Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Yv;iduc('
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 !"^//2N+,
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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 y#{> tC
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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 'k$j^|r>
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分页支持类: r/ LgmVRn
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java代码: ^X?3e1om
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package com.javaeye.common.util; P_c9v/
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import java.util.List; _E[)_yH'-
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publicclass PaginationSupport { SxRa?5
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publicfinalstaticint PAGESIZE = 30; *+cW)klm
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privateint pageSize = PAGESIZE; %,5_]bGvb
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privateList items; 8DJoQl9
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privateint totalCount; t'Pn*
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privateint[] indexes = newint[0]; n#5%{e>
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privateint startIndex = 0; FAd4p9[Y
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public PaginationSupport(List items, int $>PV6
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totalCount){ |Xk>a7X
setPageSize(PAGESIZE); odpjEeQC
setTotalCount(totalCount); |`6*~ciUV
setItems(items); H(j983
setStartIndex(0); 0W>,RR)
} DlbNW& V
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public PaginationSupport(List items, int L(qQ,1VY
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totalCount, int startIndex){ 0h~7"qUF@
setPageSize(PAGESIZE); L,wEUI
setTotalCount(totalCount); jG&gd<^
setItems(items); (\NZ)Ys
setStartIndex(startIndex); Bgj^n{9x
} <MBpV^Y}
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public PaginationSupport(List items, int a{7'qmN1
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totalCount, int pageSize, int startIndex){ YeCS`IXm
setPageSize(pageSize); s:\FlQ0
setTotalCount(totalCount); x.~A vJ
setItems(items); }0~4Z)?e3
setStartIndex(startIndex); x\R
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} m'.y,@^B
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publicList getItems(){ mXXU{IwUe
return items; |.Y}2>{
} "_
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publicvoid setItems(List items){ Z]1jg>")
this.items = items; hUGP3ExC*
} }&O}t{gS*
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publicint getPageSize(){ /V@9!
return pageSize; {]6Pd`-
} _B5vh(.
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publicvoid setPageSize(int pageSize){ m_g2Cep
this.pageSize = pageSize; \bPSy0
} m3E`kW|
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publicint getTotalCount(){ 7[?{wbq
return totalCount; "nEfk{ g
} <*55d2
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publicvoid setTotalCount(int totalCount){ G :JQ_w
if(totalCount > 0){ [=q&5'FY0
this.totalCount = totalCount; R-V4Ju[:
int count = totalCount / w5uOkz #
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pageSize; (Ld,<!eN0
if(totalCount % pageSize > 0) 0<C]9[l
count++; p`-Oz]
indexes = newint[count]; 2/m4|
for(int i = 0; i < count; i++){ (B:+md\Q
indexes = pageSize * !m<v@SmL\
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} :@8N${7`$A
}else{ 14
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this.totalCount = 0; VHihC]ks,
} i~0x/wSl_
} 3"HW{=
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publicint[] getIndexes(){ H%z9VJ*!0
return indexes; waI:w,
} 'Wz`P#/
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publicvoid setIndexes(int[] indexes){ zt|DHVy
this.indexes = indexes; g ONybz6]
} ;S.o`z1GI
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publicint getStartIndex(){ .ZK^kcyA
return startIndex; s7>a
} A4>j4\A[M
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publicvoid setStartIndex(int startIndex){ P/XCaj3a[
if(totalCount <= 0) 'V#$PZx
this.startIndex = 0; zo>@"uH4
elseif(startIndex >= totalCount) %ot4$eY
this.startIndex = indexes j| Hyv{sM
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[indexes.length - 1]; 9 m`VIB
elseif(startIndex < 0) ]]^eIjg>a6
this.startIndex = 0; 6k-
else{ n/Fx2QC{
this.startIndex = indexes l}MVk%[
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[startIndex / pageSize]; Qf#=Y j
} '`nf7b(
} 0Mu6R=s
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publicint getNextIndex(){ ziTE*rNJ
int nextIndex = getStartIndex() + sRkPXzK
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pageSize; tEFbL~n
if(nextIndex >= totalCount) > t~2
return getStartIndex(); L }L"BY3$
else J,Rp&tavt:
return nextIndex; O
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} &A!?:?3%O
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publicint getPreviousIndex(){ [wv;CUmgc
int previousIndex = getStartIndex() - eWWtMnq
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pageSize; sRKoM
if(previousIndex < 0) e[l#r>NT
return0; ,|G~PC8
else >o,l/#z
return previousIndex; 1 ` ={**
} VteMsL/H
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} N,ysv/zq7
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抽象业务类 :F`-<x/
java代码: c>.=;'2
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/** #L`'<ge'g*
* Created on 2005-7-12 %s*F~E
*/ ZXH{9hxd
package com.javaeye.common.business; yp
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import java.io.Serializable; -ztgirU
import java.util.List; s)9d\{
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import org.hibernate.Criteria; 6O\a\z
import org.hibernate.HibernateException; sX[k}=HCK
import org.hibernate.Session; -a\[`JHi
import org.hibernate.criterion.DetachedCriteria; !}I+)@~\w
import org.hibernate.criterion.Projections;
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import ]Mb:zs<r
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org.springframework.orm.hibernate3.HibernateCallback;
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import 'Hv=\p4$1
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org.springframework.orm.hibernate3.support.HibernateDaoS y^[?F>wB
