Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 r/j:A#6M]o
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 v'W{+>.
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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 h_%q`y ,
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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 heVkCM :
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分页支持类: NKu[6J?)
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java代码: 1<YoGm&
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package com.javaeye.common.util; V`Cyx^P
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import java.util.List; eZ$7VWG#
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publicclass PaginationSupport { o,6t:?Z
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publicfinalstaticint PAGESIZE = 30; ,;$OaJFT
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privateint pageSize = PAGESIZE; 3UZd_?JI[^
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privateList items; w% %q/![uy
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privateint totalCount; im<bo Mv
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privateint[] indexes = newint[0]; M3tl4%j
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privateint startIndex = 0; IO\l8G
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public PaginationSupport(List items, int DrJ?bG;[
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totalCount){ gHg=G+Q@
setPageSize(PAGESIZE); ?I}RX~Tgg
setTotalCount(totalCount); fVbjU1N
setItems(items); $n\P w
setStartIndex(0); p*;!5;OUR
} 'nCVjO7o
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public PaginationSupport(List items, int [wGj?M}
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totalCount, int startIndex){ F@BpAl
setPageSize(PAGESIZE); }`uyOgGg*
setTotalCount(totalCount); Q5,zs_j
setItems(items); cOV j @z
setStartIndex(startIndex); yHeL&H
} J p'^!
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public PaginationSupport(List items, int EXDDUqZ5\
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totalCount, int pageSize, int startIndex){ Ku(YTXtK
setPageSize(pageSize); h^Wb<O`S
setTotalCount(totalCount); zI`I
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setItems(items); [:8\F#KW
setStartIndex(startIndex); e?>
} d_9 Cm@
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publicList getItems(){ FZ"n6hWA
return items; l_g$6\&|
} ~; 9HGtg
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publicvoid setItems(List items){ =:H-9
this.items = items; $vs],C"pX
} Fs/CW\
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publicint getPageSize(){ I,-n[k\J
return pageSize; lw@Yn>eza
} 3&hR#;,"X
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publicvoid setPageSize(int pageSize){ ;_<~9;
this.pageSize = pageSize; ~KK}
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} _{[6hf4p
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publicint getTotalCount(){ )+_Vx}O:}
return totalCount; htBA.eQ
} dyQ7@K.E
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publicvoid setTotalCount(int totalCount){ UG2+Y']
if(totalCount > 0){ Z/Rp?Jz\j/
this.totalCount = totalCount; DbMVbgz<e
int count = totalCount / %2QGbnt_*
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pageSize; @6;OF5VsQ
if(totalCount % pageSize > 0) `<7\Zl
count++; ]Lv P)0=
indexes = newint[count]; S\GWMB!oF
for(int i = 0; i < count; i++){ 8E%LhA.
indexes = pageSize * (TZK~+]@sb
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i; XZE(& (s
} G5}_NS/
}else{ ;hT3N UCA
this.totalCount = 0; )D8op;Fn
} UmR)L!QT8
} 8eXeb|?J
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publicint[] getIndexes(){ q5f QTV
return indexes; "~4V(
} ,=)DykP
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publicvoid setIndexes(int[] indexes){ "Bd-h|J
this.indexes = indexes; ?C|'GkT
} N:`_Vl
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publicint getStartIndex(){ ^/n1hg
return startIndex; -P;3BHS$T
} }U}zS@kI
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publicvoid setStartIndex(int startIndex){ Rw+r1vW:A
if(totalCount <= 0) )tlj{ 7p
this.startIndex = 0; [2@:jLth=
elseif(startIndex >= totalCount) N9-0b
this.startIndex = indexes rJiF2 W
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[indexes.length - 1]; E@ea?Sx
elseif(startIndex < 0) #2]*qgA4
this.startIndex = 0; A/y|pg5
else{ S{^x]h|?
this.startIndex = indexes bxE~tsM"@Y
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[startIndex / pageSize]; aO{@.
} j2G^sj"|
} ]]|#+$ ~
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publicint getNextIndex(){ P'KA-4!
