Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 M#%l}
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 x7\b-EC
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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 1T&NU
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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 )!z4LE
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分页支持类: )Y4;@pEU
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java代码: e1cqzhI=nA
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package com.javaeye.common.util; eX)'C>4W
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import java.util.List; O-P'Ff"}t
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publicclass PaginationSupport { zF:
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publicfinalstaticint PAGESIZE = 30; +;r1AR1)x
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privateint pageSize = PAGESIZE; "x1?T+j4
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privateList items; 75v7w
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privateint totalCount; eX`wQoV%
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privateint[] indexes = newint[0]; e= { ?d6
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privateint startIndex = 0; i~Q nw-^B
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public PaginationSupport(List items, int qa-%j +
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totalCount){ z
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setPageSize(PAGESIZE); ,~Y[XazT
setTotalCount(totalCount); ]@Z[/z%~04
setItems(items); r:{;HM+
setStartIndex(0); oYx4+xH/
} Ml,~@}
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public PaginationSupport(List items, int {Jbouj?V!
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totalCount, int startIndex){ ^%5;Sc1V
setPageSize(PAGESIZE); _tlr8vL
setTotalCount(totalCount); tt4Z
setItems(items); `d c&B
setStartIndex(startIndex); g)!d03Qoy
} \jmT#Gt`9
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public PaginationSupport(List items, int z`H|]${X
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totalCount, int pageSize, int startIndex){ Ly46S
setPageSize(pageSize); >O]u4G!
setTotalCount(totalCount); !w1acmo<_
setItems(items); y3XR:d1cg
setStartIndex(startIndex); }|UTwjquBD
} Vp$<@Y
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publicList getItems(){ G^ShN45
return items; vRkVPkZ6|
} V~#8lu7;
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publicvoid setItems(List items){ Gq=tR `.
this.items = items; !L[$t~z
} 8B?*?,n5
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publicint getPageSize(){ we0haK
return pageSize; ke<l@wO
} y_``-F&Z
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publicvoid setPageSize(int pageSize){ \E
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this.pageSize = pageSize; $~e55X'!+
} ?
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publicint getTotalCount(){ #.<Dq8u
return totalCount; }wB!Bx2
} \zh`z/=92
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publicvoid setTotalCount(int totalCount){ )Vz=:.D
if(totalCount > 0){ 3qQ}U}-; |
this.totalCount = totalCount; _RNP_$a
int count = totalCount / XL/V>`E@
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pageSize; FM=XoMP q
if(totalCount % pageSize > 0) e%km}m A
count++; 5KNa-\
indexes = newint[count]; FKtG
for(int i = 0; i < count; i++){ Z*R~dHr
indexes = pageSize * !a4`SjOgu
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i; ]`q]\EH
} y*Gq VA[
}else{ ^V~^[Yp
this.totalCount = 0; R5i xG9
} _'|C-j`u$
} *V_b/Vt
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publicint[] getIndexes(){ +4n}H}9l
return indexes; >]HvXEdNZ|
} ta@fNS4
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publicvoid setIndexes(int[] indexes){ R2==<"gq
this.indexes = indexes; dy ~M5,zn
} ;Kh[6{ W
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publicint getStartIndex(){ %J+ w9Z
return startIndex; Spw^h=o
} 9!PM1<p
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publicvoid setStartIndex(int startIndex){ I^)_rOgM
if(totalCount <= 0) Rzyaicj^c
this.startIndex = 0; .NJ Ne
elseif(startIndex >= totalCount) cSBS38>
this.startIndex = indexes B1j^qoC.5
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[indexes.length - 1]; E#A}2|7,g
elseif(startIndex < 0) [s+FX5' K
this.startIndex = 0; :j#zn~7
else{ 6FX]b4
this.startIndex = indexes (tF/2cZk
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[startIndex / pageSize]; P_P~c~o
} V#B'm?aQ
}
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publicint getNextIndex(){ rM4Ri}bS
int nextIndex = getStartIndex() + cpPS8V
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pageSize; 9&HaEAme
if(nextIndex >= totalCount) #<@_mbQ@|K
return getStartIndex(); ?y@;=x!'
else |RBL5,t^
return nextIndex; a# Uk:O!
} J[UTn'M8]
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publicint getPreviousIndex(){ F ~e}=Nb
int previousIndex = getStartIndex() - a
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pageSize; kaRjv
if(previousIndex < 0) l}FA&c"
return0; W6)XMl}n
else x&N@R?AG1
return previousIndex; m;sYg
} U ZL-mF:)&
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} @7sHFwtar?
