Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ~=h]r/b< U
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 r(h&=&T6
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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 J~eY,n.6]
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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 BF@(`D&>
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分页支持类: (f#QETiV
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java代码: ?BT\)@h
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package com.javaeye.common.util; Sj]k5(&
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import java.util.List; X&o!xV -+
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publicclass PaginationSupport { u*B.<GmN
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publicfinalstaticint PAGESIZE = 30; W{O:j
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privateint pageSize = PAGESIZE; 8>S"aHt 7
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privateList items; .281;] =
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privateint totalCount; #t:]a<3Y2
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privateint[] indexes = newint[0]; `*cT79
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privateint startIndex = 0; 9w'3d@
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public PaginationSupport(List items, int -fw0bL%0
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totalCount){ 4r;!b;3
setPageSize(PAGESIZE); }M'h5x
setTotalCount(totalCount); q$z#+2u
setItems(items); 3t22KY[`
setStartIndex(0); |7n&I`#
} .yE!,^j.gB
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public PaginationSupport(List items, int V#.;OtF]
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totalCount, int startIndex){ CnruaN@
setPageSize(PAGESIZE); ]y3V^W#
setTotalCount(totalCount); Yr@_X
setItems(items); N(>a-a
setStartIndex(startIndex); 6NH.!}"G9
} g66=3c9</6
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public PaginationSupport(List items, int f I>>w)5
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totalCount, int pageSize, int startIndex){ c|3%0=,`
setPageSize(pageSize); Hy5_iYP5
setTotalCount(totalCount); T0s7aw[zm
setItems(items); QLH&WF
setStartIndex(startIndex); []:;8fY
} Y,RED5]t
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publicList getItems(){ ?(Q" y\
return items; tt%Zwf
} q4{Pm $OW
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publicvoid setItems(List items){ F,Y,0f@4U9
this.items = items; VvN52
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} <$wh@$PK
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publicint getPageSize(){ "<ow;ciJF
return pageSize; In^MZ)?
} "}Kvx{L8
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publicvoid setPageSize(int pageSize){ i)f3\?,,
this.pageSize = pageSize; ]'V8{l
} )tR5JK} AV
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publicint getTotalCount(){ pg~vteq5
return totalCount; ?g%5 d
} /:v+:-lU
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publicvoid setTotalCount(int totalCount){ Q:eIq<erY
if(totalCount > 0){ H+vONg
this.totalCount = totalCount; 9 tkj:8_
int count = totalCount / &?>h#H222
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pageSize; O-Hu:KuIf
if(totalCount % pageSize > 0) I\DmVc\l
count++; T:o!H
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indexes = newint[count]; :zfnp,Gv
for(int i = 0; i < count; i++){ E0[!jZ:c
indexes = pageSize * kv&%$cA
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} -cs
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}else{ j*f%<`2`j
this.totalCount = 0; kB1]_v/
} :khl}|
} )V~Fl$A
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publicint[] getIndexes(){ j}XTa[
return indexes; Q1EY!AV8
} #%z--xuJL
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publicvoid setIndexes(int[] indexes){ 5r"BavA
this.indexes = indexes; u\=gps/Z
} !t "uNlN
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publicint getStartIndex(){ %AW5\ EX
return startIndex; KJWYG^zI
} 9+@"DuYc6
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publicvoid setStartIndex(int startIndex){ 75i
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if(totalCount <= 0) i@e.Uzn
this.startIndex = 0; /*p4(D_A
elseif(startIndex >= totalCount) d,[.=Jqv[
this.startIndex = indexes ^-{ 1]G:
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[indexes.length - 1]; 6G6Hg&B
elseif(startIndex < 0) nL!h hseH
this.startIndex = 0; RrKAgw
else{ a
OR}
this.startIndex = indexes aGVzg$
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[startIndex / pageSize]; A[J9v{bD
} 0CS^S1/[B`
} nV 38Mj2U
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publicint getNextIndex(){ :p@H
int nextIndex = getStartIndex() + MbLG8T:y
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pageSize; vLR)B@O,2
if(nextIndex >= totalCount) vE/g{~[5
return getStartIndex(); g0I<Fan
else zf$&+E-
return nextIndex; ;OQ-T+(T
} d='z^vHK
lz\{ X
publicint getPreviousIndex(){ *cCr0\Z`
int previousIndex = getStartIndex() - pC(AM=RY!
}<7Dyn,
pageSize; ,e+.Q#r*Y
if(previousIndex < 0) 'KpCPOhfR
return0; D *W+0
else dvxD{UH
return previousIndex; /-z_"G
} !_E E|#`n
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} wOE_2k
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抽象业务类 -aG( Yx
java代码:
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/** Noz+\O\
* Created on 2005-7-12 /'
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*/ [?Y u3E\
package com.javaeye.common.business; asP>(Li
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import java.io.Serializable; ]n?a h
import java.util.List; wJ!
