Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 V>A@Sw
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 U`<EpO{j|
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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 yKOf]m>#
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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 ?8! 4!P%n
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分页支持类: Ax0u \(p<^
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java代码: N_q7ip%z
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package com.javaeye.common.util; 9eGM6qW\_
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import java.util.List; }
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publicclass PaginationSupport { 9Wx q
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publicfinalstaticint PAGESIZE = 30; ;5" r)F+P
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privateint pageSize = PAGESIZE; [:g6gAuh,
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privateList items; +*)B;)P
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privateint totalCount; (sJ{27b_
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privateint[] indexes = newint[0]; 1x M&"p:
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privateint startIndex = 0; %Dsa
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public PaginationSupport(List items, int N1P[&lR
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totalCount){ #1u4Hi(x5
setPageSize(PAGESIZE); ,!%[CpM3
setTotalCount(totalCount); $3Wl~
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setItems(items); a/L?R
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setStartIndex(0); ?@_3B]Fs
} 39"8Nq|e
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public PaginationSupport(List items, int j*W]^uT,
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totalCount, int startIndex){ oc\rQ?
setPageSize(PAGESIZE); 1#]tCi`
setTotalCount(totalCount); y7d)[d*Mz
setItems(items); 4y
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setStartIndex(startIndex); dHf_&X2A
} rS(693kb
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public PaginationSupport(List items, int _~Lhc'^p*
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totalCount, int pageSize, int startIndex){ V%e'H>EC
setPageSize(pageSize); YaSwn3i/@S
setTotalCount(totalCount); v[m/>l2[P
setItems(items); ZwO&G\A^
setStartIndex(startIndex); n8zUL1:R
} Xb$)}n\9
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publicList getItems(){ 6<]&T lS]
return items; <MvFAuAT
} f_D1zU^
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publicvoid setItems(List items){ 6sQ"go$}
this.items = items; M9bb,`X>Q
} fB
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publicint getPageSize(){ 5IdmKP|
return pageSize; ']Y:f)i#
} YfxZ<
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publicvoid setPageSize(int pageSize){ 7OC,KgJ3
this.pageSize = pageSize; q G=`'%,m
} 2R2Z6}
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publicint getTotalCount(){ db.iMBki
return totalCount; P>4(+s
} /:yKa=$
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publicvoid setTotalCount(int totalCount){ J&8l1{gd
if(totalCount > 0){ zq{L:.#ha
this.totalCount = totalCount; p+9vSM #
int count = totalCount / .O1g'%
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pageSize; t&0n"4$d'
if(totalCount % pageSize > 0) A[oi?.D
count++; 5f}63as
indexes = newint[count]; G_42ckLq
for(int i = 0; i < count; i++){ 2+"#
indexes = pageSize * @*%5"~F
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} ;zSh9H
}else{ O;qS3
this.totalCount = 0; *QjFrw3
} )JuD !
} o5Pq>Y2T
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publicint[] getIndexes(){ wk8XD(&
return indexes; ~(I\O?k>H
} Bsz kQ>#6
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publicvoid setIndexes(int[] indexes){ #<v3G)|aS
this.indexes = indexes; RMLs(?e
} DJrA@hm/Y
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publicint getStartIndex(){ x]y~KbdeB
return startIndex; `n5)oU2q
} ZL1[Khr,s
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publicvoid setStartIndex(int startIndex){ "V?U^L>SF
if(totalCount <= 0) \i`/k(
this.startIndex = 0; q'K=Ly+
elseif(startIndex >= totalCount) r%_)7Wk*
this.startIndex = indexes ZZl)p\r
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[indexes.length - 1]; JRU)AMMU&
elseif(startIndex < 0) tOp>OoD
this.startIndex = 0; <5C3c&sds
else{ 4\Q ?4ZX
this.startIndex = indexes ']}ZI 8
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[startIndex / pageSize]; $+7MY-9T
} T-|z18|!
} Zf?>:P
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publicint getNextIndex(){ BS+N
int nextIndex = getStartIndex() + ;znIY&Z
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pageSize; --
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if(nextIndex >= totalCount) /o8h1L=
return getStartIndex(); lm]4zs /A
else @uT\.W:Q2
return nextIndex; E(TL+o
} f&{2G2O%
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publicint getPreviousIndex(){ 0QEVL6gw
int previousIndex = getStartIndex() - U.?,vw'aai
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pageSize; =AZ>2P
if(previousIndex < 0) 9{xP~0g
return0; ;'R{b$B;|
else u]"oGJj1
return previousIndex; JsVW:8QO~
} PN0:,.4
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} qBKIl=
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抽象业务类 i(L;1 `
java代码: obaJT"1
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/** V\)@Yk2
* Created on 2005-7-12 6^UeEmjc
*/ vPSH
package com.javaeye.common.business; 0'z$"(6D
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import java.io.Serializable; )Hl;9
import java.util.List; (j}"1
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import org.hibernate.Criteria; 0I~xD9l9
import org.hibernate.HibernateException; x:@Ht TX
import org.hibernate.Session; F/&Z1G.
