Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 W4| ;JmT.r
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 FQ 4rA 4
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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'^{B
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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 P~*fZ)\}F@
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分页支持类: >]`x~cE.5
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java代码:
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package com.javaeye.common.util; R3<+z
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import java.util.List; 5-J-Tn
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publicclass PaginationSupport { -Z@p
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publicfinalstaticint PAGESIZE = 30; yqU++;6
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privateint pageSize = PAGESIZE; h
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privateList items; GB=q}@&8p
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privateint totalCount; eOb`uyi
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privateint[] indexes = newint[0]; |bk*Lgkzw
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privateint startIndex = 0; W< n`[
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public PaginationSupport(List items, int aI<~+ ]
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totalCount){ QJ>>&`{,
setPageSize(PAGESIZE); a:fHTU=\p
setTotalCount(totalCount); 2
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setItems(items); :QVGY^c
setStartIndex(0); Y!L jy
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} ?Z=v&d[o)
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public PaginationSupport(List items, int qEAF!iB]L
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totalCount, int startIndex){
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setPageSize(PAGESIZE); c;^ J!e
setTotalCount(totalCount); ^Toi_
setItems(items); R+K[/AA
setStartIndex(startIndex); #RF=a7&F
} Trrh`@R
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public PaginationSupport(List items, int @I&"P:E0F;
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totalCount, int pageSize, int startIndex){ `T70FsSJ
setPageSize(pageSize); Q-F9oZ*0
setTotalCount(totalCount); "7HB3?2>W
setItems(items); "" U_|JH-
setStartIndex(startIndex); {9Y'v
} `9ox?|iJ
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publicList getItems(){ #*!$!c{
return items; OLrD4 e
} aM~fRra7
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publicvoid setItems(List items){ L3AwL)I
this.items = items; zqh{=&Tjx
} Db=gS=Qm
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publicint getPageSize(){ V5B-S.i@
return pageSize; {Fi@|'
} :j~5(K"
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publicvoid setPageSize(int pageSize){ O[!o1.
this.pageSize = pageSize; %U
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} >v[(w1?rX
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publicint getTotalCount(){ {n]sRz
return totalCount; H#inr^Xa
} E: GJ$I
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publicvoid setTotalCount(int totalCount){ .jp]S4~
if(totalCount > 0){ \#aVu^`eX
this.totalCount = totalCount; ?^~"x.<nr
int count = totalCount / yUO|3ONT
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pageSize; PoJ$%_a}
if(totalCount % pageSize > 0) $hSZ@w|IF
count++; :,m)D775S
indexes = newint[count]; BuTIJb+Q\
for(int i = 0; i < count; i++){ H|UL5<:]D
indexes = pageSize * %z~U@Mka
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i; :eW~nI.Vc
} hli10p$
}else{
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this.totalCount = 0; /BM1AV{s6
} Nz*sD^SJa
} |Vi&f5p,@
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publicint[] getIndexes(){ (:QQ7xc{}
return indexes; n*Vd<m;w
} +5[oY,^cO
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publicvoid setIndexes(int[] indexes){ }4SSo)Uv/
this.indexes = indexes; hXm}d\
} b`W*vduf
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publicint getStartIndex(){ DYlvxF`
return startIndex; -l H>8+
} ).C!
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publicvoid setStartIndex(int startIndex){ #}dVaXY)
if(totalCount <= 0) -fJ@R1]
this.startIndex = 0; l&*)r;9
elseif(startIndex >= totalCount) =`~Z@IbdI
this.startIndex = indexes kQVDC,d
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[indexes.length - 1]; -I-Uh{)j
elseif(startIndex < 0) 9xn23*Fo
this.startIndex = 0; UVc<C
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else{ t-i6 FS-
this.startIndex = indexes Jh4&Qh|t
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[startIndex / pageSize]; NOr
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} ^YR|WK Y
} qzA]2'~Q
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publicint getNextIndex(){ [OZ=iz.
int nextIndex = getStartIndex() + ^8NLe9~p3?
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pageSize; eR-=<0Iw;
if(nextIndex >= totalCount) q{cp|#m#G
return getStartIndex(); #[a"%byTR
else ]hE+$sKd
return nextIndex; Vp$wHB&
} $iqi:vY
bug Fl>
publicint getPreviousIndex(){ j\'+wVyo
int previousIndex = getStartIndex() - 8.CKH4h
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pageSize; -/UXd4S
if(previousIndex < 0) lMwk.#
return0; Kr/h`RM
else 8jggc#.