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import org.hibernate.Criteria; RL~|Kr<7J
import org.hibernate.HibernateException; #W
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import org.hibernate.Session; [UNfft=K3P
import org.hibernate.criterion.DetachedCriteria; hDmtBdE
import org.hibernate.criterion.Projections; $>'}6?C.
import mhJ>5z
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org.springframework.orm.hibernate3.HibernateCallback; q9pBS1Ej
import #[sC H
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org.springframework.orm.hibernate3.support.HibernateDaoS ~U*2h =]
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upport; <9-tA\`8N
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import com.javaeye.common.util.PaginationSupport; m#,
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public abstract class AbstractManager extends g-mK(kY4p
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HibernateDaoSupport { RTA9CR)JP4
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privateboolean cacheQueries = false; !IoD";Oi
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privateString queryCacheRegion; [=e61Z
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publicvoid setCacheQueries(boolean ;knSn$
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cacheQueries){ [rTV)JsTb
this.cacheQueries = cacheQueries; i3: sV 5
} ~J)4 (411
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publicvoid setQueryCacheRegion(String 0VoC|,$U
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queryCacheRegion){ [KWF7GQi
this.queryCacheRegion = mfG|K@ODM-
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queryCacheRegion; <WaiJy?
} PZLW yp
] 5P{*
publicvoid save(finalObject entity){ 'BAe>r_Pn
getHibernateTemplate().save(entity); po=*%Zs*T
} >~BU<#
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publicvoid persist(finalObject entity){ K!|=)G3.`
getHibernateTemplate().save(entity); ehxtNjA
} Yc:b:\0}F6
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publicvoid update(finalObject entity){ <n }=zu
getHibernateTemplate().update(entity); ":]O3 D{r
} rorzxp{
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publicvoid delete(finalObject entity){ _?kf9 .
getHibernateTemplate().delete(entity); Tj0eW(<!s
} Zu%_kpW
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publicObject load(finalClass entity, _I{&5V~z
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finalSerializable id){ 4
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return getHibernateTemplate().load >z^T~@m7l
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(entity, id); !}1n?~]`
} 2"<}9A<Xs
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publicObject get(finalClass entity, KN}[N+V>
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finalSerializable id){ y
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return getHibernateTemplate().get G#dpSNV3|
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(entity, id); DVTzN(gO*~
} 4i~;Ql
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publicList findAll(finalClass entity){ J\;~(:
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return getHibernateTemplate().find("from M?nnpO
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" + entity.getName()); &`>*3m(
} l*X5<b9
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publicList findByNamedQuery(finalString OPKX&)SE-
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namedQuery){ +\:I3nKs%
return getHibernateTemplate N`iK1n4X
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().findByNamedQuery(namedQuery); X/7: *
} cK-!Evv
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publicList findByNamedQuery(finalString query, ?erDP8
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finalObject parameter){ ^f`#8G7 (
return getHibernateTemplate Rdnd|
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().findByNamedQuery(query, parameter); IZ2#jSDn
} U_VD* F4Bv
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publicList findByNamedQuery(finalString query, TfZO0GL$
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finalObject[] parameters){ DJn>. Gd
return getHibernateTemplate V 9<[v?.\
7#g C(&\A
().findByNamedQuery(query, parameters); F`u{'w:Hv
} yv'rJI~ Ps
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publicList find(finalString query){ ;<&s_C3
return getHibernateTemplate().find Tu6he8Q-
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(query); ?` `+OH
} OOk53~2id
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publicList find(finalString query, finalObject D 'u+3
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parameter){ Hb]7>[L
return getHibernateTemplate().find kb%W3c9HO
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(query, parameter); 8F[j}.8q
} VX>_Sps
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public PaginationSupport findPageByCriteria vuAAaKz
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(final DetachedCriteria detachedCriteria){ P&F)E#Sa
return findPageByCriteria N%?o-IY
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); d3{Zhn@
} be764do
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public PaginationSupport findPageByCriteria 3p^WTQ>(
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(final DetachedCriteria detachedCriteria, finalint 4\$Ze0tv
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startIndex){ $PTedJ}*Y
return findPageByCriteria 7H[+iS0
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(detachedCriteria, PaginationSupport.PAGESIZE,
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startIndex); S"eKiS,z
} >`NM?KP s
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public PaginationSupport findPageByCriteria m+u>%Ys`
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(final DetachedCriteria detachedCriteria, finalint vEgJmHv;
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pageSize, J-QQ!qa0
finalint startIndex){ e6_.ID'3
return(PaginationSupport) 2;&13%@!
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getHibernateTemplate().execute(new HibernateCallback(){ oqY?#p/
publicObject doInHibernate Xoik%T-
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(Session session)throws HibernateException { Q3/q%#q>
Criteria criteria = 9M!_D?+P?
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detachedCriteria.getExecutableCriteria(session); ~/#?OLj(T
int totalCount = qB=pp!zQ
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((Integer) criteria.setProjection(Projections.rowCount K9P"ncMt
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()).uniqueResult()).intValue(); -s)2b
;
criteria.setProjection Zk/NO^1b
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(null); H\b5]q%
List items = zHU#Jjc_b
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criteria.setFirstResult(startIndex).setMaxResults woT" 9_tN
3@&H)fdp6a
(pageSize).list(); 6d.m@T6~
PaginationSupport ps = pvM8PlYo]`
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new PaginationSupport(items, totalCount, pageSize, ~d%Q1F*,=
,,Db:4qfjD
startIndex); U'lD|R,g
return ps; ,yqzk.