int nextIndex = getStartIndex() + h8/tKyr8(
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pageSize; ag'hHFV
if(nextIndex >= totalCount) AXbb-GK
return getStartIndex(); tddwnpnSw
else Z_GGH2u
return nextIndex; ]xRR/S4
} i!YfR]"}
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publicint getPreviousIndex(){ \GEz.Vb
int previousIndex = getStartIndex() - :!Ci#[g
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pageSize; xP\s^]e
if(previousIndex < 0) Bz'.7"
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return0; 0moA mfc
else l%+ &V^:
return previousIndex; k|OM?\
} SPqJ
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} NfDS6i.Fqp
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抽象业务类 7rD 8
java代码: #M!u';bZ
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/** /Xi21W/
* Created on 2005-7-12 0(i3RPIj\
*/ _i>_S n1"
package com.javaeye.common.business; dNR/|
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import java.io.Serializable; nc1~5eo
import java.util.List; <VZ43I
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import org.hibernate.Criteria; n[>hJ6
import org.hibernate.HibernateException; zU1D@
import org.hibernate.Session; b@J "b(
import org.hibernate.criterion.DetachedCriteria; ((gI OTV
import org.hibernate.criterion.Projections; k
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import )2c]Z|
*Xnf}Ozx
org.springframework.orm.hibernate3.HibernateCallback; ?=lb@U
import U-DQ?OtmC@
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org.springframework.orm.hibernate3.support.HibernateDaoS =cRmaD
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upport; d5-Q}D,P
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import com.javaeye.common.util.PaginationSupport; ?Tc|3U
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public abstract class AbstractManager extends ~AD>@;8fG
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HibernateDaoSupport { RF*>U a
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privateboolean cacheQueries = false; TeuZVy8a
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privateString queryCacheRegion; dWzf C@]
@~vg=(ic(
publicvoid setCacheQueries(boolean R:n|1]*f3X
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cacheQueries){ MP}-7UA#K
this.cacheQueries = cacheQueries; P,ZQ*Ju
} oaha5aWH
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publicvoid setQueryCacheRegion(String x
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queryCacheRegion){ DI)"FOM6
this.queryCacheRegion = 3B;Gm<fJ9N
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queryCacheRegion; <Z t ]V`-
} bq5ySy{8
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publicvoid save(finalObject entity){ L[PqEN\i
getHibernateTemplate().save(entity); )'jGf;du
} M#Z^8(
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publicvoid persist(finalObject entity){ H.M:
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getHibernateTemplate().save(entity); `yq)
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} pS-o*!\C.
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publicvoid update(finalObject entity){ n<|8Onw
getHibernateTemplate().update(entity); gna!Q
} q=e;P;u
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publicvoid delete(finalObject entity){ V|A.M-XLv4
getHibernateTemplate().delete(entity); c61 1&
} +Y*4/w[
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publicObject load(finalClass entity, b&A/S$*
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finalSerializable id){ }+lK'6
return getHibernateTemplate().load \_u{ EB'b
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(entity, id); B t3++ Mj
} k6DJ(.n'%a
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publicObject get(finalClass entity, +z9BWo!{I
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finalSerializable id){ i.^UkN{
return getHibernateTemplate().get wY8Vc"
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(entity, id); _[8JSw7
} >9XG+f66E
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publicList findAll(finalClass entity){ _s-X5xU
return getHibernateTemplate().find("from Y,mo}X<>
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" + entity.getName()); p\I3 fI0i
} 6`7`herE}
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publicList findByNamedQuery(finalString ?mV2|;
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namedQuery){ 9*JxP%8T~X
return getHibernateTemplate 5Th\wTh04
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().findByNamedQuery(namedQuery);
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} .rg "(I
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publicList findByNamedQuery(finalString query, gzK/ l:
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finalObject parameter){ .@r{Tq,%q8
return getHibernateTemplate VwBw!,%Ab
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().findByNamedQuery(query, parameter); [$$R>ELYQ
} ;E{@)X..|
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publicList findByNamedQuery(finalString query, U4a8z<l$
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finalObject[] parameters){ L#D)[v"
return getHibernateTemplate =.J>'9 Q
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().findByNamedQuery(query, parameters); |VE.khq#
} \p\p~FVS
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publicList find(finalString query){ e?XGv0^qu
return getHibernateTemplate().find 7"eIZ
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(query); -hF!_);{
} oQVm)Bn'R
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publicList find(finalString query, finalObject we}5'bS>
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parameter){ pi;fu
return getHibernateTemplate().find 4ke.p<dG
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(query, parameter); $Y$s*h_-/<
} nJgN2Z
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public PaginationSupport findPageByCriteria Pr1OQbg]8
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(final DetachedCriteria detachedCriteria){ M_?B*QZJI
return findPageByCriteria blG?("0!
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); :[PA .Upi
} hOqNZ66{
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public PaginationSupport findPageByCriteria v-F|#4Q=ut
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(final DetachedCriteria detachedCriteria, finalint SoCN.J30
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startIndex){ RT%{M1tkS
return findPageByCriteria J1r\Cp+h0
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(detachedCriteria, PaginationSupport.PAGESIZE, h^."wv
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startIndex); E9.1~
)
} 2:[<E2z
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public PaginationSupport findPageByCriteria kDiR2K&