import org.hibernate.criterion.DetachedCriteria; ldi'@^
import org.hibernate.criterion.Projections; y=5s~7]
import R}>Gk
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org.springframework.orm.hibernate3.HibernateCallback; N7}.9%EV
import N<Ti[Q]G
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org.springframework.orm.hibernate3.support.HibernateDaoS tY%c-m
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upport; f:Ju20D
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import com.javaeye.common.util.PaginationSupport; [S-NGip
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public abstract class AbstractManager extends GwW!Q|tVz=
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HibernateDaoSupport { YX!%R]c%
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privateboolean cacheQueries = false; 1&Nk
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privateString queryCacheRegion; f>-OwL($P
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publicvoid setCacheQueries(boolean lj'c0k8
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cacheQueries){ )#IiHBF
this.cacheQueries = cacheQueries; xREqcH,vU
} @6}c\z@AxM
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publicvoid setQueryCacheRegion(String |UBR8
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queryCacheRegion){ &Q(Q/]U~
this.queryCacheRegion = w*$nG$
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queryCacheRegion; 5pE[}@-c9
} T3%yV*F,
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publicvoid save(finalObject entity){ G5bi,^G7
getHibernateTemplate().save(entity); qmtVk
} B5zu?AG
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publicvoid persist(finalObject entity){ ^e<0-uM"s
getHibernateTemplate().save(entity); lNls8@
} L?4c8!Q
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publicvoid update(finalObject entity){ gWv/3hWWB
getHibernateTemplate().update(entity); !T6oD]x3
} p,$1%/m
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publicvoid delete(finalObject entity){ :$dGcX}
getHibernateTemplate().delete(entity); E3_EXz9h
} j?[fpN$
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publicObject load(finalClass entity, DJ[U^dWRn
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finalSerializable id){ ^HX={(ddK
return getHibernateTemplate().load >2vl & (
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(entity, id); 6=MejT
} P[%
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publicObject get(finalClass entity, n"(n*Hf7b
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finalSerializable id){ +, p
return getHibernateTemplate().get L8TT54fM
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(entity, id); 9 qqy( H
} 'O
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publicList findAll(finalClass entity){ ~EpMO]I
return getHibernateTemplate().find("from E9!IGci
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" + entity.getName()); ? R;5ErZ
} #Z98D9Pv`o
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publicList findByNamedQuery(finalString TM[Z~n(wt
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namedQuery){ o8H<{D13
return getHibernateTemplate O]4!U#A
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().findByNamedQuery(namedQuery); FavU"QU&|
} n|yl3v
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publicList findByNamedQuery(finalString query, 1;080|,s
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finalObject parameter){ %pt ul_(s'
return getHibernateTemplate ubj
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().findByNamedQuery(query, parameter); *x)WF;(]g
} C W7E2
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publicList findByNamedQuery(finalString query, lWd)(9Kj
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finalObject[] parameters){ DTlM}
return getHibernateTemplate L7wl3zG
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().findByNamedQuery(query, parameters); $_@~t$
} &s\$&%|
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publicList find(finalString query){ !b7]n-1zs
return getHibernateTemplate().find ` {k>I^Pg
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(query); "z=A=~~<{
} p! zC
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publicList find(finalString query, finalObject 43A6B
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parameter){ 4ME8NEE
return getHibernateTemplate().find C!Y|k.`p
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(query, parameter); -]+XTsL
} 7h&$^
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public PaginationSupport findPageByCriteria .gG<08Z
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(final DetachedCriteria detachedCriteria){ slOki|p;
return findPageByCriteria %+Z0$Q
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); eW1$;.^
} {5#P1jlT
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public PaginationSupport findPageByCriteria -EF(J
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(final DetachedCriteria detachedCriteria, finalint 'R*xg2!i
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startIndex){ =c(_$|0
return findPageByCriteria 4CW/
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(detachedCriteria, PaginationSupport.PAGESIZE, J=
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startIndex); *O)_D
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} Y
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public PaginationSupport findPageByCriteria LJc
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(final DetachedCriteria detachedCriteria, finalint ed'}ReLK
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pageSize, `JG~%0Z?}
finalint startIndex){ Ke&lGf"5
return(PaginationSupport) mB"zyL-
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getHibernateTemplate().execute(new HibernateCallback(){ ,b-wo
publicObject doInHibernate k]qZOO}
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(Session session)throws HibernateException { 5caYA&R
Criteria criteria = N>/*)Frt
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detachedCriteria.getExecutableCriteria(session); #Vs/1y`()
int totalCount = o*qEAy?