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upport; L <W2a(
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import com.javaeye.common.util.PaginationSupport; ywY[g{4+
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public abstract class AbstractManager extends ,
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HibernateDaoSupport { < VrHWJo
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privateboolean cacheQueries = false; &3CC |
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privateString queryCacheRegion; @5tGI U;1
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publicvoid setCacheQueries(boolean p,K!'\
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cacheQueries){ \#7@"~<
this.cacheQueries = cacheQueries; J-5E# v
} eJ+@<+vr;x
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publicvoid setQueryCacheRegion(String }UX0 eI4
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queryCacheRegion){ T%O2=h\} E
this.queryCacheRegion = Bv{DZ?{s
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queryCacheRegion; &ieb6@RO`Q
} " 3tk"#.#
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publicvoid save(finalObject entity){ :R1F\FT*
getHibernateTemplate().save(entity); J. $U_k
} 2F#DJN#
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publicvoid persist(finalObject entity){ 8fWk C<f}
getHibernateTemplate().save(entity); \V%l.P4>e
} A Qm!7,
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publicvoid update(finalObject entity){ D]'/5]~z<
getHibernateTemplate().update(entity); rcUJOI
} $A^OP{
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publicvoid delete(finalObject entity){ |3P dlIbO
getHibernateTemplate().delete(entity); 0P l>k'9
} 7p_B?r
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publicObject load(finalClass entity, 4_W*LG~2s
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finalSerializable id){ 6H^=\
return getHibernateTemplate().load OJT%?P%@{
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(entity, id); :rSCoi>K
} Rj!9pwvT
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publicObject get(finalClass entity, >SW c
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finalSerializable id){ =-E%vnU
return getHibernateTemplate().get jL,P )TC
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(entity, id); g).IF.
} 0JU+v:J[=
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publicList findAll(finalClass entity){ o]TKL'gW
return getHibernateTemplate().find("from 0S#T}ITm4Z
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" + entity.getName()); *('Vyd!n
} i;fU],aK!
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publicList findByNamedQuery(finalString ub9,Wd"^
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namedQuery){ :=?od
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return getHibernateTemplate 9s&dN
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().findByNamedQuery(namedQuery); N?v}\ PU
} MnTqWC90
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publicList findByNamedQuery(finalString query, gt\*9P
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finalObject parameter){ y`a]##1j$M
return getHibernateTemplate -Ra-Ux
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().findByNamedQuery(query, parameter); v~:'t\n
} j2s{rQQ
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publicList findByNamedQuery(finalString query, GQ6~Si2
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finalObject[] parameters){ ~n;U5hcB
return getHibernateTemplate En{<
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().findByNamedQuery(query, parameters); ImsyyeY]
} ypWhH
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publicList find(finalString query){ NX8.
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return getHibernateTemplate().find _18Aek
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(query); {sF;R.P&r
} ODKHI\U
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publicList find(finalString query, finalObject !@[@&.
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parameter){ *T2kxN,Ik
return getHibernateTemplate().find 7Cx-yv
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(query, parameter); 51 "v`O+
} o[aIQ|G
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public PaginationSupport findPageByCriteria .#LvvAeh
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(final DetachedCriteria detachedCriteria){ B4{F)Zb
return findPageByCriteria &
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 6ag0c&k
} ~\u~>mtchu
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public PaginationSupport findPageByCriteria juB /?'$~
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(final DetachedCriteria detachedCriteria, finalint E=]$nE]b
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startIndex){ WDF6.i ?
return findPageByCriteria x.>&|Ej
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(detachedCriteria, PaginationSupport.PAGESIZE, HXgf=R/$
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startIndex); z-m:l;
} p4@0Dz`Q
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public PaginationSupport findPageByCriteria LfMN 'Cb
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(final DetachedCriteria detachedCriteria, finalint Erm]uI9`
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pageSize, +\RviF[+
finalint startIndex){ ql7N\COoq
return(PaginationSupport) &IP`j~b
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getHibernateTemplate().execute(new HibernateCallback(){ l} W">
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publicObject doInHibernate $fwj8S7$
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(Session session)throws HibernateException { ggUw4w/e
Criteria criteria = :.crES7<[X
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detachedCriteria.getExecutableCriteria(session); +T HBPEq
int totalCount = , RU
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((Integer) criteria.setProjection(Projections.rowCount o"g<Vz
3 +8{Y
()).uniqueResult()).intValue(); ?'U@oz8 B
criteria.setProjection y6&o+;I$[
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(null); 9PG3cCr?