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(final DetachedCriteria detachedCriteria, finalint k9y/.Mu
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pageSize, )>rYp
)
finalint startIndex){ W"~"R
return(PaginationSupport) H]dN'c-
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getHibernateTemplate().execute(new HibernateCallback(){ 'o8,XBv-
publicObject doInHibernate hR>`I0|p&
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(Session session)throws HibernateException { Y}\3PaUa
Criteria criteria = 527u d^:
*MWI`=c
detachedCriteria.getExecutableCriteria(session); {Z$]Rj
int totalCount = Tz(Dhb,
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((Integer) criteria.setProjection(Projections.rowCount >^f]Lgp
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()).uniqueResult()).intValue(); 85H*Xm?d#
criteria.setProjection !$-QWKD4
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(null); C0>)WVCK
List items = 5tVg++I
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criteria.setFirstResult(startIndex).setMaxResults Yk7^?W
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(pageSize).list(); } f!wQxb
PaginationSupport ps = Kna@K$6{w=
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new PaginationSupport(items, totalCount, pageSize, .KYDYdoS'
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startIndex);
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return ps; SwH #=hg
} ka8=`cn
}, true); >BMtR0
} !uKuO
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public List findAllByCriteria(final w (,x{Bg\
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DetachedCriteria detachedCriteria){ ^X*l&R_=R
return(List) getHibernateTemplate p!(]`N
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().execute(new HibernateCallback(){ Kku@!lv
publicObject doInHibernate wD<W'K
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(Session session)throws HibernateException { oFu( J
Criteria criteria = ub{Yg5{3S\
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detachedCriteria.getExecutableCriteria(session); fqm6Pd{:(
return criteria.list(); `7
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} I"jub
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}, true); WODgG@w
} ~HX'8\5
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public int getCountByCriteria(final ;uU 8$
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DetachedCriteria detachedCriteria){ %B# 8
Integer count = (Integer) <*4r6UFR
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getHibernateTemplate().execute(new HibernateCallback(){ @%As>X<3t
publicObject doInHibernate 'p,54<e
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(Session session)throws HibernateException { sGJZG
Criteria criteria = )9rJ]D^B
DM !B@
detachedCriteria.getExecutableCriteria(session);
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return A@ G%*\UZ
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criteria.setProjection(Projections.rowCount VSm{]Z!x
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()).uniqueResult(); 14Jkr)N
} n\4sNoFI
}, true); xNxSgvco,
return count.intValue(); Z
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} KQrG|<J
} !*-|s}e
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用户在web层构造查询条件detachedCriteria,和可选的 EYKV}`
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 K!SFS
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PaginationSupport的实例ps。 NB)22 %
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ps.getItems()得到已分页好的结果集 ,S=ur%
ps.getIndexes()得到分页索引的数组 Md1ePp]
ps.getTotalCount()得到总结果数 a"X9cU[
ps.getStartIndex()当前分页索引 BP0*`TY
ps.getNextIndex()下一页索引 8}!WJ2[R
ps.getPreviousIndex()上一页索引 'di(5
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 a.s5>:Ct
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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 .d%CD`8!
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一下代码重构了。 rW0-XLbL5H
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我把原本我的做法也提供出来供大家讨论吧: : ]~G9]R`
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首先,为了实现分页查询,我封装了一个Page类: ^1,VvLA+
java代码: HO9w"){d$
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/*Created on 2005-4-14*/ 3g5
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package org.flyware.util.page; /X97dF)zt
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/** QNgfvy
* @author Joa 4Yya+[RY
* 8~8VoU&
*/ #\$AB_[ot>
publicclass Page { y^hCO:`l3
p`06%"#
/** imply if the page has previous page */ Lk1e{!a
privateboolean hasPrePage; AqucP@
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/** imply if the page has next page */ ,ftKRq
privateboolean hasNextPage; #hF(`oX}4K
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/** the number of every page */ jS| 9jg:
privateint everyPage; %*Lv
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/** the total page number */ 58o'Q
privateint totalPage;
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/** the number of current page */ )V?:qCuY>
privateint currentPage; N)^`
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/** the begin index of the records by the current 6k*,Yei
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query */ g.T:72"
privateint beginIndex; swLrp
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/** The default constructor */ \*5${[
public Page(){ 8t
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} :pvJpu$]
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/** construct the page by everyPage aV`_@F-8
* @param everyPage 5v,_ Hgh
* */ R-J^%4U`7
public Page(int everyPage){ 6>&h9@
this.everyPage = everyPage; |!E: [UH
} JBt2R=
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/** The whole constructor */ fuF!3Q
public Page(boolean hasPrePage, boolean hasNextPage, 3
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int everyPage, int totalPage, P:&X1MC
int currentPage, int beginIndex){ = 4 wf
this.hasPrePage = hasPrePage; ZfP$6%;_
this.hasNextPage = hasNextPage; G_/DzJBF
this.everyPage = everyPage; z^^)n
this.totalPage = totalPage; N|\Q:<!2_w
this.currentPage = currentPage; T1#r>3c\
this.beginIndex = beginIndex; NWS3-iZ|8
} < wi9
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/** t4v@d
* @return @jY=b<
* Returns the beginIndex. h'ik19
*/ v8f1o$R
publicint getBeginIndex(){ _=-B%m
return beginIndex; Cd2A&RB
} -+{<a!Nb
U'k 0;
/** fs\A(]`$
* @param beginIndex M`)/^S9
* The beginIndex to set. a]nK!;>$
*/ 1Y'NG<d_
publicvoid setBeginIndex(int beginIndex){ '8w>=9Xl
this.beginIndex = beginIndex; a&RH_L jM
} )9i$ 1"a(
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/** |ya.c\}q
* @return ohna1a^
* Returns the currentPage. W`v$-o-
*/ @8*lqV2
publicint getCurrentPage(){ #+#^cqjZ
return currentPage; AF\Jh+ynT!