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抽象业务类 'N&s$XB,
java代码: :4>LtfA
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/** }5d|y*
* Created on 2005-7-12 :2lM7|@/
*/ Of
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package com.javaeye.common.business; m:g%5'qDZ
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import java.io.Serializable; SIzA0
import java.util.List; >?{>
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import org.hibernate.Criteria; o{7w&Pgs2
import org.hibernate.HibernateException; OYOczb]
import org.hibernate.Session; B~3qEdoK5`
import org.hibernate.criterion.DetachedCriteria; TrVQ]9;jWk
import org.hibernate.criterion.Projections; kqCUr|M.P
import b:&=W>r
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org.springframework.orm.hibernate3.HibernateCallback; bR=TGL&
import _2<k,Dl;RY
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org.springframework.orm.hibernate3.support.HibernateDaoS ?osYs<k \
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upport; =Q8$O
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import com.javaeye.common.util.PaginationSupport; jG^OF5.
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public abstract class AbstractManager extends mW."lzIl
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HibernateDaoSupport { :5zO!~\
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privateboolean cacheQueries = false; a@-!,Hi
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privateString queryCacheRegion; =l$qwcfbo
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publicvoid setCacheQueries(boolean <-|g>
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cacheQueries){ .7H*F9
this.cacheQueries = cacheQueries; BeM|1pe.
} m6
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publicvoid setQueryCacheRegion(String Q#I?nBin
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queryCacheRegion){ SG3qNM: g
this.queryCacheRegion = ?E7.x%n7X5
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queryCacheRegion; 7A>glZ/x
} >c@1UEwkm
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publicvoid save(finalObject entity){ dRLvej,
getHibernateTemplate().save(entity); xW'(]Z7_
} tJ9`Ys
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publicvoid persist(finalObject entity){ 2a:JtJLl
getHibernateTemplate().save(entity); rxAb]~MMp
} w24@KaKFo
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publicvoid update(finalObject entity){ zI3Bb?4.
getHibernateTemplate().update(entity); @&]%%o+
} 3+ r8yiY
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publicvoid delete(finalObject entity){ mkt%|Kb.
getHibernateTemplate().delete(entity); n>I
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} $F86Dwd
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publicObject load(finalClass entity, eI*o9k$Qs
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finalSerializable id){ HWT^u$a"
return getHibernateTemplate().load '#0'_9}
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(entity, id);
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} 3.s.&^
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publicObject get(finalClass entity, )F)
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finalSerializable id){ QGQ>shIeZ
return getHibernateTemplate().get P ||:?3IH
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(entity, id); m`Ver:{
} Ljjuf=]
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publicList findAll(finalClass entity){ &*N;yW""f
return getHibernateTemplate().find("from O
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" + entity.getName()); rt[w
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} qKg*/)sD(
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publicList findByNamedQuery(finalString nuip
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namedQuery){ '{?7\+o.x
return getHibernateTemplate iFy_D
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().findByNamedQuery(namedQuery); k*3F7']8
} <,!e*V*U
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publicList findByNamedQuery(finalString query, $ RDwy)9
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finalObject parameter){ JXIxk"m
return getHibernateTemplate $kA'9Y
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().findByNamedQuery(query, parameter); -6OgM}
} +(-L
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publicList findByNamedQuery(finalString query, kgV_*0^
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finalObject[] parameters){ x$;I E
return getHibernateTemplate _Fz]QxO
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().findByNamedQuery(query, parameters); +q/ j
} aIl}|n"
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publicList find(finalString query){ %9!,PeRe
return getHibernateTemplate().find R"9^FQ13
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(query); 3S~Gi,
} .MzVc42<
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publicList find(finalString query, finalObject \Y0o~JD
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parameter){ VM1`:1Z:$
return getHibernateTemplate().find ebSG|F
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(query, parameter); M6 W{mek
} \L"Vx9xT
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public PaginationSupport findPageByCriteria 0#AS>K5
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(final DetachedCriteria detachedCriteria){ /7
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return findPageByCriteria 4Y)rgLFj
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); q*|H*sS
} Sd!!1as
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public PaginationSupport findPageByCriteria 3$u3ssOL
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(final DetachedCriteria detachedCriteria, finalint \<}4D\qz
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startIndex){ arR9uxP
return findPageByCriteria D+Ke)-/
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(detachedCriteria, PaginationSupport.PAGESIZE, &p)]Cl/`
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startIndex); X2?
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} ZH:-.2*cj
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public PaginationSupport findPageByCriteria [\ M$a|K
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(final DetachedCriteria detachedCriteria, finalint yM*-em
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pageSize, ET_a>]<mv
finalint startIndex){ ] rP^
return(PaginationSupport) N:j,9p0,
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getHibernateTemplate().execute(new HibernateCallback(){ "0Wi-52=V
publicObject doInHibernate ! z^%$;p
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(Session session)throws HibernateException { qgT~yDm
Criteria criteria = EqN<""2
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detachedCriteria.getExecutableCriteria(session);
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int totalCount = `UC
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((Integer) criteria.setProjection(Projections.rowCount cmLGMlFT
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()).uniqueResult()).intValue(); 0W92Z@_GY
criteria.setProjection ,cgFdOM.