} 0F3>kp4u
}, true); HcVPJuD
} I{AU,
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public List findAllByCriteria(final C>u 3n^
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DetachedCriteria detachedCriteria){ ljis3{kn""
return(List) getHibernateTemplate bOFLI#p&
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().execute(new HibernateCallback(){ eHJ7L8#
publicObject doInHibernate sogbD9Jc
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(Session session)throws HibernateException { 2%<jYm#'z-
Criteria criteria = }?~uAU-
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detachedCriteria.getExecutableCriteria(session); :aqh8bv
return criteria.list(); \|pAn
} T7T!v
}, true); }ri*e2y)
} 2at?9{b
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public int getCountByCriteria(final WV @Tm$r
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DetachedCriteria detachedCriteria){ Y-Ku2m
Integer count = (Integer) _l,Z38
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getHibernateTemplate().execute(new HibernateCallback(){ E5t+;vL~
publicObject doInHibernate 1;xw)65
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(Session session)throws HibernateException { 9e)+<H
Criteria criteria = d-<y'GYw
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detachedCriteria.getExecutableCriteria(session); (XwLKkw0n
return uy9B8&Sr
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criteria.setProjection(Projections.rowCount )e2IT*7
`p{!5
()).uniqueResult(); h]MVFn{
} -5cH$]1\
}, true); cMWO_$
return count.intValue(); #rpqt{ml
} eq+o_R}CS
} }J?fJ(
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用户在web层构造查询条件detachedCriteria,和可选的 ,?`1ve_K<
u#M)i30j
startIndex,调用业务bean的相应findByCriteria方法,返回一个 $.N~AA~0
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PaginationSupport的实例ps。 :ky<`Jfr`
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ps.getItems()得到已分页好的结果集 Tb={g;0@
ps.getIndexes()得到分页索引的数组 M96( Rg
ps.getTotalCount()得到总结果数 V0 F30rK
ps.getStartIndex()当前分页索引 _o?(t\B9{
ps.getNextIndex()下一页索引 c9uT`h
ps.getPreviousIndex()上一页索引 !~N4}!X3du
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 T{<@MK%],d
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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 E.`dk.
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一下代码重构了。 !ix<|F5
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我把原本我的做法也提供出来供大家讨论吧: p}A4K#G
dT)KvqX
首先,为了实现分页查询,我封装了一个Page类: k<| l\]w
java代码: D w=Z_+J
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/*Created on 2005-4-14*/ 8}{o2r@
package org.flyware.util.page; d `kM0C
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/** vNt>ESPB
* @author Joa =_=Z;#`cXk
* b_jZL'en
*/ eqZ+no
publicclass Page { &U~r}=
!Gp3/<"Wy$
/** imply if the page has previous page */ _`_IUuj$E
privateboolean hasPrePage; !e'0jf-~
O_Rcd&<mr
/** imply if the page has next page */ U[QD!
privateboolean hasNextPage; aoDD&JE
E^ok`wfO
/** the number of every page */ 8RAeJ~e
privateint everyPage; r^A#[-VyNP
*fl{Y(_OO
/** the total page number */ Yb\\
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privateint totalPage; iEpq*Qj
;:4P'FWm^
/** the number of current page */ 'K3s4x($
privateint currentPage; =*g$#l4
l}0V+
/** the begin index of the records by the current l-S'ATZ0p
}utNZhJ
query */ V`\f+Uu
privateint beginIndex; 9*|3E"Vr
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|
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/** The default constructor */ }11`98>B6:
public Page(){ %i&/$0.8
^+as\
} tw/#ENo
:5S |x/
/** construct the page by everyPage x$n~f:1Y
* @param everyPage 7<:Wq=e!r
* */ 3_MS'&M
public Page(int everyPage){ V[Rrst0yo
this.everyPage = everyPage; +lW}ixt
} adI!W-/R:
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/** The whole constructor */ qo6LC >Qg
public Page(boolean hasPrePage, boolean hasNextPage, >&;>PZBPCO
TH>?Gi)"
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int everyPage, int totalPage, V5O=iMP
int currentPage, int beginIndex){ ySQ-!fQnP
this.hasPrePage = hasPrePage; fJWxJSdi
this.hasNextPage = hasNextPage; rg5]`-!=
this.everyPage = everyPage; R3j#WgltP
this.totalPage = totalPage; m-ph}
this.currentPage = currentPage; {^cF(7p
this.beginIndex = beginIndex; vx!::V7s6
} WQ[}&kY~
+_X,uvR
/** #Pu@Wx
* @return AU)1vx(\w
* Returns the beginIndex. %{7_E*I@n
*/ FgWkcV6B
publicint getBeginIndex(){ 0+}EA[
return beginIndex; KQ4kZN
} Pr5g6I'G
" ^HK@$
/** ]$~Fzs
* @param beginIndex >gk z4.*
* The beginIndex to set. dG\U)WA(p
*/ ]<kupaRQ
publicvoid setBeginIndex(int beginIndex){ S jVsF1d_
this.beginIndex = beginIndex; X,TTM,1w
} _[OF"X2
U{uPt*GUd/
/** u C,"5C
* @return ]C16y.
~e
* Returns the currentPage. ;&Bna#~B
*/ ]V36-%^
publicint getCurrentPage(){ ><NI'q*cQ
return currentPage; t7w-TJvP
} ~u /aOd
q=6Cc9FN
/** yo\N[h7
* @param currentPage EBoGJ_l
* The currentPage to set. ic*->-!