} 0TWd.+
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/** gy>B
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* @param currentPage 5.d[C/pRw
* The currentPage to set. sOVU>tb\'
*/ L Q0e@5
publicvoid setCurrentPage(int currentPage){ L Iz<fB
this.currentPage = currentPage; 7>lM^ :A
} C?j:+
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/** gVNoC-n)
* @return F.),|t$\
* Returns the everyPage. KX
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*/ 2F
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publicint getEveryPage(){ gCq'#G\Z
return everyPage; T>68 ,; p
} Qk72ra)
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/** C),i#v
* @param everyPage Z+=M_{`{
* The everyPage to set. 1Li*n6tLX`
*/ R*/s#*gmL
publicvoid setEveryPage(int everyPage){ F3[,6%4v
this.everyPage = everyPage; Q[{RNab
} 5]xSK'6W
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/** wJj:hA}
* @return p(6 sN=
* Returns the hasNextPage. P ; h8
*/ ALj~e#{;z
publicboolean getHasNextPage(){ &`oybm-p(
return hasNextPage; TV=K3F5)M
} McpQ7\*h
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/** 5th?m>
* @param hasNextPage [ ou$*
* The hasNextPage to set. y @S_CB47
*/ iX[g
publicvoid setHasNextPage(boolean hasNextPage){ MU%7'J :_
this.hasNextPage = hasNextPage; v7n@CWnN
} F1A40h7R$Y
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/** $<yhEvv
* @return .5uqc.i"f
* Returns the hasPrePage. =*1NVi $n
*/ e3ce?gk
publicboolean getHasPrePage(){ Lw2VdFi>E&
return hasPrePage; |]?zH~L
} &r\8VEZq"
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/** .cbC2t95
* @param hasPrePage YS_3Cq
* The hasPrePage to set. C]p@7"l
*/ Q8MIpa!:
publicvoid setHasPrePage(boolean hasPrePage){ 7Ja*T@ ! h
this.hasPrePage = hasPrePage; ;tSAQ
} j+@3.^vK
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/** ]IE Z?+F,
* @return Returns the totalPage. L$BV`JWPw
* "Kdn`zN{
*/ G;$;$gM
publicint getTotalPage(){ 'qvj[lpGr
return totalPage; K|YB)y
} mf)+ 5On
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/** f:-l}Zj
* @param totalPage Zskj?+1
* The totalPage to set. U8AH,?]#
*/ QeG9CS)E}j
publicvoid setTotalPage(int totalPage){ |?ssHW
this.totalPage = totalPage; HC/z3b;
} e"52'zAV-
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} r4fHD~#l{
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p |1u,N
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#
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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 [ r8 ZAS
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个PageUtil,负责对Page对象进行构造: B+snHabS6
java代码: !TJ,:c]4{!
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/*Created on 2005-4-14*/ c#sHnpP
package org.flyware.util.page; r]UF<*$
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import org.apache.commons.logging.Log; 4uo`XJuQ
import org.apache.commons.logging.LogFactory; [104;g <
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/** m^G(qoZ]
* @author Joa P0jr>j@^-
* lU%}_!tp3/
*/ L]|mWyzT
publicclass PageUtil { 7P7OTN
EP 4]#]5
privatestaticfinal Log logger = LogFactory.getLog `om+p?j
{PcJuRTHB
(PageUtil.class); U~N7\Pa4
<"J]u@|
/** dy&UF,l6
* Use the origin page to create a new page 7l=;I %
* @param page w{6C4~0
* @param totalRecords Wc[,kc
* @return a/,>fv9;$
*/ w8UuwFG?<
publicstatic Page createPage(Page page, int r8Mx+r
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totalRecords){ .mt%8GM
return createPage(page.getEveryPage(), |zYOCDFf
o)/Pr7Qn
page.getCurrentPage(), totalRecords); {O^u^a\m
} !qj[$x-ns
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/** La;G S
* the basic page utils not including exception Aw |;C
}OL"38P
handler l9I r@.m
* @param everyPage @#)` -]g
* @param currentPage "y,YC M`
* @param totalRecords Xq*^6*E-}
* @return page o@Oz
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*/ ^Tm`motzh
publicstatic Page createPage(int everyPage, int *h!fqT%9
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currentPage, int totalRecords){ /|1p7{km
everyPage = getEveryPage(everyPage); #]kjyT0
currentPage = getCurrentPage(currentPage); ttzNv>L,
int beginIndex = getBeginIndex(everyPage, 6<._^hyq
"6$V1B0KW
currentPage); MC}t8L=
int totalPage = getTotalPage(everyPage, 2Wz8E2.
<U@N^#
totalRecords); 4Z( #;9f
boolean hasNextPage = hasNextPage(currentPage, ^dHQ<L3.*
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totalPage); i2~uhGJ
boolean hasPrePage = hasPrePage(currentPage); <Kd(fFe
Q +^&
returnnew Page(hasPrePage, hasNextPage, -n|bi cP
everyPage, totalPage, 1cLtTE
currentPage, d(T4Kd$r
CubQ6@,
beginIndex); .$qa?$@
} G<;~nAo?f0
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privatestaticint getEveryPage(int everyPage){ <v:VA!]