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(null); MX@t[{ Gg9
List items =
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criteria.setFirstResult(startIndex).setMaxResults _GoV\wGKl
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(pageSize).list(); X"4 :#s
PaginationSupport ps = >MuI-^3
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new PaginationSupport(items, totalCount, pageSize, ZA u=m
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startIndex); a'T8U1
return ps; |[)k5nUQ|
} 7#~v<M6
}, true); V`/E$a1&
} UlG8c~p
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public List findAllByCriteria(final qO;.{f
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DetachedCriteria detachedCriteria){ 9g7d:zG
return(List) getHibernateTemplate BHVC&F*>
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().execute(new HibernateCallback(){ |K|[>[?Z/
publicObject doInHibernate $+ z3
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(Session session)throws HibernateException { hA6
Criteria criteria = iKJ-$x_5
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detachedCriteria.getExecutableCriteria(session); WH>= *\
return criteria.list(); (Dy6I;S
} >@b]t,rrK
}, true); R`[jkJrc
} B]KR *
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public int getCountByCriteria(final ?Uq;>
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DetachedCriteria detachedCriteria){ ^tMb"WO
Integer count = (Integer) \dm5Em/
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getHibernateTemplate().execute(new HibernateCallback(){ B0h|Y.S8%1
publicObject doInHibernate R[C+?qux
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(Session session)throws HibernateException { q7}r D$
Criteria criteria = q 9e(YX>
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detachedCriteria.getExecutableCriteria(session); Uuxx^>"h\
return VjI=5)+~
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criteria.setProjection(Projections.rowCount N)I9NM[
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()).uniqueResult(); M_I.Y1|
} Bi.,@7|>
}, true); j8cIpbp8x
return count.intValue(); Y3_C':r
} %Z8'h\|
} w#XD4kwQG
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用户在web层构造查询条件detachedCriteria,和可选的 uPT2ga ]
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 `!udU,|N
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PaginationSupport的实例ps。 lZ'WFFWLE
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ps.getItems()得到已分页好的结果集 DruiiA
ps.getIndexes()得到分页索引的数组 kF;N}O2?{
ps.getTotalCount()得到总结果数 oimM)Yo
ps.getStartIndex()当前分页索引 F@tfbDO?
ps.getNextIndex()下一页索引 _xefFy
ps.getPreviousIndex()上一页索引 O
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 0!Vza?9
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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 ~n"?*I`
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一下代码重构了。 Ke;eI+P[
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我把原本我的做法也提供出来供大家讨论吧: ,M.phRJ-`
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首先,为了实现分页查询,我封装了一个Page类: K1+4W=|
java代码: )ZW[$:wA
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/*Created on 2005-4-14*/ ;*G';VuT
package org.flyware.util.page; ;/h&40&
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/** '8yC wk
* @author Joa j S4\;
* !X[P)/?b0+
*/ ,Y4>$:#n/
publicclass Page { UhKd o
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/** imply if the page has previous page */ q'Nafa&a)
privateboolean hasPrePage; E!9(6G4
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/** imply if the page has next page */ ~n~j2OE
privateboolean hasNextPage; n *EGOS
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/** the number of every page */ [v+5|twxpU
privateint everyPage; iG ,z3/~v
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/** the total page number */ 6U0BP
privateint totalPage; -q]5@s/
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/** the number of current page */ 1I awi?73
privateint currentPage; cy(4g-b]@e
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/** the begin index of the records by the current &qzy?/i8
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query */ @#p6C
privateint beginIndex; #tIeI6Qw
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/** The default constructor */ MtVvi6T
public Page(){ /^L<q
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} vqAEF^HYry
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/** construct the page by everyPage rb*0YCi
* @param everyPage wmA TV/
* */ jLA)Y
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public Page(int everyPage){ y=aWSb2y'
this.everyPage = everyPage; e*yl _iW
} ["#H/L]3
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/** The whole constructor */ [1Aoj|
public Page(boolean hasPrePage, boolean hasNextPage, I+F>^4_d
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int everyPage, int totalPage, !9{hbmF#
int currentPage, int beginIndex){ )MF 4b][
this.hasPrePage = hasPrePage; :-WNw
n
this.hasNextPage = hasNextPage; 2q(gWhcj
this.everyPage = everyPage; 44s 9\
this.totalPage = totalPage; W'~s
this.currentPage = currentPage; D59q/@
this.beginIndex = beginIndex; UpPl-jeT
} ZWni5uF-c
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/** h;#046-7
* @return 5UJ ?1"J
* Returns the beginIndex. zBK"k]rz
*/ }Q*J!OH
publicint getBeginIndex(){
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return beginIndex; tZv^uuEp3
} !Eg2#a ?
