Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 y%Rq6P=4Q
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 R_W6}
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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 CY~ S{w
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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 D*&#}c,*
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。 !mZDukfjQ
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分页支持类: QUeuN?3X\
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java代码: ZyM7)!+kPa
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package com.javaeye.common.util; A!cY!aQ
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import java.util.List; p$=Z0p4%LL
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publicclass PaginationSupport { VBUrtx:
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publicfinalstaticint PAGESIZE = 30; \sz*M
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privateint pageSize = PAGESIZE; .Hnhd/ c
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privateList items; dbJ3E)rF
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privateint totalCount; 4VF4 8
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privateint[] indexes = newint[0]; e"y-A&|
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privateint startIndex = 0; IClw3^\l
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public PaginationSupport(List items, int 7Kf
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totalCount){ >AFQm
setPageSize(PAGESIZE); <Drm#2x!E
setTotalCount(totalCount); yg.o?eML
setItems(items); m%0_fNSJ
setStartIndex(0); Na$.VT
} =r4sF!g
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public PaginationSupport(List items, int NH;e|8
f&j\gYWq
totalCount, int startIndex){ A9lw^.
setPageSize(PAGESIZE); eC"k-a8j+
setTotalCount(totalCount); up{0ehr
setItems(items); 4E2#krE%
setStartIndex(startIndex); {#st>%i
} jzJQ/ZFS
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public PaginationSupport(List items, int n}b{u@$
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totalCount, int pageSize, int startIndex){ _aYhW{wW
setPageSize(pageSize); 0SU v 5c
setTotalCount(totalCount); p>,D F9W`
setItems(items); |sI@m@
setStartIndex(startIndex); 0BNH~,0u
} wmww7
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publicList getItems(){ 8 :WN@
return items; w$IUm_~waa
} 4#{f8
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publicvoid setItems(List items){ Qo:vAv
this.items = items; V~VUl)
} ;vneeW4|
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publicint getPageSize(){ WH4rZ }Z`
return pageSize; @<3E`j'p
} DXG`% <ZMn
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publicvoid setPageSize(int pageSize){ pV(k6h
this.pageSize = pageSize; Z^]jy>dj
} c(uDkX
}W@refS
publicint getTotalCount(){ #8sy QWlG
return totalCount; =@
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} -<g[P_#
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publicvoid setTotalCount(int totalCount){ e/cHH34
if(totalCount > 0){ rrR"2WuGO
this.totalCount = totalCount; <o9AjASv\,
int count = totalCount / $@@ii+W}\
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pageSize; 'j*Q
if(totalCount % pageSize > 0) qH0JZdk
count++; %X's/;(Lx`
indexes = newint[count]; sBYDo{01
for(int i = 0; i < count; i++){ JN:L%If
indexes = pageSize * ^\g.iuE
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i; 6/#+#T
} '%4fQ%ID}
}else{ W**[:n+
this.totalCount = 0; *+zFsu4l
} w,X)g{^T
} SHs [te[
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publicint[] getIndexes(){ g%tUk M
return indexes; z:Tj0<A'
} n-2!<`UFX
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publicvoid setIndexes(int[] indexes){ tvf5b8(Y-
this.indexes = indexes; ?FNgJx*\S
} b1>]?.
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publicint getStartIndex(){ w_o+;B|I
return startIndex; bl&9O
} .?rs5[th*
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publicvoid setStartIndex(int startIndex){ 0<:rp]<,
if(totalCount <= 0) }cI-]|)|2
this.startIndex = 0; vs$h&o>|
elseif(startIndex >= totalCount) qLN\>Z,3;
this.startIndex = indexes h^_^)P+;
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[indexes.length - 1]; Iila|,cM
elseif(startIndex < 0) GApvRR+Z
this.startIndex = 0; pY-!NoES
else{ ~Er0$+q=Y;
this.startIndex = indexes QVRQUd
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[startIndex / pageSize]; A4|7^Ay
} 9(qoME}>=
} bDIhI}P
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publicint getNextIndex(){ wl%ysM|x
int nextIndex = getStartIndex() + m'
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pageSize; y`8U0TE3R
if(nextIndex >= totalCount) Ym"^Ds}
return getStartIndex(); I
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else Du
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return nextIndex; "=+i~N#Sc
} K|\0jd)N
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publicint getPreviousIndex(){ 0[fBP\H"Wr
int previousIndex = getStartIndex() - @`+\vmfD
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pageSize; wLiPkW
if(previousIndex < 0) _.R]K$U
return0; O-ENFA~E;v
else @YRy)+
return previousIndex; ?/1LueC:
} gx^_bHh
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} 7[0Mr,^
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抽象业务类 L4T\mP7D7*
java代码: |A,.mOT
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/** nC
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* Created on 2005-7-12 h8%QF'C
*/ !-n*]C
package com.javaeye.common.business; >);M\,1\I
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import java.io.Serializable; ^i8biOSZu
import java.util.List; rN7JJHV
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import org.hibernate.Criteria; pg!oi?Jn
import org.hibernate.HibernateException; 8dLmsk^
import org.hibernate.Session; k<j]b^jbz
import org.hibernate.criterion.DetachedCriteria; :-U&_%#w
import org.hibernate.criterion.Projections; @:B}QxC
import Y@q9
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org.springframework.orm.hibernate3.HibernateCallback; (pM&eow}
import THX% z
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org.springframework.orm.hibernate3.support.HibernateDaoS -DJ,<f*$
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upport; As5l36
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import com.javaeye.common.util.PaginationSupport; ltU{P|7!E
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public abstract class AbstractManager extends 6C"zBJcGc
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HibernateDaoSupport { R rH{Y0
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privateboolean cacheQueries = false; [>_zV.X
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privateString queryCacheRegion; GutiqVP:B
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publicvoid setCacheQueries(boolean nL[OwfPj
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cacheQueries){ eHKb`K7C.
