Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 _ME?o
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 h<i.Z7F;tj
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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 {BZ0x2
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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 :3D[~-/S
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分页支持类: 64D4*GQ
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java代码: 0>:`|IGnT2
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package com.javaeye.common.util; }]. |7h
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import java.util.List; .jl^"{@6
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publicclass PaginationSupport { R^rA.7T
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publicfinalstaticint PAGESIZE = 30; ^9XAWj"
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privateint pageSize = PAGESIZE; KJ_L>$
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privateList items; be'&tsZ9
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privateint totalCount; M] W5%3do
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privateint[] indexes = newint[0]; ^?T,>ZI
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privateint startIndex = 0; mWuhXY^Q
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public PaginationSupport(List items, int !={QL :
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totalCount){ ar@ysBy
setPageSize(PAGESIZE); $'b b)@_
setTotalCount(totalCount); g$mqAz<
setItems(items); ,62BZyT,T,
setStartIndex(0); a2H_8iQ!
} EiWd =jDm
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public PaginationSupport(List items, int B9oB5E
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totalCount, int startIndex){ *'R2Lo<C
setPageSize(PAGESIZE); -3C$br
setTotalCount(totalCount); K_V$ ktL
setItems(items); g'V,K\TG
setStartIndex(startIndex); qGie~S ##
} &XSe&1
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public PaginationSupport(List items, int 62#8c~dL
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totalCount, int pageSize, int startIndex){ rE\.[mFI
setPageSize(pageSize); hj[sxC>z5
setTotalCount(totalCount); #^q@ra
setItems(items); "`5BAv;u
setStartIndex(startIndex); \fL:Ie
} 7,3v,N|
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publicList getItems(){ SMh[7lU`
return items; sB`zk[R;
} i%9xt1c_
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publicvoid setItems(List items){ }C&kzJBEF
this.items = items; ,T7(!)dR
} i- r y5x
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publicint getPageSize(){ Mhg_z.Z
return pageSize; Y ptP_R:2p
} g
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publicvoid setPageSize(int pageSize){ 5K?%Eo72!=
this.pageSize = pageSize; >"+bL6#
} Sc&p*G
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publicint getTotalCount(){ 8BwJWxBQ
return totalCount; 1fb!sbGD.k
} I ?i,21:5
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publicvoid setTotalCount(int totalCount){ ,Mw;kevw
if(totalCount > 0){ JZB@K6 ~dO
this.totalCount = totalCount; *|k/l I
int count = totalCount / W=T,hOyh<W
5*7
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pageSize; FBJ Lkg0
if(totalCount % pageSize > 0) d/`Q,Vl
count++; "+J[7p}`@
indexes = newint[count]; yTL<S '
for(int i = 0; i < count; i++){ j#E&u*IR
indexes = pageSize * ' fP`ET5
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} "+:IA|1wD
}else{ 6,;7iA]
this.totalCount = 0; xBi``x2eY
} . 'rC'FT
} F%>`?NG+c
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publicint[] getIndexes(){ sj0{;>>%+N
return indexes; Rck k
} ZJ|'$=lR
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publicvoid setIndexes(int[] indexes){ 73OYHp_j
this.indexes = indexes; 9n[ovX 7n!
} !c8hER!
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publicint getStartIndex(){ Da"GYEC
return startIndex; J 4OgV?
} CA{(x(W\:
S
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publicvoid setStartIndex(int startIndex){ Td6"o&0A!
if(totalCount <= 0) Iz[ T.$9
this.startIndex = 0; ![*7HE>},
elseif(startIndex >= totalCount) i5 F9*
this.startIndex = indexes ,HE +|y#
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[indexes.length - 1]; oCftI':@
elseif(startIndex < 0) $pg1Av7l
this.startIndex = 0; `upxM0gc
else{ A(Ss:7({
this.startIndex = indexes #U j~F
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[startIndex / pageSize]; uY6|LTK&x
} E}WO?xxv74
} R2[-Q"|Ra
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publicint getNextIndex(){ (\M&Q-xZ
int nextIndex = getStartIndex() + V]$Tbxg
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pageSize; .s!qf!{V`
if(nextIndex >= totalCount) x)<Hr,wd
return getStartIndex(); U oiXIf_Q
else a5AD$bP
return nextIndex; BL^8gtdn
} _v9P0W^.7
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publicint getPreviousIndex(){ VV1I2YcKt
int previousIndex = getStartIndex() - ?$#,h30
,{br6*E
pageSize;
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if(previousIndex < 0) cj!Ew}o40D
return0; "/zIsn7
else 0ThX1)SH
return previousIndex; viJK%^U=-
} ^<}eONa
LZB=vc|3/
} +W6QtB6
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抽象业务类 d}.*hgk
java代码: }smPP*
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/** BSGC.>$s
* Created on 2005-7-12 A80r@)i
*/ 5Cp6$V|/kv
package com.javaeye.common.business; Jmp%%^
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import java.io.Serializable; J^J$I!
import java.util.List; 1$*ZN4
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import org.hibernate.Criteria; C#r1zr6
import org.hibernate.HibernateException; />Z`?
