Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 iJ ($YvF4
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 nXaC3W:"
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 \S"is z
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 j%Y#(Q>
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分页支持类: ]Oe2JfJwx
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java代码: t=BUN
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package com.javaeye.common.util; sv2A-Dld
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import java.util.List; 2A']yD
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publicclass PaginationSupport { a1g,@0s
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publicfinalstaticint PAGESIZE = 30; e+=y*OmQ
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privateint pageSize = PAGESIZE; t*=CZE -
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privateList items; `jDTzhO~
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privateint totalCount; %p Ynnfr
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privateint[] indexes = newint[0]; o5u3Fjz3
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privateint startIndex = 0; -{KQr1{5UM
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public PaginationSupport(List items, int Bm:98? [
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totalCount){ ,[N%Q#
setPageSize(PAGESIZE); kC:uG0sW
setTotalCount(totalCount); TeMHm?1^
setItems(items); b}2ED9HG\
setStartIndex(0); S%$ }(
} JL`-0P<M
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public PaginationSupport(List items, int aKJwofD
@CNi{. RX
totalCount, int startIndex){ \J4L:.`qS
setPageSize(PAGESIZE); t DO=P
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setTotalCount(totalCount); pg6cF
setItems(items); S~<$Hy*kh
setStartIndex(startIndex); aJSO4W)P
} cA&9e<
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public PaginationSupport(List items, int Ij 79~pn
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totalCount, int pageSize, int startIndex){ -fM1nH&
setPageSize(pageSize); 2ElJbN#
setTotalCount(totalCount); ~b(i&DVK
setItems(items); @tF\p
setStartIndex(startIndex); 2my_ ;!6T[
} 8mCxn@yV
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publicList getItems(){ .14~J6
return items; #F:p-nOq
} zp6C3RG(
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publicvoid setItems(List items){ 32(^Te]:
this.items = items; oF vfCrd
} ]v?@g:iE
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publicint getPageSize(){ Juo^ ,
return pageSize; $&Gu)4'+
} l\f*d6o
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publicvoid setPageSize(int pageSize){ ov|d^)'
this.pageSize = pageSize; {5A2&
} LmRy1T,act
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publicint getTotalCount(){ @MoKWfc
return totalCount; B[qzUD*P_n
} WEAT01
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publicvoid setTotalCount(int totalCount){ M|VyV(f
if(totalCount > 0){ HsxVZ.dS
this.totalCount = totalCount; GmK^}=frj
int count = totalCount / H!c@klD
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pageSize; } FE>|1
if(totalCount % pageSize > 0) k3~}7]O)
count++; pD(j'[
indexes = newint[count]; Fzm*Pz3
for(int i = 0; i < count; i++){ FOb0uj=(v
indexes = pageSize * c7 ?_46J
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} 9q)Kfz
}else{ N>Xo_-QCY
this.totalCount = 0; \TIT:1
} j
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} ?}qttj
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publicint[] getIndexes(){ Ig$(3p
return indexes; ?llXd4
} i|c'Lbre`
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publicvoid setIndexes(int[] indexes){ Yy5h"r
this.indexes = indexes; 57aXQ8u{
} K)6rY(x
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publicint getStartIndex(){ v0ujdp,B
return startIndex; vx\r!]
} ih)zG
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publicvoid setStartIndex(int startIndex){ Gw=B:kGk
if(totalCount <= 0) ?yZ+D z\
this.startIndex = 0; N%kt3vmQ_
elseif(startIndex >= totalCount) zofa-7'Bn
this.startIndex = indexes toLV4BtIG
hZdoc<
[indexes.length - 1]; `CBZhI%%
elseif(startIndex < 0) "/yC@VC>
this.startIndex = 0; 16w|O|^<
else{ ,k.3|aZE
this.startIndex = indexes Gq+z /Be
f W!a|?e$
[startIndex / pageSize]; 9FoHD
} vGvf<ra;H
} s kvGU(G}
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publicint getNextIndex(){ *lYVY)L
int nextIndex = getStartIndex() + 5c9^-|-T
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pageSize;
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if(nextIndex >= totalCount) ~Uj=^leYO
return getStartIndex(); ;m0~L=w
else :Hn6b$Vy8
return nextIndex; :uP,f<=)K
} kh!FR u h
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publicint getPreviousIndex(){ VdPtPq1
int previousIndex = getStartIndex() - ?OId\'q
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pageSize; rr+|Zt
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if(previousIndex < 0) V n7*JS
return0; NYt&@Z}]
else s0\X ^
return previousIndex; ? 8)'oMD
} `V=N*hv`
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} grS:j+_M2m
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抽象业务类 ^({})T0wu
java代码: %u? >#
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/** I*%-cA%l
* Created on 2005-7-12 G(Lzf(
*/ o#;b
package com.javaeye.common.business; t,QyfN
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import java.io.Serializable; $g@=Z"
import java.util.List; xRJ\E }/7
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import org.hibernate.Criteria;
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import org.hibernate.HibernateException; *Tas`WA
import org.hibernate.Session; ={_C&57N1
import org.hibernate.criterion.DetachedCriteria; !\"EFVH
import org.hibernate.criterion.Projections; qUh2hz:
import -jW.TT h]
7[w,:9& }
org.springframework.orm.hibernate3.HibernateCallback; 2n3W=dF
import 0f~C#/[t7
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org.springframework.orm.hibernate3.support.HibernateDaoS <_h~w}
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upport; MV<^!W
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import com.javaeye.common.util.PaginationSupport; "*($cQ$v
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public abstract class AbstractManager extends wy yWyf
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HibernateDaoSupport { ,eOB(?Ku
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privateboolean cacheQueries = false; ~{d$!`|a
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privateString queryCacheRegion; Z('Z
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publicvoid setCacheQueries(boolean rw: c
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cacheQueries){ FR$:"
this.cacheQueries = cacheQueries; W6f/T3
} AZ0;3<FfLp
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publicvoid setQueryCacheRegion(String L\Aq6q@c
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queryCacheRegion){ N8k00*p65
this.queryCacheRegion = Hcl(3>Jn2
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queryCacheRegion;
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} {F3xJ[
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publicvoid save(finalObject entity){ oT^{b\XN
getHibernateTemplate().save(entity); LISM ngQ.