return previousIndex; Ty3CBR{6
} t0e{|du
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} lMBX!9z
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抽象业务类 3+(yI 4
java代码: T2DF'f3A
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/** w dGpt_
* Created on 2005-7-12 SqXy;S@
*/ &@YFje6Lcm
package com.javaeye.common.business; D[89*@v
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import java.io.Serializable; qGnPnQc
import java.util.List; nTys4R
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import org.hibernate.Criteria; )o#6-K+b
import org.hibernate.HibernateException; `]`=]*d
import org.hibernate.Session; AqV09 $
import org.hibernate.criterion.DetachedCriteria; &|Lh38s@$#
import org.hibernate.criterion.Projections; +`;+RDKY*
import N[qA2+e$Z
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org.springframework.orm.hibernate3.HibernateCallback; s0cs'Rg
import nJFk4v4:2
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org.springframework.orm.hibernate3.support.HibernateDaoS "jL1.9%"
tJ=3'?T_k
upport; #^|| ]g/N
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import com.javaeye.common.util.PaginationSupport; !1a}| !Zn
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public abstract class AbstractManager extends j4;Du>obQ
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HibernateDaoSupport { <7=&DpjI7F
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privateboolean cacheQueries = false; NWEhAj<w
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privateString queryCacheRegion; h&lyxYZ+T$
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publicvoid setCacheQueries(boolean 7MY)\aH
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cacheQueries){ m</]D WJ
this.cacheQueries = cacheQueries; }>2t&+v+
} -=>sTMWpr
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publicvoid setQueryCacheRegion(String 0 _Q*E3
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queryCacheRegion){ glv ;C/l
this.queryCacheRegion = }@d>, 1DU
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queryCacheRegion; 'gCJ[ ce
} gs?8Wzh90*
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publicvoid save(finalObject entity){ 3 m6$YWO
getHibernateTemplate().save(entity); pvlDjj}
} swttp`
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publicvoid persist(finalObject entity){ E W`W~h[
getHibernateTemplate().save(entity); jDR')ascn
} FJ{=2]x|
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publicvoid update(finalObject entity){ d$w(-tV42
getHibernateTemplate().update(entity); ~i%-WX
} 1\/{#c
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publicvoid delete(finalObject entity){ ton1oq
getHibernateTemplate().delete(entity); %NNj9Bl<VV
} DKX/W+#a
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publicObject load(finalClass entity, 7%e1cI
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finalSerializable id){ yq?]V7~
return getHibernateTemplate().load kd yAl,
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(entity, id); rWA6XDM7
} I?B,sl_w
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publicObject get(finalClass entity, ML=eL*}l
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finalSerializable id){ `?l3Ct*
return getHibernateTemplate().get 6D|p Qs
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(entity, id); g0PT8]8
} Xx_tpC?
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publicList findAll(finalClass entity){ tAERbiH
return getHibernateTemplate().find("from Lbcy:E*g
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" + entity.getName()); ,]ga[
} =NadAyv
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publicList findByNamedQuery(finalString /,!<Va;~
Q^L)
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namedQuery){ 3f"C!l]Xu
return getHibernateTemplate +
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().findByNamedQuery(namedQuery); jXixVNw
} e?b)p5g
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publicList findByNamedQuery(finalString query, ZWS2q4/S
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finalObject parameter){ V C-d0E0
return getHibernateTemplate => qTNh*'
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().findByNamedQuery(query, parameter); eNbpwne
} 2VA!&`I
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publicList findByNamedQuery(finalString query, )qv2)a!H
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finalObject[] parameters){ yrnv!moc%t
return getHibernateTemplate `rlk|&T1
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().findByNamedQuery(query, parameters); A|L'ih/
} iPvuz7j=h
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publicList find(finalString query){ f"dSr
return getHibernateTemplate().find s3:9$.tiR[
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(query); :S -";.:"
} DN_W.o
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publicList find(finalString query, finalObject <F(><Xw,-4
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parameter){ wksl0:BL
return getHibernateTemplate().find :QPf~\w?
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(query, parameter); MLr-,
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} ,$N#Us(Wa
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public PaginationSupport findPageByCriteria -_em%o3XC
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(final DetachedCriteria detachedCriteria){ eM2|c3/
return findPageByCriteria 'RbQj}@x
* ?]~
#
(detachedCriteria, PaginationSupport.PAGESIZE, 0); Ji?#.r`"n
} wMWW=$h#\
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public PaginationSupport findPageByCriteria T.ML$"f
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(final DetachedCriteria detachedCriteria, finalint A%XX5*
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startIndex){ v-Qmx-N
return findPageByCriteria wNYg$d0M
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(detachedCriteria, PaginationSupport.PAGESIZE, S\*`lJzPM
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startIndex); 2YlH}fnH
} j.%K_h?V5
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public PaginationSupport findPageByCriteria ?6"{!s{v
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(final DetachedCriteria detachedCriteria, finalint -oP'4QVb
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pageSize, =5x&8i
finalint startIndex){ Lja 7
return(PaginationSupport) %JyXbv3m,
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getHibernateTemplate().execute(new HibernateCallback(){ />44]A<
publicObject doInHibernate ,|h)bg7.
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(Session session)throws HibernateException { U*)m',
Criteria criteria = oD.r`]k
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detachedCriteria.getExecutableCriteria(session); )Xtnk
int totalCount = -7{$Vj
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((Integer) criteria.setProjection(Projections.rowCount u0Nm.--;_3
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()).uniqueResult()).intValue(); !EIjN
criteria.setProjection 1P(&J
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(null); ~xLJe`"JUx
List items = %$5H!!~o
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criteria.setFirstResult(startIndex).setMaxResults ~Z'w)!h
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(pageSize).list(); {{yZ@>o6
PaginationSupport ps = D5,P)[
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new PaginationSupport(items, totalCount, pageSize, ,Lr<)p
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startIndex); S* *oA 6
return ps; /JkC+7H4
} qIMA6u/
}, true); De&6 9
} .iD*>M:W
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public List findAllByCriteria(final T r0B[QF
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DetachedCriteria detachedCriteria){ i0jBZW"_1$
return(List) getHibernateTemplate Bi,;lR5
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().execute(new HibernateCallback(){ [`RX*OH2
publicObject doInHibernate \QE)m<GUe
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(Session session)throws HibernateException { ]X Z-o>+,
Criteria criteria = %zk$}}ti.