import org.hibernate.Session; /2!Wy6p
import org.hibernate.criterion.DetachedCriteria; VoOh$&"M
import org.hibernate.criterion.Projections; 'V=i;2mB*
import D[7+xAwS
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org.springframework.orm.hibernate3.HibernateCallback; \D9J!K82
import W?n)IBj8
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org.springframework.orm.hibernate3.support.HibernateDaoS 0.9%m7.m
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upport; fr\"MP
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import com.javaeye.common.util.PaginationSupport; _NfdJ=[Xh
}-ly'4=l
public abstract class AbstractManager extends mM> L0
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HibernateDaoSupport { R d?8LLz
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privateboolean cacheQueries = false; %yjz@
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privateString queryCacheRegion; aDV~T24
ps DY}y\"
publicvoid setCacheQueries(boolean PJ-EQ6W
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cacheQueries){ Ej\Me
this.cacheQueries = cacheQueries; 0^H"eQO
} N-0kB vo
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publicvoid setQueryCacheRegion(String H{}Nr
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queryCacheRegion){ r%c raf
this.queryCacheRegion = H2ZRUFu
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queryCacheRegion; <|!?V"`3
} JE a~avyJ
q X"Pg
publicvoid save(finalObject entity){
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getHibernateTemplate().save(entity); 6.!aJJLN
} -`I&hzl6E
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publicvoid persist(finalObject entity){ 6T?$m7c
getHibernateTemplate().save(entity); $s2Y,0>I6
} >@Nn_d
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publicvoid update(finalObject entity){ sjZ@}Vk3b
getHibernateTemplate().update(entity); jkVX>*.|oy
} agbG) t0
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publicvoid delete(finalObject entity){ C[-M
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getHibernateTemplate().delete(entity); m@Q%)sc)
} ^69ZX61vt
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publicObject load(finalClass entity, KW&vX%i(.
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finalSerializable id){ TtWE:xE
return getHibernateTemplate().load fn~Jc~[G|
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(entity, id); >" &&,~
} .|VWYN
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publicObject get(finalClass entity, nNEIwlj;
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finalSerializable id){ fz[-pJ5[
return getHibernateTemplate().get 38gHM9T
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(entity, id); 4Odf6v,*@
} 6^+T_{gl
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publicList findAll(finalClass entity){ M>yt\qbkA
return getHibernateTemplate().find("from k-;A9!^h
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" + entity.getName()); C-TATH%f^
} `{B<|W$=
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publicList findByNamedQuery(finalString ol7^T
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namedQuery){ .szc-r{
return getHibernateTemplate w vQ.9
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().findByNamedQuery(namedQuery); a9sbB0q-K@
} S_|VlI
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publicList findByNamedQuery(finalString query, fJdTVs@
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finalObject parameter){ HC$rC"f
return getHibernateTemplate ^rX5C2}G\D
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().findByNamedQuery(query, parameter); B']}n`g
} |{j\7G*5
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publicList findByNamedQuery(finalString query, tm#[.
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finalObject[] parameters){ so]p1@K
return getHibernateTemplate $;Nw_S@
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().findByNamedQuery(query, parameters); ySP%i6!au
} vkK8D#K
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publicList find(finalString query){ EjjW%"C,
return getHibernateTemplate().find 8_h:_7e
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(query); v9K=\ j
} .Z#8,<+
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publicList find(finalString query, finalObject 4Mr)~f rc
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parameter){ L8.u7(-#
return getHibernateTemplate().find *3s,~<''%
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(query, parameter); +h?Rb3=S
} KpF/g[m
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public PaginationSupport findPageByCriteria Zf*DC~E_
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(final DetachedCriteria detachedCriteria){ ^sb+|b
return findPageByCriteria 7a5G,C#QQ
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); >@+ r|
} C[2LP$6*/
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public PaginationSupport findPageByCriteria }:9UI
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(final DetachedCriteria detachedCriteria, finalint -l i71.M
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startIndex){ Q2jl61d_9
return findPageByCriteria A>Y!d9]ti
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(detachedCriteria, PaginationSupport.PAGESIZE, gVU&Yl~/^
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startIndex); & 8'QD~
} ^,,lo<d_L
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public PaginationSupport findPageByCriteria Y>a2w zr
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(final DetachedCriteria detachedCriteria, finalint NI)q<@ju
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pageSize, <h[l)-86
finalint startIndex){ r}~|,O3bc'
return(PaginationSupport) b]XDfe
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getHibernateTemplate().execute(new HibernateCallback(){ X0+M|8:
publicObject doInHibernate kf>L
q A?j-H
(Session session)throws HibernateException { [X=J]e^D
Criteria criteria = g4CdzN~
&.`/ln
detachedCriteria.getExecutableCriteria(session); !Q" 3B6
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int totalCount = mvrg!/0w
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((Integer) criteria.setProjection(Projections.rowCount & GM&,
v.pj
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()).uniqueResult()).intValue(); i=DoK{`L
criteria.setProjection J2P5<
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(null); WTZr{)e
List items = Lf} @v
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criteria.setFirstResult(startIndex).setMaxResults q)E
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(pageSize).list(); "i3Q)$"S
PaginationSupport ps =
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new PaginationSupport(items, totalCount, pageSize, ' *x?8-K P
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startIndex); xs ^$fn\
return ps; w+Cs=!