List items = (t"e#b(:
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criteria.setFirstResult(startIndex).setMaxResults 7W=s.Gy7G\
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(pageSize).list(); UQq Qim
PaginationSupport ps = 6OZn7:)Y
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Q}
new PaginationSupport(items, totalCount, pageSize, KP CZiu7
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startIndex); Thuwme
return ps; ?GGBDql
} .=@CF8ArG
}, true); A>rN.XW
} 3-_`x9u*
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public List findAllByCriteria(final h%] D[g
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DetachedCriteria detachedCriteria){ v
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return(List) getHibernateTemplate xd!GRJ<I
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().execute(new HibernateCallback(){ p5#UH
publicObject doInHibernate E2Ec`o
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(Session session)throws HibernateException { s}?QA cC
Criteria criteria = 8[x{]l[
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detachedCriteria.getExecutableCriteria(session); v4r%'bA
return criteria.list(); ms#|Yl1/|
} I]Vkaf I>(
}, true); a>#]d
} _^p\
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public int getCountByCriteria(final EO"G(v
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DetachedCriteria detachedCriteria){ U?j[
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Integer count = (Integer) >uwd3XW5
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getHibernateTemplate().execute(new HibernateCallback(){ 3u4P
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publicObject doInHibernate bEb+oRI
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(Session session)throws HibernateException { nw=:+?
Criteria criteria = `FmRoMW9+
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detachedCriteria.getExecutableCriteria(session); :)kWQQ+,
return vpoJ{TPO
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criteria.setProjection(Projections.rowCount dyt.(2
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()).uniqueResult(); ,Ofou8C6
} !$#8Z".{v{
}, true); P.kf|,8L
return count.intValue(); v(^;%
} &W
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用户在web层构造查询条件detachedCriteria,和可选的 )
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 hv )d
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PaginationSupport的实例ps。 ]
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ps.getItems()得到已分页好的结果集 6 IKi*}
ps.getIndexes()得到分页索引的数组 I~25}(IDZ"
ps.getTotalCount()得到总结果数 ]_2<uK}fg
ps.getStartIndex()当前分页索引 r-5xo.J'
ps.getNextIndex()下一页索引 _Q}vPSJviC
ps.getPreviousIndex()上一页索引 #fxdZm,
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 e.]k4K
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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 =8EGB\P
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一下代码重构了。 [W=6NAd
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我把原本我的做法也提供出来供大家讨论吧: ig4mj47wJ
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首先,为了实现分页查询,我封装了一个Page类: [wcp2g3Px
java代码: ;D}E/'=
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/*Created on 2005-4-14*/ PRN%4G
package org.flyware.util.page; e# KP3Lp
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/** TTz_w-68
* @author Joa [+b&)jN*2
* P;ovPyoO
*/ DaqpveKa
publicclass Page { F,JqHa9
t8t+wi!
/** imply if the page has previous page */ "^5 %g%
privateboolean hasPrePage; :tX,`G
{\ J%i|u
/** imply if the page has next page */ JmbWEX|
privateboolean hasNextPage; =7-@&S=?s
d.p%jVO)"
/** the number of every page */ dA$qzQ
privateint everyPage; K"VRHIhfg
|%fM*F^7/
/** the total page number */ 6='x}Qb \H
privateint totalPage; #)( D_*
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/** the number of current page */ 9^^:Y3j
privateint currentPage; qfyuq]
8Oo16LPD
/** the begin index of the records by the current ^q/_D%]C
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query */ }RZN3U=
privateint beginIndex; "SU
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/** The default constructor */ L*1yK*
public Page(){ </|m^$v
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} >e QFY^d5
O8 5) ^
/** construct the page by everyPage Y$ '6p."=
* @param everyPage o7v,:e:
* */ B-[qS;PY%
public Page(int everyPage){ qp2&Z8S\D
this.everyPage = everyPage; Vnnl~|Xx
} O
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/** The whole constructor */ q 1+{MPJ
public Page(boolean hasPrePage, boolean hasNextPage, 4_h?E:sBb
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int everyPage, int totalPage, yn.f?[G2
int currentPage, int beginIndex){ VU\{<j{
this.hasPrePage = hasPrePage; X&cm)o%5Fe
this.hasNextPage = hasNextPage; g)^g_4
this.everyPage = everyPage; M]A!jWtE
this.totalPage = totalPage; YCo qe,5
this.currentPage = currentPage; }Z8DVTpX}
this.beginIndex = beginIndex; GA2kg7
} H]VoXJ\*
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/** +cC$4t0$^A
* @return P6u%-#
* Returns the beginIndex. rjL4t^rT
*/ |M(0CYO
publicint getBeginIndex(){ Ep1p>s^
return beginIndex; [PL]!\NJ
} YH'j"|{
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/** @Jr@
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* @param beginIndex ?a'P;&@7
* The beginIndex to set. \Qei}5P,
*/ z-?WU
publicvoid setBeginIndex(int beginIndex){ c_FnJ_+ +f
this.beginIndex = beginIndex; & _mp!&5XV
} 7aJ:kumDZ
UGK,+FN
/** oE'Flc.