*/ ~;M)qR?]W
publicvoid setCurrentPage(int currentPage){ gjj 93
this.currentPage = currentPage; D|@bGN
} T'ED$}N>~
0xJ7M.
/** /?KtXV>]
* @return D##+)`dK
* Returns the everyPage. 2+?T66 g
*/ sm 's-gD
publicint getEveryPage(){ G2.|fp_}pG
return everyPage; pheE^jUr
} GE1i+.+-.
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/** -S"5{ N73
* @param everyPage X E|B)Q(
* The everyPage to set. ZgV~W#t
*/ &v^!y=Bt
publicvoid setEveryPage(int everyPage){ yND"bF9
this.everyPage = everyPage; I2f?xJ2/Z
} 25 CZmsg
x_*%*H
/** ^SZw`]
* @return *~p(GC
* Returns the hasNextPage. !^m%O0DT
*/ B:4Ka]{YO
publicboolean getHasNextPage(){ I@2 uF-
return hasNextPage; &
_; y.!
} 2w+U$6e C
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/** L7'%;?Z
* @param hasNextPage #/Ruz'H1>
* The hasNextPage to set. vr=~M?
*/ lT2 4JhJ#
publicvoid setHasNextPage(boolean hasNextPage){ A)tP()+)
this.hasNextPage = hasNextPage; w|IjQ1{
} ! Tx&vtq
TZ[Zm
/** bS.s?a
* @return 33Jd!orXU
* Returns the hasPrePage. Cyq?5\ a
*/ &FSmqE;@^
publicboolean getHasPrePage(){ "~F3*lk#E
return hasPrePage; <5S@ORN
} {;s;.
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/** K]c4"JJ
* @param hasPrePage kb71q:[
* The hasPrePage to set. j^flwk
*/ :\XI0E
publicvoid setHasPrePage(boolean hasPrePage){ ~#R9i^Y
this.hasPrePage = hasPrePage; 'JieIKu
} C|MQ
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,~COZi;R.D
/** rcV-_+KE(B
* @return Returns the totalPage. $9 +YNgW>
* &-%>qB|*
*/ 1B|8ZmFJj
publicint getTotalPage(){ Z$p0&~
return totalPage; bB!#:j>(v
} `K*b?:0lp
B
z^|SkEit
/** q2hFOm
* @param totalPage %SrM|&[
* The totalPage to set. j9d!yW
*/ >I}9LyZt
publicvoid setTotalPage(int totalPage){ {:Aw_z:'
this.totalPage = totalPage; ;}qhc l+
} `lO(s%HC
=<c#owe:m
} Xa," 'r
~. YWV
O~!T3APGU
X&M4MuL
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M
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 K=dR%c(
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个PageUtil,负责对Page对象进行构造: Qck|#tc
java代码: u7fK1 ^O
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/*Created on 2005-4-14*/ "5C`,4s
package org.flyware.util.page; ?-MP_9!JK
qH>`}/,P
import org.apache.commons.logging.Log; eujK4s
import org.apache.commons.logging.LogFactory; hA}~es=c
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/** %ft &Q
* @author Joa eg/<[ A:
* r@U3sO#N
*/ %c|UmKKi
publicclass PageUtil { b0v:12q
;{#^MD MB
privatestaticfinal Log logger = LogFactory.getLog /J3ZL[o?Q
r X'*|]
(PageUtil.class); JTU#vq:TY
v>Lm;q(
/** qJPT%r
* Use the origin page to create a new page YO+{,$
* @param page ~YP Jez
* @param totalRecords X(A.X:"
* @return S0d~.ah30
*/ d>0+A)6>
publicstatic Page createPage(Page page, int K4Sk+
v
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totalRecords){ $P z`$~
return createPage(page.getEveryPage(), ,CvG 20>
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page.getCurrentPage(), totalRecords); 'sh~,+g
} j}1zdA
mYxyWB
/** dq\FBwfe
* the basic page utils not including exception 6at1bQ$
NTo!'p:s
handler vb
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* @param everyPage 6e,xDr
* @param currentPage .IarkeCtb
* @param totalRecords Fmyj*)J[Z
* @return page O`G/=/GZ
*/ =,y |00l
publicstatic Page createPage(int everyPage, int 80b;I|-T,
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currentPage, int totalRecords){ 6%,C_7j
everyPage = getEveryPage(everyPage); ~y HU^5D
currentPage = getCurrentPage(currentPage); DdQ;Q5|
int beginIndex = getBeginIndex(everyPage, r]@0eb
(*p ,T