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/** !C|Z+w9Y
* @param beginIndex { P,hH~!
* The beginIndex to set. %gQUog
*/ V'gJtF
publicvoid setBeginIndex(int beginIndex){ lQiw8qD
this.beginIndex = beginIndex; bIlNA )g
} &uF~t
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/** Y<jX[ET!
* @return =''WA:,=h
* Returns the currentPage. Ir-QD!!<
*/ XdmpfUR,13
publicint getCurrentPage(){ P*B@it
return currentPage; a~J!G:(
} 5}Id[%.x
;5.<M<PH
/** ?PS?_+E\L
* @param currentPage LEOri=?RF
* The currentPage to set. T*gG <8
*/ %t$KVV
publicvoid setCurrentPage(int currentPage){ 71>,tq
this.currentPage = currentPage; tSux5yV
} ]l C2YD}
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/** xY/F)JOeG
* @return :iLRCK3C
* Returns the everyPage. *];QPi~
*/ ,(Ol]W}
publicint getEveryPage(){ ^pH8'^n
return everyPage; /qJC p![X
} oc]:Ty
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/** H3*]}=
* @param everyPage V?'p E
* The everyPage to set. \<(EV,m2
*/ n$XEazUb0N
publicvoid setEveryPage(int everyPage){ :4-,Ru1C"
this.everyPage = everyPage; +Adk1N8
} ,*dLE
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/** \q*-9_M
* @return 3[y$$qXI
* Returns the hasNextPage. jl>TZ)4}V
*/ Qu,R6G
publicboolean getHasNextPage(){ maDWV&Db
return hasNextPage; %gs?~Xl)]
} Ww60-d}}Q
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/** DQ3L=
* @param hasNextPage `"[qb ?z
* The hasNextPage to set. ,`RX~ H=C
*/ n?$c"}
publicvoid setHasNextPage(boolean hasNextPage){ =Gu&0f
this.hasNextPage = hasNextPage; u8.Tu7~
} .)$MZyo
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/** EPH
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* @return T*SLM"x
* Returns the hasPrePage. 54Rp0otv
*/ |&{S ~^$
publicboolean getHasPrePage(){ =R'O5J
return hasPrePage; n42\ty9
} _tX=xAO9
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/** AEaN7[PQx|
* @param hasPrePage |nWEuKHy
* The hasPrePage to set. 8C8S)
;
*/ P`{$7ST'Hh
publicvoid setHasPrePage(boolean hasPrePage){ :H3/+/x
this.hasPrePage = hasPrePage; $/C1s"C@O
} q`/J2r+O
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/** ~tt\^:\3~S
* @return Returns the totalPage. .4R.$`z4
* lya},_WCq
*/ Q&vdBO/
publicint getTotalPage(){ ~G@YA8}
return totalPage; ha$1vi}b
} tB"9%4](
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/** 2b"DkJj'
* @param totalPage ,8Po
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* The totalPage to set. .l_Nf9=
*/ p*,T~(A6
publicvoid setTotalPage(int totalPage){ ssx#|InY
this.totalPage = totalPage; 3: WEODV2
} wpYk`Lr
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}
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 |@'O3KA
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个PageUtil,负责对Page对象进行构造: cZ?$_;=
java代码: ~`QoBZ.O&
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/*Created on 2005-4-14*/ 3~tu\TH6d
package org.flyware.util.page; P'OvwA
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import org.apache.commons.logging.Log; 96<oX:#
import org.apache.commons.logging.LogFactory; t!3N|`x
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/** lTqlQ<`V
* @author Joa D)ri_w!Q
* U< Xdhgo?
*/ [Cv./hEQi
publicclass PageUtil { uOLShNo
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privatestaticfinal Log logger = LogFactory.getLog N4C7I1ihq
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(PageUtil.class); a24 AmoWx
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/** .7^(~&5N
* Use the origin page to create a new page ]<f(@]R/d
* @param page C$6FI`J
* @param totalRecords <A)M^,#o
* @return *PnO$q@`
*/ B F<u3p??
publicstatic Page createPage(Page page, int `"&Nw,C
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totalRecords){ WM
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return createPage(page.getEveryPage(), Pn OWQ8=
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page.getCurrentPage(), totalRecords); {owuYVm
} K-C,n~-
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/** {IV%_y?