} q9`!T4,
}, true); ]/C1pG*o
} Mk"V%)1k
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public List findAllByCriteria(final p"XQJUuD
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DetachedCriteria detachedCriteria){ (HZzA7eph
return(List) getHibernateTemplate Axtf,x+lH
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().execute(new HibernateCallback(){ V$7SVq
publicObject doInHibernate qp@:Zqz8
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(Session session)throws HibernateException { &v#*
Criteria criteria = &%/kPF~<
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detachedCriteria.getExecutableCriteria(session); e2?7>?
return criteria.list(); @'yD(ZMAz
} RW@sh9
}, true); TLk=HGw
} !Xbr7:UPN1
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public int getCountByCriteria(final J}-,!3qxW
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DetachedCriteria detachedCriteria){ <Eo;CaaF/
Integer count = (Integer) K8l|qe
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getHibernateTemplate().execute(new HibernateCallback(){ N}*|*!6hI
publicObject doInHibernate |W/_S^ C
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(Session session)throws HibernateException { 4oF8F)ASj
Criteria criteria = lF\oEMd*
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detachedCriteria.getExecutableCriteria(session); (Hcd{]M~
return W:7oGZ>4
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criteria.setProjection(Projections.rowCount 0.~Pzg
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()).uniqueResult(); WJ9= hr
} CE$c/d[N.
}, true); v[_C^;
return count.intValue(); OgiElA.
} 7J]tc1-re
} @}K'Ic
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用户在web层构造查询条件detachedCriteria,和可选的 u6AReL'f
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 SsDe\"?Q
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PaginationSupport的实例ps。 lCDu,r;\
gv}Esps
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ps.getItems()得到已分页好的结果集 8'Z#sM^E
ps.getIndexes()得到分页索引的数组 a
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ps.getTotalCount()得到总结果数 &+\J "V8
ps.getStartIndex()当前分页索引 9pKN^FX,76
ps.getNextIndex()下一页索引 bu[v[U4
ps.getPreviousIndex()上一页索引 gRS}Y8
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 \0iF <0oy
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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 b-8{bP]n
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一下代码重构了。 |*5K fxq
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我把原本我的做法也提供出来供大家讨论吧: ~ztsR;iL
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首先,为了实现分页查询,我封装了一个Page类: =7@N'xX
java代码: (+d7cln
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/*Created on 2005-4-14*/ QS:dr."k
package org.flyware.util.page; fr$E'+l)
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/** VMPBM:kG
* @author Joa 'M>QA"*48E
* /E F0~iy
*/ ]zEatY
publicclass Page { 3 f=_F
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/** imply if the page has previous page */ YvD+Lk' hm
privateboolean hasPrePage; 1zwk0={x-%
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/** imply if the page has next page */ qRkY-0vBP
privateboolean hasNextPage; I8;xuutc
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/** the number of every page */ J jRz<T;
privateint everyPage; ME"B1Se\
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<@}
/** the total page number */ wVU.j$+_#
privateint totalPage; P_S^)Yo
npC:SrI%
/** the number of current page */ &[u%ZL
privateint currentPage; hTZ&
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/** the begin index of the records by the current Bx9R!u5D
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query */
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privateint beginIndex; hKVj\88
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/** The default constructor */ g=*'kj7c3
public Page(){ P2la/jN
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} L'(ei7Z
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/** construct the page by everyPage .g/PWEr\I
* @param everyPage <'WS -P%U
* */ =PU!hZj"L
public Page(int everyPage){ u!4i+7}
this.everyPage = everyPage; &CP]+ at
} 2F5*C
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/** The whole constructor */ @8\7H'K"\
public Page(boolean hasPrePage, boolean hasNextPage, 4FwtC"G3
Tvp ~~Dk
@fz0-vT,
int everyPage, int totalPage, f/"?(7F
int currentPage, int beginIndex){ vs=8x\W
this.hasPrePage = hasPrePage; 'Cr2&
dy
this.hasNextPage = hasNextPage; -/^a2_d[
this.everyPage = everyPage; UdGa#rcNW
this.totalPage = totalPage; "XKcbdr8-
this.currentPage = currentPage; 2TQyQ%
this.beginIndex = beginIndex; 2!@ER i
} MBp,!_Q6
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/** KOv?p@d
* @return Nqy)jfyex
* Returns the beginIndex. Al93x
*/ r<)>k.]