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((Integer) criteria.setProjection(Projections.rowCount r[TS#hQ
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()).uniqueResult()).intValue(); |Mo# +{~c
criteria.setProjection w_KGn17
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(null); q)G*"
List items = KjZ^\lq'
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criteria.setFirstResult(startIndex).setMaxResults `eND3c
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(pageSize).list(); bjm`u3
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PaginationSupport ps = \#LKsQa
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new PaginationSupport(items, totalCount, pageSize, <j ;HRm
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startIndex); ,H22;UV9
return ps; vEtogkFA"
} qt^%jIv
}, true); $C9<{zX
} +A~lPXAXW
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public List findAllByCriteria(final 3 [SN[faS
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DetachedCriteria detachedCriteria){ UM|GX
return(List) getHibernateTemplate >B8)Wb:
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().execute(new HibernateCallback(){ f#eTi&w
publicObject doInHibernate wS``Q8K+dM
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(Session session)throws HibernateException { l2VO=RDiW
Criteria criteria = ;cp-jY_U
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detachedCriteria.getExecutableCriteria(session); `Jm{K*&8Q
return criteria.list(); oxO}m7ULH
} :e+GtN?
}, true); e!tgWYN
} &Eidc .
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public int getCountByCriteria(final B|:{.U@ne
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DetachedCriteria detachedCriteria){ U|{WtuR
Integer count = (Integer) v bDw2
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getHibernateTemplate().execute(new HibernateCallback(){ D1o 8Wo
publicObject doInHibernate ni2H~{]z
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(Session session)throws HibernateException { ]3d&S5zU
Criteria criteria = s$H5W`3
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detachedCriteria.getExecutableCriteria(session); Mh~T.;f.qq
return V9Au\
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criteria.setProjection(Projections.rowCount `(Q58wR}
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()).uniqueResult(); 7MoO2
} +QldZba
}, true); {H])Fob
return count.intValue(); PDD` eK}Fj
} *k+QX
} :\4O9f*5+
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用户在web层构造查询条件detachedCriteria,和可选的 yt!K|g
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 A8Jbl^7E+
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PaginationSupport的实例ps。 3g-}k
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ps.getItems()得到已分页好的结果集 h$ZF[Xbfe
ps.getIndexes()得到分页索引的数组 1"v;w!uh
ps.getTotalCount()得到总结果数 1d\K{ 7i#
ps.getStartIndex()当前分页索引 }}_WZ},h
ps.getNextIndex()下一页索引 B5I(ai7<M
ps.getPreviousIndex()上一页索引 ;H:qDBH
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 .zegG=q
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 E+~~d6nB
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一下代码重构了。 NoKYHN^*w
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我把原本我的做法也提供出来供大家讨论吧: (qPZEZKx
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首先,为了实现分页查询,我封装了一个Page类: <78>6u/W%
java代码: !2{MWj
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/*Created on 2005-4-14*/ Qz$.t>@V=
package org.flyware.util.page; UI8M<
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/** b%)a5H(
* @author Joa C
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* {ld([
*/ .S5&MNE
publicclass Page { Nm;ka&'
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/** imply if the page has previous page */ MaMs(
privateboolean hasPrePage; C}00S{nAZ
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/** imply if the page has next page */ Eydk645:3
privateboolean hasNextPage; lcUL7
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/** the number of every page */ #vDe/o+=
privateint everyPage; Q7DkhKT
CX1'B0=\r
/** the total page number */ 'E7|L@X"r
privateint totalPage; |20p#]0E+
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/** the number of current page */ Sk1yend4
privateint currentPage; PMTyiwlm
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/** the begin index of the records by the current wEkW=
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query */ (JF\%Yj/
privateint beginIndex; 7vHU49DV
= j}00,WH
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/** The default constructor */ FD`V39##
public Page(){ IzL
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} Z#Zk)
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/** construct the page by everyPage TI*uNS;-
* @param everyPage UnO -?
* */ 1$
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public Page(int everyPage){ r-!8in2
this.everyPage = everyPage; e8gD(T
} f|<
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/** The whole constructor */ h\20
public Page(boolean hasPrePage, boolean hasNextPage, M&>Z[o
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int everyPage, int totalPage, E8V,".!+E
int currentPage, int beginIndex){ g!K(xhEO
this.hasPrePage = hasPrePage; Y]Xal
this.hasNextPage = hasNextPage; )9PQj
this.everyPage = everyPage; Uh9$e
this.totalPage = totalPage; 2} T"|56
this.currentPage = currentPage; r?Z8_5Y
this.beginIndex = beginIndex; &]ImO
RN
} $MP'j9-S?
