_v &Y
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+`ZcYLg)#
java代码: xH0Bk<`V:
M@.1P<:h
5D'8 l@7
/*Created on 2005-7-15*/ A="h}9ok
package com.adt.service.impl; JprZ6
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import java.util.List; @0aUWG!k
$0WAhq
import net.sf.hibernate.HibernateException; s%Z3Zj(,8(
mZORV3bN
import org.flyware.util.page.Page; ,ihTEw,t(
import org.flyware.util.page.PageUtil; a/_ `1
3Z`oI#-x
import com.adt.bo.Result; 4Hu.o 7
import com.adt.dao.UserDAO; pB )nQ5l'
import com.adt.exception.ObjectNotFoundException; 6(wpf^br2
import com.adt.service.UserManager; 1iz\8R:0
sI`Lsd'V
/** oo2VT
* @author Joa ^LZU><{';
*/ "jy'Dpy0m
publicclass UserManagerImpl implements UserManager { atYm.qb
K@hv[4
private UserDAO userDAO; ")TI,a`
|*!I(wm2i
/** z\v\T|C
* @param userDAO The userDAO to set. 5}1c Np6@
*/ rZ^DiFR
publicvoid setUserDAO(UserDAO userDAO){ QjPcfR\
this.userDAO = userDAO; ' e-FJ')|
}
N3E=t#n
o zv><e#
/* (non-Javadoc) Lq yY??\@
* @see com.adt.service.UserManager#listUser _m@QeO'yh
K'y;j~`-
(org.flyware.util.page.Page) :.@gd7T
*/ z}Xn>-N-
public Result listUser(Page page)throws ?g!py[CrE
norWNm(n
HibernateException, ObjectNotFoundException { h!$W^Tm2g
int totalRecords = userDAO.getUserCount(); :?&N/7
if(totalRecords == 0) 7D4P=$UJp
throw new ObjectNotFoundException }F-W OQ
/QG8\wXE2
("userNotExist"); #b:8-Lt:M
page = PageUtil.createPage(page, totalRecords); kz+P?mopm
List users = userDAO.getUserByPage(page); Hl] 3F^{
returnnew Result(page, users); .'
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} ^oj)#(3C
=6/0=a[
} r..\(r
7j5 l?K-
N[czraFBD}
c8#A^q}
UnGG%
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 53#7Yy
;A1pqHr
询,接下来编写UserDAO的代码: Ig]Gg/1G
3. UserDAO 和 UserDAOImpl: \9!W^i[+
java代码: ;g*ab
S.BM/M
1S <V,9(
/*Created on 2005-7-15*/ fH>]>2fS
package com.adt.dao; HA>b'lqBM
wR1M_&-s
import java.util.List; $TWt[
:FB#,AOa_
import org.flyware.util.page.Page; ?~;G)5
~[Mm0L}8
import net.sf.hibernate.HibernateException; kpcIU7|e
GKSfr8US4
/** 8 yQjB-,#
* @author Joa 2BEF8o]Np
*/ 90&ld :97
publicinterface UserDAO extends BaseDAO { In5'(UHW:
eXUXoK=T
publicList getUserByName(String name)throws : >4{m)
j$a,93P5
HibernateException; Ar N *9
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publicint getUserCount()throws HibernateException; 8v_HIx0xu
\_qiUvPf\
publicList getUserByPage(Page page)throws \2@OS6LUe
IZoa7S&t
HibernateException; \5cAOBja
._Wm%'uX
} Z25^+)uf*U
pS;jrq
I#
j-ZKEA{:1
I HgYgn
`XS6t)!ik
java代码: UJ<eF/KSmG
~Qeyh^wo
kTt;3 Ia
/*Created on 2005-7-15*/ OpA
package com.adt.dao.impl; q3#07o_dV
CQ9B;i`
import java.util.List; 9;NR
*^ g7kCe(
import org.flyware.util.page.Page; T]Pp\6ff
L]I)E`s
import net.sf.hibernate.HibernateException; 5v<BB`XWp
import net.sf.hibernate.Query; _0<qS{RW
XOAZ
import com.adt.dao.UserDAO; .A//Q|ot!