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publicint getBeginIndex(){ FdwlRu G
return beginIndex; G q&[T:
} }Bk>'
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/** 0,{tBo
* @param beginIndex bM@8[&ta
* The beginIndex to set. %DQ!#Nl*
*/ }c]u'a!4
publicvoid setBeginIndex(int beginIndex){ \I-bZ|^
this.beginIndex = beginIndex; ta
} pw,
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/** =NNA7E7c
* @return f.e4 C,
* Returns the currentPage. x<=<Lx0B;
*/ *K#Ci1Q
publicint getCurrentPage(){ gH
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return currentPage; wJ>.I<F6B
} Bk
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/** PrQs_tNi
* @param currentPage x2M{=MExE.
* The currentPage to set. Y I?4e7Z+
*/ znq/
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publicvoid setCurrentPage(int currentPage){ Ld4Jp`Zg
this.currentPage = currentPage; IpYw<2'
} lm[LDtc
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/** 3:B4;
* @return <&m
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* Returns the everyPage. |+h8g@;Z
*/ kf-/rC)>
publicint getEveryPage(){ (i)Ed9~F"
return everyPage; ,\CG}-v@CN
} U/j+\Kc~
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/** Qh{]gw-6
* @param everyPage 69C>oX
* The everyPage to set. O8<@+xlX
*/ F7N4qq1
publicvoid setEveryPage(int everyPage){ /OsTZ"*.2/
this.everyPage = everyPage; IA(+}V
} R2B0?fu
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/** 48W-Tf6v|
* @return a";xG,U
* Returns the hasNextPage. <uL0M`u3
*/ c&>==pI]k
publicboolean getHasNextPage(){ 67b[T~92o
return hasNextPage; ;Y"*Z2U
} MoP,a9p
+jrMvk"
/** =2tl149m/z
* @param hasNextPage 6~y7A<[^
* The hasNextPage to set. m=e#1Hs
*/ h"849c;C.
publicvoid setHasNextPage(boolean hasNextPage){ bR&<vrMmrA
this.hasNextPage = hasNextPage; H>Ws)aCq
} $0wF4$)
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/** > qDHb'
* @return z ;KUIWg
* Returns the hasPrePage. [-*8S1
*/ :1(UC}v
publicboolean getHasPrePage(){ a"|\n_
return hasPrePage; =S|^pN
} \&)k{P>=
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/** EHC^ [5
* @param hasPrePage 3V2w1CERE
* The hasPrePage to set. Ze>Pg.k+
*/ YkqauyV^
publicvoid setHasPrePage(boolean hasPrePage){ M!E#T-)
this.hasPrePage = hasPrePage; Qx% ]u8s
} R404\XGL
DHO+JtO
/** /qalj\ud
* @return Returns the totalPage. !&=%#i
* zMI0W&P M
*/ B>TI dQ
publicint getTotalPage(){ \mt>R[
return totalPage; {x8UL7{
} FeM,$&G:
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/** /^>yDGT,0
* @param totalPage [
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* The totalPage to set. 9&t!U+
*/ $3C$])k
publicvoid setTotalPage(int totalPage){ \jcEEIEi
this.totalPage = totalPage; mp x/~`c
} x#
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M+N7JpR
} w'b|*_Q4Q
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6$JRV
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 tt7l%olw
D(]])4
个PageUtil,负责对Page对象进行构造: uPtHCP6
java代码: H#joc0?P
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/*Created on 2005-4-14*/ zFtw Aa =r
package org.flyware.util.page; pSq3\#Twr
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import org.apache.commons.logging.Log; :K)=Hf2y
import org.apache.commons.logging.LogFactory; \q8D7/q
F; IG@ &
/** FB0y
* @author Joa 62Ab4!
* fi[c^e+IX
*/ g8{?;
publicclass PageUtil { Wh,{|R[
3d{v5. C#X
privatestaticfinal Log logger = LogFactory.getLog _faI*OY8
9K8f
##3
(PageUtil.class); gJVakR&
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/** up~l4]b+
* Use the origin page to create a new page G~{xTpL
* @param page *6)u5
* @param totalRecords O/IW.t
* @return *XmOWV2Y_
*/ 27vLI~
publicstatic Page createPage(Page page, int m<BL/7
dm Lgt)-t
totalRecords){ {Y9m;b,X
return createPage(page.getEveryPage(), d0b--v/
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page.getCurrentPage(), totalRecords); &/J[P dSb$
} %<e\s6|P:
*|x2"?d-F:
/** qVFz-!6b
* the basic page utils not including exception %>uGzQ61
;<#fZ0(l;
handler rG"}CX`]:
* @param everyPage $}S5&
* @param currentPage HnVUG4yZTD
* @param totalRecords `5`Pv'`
* @return page #](k,% 2
*/ 181-m7W
publicstatic Page createPage(int everyPage, int
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V|{ )P@Q
currentPage, int totalRecords){ jow^~
everyPage = getEveryPage(everyPage); q+32|k>)
currentPage = getCurrentPage(currentPage); Y}"|J ~
int beginIndex = getBeginIndex(everyPage, [^W4%S
0x0.[1mB
currentPage); |rf\]3 F
int totalPage = getTotalPage(everyPage, 3vOI=ar=L~
<27B*C M
totalRecords); SGH"m/ e
boolean hasNextPage = hasNextPage(currentPage, 4aAr|!8|h!