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/** &1VC0"YJWy
* @return >Vg<J~[g
* Returns the beginIndex. !J+5l&
*/ _$F I>
publicint getBeginIndex(){ q'1rSK
return beginIndex; EmH2 Dbw
} un..UU4
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/** p'_*>%4~
* @param beginIndex .=K@M"5&
* The beginIndex to set. G8<,\mg+
*/ /r]IY.
publicvoid setBeginIndex(int beginIndex){ WAob"`8]
this.beginIndex = beginIndex; 5$jKw\FF=
} &|',o ?'F
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/** JA1(yt
* @return 4wK!)Pwq
* Returns the currentPage. WF:i}+g+^
*/ G-T:7
publicint getCurrentPage(){ ,!Q2^R
return currentPage; CM~)\prks
} 0A|.ch
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/** PCD1I98
* @param currentPage Pirc49c
* The currentPage to set. 4m%_#J{
*/ pYVQ-r%QF
publicvoid setCurrentPage(int currentPage){ ku?i[Th
this.currentPage = currentPage; Q;`#ujxL
} CFn!P;.!
7]G3yt->
/** X_"TG;*$
* @return ]3C7guWz
* Returns the everyPage. hPH=.rX
*/ UX(#C,qgG
publicint getEveryPage(){ 9r8*'.K`Z
return everyPage; Q7f\ 5QjT
} gP)g_K(e
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/** K~C*4H:9
* @param everyPage :3u>%
* The everyPage to set. Ga$+x++'*
*/ / 1g_Uv;
publicvoid setEveryPage(int everyPage){ >Ei_##
this.everyPage = everyPage; 4Yx?75/
} @R>J\>
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/** rT5dv3^MW!
* @return HPm12&8,
* Returns the hasNextPage. C:z K{+
*/ FhS:.
publicboolean getHasNextPage(){ ?MyXii<a
return hasNextPage; e=TB/W_
} b6Dve]
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/** =A04E
* @param hasNextPage
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* The hasNextPage to set. (|"KsGl
*/ b`fPP{mG
publicvoid setHasNextPage(boolean hasNextPage){ X>=`{JS1
this.hasNextPage = hasNextPage; _KC()OIeC
} B&`#`]
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/** i5q
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* @return wjQu3 ,Cj
* Returns the hasPrePage. hH|3s-o
*/ $_% a=0
publicboolean getHasPrePage(){ ,;hIyT
return hasPrePage; 6:#zlKYJ
} i4&"-ujrm
G2zfdgW${/
/** @9-z8PyF
* @param hasPrePage !A, ]
* The hasPrePage to set. +A3@{2
*/ ON\_9\kv
publicvoid setHasPrePage(boolean hasPrePage){ x{j|Tf3,G
this.hasPrePage = hasPrePage; AWc7TW
} YrL:!\p.
@|idlIey
/** {-09,Q4[&
* @return Returns the totalPage. IXe[JL:
* j"9bt GX
*/ nYLq%7}k
publicint getTotalPage(){ u4, p.mZtb
return totalPage; kW3V"twx
} #\_N-bVu
a4Fe MCvV9
/** S{7A3
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* @param totalPage k$j>_U? P
* The totalPage to set. 6DD"Asi+
*/ nM>oG'm[n
publicvoid setTotalPage(int totalPage){ :]v%6i.
this.totalPage = totalPage; sjvlnnO
} NVAt-u0LB
yL7D;<!S&
} u`O
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L
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z}&?^YU*)`
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 L#1YR}m
wKIQK!B)mF
个PageUtil,负责对Page对象进行构造: s=h
java代码: '%vb&a!.6
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/*Created on 2005-4-14*/ 3pl/kT.\
package org.flyware.util.page; P4-`<i]!S
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import org.apache.commons.logging.Log; N0,wT6.
import org.apache.commons.logging.LogFactory; */;[ -9
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/**
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* @author Joa zxTcjC)y
*
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*/ y-w=4_W
publicclass PageUtil { !`LaX!bmp
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privatestaticfinal Log logger = LogFactory.getLog L}T:Y).