* @return =x}p>#o,J
* Returns the currentPage. Qi\"b
*/ 8d8GYTl b)
publicint getCurrentPage(){ KN"<f:u
return currentPage; ZMmf!cKY:'
} "E%3q 3|"l
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/** c^`(5}39v
* @param currentPage w4j,t
* The currentPage to set. NLF6O9
*/ R6-Z]Hu
publicvoid setCurrentPage(int currentPage){ _/cL"Wf
this.currentPage = currentPage; {}N=pL8MS
} T/TMi&:?.
_A,mY6*
/** {qL}:ha?
* @return i=X
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* Returns the everyPage. ::2(pgH
*/ \wxLt}T-Q
publicint getEveryPage(){ -9^A,vX
return everyPage; @V qI+5TA
} #qg(DgH
7
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/** pX]"^f1?O
* @param everyPage >0.a#-u^
* The everyPage to set. ?$ 0t @E
*/ 8 ;o*c6+
publicvoid setEveryPage(int everyPage){ l[M?"<Ot;
this.everyPage = everyPage; Gey j`t
} ~<q^4w.=7C
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/** ^ 9 FRI9?
* @return kyu
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* Returns the hasNextPage.
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*/ l|5;&(Y+s
publicboolean getHasNextPage(){ 6>j0geFyE2
return hasNextPage; to#N>VfD
} fE,Io3
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-{
/** Jj,fdP#\
* @param hasNextPage hvOl9W>
* The hasNextPage to set. I#9q^,,F
*/ *W$bhC'w
publicvoid setHasNextPage(boolean hasNextPage){ NAh^2X
this.hasNextPage = hasNextPage; K5EU?J&
} eGQ-Ht,N
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/** N=~aj7B%
* @return .ly K
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* Returns the hasPrePage. ZOY zCc(d
*/ GLr7sack
publicboolean getHasPrePage(){ (V9 ;
return hasPrePage; b?nORWjC
} ^2-t|E=
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/** ,8Q&X~$rY
* @param hasPrePage )l[bu6bM
* The hasPrePage to set. g0>Q* x
*/ ?<6yKxn
publicvoid setHasPrePage(boolean hasPrePage){ XG}9)fT
this.hasPrePage = hasPrePage; =9L1Z \f
} %)p?&_
OO*2>Qy~z
/** p~f=0K
* @return Returns the totalPage. ^F:Bj&0v[
* k`h#.B J
*/ ^!sIEL
publicint getTotalPage(){ #MAXH7[
return totalPage; 5Sz}gP('
}
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/** ^b^}6L'Z
* @param totalPage ]1&}L^a
* The totalPage to set. 9N V.<&~
*/ p d(W(-`8!
publicvoid setTotalPage(int totalPage){ oxXCf%!
this.totalPage = totalPage; $c }-/U 8
} #8@o%%Fd
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} a<CACWsN.T
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 }0~X)Vgm(
2VaKt4+`
个PageUtil,负责对Page对象进行构造: qA5 Ug
java代码: ^/fasl$#
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/*Created on 2005-4-14*/ {pk]p~
package org.flyware.util.page; )SyU
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import org.apache.commons.logging.Log; O#?@'1
import org.apache.commons.logging.LogFactory;
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{
/** tQ(4UHqa~
* @author Joa 5]~451
* oMHTB!A=2
*/ 6QAhVg: A
publicclass PageUtil { ppzQh1
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privatestaticfinal Log logger = LogFactory.getLog a6!|#rt
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(PageUtil.class); D`3`5.b
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/**
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* Use the origin page to create a new page ~Xz?H=}U+
* @param page v W4n>h}]
* @param totalRecords AL;4-(KH
* @return %uDH_J|^
*/ "NtY[sT{V
publicstatic Page createPage(Page page, int R*DQLBWc
7>
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totalRecords){ 58P[EMhL
return createPage(page.getEveryPage(), il% u)NN
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page.getCurrentPage(), totalRecords); d
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} o>\o=%D.a
pD;fFLvN
/** :f~qt%%/
* the basic page utils not including exception }/2M?W0
# p2`9o
handler *" +u^
* @param everyPage ZQ{-6VCjl
* @param currentPage {A'_5 X9
* @param totalRecords iTVZo?lVo
* @return page H{hzw&dZ<P
*/ YO9;NA{sH
publicstatic Page createPage(int everyPage, int _$i)bJ
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currentPage, int totalRecords){ ^09-SUl^
everyPage = getEveryPage(everyPage); Q2[;H!"
currentPage = getCurrentPage(currentPage); 7=gcdfW,;x
int beginIndex = getBeginIndex(everyPage, UCJx{7
9_fbl:qk;\
currentPage); p0hE`!