* the basic page utils not including exception \6&Ml]1
`9K5 ;]
handler h9ScN(|0y
* @param everyPage ":Tm6Nj
* @param currentPage Yw3'9m^
* @param totalRecords )ciP6WzzbI
* @return page W]ca~%r
*/ g) u%?T
publicstatic Page createPage(int everyPage, int E^F<"mL*
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currentPage, int totalRecords){ ~SQxFAto
everyPage = getEveryPage(everyPage); @h{|tP%"
currentPage = getCurrentPage(currentPage); w7?fJ")
int beginIndex = getBeginIndex(everyPage, $C\ETQ@
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currentPage); pVy=rS-
int totalPage = getTotalPage(everyPage, 0wv#AT
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totalRecords); mg'q-G`\<
boolean hasNextPage = hasNextPage(currentPage, ~%/Rc`
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totalPage); .
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boolean hasPrePage = hasPrePage(currentPage); B]"`}jn
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returnnew Page(hasPrePage, hasNextPage, `sCaGCp
everyPage, totalPage, ,-y9P
currentPage, XJ4f;U
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beginIndex); H/O.h@E4X
} 8~o']B;lJ
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privatestaticint getEveryPage(int everyPage){ C.92FiC
return everyPage == 0 ? 10 : everyPage; !lgL=Ys(
} aDNB~CwZZ
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privatestaticint getCurrentPage(int currentPage){ uPz+*4+
return currentPage == 0 ? 1 : currentPage; ;9T}h2^`B
} %f1%9YH
h$l/wn
privatestaticint getBeginIndex(int everyPage, int }%jF!d
R#d~a;j
currentPage){ V|MGG
return(currentPage - 1) * everyPage; ={:a
N)
} .Ix3wR9
X=$Jp.
privatestaticint getTotalPage(int everyPage, int :*''ci
(G"'Fb6d
totalRecords){ Q4"\k.
?
int totalPage = 0; n(F!t,S1i
P9cx&Hk9
if(totalRecords % everyPage == 0) 2^WJ1: A
totalPage = totalRecords / everyPage; d+JK")$9C
else l'+3
6
totalPage = totalRecords / everyPage + 1 ; 'cs(gc0
j?.F-ar
return totalPage; F<* / J]
} QO'Hyf t
:X;G]B
.
privatestaticboolean hasPrePage(int currentPage){ Kq")\Ha,f
return currentPage == 1 ? false : true; !wy _3a
} i<Vc~!pT
m@2E ~m
privatestaticboolean hasNextPage(int currentPage, \cIN]=#
b&z#ZY
int totalPage){ lYx_8x2
return currentPage == totalPage || totalPage == Zo3!Hs ZA
a$My6Qa#
0 ? false : true; bBjr hi
} A>@#eyB
]ZY2\'
9jkz83/+<
} %v0M~J}+
QJ2]8K)+C
i
9)
Gt
v/`D0g-uX)
(u,)v_Oo]a
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。 c?A$Y?|9
v"bWVc~H
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 3Zb%-_%j
@Po5AK3cy
做法如下: iE~!?N|a3
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 }@r23g%
DB' 0
的信息,和一个结果集List: E`IXBI
java代码: KUI{Z I
cbzA`b'Mg
t%=7v)IOE
/*Created on 2005-6-13*/ nh} Xu~#_
package com.adt.bo; INg0[Lpc
`fBQ?[05.
import java.util.List; 5PeS/%uT@
;,4*uU'vq
import org.flyware.util.page.Page; fzSkl`K}
/7AHd ;
/** MpCPY"WLL
* @author Joa nQF&^1n
*/ Qd}n4KF\
publicclass Result { @Kpm&vd(
NdXHpq;
private Page page; c+:ZmrP/
#dauXUKH
private List content; Y+?QHtZL
Q"QRF5Ue
/** E2e"A
I.h
* The default constructor F]$ Nu
*/ 37U8<
public Result(){ Ni_H1G
super(); @ st>#]i4
} [?]N
GTr#
y~9wxK
/** O<m46mwM
* The constructor using fields @kYY1m v;
* _jQ:9,;
A
* @param page 8em'7hR9
* @param content 7)rQf{q7
*/ |L<JOQ
public Result(Page page, List content){
|Xso}Y{
this.page = page; QiPqN$n
this.content = content; _}l(i1o,/
} |+cz\+
t~+M>Fjm?d
/** <y6`8J7:
* @return Returns the content. PQHztS"
*/ -)V0D,r$[
publicList getContent(){ ,1-%C)
return content; Y+-yIMt$r
} o|xf2k
S^QEc tXU
/** q\fbrv%I4
* @return Returns the page. !sT>]e
*/
NFT:$>83`
public Page getPage(){ )UR$VL
return page; r:QLU]
} ;z:Rj}l
v{" nyW6#
/** uo:RNokjJ
* @param content E?w#$HS
* The content to set. &CG94
*/ mv9D{_,pD
public void setContent(List content){ -)A:@+GF
this.content = content; t^#1=nK
} )vtbA=RH?