f 0A0uU8y
(PageUtil.class); R @N
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/** Ne!F
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* Use the origin page to create a new page mtSOygd
* @param page d!mtSOh
* @param totalRecords ms@*JCL!t
* @return ^V#9{)B
*/ FAkjFgUJp
publicstatic Page createPage(Page page, int "7mYs)=
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totalRecords){ GVP"~I~/:
return createPage(page.getEveryPage(), ]r8t^bqe
* $~H=4t
page.getCurrentPage(), totalRecords); N}HQvlLkF9
} $w4%JBZr
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/** W ZdEfY{
* the basic page utils not including exception %5Hsd
\
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handler #9M6 q
* @param everyPage ^x-vOGlR
* @param currentPage uu@Y]0-
* @param totalRecords B8;jRY
* @return page PY-
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*/ /n;Ll](ri
publicstatic Page createPage(int everyPage, int :34]}`-
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currentPage, int totalRecords){ FKRO0%M4}Z
everyPage = getEveryPage(everyPage); #}*w &y
currentPage = getCurrentPage(currentPage); |h$*z9bsf
int beginIndex = getBeginIndex(everyPage, KE! aa&g
qkVGa%^
currentPage); PLD6Ug
int totalPage = getTotalPage(everyPage, QWz5iM
a$H*C(wL
totalRecords); D;VQoO
boolean hasNextPage = hasNextPage(currentPage, &/R`\(hEA
- e0C
Bp
totalPage); &D0suK#
boolean hasPrePage = hasPrePage(currentPage); ?0
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,WSK
'
returnnew Page(hasPrePage, hasNextPage, r!:W-Y%
everyPage, totalPage, 8|*#r[x
currentPage, Z^5j.d{e$
HxCq6Y_m<
beginIndex); G8b/eWtP
} A[)od
RP 'VEJ
privatestaticint getEveryPage(int everyPage){ IA_>x9 (~
return everyPage == 0 ? 10 : everyPage; 6$c,#%Jt*
} 7ADh
e&%m[:W:<
privatestaticint getCurrentPage(int currentPage){ ^PA[fL"
return currentPage == 0 ? 1 : currentPage; o>*vG
} .#0),JJZ[
FYq]-k{\
privatestaticint getBeginIndex(int everyPage, int 9ZFvN*Zf'
oE@{h$=
currentPage){ tgoOzk^
return(currentPage - 1) * everyPage; AE0d0Y~9
} 'NCxVbyYD
yZkHBG4
privatestaticint getTotalPage(int everyPage, int ^T*^L=L_(
x}Qet4vV
totalRecords){ dJID '2a
int totalPage = 0; Xvu|ss
y
Nb&;E7 H
if(totalRecords % everyPage == 0) /xf4*zr
totalPage = totalRecords / everyPage; :a$ZYyD
else /!J1}S
totalPage = totalRecords / everyPage + 1 ; vl59|W6
{T|sU\| Q
return totalPage; ZfalB
} [GKSQt{)
Cx$C+
privatestaticboolean hasPrePage(int currentPage){ v\7k
return currentPage == 1 ? false : true; s33< }O0
} rK&ofc]f$
$jMU|{
privatestaticboolean hasNextPage(int currentPage, .Rl58]x~
8was/^9;
int totalPage){ t95hI DtD
return currentPage == totalPage || totalPage == ^,S\-Uy9
R7aS{8nn
0 ? false : true; "j|}-a
} +LddW0h+=8
q)JG_Y.p
K^z-G=|N
} qT]Bl+h2
iw1((&^)"
o%#Z
K0B
J
N}{CL(xi
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 /E>z8J$
,Nl]rmI
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 aIaydu+ \
,])@?TJb@
做法如下: J]uYXsC
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 9D74/3b*
^aVoH/q*C
的信息,和一个结果集List: Y68`B"3
java代码: 9HMW!DSK`
<}'hkEh{d=
pKK&+umg
/*Created on 2005-6-13*/ d5<@WI:wz
package com.adt.bo; *UVjN_na5
7O5`&Z'-
import java.util.List; T=7V+
EN@LB2
import org.flyware.util.page.Page; :H[E
W3Q
Ycb<'M*jE
/** TSu^.K
* @author Joa 4f,D3e%T|
*/ ]e+IaZ[Wo
publicclass Result { v8g3]MVj3
pJ7wd~wF*
private Page page; B.fLgQK0
FxOhF03\=[
private List content; q|m8G
9R.IYnq
/** (?-5p;
* The default constructor wqo2iRql
*/ 9/C0DDb
public Result(){ j}YZl@dYV
super(); @(.?e<
} -F,o@5W>Y
U,/NygB~
/** R`=IYnoOA
* The constructor using fields <x@\3{{U
* p-V#nPb
* @param page D[{p~x^
* @param content V M[9!:
*/ K8*QS_*
public Result(Page page, List content){ S8j;oJ2d
this.page = page; u&l2s&i
this.content = content; fX G+88:2
} M%4o0k]E,s
><iE VrpN
/** #I9|>XE1
* @return Returns the content. DoWY*2E
*/ bTC2Ya
publicList getContent(){ )>at]mH
return content; BXueOvO8
} @Zd+XWFw
}4xxge?r
/** THQW8 V
* @return Returns the page. oMda)5 &
*/ {B|U8j[
public Page getPage(){ g=; rM8W
return page; j-$aa;
} HCQv"i}-
Rf2/[
/** <Xw 6m$fr:
* @param content ;}K1c+m!5V
* The content to set. aq"E@fb
*/ rBs7,h
public void setContent(List content){ y5?T`ts,#
this.content = content; GSV,
} #Q6wv/"Ub
S6}_Z
/** S}e*~^1J
* @param page Wf_aEW&n
* The page to set. fT._Os?i
*/ ,IuO;UV#)
publicvoid setPage(Page page){ P>euUVMPz4
this.page = page; 9In&vF7$
} H_;Dq*
} 'N=' B<^;%
hX)r%v:
=pWpHbB.