} ./,/y"x
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publicvoid persist(finalObject entity){ qo p^;~
getHibernateTemplate().save(entity); B$-R-S6
} &7<TAo;O
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publicvoid update(finalObject entity){ yXz*5W_0D
getHibernateTemplate().update(entity); $@"l#vJPfc
} Y-pzy']4
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publicvoid delete(finalObject entity){ *#E
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getHibernateTemplate().delete(entity); Rd2qe /
} ZZk=E4aae
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publicObject load(finalClass entity, aAJU`=uq
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finalSerializable id){ IzsphBI
return getHibernateTemplate().load }x@2]juJ
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(entity, id); 18~>ZR
} (}a8"]Z
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publicObject get(finalClass entity, q-.,nMUF
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finalSerializable id){ wLmhy,
return getHibernateTemplate().get " 7!;KHc
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(entity, id); V@Rrn <l
} E^QlJ8
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publicList findAll(finalClass entity){ aEM %R<e
return getHibernateTemplate().find("from s}j{#xT
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" + entity.getName()); >_e]C}QUr
} K&nE_.kbl
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}@
publicList findByNamedQuery(finalString n1JRDw"e$$
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namedQuery){ sp#p8@Cj
return getHibernateTemplate e}Cif2#d~
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().findByNamedQuery(namedQuery); 9S-Z&2L
} PUF/#ck
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publicList findByNamedQuery(finalString query, L$9.8W
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finalObject parameter){ \n{qsf:
return getHibernateTemplate {. 2k6_1[
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().findByNamedQuery(query, parameter); @W vatD
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} >=RmGS
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publicList findByNamedQuery(finalString query, p<zSJLN
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finalObject[] parameters){ :z4)5=
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return getHibernateTemplate q<\,
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().findByNamedQuery(query, parameters); S'A>2>
} (5R?#vj
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publicList find(finalString query){ g6Q !8
return getHibernateTemplate().find
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(query); X}tVmO?
} My<snmr2d
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publicList find(finalString query, finalObject dQ_!)f&w1
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parameter){ h(M#f7'~&
return getHibernateTemplate().find cc#gEm)3C
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(query, parameter); R($KSui
} jqv- D
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public PaginationSupport findPageByCriteria b
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(final DetachedCriteria detachedCriteria){ 7bk%mQk
return findPageByCriteria u:[vaBh91
V\u>"3BQw
(detachedCriteria, PaginationSupport.PAGESIZE, 0); MO&}r7qq
} h v8P4"i v
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public PaginationSupport findPageByCriteria c/zJv*}x?
}RmU%IYc
(final DetachedCriteria detachedCriteria, finalint pcYG~pZ9
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startIndex){ Pm
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return findPageByCriteria p8Q,@ql.