currentPage); ]rehW}
int totalPage = getTotalPage(everyPage, sRSz}]
o*WY=
totalRecords); =Prb'8 W
boolean hasNextPage = hasNextPage(currentPage, : _e#
Byl^?5
totalPage); ?BA]7M(,4
boolean hasPrePage = hasPrePage(currentPage); bmgn cwlz
$+JS&k/'m
returnnew Page(hasPrePage, hasNextPage, U>Ld~cw
everyPage, totalPage, K6/@]y%Wr
currentPage, r3E!dTDWq
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beginIndex); /1N6X.Zb
} uvDzKMw~R
; Uc0o!1
privatestaticint getEveryPage(int everyPage){ qgIb/6;xQ
return everyPage == 0 ? 10 : everyPage; +gd4\ZG
} r={c,i
ho8`sh>N
privatestaticint getCurrentPage(int currentPage){ z]B]QB
Y[
return currentPage == 0 ? 1 : currentPage; f()FY<b
}
$`ZzvZ'r
K 0gI):
privatestaticint getBeginIndex(int everyPage, int z>sbr<doa
@NhvnfZ
currentPage){ 6E(Qx~iL
return(currentPage - 1) * everyPage; Y8M]Lwj
} }En
,}oM-B
privatestaticint getTotalPage(int everyPage, int qm/Q65>E
:NJ_n6E
totalRecords){ pl@O
N"=[
int totalPage = 0; 2M#M"LHo
Q!-
0xlx
if(totalRecords % everyPage == 0) P-F)%T[
totalPage = totalRecords / everyPage; W} WI; cI
else A.<H>=Z#O
totalPage = totalRecords / everyPage + 1 ; H]Hv;fcC
fjvN$NgVs
return totalPage; \(226^|j
} Grs]d-xI
mxor1P#|
privatestaticboolean hasPrePage(int currentPage){ x{D yTtX<
return currentPage == 1 ? false : true; QaUm1i#
} +uay(3m((
S$KFf=0
privatestaticboolean hasNextPage(int currentPage, DPi_O{W>
J+rCxn?;g
int totalPage){ V5+SWXZ
return currentPage == totalPage || totalPage == HhO".GA
A-:O`RK
0 ? false : true; %ZHP2j
%~
} o FjIA!
;&H4u)
z/i+EE
} DN4$Jva
r0p w_j
YK|bXSA[
[MuEoWrq(}
),%6V5a+E
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。 wFG3KzEq ~
*s@Qtgu
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 U
qG
.:@T
{vAE:W.s
做法如下: V_plq6z
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 + QQS={
06jqQ-_`h
的信息,和一个结果集List: Aw&tP[N[
java代码: *#TUGfwy
.<kqJ|SVi
KNH1#30 K
/*Created on 2005-6-13*/ v<Bynd-
package com.adt.bo; ECv)v
l5L.5$N
import java.util.List; E=){K
<uj8lctmP
import org.flyware.util.page.Page; pp9Zb.D\
mPq$?gdp
/** wAnb
Di{W
* @author Joa !w&kyW?e
*/ 2^?:&1:
publicclass Result { >X*Mio8P#
sz9L8f2
private Page page; CI3XzH\IX*
`/Y{ l
private List content;
yf&7P;A
<&)v~-&O
/** ?%H):r
* The default constructor Y@PI {;!
*/ /x3/Ubmz~x
public Result(){ {Zp\^/
super(); asJ)4ema
} L(X6-M:
KK@.~'d
/** ZvcJK4hi
* The constructor using fields g-Pwp[!qkf
* b!M"VDjQ
* @param page Nj("|`9"
* @param content fu~+8CE.
*/ Bn>8&w/P
public Result(Page page, List content){ `a9L%z
this.page = page; ZE%YXG
this.content = content; =]k {"?j
} b(9FZ]7S
>I=2!C1w
/** ZJlEKib%2
* @return Returns the content. z0/}
!
*/ Wb S4pdA
publicList getContent(){ >[X{LI(_<<
return content; 6~*9;!th
} 4DTzSy:x
G7D2{J{1
/** ;E'"Ks[GH
* @return Returns the page. [Y`,qB<B
*/ 9{:O{nl
public Page getPage(){ eI@
q|"U
return page; ,^S@EDq
} !0N7^Z"gtz
37;$-cFE
/** ?&Pg2]g<
* @param content *cyeO*
* The content to set. a
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*/ @)K%2Y`
public void setContent(List content){ u[{tb
this.content = content; Ld B($4,
} 3"rzb]=R
x\QY@9
/** wY"Q o7
* @param page 7.j[a*^
* The page to set. .; )l
*/ 29reG,>
publicvoid setPage(Page page){ Q[#vTB$f
this.page = page; KM`eIw>8
} }2ZsHM^]%
} Oh4AsOj@
`c'W-O/
X6^},C'E.:
`%j~|i)4
!~h}8'a?
2. 编写业务逻辑接口,并实现它(UserManager, Q);n<Z:X~
GIAc?;zY
UserManagerImpl) BATG FS&
java代码: E#s)52z=B
=~+DUMBT
bMU(?hb
/*Created on 2005-7-15*/ 9aJ%`i
package com.adt.service; N~F
RM& x
Zk[&IBE_
import net.sf.hibernate.HibernateException; JH8zF{?