return everyPage == 0 ? 10 : everyPage; 5ilGWkb`'X
} N+|NI?R?}
GM%+yS}(P
privatestaticint getCurrentPage(int currentPage){ n|w+08c"
return currentPage == 0 ? 1 : currentPage; 1F^Q* t{
} 9-KhJq%
}}AIpYp,P
privatestaticint getBeginIndex(int everyPage, int ^Xk!wJ
I&;>(@K
currentPage){ .f\LzZ-I:
return(currentPage - 1) * everyPage; .Pc>1#z&[
} 21uK&nVf^l
~s!Q0G^G
privatestaticint getTotalPage(int everyPage, int a1U|eLmUb
M"~jNe|
totalRecords){ ;b$P*dSG}
int totalPage = 0; Dqx#i-L23
_ E;T"SC
if(totalRecords % everyPage == 0) Zv u6/#
totalPage = totalRecords / everyPage; Z/#_Swv
else w,LtQhQ
totalPage = totalRecords / everyPage + 1 ; CLR1CGnn7
8i#
return totalPage; Rh!UbEPjC
} 06&J!,p
:
(vs<Fo|]
privatestaticboolean hasPrePage(int currentPage){ *'<AwG&
return currentPage == 1 ? false : true; M!UTqf7XL
} 2Je$SE8
.DCHc,DxA
privatestaticboolean hasNextPage(int currentPage, 0#,a#P
8Bf>
int totalPage){ 3Vb4zZsl
return currentPage == totalPage || totalPage == > H!sD\b
6>>; fy2
0 ? false : true; Kc/1LeAik
} rhJ&* 0M
e~o!Qm
_gvFs%J
} ;[v!#+yml
R'Sd'pSDN
_C?j\Wy
CdolZW-!"
SepjF
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 {%V(Dd[B6
{i5?R,a)
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 DBT4 W/
"g{q=[U}
做法如下: m|a9T#B(
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 :RaQ
=C
C"{^wy{sL
的信息,和一个结果集List: (o^tmH*
java代码: "HMEoZ
{keZ_2
"[ bkdL<
/*Created on 2005-6-13*/ L$ZjMJ
package com.adt.bo; d>NGCe
7FB?t<x
import java.util.List; i]JTKL{\q
8:ubtB
import org.flyware.util.page.Page; Kb.qv)6i*
D!<F^mtl
/** gD,&TW
* @author Joa ?YhDjQs
*/ L.Y3/H_
publicclass Result { 8Sbz)X
,UNb#=it
private Page page; ZoW1Cc&p
z+"tAVB[i
private List content; uZqL'l+/y
B=_w9iVN
/** t*{L[c9.Uq
* The default constructor ,+=9Rp`md
*/ }V?m
=y [
public Result(){ ]z'&oz
super(); y7Po$ )8l
} F'bwXb**
}K {1Bm@S
/** iHa?b2=)
* The constructor using fields _jWs(OmJ
* E$d#4x
* @param page 5E!C?dv(z
* @param content OgQdyU
*/ ]?9*Vr:P^
public Result(Page page, List content){ nL@'??I1
this.page = page; mypV[
this.content = content; BI'>\hX/V
} Ayz*2N`%
> I2rj2M#
/** S|85g1}t
* @return Returns the content. *t@A-Sn
*/ 87 Z[0>
publicList getContent(){ #mxOwvJ
return content; !Sc"V.o@!
} CSM"Kz`
AIF?>wgq
/** 6g(;2gY
* @return Returns the page. bLqy7S9x
*/ agIqca;
public Page getPage(){ DUp`zW;B
return page; I!x.bp~V!
} KX)n+{
2d)Dhxzxk
/** L%'J]HL-
* @param content ?
SFBUX(p
* The content to set. !fh (k
*/ _N DQ2O
public void setContent(List content){ uP~,]ci7
this.content = content; ^T=9j.e'ja
} B8&q$QV
q_M N
/** l;?:}\sI=
* @param page pUIN`ya[[
* The page to set. Q(|@&83].
*/ X+X:nL.t
publicvoid setPage(Page page){ yD\q4G
this.page = page; 1w,_D.1'
} c<lp<{;
} RS5<] dy
f:o.[4p2
~_ THvx1
"LBMpgpU
0~|0D#klB
2. 编写业务逻辑接口,并实现它(UserManager, aLk3Yg@X
b<h((]Q>^
UserManagerImpl) 4:/]Y=)x
java代码: 0'^M}&zCi
Y}~sTuWU
>xWS>
/*Created on 2005-7-15*/ -@v^. @[Z&
package com.adt.service; 7B?Y.B
Lg:1zC
import net.sf.hibernate.HibernateException; Wu>]R'C
@0 +\:F
import org.flyware.util.page.Page; 26V6Y2X
T(!1\ TB
import com.adt.bo.Result; *zrT;jG
m&)/>'W
/** Dri6\/0
* @author Joa u[a-9^&g
*/ Nr|Gw
@+
publicinterface UserManager { eI8o#4nT
* #yF`_p
public Result listUser(Page page)throws hf`y_H+\7
WowKq0sn
HibernateException; `M@ESA(e
p=+Y7NE)
} xP8/1wd.