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detachedCriteria.getExecutableCriteria(session); 7R!5,Js+
return criteria.list(); ??60,m:]
} ={>Lrig:l
}, true); $37
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} %ru;;h
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public int getCountByCriteria(final E.|-?xQ6
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DetachedCriteria detachedCriteria){ c(;a=n(E#
Integer count = (Integer) DwHF[]v'
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getHibernateTemplate().execute(new HibernateCallback(){ >9e(.6&2XZ
publicObject doInHibernate 5NoI~X=
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(Session session)throws HibernateException { I`KQ|h0%
Criteria criteria = w }^ I
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detachedCriteria.getExecutableCriteria(session); } :=Tm]S
return `K~AhlJUQ
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criteria.setProjection(Projections.rowCount B33$pUk
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()).uniqueResult(); :G\<y
} b2b?hA'k
}, true); o*U]v
return count.intValue(); =0uAE7q(9
} !$N<ds.
} EnOU?D
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用户在web层构造查询条件detachedCriteria,和可选的 H"ZZ.^"5FV
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 m3Il3ZY.
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PaginationSupport的实例ps。 2{|h8oz
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ps.getItems()得到已分页好的结果集 2^8%>,
ps.getIndexes()得到分页索引的数组 cuy1DDl
ps.getTotalCount()得到总结果数 zg-2C>(6a
ps.getStartIndex()当前分页索引 jck}" N
ps.getNextIndex()下一页索引 ys 5&PZg*
ps.getPreviousIndex()上一页索引 Vz6Qxd{m3
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 @v}/zS
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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 \=_{na_
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一下代码重构了。 0}_[DAd6
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我把原本我的做法也提供出来供大家讨论吧: gz3pX#S
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首先,为了实现分页查询,我封装了一个Page类: Qxj JN^Q
java代码: fbUr`~Y"
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/*Created on 2005-4-14*/ ?lP':'P
package org.flyware.util.page; E*+{t~
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/** L|p
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* @author Joa Ol!ntNhXm
* _%QhOY5tv"
*/ 6F e34n]m
publicclass Page { `r?7oxN
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/** imply if the page has previous page */ JH7<
privateboolean hasPrePage; &RfC"lc
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/** imply if the page has next page */ e=.]F*:J
privateboolean hasNextPage; ght$9>'n
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/** the number of every page */ R=jI?p
privateint everyPage; x&0vKo;
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/** the total page number */ M3q|l7|9
privateint totalPage; MG.`
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/** the number of current page */ Dd\jHF>u
privateint currentPage; R
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/** the begin index of the records by the current AJ=qn a
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query */ @ta7"6p-i@
privateint beginIndex; 13>0OKg`#
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/** The default constructor */ O&Y*pOg
public Page(){ pej|!oX
4T ~}
} 62zYRs\Y)X
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/** construct the page by everyPage =|Y,+/R?
* @param everyPage P}4QQw
* */ .4E&/w+
public Page(int everyPage){ .nVa[B|.
this.everyPage = everyPage; BBev<
} T
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/** The whole constructor */ U[ 0=L`0e
public Page(boolean hasPrePage, boolean hasNextPage, va0{>Dc+
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int everyPage, int totalPage, ojanBg
int currentPage, int beginIndex){ Ck)*&
this.hasPrePage = hasPrePage; s6@DGSJ
this.hasNextPage = hasNextPage; p"KFJ
this.everyPage = everyPage; ++^l]8
this.totalPage = totalPage; B&n<M]7
this.currentPage = currentPage; ]jo1{IcI
this.beginIndex = beginIndex; 0E3[N:s
} 0"pAN[=K@
!]=d-RGNe
/** sG92XJ
* @return r2,.abo
* Returns the beginIndex. N(Fp0
*/ Tu).K.p:
publicint getBeginIndex(){ AHX St
return beginIndex; LhA/xf
} pu2tY7Ja
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/** @}}$zv6l,
* @param beginIndex ;6>2"{NW
* The beginIndex to set. ]7Tkkw$
*/ (KDD e}f
publicvoid setBeginIndex(int beginIndex){ J1C3&t}
this.beginIndex = beginIndex; gaZu;t2u
} -;^j:L{
)-a'{W/t
/** &E.^jR~*
* @return ewctkI$,5
* Returns the currentPage. t.xxSU5~%
*/ AP'*Nh@Ik(
publicint getCurrentPage(){ I|^;B8[
