Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 xErb11
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 8;#yXlf
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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 +[_3h9BK
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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 W!Fc60>p@f
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分页支持类: "\=Phqw
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java代码: vu#ZLq
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package com.javaeye.common.util; 4u"Bll
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import java.util.List; Rd|8=`)
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publicclass PaginationSupport { sx}S,aIU
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publicfinalstaticint PAGESIZE = 30; JbQY{z!
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privateint pageSize = PAGESIZE; 5;,h8vW
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privateList items; b4WH37,lA
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privateint totalCount; ]vP}K
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privateint[] indexes = newint[0]; N_Kdi%q
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privateint startIndex = 0; I~&9c/&
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public PaginationSupport(List items, int i];P!Gm
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totalCount){ #<ST.f@*
setPageSize(PAGESIZE); y@<2`h
setTotalCount(totalCount); -a &<Un/
setItems(items); bLAHVi<.
setStartIndex(0); 32j}ep.*
} R&a$w8
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public PaginationSupport(List items, int OZnKJ<
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totalCount, int startIndex){ h /^bRs`;
setPageSize(PAGESIZE); D79:L:
setTotalCount(totalCount); RtzSe$O
setItems(items); f'H|K+bO
setStartIndex(startIndex); !!H"B('m
} /XEW]/4
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public PaginationSupport(List items, int "=T&SY
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totalCount, int pageSize, int startIndex){ c38XM]Jeq
setPageSize(pageSize); oPM*VTMA
setTotalCount(totalCount); J}:.I>
setItems(items); v{fcQb
setStartIndex(startIndex); +38R#2JV
} y!.jpF'uI
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publicList getItems(){ Y`Io}h G$
return items; Vm>E F~ r
} 7-!n-
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publicvoid setItems(List items){ VL$
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this.items = items; >[,eK=
} ,1$F#Eh
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publicint getPageSize(){ gJ'pwSA
return pageSize; $t(v `,
} PD-&(ka.
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publicvoid setPageSize(int pageSize){ q`b6if"
this.pageSize = pageSize; )J}v.8
} UI+6\ 3
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publicint getTotalCount(){ ~<m^
return totalCount; 8Auek#[
} C;N6",s!
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publicvoid setTotalCount(int totalCount){ 7RL J
if(totalCount > 0){ VNHceH
this.totalCount = totalCount; hx$61E=
int count = totalCount / 1x:W 3.
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pageSize; 2Lf,~EV
if(totalCount % pageSize > 0) Qs6Vu)U=
count++; ir_XU/ve
indexes = newint[count]; d8wVhZKI"
for(int i = 0; i < count; i++){ ` 3qf}=Z`
indexes = pageSize * 30!DraW8
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} "w'pIUQ3,
}else{ >u&D@7~c
this.totalCount = 0; s)a-ky(
} oAQQ OtpZN
} `
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publicint[] getIndexes(){ olE(#}7V
return indexes; YsVmU
} L0fe
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publicvoid setIndexes(int[] indexes){ [a2]_]E%
this.indexes = indexes; FvpU]
} cag 5w~Px
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publicint getStartIndex(){ $[>{s9E
return startIndex; _ ;j1g%
} MA`nFkVK
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publicvoid setStartIndex(int startIndex){ j=l2\W#}
if(totalCount <= 0) bY" zK',m
this.startIndex = 0; i%K6<1R;y{
elseif(startIndex >= totalCount) 2/&=:,"t,B
this.startIndex = indexes An.
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[indexes.length - 1]; 9zwD%3Ufn
elseif(startIndex < 0) o$*(N
this.startIndex = 0; n/_q
else{ P0l
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this.startIndex = indexes W{F)YyR{.
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[startIndex / pageSize]; F1#{(uW
} 7;EDU
} >3!~U.AA'x
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publicint getNextIndex(){ 6!\V|
int nextIndex = getStartIndex() + >v+1v
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pageSize; zZCl]cql
if(nextIndex >= totalCount) x%viCkq
return getStartIndex(); jY=y<R_oK
else m!FuC=e
return nextIndex; <?.eU<+O`S
} b Hr^_ogN
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publicint getPreviousIndex(){ #X-C~*|>j
int previousIndex = getStartIndex() - {=GmXd%D
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pageSize; R-Edht|{
if(previousIndex < 0) \s)MNs
return0; \S;[7T
else #[prG
return previousIndex; T!c|O3m
} Y#F.{i
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} 05wkUo:9
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抽象业务类 JvAXLT
java代码: `%Ih'(ne
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/** c(Dp`f,
* Created on 2005-7-12 ~5P9^`KNH
*/ eo]nkyYDP
package com.javaeye.common.business; qyRN0ZB"A^
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import java.io.Serializable; Y<T0yl?
import java.util.List; IW\^-LI.
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import org.hibernate.Criteria; 0F)v9EK(W4
import org.hibernate.HibernateException; h.Qk{v
import org.hibernate.Session; $ar^U
import org.hibernate.criterion.DetachedCriteria; B:"D)/\
import org.hibernate.criterion.Projections; !<];N0nt#
import V(`]hH0;T
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org.springframework.orm.hibernate3.HibernateCallback; IHEbT
import XM\\Imw
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org.springframework.orm.hibernate3.support.HibernateDaoS }TTghE!