this.cacheQueries = cacheQueries; |"KdW#.x
} a(|0'^
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publicvoid setQueryCacheRegion(String DzA'MX
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queryCacheRegion){ eJn_gKWb
this.queryCacheRegion = (RrC<5"
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queryCacheRegion; MK!
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} C8qSoO4Z
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publicvoid save(finalObject entity){ uTz>I'f
getHibernateTemplate().save(entity); {*g{9`
} {,6J*v"o
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publicvoid persist(finalObject entity){ `-cw[@uD
getHibernateTemplate().save(entity); x[)]u8^A
} (nBh6u*
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publicvoid update(finalObject entity){ UUbO\_&y
getHibernateTemplate().update(entity); t>LSP$
} ~#VDJ[Z
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publicvoid delete(finalObject entity){ X7-[#} T
getHibernateTemplate().delete(entity); B]b/(Q+
} z0a`*3 -2
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publicObject load(finalClass entity, 'qde#[VB
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finalSerializable id){ (M
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return getHibernateTemplate().load vg@5`U`^h
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(entity, id); ,JbP~2M~%
} yA*U^:%
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publicObject get(finalClass entity, 5 A5t
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finalSerializable id){ ,Csjb1
return getHibernateTemplate().get P*%P"g
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(entity, id); i|,}y`C#
} H"Hl~ ~U
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publicList findAll(finalClass entity){ 3fX_XH1Q
return getHibernateTemplate().find("from N7}3?wS
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+
" + entity.getName()); PBE i"`i
} aR@+Qf
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publicList findByNamedQuery(finalString S1~K.<B
m J$[X
namedQuery){ r|
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return getHibernateTemplate YSfJUB!I
o@[o6.B<
().findByNamedQuery(namedQuery); #4"eQ*.*"
} r4X\/
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publicList findByNamedQuery(finalString query, umAO&S.+M
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finalObject parameter){ <s|.2~
return getHibernateTemplate ci:|x =
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().findByNamedQuery(query, parameter); (n2_HePE
} 3,*A VcQA
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publicList findByNamedQuery(finalString query, h#)\K|
qs
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finalObject[] parameters){ M0)0~#?.D
return getHibernateTemplate c(b`eUOO
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().findByNamedQuery(query, parameters); -ULgVGYKK
} dWi.V?K4z
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publicList find(finalString query){ X_bB6A6
return getHibernateTemplate().find 8WpNlB+:{
{x..>
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(query); q&NXF(
} {-]K!tWda
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publicList find(finalString query, finalObject N:#$S$
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parameter){ R3piI&u
return getHibernateTemplate().find ;Oq>c=9%
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(query, parameter); i& %dwqp
} b
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public PaginationSupport findPageByCriteria []yIz1P=j
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(final DetachedCriteria detachedCriteria){ 3i4m!g5Z?
return findPageByCriteria >f-RzQ k
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); z^4+Un
} 5
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public PaginationSupport findPageByCriteria gQu!(7WLI
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(final DetachedCriteria detachedCriteria, finalint /M3;~sx
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startIndex){ U;u4ey
return findPageByCriteria Al *yx_j
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(detachedCriteria, PaginationSupport.PAGESIZE, Uqj$itqUQ
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startIndex); i=rA;2>
} ;yjw(OAI*
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public PaginationSupport findPageByCriteria -y3[\zNe
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(final DetachedCriteria detachedCriteria, finalint *&h]PhY
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pageSize, !mwMSkkq
finalint startIndex){ b`DPlQHj
return(PaginationSupport) )u]=^
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getHibernateTemplate().execute(new HibernateCallback(){ _ogN
publicObject doInHibernate %X%f0J
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(Session session)throws HibernateException { *g:Dg I 2
Criteria criteria = Gb"kl.j
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detachedCriteria.getExecutableCriteria(session); #KHj.Vg
int totalCount = B !rb*"[
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((Integer) criteria.setProjection(Projections.rowCount M-+!z5q~d
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()).uniqueResult()).intValue(); C+t|fSJ
criteria.setProjection Z3u6m0!