i~!g9o(
/** yFE0a"0y
* @param page Gs:g
* The page to set. 1 iH@vd
*/
']}-;m\
publicvoid setPage(Page page){ #qd!_oN
this.page = page; Jz8P':6[
} _H| )g*]t
} (Jq m9
5_^d3LOT0x
i\xs!QU
hb[ThQ
?$pNd uE
2. 编写业务逻辑接口,并实现它(UserManager, @nH3nn
w-).HPe
UserManagerImpl) jFQ y[k-B
java代码: !'$*Z(
frcAXh9
bJ2-lU% ;2
/*Created on 2005-7-15*/ ]OpGD5jZ
package com.adt.service; cW3'057
wSR|uh
import net.sf.hibernate.HibernateException; 49FP&NgK
XDK Me}
import org.flyware.util.page.Page; _`2%)#^o
'(K4@[3t
import com.adt.bo.Result; dsIbr"m
eF3NyL(A
/** ?V`-z#y7
* @author Joa 3W'fEh5
*/ ;MfqI/B{
publicinterface UserManager { Y{dSQ|xz^
uQdeKp4(
public Result listUser(Page page)throws f1NHW|_j
wBt7S!>G
HibernateException; rfDGS%!O%
e N`+ r
} CI*JedO]
0Gu77&
A
rE~6X
EW$drY@
Uz ;^R@
java代码: Q<>u)%92@
TG=A]--_a
9Qyc!s`
/*Created on 2005-7-15*/ N[@~q~v
package com.adt.service.impl; *)[fGxz
\
bUgg2iFS
import java.util.List; w5Fk#zJv
/`cy4<
import net.sf.hibernate.HibernateException; QMMpB{FZ`o
qkfof{z
import org.flyware.util.page.Page; smCACQ$(
import org.flyware.util.page.PageUtil; 8wWp+Hk
#19O5
import com.adt.bo.Result; mxqZj8VuH
import com.adt.dao.UserDAO; Gza=
0
import com.adt.exception.ObjectNotFoundException;
R &1>\t
import com.adt.service.UserManager; IB|!51H
kR+}7G+
/** !>(uhuTBF
* @author Joa :V(C+bm *
*/ .BxI~d^
publicclass UserManagerImpl implements UserManager { <.`i,|?MHS
9@1n:X
private UserDAO userDAO; J_F\cM
E+y_te^+b
/** p;4FZ$
* @param userDAO The userDAO to set. |X{j^JP5
*/ C.4(8~Y=~
publicvoid setUserDAO(UserDAO userDAO){ 6$#,$a O
this.userDAO = userDAO; Kmx4bp4
} 5kqI
G5hRx@vfrL
/* (non-Javadoc) `K VSYC
* @see com.adt.service.UserManager#listUser 39^+;Mev
)EMlGM'2q
(org.flyware.util.page.Page) 5CnNp?.t^
*/ `U0XvWPr[
public Result listUser(Page page)throws /'oo;e
9ad`q+kY
HibernateException, ObjectNotFoundException { xkf2;
int totalRecords = userDAO.getUserCount(); f)vnm*&-
if(totalRecords == 0) xS,F
DPA
throw new ObjectNotFoundException #Q2s3"X[
.LAB8bg
("userNotExist"); i:Y5aZc/Ds
page = PageUtil.createPage(page, totalRecords); t7-r YY(
List users = userDAO.getUserByPage(page); ~_BjcY
returnnew Result(page, users); ?uCL[
} 3]S_w[Q4
/ 8O=3
} R?{_Q<17
OGEe8Z9Jt
m
+A4aQ9
)E9c6'd
O<fy^[r:`
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ]9_tto!/
1.%|Er 4
询,接下来编写UserDAO的代码: ]U@~vA#''
3. UserDAO 和 UserDAOImpl: jhRr!
java代码: _G)A$6weU
;Q3[} ]su
62;xK-U
/*Created on 2005-7-15*/ nK< v
package com.adt.dao; (e_<~+E
= ~s+<9c]
import java.util.List; _an0G?7
q4X(_t
import org.flyware.util.page.Page; BN&)5M?Xt6
nh7_
jEX
import net.sf.hibernate.HibernateException; UvMkL
_zbIS&4
/** ,J 2qLH1
* @author Joa NPv.7,
*/ w\[l4|g`
publicinterface UserDAO extends BaseDAO { ,e|"p[z~T
7oZ Pb
publicList getUserByName(String name)throws z\FBN=54z
4'3;{k$z
HibernateException; 0"j:-1
^$dbyj`
publicint getUserCount()throws HibernateException; ElTB{C>u
7Wv.-LD6
publicList getUserByPage(Page page)throws 0NSw^dO\
?@in($67
HibernateException; Z@Q/P(t
He8]Eb
} d<Lc&wlP
f5M;q;
YXTV$A+lW
+<$nZ=,hsy
S/*\j7cj
java代码: @gqZiFM)
W4.w
NsS;d^%I
/*Created on 2005-7-15*/ h}nS&.