0h-NT\m
gtKih
O,$*`RZpx
fB2ILRc
java代码: ak 7%
" ityx?
l\_!oa~
/*Created on 2005-7-15*/ ?1Nz
,Lc$
package com.adt.service.impl; B`SX3,3
<spG]Xa<
import java.util.List; x[A|@\Z
757&bH|a
import net.sf.hibernate.HibernateException; l)r\SE1
.Xlo-gHk
import org.flyware.util.page.Page; Agd"m4!
import org.flyware.util.page.PageUtil; <bcf"0A
#X(2
import com.adt.bo.Result; 1P)K@j
import com.adt.dao.UserDAO; pH~\~
import com.adt.exception.ObjectNotFoundException; 4LSs WO<@
import com.adt.service.UserManager; | W@ ~mrO
g;l K34{
/** kNuvJ/St
* @author Joa ^-%'ItVO
*/ 8\J$\Edv
publicclass UserManagerImpl implements UserManager { l;-2hZ
:3F[!y3b
private UserDAO userDAO; yY]x''K
&dB@n15'A
/** xM())Z|2
* @param userDAO The userDAO to set. "rdpA[>L
*/ f]*;O+8$LN
publicvoid setUserDAO(UserDAO userDAO){ enk`I$Xx
this.userDAO = userDAO; ch#)XomN
} 3MQHoxX
WUS%4LL(
/* (non-Javadoc) yLRe'5#m
* @see com.adt.service.UserManager#listUser 0>[]Da}
T
m"B
(org.flyware.util.page.Page) |AvPg
*/ .7.G}z1
public Result listUser(Page page)throws 0hY3vBQ!
yp~z-aRa
HibernateException, ObjectNotFoundException { ~n -N
int totalRecords = userDAO.getUserCount(); '`8 ^P
if(totalRecords == 0) o0Teect=
throw new ObjectNotFoundException ru:"c^W:[
G[}v?RLI
("userNotExist"); u<j;+-]8h
page = PageUtil.createPage(page, totalRecords); 8P]nO+
List users = userDAO.getUserByPage(page); ^*jwe^
returnnew Result(page, users); $H*8H`
} u?V}pYX
@@ j\OR
} 1_7p`Gxt[/
2K4Xu9-i:b
<v1H1'gv
Boj R"
[C!*7h
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 "Lvk?k
)hx
E}Cz(5
询,接下来编写UserDAO的代码: [l=@b4Og
3. UserDAO 和 UserDAOImpl: ,RV>F_
java代码: nLL2/!'n
Q7amp:JFb
i59}6u_f
/*Created on 2005-7-15*/ -|x7<$Hw
package com.adt.dao; -.Wwo(4
drpx"d[c
import java.util.List; G!%m~+",
n)N!6u
import org.flyware.util.page.Page; x~k3kj
ESviWCh0Fl
import net.sf.hibernate.HibernateException; 2fdN@iruB
9q ]f]S.L
/** `*[Kmb\
* @author Joa PY|zN|
*/ ZQ"dAR/y
publicinterface UserDAO extends BaseDAO { I484cR2.
5VE=Oo#&
publicList getUserByName(String name)throws .BjWZj
FM%WMyb[
HibernateException; UhR^Y{W5
"IS; o o$g
publicint getUserCount()throws HibernateException; sudh=_+>
&$ }6:
publicList getUserByPage(Page page)throws MoxWnJy}
dkC_Sh{
HibernateException; #0)TS
[`|t( E'
} /#5rt&q
I!b"Rv=Nf-
hxdjmc-
kM-8%a2i
vEjf|-Mb9
java代码: R;,5LS&*a
shGUG;
_I)TO_L;
/*Created on 2005-7-15*/ uv5NqL&
package com.adt.dao.impl; q'fOlq
^G qO>1U
import java.util.List; xqdkc^b
?Kmz urG
import org.flyware.util.page.Page; 'RwfW|~6
Vuy%7H
import net.sf.hibernate.HibernateException; TlO=dLR7d
import net.sf.hibernate.Query; LQqba4$
irh Z
import com.adt.dao.UserDAO; 2K3j3 |T
nUs=PD3)
/**
6x5Q*^w
* @author Joa -7oIphJ=\
*/ Z9H2! Cp
public class UserDAOImpl extends BaseDAOHibernateImpl ^0"fPG`
GRpwEfG
implements UserDAO { S^q^=q0F
m
Urb
/* (non-Javadoc) "cS7E5-|
* @see com.adt.dao.UserDAO#getUserByName 0^L:`[W+
~Y0K Wx4
(java.lang.String) ;"f9"
*/ &'neOf/~
publicList getUserByName(String name)throws f*V^HfiQb
p%Q{Rqc)
HibernateException { e`B!)Sr
String querySentence = "FROM user in class J*ofa>
lX.1B&T9Lr
com.adt.po.User WHERE user.name=:name"; 0(C[][a*u
Query query = getSession().createQuery (g dzgLHy
3 p -SpUvp
(querySentence); I+Y Z+
query.setParameter("name", name); RYl{89
return query.list(); 6wOj,}2Mn
} ui"`c%2n
@Nm{H
/* (non-Javadoc) gjiS+N[
* @see com.adt.dao.UserDAO#getUserCount() LvGo$f/9
*/ "tb KbFn9
publicint getUserCount()throws HibernateException { K7$Q.
int count = 0; p]e.E`'S
String querySentence = "SELECT count(*) FROM hey/#GC*
xhCNiYJ|
user in class com.adt.po.User"; /2r&ga&
Query query = getSession().createQuery )MV `'i
79Aa~ +i'_
(querySentence); `&)
count = ((Integer)query.iterate().next 7lOAu]Zx
1)e[F#|
()).intValue(); b;`MHEzw&q
return count; '[[IalQ?