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(detachedCriteria, PaginationSupport.PAGESIZE, )^4\,u\@
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startIndex); 3T"j)R_=l
} > `n,S
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public PaginationSupport findPageByCriteria &m|wH4\
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(final DetachedCriteria detachedCriteria, finalint T-5nB>)
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pageSize, hg+X(0
finalint startIndex){ :@ %4
return(PaginationSupport) *tgnYa[l
|
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getHibernateTemplate().execute(new HibernateCallback(){ W6"v)Jc>_
publicObject doInHibernate 3
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(Session session)throws HibernateException { eU<]o<
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Criteria criteria = O+?<h{"
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u
detachedCriteria.getExecutableCriteria(session); r41\r,`Dj
int totalCount = pcT:]d[1)
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((Integer) criteria.setProjection(Projections.rowCount ,!dh2xNH^
j:E<p_T
()).uniqueResult()).intValue();
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criteria.setProjection qW!]co
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(null); 1_\;- !t
List items = !1q 9+e
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criteria.setFirstResult(startIndex).setMaxResults q)Fq
i
?pn}s]*/
(pageSize).list(); SzUpWy&
PaginationSupport ps = oo=Qt(#
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new PaginationSupport(items, totalCount, pageSize, /%&2HDA)
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startIndex); $)RNKMZC}A
return ps; yto,>Utzg
} B>GE9y5
}, true); =0G!f$7^i
} qe!fk?T}
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public List findAllByCriteria(final =!`j7#:
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DetachedCriteria detachedCriteria){ |1b_3?e
return(List) getHibernateTemplate &|!7Z4N
T}"6wywM
().execute(new HibernateCallback(){ 'ow.=1N-
publicObject doInHibernate ?r?jl;A&
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(Session session)throws HibernateException { _cc#Qlw 7
Criteria criteria = sVJ!FC
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detachedCriteria.getExecutableCriteria(session); emdoA:w+
return criteria.list(); IRn2|
} m< 3Ao^I+
}, true); d1U\ft:gV
} yQ^($#Yk
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public int getCountByCriteria(final ~ug=
{b
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DetachedCriteria detachedCriteria){ 6S+U&Ce\
Integer count = (Integer) ]p;FZ4-T
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getHibernateTemplate().execute(new HibernateCallback(){ 7oq[38zB
publicObject doInHibernate '1$!jmY
q*2N{
(Session session)throws HibernateException { RTv
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Criteria criteria = lWqrU1Sjl
# g_Bx
detachedCriteria.getExecutableCriteria(session); RB+N
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return hWKJ,r%9;
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criteria.setProjection(Projections.rowCount >2< 8kBF_
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()).uniqueResult(); w^LuIbA
} 5!EJxP9
}, true); v@wb"jdFi$
return count.intValue(); [+OnV&
} D<V~f B
} v{9t]s>B
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用户在web层构造查询条件detachedCriteria,和可选的 Tp0bS
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 Y_]De3:V0B
1!.(4gV
PaginationSupport的实例ps。 hs?sGr
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ps.getItems()得到已分页好的结果集 JqMDqPIQ
ps.getIndexes()得到分页索引的数组 %zSuK8kxV
ps.getTotalCount()得到总结果数 fwBRWr9
ps.getStartIndex()当前分页索引 OX"j#
ps.getNextIndex()下一页索引 ;\[(- )f!=
ps.getPreviousIndex()上一页索引 5ux`U{`m
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 P(;?kg}0
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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 l983vKr
%/>Y/!;
一下代码重构了。 9JWa$iBH@
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我把原本我的做法也提供出来供大家讨论吧: JXw^/Y$
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首先,为了实现分页查询,我封装了一个Page类: #Jna6
java代码: HmZ{L +"
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/*Created on 2005-4-14*/ :Dd$i_3=
package org.flyware.util.page; +n7?S~R$
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/** TuW/N
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* @author Joa 1Jj Y!
* CEC
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*/ YFTjPBV
publicclass Page { ;r6jx"i
tw(JZDc
/** imply if the page has previous page */ [2dn\z28
privateboolean hasPrePage; /"?HZ% W
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/** imply if the page has next page */ ~`D|IWMDq
privateboolean hasNextPage; Z(ZiFPx2Z
?]rPRV
/** the number of every page */ VOr 1
privateint everyPage; PC qZNBN
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/** the total page number */ @rHK(25+d
privateint totalPage; YhRWz=l
;3
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/** the number of current page */ >+mD$:L
privateint currentPage; )NO<s0?&
MgC:b-&5_
/** the begin index of the records by the current T<I=%P)
m] W5+
query */ cS. -7
privateint beginIndex; (4@lKKiU%H
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/** The default constructor */ Uh'#izm[l
public Page(){ Lgz$]Jbl8
2jbIW*
} $46{<4.
-!)xQvagD.
/** construct the page by everyPage x)UwV
* @param everyPage !J=sk4T
* */ :d8W+|1u
public Page(int everyPage){ cv(PP-'\
this.everyPage = everyPage; Q.Aw2
} <jS~ WI@
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/** The whole constructor */ unJ R=~E
public Page(boolean hasPrePage, boolean hasNextPage, nkv(~ej(
@vMA=v7a
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int everyPage, int totalPage, O8]'o*<]
int currentPage, int beginIndex){ '<R>E:5
this.hasPrePage = hasPrePage; {} Bf
this.hasNextPage = hasNextPage; uHIiH@S
this.everyPage = everyPage; xcJ`1*1N
this.totalPage = totalPage; QW_agm
this.currentPage = currentPage; ]?h`:,]
this.beginIndex = beginIndex; [Px'\nVf
} }P3tn
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/** zd]D(qeX
* @return ,+;:3gRk9
* Returns the beginIndex. @R m-CWa
*/ D{v8q)5r
publicint getBeginIndex(){ `p'Q7m2y/b
return beginIndex; 7n o5b]
\
} XM<KF&pVB
x"4} isp<
/** ez3Z3t`
* @param beginIndex fZKt%m
* The beginIndex to set. kGkA:g:
*/ Y:ldR
publicvoid setBeginIndex(int beginIndex){ `imWc"'Ej
this.beginIndex = beginIndex; 0GDvwy D1
} :y2p@#l#
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/** D^U:
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* @return O g%U
* Returns the currentPage. fnCItK~y
*/ j%V["?)