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totalPage); u *z $ I
boolean hasPrePage = hasPrePage(currentPage); IqEY.2KN
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returnnew Page(hasPrePage, hasNextPage, \+v_6F
everyPage, totalPage, <l5{!g
currentPage, t9m:E
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beginIndex); QA.B.U7!
} P _Zf(`jJ
YFLWkdqAY
privatestaticint getEveryPage(int everyPage){ N{P (ym2yR
return everyPage == 0 ? 10 : everyPage; }tx~y-QQ
} n=t%,[Op
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privatestaticint getCurrentPage(int currentPage){ nAd
4g|
return currentPage == 0 ? 1 : currentPage; Qoq@=|7kxa
} h&yaug,.
pWps-e
privatestaticint getBeginIndex(int everyPage, int *kL1r
w6
Qkqn~>
currentPage){ ` M4;aN
return(currentPage - 1) * everyPage; d&?B/E^
} H:9(
XW
,i*^fpF`F"
privatestaticint getTotalPage(int everyPage, int s&y
MkJL9eG
totalRecords){ yYdXAenQ
int totalPage = 0; -mX
_I{BJ
)OH!<jW
if(totalRecords % everyPage == 0) {(7.X4\x
totalPage = totalRecords / everyPage; R) @k|
else s/sH",
totalPage = totalRecords / everyPage + 1 ; o?p) V^7
HE+VanY![
return totalPage; g:;v]
} f
21w`Uk48
hUA3(!0)
privatestaticboolean hasPrePage(int currentPage){ ,=o q)Fm]
return currentPage == 1 ? false : true; Q:-H UbB
} Y60ld7H
4ItXZ o
privatestaticboolean hasNextPage(int currentPage, `r>WVPS|
eIof{#
int totalPage){ R"O9~s6N
return currentPage == totalPage || totalPage == &.(ZO]
O%c6 vp7
0 ? false : true; x:l`e:`y9
} sSD(mO<(
SfL,_X]*
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} w0*6GCP
3<JZt.|
7)_0jp~2
_/E>38G]
IyP\7WZ
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。 3\D jV2t
y[r T5ed
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 =C#,aoa!
pd7FU~-
做法如下: B[$KnQM9Y
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 /;.M$}Z>`
N(1jm F
的信息,和一个结果集List: t1ZZru'r
java代码: 9wWjl}%
MQG$J!N
CSsb~/Oxu
/*Created on 2005-6-13*/ ,#WXAAmm
package com.adt.bo; rSEJ2%iF*
O]2h=M@q.
import java.util.List; ^`dp!1.+
=e._b 7P
import org.flyware.util.page.Page; <:&w/NjbI
slQKkx \Dn
/** :'!?dszS
* @author Joa /+IR^WG#C}
*/ r`7`f xe
publicclass Result { WHpbQQX
'QW 0K]il
private Page page; =lDmP|^
"+XO[WGc
private List content; )m)>k` 0
Wq>j;\3b3
/** qmL!"ZRLF
* The default constructor $x2<D :
*/ |Xu7cCh$me
public Result(){ ]\3dJ^q|%
super(); >2C;5ba
} GuS3O)6Sg
km|~DkJ\a`
/** Nm^q.)dO
* The constructor using fields 49kY]z|"w
* u>? VD%
* @param page qBwqxxTc
* @param content _* `AGda
*/ }h]:I'R!
public Result(Page page, List content){ em W#ZX
this.page = page; {< wq }~
this.content = content; Xg%zE
} 9B%"7MVn
tx.YW9xD
/** RI%l& Hm
* @return Returns the content. $jntT(V
*/ sP&E{{<QTF
publicList getContent(){ ^#Z(&/5f0
return content; +ypT"y
} "xO`&a{
1R:h$*-z
/** !nYAyjf
* @return Returns the page. U{_O=S u
*/ 5_i&}c23Vn
public Page getPage(){ -+4$W{OK*0
return page; odhgIl&u
} J{1O\i
3)eeUO+
/** EfUo<E
* @param content ilHj%h*z
* The content to set. 0-#ct1-
*/ /2U.,vw
public void setContent(List content){ I2/wu(~>
this.content = content; g 08
`=g
} >/n/n{{
LTCjw_<7
/** 8q0 .yhb
* @param page Gmc"3L
* The page to set. #"OKO6]
*/ q'@UZ$2
publicvoid setPage(Page page){ S
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this.page = page; jIW:O
} Gah e-%J
} OkQSqL
H>D_0o<#y
61KJ(
rSX3
Jv?e?U
Y#m0/1-
2. 编写业务逻辑接口,并实现它(UserManager, D"Xm9
(
xv ja
UserManagerImpl) W=b5{
6
java代码: v{jl)?`~w
Vz#cb5:g
l)|CPSN?w
/*Created on 2005-7-15*/ *oPSkEA{
package com.adt.service; *kIJv?%_}
V?gQ`( ,
import net.sf.hibernate.HibernateException; gsR"d@!