int totalPage = getTotalPage(everyPage, bE?X?[K
&O#,"u/q`
totalRecords); |#yH,f
boolean hasNextPage = hasNextPage(currentPage, .FG%QF F~
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totalPage); JJK-+a6cX
boolean hasPrePage = hasPrePage(currentPage); Rqr>B(|
rFaG-R
returnnew Page(hasPrePage, hasNextPage, ty'/i!/\
everyPage, totalPage, 2'u%
currentPage, fZrh_^yH
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beginIndex); Kc,i$FH
} ~G 3txd
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privatestaticint getEveryPage(int everyPage){ 8N \<o7t%
return everyPage == 0 ? 10 : everyPage; mM:%-I\$
} -e"A)Bpl(
:kFPPx?
privatestaticint getCurrentPage(int currentPage){ w[C*w\A\M
return currentPage == 0 ? 1 : currentPage; E+lr{~
} RFoCM^
?tA%A
privatestaticint getBeginIndex(int everyPage, int f-p$4%(
-iKoQkHt
currentPage){ _s*p$/V\
return(currentPage - 1) * everyPage; .><-XJ
} -Aojk8tc
D -d
privatestaticint getTotalPage(int everyPage, int x#gZC1$Y
nW}jTBu_K+
totalRecords){ i%[+C
int totalPage = 0; [+Fajo;0
a~ dgf:e`
if(totalRecords % everyPage == 0) !o1IpTN
totalPage = totalRecords / everyPage; 83 <CDjD
else TD%&9$F
totalPage = totalRecords / everyPage + 1 ; )Xa_ry7
05g %5vHF
return totalPage;
sC0u4w>Y
} Ho =vdB
U$Z<lx2P
privatestaticboolean hasPrePage(int currentPage){ 7Mk>`4D'c
return currentPage == 1 ? false : true; #ID
fJ2
} ) J.xQ}g
"=1gA~T
privatestaticboolean hasNextPage(int currentPage, VXW*LEk
p]ujip
int totalPage){ (;&}\OX6nm
return currentPage == totalPage || totalPage == KIp^|
k7>
'~
H`Ffd.
0 ? false : true; 3dlY_z=0
} NGJst_
Q6D>(H#"0
,H%[R+)
} {2YqEX-I*
%}e['d h
r8?p6E
4.^T~n G
#:By/9}-
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。 xy
b=7
mP Hto-=fB
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 c@Br_-
.$7RF!p
做法如下: ]YtN6Rq/
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ~_Fx2T:X
?dbSm3
的信息,和一个结果集List: J/Lf(;C_
java代码: L]8z6]j*
4\5i}MIS0
J]#rh5um
/*Created on 2005-6-13*/ Z,O*p,Gzn
package com.adt.bo; FzcXSKHV%
0|.jIix;
import java.util.List; ^b$_I31D
(qvH=VTwP
import org.flyware.util.page.Page; jXLd#6
o$eCd{HuX
/** ;mT}Q;F#
* @author Joa q/@+.q
*/ $}{[_2
publicclass Result { Vjs'|%P7
n~]"sTC}&
private Page page; &bz% @p;
}I-nT!D'y
private List content; 3}!u8,P
"w%:5~u9
/** pS|K[:5
* The default constructor ;N?(R\*8
*/ (WJ)!
public Result(){ <D3mt Q
super(); \8=)X} )
} T- _))
rhcax%Cd
/** 5a'`%b{{
* The constructor using fields NLK1IH#
* T[)!7@4r
* @param page ,h*N9}xYTi
* @param content rJkJ/9s
*/ :\JCxS=EW
public Result(Page page, List content){ \
a,}1FS
this.page = page; m$=}nI(H
this.content = content; ;Mo_B9
} Zp3-Yo w2
>h)kbsSU0z
/** !u@P\8M}
* @return Returns the content. |T$?vIG[
*/ g(9* !g
publicList getContent(){ uxB)dS
return content; ~abyjM
} Yj1|]i5b
X=KW
>
/** ^)?Wm,{"w
* @return Returns the page. Te
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*/ N|$9v{ j_
public Page getPage(){ ~ HhB@G!3
return page; #Zw:&'
QB
} Bh'fkW3
@,GL&$Y:W
/** :>JfBJ]|
* @param content P*BRebL:
* The content to set. lYCvYe
*/ 7)V"E-6h
public void setContent(List content){ 'I&0$<
this.content = content; F5RL+rU(h
}
,AweHUEn
d}zh.O5P!