76(-!Z@=J
/** TU&gj1
* @author Joa "WV]|
TS"]
*/ q4C$-W%rj
public class UserDAOImpl extends BaseDAOHibernateImpl HNu/b)-Rb
<p;cR` %uE
implements UserDAO { [/.o>R#J(
80U07tJ
/* (non-Javadoc) LzEs_B=9
* @see com.adt.dao.UserDAO#getUserByName >LRt,.hy6
:)_Ap{9J
(java.lang.String) X!Xl
*/ Y<0
[_+(
publicList getUserByName(String name)throws LS}dt?78`V
/:iO:g1
HibernateException { -Zh`h8gX
String querySentence = "FROM user in class GcmN40
`}Ssc-A
com.adt.po.User WHERE user.name=:name"; RoFy2A=_
Query query = getSession().createQuery }J$Q
x'tYf^Va28
(querySentence); n$i}r\
so
query.setParameter("name", name); bX23F?
return query.list(); \#Ez["mD
} sS7r)HV&GI
VC,wQb1J/
/* (non-Javadoc) ?{ns1nW:
* @see com.adt.dao.UserDAO#getUserCount() I'%vN^e^
*/
qc;9{$?xV
publicint getUserCount()throws HibernateException { &_n~# Mex
int count = 0; l$=Y(Xk
String querySentence = "SELECT count(*) FROM f^\qDvPur
Q5b~5a
user in class com.adt.po.User"; F?TxViL
Query query = getSession().createQuery Z6#}6Y{
L?T%;VdG'>
(querySentence); wyvrNru<l4
count = ((Integer)query.iterate().next M}MXR=X,
O:3LA-vA
()).intValue(); ~OO&%\$k
return count; {PZNJ 2~
} {L^b['h@
K"B2
SsC
/* (non-Javadoc) \q(DlqTqs
* @see com.adt.dao.UserDAO#getUserByPage H}5zKv.T
{fW(e?8)
(org.flyware.util.page.Page) /X>Fn9mM
*/ Pi7vuOJr8
publicList getUserByPage(Page page)throws pVbgjJI
gx~79;6
HibernateException { /ZlPEs)
String querySentence = "FROM user in class hDTiXc
c~bi
~ f
com.adt.po.User"; 3}V`]B#a
Query query = getSession().createQuery X;25G
4
qMO@E_
(querySentence); +c$]Q-(
query.setFirstResult(page.getBeginIndex()) uSh!A
.setMaxResults(page.getEveryPage()); %5.aC|^}
return query.list(); huVw+vAA
} .4P5tIn\
DdJ>1504
} B@XnHh5y
b /65Q&g'
WxwSb`U|
_EMq"\ND
g#b[-)Qx
至此,一个完整的分页程序完成。前台的只需要调用 r:Uqtqxh
/ ;>U0~K
userManager.listUser(page)即可得到一个Page对象和结果集对象 K8xwPoRL
G&8)5d[
的综合体,而传入的参数page对象则可以由前台传入,如果用 {nTQc2T?;
Uv|z
c
webwork,甚至可以直接在配置文件中指定。 VQA}! p
|L|)r)t
下面给出一个webwork调用示例: "#Ov!t
java代码: ]gI>ay"\QA
49.
@Uzo
1haNca_6,
/*Created on 2005-6-17*/ <5rs~
package com.adt.action.user; #m
yiZL%
&s m7R i
import java.util.List; HRP4"#9R
]r++YIg!j
import org.apache.commons.logging.Log; 4JF)w;X}
import org.apache.commons.logging.LogFactory; mHcxK@qw
import org.flyware.util.page.Page; e`gOc*
IRy!8A=X
import com.adt.bo.Result; fT9z 4[M
import com.adt.service.UserService; uLFnuK
import com.opensymphony.xwork.Action; rz/^_dV
A0Z<1|6r*
/** &+F|v(|r
* @author Joa .
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*/ F-K=Otj
publicclass ListUser implementsAction{ F~j
U; L
/ O@'XWW
privatestaticfinal Log logger = LogFactory.getLog !J<}=G5
{c5%.<O
(ListUser.class); m?LnO5Vs
Gd^K,3:. T
private UserService userService; LvP{"K;
|KSd@
private Page page; N$#518
4-lG{I_S:
privateList users; 8w,U[aJm
$r0~&$T&
/* *]uo/g
* (non-Javadoc) LObS
7U
* Bqo8G->
* @see com.opensymphony.xwork.Action#execute() Y4E UW%
*/ Tc{r;:'G<
publicString execute()throwsException{ w#V{'{DKp
Result result = userService.listUser(page); nT
UKA
page = result.getPage(); )nJo\HFXv
users = result.getContent(); % H"A%
return SUCCESS; 1O" Mo
} yL =*yC
]WZ_~8
/** Ml &Cr
* @return Returns the page. r0
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*/ A4!IbJD,0
public Page getPage(){ nsO!