B}jZ~/D}
import org.flyware.util.page.Page; r9%W?fEBp
} 6KL
import com.adt.bo.Result; vKW%l
U8c0C/
/** vZKo&jUk
* @author Joa 9UwDa`^
*/ e9:l
publicinterface UserManager { ^\CQWgY(
}Bb(wP^B.
public Result listUser(Page page)throws x;SrJVDN
Oo0$n]*;W
HibernateException; eGE,zkj
FY
mI.*b(Irp
} dfrq8n]
=y4g. J\
0Icyi#N
_A,m@BCz
"au"\}
java代码: 6>"0H/y,
mrJQB I+
>WpPYUbH
/*Created on 2005-7-15*/ hsl8@=_ B
package com.adt.service.impl; e"bF"L
`KL`^UqR
import java.util.List; _zOzHc? Q
,4\vi|
import net.sf.hibernate.HibernateException; '`RCNk5l
_#L
IG2d
import org.flyware.util.page.Page; dRu@5
:BP
import org.flyware.util.page.PageUtil; FCIT+8K
H"-p^liw
import com.adt.bo.Result; \nJrjHA
import com.adt.dao.UserDAO; ="u(o(j"
import com.adt.exception.ObjectNotFoundException; &&m%=i.qK
import com.adt.service.UserManager; jeW0;Cz
J~
% va/x]K
/** "16==tLFE
* @author Joa U{;i 864:}
*/ tf/ f-S
publicclass UserManagerImpl implements UserManager { UA/3lH}
r^@*Cir
private UserDAO userDAO; S`R
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/** *</;:?
* @param userDAO The userDAO to set. 2x{3' ^+l
*/ xLGAP-mx]
publicvoid setUserDAO(UserDAO userDAO){ BBp
Hp
this.userDAO = userDAO; !WY@)qlf
} LAr6J
rbJ-vEzo.#
/* (non-Javadoc) 2V
* @see com.adt.service.UserManager#listUser c XY!b=9
}vm17`Gfy
(org.flyware.util.page.Page) p%G\5.GcJL
*/ SKYS6b
public Result listUser(Page page)throws }
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O|OPdD
HibernateException, ObjectNotFoundException { 8RocObY_W
int totalRecords = userDAO.getUserCount(); \V&ly/\
)
if(totalRecords == 0) )ei+ewVZ
throw new ObjectNotFoundException PvA%c<z
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("userNotExist"); lID5mg31
page = PageUtil.createPage(page, totalRecords); x^SE>dy ?z
List users = userDAO.getUserByPage(page); gz$=\=%>RL
returnnew Result(page, users); 1ltoLd\{
} ha(hG3C
9,9( mbWJv
} V^f'4*~'
ZkK +?:9
on(W^ocnD
=,(Ba'
- BocWq\
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 S4tdWA
U2K>\/ -~
询,接下来编写UserDAO的代码: |_ ;-~bmb
3. UserDAO 和 UserDAOImpl: 5[;^Em)C
java代码: SR\#>Qwx_
#_H=pNWe
t=U[ ;?
/*Created on 2005-7-15*/ 2
OGg`1XX
package com.adt.dao; O,DA{> *m
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import java.util.List; ,;{mH]"s
mT~:k}u~W
import org.flyware.util.page.Page; 7-(tTBH
@ VJr0
import net.sf.hibernate.HibernateException; 2Yyc`o0R;h
#$#{QEh0}
/** m(&ZNZK
* @author Joa w%L0mH2]ng
*/ 7IFUsli]
publicinterface UserDAO extends BaseDAO { 2sf/^XC1
0$P40 7
publicList getUserByName(String name)throws 9}": }!
)+ S" `
HibernateException; ";xG[ne$Be
:k JSu{p
publicint getUserCount()throws HibernateException; :yw0-]/DD
'1bdBx\<.
publicList getUserByPage(Page page)throws *BSL=8G{
fOrqY,P'
HibernateException; YwKY3kL
w\85D|u
} <}B]f1zX
S6Kaw
whvM^
TCB<fS~U-
x!Wl&
java代码: ydBoZ3 }
P 0,]Ud
"WK.sBFz4
/*Created on 2005-7-15*/ qk<tLvD_'
package com.adt.dao.impl; iT
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import java.util.List; O@Xl_QNxc!
t7n*kiN<q
import org.flyware.util.page.Page; Lw-)ijBW
AEEy49e
import net.sf.hibernate.HibernateException; C[&Lh_F\
import net.sf.hibernate.Query; -6Cxz./#yS
$(C71M|CT
import com.adt.dao.UserDAO; [NJ!
p2tBF98
/** $] w&`F-
* @author Joa MYjDO>(_
*/ *bwLih!}H
public class UserDAOImpl extends BaseDAOHibernateImpl U4M!RdG
OHe<U8iu%
implements UserDAO { Lv#DIQ8y
d(R3![:
/* (non-Javadoc) (\M&/X~q
* @see com.adt.dao.UserDAO#getUserByName ,7tN&R_
?6~RGg
(java.lang.String) B*,9{ g0m/
*/ !MQo=k
publicList getUserByName(String name)throws 0I079fqk<
'J+Vw9s7
HibernateException { ^d-`?zb
String querySentence = "FROM user in class ~pwp B2c
`P"-9Ue=
com.adt.po.User WHERE user.name=:name"; C{+~x@
Query query = getSession().createQuery 4B!]%Mw;c
#jK{)%}mA
(querySentence); v;{s@CM m
query.setParameter("name", name); N\ GBjr-d
return query.list(); C %y AMQ
} O:#t>
;
pSay^9ZI
/* (non-Javadoc) Ij/c@#q.