/** ^n0;Q$\
* @param page <O
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* The page to set. XQ9W
y
*/ V%s7*`U
publicvoid setPage(Page page){ )f|`mM4DW!
this.page = page; +1YEOOfVY
} OyVP_Yx,V
} Lo1ySLo$G
;W|NG3_y
05R"/r*
myR{}G
H" `'d
2. 编写业务逻辑接口,并实现它(UserManager, ;7qIm83
38p"lT
UserManagerImpl) G9^`cTvv'8
java代码: Z! O4hA4
M,_
$s,
G|KA!q
/*Created on 2005-7-15*/ !i~(h&z
package com.adt.service; G|f9l?p
cVW7I
import net.sf.hibernate.HibernateException; BYX c
'K
Zh;wQCDj
import org.flyware.util.page.Page; }W8A1-UF
B6
(\1
import com.adt.bo.Result; 0>Snps3*Z
.)b<cH~%
/** (cOe*>L;
* @author Joa |Q3d7y
*/ &L$9Ii
publicinterface UserManager { zp;!HP;/=
1*u]v{JJ(
public Result listUser(Page page)throws 7Dbm
s(:(
]|tg`*l!>
HibernateException; O*l,&5
}x`Cnn
} @@H_3!B%4v
GNMOHqg4
[w'Q9\,p
|-}.Y(y
NplyvjQN;
java代码: &M}X$k I
?'TK~,dG/
isL
zgN%
/*Created on 2005-7-15*/ q7Hf7^a
package com.adt.service.impl; _x<NGIz
g77M5(ME
import java.util.List; sQ#e 2
=0d|F
8
import net.sf.hibernate.HibernateException; n8<?<-2
9)1Ye
import org.flyware.util.page.Page; j+gxn_E
import org.flyware.util.page.PageUtil; =|z:wlOs
;zJb("n
import com.adt.bo.Result; hU""YP~y
import com.adt.dao.UserDAO; 9KU&M"Yq&i
import com.adt.exception.ObjectNotFoundException; /ovVS6Ai
import com.adt.service.UserManager; d-_V*rYU
X?'cl]1?
/** _M`ZF*o=c
* @author Joa :,0(aB
*/ ~r.R|f]IQ
publicclass UserManagerImpl implements UserManager { (L*GU 7m;
~gd#cL%
private UserDAO userDAO; Y 3ApW vS
!{.CGpS ]
/** I@KM2KMN
* @param userDAO The userDAO to set. C K7([>2
*/ gQ{ #C'
publicvoid setUserDAO(UserDAO userDAO){ rpRyB9
this.userDAO = userDAO; v;<gCzqQh
} sr6BC.
{h+8^
/* (non-Javadoc) Y.Zd_,qy
* @see com.adt.service.UserManager#listUser |&= -Nm
2nkA%^tR
(org.flyware.util.page.Page) =8T!ldVxES
*/ nv:Qd\UM
public Result listUser(Page page)throws v]V N'Hs?
k\ #;
HibernateException, ObjectNotFoundException { RJWO h
int totalRecords = userDAO.getUserCount(); w1)TnGT
if(totalRecords == 0) 9i5?J ]o^
throw new ObjectNotFoundException (lM,'
X
61|:E
("userNotExist"); 9S|sTf
page = PageUtil.createPage(page, totalRecords); [nO3%7t@
List users = userDAO.getUserByPage(page); $K^l=X
returnnew Result(page, users); #h[>RtP:
} (I}owr 5:
w[-)c6J yE
} wN!\$i@E:
P?h1nxm`'
T/'z,,Y
z,TH}s6
QXZXj#`
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 jU&m*0nL
f#!+l1GV
询,接下来编写UserDAO的代码: z^QrIl/<c2
3. UserDAO 和 UserDAOImpl: n?@zp<
java代码: Rs<q^w]
Qfn:5B]tI
#<*.{"T
/*Created on 2005-7-15*/ s?EQ
package com.adt.dao; -O *_+8f
9!_,A d;3
import java.util.List; !XtG6ON=
r1r$y2v~
import org.flyware.util.page.Page; ?wB_fDb}
3}H{4]*%_
import net.sf.hibernate.HibernateException; ;_bRq:!j;
Uqel
UL}
/** wb.yGfJ
* @author Joa ;W?#l$R
*/ RK!9(^Ja
publicinterface UserDAO extends BaseDAO { 0V~zZ/e
64?HqO
6(
publicList getUserByName(String name)throws "bhK%N;
Nnh\FaI
HibernateException; NuQ!huh
s>J5.Z7"'j
publicint getUserCount()throws HibernateException; F\DiT|?}
VP#KoX85
publicList getUserByPage(Page page)throws C .S BJ
MI`qzC*%
HibernateException;
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nc;eNB
} C1D:Xi-
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rexf#W)
_Xd"'cXw
(.:*GUg
java代码: A] |w1nq
O-V|= t
a}%f+`z
/*Created on 2005-7-15*/ sq2:yt
package com.adt.dao.impl; /2Wg=&H
BXYHJ
import java.util.List; sQ}|Lu9hZ
vu+g65"
import org.flyware.util.page.Page; Ah2 {kK
&gp&i?%X9b
import net.sf.hibernate.HibernateException; i{6&/TBnr
import net.sf.hibernate.Query; VgNB^w
L/ 7AGR|;C
import com.adt.dao.UserDAO; @ual+=L
,4Q4{Tx
/** RzqgN*]lY
* @author Joa -hXKCb4YU
*/ T aS1%(
public class UserDAOImpl extends BaseDAOHibernateImpl F{ %*(U
@U_CnhPQq
implements UserDAO { ef`_
n+`
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/* (non-Javadoc) d=vuy
* @see com.adt.dao.UserDAO#getUserByName G<7M;vRvP
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(java.lang.String) L?h?LZnq
*/ fxd+0R;f
publicList getUserByName(String name)throws '[WL8,.Q
~X3g_<b_8
HibernateException { F}}!e.>c
String querySentence = "FROM user in class #yH+ENp0
=de'Yy:\-
com.adt.po.User WHERE user.name=:name"; ]6e(-v!U
Query query = getSession().createQuery Jc#D4e1#
76tn`4NIP
(querySentence); eUy*0
query.setParameter("name", name); %R>n5m
return query.list(); 1Vu#:6%
} , -Hj
"Pwa}{
/* (non-Javadoc) 5GM-*Ak @
* @see com.adt.dao.UserDAO#getUserCount() wyy
1M+
*/ !h.hJt
publicint getUserCount()throws HibernateException { HV~Fe!J_
int count = 0; xxur4@p!