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(null); dPV<:uO
List items = 5*90t{#
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criteria.setFirstResult(startIndex).setMaxResults qkC{IBN92
+~
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(pageSize).list(); 5s4x%L (~}
PaginationSupport ps = .;,,{;
j9/iBK\Y
new PaginationSupport(items, totalCount, pageSize, g@?R"
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startIndex); }#=t%uZ/
return ps; fmLDufx
} 3{ea~G)[9
}, true); I-kK^_0mV<
} fti0Tz'
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public List findAllByCriteria(final Ar_Yl|a
p -!/p#
DetachedCriteria detachedCriteria){ )lU ocm
return(List) getHibernateTemplate q8R,#\T*
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().execute(new HibernateCallback(){ zpNt[F?~1
publicObject doInHibernate ]'>jw#|h
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(Session session)throws HibernateException { {aopGu?i
Criteria criteria = GFnwj<V+{
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detachedCriteria.getExecutableCriteria(session); n#4T o;CS
return criteria.list(); z$/s` |]
} kaECjZ_&+
}, true); o##!S6:A
} E=,fdyj.
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public int getCountByCriteria(final 2J3y
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DetachedCriteria detachedCriteria){ mWLi XKnb
Integer count = (Integer) 7MKZ*f@x;
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getHibernateTemplate().execute(new HibernateCallback(){ lx~C{tl2
publicObject doInHibernate ys7Tq+
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(Session session)throws HibernateException { &*Kk>
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Criteria criteria = Q
} 0_}W
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detachedCriteria.getExecutableCriteria(session); #??[;xjs!
return T7Ju7_q}
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criteria.setProjection(Projections.rowCount "b)EH/s
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()).uniqueResult(); 1@~ 1vsJ
} eG.s|0`
}, true); YWk+}y}^d
return count.intValue(); Tg=P*HY6
} Tx'anP
} 4:s,e<Tc4v
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用户在web层构造查询条件detachedCriteria,和可选的 9R[PpE''
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 _0iV6Bj
<e@4;Z(h04
PaginationSupport的实例ps。 lpbcpB
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ps.getItems()得到已分页好的结果集 wkJ@#jD*[
ps.getIndexes()得到分页索引的数组 g/w<T+v
ps.getTotalCount()得到总结果数 iBKH\em/
ps.getStartIndex()当前分页索引 od&wfwk(
ps.getNextIndex()下一页索引 dI%N wl%
ps.getPreviousIndex()上一页索引 ow'CwOj$
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ]KUeSg|
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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 >``
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一下代码重构了。 TFXKC l
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我把原本我的做法也提供出来供大家讨论吧: Dh68=F0
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首先,为了实现分页查询,我封装了一个Page类: a3Xd~Qs
java代码: {?}^HW9{
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/*Created on 2005-4-14*/ .k,,PuP
package org.flyware.util.page; "z*?#&?,
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/** /3;]e3x
* @author Joa !~xlze
* /.t1Ow
*/ kJCeQK:W
publicclass Page { {=MRJg!U
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/** imply if the page has previous page */ >h$Q%w{V
privateboolean hasPrePage; -6e^`c6{
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/** imply if the page has next page */ e0]%ko"
privateboolean hasNextPage; j=u)
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/** the number of every page */ 2~yj
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privateint everyPage; P<LmCYm
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/** the total page number */ $qR@;=
privateint totalPage; }>b@=5O
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/** the number of current page */ }V 4u`=
privateint currentPage; 5>VX]nE3!
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/** the begin index of the records by the current MIqH%W.ru
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query */
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privateint beginIndex; qu;$I'Ul%
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/** The default constructor */ HNLr}
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public Page(){ rrG}; A
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} :OA;vp~$x
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/** construct the page by everyPage w,OPM}) il
* @param everyPage PlwM3lrj
* */ R%`fd *g
public Page(int everyPage){ #6C<P!]V
this.everyPage = everyPage; I[n|#N
} tHr4/
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/** The whole constructor */ a>,Zp*V(
public Page(boolean hasPrePage, boolean hasNextPage, 6!([Hu#= *
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int everyPage, int totalPage, :G&:v
int currentPage, int beginIndex){ k+hl6$:Qj%
this.hasPrePage = hasPrePage; VeOM `jy
this.hasNextPage = hasNextPage; wU"w
this.everyPage = everyPage; (#]9{C;
this.totalPage = totalPage; 7t/Y5Qf
this.currentPage = currentPage; h\+8eeIl
this.beginIndex = beginIndex; Y3SV6""y/
} 28 zZ3|Z3
uII! ?
/** Qm_;o(
* @return }#&L
* Returns the beginIndex. $"?$r
*/ {e0(M*u
publicint getBeginIndex(){ z|zEsDh;
return beginIndex; #8y"1I=i&
} wn\R|'Rdz
v4Kf{9q#
/** ]2A2<Q_,
* @param beginIndex ?6h~P:n.
* The beginIndex to set. n3$u9!|P
*/ 3#eAXIW[
publicvoid setBeginIndex(int beginIndex){ -vc
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this.beginIndex = beginIndex; +x<OyjY5?]
} L^K,YlNBR
bgkBgugZhX
/** KDj/S-S
* @return 86a,J3C[
* Returns the currentPage. hDc2T
*/ 7\gu; [n
publicint getCurrentPage(){ o'8%5M@
return currentPage; }rF4M1+B\
} TV`sqKW
G"".;}AV
/** j3u!lZ}U
* @param currentPage !>/J]/4>
* The currentPage to set. i(V
*/ !/X>k{
publicvoid setCurrentPage(int currentPage){ \S{ihS@J
this.currentPage = currentPage; {Z178sik
} d<E2=WVB6
U~dqxR"Q
/** WC
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* @return ?yu@eo
* Returns the everyPage. <&bBE"U4
*/ (0rcLNk{|
publicint getEveryPage(){ 8G3.bi'q
return everyPage; )}Cf6m}
} yw1Xxwc
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/** P/Y)Yx_(
* @param everyPage ac1(lD
* The everyPage to set. p\Iy)Y2Lf!