publicint getCurrentPage(){ )c/Fasfg[P
return currentPage; 8wH.et25k
} NDO\B,7
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/** -S%x
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* @param currentPage +fKtG]$
* The currentPage to set. )R_E|@"
*/ K~RoUE<3[
publicvoid setCurrentPage(int currentPage){ xw<OLWW
this.currentPage = currentPage; W/=|/-\]/
} f-2$
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/** _)$PKOzbb
* @return A\Txb_x
* Returns the everyPage. @^ ik[9^H
*/ Ovw[b2ii
publicint getEveryPage(){ ~^)^q8
return everyPage; `A/j1UWJ
} wzjU,Mwe
/cFzotr"9
/** Fk=}iB#(
* @param everyPage Hqz?E@bc@
* The everyPage to set. Wk4.%tpeO7
*/ =\,
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publicvoid setEveryPage(int everyPage){ KyP)Qzp
this.everyPage = everyPage; K 3GSOD>
} ~9Cz6yF
uk`8X`'
/** m+$ @'TbP
* @return MVCl.o
* Returns the hasNextPage. V+wH?H=
*/ E{Pgf8
publicboolean getHasNextPage(){ !.5),2
return hasNextPage; MVv1.6c7Y
} {}>n{_
pN[0YmY#
/** IO.<q,pP!_
* @param hasNextPage o**y Z2
* The hasNextPage to set. ! o,5h|\
*/ ]r]k-GZ$
publicvoid setHasNextPage(boolean hasNextPage){ S\NL+V?7h
this.hasNextPage = hasNextPage; e yw'7
} VY 1vXM3y
qBk``!|s]
/** oCi
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* @return TB
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* Returns the hasPrePage. O';ew)tI
*/ )wzV
$(~
publicboolean getHasPrePage(){ 7q9gngT1LA
return hasPrePage; Q}2[hB
} dpN@#w
}b["Jk\2
/** x4a:PuqmGG
* @param hasPrePage 6\dX
* The hasPrePage to set. Md;/nJO~{
*/ VU!w!GN]Y
publicvoid setHasPrePage(boolean hasPrePage){ -[#n+`M
this.hasPrePage = hasPrePage; ~bA,GfSn0
} eo#^L}
#$'"cfRxc
/** j;P+_Hfe/E
* @return Returns the totalPage. s0LA^2U
* ^gro=Bp(
*/ h=RDO
publicint getTotalPage(){ >N`6;gn*l
return totalPage; _94s(~g:
} IvBGpT"(I
*8g<R
/** ]Nk!4"
* @param totalPage s'a= _cN
* The totalPage to set. v1[_}N9f>H
*/ 0^ !Gib
publicvoid setTotalPage(int totalPage){ hY\{|
this.totalPage = totalPage; p_terD:
} V/#v\*JHFc
sroGER.
} ]= x
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R e:T9K'e
1IA5.@G:
)q?$p9
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 /r$&]C:Fi
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个PageUtil,负责对Page对象进行构造: U1m\\<,
java代码: }#N]0I)JI
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/*Created on 2005-4-14*/ I^0t2[M
package org.flyware.util.page; <DiOWi
.5hp0L}
import org.apache.commons.logging.Log; 0-e
import org.apache.commons.logging.LogFactory; mc@M ,2@D
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/** {gkwOMW
* @author Joa 2)LX^?7R
* /(6zsq'v|
*/ }ymvC
publicclass PageUtil { #Q6w+"
=Lw3
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privatestaticfinal Log logger = LogFactory.getLog B\<ydN
a?<?5
(PageUtil.class); @!H
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/** af>3V( 7
* Use the origin page to create a new page C-#.RI7
* @param page ?eWJa
* @param totalRecords C6k4g75U2
* @return ?n*fy
*/ i!~>\r\6\
publicstatic Page createPage(Page page, int co]Gmg6p
Va9q`XbyO
totalRecords){ V<0$xV1b|=
return createPage(page.getEveryPage(), VO9f~>`(
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page.getCurrentPage(), totalRecords); x0x $ 9
} kEAhTh&g*
zA{8C];~
/** %h* 5xB]Tt
* the basic page utils not including exception 5~xeO@%I
%Dyh:h
handler Mvof%I
* @param everyPage NWISS
* @param currentPage [
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* @param totalRecords [h", D5
* @return page *)%dXVf
*/ i_Ar<9a~
publicstatic Page createPage(int everyPage, int =J.EH|
8t``NZ[
currentPage, int totalRecords){ %|?1B$s0
everyPage = getEveryPage(everyPage); !GN Xt4D
currentPage = getCurrentPage(currentPage); a!u3HS-i
int beginIndex = getBeginIndex(everyPage, R~c1)[[E
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currentPage); Ao*FcrXN
int totalPage = getTotalPage(everyPage, A}4t9|/K6
C"No5r'K3
totalRecords); +!$dO'0nt,
boolean hasNextPage = hasNextPage(currentPage, q!2<=:f
;Uk!jQh
totalPage); u%aFb*
boolean hasPrePage = hasPrePage(currentPage); M71R -B`-
(HSw%e
returnnew Page(hasPrePage, hasNextPage, RUc \u93n
everyPage, totalPage, *R!]47Y d
currentPage, $'u\B
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beginIndex); nt`<y0ta
} |8;?
*s`H
i@{*O@m
privatestaticint getEveryPage(int everyPage){ lVT&+r~r
return everyPage == 0 ? 10 : everyPage; [D9 :A
} "i''Ui\H
2lJZw@
privatestaticint getCurrentPage(int currentPage){ {kG;."S+K
return currentPage == 0 ? 1 : currentPage; GiqBzV3"
} %#4 +!