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upport; T~3{$
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import com.javaeye.common.util.PaginationSupport; Au2?f~#Fv
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public abstract class AbstractManager extends UBL{3s^"
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HibernateDaoSupport { ,b5'<3\
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privateboolean cacheQueries = false; qm=U<'b^
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privateString queryCacheRegion; Z
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publicvoid setCacheQueries(boolean 7^i7U-A<A
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cacheQueries){ [63\2{_^v
this.cacheQueries = cacheQueries; n3p@duC4
} s)WA9PiC
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publicvoid setQueryCacheRegion(String ?>;b,^4
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queryCacheRegion){ (xo`*Q,+
this.queryCacheRegion = i
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queryCacheRegion; =DdPwr 0Op
} P^OmJ;""D
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publicvoid save(finalObject entity){ :6Z2@9.}w
getHibernateTemplate().save(entity); NFTv4$5d
} 6:(s8e
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publicvoid persist(finalObject entity){ }.o.*N
getHibernateTemplate().save(entity); rN9qH
} g-K;J4 K%
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publicvoid update(finalObject entity){ T^4 dHG-(
getHibernateTemplate().update(entity); ;U3:1hn
} s?HK2b^;D
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publicvoid delete(finalObject entity){ [yMSCCswW
getHibernateTemplate().delete(entity); -+[Lc_oNPx
} MiZ<v/L2
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publicObject load(finalClass entity, H5 z1_O_+
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finalSerializable id){ +rv##Z
return getHibernateTemplate().load rf=l1GW
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(entity, id); QqQhQ GV
} |fKT@2(
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publicObject get(finalClass entity, 9}QIqH\p
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finalSerializable id){ oaQW~R`_
return getHibernateTemplate().get F'|K>!H
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(entity, id); ?lkB{-%rQ
} el2Wk@*
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publicList findAll(finalClass entity){ w<H2#d>5!@
return getHibernateTemplate().find("from 8XYxyOl
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" + entity.getName()); ;"cQ)=s9Y
} )Wle
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publicList findByNamedQuery(finalString D SX%SE)
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namedQuery){ Z-lhJ<0/Pa
return getHibernateTemplate Gx$m"Jeq\
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().findByNamedQuery(namedQuery); :
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} :xHKbWz6j
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publicList findByNamedQuery(finalString query, AS]8rH
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finalObject parameter){ 9n is8
return getHibernateTemplate _`p-^I
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().findByNamedQuery(query, parameter); Sed8Q-m
} P>rRD`Yy\
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publicList findByNamedQuery(finalString query, l$1?@l$j
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finalObject[] parameters){ TgjjwcO Y
return getHibernateTemplate Ms +ekY)
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().findByNamedQuery(query, parameters); h! uyTgq
} #w%-IhP
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publicList find(finalString query){ L4B/
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return getHibernateTemplate().find 05{}@tW-
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(query); k62s|VeU
} aV7VbC
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publicList find(finalString query, finalObject OqS!y(
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parameter){ f.$[?Fi
return getHibernateTemplate().find h2x9LPLBxT
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(query, parameter); C_>XtcU
} J*b Je"8
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public PaginationSupport findPageByCriteria q
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(final DetachedCriteria detachedCriteria){ x#3*C|A
return findPageByCriteria vu@.;-2E%
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); .xwskzJ3
} 0ZwXuq
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public PaginationSupport findPageByCriteria
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(final DetachedCriteria detachedCriteria, finalint 8#JX#<HEo
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startIndex){ >i*,6Psl[Z
return findPageByCriteria e`b#,=
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(detachedCriteria, PaginationSupport.PAGESIZE, b
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startIndex); 5b/ ~]v
} nS3Aadm
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public PaginationSupport findPageByCriteria ^wWbW&<Tg
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(final DetachedCriteria detachedCriteria, finalint ?-:2f#bC
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pageSize, fWq*Op.]c
finalint startIndex){ [5~mP`He
return(PaginationSupport) h_#=f(.'j
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getHibernateTemplate().execute(new HibernateCallback(){ ^D+^~>f
publicObject doInHibernate PlH~um[J
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(Session session)throws HibernateException { BZ:tVfg.
Criteria criteria = xrvM}Il
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detachedCriteria.getExecutableCriteria(session); DNq(\@x[!
int totalCount = Jf?6y~X>Y
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((Integer) criteria.setProjection(Projections.rowCount Bz_'>6w
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()).uniqueResult()).intValue(); f/O6~I&g
criteria.setProjection mTI`^e
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(null); 8lpAe0p(Z
List items = .+ u
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criteria.setFirstResult(startIndex).setMaxResults GKo&?Tj)
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(pageSize).list(); z4SJxL
PaginationSupport ps = Oq.ss!/z
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new PaginationSupport(items, totalCount, pageSize, t([}a~1}
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startIndex); dW4jkjap
return ps; ;9k>;g3m
} }?9&xVh?\
}, true); o0 C&ol_
} viAAb
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public List findAllByCriteria(final 6`CRT TJ7
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DetachedCriteria detachedCriteria){ Ldjz-
return(List) getHibernateTemplate uem-fTG
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().execute(new HibernateCallback(){ -Ty~lZ)TDT
publicObject doInHibernate }aRib{L
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(Session session)throws HibernateException { f zo'9
Criteria criteria = e7U\gtZ.