*/ \tCK7sBn
publicvoid setEveryPage(int everyPage){ RJ{J~-q{
this.everyPage = everyPage; yV31OBC:
} 5'%O]~
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/** '{cFr
* @return 6rO^ p
* Returns the hasNextPage. `G=+qti
*/ LLoV]~dvUu
publicboolean getHasNextPage(){ LLMGs: [
return hasNextPage; 'R99m?"
} %/ :&L+q
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/** ,wy;7T>ODd
* @param hasNextPage Y@qugQM>
* The hasNextPage to set. ^N`KT
*/ yN06` =
publicvoid setHasNextPage(boolean hasNextPage){ w7 \vrS>&
this.hasNextPage = hasNextPage; e)3Mg^
} GoPMWbI7
@gQ?cU 7
/** \g v-2.,
* @return )Lk2tvr
* Returns the hasPrePage. k?/! `
*/ RN;#H_
q
publicboolean getHasPrePage(){ $>Ow<!c
return hasPrePage; `>RM:!m6=$
} h]IoH0/
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/** JV+Uy$P!
* @param hasPrePage :`0,f ?cE
* The hasPrePage to set. P]L%$!g
*/ $#wi2Ve=6b
publicvoid setHasPrePage(boolean hasPrePage){ O"_QDl<ya
this.hasPrePage = hasPrePage; Lmw)Ts>
} A{\DzUV9,
[g{fz3
O6
/** >)mF'w
* @return Returns the totalPage. KvI/!hl\
* "cbJ{ G1pk
*/ `iEYq0}
publicint getTotalPage(){ &v9"lR=_k
return totalPage; >4HB~9dKU
} cBHUa}:
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/** Wul8ej:
* @param totalPage %{me<\(
* The totalPage to set. f/Z-dM\e
*/ vq@"y%C4
publicvoid setTotalPage(int totalPage){ VP7LKfv
this.totalPage = totalPage; 0/cgOP!^
} 6vzvH
U8%IpI;
} E^~ {thf
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pTJ_DH
)5Cqyp~P
>z,Y%A
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 R1.Yx?
8-smL^~%#
个PageUtil,负责对Page对象进行构造: y;O
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java代码: 49Y:}<Yd
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/*Created on 2005-4-14*/ 0|4R8Dh*-
package org.flyware.util.page; j9cB<atL
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import org.apache.commons.logging.Log; U<'$ \P
import org.apache.commons.logging.LogFactory; Eh"Y<]$
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/** H/*i-%]v+(
* @author Joa ")fgQ3XZ
* K5(T7S
*/ x26 sH5
publicclass PageUtil { HhzP Kd
j",*&sy
privatestaticfinal Log logger = LogFactory.getLog 1o)<23q`)
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(PageUtil.class); Gr3 q
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/** Q0xQxz
* Use the origin page to create a new page Z(J
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* @param page 8"u.GL.
* @param totalRecords ?w)A`G_
* @return i_I`
*/ 475jmQ{q
publicstatic Page createPage(Page page, int zD
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totalRecords){ >q&e.-qL
return createPage(page.getEveryPage(), h@s i)5"
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page.getCurrentPage(), totalRecords); +ERuZc$3,
} paxZlA
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/** u#->?
* the basic page utils not including exception q z!^<
M
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handler qtP*O#1q
* @param everyPage uYd_5
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* @param currentPage g~OG~g@
* @param totalRecords zS?DXE
* @return page 4XeO^#
*/ @*$"6!3s5
publicstatic Page createPage(int everyPage, int 7 S%`]M4;
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currentPage, int totalRecords){ V.o*`V
everyPage = getEveryPage(everyPage); J!'IkC$>
currentPage = getCurrentPage(currentPage); >Q)S-4iR
int beginIndex = getBeginIndex(everyPage, %\%&1
mn\GLR.
currentPage); Qb:.WMj[q+
int totalPage = getTotalPage(everyPage, XK(aH~7xme
nYK!'x$
totalRecords); vE~<R
boolean hasNextPage = hasNextPage(currentPage, 4 @9cO)m
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totalPage); &7c #i
boolean hasPrePage = hasPrePage(currentPage); tTJ$tx
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returnnew Page(hasPrePage, hasNextPage, ?Y9VviC
everyPage, totalPage, B^x}=Z4
currentPage, Fk?KR
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beginIndex); h:vI:V[/X
} TG.\C8;vFh
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privatestaticint getEveryPage(int everyPage){ 57$/Dn
return everyPage == 0 ? 10 : everyPage; ;ZZmX]kz,M
}
<XnxAA
QwI HEmdM
privatestaticint getCurrentPage(int currentPage){ "3?:,$*
return currentPage == 0 ? 1 : currentPage; k:1|Z+CJ
} _%aT3C}k
H]Gj$P=k
privatestaticint getBeginIndex(int everyPage, int hud'@O"R+
,9.NMFn
currentPage){ 0fR?zT?