return page; ~3p
:jEM.[
} r8PXdNg
Z:F5cXt<
/** %C&HR2
* @return Returns the users. `LD#fg*
*/ 8S;]]*cD~
publicList getUsers(){ ;O8Uc&:P
return users; m e\S:
} G)qNu }
+<cvyg5U
/** w[g(8#*
* @param page yO@KjCv"
* The page to set. m~KGB"
*/ w]n ,`r^
publicvoid setPage(Page page){ %3v:c|r
this.page = page; G/Ll4
:
} B+e$S%HV
u$T`Bn
/** 3&*_5<t\X
* @param users "YIrqk
* The users to set. vfb~S~|U6g
*/ B(}u:[
b^S
publicvoid setUsers(List users){ i1ph{;C
this.users = users; &V.ps1
} F_8<
tA6
DK2m(9/`3
/** +(>!nsf
* @param userService
5p9zl=mT
* The userService to set. 8<cD+Jtj
*/ g? 7%
publicvoid setUserService(UserService userService){ 7MX nt5qUh
this.userService = userService; /SLAg&
} e_Cns&
} HS1Gy/6'
;Od;q]G7L
a3o4> 9
x,kZ>^]&b
[X >sG)0S~
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, ] r8
hMv
" oWiQ{\IP
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 <28L\pdG`
}%j@%Ep[
么只需要: ,~;_-
java代码: P38D-fLq
JE~ci#|!
?NazfK
<?xml version="1.0"?> )ZkQWiP-
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ["'0vQ
M,0@@:
1.0//EN" "http://www.opensymphony.com/xwork/xwork- $@8$_g|Wz
Ift @/A
1.0.dtd"> WU}?8\?U%
\Qa6mt2h
<xwork> ^QX3p,Y
CuE>=y-"I
<package name="user" extends="webwork- _)4YxmK%
t?[|oz:v
interceptors"> [Tha
j
/.leY$
<!-- The default interceptor stack name 99T_y`df
nxzdg5A(w
--> C %l!"s^
<default-interceptor-ref KH4
5A'o
PA5_
name="myDefaultWebStack"/> O0?.$f9 s
|T53m;D
<action name="listUser" ],rtSUO
d',OQ,~{
class="com.adt.action.user.ListUser"> 9v7l@2/
<param *G{%]\s?
?t LJe
name="page.everyPage">10</param> h> K~<BAz'
<result IvLo&6swW
-Fcg}\9
name="success">/user/user_list.jsp</result> Y6(I
%hE`
</action> X2
{n&K
7%aaqQ1T
</package> eT??F
EC6)g;CO
</xwork> Lb# e
#&+0hS
{Mt4QA5iZ
;g[C=yhK`C
Qz*!jwg
H ]BH
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 Yh%a7K
\k?uh+xl
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。 wRwTN"Yg
y#\jc4F_a
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 $Iuf(J-5[
F<8Rr#Z
Ax[!7~s
1i;-mYGaMn
i?R+Ul`Q
我写的一个用于分页的类,用了泛型了,hoho L%,tc~)A
$+` YP
java代码: RhM]OJd'
oXA3i
|1d;0*HIgX
package com.intokr.util; v?b9TE
,o(7z^1Pe;
import java.util.List; ~RSOUrR
0i}4T:J@`
/** Pkx*1.uo
* 用于分页的类<br> hX#s3)87
* 可以用于传递查询的结果也可以用于传送查询的参数<br> J)O1)fR
* 3eUTV<!
* @version 0.01 _D9`L&X}
* @author cheng qx0RCP /s
*/ (yk^%
public class Paginator<E> { 7.4Q
privateint count = 0; // 总记录数 u|m>h(O
privateint p = 1; // 页编号 [n/'JeG5
privateint num = 20; // 每页的记录数 19od#
d3+
privateList<E> results = null; // 结果 $~UQKv>
AJ-p|[wPz
/** "kC uCc
* 结果总数 [jl'5l d
*/ Uf^zA/33
publicint getCount(){ oY@4G)5
return count; rM6^pzxe
} (g2?&b
iuz
p8<Y5:`
publicvoid setCount(int count){ $x&@!/&|pv
this.count = count; *@'4 A :A
} /H+br_D9
b#p)bcz!I
/** BXgAohg!
* 本结果所在的页码,从1开始 /E'c y
* h?wNmLre
* @return Returns the pageNo. ]=v_u9;
*/
Sbub|
publicint getP(){ #W#GI"K
return p; ;Ab`b1B
} *ayn<Vlh`^
mQt';|X@
/** $Xf1|!W%a%
* if(p<=0) p=1 6x KbK1W
* }>vf(9sF`
* @param p wD>tR
SW
*/ SX)giQLU
publicvoid setP(int p){ ;2"#X2B
if(p <= 0) A:Z$i5%'
p = 1; 3ThCY`
this.p = p; 7
}`c:u~j
} qJ QE|VM&
[Af&K22M(X
/** &wR