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detachedCriteria.getExecutableCriteria(session); +\Vm t[v
return criteria.list(); #; ?3kuq(
} ~+dps i
}, true); }'x;J
} 06pvI}
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public int getCountByCriteria(final }9S}?R
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DetachedCriteria detachedCriteria){ lDYgtUKG
Integer count = (Integer) i
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getHibernateTemplate().execute(new HibernateCallback(){ C.jWT1
publicObject doInHibernate zi-_ l
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(Session session)throws HibernateException { nQc#AFg
Criteria criteria = }S/i3$F0~
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detachedCriteria.getExecutableCriteria(session); |ri)-Bk
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return @oA z
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criteria.setProjection(Projections.rowCount A"V
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()).uniqueResult(); eQbHf
} sasurR|;
}, true); P"w\hF
return count.intValue(); I'uwJy_I\
} 7PY$=L48A
} !ZBtXt#P
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用户在web层构造查询条件detachedCriteria,和可选的 =01X
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ukWn@q*
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PaginationSupport的实例ps。 |9I)YD
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ps.getItems()得到已分页好的结果集 L)sgW(@2
ps.getIndexes()得到分页索引的数组 HxG8'G
ps.getTotalCount()得到总结果数 <g[z jV9p
ps.getStartIndex()当前分页索引 ?5C'9 V
ps.getNextIndex()下一页索引 x;/LOa{LR
ps.getPreviousIndex()上一页索引 Aedf (L7\
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 $T'!??|IF
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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 jj5S+ >4
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一下代码重构了。 (`tRJWbdz
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我把原本我的做法也提供出来供大家讨论吧: 6%v9o?:~l
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首先,为了实现分页查询,我封装了一个Page类: Luq4q95]
java代码: (j:
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/*Created on 2005-4-14*/ (`P\nnb
package org.flyware.util.page; z|l*5@p
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/** '%Ng lC[J
* @author Joa E[H
* 9njwAKF?
*/ &.?XntI9O
publicclass Page { )#=J<OpG
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/** imply if the page has previous page */ Gz[yD
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privateboolean hasPrePage; )-C3z
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/** imply if the page has next page */ CD|[PkjW
privateboolean hasNextPage; C-'hXh;hQ
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/** the number of every page */ W yL+HB}
privateint everyPage; zw0w."V
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/** the total page number */ K1B9t{T
privateint totalPage; [Kgb#L'{
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/** the number of current page */ qWt}8_"
privateint currentPage; ()3\(d5e
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/** the begin index of the records by the current bOS)vt*V
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query */ sp9gz~Kq
privateint beginIndex; o4(*nz
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/** The default constructor */ 5j%G7.S\
public Page(){ |{ jT+
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} hsZ/Vnn`
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/** construct the page by everyPage \bA Yic
* @param everyPage 1J@Iekat
* */ R%E7 |NAG
public Page(int everyPage){ U,
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this.everyPage = everyPage; )G? qX.D
} DL]tg[w{
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/** The whole constructor */ @NHh-&;w
public Page(boolean hasPrePage, boolean hasNextPage, d|`Ll
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int everyPage, int totalPage, 5En6f`nR{
int currentPage, int beginIndex){ vDy&sgS$<
this.hasPrePage = hasPrePage; iyskADS
this.hasNextPage = hasNextPage; "L~(%Nx3
this.everyPage = everyPage; oFY!NMq}:
this.totalPage = totalPage; CSk]c9=
this.currentPage = currentPage; ,pNx(a
this.beginIndex = beginIndex; #;!&8iH
} ,Z.sGv
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/** L9x-90'q,
* @return `i7r]
* Returns the beginIndex. Bq0 \T
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*/ p!.~hw9
publicint getBeginIndex(){ gk ]QR.