return(currentPage - 1) * everyPage; D\sh
+}"
} ]Vf2Mn=]"
AE%zqvp>
privatestaticint getTotalPage(int everyPage, int ' PmBNT
~hU^5R-%
totalRecords){ 'W[Nr
int totalPage = 0; CWnRRZ}r
JZD&u6tB
if(totalRecords % everyPage == 0) r / L
totalPage = totalRecords / everyPage; l{_1`rC'
else &|Vzo@D(!
totalPage = totalRecords / everyPage + 1 ; }z2K"eGt
]tEH `Kl
return totalPage; o(xt%'L`t
} vu/P"?F
LeMo")dk\
privatestaticboolean hasPrePage(int currentPage){ jL~. =QD
return currentPage == 1 ? false : true; 8;Df/%
} hx@E,
@ds.)sKA>
privatestaticboolean hasNextPage(int currentPage, :?7^STc
rf$eg
int totalPage){ bw[K^/
return currentPage == totalPage || totalPage ==
~&_BT`a
`I5So-^&z
0 ? false : true; b"~Ct}6f
} DQ_ pLXCC
d^XRkB:h
)`m/vYKWL
} qTnk>g_oS&
K.6xNQl{}
O,7*dniH
H=_k|#/
Bj\ oo+L/
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 /f,*|
gUv`G
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 HQ3kxOT
*lp{,
做法如下: P vS\
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 1?T^jcny:M
6XGqZ!2
的信息,和一个结果集List: h)yAge
java代码: j}$Q`7-wB1
&0euNHH;sL
BoPJ;6?>}
/*Created on 2005-6-13*/ B,ZLX/c9
package com.adt.bo; #^<Rx{
I~7eu&QZ
import java.util.List; B_|jDH#RyJ
x^6sjfAW
import org.flyware.util.page.Page; \jByJCN
dn=g!=
/** 62J-)~_
* @author Joa BO-=X
78f@
*/ /;rk-I
publicclass Result { y Ide]
wqf^n-Ze
private Page page; sVT\e*4m}
=h}IyY@o
private List content; J"]P"`/
{K+]^M
/** $5#+;A'Q+
* The default constructor :jljM(\
*/ LXcH<)
public Result(){ =Ev*Q[
super(); q|ww fPez7
} R9V v*F]m@
5y|/}D>
/** a`uHkRX
)U
* The constructor using fields {t<U:*n2
* `$N AK
* @param page L\H,cimN
* @param content [|\BuUT'
*/ \^rAH@
public Result(Page page, List content){ M\ {W &o1!
this.page = page; c{s%kVOzg
this.content = content; H-1y2AQ
} 1t7S:IZ
?3:xR_VWZu
/** Z,m;eCLG]
* @return Returns the content. mkOj&Q
*/ 9DP6g<>B
publicList getContent(){ ,Q8)r0 c
return content; fu?Y'Qet
} RzLbPSTQ
Ok&u4'<
/** w6[uM%fHG
* @return Returns the page. #97w6,P+
*/ f_GqJ7Gk]
public Page getPage(){ N_"mC^Vx
return page; :3Hr:~
} 5n'C6q "
!`%3?}mv,
/** VXtW{*{"
* @param content C~dD'Tq]
* The content to set. i@}/KT
*/ U[UjL)U
public void setContent(List content){ !mLYW
this.content = content; 5>'1[e45
} }2eP~3
i''[u
/**
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* @param page a,sU-w!X'
* The page to set. h&}XG\ioNA
*/ kmXaLt2Z
publicvoid setPage(Page page){ .oFkx*Ln
this.page = page; >>C(y?g
} HO(9)sK
} U^$o<2
*@2?_b}A
^
m# ]VdO'f
k6vY/)-S
v&GBu
2. 编写业务逻辑接口,并实现它(UserManager, 8s_'tw/{
ovn)lIs
UserManagerImpl) ^gpswhp
5
java代码: *MFsq}\ $
T6g(,xPcL
O67.DEu^
/*Created on 2005-7-15*/ vUXas*s4
package com.adt.service; <e
'S'
j7|r^
import net.sf.hibernate.HibernateException; ?Rj)x%fN
ie!ik
import org.flyware.util.page.Page; _ ecKX</Q
qh)o44/
$
import com.adt.bo.Result; SDTX3A1
dfBTx6/F
/** xxh(VQdg
* @author Joa U`es
n?m!