* @see com.adt.dao.UserDAO#getUserCount() ld`oIEj!P_
*/ @ttcFX1:W
publicint getUserCount()throws HibernateException { #%B1,.A
int count = 0; En-eG37l
String querySentence = "SELECT count(*) FROM rVFAwbR
8[
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user in class com.adt.po.User"; u6cWLVt
Query query = getSession().createQuery 1rT}mm/e;
(F~eknJ
(querySentence); (9@6M8A
count = ((Integer)query.iterate().next 8_m dh +
d;H1B/
()).intValue(); ;. /Tv84I^
return count; Ku 56TH!Py
} 44($a9oa2
Kl\A&O*{
/* (non-Javadoc) B1J+`R3OX
* @see com.adt.dao.UserDAO#getUserByPage Nl PP|=o
N]} L*o&
(org.flyware.util.page.Page) n"d~UV^Uw
*/ LKftNSkg"
publicList getUserByPage(Page page)throws Z'PL?;&+R
3-~_F*%ST
HibernateException { -9vAY+s.
String querySentence = "FROM user in class %\Ig{Rj;
6HFA2~A
com.adt.po.User"; o#Rao#bD:
Query query = getSession().createQuery axonqSf
XNd:x{
(querySentence); A&)P_B1|
query.setFirstResult(page.getBeginIndex()) |&h!#Q{7l
.setMaxResults(page.getEveryPage()); "EQ}xj
return query.list(); !W{|7Es?.
} cSoZq4
\d]&}`'4{f
} SQW A{f
L&q~5 9
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5/>G)&
&%C4rAd2
至此,一个完整的分页程序完成。前台的只需要调用 !V7VM_}@Y
;x|4Tm
userManager.listUser(page)即可得到一个Page对象和结果集对象 M'R^?Jjb
?(;ygjyx
的综合体,而传入的参数page对象则可以由前台传入,如果用 /QD}_lh;,
(;V]3CtU*
webwork,甚至可以直接在配置文件中指定。 K\,&wU
c|hKo[r)
下面给出一个webwork调用示例: L'z;*N3D
java代码: nNq| v=L
d cYUw]
h:Npi
`y
/*Created on 2005-6-17*/ IgR_p7['.
package com.adt.action.user; bXC;6xZV
fb&K.6"
import java.util.List; S!up2OseW
{(7C=)8):
import org.apache.commons.logging.Log; b;Q
cBGwKT
import org.apache.commons.logging.LogFactory; Y&]pC
import org.flyware.util.page.Page; +twJHf_U
I]jVnQ>&
import com.adt.bo.Result; eWW\m[k]}
import com.adt.service.UserService; 71w
import com.opensymphony.xwork.Action; j;J4]]R;o
`+k&]z$m
/** gj$gqO`B
* @author Joa ^h4Q2Mv o
*/ vEW;~FLd
publicclass ListUser implementsAction{ [[LCEw
/$/\$f$
privatestaticfinal Log logger = LogFactory.getLog htkn#s~=
~^KemwogPN
(ListUser.class); +8mfq\Y1
&HT
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private UserService userService; q}1AV7$Ai
gMFTZQsP
private Page page; hXmW,+1
Y]^[|e8
privateList users; "&77`R
C4#'`8E
/* [1G4he%
* (non-Javadoc) ,d&~#W]
* li$(oA2
* @see com.opensymphony.xwork.Action#execute() 5lVDYmh
*/ Ub4j3`
publicString execute()throwsException{ maXQG&.F
Result result = userService.listUser(page); pn{Nk1Pl
page = result.getPage(); ZMy,<wk
users = result.getContent(); f* p=]]y
return SUCCESS; X<vv:
} s-3vp
dl;^sn0s
/** 5 ,q uM"
* @return Returns the page. Aum&U){yY
*/ ,M5zhp$
public Page getPage(){ q: ?6
return page; 'HH[[9Q
} xCiY
jl$
.ie \3q)
/** _@ev(B
* @return Returns the users. TO-[6Pq#
*/ "tn]s>iAd=
publicList getUsers(){ [(F.x6z)
return users; rMdOE&5G
} %f*8JUE16
;Ze}i/l
/** )8!""n~
* @param page "6FZX~]s!