2}W0
F2*
import org.flyware.util.page.Page; YZ+RWu9K
#0Tq=:AE>
import com.adt.bo.Result; Bphof0{<}
cm[c ze+*
/** SRSvot};C
* @author Joa 57 #6yXQ
*/ sCu+Lg~f
publicinterface UserManager { aj}(E+
1@lJonlF
public Result listUser(Page page)throws |`jjHuQ;
Zy09L}5 9P
HibernateException; r/*=%~*
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} rLX4jT^
YTw#JOO
j+HHQd7Y
L;od6<.*m
@&}q}D
java代码: Vi$-Bw$@
(<
=}]v
07hF2[i
/*Created on 2005-7-15*/ ~ Uo)0
package com.adt.service.impl; ]TaN{"
72,rFYvpK
import java.util.List; EKp@9\XBC
\.g\Zib )
import net.sf.hibernate.HibernateException; @UdfAyL
lqb/eN9(t
import org.flyware.util.page.Page; IVW1]y
import org.flyware.util.page.PageUtil; i.:. Y
w/L `
import com.adt.bo.Result; TFcT3]R[rL
import com.adt.dao.UserDAO; _$>pw<
import com.adt.exception.ObjectNotFoundException; yOvm`9
import com.adt.service.UserManager; )+Oujt
nB] >!q
/** CNww`PX,zZ
* @author Joa Ig5L$bAM~
*/ |{@FMxn|q
publicclass UserManagerImpl implements UserManager { B*gdgM*`
O=9-Qv|
private UserDAO userDAO; %K]euEqs
CpQN,-4
/** $m CarFV-T
* @param userDAO The userDAO to set. 4BwQA#zE
*/ w eQYQrN
publicvoid setUserDAO(UserDAO userDAO){ MJ=)v]a
this.userDAO = userDAO; WlYs~(=9
} P<fnLQ9
Q%-di=
/* (non-Javadoc) R-:fd!3oQ
* @see com.adt.service.UserManager#listUser ,E.' o=Z
]
7 _`]7p
(org.flyware.util.page.Page) M,5"b+mX[~
*/ sZLT<6_B
public Result listUser(Page page)throws ?,yj")+
i{I~mrm/'\
HibernateException, ObjectNotFoundException { VS&TA>
int totalRecords = userDAO.getUserCount(); b^[F""!e
if(totalRecords == 0) [2|kl
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throw new ObjectNotFoundException /W<>G7%.
eu|j=mB
("userNotExist"); 4hw@yTUo
page = PageUtil.createPage(page, totalRecords); A0%}v*
List users = userDAO.getUserByPage(page); +,2Jzl'-
returnnew Result(page, users); $TI5vhQ
} RQFI'@Ks
+<prgP`v
} ;us%/kOR
",)Qc!^P$
jV8q)=}*)
hkOsm6
jP~Z`yf
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 rS1fK1dys
P4T h_B7
询,接下来编写UserDAO的代码: 1@gg uRF:
3. UserDAO 和 UserDAOImpl: S(mF%WJ
java代码: {hJXj,
M?/jkc.8H
zB?
V_aT
/*Created on 2005-7-15*/ 0cT*z(
package com.adt.dao; ,hVvve,j}
3<F </
import java.util.List; )(7&X45,k
<40rYr$/J
import org.flyware.util.page.Page;
+D1 d=4
7n90f2"m
import net.sf.hibernate.HibernateException; fo4.JyBk
4 QZ?}iz
/** -rKO
)}
* @author Joa ^V|Oxp'7_
*/ ;=? ~
-_
publicinterface UserDAO extends BaseDAO { oBUxKisW
pMs
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publicList getUserByName(String name)throws 2r%lA\,h$
/CTc7.OYt
HibernateException; xF8}:z0
r",]Voibd
publicint getUserCount()throws HibernateException; c/5W4_J
xm6 EKp:
publicList getUserByPage(Page page)throws X w .p
iV fgDo
HibernateException; L}m8AAkP[
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} >{ me
+
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X{kpSA~
KFZm`,+69
6{qIU}!
java代码: +-B^Z On
6:%
L![FX
JH7Ad (:
/*Created on 2005-7-15*/ 2Dd|~{%
package com.adt.dao.impl; <[GYLN[0Q
L>Mpi$L
import java.util.List; C%~a`e|/Y
wZh:F
!
import org.flyware.util.page.Page; [Ei1~n)o
DKVT(#@T
import net.sf.hibernate.HibernateException; Ys8SDlMo
import net.sf.hibernate.Query; *z'yk*
V]S1X^
import com.adt.dao.UserDAO; OMk5{-8B
0[<~?`:)
/** 5b/ojr7
* @author Joa 8_K60eXz
*/ +wW@'X
public class UserDAOImpl extends BaseDAOHibernateImpl U}$DhA"r"
4'p=p#o
implements UserDAO { >]=j'+]
*;|`E(
/* (non-Javadoc) MuBx#M/
* @see com.adt.dao.UserDAO#getUserByName ouHu8)q'r
_73h<|0
(java.lang.String) `c+/q2M
*/ { BEo &
publicList getUserByName(String name)throws iBudmT8
gN {'UDg
HibernateException {
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String querySentence = "FROM user in class d1joVUYE
#Dfo#]k(
com.adt.po.User WHERE user.name=:name"; vEQ<A<[Z
Query query = getSession().createQuery gw _$
vB!|\eJ
(querySentence); _ q(Q
query.setParameter("name", name); )IT6vU"-yd
return query.list(); &:=$wc
}
,YhwpkL
, %YBG1E[y
/* (non-Javadoc) #%@MGrsK
* @see com.adt.dao.UserDAO#getUserCount() u-"c0@
*/ dGwszziuK
publicint getUserCount()throws HibernateException { ]S 7^ITn
int count = 0; 0J~Qq]g
String querySentence = "SELECT count(*) FROM FEz>[#eOX
UofTll)
user in class com.adt.po.User"; ^zEE6i
Query query = getSession().createQuery 7~M<cD
eo^/c+FG
(querySentence); $j)hNWI
count = ((Integer)query.iterate().next oPKXZU(c
-RJE6~>'\
()).intValue(); &Np9kIMCB
return count; @/%{15s.