return currentPage; B><d9d
} iKX-myCz
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/** _./Sk|C
* @param currentPage 1;Ou7T9w
* The currentPage to set. wea-zN
*/ b4[bL2J$h1
publicvoid setCurrentPage(int currentPage){ H9YW
this.currentPage = currentPage; /`wvxKX
} PHZ0P7
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/** J IUx
* @return JB<Sl4
* Returns the everyPage. um!J]N^
*/ \hDlTp}
publicint getEveryPage(){ H4:`6 PSL
return everyPage; |}=acc/
} _Xk.p_uh
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/** 5Co
* @param everyPage F8jd'OR
* The everyPage to set. -p]1=@A<}
*/ D1zBsi94D
publicvoid setEveryPage(int everyPage){ p@xf^[50k
this.everyPage = everyPage; _m5uDF?[
} _K l_61k
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/** >=:&D)m"
* @return ILEz;D{]
* Returns the hasNextPage. VVac:
*/ d3ZdB4L
publicboolean getHasNextPage(){ 1w@(5 ^V
return hasNextPage; TN+iA~kQ
} v+46QK|I&
/:~\5}tW
/** 6e9,PS
* @param hasNextPage +6HVhoxU#
* The hasNextPage to set. [>8}J"
*/ k/#&qC>]
publicvoid setHasNextPage(boolean hasNextPage){ l;R%= P?'F
this.hasNextPage = hasNextPage;
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} q&s3wDl/
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/** KL1/^1
* @return \^L`7cBL
* Returns the hasPrePage. 8 OY 3A
*/ ]zE;Tw.S
publicboolean getHasPrePage(){ [^Os kJ4
return hasPrePage; *W,]>v0%T
} .}t~'*D
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/** #5cEV'm;
* @param hasPrePage Cl;oi}L
* The hasPrePage to set. Rdvk
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*/ vQosPS_2L
publicvoid setHasPrePage(boolean hasPrePage){ \?[v{WP)
this.hasPrePage = hasPrePage; LClNxm2X
} cv998*|X:
Ktb\ b w
/** >`Y.+4mE
* @return Returns the totalPage. #hfXZVD
* <"{qk2LS1
*/ Uzz'.K(Mv|
publicint getTotalPage(){ rI= v
return totalPage; be]bZ
1f
} Tl(^
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/** *SU\ABcov
* @param totalPage U`R5'Tf;
* The totalPage to set. ZZ2vvtlyG
*/ `Nz/Oh7
publicvoid setTotalPage(int totalPage){ &]"
this.totalPage = totalPage; ")O%86_Q:
} [Y|8\Ph`&
~ELNyI11
} 2`7==?
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v\KA'PmiP
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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 d4u})
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个PageUtil,负责对Page对象进行构造: 6IBgt!=,
java代码: Yw4n-0g
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/*Created on 2005-4-14*/ QS%%^+E2
package org.flyware.util.page; nygbt<;?
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import org.apache.commons.logging.Log; aZ2!i
import org.apache.commons.logging.LogFactory; RN$1bxY
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/** K(q+
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* @author Joa ]$ L|
* 'n{Nvt.c
*/ +c(zo4nZ
publicclass PageUtil { ^T*? >%`
![`Ay4AZ@a
privatestaticfinal Log logger = LogFactory.getLog vI:;A/&
jr)1(**
(PageUtil.class); v*'^r)Q[p
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/** }SX,^|eN
* Use the origin page to create a new page ?u{~>
* @param page |v \_@09=
* @param totalRecords /xsF90c\h
* @return }+)fMZz
*/ &~8oQC-eF
publicstatic Page createPage(Page page, int N >FKy'.gk
!TAlBkj
totalRecords){ f%SZg!+t
return createPage(page.getEveryPage(), [b6R%
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page.getCurrentPage(), totalRecords); _wTOmz%|R
} sPr~=,F
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/** CnpV:>V=
* the basic page utils not including exception *!q1Kr6r
C`$n[kCJ
handler l n{e1':$"
* @param everyPage 8K.R=
* @param currentPage 7op`s5i
* @param totalRecords &+cEV6vb+
* @return page iIMd!Q.)@
*/ ~D<IB#C
publicstatic Page createPage(int everyPage, int D&od?3}E
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currentPage, int totalRecords){ K~AR*1??[
everyPage = getEveryPage(everyPage); Gr7=:+0n|P
currentPage = getCurrentPage(currentPage); !Y$h"<M
int beginIndex = getBeginIndex(everyPage, -wp|RD,}(
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currentPage); BUWqIdg
int totalPage = getTotalPage(everyPage, 0+?7EL~
OBMTgZHxv
totalRecords); kO,zZF&
boolean hasNextPage = hasNextPage(currentPage, 5"CZh.J
igIRSN}h
totalPage); 3N dq>
boolean hasPrePage = hasPrePage(currentPage);
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returnnew Page(hasPrePage, hasNextPage, GC?ON0g5s
everyPage, totalPage, /JFUU[W
currentPage, `7 vHt`
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beginIndex); gYNjzew'
} xAK6pDp
lt
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privatestaticint getEveryPage(int everyPage){ FoNSM$x
return everyPage == 0 ? 10 : everyPage; 6N",-c
} c#|raXGT
nH`Q#ZFz]?