*/ MDCK@?\
publicinterface UserManager { l`s_#3
k]=Yi;
public Result listUser(Page page)throws $6a55~h|(
=sk]/64h``
HibernateException; }. x&}FqXE
i#M$i*H*A
}
d!%:Ok
4epE!`z_&
i(XcNnn6
:b&O{>M]Y
5X5 &(S\
java代码: 8uR4ZE*
`eat7O
Vb`m3
/*Created on 2005-7-15*/ a~_5N&~pi
package com.adt.service.impl; 8pfQAzl
ZS@Cd9*
import java.util.List; ptXLWv`
4A_}:nU
import net.sf.hibernate.HibernateException; %z&=A%'a
]R8}cbtU
import org.flyware.util.page.Page; ROr..-[u
import org.flyware.util.page.PageUtil; +IiL(\ew
~7tG%{t%
import com.adt.bo.Result; u:Q_XXT5
import com.adt.dao.UserDAO; S"iz
fQ@
import com.adt.exception.ObjectNotFoundException; UGNFWZ c
import com.adt.service.UserManager; {]aB3
&n.7~C]R
/** C~.7m-YW
* @author Joa AKVll
*/ gu[3L
publicclass UserManagerImpl implements UserManager { h^h!OQK Q
|RBgJkS;8
private UserDAO userDAO; .6yC' 3~;o
#TLqo(/
/** C< GS._V&
* @param userDAO The userDAO to set. ceDe!Iu
*/ H=OKm
publicvoid setUserDAO(UserDAO userDAO){ xA DjQ%B
this.userDAO = userDAO; .R/`Y)4
} |@]`" k
}%B^Vl%ZZ
/* (non-Javadoc) ~G!>2 +L
* @see com.adt.service.UserManager#listUser F^Yt\V~T
15i8) 4h
(org.flyware.util.page.Page) `Trpv$
*/ 7tgn"wK
public Result listUser(Page page)throws cNzn2-qv
v*+.;60_
HibernateException, ObjectNotFoundException { 'OKDB7Ni
int totalRecords = userDAO.getUserCount(); 1>$fLbmkI
if(totalRecords == 0) 6>! ;g'k
throw new ObjectNotFoundException ho#]i$b}f2
MXWCYi
("userNotExist"); ;Jex#+H(:D
page = PageUtil.createPage(page, totalRecords); V&x6ru#
List users = userDAO.getUserByPage(page); 6vrMR&#a
returnnew Result(page, users); "pb,|U
} IG?044Y
`Z*k M VN
}
hfpSxL
D}1Z TX_
!JtVp&?
x?0ZzB),
s)dN.'5/
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Aen)r@Y:
u:r'jb~@
询,接下来编写UserDAO的代码: 1=x4m=wV
3. UserDAO 和 UserDAOImpl: iq> PN:mr
java代码: ?:(BkY,K5
PSX-b)wb
t&+f:)n
/*Created on 2005-7-15*/ "oX@Z^
package com.adt.dao; /
lh3.\|
x4jn45]x@
import java.util.List; #F\}PCBe'
5`oVyxJ<
import org.flyware.util.page.Page; }R#YO$J7
a $pxt!6
import net.sf.hibernate.HibernateException; <4,n6$E
>r] bfN,
/** JTw\5j
* @author Joa -EV_=a8[y
*/ \hpD
publicinterface UserDAO extends BaseDAO {
GU99!.$
6@`Y6>}$_
publicList getUserByName(String name)throws UxZT&x3=)}
Zvd^<SP<?
HibernateException; }~Z1C0t
Pa PQ|Pwz
publicint getUserCount()throws HibernateException; ]+O];*T
e;:~@cB,c
publicList getUserByPage(Page page)throws ", b}-B
,/n<Qg"`
HibernateException; <X}@afS
L4I1n l
} zG|}| //}
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\;
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deR2l(0%yr
7(<6+q2~
java代码: -`FPR4;
G<9UL*HU
8YJ8_$Z
/*Created on 2005-7-15*/ ^a~^$PUqI
package com.adt.dao.impl; ~W'>L++
wehZ7eqm
import java.util.List; "Gx(-NH+
5#+G7 'k
import org.flyware.util.page.Page; g6:S"Em
G"3)\FEM
import net.sf.hibernate.HibernateException; o*7`r ~
import net.sf.hibernate.Query; Zf~Em'g"3
Gp.+&\vi
import com.adt.dao.UserDAO; ^sxcBG
|,c\R"8xS
/** :d7Ju.*J
* @author Joa `N%q^f~
*/ ^<fN
public class UserDAOImpl extends BaseDAOHibernateImpl oTj9 /r
AyZL(
implements UserDAO { P#5&D*`}h
`~'yy q
/* (non-Javadoc) M&Aeh8>uX
* @see com.adt.dao.UserDAO#getUserByName $i&u\iL
"*O(3L.c-
(java.lang.String) epa)~/sA
*/ .K>rao'
publicList getUserByName(String name)throws 6XPf0Gl
..RCR_DIp
HibernateException { 1Wzm51RU
String querySentence = "FROM user in class .JIn(
XPnN"Y"y
com.adt.po.User WHERE user.name=:name"; ,B]kX/W
Query query = getSession().createQuery p`ai2`qC`
DDh$n?2fd
(querySentence); QEIu}e6b
query.setParameter("name", name); ;C,D1_20Z
return query.list(); iXpLcHi
} _Wn5*
Pi%Z
-gZI^EII
/* (non-Javadoc) U JO
* @see com.adt.dao.UserDAO#getUserCount() |V#h
"s
*/ >q0c!,Ay
publicint getUserCount()throws HibernateException { 4$D:<8B
int count = 0; I9GRSm;0<
String querySentence = "SELECT count(*) FROM JR='c)6:
yM(zc/?
user in class com.adt.po.User"; >,22@4
Query query = getSession().createQuery <t[WHDO`
S'"(zc3=
(querySentence); __jFSa`at
count = ((Integer)query.iterate().next 5nL,sFd
z.itVQs$I
()).intValue(); qE73M5L&
return count; sr(f9Vl
} 0^htwec!