String querySentence = "SELECT count(*) FROM 8oJl ]
y >=Y
user in class com.adt.po.User"; uN)c!='I
Query query = getSession().createQuery o-rX 4=T
7+P;s,mi7
(querySentence); Wq4<9D
count = ((Integer)query.iterate().next s`$}xukT
&3t973=
()).intValue(); i"<W6
return count; (\F9_y,6*\
} 1b%Oi.;
Cx2#
0$
/* (non-Javadoc) tczJk1g}
* @see com.adt.dao.UserDAO#getUserByPage bA)nWWSg=
[OCjYC`
(org.flyware.util.page.Page) e{E\YEc
*/ ]Kt@F0U<o
publicList getUserByPage(Page page)throws osXEzr(
Vkg0C*L_
HibernateException { q}t]lD
%C
String querySentence = "FROM user in class @:?[R&`
LTe ({6l0
com.adt.po.User"; gF,=rT1:>r
Query query = getSession().createQuery m54>}
%>&ex0j]
(querySentence); +mWf$+w
query.setFirstResult(page.getBeginIndex()) @S@VsgQ%3Z
.setMaxResults(page.getEveryPage()); M 2hZ'
return query.list(); xqX3uq
} A`uHZCwJ5
r
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{
} JN/=x2n.
UfX~GC;B
K) }1;
WAxNQfEe
X<,QSTP
至此,一个完整的分页程序完成。前台的只需要调用 }[akj8U
#KiJ{w'
userManager.listUser(page)即可得到一个Page对象和结果集对象 gO8d2?Oh
BzfR8mD
的综合体,而传入的参数page对象则可以由前台传入,如果用 BaQyn 6B
E4% -*n
webwork,甚至可以直接在配置文件中指定。 uA#K59E+
[\W&
下面给出一个webwork调用示例: 4H6Fq*W{k
java代码: qKD
vL@<l^`$0
`0qjaC
/*Created on 2005-6-17*/ A1prYD
package com.adt.action.user; s6~;)(r
a>OYJe
import java.util.List; Br!;Ac&N
HS<Jp44
import org.apache.commons.logging.Log; )Jjp^U3Ub
import org.apache.commons.logging.LogFactory; 7Vy_Cec1
import org.flyware.util.page.Page; u1 Q;M`+>
+ALrHFG
import com.adt.bo.Result; @/:4beh
import com.adt.service.UserService; ~s+vJvWz
import com.opensymphony.xwork.Action; )7 & -DI1
e;`(*
/** zu1"`K3b
* @author Joa TO.b-
;
*/ b1?^9c#0d
publicclass ListUser implementsAction{ ?(gha
T#qf&Q Z
privatestaticfinal Log logger = LogFactory.getLog ,Wd=!if
VZt%cq
(ListUser.class); e8<}{N0,n
HF*0
private UserService userService; [P+kQBLpL
Q#3}AO
private Page page; @4y?XL(n
,cNe-KJk
privateList users; ',R%Q0Q
|J!mM<*K
/* $sY'=S
* (non-Javadoc) h\[@J rDa
* a=}1`Q
* @see com.opensymphony.xwork.Action#execute() uLzE'ZmV
*/ JPZp*5c6A
publicString execute()throwsException{ n$C-^3c
Result result = userService.listUser(page); nriSVGi
page = result.getPage(); OdFF)-K>~
users = result.getContent(); i(|ug_^
return SUCCESS; a(vt"MQ_
} rNk'W, FU
#r #[&b
/** ]jD\4\M}
* @return Returns the page. /O:4u_
*/ -rU_bnm
public Page getPage(){ \OVFZ D
return page; Z5'^81m$o
} ~
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1Of(O!