return beginIndex; XtF
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} ?J[3_!"t
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/** ]B8
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* @param beginIndex {]vD@)k
* The beginIndex to set. '\Xkvi
*/ ?Ua,ba*
publicvoid setBeginIndex(int beginIndex){ "kg`TJf=
this.beginIndex = beginIndex; W,q @ww u
} Iv`IJQH>
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/** 5&Oc`5QD
* @return :yay:3qv
* Returns the currentPage. Cu"Cpt[
*/ x)5}:b1B=
publicint getCurrentPage(){ DA=!AK>
return currentPage;
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} qTO6I5u
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/** 7]{g^g.9-
* @param currentPage K g@'mG
* The currentPage to set. P<<$o-a"
*/ +9)JtmoL
publicvoid setCurrentPage(int currentPage){ z^Q'GBoBA
this.currentPage = currentPage; )0{`}7X
} De $AJl
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/** 9>}&dQ8
* @return lH-VqkR\
* Returns the everyPage. J8|MK.oD
*/ 'o$j~Mr
publicint getEveryPage(){ MJn-] E
return everyPage; 56.!L
} +ikSa8)*i
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/** p8Vqy-:
* @param everyPage MlO OB
* The everyPage to set. .ZXoRT
*/ 7*:zN
publicvoid setEveryPage(int everyPage){ FaHOutP
this.everyPage = everyPage; XqH@3Ehk
} /\J0)V
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/** -H|
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* @return L G}{ibB
* Returns the hasNextPage. wmVmGa
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*/ rYUIFPN
publicboolean getHasNextPage(){ ]HKt7 %,
return hasNextPage;
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} a`O'ZY
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/** \S}/2]* 1
* @param hasNextPage "ubp`7%67
* The hasNextPage to set. Y;'<u\^M"
*/ \C~X_/sg
publicvoid setHasNextPage(boolean hasNextPage){ IQqUFP$8g
this.hasNextPage = hasNextPage; 84ij4ZYe
} TrI+F+;
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/** MU<(O}
* @return x}G:n[B7_V
* Returns the hasPrePage. ?kjQ_K
*/ .7iRV
publicboolean getHasPrePage(){ $]7f1U_e
return hasPrePage; E@VQxB7+
} +eVYy_bL-
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/** 8SRR)O[)}
* @param hasPrePage eORXyh\K
* The hasPrePage to set. W"\~O"a
*/ g`fG84
publicvoid setHasPrePage(boolean hasPrePage){ K EAXDF
this.hasPrePage = hasPrePage; $6"sR I6u
} Vl.,e1)6
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/** 2D 4,#X
* @return Returns the totalPage. JCWTB`EB>
* ;m7V]h? R
*/ zt.kNb
publicint getTotalPage(){ 17hoX4T
return totalPage; Ai/X*y:[?
} 2 6#p,P
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/** b{0a/&&1O
* @param totalPage c^}G=Z1@
* The totalPage to set. O|Uz)Y94
*/ y2W+YV*
publicvoid setTotalPage(int totalPage){ 9qx4F<
this.totalPage = totalPage; `[H^`
} 4`O[U#?
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} Zue3Z{31T
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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 zgD?e?yPO
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个PageUtil,负责对Page对象进行构造: vQ rxx
java代码: l7`{ O/hN
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/*Created on 2005-4-14*/ #]h
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package org.flyware.util.page; 6Bq_<3P_
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import org.apache.commons.logging.Log; ~5
6&!4
import org.apache.commons.logging.LogFactory; rKgl:sj+
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/** ni;)6,i
* @author Joa @i ~ A7L0/
* y._'o7 %
*/ ~'M<S=W
publicclass PageUtil { j]Gn\QF
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privatestaticfinal Log logger = LogFactory.getLog {
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(PageUtil.class); 4/
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/** U7WYS8
* Use the origin page to create a new page /3s&??{tv
* @param page kN=&"
* @param totalRecords {aAd (~YZ
* @return h,c*:
*/ b8d0]YS
publicstatic Page createPage(Page page, int =p+n(C/
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totalRecords){ m%0-3c(
return createPage(page.getEveryPage(), :
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page.getCurrentPage(), totalRecords); Snk+ZQ-
} ?NwrdcQ
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/** L{1sYR%s\
* the basic page utils not including exception FKO2UY#&7
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handler ,X4b~)
* @param everyPage a``|sn9
* @param currentPage #@FA=p[%
* @param totalRecords i~h@}0WR"
* @return page cWAw-E5
*/ )$] lf }
publicstatic Page createPage(int everyPage, int ,l~<|\4,wv
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currentPage, int totalRecords){ k6C XuU
everyPage = getEveryPage(everyPage); 8>YF}\D V
currentPage = getCurrentPage(currentPage); W6<oy
int beginIndex = getBeginIndex(everyPage, ^fsMfB
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currentPage); F*P0=DD
int totalPage = getTotalPage(everyPage, +gd5&
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totalRecords); mG
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boolean hasNextPage = hasNextPage(currentPage, :)#;0o5
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totalPage); _:Qh1 &h
boolean hasPrePage = hasPrePage(currentPage); Q]9$dr=Kk0
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returnnew Page(hasPrePage, hasNextPage, X%b1KG|#(
everyPage, totalPage, s#Dj>Fej
currentPage, CY o
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beginIndex); 4<Vi`X7[F
} Z8E<^<|
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privatestaticint getEveryPage(int everyPage){ M5no4P<
return everyPage == 0 ? 10 : everyPage; rxyv+@~Nc
} {VAih-y
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privatestaticint getCurrentPage(int currentPage){ ]c>@RXY'
return currentPage == 0 ? 1 : currentPage; MtJ-pa~n
} |2do8z
zyS8LZ-y9
privatestaticint getBeginIndex(int everyPage, int l\Ozy
]nsjYsT
currentPage){ TipH}
return(currentPage - 1) * everyPage; 3%*igpj\)
} l>\EkUT
PIH\*2\/
privatestaticint getTotalPage(int everyPage, int ]r;rAOWVV
4vg3F(
totalRecords){ WX4sTxJK
int totalPage = 0; r(r(&NU
hi,="
/9
if(totalRecords % everyPage == 0) UPH#~D!