package com.adt.dao.impl; {tOf0W|
Px-VRANZt
import java.util.List; 34CcZEQQ
7f3,czW
import org.flyware.util.page.Page; 4n.JRR&;
Kt qOA[6
import net.sf.hibernate.HibernateException; ;t9!<L
import net.sf.hibernate.Query; UM0Ws|qx&
0N)DHD?U
import com.adt.dao.UserDAO; T_s09Wl
\^pc"?Rc
/** &2%|?f|
* @author Joa Mb"y{Fox
*/ k8J zey]X
public class UserDAOImpl extends BaseDAOHibernateImpl oM>UIDCY_v
AMB{Fssz
implements UserDAO { tz?3R#rM
4V{&[ Z
/* (non-Javadoc) G*_]Lz(N
* @see com.adt.dao.UserDAO#getUserByName FS)#
v
>jiez,
(java.lang.String) r"K!]Vw
*/ O..{wdZy
publicList getUserByName(String name)throws ^AI02`c.
2::YR?
HibernateException { kWa5=BW2f
String querySentence = "FROM user in class ,K@[+ R!
LRWM}'.s
com.adt.po.User WHERE user.name=:name"; [X /s^42
Query query = getSession().createQuery z3 ^_C`(F
'aV'Am+:
(querySentence); -B/'ArOo]
query.setParameter("name", name); ^kC!a>&
return query.list(); .>r3ZwrE'
} V=&M\58
_U LzA
/* (non-Javadoc) R#YeE`K
* @see com.adt.dao.UserDAO#getUserCount() 9D`K#3}
*/ x'?p?u~[
publicint getUserCount()throws HibernateException { wjH1Ombt
int count = 0; fUCjC*#1
String querySentence = "SELECT count(*) FROM S8kzAT
$"(
15U
user in class com.adt.po.User"; 0=U|7%dOL
Query query = getSession().createQuery A4rMJ+!5
%A3m%&(m&%
(querySentence); WB_BEh[>j
count = ((Integer)query.iterate().next x8C\&ivn
LibQlNW\
()).intValue(); IS!OO<
return count; (x\VGo
} I0H]s/*C%9
qAd=i0{N
/* (non-Javadoc) 6&;GC<].(y
* @see com.adt.dao.UserDAO#getUserByPage 5|r*,!CF
21Dc.t{
(org.flyware.util.page.Page) "l-#v|
54
*/ WcT= 5G
publicList getUserByPage(Page page)throws u23_*W\
x'\C'zeF
HibernateException { g yV>k=B
String querySentence = "FROM user in class 'wYIJK~1
/TPtPq<7:#
com.adt.po.User"; N.q*jY=X|
Query query = getSession().createQuery k18v{)i~
!&b|
[b
(querySentence); p/nATvh$
query.setFirstResult(page.getBeginIndex()) o
o'7
.setMaxResults(page.getEveryPage()); |/xx**?
return query.list(); uh.;Jj;
} U/AiI;Ne
\\13n4fAv
} DrioBb@
G9Kck|50
uxDM
#
A/:_uqm4
EAXl.Y.
$
至此,一个完整的分页程序完成。前台的只需要调用 ZCZ@ZN
^Lc\{,m
userManager.listUser(page)即可得到一个Page对象和结果集对象 _[E+D0A
1|w@f&W"
的综合体,而传入的参数page对象则可以由前台传入,如果用 k]$oir
P%Vq#5
webwork,甚至可以直接在配置文件中指定。 =+mb@#="m
uJH[C>
下面给出一个webwork调用示例: \X\f~CB
java代码: |
?vm.zp
eC%Skw
Cy/VH"G=
/*Created on 2005-6-17*/ eCsk\f`
package com.adt.action.user; U+>M@!=
A-uIZ
zC
import java.util.List; LWTPNp:"{w
z7AWWr=H
import org.apache.commons.logging.Log; flC%<V%'-
import org.apache.commons.logging.LogFactory; =&pLlG
import org.flyware.util.page.Page; 6hd<ys?