0%;MVMH
privatestaticint getBeginIndex(int everyPage, int W^|J/Y48
#XL`S
currentPage){ -#Jj-t_Fe
return(currentPage - 1) * everyPage; ]c,l5u}A$
} s<#N]mp'
4]u,x`6C
privatestaticint getTotalPage(int everyPage, int w=$'Lt!
JP_kQ
totalRecords){ q-uLA&4
int totalPage = 0; #-dK0<:
NCxn^$/+>9
if(totalRecords % everyPage == 0) kraVL%72
totalPage = totalRecords / everyPage; #}j]XWy
else Av[Ud
*~
totalPage = totalRecords / everyPage + 1 ; X=#It&m%s
wJ(8}eI
return totalPage; "_oLe;?$c
} .SBc5KX
jRwa0Px(
privatestaticboolean hasPrePage(int currentPage){ mOSCkp{<e
return currentPage == 1 ? false : true; mc~`
} s/PhXf\MN
fT
x4vlI4
privatestaticboolean hasNextPage(int currentPage, ]
EV`dIk
~RCg.&[ou
int totalPage){ u:eW0Ows"
return currentPage == totalPage || totalPage == [^Q&suy
.CvFE~
0 ? false : true; +|M{I= 8
} 8LeKwb
y*
rY~U#3
TL]bY'%
} `_0)kdu
@%%bRY
e+x*psQ
GGp{b>E+
#
0hb/`[Q
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 5C*?1&
!
ifd}]UMQ
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 /xF 9:r
6VGo>b;
做法如下: 0+p
5/5
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 CBIT`k.+
-@#Pc#
的信息,和一个结果集List: !&\meS{
java代码: Slo9#26
)L|C'dJ<k`
4^`PiRGt
/*Created on 2005-6-13*/ +{'lZa
package com.adt.bo; v/ eB,p
Jtext%"eNg
import java.util.List; RpU Lm1b
6G$/NW=L
import org.flyware.util.page.Page; t+jIHo
hO%Y{Gg
/** we
}#Ru*
* @author Joa
Hl!1h%
*/ G}s;JJax
publicclass Result { Q^vGj</u
#*+;B93)
private Page page; gfxoJihE
]u~Os<
private List content; \N6<BS
J/L)3y
/** +&(Jn
* The default constructor <Ak:8&$O
*/ 6(,ItMbI
public Result(){ N:twq&[Y
super(); oO8]lHS?@
} IC\E,m
V;P1nL4L
/** "Jf4N
* The constructor using fields .fbYB,0w
* l'W3=,G[?
* @param page k:`a+LiZ
* @param content 8u/3?Kc
*/ LPb]mC6#
public Result(Page page, List content){ j1W
bD7*8
this.page = page; 33O)k*g
this.content = content; @Ap@m6K?q
} +yt 6.L
7xz#D4[
/** |}:e+?{o
* @return Returns the content. bGhhh/n
*/ 3Gj(z:)b
publicList getContent(){ Pkj T&e)
return content; -6(h@F%E
} 5sG ]3z+1
]aREQ?ma&z
/** *X%?3"WH8
* @return Returns the page. sV]i/B
*/ @wg&6uQ
public Page getPage(){ Y"r3i]
return page; 58qaA\iw
} o-L|"3P
^ b=5 6~[
/** EPQ&?[6
* @param content M4R%Gr,La
* The content to set. M0Lon/%
*/ b (g_.1[
public void setContent(List content){ :8GlyN<E
this.content = content; 8[vl3C
} Pw0{.W~r
pZyb
/** GjG{qR
* @param page c& 9+/JYMo
* The page to set. [3 Wsc`Q
*/ K!pxDW}
publicvoid setPage(Page page){ ~vO'p
this.page = page; Sn;/;^@(\
} n%7A;l!{
} \Sz4Gr0g3Z
V22q*/iV
Uh<H*o6e 9
dw|-=~
DMy4"2
o
2. 编写业务逻辑接口,并实现它(UserManager, B7NmET4
Lr!L}y9T+
UserManagerImpl) s?4%<jz
java代码: oVKsic?
]9bh+
-U/I'RDLEz
/*Created on 2005-7-15*/ $}^Rsv(
package com.adt.service; m0dFA<5-
gt].rwo"
import net.sf.hibernate.HibernateException; }dV9%0s!
uJ2C+$=Ul
import org.flyware.util.page.Page; \c5#\1<
WM~J,`]J
import com.adt.bo.Result; }TXp<E"\
&!3VqHQ`
/** `kaR@t
* @author Joa a!s.850@
*/ ymzPJ??!
publicinterface UserManager { 3j[w
-Lfp
#n6FQ$l8m
public Result listUser(Page page)throws *y":@T
%[+a[/
HibernateException; 4GmSG,]
4]|9!=\
} ~ wJ3AqNC?
wj5qQ]WC
2zmQp
mR!&.R?