privatestaticint getCurrentPage(int currentPage){ {t0)
q
return currentPage == 0 ? 1 : currentPage; R%{a1r>9h
} Rtb7|
K@sV\"U(*E
privatestaticint getBeginIndex(int everyPage, int ,24p%KJ*X
}@;ep&b*
currentPage){ UELy"z
R
return(currentPage - 1) * everyPage; x,rlrxI
} VXYK?Qc'
S& SQ
privatestaticint getTotalPage(int everyPage, int OHeT,@(mh
[Grxw[(_:
totalRecords){ T+*%?2>q"
int totalPage = 0; 6%t1b M
a
o<[#0T^K
if(totalRecords % everyPage == 0) *G{^|z
totalPage = totalRecords / everyPage; ePr&!Tz#
else GO__$%~
totalPage = totalRecords / everyPage + 1 ; 55tKTpV
{ vKLAxc
return totalPage; n&"B0y cF
} P,xKZ{(
4? ICy/,U-
privatestaticboolean hasPrePage(int currentPage){ gLE:g5v6
return currentPage == 1 ? false : true; I,0q4
} JBi*P.79^
V#XppYU
privatestaticboolean hasNextPage(int currentPage, ,{BaePMp
s!?`T1L
int totalPage){ lBK}VU^
return currentPage == totalPage || totalPage == m;'6MHx;
PK{acen
0 ? false : true; jF0jkj1&/[
} {)BTR %t
UmKI1l
iH/6M
} d{SG
Cr 9d
Jth[DUH8H
n@C[@?D
pimtiQqC
AyNI$Q6Z
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。 U^Q:Y}^
b6U2GDm\s
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 Y&S24aql
#:[t^}
做法如下: qv]}$WU
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 vgsJeV`}I
V!lZ\)
的信息,和一个结果集List: lr`&mZ( j
java代码: qAn! Rk A
pi
Z[Y
5OE
MCS8y+QK
/*Created on 2005-6-13*/ ;D:9+E<>a
package com.adt.bo; 7*
yzEM
*~t6(v?
import java.util.List; v.pBX<
tnPv70m
import org.flyware.util.page.Page; j6Yy6X]
K
P Oa|$
/** I1pWaQ0
* @author Joa aMtsmL?=
*/ JT3-AAi[Z
publicclass Result { ^>i63Yc
K_RjX>q%N
private Page page; +89*)pk
1guJG_;z
private List content; | N[<x@
t5y;CxL
/** NWMFtT
* The default constructor [R=yF ~-
*/ 3~uW I%I`
public Result(){ GT0Of~?f
super(); Jtr"NS?a]
} ~/98Id}v
L3@82yPo!
/** /J=v]<87a
* The constructor using fields RxI(:i?
* v^#~98g]
* @param page j`~Ms>
* @param content kQEy#JQmB
*/ tasUZ#\6
public Result(Page page, List content){ BW 4%l
this.page = page; 9{
>Ui
this.content = content; .^h#_[dp
} U56G.
G LIi6
/** H@%GSE
* @return Returns the content. @cFJeOC|
*/ czS+<
w
publicList getContent(){ S7/eS)SQR
return content; uTKD 4yig
} 2QJ{a46}
dwDcR,z?a
/** u*Pibgd<
* @return Returns the page. J|~MC7#@q
*/ ?}kG`q
public Page getPage(){ hRUhX[
return page; ~N<4L>y<
} z([ v%zf
7f0lQ
/** zi]\<?\X
* @param content &Low/Y'.jJ
* The content to set. s'%R
*/
TU:7Df
public void setContent(List content){ ^eo|P~w
g
this.content = content; 59"UL\3
} 3|'>`!hb
" @v <Bk
/** p<,*3huj
* @param page M$/|)U'W
* The page to set. ^j31S*f&:
*/ +^=8ge}
publicvoid setPage(Page page){ 56zL"TF`
this.page = page; UA48Ug
} *>n;SuT_
} 6L"%e!be6
Z0Vl+
|mGFts}0o'
$}>+kHoT{
+@p%
p
2. 编写业务逻辑接口,并实现它(UserManager, mLP.t%?#
y5*Z3"<
UserManagerImpl) =a@j=
java代码: x{n`^;Y1
l5Gq|!2yxD
P<X\%_Iat
/*Created on 2005-7-15*/ 60J;sGW
package com.adt.service; H!5\v"]WB
nxWY7hU
import net.sf.hibernate.HibernateException; ]:Nsf|C0
Yu)NO\3&
import org.flyware.util.page.Page; f!I[>&n
psg)*'r
import com.adt.bo.Result; >8WP0Qx/
]:4*L
/** Ju96#v+:
* @author Joa ]rWgSID
*/ S|7!{}
publicinterface UserManager { WvBc#s-
ow_W%I=6
public Result listUser(Page page)throws {2=jAz'?
A OISs4
HibernateException; mH%yGBp_
-likj#Z
} x:),P-~w
m[~V/N3
Xejo_SV&?
>qS9PX
5-aj2>=7
java代码: x[h^[oF0
bwD,YC
S ?{#r
/*Created on 2005-7-15*/ zsX1 QN16
package com.adt.service.impl; Z>)Bp/-
f&BY/ n,
import java.util.List; x=b7': nQ
,z;cbsV-{
import net.sf.hibernate.HibernateException; ]P.'>4
:=u?Fqqws
import org.flyware.util.page.Page; xe{!wX
import org.flyware.util.page.PageUtil; x3 q]I 8q
^@3sT,M,S
import com.adt.bo.Result; sz:g,}~h
import com.adt.dao.UserDAO; fVF2-Rh=
import com.adt.exception.ObjectNotFoundException; n>ULRgiT:o
import com.adt.service.UserManager; WY?[,_4U
=G7m)!