totalPage = totalRecords / everyPage; &m3-][!n
else eu5te0{G
totalPage = totalRecords / everyPage + 1 ; CtY-Gs
<)ZQRE@
return totalPage; Pk;w.)kT
} KZ2[.[(Ph
fAJyD`]Z
privatestaticboolean hasPrePage(int currentPage){ *}vvS^ c0
return currentPage == 1 ? false : true; [r`KoHwdm
} UIEvwQ
xVPSL#>
privatestaticboolean hasNextPage(int currentPage, 0$|VkMq(
!l*A3qA
int totalPage){ -f |/#1
return currentPage == totalPage || totalPage == d~8U1}dP
<PSz`)SN
0 ? false : true;
!`_f
} >n,_Aj
c
Qm[((6}
wKpGJ&
{
} =OK#5r[UV
F/2cQ.u2
04U|Frc
2xN7lfu1RB
SAnr|<Y/
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 <qR$ `mLN
IX+Jf? &^
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 :Pq&l.
u[qy1M0
做法如下: k1D7=&i
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 D:9^^uVp
4>(K~v5;N
的信息,和一个结果集List: mywxV
java代码: 9,fV
2- L-=0
#N`'hPD}
/*Created on 2005-6-13*/ ai?uJ}
package com.adt.bo; TU?n;h#TZ
^U~Er'mT
import java.util.List; Wqv7
HZ<#H3_ix
import org.flyware.util.page.Page; #xmiUN,|
_A]jiPq
/** *4~7p4[
* @author Joa wp:$Tq a$
*/ s-*N_Dv
publicclass Result { 8GxT!
tgBA(2/Co
private Page page; wSjy31
7eq.UyUxs
private List content; =3,<(F5Y[
hak#Iz0[C
/** >kAJS??
* The default constructor 5M\0t\uEn
*/ x75;-q
public Result(){ 5%S5*c6BD
super(); a?Om;-i2`S
} ]Q^8
9?
J>dj]1I
/** Jur$O,u40l
* The constructor using fields h1>.w
pr
* 3>(~5
* @param page a:|]F|
* @param content .aZB?MW
*/ _)-2h[
public Result(Page page, List content){ ,hK
=x
this.page = page; DvEII'-h
this.content = content; yMNOjs'c {
} Qvny$sr2
m";8 nm
/** =uwG.,lC
* @return Returns the content. >&<D.lx
*/ \mN?5QCcE
publicList getContent(){ \i~5H]?d
return content; avS9 "e
} P)TeF1~T
'H1"z!]
/** kH=~2rwm
* @return Returns the page. K6<1&
*/ *|+ ~V/#
public Page getPage(){ GmGq69]J*
return page; _}Gs9sHr0K
} :+DAzjwO<
cNN_KA
/** b=Sl`&A
* @param content *7Sg8\wDn
* The content to set. '\m\$
{
*/ qfY=!|O
public void setContent(List content){ 1 _W5@)
this.content = content; MD:kfPQ
} nfvs"B;
6a`_i
/** YpZ9h@,
* @param page #iGz&S3iN$
* The page to set. m4P=,=%
*/ :kI
x?cc
publicvoid setPage(Page page){ Z@i MG
this.page = page; 13{"sY:PT#
} c9E9Rx
} DPtyCgH
*DoEDw
]i]sgg[
S+OI?QS
L{CHAVkV
2. 编写业务逻辑接口,并实现它(UserManager, f{z%P I[
L@R%*-a
UserManagerImpl) CM's6qhQnn
java代码:
vrW9<{
KF-gcRh
*&2#;mf3
/*Created on 2005-7-15*/ 8QZk0O
package com.adt.service; Q}Vho.N@=
k~?}z.g(
import net.sf.hibernate.HibernateException; iii$)4V
+#H8d1^5
import org.flyware.util.page.Page; cwC,VYVl
~O
6~',KD
import com.adt.bo.Result; \M532_w
!V-SV`+X
/** n_ez6{
* @author Joa >a-+7{};
*/ K((Kd&E
publicinterface UserManager { ti#sh{t
$-AvH(@
public Result listUser(Page page)throws YV940A-n
Tk2kis(n
HibernateException; a&ByV!%%+_
B# H
} &lS0"`J=
7ER 2h*
v!U# C[a^
<d5vVn
835Upj>
java代码: v_@_J!s
R39R$\
xA5$!Oq7
/*Created on 2005-7-15*/ K]Cvk%
package com.adt.service.impl; ,"VQ0Z1
.M{[J]H`t
import java.util.List; E\*",MGL
Mqtp}<*@-
import net.sf.hibernate.HibernateException; Wkk Nyg,
eztk$o
import org.flyware.util.page.Page; ">QY'r
import org.flyware.util.page.PageUtil; >C}RZdO~
td&l T(7
import com.adt.bo.Result; |\(/dXXP
import com.adt.dao.UserDAO; ^Q,/C8qeb
import com.adt.exception.ObjectNotFoundException; *vO'Z &
import com.adt.service.UserManager; X[~CLKH(
Yc V~S#b
/** ncdr/(`
* @author Joa 8)!;[G|
*/ Fb'wC
publicclass UserManagerImpl implements UserManager { *n'xS L
kZ9pgdI
private UserDAO userDAO; \-0` %k"&
`x VA]GR4c
/** JrAc]=
* @param userDAO The userDAO to set. !v L:P2
*/ {@$3bQ
publicvoid setUserDAO(UserDAO userDAO){ UVJ(iNK"
this.userDAO = userDAO; -*M:OF"Zh
} Z :+#3.4$3
]c2| m}I{:
/* (non-Javadoc) 3T/j5m}+!