/(-X[[V
/* (non-Javadoc) qI,4uGg
* @see com.adt.dao.UserDAO#getUserByPage }{<@wE%s
V<f76U)
(org.flyware.util.page.Page) KCG-&p$v@s
*/ (~t/8!7N
publicList getUserByPage(Page page)throws ^|KX)g
f(Jz*el
S
HibernateException { z?V'1L1gM
String querySentence = "FROM user in class \yeo-uN8
1RC(T{\x
com.adt.po.User"; /lBx}o'
Query query = getSession().createQuery > D:(HWL
GY9CU=-
(querySentence); A
i`
query.setFirstResult(page.getBeginIndex()) PfKIaW<
.setMaxResults(page.getEveryPage()); =#qf0
return query.list(); Vm
NCknG
} ?`%7Y~
>*v!2=
} IN2FO/Y@
ZujPk-
P)he3
x5/O.5>f
)L}6to
至此,一个完整的分页程序完成。前台的只需要调用 9Tbi_6[
F)x^AJie
userManager.listUser(page)即可得到一个Page对象和结果集对象 <0!/7*;#ZT
]<\FtH
的综合体,而传入的参数page对象则可以由前台传入,如果用 8:V:^`KaSs
>gNVL
(
webwork,甚至可以直接在配置文件中指定。 `4V_I%lJ&
$ K>.|\
下面给出一个webwork调用示例: y#-mj,e
java代码: OmO/x
9Yg=4>#$
3=(Gb
/*Created on 2005-6-17*/ (gd+-o4
package com.adt.action.user; hVPSW# .d
uH'n.d"WG
import java.util.List; 6J3:[7k=&
*T(z4RVg
import org.apache.commons.logging.Log; g~EJja;
import org.apache.commons.logging.LogFactory; FSnF>3kj-
import org.flyware.util.page.Page; WZkAlg7Z
lFMQT
;
import com.adt.bo.Result; @SA:64
9
import com.adt.service.UserService; "/v{B?~%!
import com.opensymphony.xwork.Action; ~4HS
2\
*z-Mr~V
/** `/en&l
* @author Joa -X#Zn>#
*/ =bt/2nPV
publicclass ListUser implementsAction{ {ir8n731p
'xO5Le(=M
privatestaticfinal Log logger = LogFactory.getLog >U/m/H'
#sLyU4QV
(ListUser.class); )%D2JC
@SH%l]
private UserService userService; x^_(gve:
JVO,@~~
private Page page; 7`,A]":;
7}+U;0,)
privateList users; xE+Nz5F
1t"
/* <[9{Lg*D
* (non-Javadoc) o' U::
* k)+2+hX&>
* @see com.opensymphony.xwork.Action#execute() NY.Y=CF("
*/ h *J=F0KM
publicString execute()throwsException{ 9H$$Og
Result result = userService.listUser(page); k"-2OT
page = result.getPage(); V-Ebi^gz5W
users = result.getContent(); # fvt:iE
return SUCCESS; 7]}n0*fe
} \nQV{J
l (;~9u0sa
/** q'u^v PO
* @return Returns the page. o&tETJ5Bhe
*/ 0OJBC~?{\
public Page getPage(){ *`]LbS
return page; EjZ_|Q
} bDh,r!I
:q6j{C(
/** H^UuT
* @return Returns the users. }Yd7<"kp
*/ ,9T-\)sT
publicList getUsers(){ q'r(#,B<3
return users; 7A!E~/nSC
} JO\F-xO
:__z?<?(
/** KW^#DI6tr
* @param page qY^OO~[
* The page to set. ]Puu: IG
*/ E3IB> f
publicvoid setPage(Page page){ S!*wK-
this.page = page; -rC_8.u :
} KMFvi_8
RzPqtN
/** ";:"p6?