&{&lCBN
3]'=s>UO>^
2. 编写业务逻辑接口,并实现它(UserManager, ni@D7:h
v)N6ZOj*C
UserManagerImpl) i#lvt#2J0
java代码: PGT!HdX#{
I>/`W
O~d!*A
/*Created on 2005-7-15*/ psRm*,*O
package com.adt.service; y5a^xRDw
EN.yU!N.4
import net.sf.hibernate.HibernateException; lGG1d
w,8 M
import org.flyware.util.page.Page; ] >ipC,v
Djf2ir'
import com.adt.bo.Result; dG7sY
O@U
~\<ZWU<BE
/** xx;'WL,g
* @author Joa 6z%3l7#7Yi
*/ %n}fkj'
publicinterface UserManager { {KwLcSn
/7S]%UY
public Result listUser(Page page)throws +KFK..
rA*,)I_v@
HibernateException; AG}'
W
ZM;EjS1
} [$[t.m
ieBW 0eMi
(/"T=`3t
.[cT3l/t
UMhM8m!=o
java代码: &[*<>
.E;6Xx_+r
od^ha
/*Created on 2005-7-15*/ ie.cTTOI
package com.adt.service.impl; gK)B3dH*&
tY# F8a&
import java.util.List; Qg6m
A9l^S|r
import net.sf.hibernate.HibernateException;
}f&7<E
)CR8-z1`
import org.flyware.util.page.Page; t1C{
import org.flyware.util.page.PageUtil; 1b|<
#s
yP=
import com.adt.bo.Result; HqYaQ~Dth
import com.adt.dao.UserDAO; ;o^m"I\y
import com.adt.exception.ObjectNotFoundException; G#@<bg3
import com.adt.service.UserManager; ;k/0N~
P\zi:]h[Gh
/** n+uq|sYVa
* @author Joa )1x333.[c
*/ (OG@]|-
publicclass UserManagerImpl implements UserManager { /-|xxy
$ @1&G~x
private UserDAO userDAO; >MQW{^
-IX;r1UD
/** MeplM$9
* @param userDAO The userDAO to set. {{EQM
+
*/ RuRJ jcnY
publicvoid setUserDAO(UserDAO userDAO){ gu:..'V
this.userDAO = userDAO; ;'o>6I7Ph
} ?N|PgNu X
@XIwp2A{+
/* (non-Javadoc) sL/Lw
WH
* @see com.adt.service.UserManager#listUser yp*kMC,3
?,%N?
(org.flyware.util.page.Page) &R^mpV5
*/ _R-#I
public Result listUser(Page page)throws HKxrBQr78
UVI=&y]c,p
HibernateException, ObjectNotFoundException { "R9kF-
int totalRecords = userDAO.getUserCount(); H`io|~Q
if(totalRecords == 0) fZ
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throw new ObjectNotFoundException HPCA,*YR`
JK_$A;Q
("userNotExist"); &P+cTN9)
page = PageUtil.createPage(page, totalRecords); 4P:vo $Cy
List users = userDAO.getUserByPage(page); hR`dRbBi%
returnnew Result(page, users); R>0ta
Q
} ?1412Tq5
+M.|D,wg2
} *@BBlkcx
(Q&z1XK3
F
H%yyT
V&}Z# 9Dx
9n%W-R.