* @see com.adt.service.UserManager#listUser #+PbcL
ACYn87tq
(org.flyware.util.page.Page) TMCA?r%Y\
*/ |pR$' HO
public Result listUser(Page page)throws ?&m]du#6
Y7)@(7G)\
HibernateException, ObjectNotFoundException { #Vigu,zY
int totalRecords = userDAO.getUserCount(); }2,#[mM
if(totalRecords == 0) QZox3LM1&.
throw new ObjectNotFoundException gu[dw3L
UJ$:5*S=u
("userNotExist"); Ds_
"m,
page = PageUtil.createPage(page, totalRecords); 8Jj0-4]
List users = userDAO.getUserByPage(page); [Mc5N
returnnew Result(page, users); ~{G:,|`
} [B @j@&
a[g|APZz
} 6ya87H'e@
(v:ek_
oD@jtd>b%
wP0+Xv,
~9{;VKgK
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 A i){,nh`0
!o':\hex6
询,接下来编写UserDAO的代码: p3FnYz-V
3. UserDAO 和 UserDAOImpl: ko2j|*D6@~
java代码: 89#0vG7m
6n\z53Mk
)2Ru!l#
/*Created on 2005-7-15*/ fR%1FXpK&
package com.adt.dao; Wd56B+
M03i4R@h(
import java.util.List; D8AIVK]
S/<"RfVU#o
import org.flyware.util.page.Page; UW[{d/.wC
i6#]$ B
import net.sf.hibernate.HibernateException; JOx,19r
(2bZ]
/** @@3,+7%1
* @author Joa Vy^yV|`v
*/ O& %"F8B
publicinterface UserDAO extends BaseDAO { Tb1}XvZ
0O,T=z[+>
publicList getUserByName(String name)throws @U3foL2\
Vm;Qw
HibernateException; A9l})_~i
5Sjr6l3Vq8
publicint getUserCount()throws HibernateException; B5,QJ W*
\btR^;_\A
publicList getUserByPage(Page page)throws Hn9F
gul&
f./m7TZ
HibernateException; =PFR{=F
SAG`^t
} yvooM'R
2iPmCG
0YpiHoM
r3H}*Wpf
SQt|(r)
java代码: ,d>X/kd|o
33<fN:J]f
8S1P&+iKs
/*Created on 2005-7-15*/ S}w.#tyEn
package com.adt.dao.impl; }xf='lE
YF! &*6m
import java.util.List; cF_;hD|YZ
tSb?]J
import org.flyware.util.page.Page; <cDKGd
?H[5O+P[
import net.sf.hibernate.HibernateException; JXL9Gge
import net.sf.hibernate.Query; p`ADro*
%|*nmIPq(
import com.adt.dao.UserDAO; XatA8(_,5
ke}Y2sB
/** h
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* @author Joa uS,p|}Q&
*/ 5>ADw3z'
public class UserDAOImpl extends BaseDAOHibernateImpl B0)`wsb_
`y^zM/Ib
implements UserDAO { -7I1Lh#M
9U|<q
/* (non-Javadoc) vXyuEEe
* @see com.adt.dao.UserDAO#getUserByName 7`blGzP_
0~+NB-L}
(java.lang.String) NV}RRs
*/ |oe!P}u
publicList getUserByName(String name)throws b|sc'eP#?
g> ~cs_N@
HibernateException { l_c^ .D
String querySentence = "FROM user in class cW)Oi^q%o2
r"{Is?yKe
com.adt.po.User WHERE user.name=:name"; &GdL 9!hH
Query query = getSession().createQuery _m9~*
&l.x:eD
(querySentence); /x
query.setParameter("name", name); C9<4~IM
w
return query.list(); 0LWdJ($?