} %i)B*9k
buk=p-oi
/* (non-Javadoc) 8&V_$+ U
* @see com.adt.dao.UserDAO#getUserByPage x|eeRf|
s~26
(org.flyware.util.page.Page) +CM7C%U
*/ Lv1{k\aw
publicList getUserByPage(Page page)throws d77r9
-v?hqWMp#
HibernateException { 7t-Lz|
$"
String querySentence = "FROM user in class }%{MPqg
{F|48P;J
com.adt.po.User"; .I$}KE)
Query query = getSession().createQuery ^;F{)bmu+)
;HOPABWz)
(querySentence); G[idN3+#
query.setFirstResult(page.getBeginIndex()) .]Mn^2#j
.setMaxResults(page.getEveryPage()); 7.bN99{xPM
return query.list(); v[<Bjs\q5
} u}6v?!
^+?|Qfi
} !p
8psi0
;LJ3c7$@lf
t^EhE
#G3N(wV3
6Gn4asoA
至此,一个完整的分页程序完成。前台的只需要调用 > 7`&0?
f"&Xr!b.h
userManager.listUser(page)即可得到一个Page对象和结果集对象 #k5#j4!b
}fhHXGK.
的综合体,而传入的参数page对象则可以由前台传入,如果用 0'$p$K
3}&ZOO
webwork,甚至可以直接在配置文件中指定。 #p
yim_
!d9AG|
下面给出一个webwork调用示例: 9>,Qgp,w
java代码: K^%-NyV
&d`^E6#
m(sXk}e;1
/*Created on 2005-6-17*/ N~,_`=yRx
package com.adt.action.user; <M[U#Q~?~e
$M"0BZQ?y!
import java.util.List; O2-M1sd$
MmU%%2QG
import org.apache.commons.logging.Log; 6!EYrX}rI[
import org.apache.commons.logging.LogFactory; <8(?7QI
import org.flyware.util.page.Page; (&&87(
: cp
import com.adt.bo.Result; w\|Ei(
import com.adt.service.UserService; i~qfGl p6)
import com.opensymphony.xwork.Action; .6T6 S
v
2Eh@e([PMs
/** qg,Nb
* @author Joa zXc}W*ymj
*/ xQt 3[(Z
publicclass ListUser implementsAction{ k ~6-cx
?)tK!'
privatestaticfinal Log logger = LogFactory.getLog E1>/R
m[2'd
(ListUser.class); :X .,
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private UserService userService; 2f:Mm'XdB
0|)19LR
private Page page; oJaAM|7uv
V"d=.Hb>
privateList users; Pl~P- n
&+nRIv S_`
/* J l7z|Q S
* (non-Javadoc) H)JS0
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* =L0fZf
* @see com.opensymphony.xwork.Action#execute() fU*C/ d3
*/ ,9/5T: 2
publicString execute()throwsException{ Ex($
Result result = userService.listUser(page); 6GOcI#C9C
page = result.getPage(); V;9 }7mw
users = result.getContent(); Ht=$] Px
return SUCCESS; J^H=i)A
} IKf`[_,t]
)bWrd$X
/** O<,r>b,
* @return Returns the page. ,@Z_{,b
*/ a20w,
public Page getPage(){ 4'At.<]jL
return page; LR$z0rDEM
} E5x]zXy4
.1ddv4Hk
/** ,hE/II`-d'
* @return Returns the users. *)PG-$6X&
*/ $N.`)S<
publicList getUsers(){ E#h~V5Tf
return users; .Dv=pB,u
} 3&J&^O
VJ1*|r,
/** q`loOm=y
* @param page :Ee ?K
* The page to set. ],?pe
*/ .98.G4J>
publicvoid setPage(Page page){ ul}'{|4
this.page = page; q,,j',8kq/
} tyXl}$)y
dF2@q@\.+
/** G\mKCaI8
* @param users iB{xvyR
* The users to set. mmN|F$;r
*/ $HRed|*.C
publicvoid setUsers(List users){ )q(:eoLDm
this.users = users; (@?eLJlT
} U?6yke
<$C<Ba?;?