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ljf9L:L
]g)%yuox9F
询,接下来编写UserDAO的代码: ovfw _
3. UserDAO 和 UserDAOImpl: \@F{Q-
java代码: X|q0m3jt
zYs? w=
GYs4#40
/*Created on 2005-7-15*/ 4%6Q+LS']Q
package com.adt.dao; 1bDc ct
]D]K_`!K
import java.util.List; eb8_guZ
Q@j:b]Y9
import org.flyware.util.page.Page; q{5Vq_s\
OB^
import net.sf.hibernate.HibernateException; &a(w0<
x
p$0J<2
/** ^IId
=V=2
* @author Joa Fwqv1+
*/ Rd!.8K[
publicinterface UserDAO extends BaseDAO { @v'<~9vG
%FRkvqV*
publicList getUserByName(String name)throws dW5z0VuB$/
i)p__Is
HibernateException; ;s!H
07MLK8jS
publicint getUserCount()throws HibernateException; #nxx\,i>
u4nXK
<KL|
publicList getUserByPage(Page page)throws xAO]u[J
'qD9kJ`
HibernateException; He@= bLLa
ZEMo`O
} ?@,:\ ,G
z&:[.B
u,]yd*
df)1}/*L
gbh:Y}_FU
java代码: EtcamI*`
Xg)yz~Ug
}B.C#Y$@
/*Created on 2005-7-15*/ j)0R*_-B[
package com.adt.dao.impl; Nl8Cctrf
4NzHzn
import java.util.List; t.TQ@c+,J
oe<Y,%u"6
import org.flyware.util.page.Page; hh{liS% 10
d"cfSH;h
import net.sf.hibernate.HibernateException; (M=Br
import net.sf.hibernate.Query; uXC?fMWp.
JQCwI`%i
import com.adt.dao.UserDAO;
zhe5i;M
&sWyh[`P
/** kr/h^e
* @author Joa loB/w{r*x
*/ WI9.?(5q
public class UserDAOImpl extends BaseDAOHibernateImpl ,jWd?-NH
X>4`{x `
implements UserDAO { 9..k/cH
a]k&$
/* (non-Javadoc) Z8@]e}n
* @see com.adt.dao.UserDAO#getUserByName |{nI.>
LKZI@i)
(java.lang.String) }X?*o`sW
*/ WWLVy(
publicList getUserByName(String name)throws _7<U[63
:6 fQE#(s&
HibernateException { QUDVsN#
String querySentence = "FROM user in class Ss:,#|
+g[B &A!d+
com.adt.po.User WHERE user.name=:name"; K_aN7?#.v`
Query query = getSession().createQuery ._3NqE;
.R'i=D`Pz
(querySentence);
i=D,T[|>a
query.setParameter("name", name); yM2&cMHH~
return query.list(); l_%~X9"
} $^!w`>0C
cn0Fz"d
/* (non-Javadoc) "m3Y))a
* @see com.adt.dao.UserDAO#getUserCount() r;C\eN
*/ x(`$D
publicint getUserCount()throws HibernateException { rZv+K/6*M
int count = 0; yDC97#%3u
String querySentence = "SELECT count(*) FROM ,Aii>D]
;cr6Xop#?
user in class com.adt.po.User"; c
v
9
6F
Query query = getSession().createQuery >N
J$ac
WdAGZUp
(querySentence); SS~Q ;9o
count = ((Integer)query.iterate().next $%JyM
bAiw]xi
()).intValue(); \7/_+)0}'
return count; G= cxc_9
} {1%ZyY
>B
/* (non-Javadoc) d@tr]v5 B
* @see com.adt.dao.UserDAO#getUserByPage `[CJtd2\
<3}l8Z
(org.flyware.util.page.Page) AF$ o>f
*/ ^Q>*f/.KN
publicList getUserByPage(Page page)throws JWL J<z
-/%jeDKp
HibernateException { Jf$wBPg
String querySentence = "FROM user in class pG6-.F;
5XI*I(.%/
com.adt.po.User"; A.O~'')X
Query query = getSession().createQuery ^mpB\D)q
@UX@puK`/
(querySentence); ;vdgF
query.setFirstResult(page.getBeginIndex()) oDUMoX%4s
.setMaxResults(page.getEveryPage()); \T9UbkR
return query.list(); \<B6>
} WZ&@
J B
SZ{cno1`
} H>f{3S-%
)yW_O:
hhAC@EGG
M[u3]dN
4d
G-
至此,一个完整的分页程序完成。前台的只需要调用 "S`wwl
ZPao*2xz
userManager.listUser(page)即可得到一个Page对象和结果集对象 MPn>&28"|K
|:+pPh!-
的综合体,而传入的参数page对象则可以由前台传入,如果用 i(;-n_:,`
x
5Dt5Yp"o
webwork,甚至可以直接在配置文件中指定。 {Ch"zuPX
`YNC_r#tG
下面给出一个webwork调用示例: p0y?GNQ
java代码: f+Me dc~
~^~RltY
[V,
;X
/*Created on 2005-6-17*/ .oj" ru
package com.adt.action.user; T1HiHvJ
&6=ZT:.6Te
import java.util.List; #0^3Wm`X;
D{c>i`\G
import org.apache.commons.logging.Log; BJxmW's/
import org.apache.commons.logging.LogFactory; &W+G{W{3
import org.flyware.util.page.Page; G!Oq>7
hX| UE
import com.adt.bo.Result; V)QR!4De
import com.adt.service.UserService; |~LjH |*M
import com.opensymphony.xwork.Action; BC{J3<0bf@
5qQ(V)ah
/** \Ntdl:fSw
* @author Joa }|"*"kxi!