Q6s5#7h'"
java代码: Kt/+PS
iA1;k*)q
W(]E04
/*Created on 2005-7-15*/ LOyCx/n
package com.adt.service.impl; r1^m#!=B
5bGjO&$l
import java.util.List; J?|K#<%
yhJA;&}>
import net.sf.hibernate.HibernateException; *Bb|N--jI
dA_V:HP
import org.flyware.util.page.Page; \E ? iw.}
import org.flyware.util.page.PageUtil; C7XS6Nqu
!#_h2a
import com.adt.bo.Result; K%aPl~e
import com.adt.dao.UserDAO; #w%a
m`+
import com.adt.exception.ObjectNotFoundException; =+SVzK,+3
import com.adt.service.UserManager; YI? C-,
Nv*E .|G
/** S4aHce5PXA
* @author Joa a
V+o\fId
*/ 2f}K#i8
publicclass UserManagerImpl implements UserManager { D-2v>l_
]iE.fQ?;J
private UserDAO userDAO; jx5[bUp4u
lN][xnP
/** +*r**(-Dm
* @param userDAO The userDAO to set. JYVxdvq1
*/ {{4p{
publicvoid setUserDAO(UserDAO userDAO){ 1b
%T_a
this.userDAO = userDAO; {YO%JTQ
} p'uqh
e X
t^bdi}[
/* (non-Javadoc) S,)|~#5x
* @see com.adt.service.UserManager#listUser #sm_.?P
6|"!sW`%N
(org.flyware.util.page.Page) J4*:.8Ki
*/ w50Bq&/jX
public Result listUser(Page page)throws fW4cHB9|
[iO$ c]!H
HibernateException, ObjectNotFoundException { ,;+91lR3
int totalRecords = userDAO.getUserCount(); P(YG@
if(totalRecords == 0) NP<F==,
throw new ObjectNotFoundException HIWmh4o/.
zw%n!wc_\
("userNotExist"); +{=_|3(
page = PageUtil.createPage(page, totalRecords); \+evZ{Pu
List users = userDAO.getUserByPage(page); y}:)cA~o(y
returnnew Result(page, users); H2FFw-xW
} DESViQM
LGo@F;!n
} +~i+k~{`H
0:B^
mrLx]og,
057G;u/
8.;';[
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 P9tQS"Rs
/qz "I-a
询,接下来编写UserDAO的代码: mB|mt+
3. UserDAO 和 UserDAOImpl: M_e$l`"G
java代码: *|gs-<[#X
u6S0t?Udap
4htSwK+
/*Created on 2005-7-15*/ ==jw3_W
package com.adt.dao; &8_#hne_
R{OE{8;
import java.util.List;
;~gd<KK
cf[u%{
6Y
import org.flyware.util.page.Page; $ DZQdhv
1N$gE
import net.sf.hibernate.HibernateException; ]Re~V{uh
C +?@iMh
/** D8D!1 6_
* @author Joa +^&v5[$R
*/ T
m@1q!G
publicinterface UserDAO extends BaseDAO { 3}#XA+Z
b[[6X
publicList getUserByName(String name)throws |C)UZ4A/p
p,AD!~n`
HibernateException; EDidg"0p
}MavI'
publicint getUserCount()throws HibernateException; w[$nO#
b\0Q:
publicList getUserByPage(Page page)throws .dKRIFo
yL3<X w|
HibernateException; wq_oh*"
Y1E>T-Ma
} q[|`&6B
3Llj_lf
Zqs-I8y
a6k(O8Ank3
_9-D3_P[3
java代码: =u3@ Dhw
Z/05 wB
3Gd&=IJ
/*Created on 2005-7-15*/ ?'/5%f`
package com.adt.dao.impl; ox=7N{+`J
F)5B[.ce
import java.util.List; !|:q@|-
%@
t|U2ws#
import org.flyware.util.page.Page; QH' [(
n\"LN3
import net.sf.hibernate.HibernateException; 7" STS7_
import net.sf.hibernate.Query; $H:h(ia:
Qdr-GODx
import com.adt.dao.UserDAO; -z 5k4Y
.kKwdqO+zB
/** ~!d)J
* @author Joa ,S0~:c:)
*/ Mm7n?kb6
public class UserDAOImpl extends BaseDAOHibernateImpl eZod}~J8
ocuVDC
implements UserDAO { UrcN?
PUZXmnB
/* (non-Javadoc) F%+rOT<5
* @see com.adt.dao.UserDAO#getUserByName 6u, 0y$3
"QFADk1
(java.lang.String) AB&wn>q
*/ ;{q) |GRF
publicList getUserByName(String name)throws q>:&xR"ra
rD
U6 5j
HibernateException { 5<?c_l9X^
String querySentence = "FROM user in class AUjTcu>i
YG1`%,OW`
com.adt.po.User WHERE user.name=:name"; aLk2#1$g
Query query = getSession().createQuery qddT9U|8~
hUhp2ibEs
(querySentence); j% USu+&
query.setParameter("name", name); 8(/f!~
return query.list(); P ~
pbx
} 07"Oj9NlA
W]}V<S$
/* (non-Javadoc) ;ld~21#m
* @see com.adt.dao.UserDAO#getUserCount() 2[&-y[1
*/ zu*G4?]~h
publicint getUserCount()throws HibernateException { B{UoNm@
int count = 0; sAN:C{
String querySentence = "SELECT count(*) FROM v?TJ!o
3pv1L~ ZI
user in class com.adt.po.User"; hG;=ci3EE
Query query = getSession().createQuery y'O{8Q8T
8U:dgXz
(querySentence); EbYH?hPo
count = ((Integer)query.iterate().next O#5( U.E
cASHgm
()).intValue(); +M]8_kE=+l
return count; S=amj cC
} |j}F$*SE[
J$/BH\
/* (non-Javadoc) wBHDof
xX
* @see com.adt.dao.UserDAO#getUserByPage [gdPHXs
Ml/p{ *p
(org.flyware.util.page.Page) J+NK+,_*M
*/ Ry S{@=si
publicList getUserByPage(Page page)throws @d^h/w
gI5nWEM0{
HibernateException { Q!e0Vb
String querySentence = "FROM user in class 49fq6ZhO
<m:wuNEM
com.adt.po.User"; M*6@1.n
Query query = getSession().createQuery NP'DuzC
4"(zi5`e
(querySentence); O Lup`~
query.setFirstResult(page.getBeginIndex()) G( \1{"!