} NUBzc'qb
zzC{I@b
/* (non-Javadoc) e*<pO@Uy
* @see com.adt.dao.UserDAO#getUserByPage nbw8YO(=
rIyIZWkI
(org.flyware.util.page.Page) `^g-2~
*/ |+-b#Sa9
publicList getUserByPage(Page page)throws Nog{w
JBV
06T_4o
HibernateException { G]-\$>5R
String querySentence = "FROM user in class mmC MsBfL
X#W6;?Z\
com.adt.po.User"; B|>eKI
Query query = getSession().createQuery uYE"OUNWL
QVb{+`.7
(querySentence); ju.`c->k"
query.setFirstResult(page.getBeginIndex()) x {Rj2~KC
.setMaxResults(page.getEveryPage()); g|]Hm*
return query.list(); pB VzmQF
} ASS<XNP
80U(q/H%9
} )Zvn{
$?&distJ
!(_qM
r-hb]!t
nS!m1&DeD
至此,一个完整的分页程序完成。前台的只需要调用 3cH^
,F
5uM`4xkj
userManager.listUser(page)即可得到一个Page对象和结果集对象 vQ5rhRG)E
e{Mkwi+j
的综合体,而传入的参数page对象则可以由前台传入,如果用 5 yL"=3&+
[7{cf`C
webwork,甚至可以直接在配置文件中指定。 !4"$O@U4
efyGjfoO
下面给出一个webwork调用示例: V' sq'XB
java代码: M\08 7k
w\JTMS$
&61h*s
/*Created on 2005-6-17*/ -9 |)O:
package com.adt.action.user; 4?`*#DPl
@Y%i`}T%(
import java.util.List; ;A?86o'?
}o=s"0 a
import org.apache.commons.logging.Log; 3|Y.+W
import org.apache.commons.logging.LogFactory; ;%/}(&E2
import org.flyware.util.page.Page; ;0dl
Jk`0yJi$q
import com.adt.bo.Result; $B )jSxSy
import com.adt.service.UserService; GSGaYq
import com.opensymphony.xwork.Action; tv9 R$-cJ
6(B[(Af
/** >Qf`xUZ
* @author Joa #%/0a
*/ <@c9S,@t
publicclass ListUser implementsAction{ Jb!s#g
@i>4k
privatestaticfinal Log logger = LogFactory.getLog K pKZiUQm
ZyrVv\'
(ListUser.class); ]%(X}]}
_10I0Z0
private UserService userService; |Mnc0Fgvy,
w!l*!G
private Page page; %G,d&%f
0[-@<w ^j
privateList users; `9DW}
p+F>+OQ*
/* DPWnvd
* (non-Javadoc) )5<c8lzp
* IP#qT
`=}
* @see com.opensymphony.xwork.Action#execute() <[z9*Tm
*/ &A&2z l %#
publicString execute()throwsException{ gGbJk&E
Result result = userService.listUser(page); pq,8z= Uf
page = result.getPage(); #@cEJV;5"
users = result.getContent(); zE=^}K+
return SUCCESS; h(FFG%H(
} *5" )3\/
j-/F*P
/** YZc{\~d
* @return Returns the page. 1{CVd m<9
*/ nhB.>ReAi
public Page getPage(){ P\2x9T
return page; N}\3UHtO
} $*+`;PG-
?fvK<0S`
/** M^y5 Dep
* @return Returns the users. 6M6r&,yRu
*/ \x~},!l
publicList getUsers(){ T:VFyby\w
return users; _sqV@ J
} $_u)~O4$
kXZG<?
/** $G#)D^-5G
* @param page +Y440Tz
* The page to set. DP
&*P/
*/ ~ll+/w\4
publicvoid setPage(Page page){ ByW,YKMy
this.page = page; 4u]>$?X1_
} %H7H0%qW
]]V|]}<)m
/** aq]bF%7
* @param users ,M9Hdm
* The users to set. Y'x+!&H
*/ g:[yA{Eh
publicvoid setUsers(List users){ T3/Gl6f
this.users = users; 0t0m?rVW
} l\t<_p/I)^
dQPW9~g8Hg
/** HAGpM\Qa
* @param userService 6$\'dkufQ
* The userService to set. w*IDL0#
*/ X[$FjKZh=F
publicvoid setUserService(UserService userService){ L[}Ak1 A
this.userService = userService; f>ilk Q`
} 9Z. WR-}
} {GQRJ8m
*l8:%t\
t|cTl/i
4
_iZ9Ch\
%8! }" Xa
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, ~d&W;mef-
]t.6bb4
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 8i?:aN[.1b
Kd').w
么只需要: J+f*D+x1
java代码: G>j4b}e
DBZ^n9
P(~vqo>!
<?xml version="1.0"?> W4S! rU
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork zr1A4%S"
E9v_6d[
1.0//EN" "http://www.opensymphony.com/xwork/xwork- F@kd[>/[
s92SN F}g
1.0.dtd"> 0tp3mYd
+jGSD@32>
<xwork> bv4G!21]*;
%j2ZQ/z
<package name="user" extends="webwork- uxD$dd?