} 7fTxGm
AH&9Nye8
/* (non-Javadoc) xi680'
* @see com.adt.dao.UserDAO#getUserCount() wVgi+P
*/ 2c}B
publicint getUserCount()throws HibernateException { ow2M,KU6Z
int count = 0; {
EA2
String querySentence = "SELECT count(*) FROM <9ma(PFa
{]&R8?%
user in class com.adt.po.User"; \s=QiPK
Query query = getSession().createQuery R{*_1cyW
>9-Dd)<
(querySentence);
L~*u4
count = ((Integer)query.iterate().next W`#gpi)7N
`$J'UXtGc
()).intValue(); {bN Y
return count; 3PfiQ|/b
} fC_zX}3
saatU;V
/* (non-Javadoc) hzaU8kb
* @see com.adt.dao.UserDAO#getUserByPage z{%oJ_
KzV.+f
(org.flyware.util.page.Page) Ll,I-BQ9
*/ [ L
publicList getUserByPage(Page page)throws f,|QAj=a
mv{<'
HibernateException { ^>-+@+(
r
String querySentence = "FROM user in class .+OB!'dDK^
-:MmSeG7gO
com.adt.po.User"; Q\H_t)-
Query query = getSession().createQuery '?5S"??
$Jc q7E~
(querySentence); (}G!np
query.setFirstResult(page.getBeginIndex()) k!&:(]
.setMaxResults(page.getEveryPage()); mKM,kY
return query.list(); {t&*>ma6)
} YNI;h%w
:i.t)ES
} 1DUb
[W8
x.ba|:5
-OWZ6#v(
{#N%Bq}
R }1W
至此,一个完整的分页程序完成。前台的只需要调用 NddO*`8+)
*#zS^b n
userManager.listUser(page)即可得到一个Page对象和结果集对象 RB[/q:
i0\)%H:z
的综合体,而传入的参数page对象则可以由前台传入,如果用 SyAo,
)j
f~q4{
webwork,甚至可以直接在配置文件中指定。 Bhe{L?}0
:5jexz."M
下面给出一个webwork调用示例: z|I0-1tAK
java代码: L/yaVU{aEb
p-xd k|'[
GV5qdD(
/*Created on 2005-6-17*/ `Ug tvo
package com.adt.action.user; ~ltg
h,t:]
import java.util.List; myIe_k,F
d*2u}1Jo8
import org.apache.commons.logging.Log; ALXTR%f
import org.apache.commons.logging.LogFactory; ^^U%cu Kg
import org.flyware.util.page.Page; -%,"iaO
N'QqJe7Z
import com.adt.bo.Result; 5]d{6Nc3P
import com.adt.service.UserService; &?y7I Pp
import com.opensymphony.xwork.Action; >?I/;R.-
FqZgdmwR
/** LTXz$Z]
* @author Joa [1SMg$@<
*/ [9AM\n>g
publicclass ListUser implementsAction{ k"0;D-lTZ>
RYy,wVh}
privatestaticfinal Log logger = LogFactory.getLog lL0M^Nv
g*J@[y;
(ListUser.class); `eR 7H>I
|55dbL$w
private UserService userService; to`mnp9Z
+rc SL8C
private Page page; /8c&Axuv
.T8K-<R
privateList users; lP3h<j
TH:W#Ot
/* cU8x Upq
* (non-Javadoc) ~*-qX$gr
* cG_Vc[
* @see com.opensymphony.xwork.Action#execute() y}"7e)|t%
*/ i\Wdo/c-H
publicString execute()throwsException{ :FHA]oec1
Result result = userService.listUser(page); !OAvD#
page = result.getPage(); WD.U"YI8y
users = result.getContent(); W5 ec
return SUCCESS; *x(Jq?5O7X
} Ch5+N6c^
g7n"
/** x?sI;kUw8
* @return Returns the page. qZ+H5AG2
*/ Q2QY* A
public Page getPage(){ 3CZS)
return page; s&Yi 6:J
} sn{tra
d5!!Ut
/** N+g@8Q2s;5
* @return Returns the users. RUo9eQIPD
*/ %l!xkCKA
publicList getUsers(){ lr3mE
return users; SSA W52xC
} D/ Dt
:YO@_
/** i$uN4tVKT
* @param page [*4fwk^
* The page to set. @S3f:s0~D
*/ 1[PMDS_X
publicvoid setPage(Page page){
QG3&p<
this.page = page; {C3Y7<
} bF-"tm
eV};9VJ$F
/** EgM*d)X
* @param users `I;F$ `\
* The users to set. ] d?x$>
*/ 8e2?tmWM
publicvoid setUsers(List users){ zT9JBMNE:
this.users = users; \'v(Xp6
} 7Y( 5]A9=
E"PcrWB&
/** MMQ;mw=^]
* @param userService B[o`k]]
* The userService to set. /-M@[p&
*/ WO*9+\[v
publicvoid setUserService(UserService userService){ ajH"Jy3A
this.userService = userService; UKBJ_r
} 1vevEa$
} Ol/N}M|3
#JW+~FU`
L}k/9F.5
~mp0B9L%
uGP(R=H
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, 'MxSd( T
=
+9A\HQ|22
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 kLP0{A
_^ |2}t
么只需要: dp5cDF}l
java代码: ;0%OB*lcgE
gzn^#3 b
^+|De}`u
<?xml version="1.0"?> k;^
:
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork {S.>BXX
mTDVlw0dh
1.0//EN" "http://www.opensymphony.com/xwork/xwork- *%FA:Y
6"
B%)0
1.0.dtd"> x!<yT?A
t+ Bf#:
<xwork> /bRg?Q
['qnn|
<package name="user" extends="webwork- ]+Ixi o
HL K@xKD<
interceptors"> pox,Im
9J-b6,
<!-- The default interceptor stack name _=XX~^I,
A<MtKb
--> 1R%1h9I4'
<default-interceptor-ref 2@j";+
}FqA ppr
name="myDefaultWebStack"/> }Fb!?['G5
ZI>km?w
<action name="listUser" L@Nu/(pB=
>]D4Q<TY
class="com.adt.action.user.ListUser"> 'fd1Pj9~$
<param 1 jb/o5n;
clO,}Ph>
name="page.everyPage">10</param> !