* @param users u=epnz:<
* The users to set. fQZ,kl
*/ yk1.fxik'
publicvoid setUsers(List users){ AcF6p)@_
this.users = users; P+tnXT>nE
} zoFCHsr
ZaxBr
/** sxac(L
* @param userService \F_~?$
* The userService to set. -oSfp23u
*/ mJjd2a"vi
publicvoid setUserService(UserService userService){ !U}dYB:O
this.userService = userService; .c#G0t<i[
} }bwH(OOS
} Bismd21F6=
e;QPn(
{<\ [gm\X
-)S(eqq1
g=8}G$su{%
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, )?@X{AN&
/5@4}m>Z@
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 :Taequk
6 w"-&
么只需要: +4<Ij/}p
java代码: zR)9]pJ-
KW&5&~)2
y[ikpp#ozY
<?xml version="1.0"?> tS1(.CRk
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 'q+CL&D
9NX/OctFa'
1.0//EN" "http://www.opensymphony.com/xwork/xwork- Dwvd
pq<302uBQ
1.0.dtd"> 3v oas
y _Mte
<xwork> J<[Hw g
?f9@
<package name="user" extends="webwork- nq9|cS%-
}jF67c->
interceptors"> 8Ja't8
D;~c`G
"f
<!-- The default interceptor stack name
4d\1W?i-
4dfR}C
--> Ygwej2
<default-interceptor-ref <$#;J>{WV
(%`R{Y
name="myDefaultWebStack"/> gpo+-NnG
Ebmd[A&&
<action name="listUser" (QARle(i
$j ZU(<4,
class="com.adt.action.user.ListUser"> <{
Z$!]i1
<param %hEhZW{:
Oy>V/
name="page.everyPage">10</param> $Tc"7nYu
<result W{z7h[?5,
3bMQ[G
name="success">/user/user_list.jsp</result> a!n |/9
6
</action> BQ\o?={
6Dx^$=Sa$
</package> =3~u.iq$
:cx}I
</xwork> @Yv+L)
*3,Kn}ik
fT:a{
#M9rt~4
-+#QZ7b
Vh%=JL
sK
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 Lm-yTMNPn
FZUN*5`
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。 w_O3];
ynWF Y<VX
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 ukZ>_ke`+
/hNZ7\|P
@zz4,,]
G)vq+L5%
YIb=rR[ $
我写的一个用于分页的类,用了泛型了,hoho 3k5C;5
L=Pz0
java代码: 3,x|w
nhbCk6Y5LZ
WyO7,Qr\
package com.intokr.util; a{oG[e
38I .1p9
import java.util.List; @U~i<kt
Wr3).m52}P
/** >= G{.H
* 用于分页的类<br> Zx%ib8|j
* 可以用于传递查询的结果也可以用于传送查询的参数<br> $i:wS=
w'
* 2YU-iipdOq
* @version 0.01 -F7GUB6B
* @author cheng j,HUk,e^&
*/ tC4:cX
public class Paginator<E> { `^mPq?f
privateint count = 0; // 总记录数 3bCb_Y
privateint p = 1; // 页编号 @raw8w\Zj+
privateint num = 20; // 每页的记录数 @W{VT7w
privateList<E> results = null; // 结果 &}YJ"o[I
Py&DnG'H
/** 'G6M:IXno
* 结果总数 dtXAEL\q
*/ mX4u#$xs:
publicint getCount(){ Z= 'DV1A$,
return count; "ggViIOw&
} 2HxT+|~d6
88K=jo))b
publicvoid setCount(int count){ ?1DA
this.count = count; s>pOfXIx
} ,3m]jp'
IvW%n(a8^
/** s8/sH];
* 本结果所在的页码,从1开始 f3g#(1
* uQ} 0hs
* @return Returns the pageNo. `oDs]90
*/ %[l*:05
publicint getP(){ \R m2c8Z2
return p; x]1G u
} K`BNSdEN>
#_A <C+[
/** $r>\y (W
* if(p<=0) p=1 lphELPh
* \0{g~cU4
* @param p 2
/rDi
*/ $p(,Qz(.8
publicvoid setP(int p){ FuA8vTV{
if(p <= 0) y([""z3<w
p = 1; %Ydzzr3
this.p = p; M[;N6EJH
} Qh3V[br
QG|KZ8uO
/** vf|lF9@U
* 每页记录数量 } Fw/WD
*/ gK`o;` ^
publicint getNum(){ xh7[{n[;
return num; NI@$"
} >.tP7=
Ps0g
/** FN25,Q8:*I
* if(num<1) num=1 '1$#onx
*/ C4#E N}
publicvoid setNum(int num){ JTK0#+?
if(num < 1) #[4Mw M3
num = 1; VcLB0T7m\
this.num = num; 01/?
} UL46%MFQ\
#6jdv|fu
/** r_5k$u(
* 获得总页数 6I)1[tU
*/ dzK]F/L]
publicint getPageNum(){ j:JM v
return(count - 1) / num + 1; vlHE\%{
} x6d0yJ <
h`_@eax
/** @V9qbr=Z
* 获得本页的开始编号,为 (p-1)*num+1 TQcEe@$)
*/ h-^7cHI}
publicint getStart(){ L>,j*a_[
return(p - 1) * num + 1; @YH<Hc
} P3due|4M
#4?(A[]>H
/** ndsu}:my
* @return Returns the results. |5ifgSZ
*/ f;Iaf#V_
publicList<E> getResults(){ H-*"%SJ
return results; .^?^QH3
} #rE#lHo
DeMF<)#
public void setResults(List<E> results){ <])w@QOA#
this.results = results; f/FK>oUh
} c|kQ3(
;[)t*yAh
public String toString(){ liYR8 D
|
StringBuilder buff = new StringBuilder 5M.KF;P
97$1na3gq
(); #WOb&h
buff.append("{"); 7c:5Ey
buff.append("count:").append(count); jq4'=L$4
buff.append(",p:").append(p); 4z~%gt74O]
buff.append(",nump:").append(num); 6l{=[\.Xa
buff.append(",results:").append j3!]wolY
<2\4eusk
(results); LPg1 G+e
buff.append("}"); @Ju!|G9z/p
return buff.toString(); NwK(<dzG
}
Ji>
m &U
$V
} o9tvf|+z
-rEg(@S %
t`"]"Re