*/ `OReSg
2
publicclass ListUser implementsAction{ %GCd?cFF
D.R|HqZ
privatestaticfinal Log logger = LogFactory.getLog y'|W['
e=;@L3f
(ListUser.class); UN?T}p-
oF
C%?D E@k
private UserService userService; {_ho!OS>
{C0^D*U:
private Page page;
"rDzrz
}_ :#fE
privateList users; =tRe3o0(
-sH.yAvC6
/* k,iV$,[TF
* (non-Javadoc) Ox*T:5
* 40d9/$uzh
* @see com.opensymphony.xwork.Action#execute() I u~aTgHX%
*/ Doc'7P
publicString execute()throwsException{ 'A(-MTd%
Result result = userService.listUser(page); \
Q8q9|g?]
page = result.getPage(); p
z+}7
users = result.getContent(); 4i\aW:_'i
return SUCCESS; ^=Tu>{uD
} h8= MVh(I
<T.#A8c
/** C\2 >7
* @return Returns the page. UFAMbI
*/ hPi
:31-0
public Page getPage(){ 0R 5^p
return page; ID).*@(I"
} l)PFzIz=V
vua1iN1
/** ah"MzU)
* @return Returns the users. 9Bvn>+_K
*/ C`~4q<W'
publicList getUsers(){ F;&fx(
return users; 9k+&fyy
} (T#(A4:6S
vl{_M*w
;
/** m57tOX
* @param page S}p&\w H
* The page to set. yZ~eLWz
*/ `_g?y)
publicvoid setPage(Page page){ J%-lw{FC
this.page = page;
vH?+JN"A
} {{[jC"4AY
c>WpO Z,
/** &0
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* @param users ZJI1NCBZ
* The users to set. Up/u|A$0V
*/ 07LL)v~
publicvoid setUsers(List users){ W/ZahPPq
this.users = users; V=zM5 MH2
} -2jBs-z
)4F/T, {;m
/** ]T3BDgu%&
* @param userService A]O5+"mc
* The userService to set. Yx}"> ;\
*/ ?(NT!es
publicvoid setUserService(UserService userService){ 5IE+M
this.userService = userService; uM#U!
} J,0WQQnb
} q%kj[ZOY$]
7MuK/q.
o!l3.5m2d
Xm^h5jAr
_Dcc<-.
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, sg6w7fp>
oA3W
{
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 k"^t?\Q%vI
\`Ph=lJO
么只需要: D@rn@N
java代码: ! N"L`RWD
g"dZB2`C
\l=KWa 3Q
<?xml version="1.0"?> Q1ABnacR
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork }2BH_
2
[>M*_1F
1.0//EN" "http://www.opensymphony.com/xwork/xwork- [,o5QH\Etq
mb~=Xyk&
1.0.dtd"> z^a!C#IX
),y!<\oQ
<xwork> rm)SfT<
Nvx)H(8F
<package name="user" extends="webwork- mcz(,u}
#-gGsj;F
interceptors"> =4M.QA@lI!
n2y/zP>TC
<!-- The default interceptor stack name Z*vpQBbu
S`2mtg
--> /,uSCITD
<default-interceptor-ref Gkodk[VuLs
pT
ocqJ22
name="myDefaultWebStack"/> ;( Ajf.i
gGI#QPT`X
<action name="listUser" @^:7UI_
Z*)y.i `
class="com.adt.action.user.ListUser"> _sf#J|kQ
<param ~g
K-5}%!
7k`*u) Q
name="page.everyPage">10</param> u.pKK
<result AK~`pq[.
SP
D207
name="success">/user/user_list.jsp</result> 9HJ'p:{)
</action> &8X
.!r`f
n$OE~YwP{
</package> hk5E=t~&
O'!r]0Q
</xwork> "3Xv%U9@
<