/** cq}EZ@ .
* @author Joa `A w^H!
*/ .
$BUw
publicclass UserManagerImpl implements UserManager { xF;kTBRi
oW ::hB
private UserDAO userDAO; s5CXwM6cx
C-Q28lD}f
/** , w{e
* @param userDAO The userDAO to set. wSa)*]%
*/ &dM.
d!
publicvoid setUserDAO(UserDAO userDAO){ 0AZ")<^~7
this.userDAO = userDAO; ZCmgs4W!
} lR )67a
.E`\MtA
/* (non-Javadoc) |bTPtrT8
* @see com.adt.service.UserManager#listUser G`cHCP_n
ZrPbl"`7
(org.flyware.util.page.Page) KN<S}3MN
*/ /N =b\-]
public Result listUser(Page page)throws jrr EAp
a1EOJ^}0
HibernateException, ObjectNotFoundException { }>>1<P<8-
int totalRecords = userDAO.getUserCount(); rp3V3]EE
if(totalRecords == 0) L
6c 40
throw new ObjectNotFoundException @.$| w>>T
I'A_x$ib6
("userNotExist"); b*a#<K$T_
page = PageUtil.createPage(page, totalRecords); X{5vXT\/y
List users = userDAO.getUserByPage(page); S\:P-&dC
returnnew Result(page, users); ZP@
$Q%up
} >0/i[k-dk
q!.byrod
} )
i;1*jK
~IYUuWF(
- Ajo9H
] eotc2?u
jyZ (RB
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 aS{|uE]
l3Xfc2~ 2
询,接下来编写UserDAO的代码: ((H^2KJn
3. UserDAO 和 UserDAOImpl: t<#TJ>Le
java代码: th
O#ai)e_uQk
??^5;P{yx
/*Created on 2005-7-15*/ GWZ
}7ake
package com.adt.dao; uxXBEq;
J%u=Ucdh
import java.util.List; 0(eBZdRO
a L} %2
import org.flyware.util.page.Page; J"!vu.[
'~5LY!H(pT
import net.sf.hibernate.HibernateException; NCiW^#b
*Fy2BZH%Q
/** |,S+@"0#
* @author Joa a!a-b~#cx
*/ T-.%
publicinterface UserDAO extends BaseDAO { Bal$+S
GzhYY"iif#
publicList getUserByName(String name)throws J?V? R
`` ,fodA8
HibernateException; gZN8!#h}B
9B{k , 1
publicint getUserCount()throws HibernateException; CSJdvxb
{#ZlM
publicList getUserByPage(Page page)throws *:Y%HAy*
RSfQNc9Z
HibernateException; 2GP=&K/A
PC~Y8,A|.t
} ,|3MG",@@h
^X=arTE
&*##bA"!B
<fZyAa3}
H3z:ZTI
java代码: {x|[p_?
8m-U){r!U^
\HqNAE2T
/*Created on 2005-7-15*/ t)~"4]{*}D
package com.adt.dao.impl; @@R7p
,BH@j%Jmy
import java.util.List; z6U\axO6
IbT=8l,Li
import org.flyware.util.page.Page; W<bGDh
P@Hs`=
import net.sf.hibernate.HibernateException; w^Sz#_2
import net.sf.hibernate.Query; CNih6R
U_Vs.M.p
import com.adt.dao.UserDAO; `tBgH_$M
y^;#&k!
/** x.]i}mt
* @author Joa Q8T]\6)m
*/ 1#C4;3i,
public class UserDAOImpl extends BaseDAOHibernateImpl b,5~b&<h
.8@$\ZRP
implements UserDAO { v_BcTzQ0S
gR&Q3jlIV
/* (non-Javadoc) SzAJ2:qhl
* @see com.adt.dao.UserDAO#getUserByName ! +a. Ei
y=fx%~<>
8
(java.lang.String) G/k2Pe{SL
*/ vleS2-]|
publicList getUserByName(String name)throws XeW<B0~
!<j'Ea
HibernateException { |nc@"OJ
String querySentence = "FROM user in class %>yG+Od5Z
B\=L3eL<D
com.adt.po.User WHERE user.name=:name"; UxbjA- U[
Query query = getSession().createQuery 6@Y_*4$|
VF&(8X\
(querySentence); ojafy}
query.setParameter("name", name); A0/"&Ag]
return query.list(); &TnS4O
} S*==aftl(
];VA!++
/* (non-Javadoc) Q!o'}nA
* @see com.adt.dao.UserDAO#getUserCount() -C;^3R[
O
*/ m!gz3u]rN
publicint getUserCount()throws HibernateException { wVX[)E\J
int count = 0; :{PJI,
String querySentence = "SELECT count(*) FROM r(6Y*<
6w*dKInG[-
user in class com.adt.po.User"; x/NfZ5e0X
Query query = getSession().createQuery O(#)m>A
&T+atL `N
(querySentence); %D UH@j
count = ((Integer)query.iterate().next Z 6t56"u
"fQ~uzg="
()).intValue(); Pnk5mK$
return count; yg`j-9[8
} {}>0e:51
f~t:L,\,
/* (non-Javadoc) ^?-:'<4q$
* @see com.adt.dao.UserDAO#getUserByPage Ye\rB\-
S{Kiy#ltWc
(org.flyware.util.page.Page) 61Bwb]\f/|
*/ }d[ kxo
publicList getUserByPage(Page page)throws bbtGXfI+SB
18)'c?^.