.setMaxResults(page.getEveryPage()); }~'Wz*Gm
return query.list(); "}+/0$F
} ;L%~c4`l~m
vGHYB1=~
} T>%ny\?tHW
JsEEAM:w
\\Tp40m+
*`.{K12T
5g>kr<K
至此,一个完整的分页程序完成。前台的只需要调用 >b?)WNk
z ;Nk& <?
userManager.listUser(page)即可得到一个Page对象和结果集对象 '0$[Ujc
}F`2$Q+CW
的综合体,而传入的参数page对象则可以由前台传入,如果用 W*`6ero
pDq_nx9
webwork,甚至可以直接在配置文件中指定。 TPFmSDq
f:&OOD o
下面给出一个webwork调用示例: "]V|bz o0a
java代码: * .VZ(wX
1+}Ud.v3VW
\o)4m[oF
/*Created on 2005-6-17*/ mM{v>Em2K#
package com.adt.action.user; ~Fb?h%w
swL|Ff`$
import java.util.List; k\%v;3nBK
<u wCP4E
import org.apache.commons.logging.Log; O9)}:++T
import org.apache.commons.logging.LogFactory; FNEmGz/4
import org.flyware.util.page.Page; %{abRBny
'k Z1&_{
import com.adt.bo.Result; ah9',( (!
import com.adt.service.UserService; 9G/2^PI
import com.opensymphony.xwork.Action; DJ0T5VE W3
\%Q
rN+WQ
/** lB~'7r`
* @author Joa $i>VI
*/ M?zAkHNS$
publicclass ListUser implementsAction{ P$Ru NF
a\_,_psK
privatestaticfinal Log logger = LogFactory.getLog Vdk+1AX
3F!+c 8e
(ListUser.class); ]sAD5<;
bI(98V,t
private UserService userService; }l!_m.#e
0N ;d)3
private Page page; i]?xM2(N
17MjIX
privateList users; Qo *]l_UO;
ACltV"dB^
/* }*R6p?L5
* (non-Javadoc) 7"i*J6y*
* a`Zf_;$@
* @see com.opensymphony.xwork.Action#execute() toJ&$HrE
*/ Pv.@Y30
publicString execute()throwsException{ v ed
Qwzh
Result result = userService.listUser(page); 0M+tKFb
page = result.getPage(); ~"Ki2'j)^]
users = result.getContent(); uwA3!5
return SUCCESS; TN`:T.B
} yo?Q%w'Nh
s9Z2EjQV
/** :q1r2&ne
* @return Returns the page. $7d"9s\$"
*/ $u"$mg7x
public Page getPage(){ ??V["o T
return page; qDb}b d5
} c%.&F
.p>8oOp
/** &[5az/Hj*
* @return Returns the users. L{p-'V
*/ ht9b=1wd%s
publicList getUsers(){ H]X)@n>
return users; EPy/6-5b
} hGV/P94
Q#KjX;No
/** 4/>={4Y9
* @param page lej{VcG
* The page to set. 0{F.DDiNT
*/ glgk>83I+
publicvoid setPage(Page page){ sc60:IxgI
this.page = page; #mYxO
} =YIQ
_,{u
Hp!F?J7sx
/** P7-3Vf_L
* @param users IhLfuyFWu
* The users to set. 0aWb s$FyU
*/ Q,`kfxA`O
publicvoid setUsers(List users){ 2_X0Og8s[
this.users = users; sf0U(XYQ^
} W$S.?[X
|3m%d2V*hF
/** uLF55:`<
* @param userService oVW?d]R
* The userService to set. h[T3WE
*/ e
AjtW qg
publicvoid setUserService(UserService userService){ T`sM4 VWqU
this.userService = userService; 9MxGyGz$
} hgGcUpJy?
} mGvP9E"&
4>* `26
Vk-_H)*r
JB<4m4-
@4$E.q<0
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, +$5^+C\6A
K<GCP2
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 HrGX-6`
=P{RHhWy;
么只需要: 's<}@-]
java代码: e{&gF1"[
3yN1cd"#?