NV#U
<result d9^E.8p$
3,X/,'
name="success">/user/user_list.jsp</result> E2wz(,@
</action> j7QX,_Q
mu]as: ~
</package> _"a=8a06G
^C)n$L>C0
</xwork> je,}_:7
.^(/n9|o-
%|W.^q
?X$,fQ#F|
sN=6 gCau
mB'3N;~
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 \K2*Q&>
$D1w5o-
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。 BHDML.r }M
]jMKC8uz
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 6=_~0PcY
c7uG9
uYI@9U
I,@r5tKo
ZfAzc6J?\
我写的一个用于分页的类,用了泛型了,hoho )Q;978:
"Y:/=
Gx
java代码: C]u',9,
Q[n\R@
%V!iQzL1
package com.intokr.util; yc;3Id5?>
jR ~DToQ
import java.util.List; 5/><$06rq
sfT+i;p
/** /hW d/H]
* 用于分页的类<br> @r^!{
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 5X.ebd;PT
* Oft arD
* @version 0.01 4p`XG1Pt
* @author cheng -!M,75nU
*/ JNI>VP[c
public class Paginator<E> { 5E\#%K[
privateint count = 0; // 总记录数 fN%jJ-[d
privateint p = 1; // 页编号 qZk'tRv
privateint num = 20; // 每页的记录数 FjfN3#qlg
privateList<E> results = null; // 结果 \kIMDg3}
le)DgIT>=
/** _;9!
* 结果总数 |k 2" _
*/ bKVj [r8D~
publicint getCount(){ 7v}x?I
return count; MhEw
_{?
} 4Cb9%Q0
$P
o}
publicvoid setCount(int count){ q0mOG^
this.count = count; ~,6b_W p/
} 4DWwbO
OKOu`Hz@
/** M(q'%XL^
* 本结果所在的页码,从1开始 _W!p8cB
* 5`[n8mU
* @return Returns the pageNo. G\gMC
<3
*/ :\~+#/=:
publicint getP(){ 34|a\b}
return p; #Doq P:
} K ?$#ntp
J'mDU
/** gYop--\14]
* if(p<=0) p=1 4\5uY
* `\Ku]6J]5
* @param p VObrlOkp
*/ 2GmpCy`L"
publicvoid setP(int p){ #_
C
if(p <= 0) 9 t
n!t
p = 1; &:B<Q$g#
this.p = p; ~3h-j K?
} 8[%Ao/m
,SlN zR
/** JOnyrks
* 每页记录数量 "O>n@Q|
*/ I,6/21kO
publicint getNum(){ $K~LM8_CKy
return num; Tsb{25`+
} u~zs*
qp
_A_ A$N~9
/** DrW#v-d
* if(num<1) num=1 6$ Q,Y}j
*/ #b0{#^S:
publicvoid setNum(int num){ g\oSG)
if(num < 1) eEc4bVQa
num = 1; :B*}^g
this.num = num; w*j$uW6{
} CENVp"C/`
}_.:+H!@
/** ']6VB,c`
* 获得总页数 )4Q?aMm
*/ bJr[I
publicint getPageNum(){ #:fQ.WWO
return(count - 1) / num + 1; A^fjfa);V
} Q'apG)0I
9|'B9C
/** Y o0FUj
* 获得本页的开始编号,为 (p-1)*num+1 I XA>`D
*/ ;a"q'5+Ne
publicint getStart(){ 0CvsvUN@
return(p - 1) * num + 1; -l+P8:fL~
} R/b4NGW@
8Q`WB0E<|
/** EEy$w1ec
* @return Returns the results. 1-SVCk
-
*/ i hL/n
publicList<E> getResults(){ 4NEq$t$Jn
return results; >v;8~pgO
} {WN(&eax
@# P0M--X
public void setResults(List<E> results){ {xcZ*m!B
this.results = results; D.!~dyI.,$
} > Vb@[
G*
%t'jX9
public String toString(){ dP$GThGl
StringBuilder buff = new StringBuilder ^:, l\Y
3{Nbp
(); 2pHR_mrb
buff.append("{"); z~6y+
buff.append("count:").append(count); Upl6:xYrG
buff.append(",p:").append(p); T4e\0.If
buff.append(",nump:").append(num); zkM"cb13q/
buff.append(",results:").append FwKj+f"
!4@G3Ae22
(results); #PvB/3
buff.append("}"); _gNz9$S
return buff.toString(); PrQ?PvA<L
} 4S0>-?{
}]1BO
} f}c\_}(
zZ-wG
f67NWFX