* The page to set. ~]O~a}]g(
*/ Gh>Rt=Qu%
publicvoid setPage(Page page){ F$^RM3
this.page = page; xKv\z1ra
} {M )Y6\v
f)Z$,&
/** u$X[=
* @param users a{GPAzO+
* The users to set. XBh0=E?qiS
*/ pW 2NrBq@w
publicvoid setUsers(List users){ LkK%DY
this.users = users; bzF>Efza
} ;xS@-</:
@4#q
/** [U5[;BNRD
* @param userService w/IYQC\v
* The userService to set. <v>^#/.0
*/ |D~mLs;&
publicvoid setUserService(UserService userService){ {P&{+`sov
this.userService = userService; 'JU(2mF
} A,Wwt
[Qw
} V|gW%Z,j
{E@Fk,
HIsIW%B
;wK;
]w`)"{j5m
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,
U*!q@g_
WXV (R,*Tc
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 _~/F-
N?hQ53#3
么只需要: v[{g"C
java代码: Yd'Fhvo8
~_8Dv<"a
t(AW2{%}
<?xml version="1.0"?> +pXYBwH
7Q
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ]Wr2I M
c!*yxzs\
1.0//EN" "http://www.opensymphony.com/xwork/xwork- <:/Lap#D^
`?E|frz[
1.0.dtd"> M15Ce)oB1(
DB%}@IW"
<xwork> xY4g2Q
J
=1sGT;>
<package name="user" extends="webwork- q)te/J@
cq+G 0F+H
interceptors"> <` [o|>A Z
!l NCuR/T
<!-- The default interceptor stack name 2^ uP[
jV{?.0/h|
--> nilis-Bk_
<default-interceptor-ref 3r^Ls[ey
$~7uDq
name="myDefaultWebStack"/> 2qd5iOhX+
K|L&mL&8
<action name="listUser" &pHSX
E$SYXe [,
class="com.adt.action.user.ListUser"> # dA9v7
<param |"}oGL6-
]gjQy.c|
name="page.everyPage">10</param> +pUG6.j%
<result xmVW6 ,<?
{E=BFs
name="success">/user/user_list.jsp</result> w'[JfMu P
</action> u00w'=pe)
#qLsAw--Q
</package> D/[;Y<X#V
TOT#l6yqdd
</xwork> M.FY4~
ca=sc[ $+
i%@blz:_Y
H 48YX(HI
l XpbAW
0<i8
;2KD
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 ,V^2Oa
ZLDO&}
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 :+_uyp2V
.;\uh$c
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 ($nQmr;t
^>wlj
Mz7qC3Z
`cQAO1-5
2Tp@;[!3
我写的一个用于分页的类,用了泛型了,hoho !zVjbYWY
vh"wXu
java代码: HPMj+xH
uG7?:) pxv
d\ I6Wn
package com.intokr.util; sU(<L0
hbdB67,
import java.util.List; R$h
B9BK
8vkCmV
/** bMq)[8,N
* 用于分页的类<br> 3/N~`!zeX
* 可以用于传递查询的结果也可以用于传送查询的参数<br> :F8h}\a*
* 6t\0Ui
* @version 0.01 CJjT-(a
* @author cheng w=_q<1a
*/ U?%T~!
public class Paginator<E> { D&o~4Qvc]
privateint count = 0; // 总记录数 VS\| f'E
privateint p = 1; // 页编号 ^
Paf -/
privateint num = 20; // 每页的记录数 k4d;4D?
privateList<E> results = null; // 结果 ,|g&v/WlC%
,. zHG
/** 5O(U1
*
* 结果总数 o)f$ 7.
*/ Tn"@u&P
*
publicint getCount(){ e?7y$H-
return count; 99\lZ{f(
} XU<XK9EA
.6!cHL3ln
publicvoid setCount(int count){ Aj8zFt]
this.count = count; J`4V\D}n
} Co,?<v=Ll
Dz,|sHCmk
/** 'rNLh3
* 本结果所在的页码,从1开始 ]u^ybW"
* SP\s{,'F-b
* @return Returns the pageNo. 4p7j"d5
*/ )(OGo`4Qz
publicint getP(){ O1@3V/.Wu
return p; DS+BX`i%#p
} n/Dg)n?
194n
/** LSR0yCU
* if(p<=0) p=1 ay
=B<|!
* JqUft=p5
* @param p nq,:UYNJ
*/ F~0iJnF
publicvoid setP(int p){ <isU D6TC
if(p <= 0) g[' 7 $
p = 1; s?"\+b
this.p = p; j<QK1d17
} 1Vkb}A,'
^ ;K"Y'f$
/** $VjMd f
* 每页记录数量 ^I9U<iNIL
*/ 62kA(F0e,
publicint getNum(){ <I*N=;7
return num; \irKM8]LJ
} z0x^HDAeC
vT MCZ+^g
/** ?^J%S,
* if(num<1) num=1 k%8kt4\wn6
*/ G*=&yx."E
publicvoid setNum(int num){ y<*\D_J
if(num < 1) LN)yQ-
num = 1; MskOPg
this.num = num; QE pCU)
} G O"E>FyB
&G[W$2`@
/** oB @)!'
* 获得总页数 FRL;fF
*/ c(29JZ
publicint getPageNum(){ ^$mCF%e8H
return(count - 1) / num + 1; 1;+77<