.a]9 rQQ&_
interceptors"> 6,Y<1b*|Vo
VgcLG ]tE[
<!-- The default interceptor stack name <P1x3
{|/y/xYgy'
--> "'*w_H0
<default-interceptor-ref Ggp. %kS6F
q;=! =aRg
name="myDefaultWebStack"/> ]Qh0+!SdG
^mCKRWOP'
<action name="listUser" \LQ54^eB
Q*8=^[x
class="com.adt.action.user.ListUser"> }(Dt,F`
<param TAKvE=a;
hScC<=W
name="page.everyPage">10</param> .{
r
%C4q9
<result _Xzl=j9[
*MZa|Xy
name="success">/user/user_list.jsp</result> oTLpq:9J
</action> y-#01Z
f,'9Bj.~
</package> 1_6oM/?'
[mA\,ny9
</xwork> y#)ad\
-5sKJt]+i
.%T.sQ
p1B~F
2 s<uT
Mib<1ZM
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 {~+o+LV
C`r{B.t`GT
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。 >`=<(8bu
oeIza<:=R
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 o=y0=,:a?9
< r7s,][&
o-r00H|
Z@QJ5F1y
;FO( mL (
我写的一个用于分页的类,用了泛型了,hoho H&E3RU>`
^% jk. *
java代码: YK6zN>M}E
XX[CTh?O%
7dtkylW
package com.intokr.util; X>4qL'b:z
hmM2c15T5
import java.util.List; :~%{
m9 D'yXZ
/** b,):&M~p
* 用于分页的类<br> IJ#+"(?7,u
* 可以用于传递查询的结果也可以用于传送查询的参数<br> Auk#pO#
* (hFyp}jkk
* @version 0.01 $hq'9}ASOL
* @author cheng 5><KTya?=
*/ l/g6Tv`w
public class Paginator<E> { .}ePm(
privateint count = 0; // 总记录数 d}--}&r
privateint p = 1; // 页编号 Z,}c)
privateint num = 20; // 每页的记录数 [
F7ru4"{
privateList<E> results = null; // 结果 s?~lMm' !
]x:>!y
/** 3T84f[CFJ
* 结果总数 br4?_,
*/ 1XPYI
publicint getCount(){ ~1.B
fOR8
return count; \_8.\o"@*#
} 9U]j@*QN
c@Q&i
publicvoid setCount(int count){ O#72h]
this.count = count; A8U\/GP
} s>c0K@ADO
1yV+~)by3
/** pUD(5v*0R
* 本结果所在的页码,从1开始 f S-PM3
* iM(Q-%HP_
* @return Returns the pageNo. TAp8x
*/ ]mT2a8`c.r
publicint getP(){ \_l4li
return p; Q7 @oAeNd
} fF]w[lLDv
/lDei}
/** @M&qH[tK-A
* if(p<=0) p=1 N977F$Bo
* "xV0$%
* @param p Y4Y~ep
*/ Nn='9s9F?}
publicvoid setP(int p){ S?<hs,
if(p <= 0) fOJTy0jX8
p = 1; #bwGDF
this.p = p; #$ooV1E
} gnN"6r1
rBUWzpE"
/** z=yE- I{
* 每页记录数量 O
8XHaVLg3
*/ *~0U4kw+
publicint getNum(){ 7Xf52\7n
return num; @RXkj-,eC#
} b!oj3|9
9|NH5A"H.
/** EFn[[<&><t
* if(num<1) num=1 bZW dd6
*/ |qz&d=>
publicvoid setNum(int num){ {@ Z=b5/P
if(num < 1) oe<DP7e
num = 1; a4\j.(w)$D
this.num = num; X+kgx!u'y
} 2Og<e|
,#U[)}im
/** DPr~DO`b
* 获得总页数 RmRPR<vGW
*/ $0XR<D
publicint getPageNum(){ wDDNB1_E
return(count - 1) / num + 1; m^gxEPJK
} #7['M;_
`!Yd$=*c_&
/** #\Zr$?t|V
* 获得本页的开始编号,为 (p-1)*num+1 eI,H
*/ 2{<o1x,Ym
publicint getStart(){ \![ p-mW{
return(p - 1) * num + 1; Q?>DbT6
} DR7 JEE
?azcWf z0
/**
3 #"!Hg
* @return Returns the results. >!Dp'6
*/ q~`dxq`}
publicList<E> getResults(){ <b:xyHS
return results; bs0[ a 1/
} F-Bj
V5' (op /
public void setResults(List<E> results){ mgMa)yc!dp
this.results = results; otX/sg.B*
} |u]IOw&1
xVk5%
public String toString(){ Ey=ymf.}
StringBuilder buff = new StringBuilder qe'RvBz
7n,=`0{r
(); Y_)xytJ$
buff.append("{"); +U)4V}S)
buff.append("count:").append(count); q_cP<2`@V
buff.append(",p:").append(p); 1my1m
buff.append(",nump:").append(num); 8SA"
bH:
buff.append(",results:").append +o?;7
n8tw8o%&[
(results); 9yz@hdG
buff.append("}"); %n6NVi_[
return buff.toString(); /@B2-.w
} WK0:3q(P
!
(Q[[M
} $0k7W?tu
lffw
"
X;n09 L`CB