HibernateException { 3]OE}[R
String querySentence = "FROM user in class o~U$GBg
H7?Vy bg~
com.adt.po.User"; ++bf#qS<8D
Query query = getSession().createQuery v6[!o<@"a
c%^7!FSg
(querySentence); T%x}Y#U'`
query.setFirstResult(page.getBeginIndex()) |Z|-q"Rf
.setMaxResults(page.getEveryPage()); |+"<wEKI
return query.list(); niiA7Ux
} ySk R>y
sz5MH!/PJ
} fWCo;4<5?
x5|I
%G3h?3
FGPB:
m- %E-nr
至此,一个完整的分页程序完成。前台的只需要调用 N/[p <
#=D) j
userManager.listUser(page)即可得到一个Page对象和结果集对象 :<ka3<0%
<vnHz?71c
的综合体,而传入的参数page对象则可以由前台传入,如果用 mH54ja2
5 z~1Dw
webwork,甚至可以直接在配置文件中指定。 __lM7LFL
,oORW/0iS
下面给出一个webwork调用示例: d)B@x`
java代码: @*F"Q1 wI
b}OY4~ Y4
~9?cn
/*Created on 2005-6-17*/ Av @b!iw+
package com.adt.action.user; Y_Eb'*PY
wGU*:k7p
import java.util.List; Hj'x Atx5
_ftI*ni:<
import org.apache.commons.logging.Log; R]Vt Y7}i,
import org.apache.commons.logging.LogFactory; G
!<Z.]
import org.flyware.util.page.Page; ~Xw"}S5
LnFdhrB@x
import com.adt.bo.Result; 7WZrSC
import com.adt.service.UserService; B5gj_^
import com.opensymphony.xwork.Action; jLy
tN[L@t9#cr
/** _geWE0
E
* @author Joa #m lS}~n
*/ Hh%I0#
publicclass ListUser implementsAction{ yTyj'-4
cO-7ke
privatestaticfinal Log logger = LogFactory.getLog |$+3a
ZkgV_<M|
(ListUser.class); G=)i{oC
+QB"8-
private UserService userService; IWBX'|}K
> pgX^
private Page page; jy7\+i
MtM%{=&_
privateList users; y9_V
~aw.(A?MI
/* Dw|}9;5:A
* (non-Javadoc) uzXCIv@
* iz5CAxm
* @see com.opensymphony.xwork.Action#execute() '#!
gh?
*/ {Z{75}
publicString execute()throwsException{ TH)"wNa
Result result = userService.listUser(page); hrmut*<|
page = result.getPage(); yhlFFbU
users = result.getContent(); OL5v).Bb
return SUCCESS; T}
`x-
} bf0+DvIB
)Z[ft
/** w^(<N7B3T
* @return Returns the page. ml2_
]3j!
*/ :WC2Ax7$2
public Page getPage(){ t4{rb,
}W
return page; &6DMk-
} 1h(0IjG8
D@C-5rmq
/** :Y-{Kn6`_
* @return Returns the users. }p=Jm)y
*/ ,?PTcQF
publicList getUsers(){ %el"BSB
return users; YpQ7)_s?
} g!cUF+
R{RwTN<
/** k")R[)92b?
* @param page Z/Eb:
* The page to set. <wZQc
*/ =5aDM\L$&
publicvoid setPage(Page page){ soPLA68
this.page = page; ]&?Y~"{cD
} 3WN`y8l
"rTQG6`
/** Q)"C&)`l
* @param users 0YaA `
* The users to set. k $M]3}$U
*/ Yj%U
>),8
publicvoid setUsers(List users){ z
MLK7+
this.users = users; b6W2^tr-
} |lXc0"H[o
h"`ucC8X
/** |}23>l7
* @param userService `(T,+T4C5k
* The userService to set. v. %R}Pa
*/ -g)9R%>-
publicvoid setUserService(UserService userService){ UU'|Xz9~
this.userService = userService; r`%+M7
} @95FN)TXZY
} syk!7zfK
L}GC<D:
=,%CLS,6w
zs%Hb48V
1[kMOp
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, 0$_oT;{8
.tkT<o-u<J
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 :!/gk8F|dI
Fd?"-
么只需要: C(S'#cm
java代码: ~jK{ ,$:=
dX\.t<
v4?x.I
<?xml version="1.0"?> ZPc@Zr`z
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ?aC'.jH+
(* 1v\Q
1.0//EN" "http://www.opensymphony.com/xwork/xwork- \2nUa
;
UUF;p2{f
1.0.dtd"> KQcs3F@t
DvPlV q~
<xwork> cKN$ =gd
aUxGzMZ
<package name="user" extends="webwork- a,3j,(3
:,WtR
interceptors"> Kk(9O06j
0OT\"O~S[
<!-- The default interceptor stack name HQ|MhM/"
Vm5c+;
--> kxp);
<default-interceptor-ref ?6(I V]
BJgW,huLy
name="myDefaultWebStack"/> N-jTc?mT~&
9Rn?