/** f,yl'2{
* @return Returns the users. RyK~"CWT
*/ |p/*OFC6
publicList getUsers(){ /p<9C?
return users;
`o#(YEu
} l+6c|([
8e-nzc,]
/** A8.noV
* @param page 6m$X7;x}
* The page to set. <KX9>e
*/ LY0f`RX*&
publicvoid setPage(Page page){ Ibz9juY
this.page = page; yo[Sh6r/9b
} |^-D&C(Eu
N~flao^
/** Nqj@p<y/q
* @param users 4 *}H3-`
* The users to set. vCi`htm%
*/ zH~P-MqC
publicvoid setUsers(List users){ 6agq^wI
this.users = users; 6#Z]yk+p
} lPZ>#
FQ4R>@@5
/** n,FyK`x
* @param userService o:{Sws(=
* The userService to set. dI\_I]
*/ `:=1*7)?
publicvoid setUserService(UserService userService){ ht%qjE
this.userService = userService; w=XIpWl
} !M8_PC*a
} 4tm%F\Izy
tn$TyCzckW
^>E>\uz0v
~u$cX1M
!U%
|pa
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, 1\(
N,'h
[TA.|7&
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 /!0&b?
Xb:*
KeZq
么只需要: kKlNhP(
java代码: -ZE YzZqY
qfXt%6L
{{G3^ysa
<?xml version="1.0"?> AM=,:k$
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork )ItABl[{
oIO@#
1.0//EN" "http://www.opensymphony.com/xwork/xwork- b\JU%89
F?'
1.0.dtd"> .bY>++CAPA
ZY,$oFdsi
<xwork> 'l(s)Oa{M:
zI[<uvxzW`
<package name="user" extends="webwork- /lR*ab
8a*&,W
interceptors"> P@@MQ[u?!.
*jhgCm
<!-- The default interceptor stack name 'nPI
zK<v
=-Hhm($n
--> .I~:j`K6
<default-interceptor-ref |?J57(
2z{B
name="myDefaultWebStack"/> 4AEw[(t
,oH\rrglf
<action name="listUser" $B?8\>_?
Ee MKo
class="com.adt.action.user.ListUser"> =7e!'cF[
<param Z e>R@rK
P Ptmh. }e
name="page.everyPage">10</param> |a03SZx
<result Lp-$Ie
&ic'!h"
name="success">/user/user_list.jsp</result> 3ux7^au
</action> ^Lb\k|U,\
itNuY<"
</package> Fk49~z
cEa8l~GC<
</xwork> Fy\q>(v.
n@tt.n!{l
xGyl7$J
tW~kn9glZ
+pgHCzwJE
^[SW07o~
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 aPlEM_escS
uxn+.fA
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。 mC@v,"
<xSh13<
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 &-FG}|*4M
=c\(]xX
f|(9+~K/7&
Il4]1d|
MOh&1]2j5
我写的一个用于分页的类,用了泛型了,hoho ~x(|'`
iLv
-*%%
java代码: 3r#['UmT
W*s=No3C
P !f{U;B
package com.intokr.util; ?,7!kTRH
Es#:0KH].v
import java.util.List; '^m'r+B"
vfn[&WN]
/** FVkl#Qy~
* 用于分页的类<br> 5uG^`H@X
* 可以用于传递查询的结果也可以用于传送查询的参数<br> NsYEBT7f
* P9m
* @version 0.01 a$?d_BX
* @author cheng z\<,}x}V
*/ ma-GvWD2
public class Paginator<E> { s@&3;{F6D
privateint count = 0; // 总记录数 VDOC>
privateint p = 1; // 页编号 ,j>FCj>
privateint num = 20; // 每页的记录数 @7"n X
privateList<E> results = null; // 结果 9=$pV==
JAKs [@:
/** 3mofp`e
* 结果总数 nygGI_[l
*/ /-!Fr:Ox>
publicint getCount(){ O)V;na
return count; &8f/ 6dq
} h-"q <eY"
*=B<S/0
publicvoid setCount(int count){ e.L&A|
this.count = count; 4Ia'Yr
} .?CaU
IT= y+
/** HaL'/V~
* 本结果所在的页码,从1开始 Z1
)1s
* BZhf/{h[@
* @return Returns the pageNo. esZhX)dS
*/ 6bs-&Vf
publicint getP(){ lIEZ=CEmY
return p; ms Cz\8Xd
} *
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^!exH(g
/** =9QyOh
* if(p<=0) p=1 \i[N";K
* -[vw 8
* @param p &+02Sn3A
*/ =Bc{0p*
publicvoid setP(int p){ wQ+il6
if(p <= 0) 837:;<T
p = 1; @i'D)6sC
this.p = p; tk-)N+M.
} GIYdI#0RC
!wE% <Fh
/** >pZ_
* 每页记录数量 %"c;kvw
*/ Mu:zWLM*M
publicint getNum(){ ?r(vXq\
return num; &S