/** !1-&Y'+
* @param userService V
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* The userService to set. FU]4oKx
*/ 9 }n,@@
publicvoid setUserService(UserService userService){ W8.j/K:
this.userService = userService; /W9
&Ke
} 4I.1D2 1jA
} -h9#G{2W[
83?1<v0%
X<K9L7/*
0 0,9azs
5&|5 a} 8
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, NTVHnSoHh
lu3.KOD/
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 V* Qe5j9
|J?:91
么只需要: ruHrv"29
java代码: .WO/=#O
'{^8_k\}B
5\?3$<1I
<?xml version="1.0"?> g$gS7!u,
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ^teaJ y%
k1wr/G'H[
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 9i[4"&K
fn?VNZ`J
1.0.dtd"> Okoo(dfM
X4
Y
<xwork> $/.<z(F
zg7G^!PU
<package name="user" extends="webwork- NY 4C@@"
zze z~bv7:
interceptors"> {0fz9"|U
=?+w)(*0c
<!-- The default interceptor stack name xtsL8-u f
4[(?L{
--> Lv3XYZgW~
<default-interceptor-ref :B+Rg cqi
Q4CJ]J`
name="myDefaultWebStack"/> R%W@~o\p]
OT%V{hD
<action name="listUser" yI:r7=KO
6mAB(X^+
class="com.adt.action.user.ListUser"> [lOf|^9
<param |I/,F;'
Dx0O'uwR
name="page.everyPage">10</param> - &NQ\W
<result !3QRzkJX~
'FqEB]gu
name="success">/user/user_list.jsp</result> km}MqBQl
</action> fK);!Hh
w=5
</package> 4y1>
e|~C?Ow'J
</xwork> QK'`=MU
"]w!`^'_
?Oqzd$-
0 S2v"(_T
>KKeV(Ur
)]tvwEo
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 {Evcc+Eq
>6k}HrS1V
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。 "'~|}x1Uv
quY "
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 HIsB|
~JAjr(G#o
/=q.tDH=I
]79~:m[C
P6:;Y5e0
我写的一个用于分页的类,用了泛型了,hoho :b<KX%g
xl3zy~;M
java代码: D {Oq\*
q[Vi[b^F
8s~\iuk
package com.intokr.util; Q%I#{+OT
hR!}u}ECd
import java.util.List; \hrrPPD1z
g;l'VA3v
/** "bPCOJ[v9
* 用于分页的类<br> XzW7eO,A
* 可以用于传递查询的结果也可以用于传送查询的参数<br> .uBO
* =?HzNA$yh
* @version 0.01 &;Ed*OJ
* @author cheng Oy:QkV9
*/ TR~|c|B
public class Paginator<E> { u0s'6=
privateint count = 0; // 总记录数 zuk"
privateint p = 1; // 页编号 cxY$LY!zX
privateint num = 20; // 每页的记录数 {s,^b|I2#U
privateList<E> results = null; // 结果 #UBB
lE#
Xthtw *
/** {x7=;-
* 结果总数 qw5&Y$((
*/ W=UqX{-j)
publicint getCount(){ :4%<Rp
return count; phr2X*Z/)Y
} ujiZM
&{ DR6
publicvoid setCount(int count){ 1;aF5~&
this.count = count; ;i.I&*t
} *}>Bkq9h
lxo.,n)
/** .\Ul!&y
* 本结果所在的页码,从1开始 c6t2Q6zV
* >6OCKl
* @return Returns the pageNo. sTt9'P`
*/ |3 ;u"&(P
publicint getP(){ ,.[.SU#V
return p; P`p6J8}4
} bo&\3
{,i=>%X*
/** `b#/[3
* if(p<=0) p=1 sS-W~u|C
* /%62X{=>;
* @param p a#^_"GX
*/ *e%Dg{_
publicvoid setP(int p){ kNRyOUy
if(p <= 0) 'G<}U343=8
p = 1; >~h>#{&
this.p = p; L^3~gM"!
} 3b+7^0frY#
l8er$8S}
/** 8oa)qaG1
* 每页记录数量 ZyHIMo|
*/ /.7$`d
publicint getNum(){ ,c@r`
x
return num; s`;0
t YG
} Lwp-2`%
Hr
/W6C
/** #!w:_T%
* if(num<1) num=1 {An8/"bv}
*/ lr`?yn1D(
publicvoid setNum(int num){ r4 9UJE
if(num < 1) ?68$3;
num = 1; Sc% aJ1
this.num = num; /z/hUa
} *Hxj_
\nC5 ,Rz
/** uFGv%W
* 获得总页数 ?UxG/]",
*/ BO8%:/37[4
publicint getPageNum(){ cC b>zI
return(count - 1) / num + 1; ^Yf3"D?&
} w/qQ(]n8
uG2Xkj
/** ARmu{cL
* 获得本页的开始编号,为 (p-1)*num+1 BXT80a\
*/ Y*`:M(
publicint getStart(){ nsZDZ/jx
return(p - 1) * num + 1; 8dr0 DF$c
} W3Fy mCI
F"-S~I7'L
/**
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* @return Returns the results. $/4Wod*l
*/ yonJd
publicList<E> getResults(){ "CIpo/ebL
return results; `DI{wqV9
} u86J.K1Q
g ^D)x[
public void setResults(List<E> results){ ;~}-AI-
this.results = results; }9MW!Ss
} Z|]l"W*w
\B*k_W/r@
public String toString(){ #rh0r`
StringBuilder buff = new StringBuilder '}wG"0
vs5
D:cZ}
(); {KW&wsI
buff.append("{"); 6$W -?
buff.append("count:").append(count); :`{9x%o;
buff.append(",p:").append(p); *raIV]W3
buff.append(",nump:").append(num); fGu5%T,
buff.append(",results:").append 6&i[g
K~7'@\2
?
(results); Q.j-C}a
buff.append("}"); 3m-edpH
return buff.toString(); 1h#w"4
} I'KR'1z 9
R=2
gtW"r
} +}Qv6s#
E`oSi
ez)
ZkJY.H-F