:B~W:
<action name="listUser" +zrAG24q
`Q+(LBP
class="com.adt.action.user.ListUser"> \ {qI4=
<param rSxxH]-
F.-R r
name="page.everyPage">10</param> !_+8A/
<result N>Eqj>G
'; = f
name="success">/user/user_list.jsp</result> %)[+%57{
</action> KBXK0zWh7
B;R.# ^@/
</package> +j(d| L\
ysmNio
</xwork> (
{1e%
Dq36p${\W
Vw#_68EybM
3uZJ.Fb
'eo
KZX+
D\@m6=L
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 aO@7O*
"z0zpHXek
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 Ma'_e=+A
V[}4L|ad
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 %q!8={J8
T[,/5J
FP0G]=ME
{r>.G7P6
{%VV\qaC
我写的一个用于分页的类,用了泛型了,hoho [zL7Q^~
6ZKsz5:=
java代码: JJltPGT~Oa
:(a]V"(&Eq
e1>aTu@
package com.intokr.util; !
iptT(2
%V1Z~HC
import java.util.List; P6 ;'Sza
Di@GY!
/** N[<H7_/3
* 用于分页的类<br> r'dr9"-{
* 可以用于传递查询的结果也可以用于传送查询的参数<br> "p/j; 6H
* /,MJq#@K
* @version 0.01 d~/q"r 1"
* @author cheng JCPUM*g8
*/ t^xTFn
public class Paginator<E> { v1|Bf8
privateint count = 0; // 总记录数 ^ K7ic,{
privateint p = 1; // 页编号 %.<H=!$
privateint num = 20; // 每页的记录数 JOb*-q|y
privateList<E> results = null; // 结果 j:}J}P
:}h>by=
/** rQOWLg!"
* 结果总数 uGwJK`!~
*/ h)6GaJ=
publicint getCount(){ d{3@h+zL
return count; $`8Ar,Xz`
} /^$UhX9v
3#vinz
publicvoid setCount(int count){ T;diNfgg
this.count = count; OdQT2PA_
} hY*0aZ|(
%*o8L6Hn
/** b1gaj"]
* 本结果所在的页码,从1开始 6
4D]Ypx
* uk9g<<3T
* @return Returns the pageNo. 'lo
*/ jYVE8Y)my
publicint getP(){ (=16PYs
return p; )jCo%P/
} TgTnqR@/
zf.-I
/** x lsqj`=
* if(p<=0) p=1 R#n%cXc|
* B/J>9||g
* @param p QN>7~=`
*/ uNHdpni
publicvoid setP(int p){ e8h,,:l3j
if(p <= 0) _1*7Z=|
p = 1; '.Ym!r~wL
this.p = p; KECElK3uj
} B51kV0
-h-oMqgu(
/** {kLGWbo|Q
* 每页记录数量 `W `0Fwu9
*/ Sd))vS^g
publicint getNum(){ T#!lPH :&h
return num; pi5GxDA]
} _P,^_%}V06
.>Z,uT^A
/** r]P, 9
* if(num<1) num=1 Nt:8ogk/
*/ w%c
publicvoid setNum(int num){ maSgRf[g
if(num < 1) J^m<*
num = 1; sT1&e5`W
this.num = num; ;pJ2V2 g8
} ogeL[7
h?UVDzI!O
/** a
:HNg
* 获得总页数 ;`v% sx#
*/ }:z5t,u6
publicint getPageNum(){ `nJu?5
return(count - 1) / num + 1; Y\+KoR';
} u-DK_^v4M
Rt(J/%;
/** =l942p
* 获得本页的开始编号,为 (p-1)*num+1 d"~(T:=r
*/ rrs"N3!aT
publicint getStart(){ 99OD=pxQ
return(p - 1) * num + 1; 7Bz*r0 9S
} ~VTs:h
Y7U&Q:5'
/**
1;| LI?
* @return Returns the results. 2GWDEgI1o
*/ b^`AJK
publicList<E> getResults(){ *s)}Bj
return results; Eff\Aq{
} F6S~$<
4B-yTyO
public void setResults(List<E> results){ r;iV$Rq!
this.results = results; *(GZ^QH.
} 8v
yG*UK
)%Y
IGV;&
public String toString(){ Di=9mHC
StringBuilder buff = new StringBuilder beZ(o?uK
oP,9#FC|(
(); t7F.[uWD
buff.append("{"); !0 Q8iW:
buff.append("count:").append(count); 3+YbA)i;
buff.append(",p:").append(p); h ?#@~
buff.append(",nump:").append(num); jB@4b'y
buff.append(",results:").append !rTmR@e$/
(:\LWJX0=
(results); G+"8l!dC?
buff.append("}"); (U87}}/l
return buff.toString(); ;RN8\re
} R[A5JQ$[
[cU,!={
} aW{L7N %
EZ#gp^$
8&}~'4[b[$