BL67sva;
<?xml version="1.0"?>
sa* -B
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork Gj 3/&'k6
'Iu(lpF&
1.0//EN" "http://www.opensymphony.com/xwork/xwork- *OiHrI9y
0i"OG( ,
1.0.dtd"> Xl;N=fc
UB}mI0/w
<xwork> u:ISwAp
,dBI=D'
<package name="user" extends="webwork- m='OnTeOE
l<0V0R(
interceptors"> > R=YF*t
7[LC*nrr
<!-- The default interceptor stack name :Kiu*&{
&kvVMnok
--> qb&*,zN
<default-interceptor-ref t
At+5H
r DuG["
name="myDefaultWebStack"/> k"J?-1L
zVu}7v()
<action name="listUser" OK=t)6&b
GF&"nW9A
class="com.adt.action.user.ListUser"> 5 *_#"
<param /l
L*U
|UG)*t/
name="page.everyPage">10</param> T[~X~dqwn"
<result Lst5
(C&f~U
name="success">/user/user_list.jsp</result> R<-KXT9
</action> &3<]FK
&!ZpBR(
</package> b11C3TyQT
*RPI$0
</xwork> \XC1/LZQ
c{~*\&
*"@P2F&
I,D=ixK
'PZJ{8=
Gx
m"HC
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 <d4^gAfs*
k.%F!sK
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。 vJ!t.Vou
R-ci?7d t3
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 /-T%yuU
lI9 3{!+>
5s;#C/ZZ
c!zu0\[Id
W8)GT`\
我写的一个用于分页的类,用了泛型了,hoho f&:g{K
qpZ".
java代码: VuGSP]$q
YpJzRm{Ra
Hogr#Sn2
package com.intokr.util; |c)#zSv
ec|IT0;
import java.util.List; {PZe!EQ
3iB8QO;pp
/** Nbr{)h
* 用于分页的类<br> `g7'
)MSy
* 可以用于传递查询的结果也可以用于传送查询的参数<br> q07>FW R
* ;RXv%ML
* @version 0.01 ]Sh&8 #
* @author cheng ][3 "xP
*/ ctf'/IZ5
public class Paginator<E> { !|D,cs
privateint count = 0; // 总记录数
u!(|y9p
privateint p = 1; // 页编号 |$Td-M^)
privateint num = 20; // 每页的记录数 CXa$QSu >
privateList<E> results = null; // 结果 ~/t#J
6 `'^$wKs
/** 61wiXX"N
* 结果总数 }+z}vb
*/ fYwumx`J
publicint getCount(){ pcE.
return count; gbvBgOp
} t^q/'9Ai&J
`| fF)kI
publicvoid setCount(int count){
FkH4|}1
this.count = count; K.z@Vx.
} %lujme
@^%# ]x,:
/** _b+3;Dy
* 本结果所在的页码,从1开始 t<4+CC2H
* K~uoZ~_gA
* @return Returns the pageNo. *Nv<,Br,F
*/ Rcu/ @j{O
publicint getP(){ {|qz>
return p; cB|](gWS~
} t ,0~5>5
g%K3ah
v
/** JWLQ9UX
* if(p<=0) p=1 lm$T`:c
* wDn5|F}i&
* @param p "F=O
*/ _]B'C
publicvoid setP(int p){ 5'X.Z:
if(p <= 0) rKO[;]_*
p = 1; ^+-i7`|=
this.p = p; Yt&^i(
} DwoO([&I
%#=
1?1s
/** #fQStO
* 每页记录数量 8kk$:8
*/ J:t1W=lJ3
publicint getNum(){ 1|2X0Xm{
return num; LcQ \d*
} lE4.O
zH.7!jeE
/** 0 j6/H?OT
* if(num<1) num=1 ^X^4R1V)
*/ X[R/j*K
publicvoid setNum(int num){ DEs/?JZG
if(num < 1) ,2"-G";!f\
num = 1; \ZXH(N*>2t
this.num = num; ]2?t$"G8
} Z O&5C6qa
=YR/|9(
/** 9\V^q9l
* 获得总页数 1%H]2@
*/ 8!1vsEqv
publicint getPageNum(){ G"wy?
return(count - 1) / num + 1; 0Y{A
} W@#Y/L:${
%;GDg3L[p
/** _Y=>^K]9K
* 获得本页的开始编号,为 (p-1)*num+1 ?,]25q
*/ QDs]{F#
publicint getStart(){ ^ [2A<
g
return(p - 1) * num + 1; k5(@n>p
} oGa8}Vtc
l9\
*G;
/** t
7+ifSrz
* @return Returns the results. LG(bdj"NM
*/ <yBZsSj
publicList<E> getResults(){ PC/Oo~Gx
return results; q'[5h>Pa
} 4&}LYSZl
G;MmD?VJ g
public void setResults(List<E> results){ H{yeN 5
this.results = results; u[})|x*N
} 2ACN5lyUS
L'.7V ~b{
public String toString(){ I6~.sTl
StringBuilder buff = new StringBuilder =
oQ-I
Y`w+?}(M
(); _uID3N%
buff.append("{"); Ng2qu!F7
buff.append("count:").append(count); kU0e;r1 N
buff.append(",p:").append(p); nKT\ /}d
buff.append(",nump:").append(num); l@%MS\{
buff.append(",results:").append
a?_N8|k[
6|L<?
X
(results); m!V ?xGKJ
buff.append("}"); h#a,<B|
return buff.toString(); 82{Lx7pI
} gh#9<
QOB>TvE
} 1Jjay#
,E<(K8
unKi)v1