3+uL@LXd
import com.adt.bo.Result; *-Yw%uR
import com.adt.service.UserService; T_D] rMl
import com.opensymphony.xwork.Action; .1;UEb|T
;>5`Y8s6
/**
LFW`ISY{
* @author Joa N%Ta.`r
*/ %c\kLSe
publicclass ListUser implementsAction{ _h#I}uJ~
gELG/6l
privatestaticfinal Log logger = LogFactory.getLog `?N0?;
AnX<\7bc}
(ListUser.class); ZfqN4
6MY<6t0a
private UserService userService; 'n-y*f
UQ0<sI=
private Page page; 7XyCl&Dc:
#6ePwd
privateList users; _ pz}
DZC@^k \E
/* wxc#)W
* (non-Javadoc) I-r+1gty
* wz69Yw7
* @see com.opensymphony.xwork.Action#execute() |]@Pq[Hn|
*/ 3Y2~HuM
publicString execute()throwsException{ <C(o0u&/
Result result = userService.listUser(page); egG<"e*W}N
page = result.getPage(); :yD>Tn;1
users = result.getContent(); HLwMo&*rA
return SUCCESS; r#4/~a5i~
} ML\>TDt
kO3\v)B;
/** Pb8@owG8
* @return Returns the page. C[
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*/ KsOWTq"uj
public Page getPage(){
JL1A3G
return page; 1,;X4/*
} p+V#86(3
J,CwC)
/** <OGG(dI
* @return Returns the users. 9)'f)60^
*/ lh"*$.j-
publicList getUsers(){ c'eZ-\d{
return users; ]n|Jc_Y
} m:?"|.]
(XVBH1p"
/** \/Mx|7<
* @param page ,oA<xP-*
* The page to set. esnq/
*/ 6ABK)m-y
publicvoid setPage(Page page){ :+PE1=v
this.page = page; ={ms@/e/T
} (n*:LS=0
p8!T)
?|
/** A'KH_])
* @param users [rT.k5_
* The users to set. [|KvlOvP
*/ ?PT>V,&
publicvoid setUsers(List users){ v wEbGx
this.users = users; nlNk
}
qt~=47<d
~.%HZzR6&
/** <ErX<(0`ig
* @param userService )|lxzlk
* The userService to set. pqfX}x
*/ R^*baiXVI
publicvoid setUserService(UserService userService){
zd=O;T;.
this.userService = userService; ?qaWt/m
} >SK:b/i
} ]h,rgO;
L\PmT
c lB K
Q-
| Y
s;Gd`-S>d
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, k9;^|Cm
k
c;$4}U4
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 aZWj52
cQK-Euum
么只需要: _VKI@
java代码: *i]?J
(jc& Fk
IA@>'O
<?xml version="1.0"?> (h3L=
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork m$W>~
E&P2E3P
1.0//EN" "http://www.opensymphony.com/xwork/xwork- C_Ewu*T7
'k X8}bx
1.0.dtd"> H&)}Z6C"
+P2oQ_Fk`9
<xwork> !5o j~H
e|\xFV=4
<package name="user" extends="webwork- gA!@oiq@
Wb-C0^dTn
interceptors"> pd|KIs%jl
y QW7ng7D0
<!-- The default interceptor stack name \l~^dn}
zsg\|=P
--> @KQ.t F*
<default-interceptor-ref gJ
\6cZD
SMX]JZmH
name="myDefaultWebStack"/> N,Eap KG
mn/)_1',
<action name="listUser" +i&<`ov
Q 7_5
class="com.adt.action.user.ListUser"> 3f[Yk#"
<param 6c-/D.M
aOwjYl[?p
name="page.everyPage">10</param> <.6rl
<result JLoF!MK}
%f;dn<m=c
name="success">/user/user_list.jsp</result> E~%n-A
</action> h1w({<q*ov
l6/VJ~(}'
</package> kFn/dQ4|
m4mE7Wn.3
</xwork> O[Vet/^)
MuoE~K2
<\^0!v
QqA=QTZ}
v'W{+>.
l P F326e
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 i2,4:M)CV
1RRE{]2v#
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。 Y![Q1D!
X Q#K1Z
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 s#9q3JV0
4S<M9A}
v675C# l(
?QOU9"@+B
`q?3ux
我写的一个用于分页的类,用了泛型了,hoho b@Ej$t&
UM oj9/-
java代码: }L\;W:0
&k:xr,N=
oD)]4|
package com.intokr.util; !g@Ky$
u m9yO'[C
import java.util.List; 'Gy`e-yB
_U s"
/** F]\
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* 用于分页的类<br> t'n@yX_
* 可以用于传递查询的结果也可以用于传送查询的参数<br> lPy|>&Yc
* V8^la'_j
* @version 0.01 ~:ASv>m
* @author cheng >JpBX+]5m
*/ im<bo Mv
public class Paginator<E> { v:t;Uk^Y
privateint count = 0; // 总记录数 l0qaTpn
privateint p = 1; // 页编号 1Bj.MQ^
privateint num = 20; // 每页的记录数
/8x';hQ
privateList<E> results = null; // 结果 azP H~'E'
{^N,=m\
/** u8Ys2KLpL
* 结果总数 2n<Mu Q]
*/ Qs&;MW4q
publicint getCount(){ G4*
LO
return count; m\&|#yq
} a-{|/
n%
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publicvoid setCount(int count){ {VcRur}&Y8
this.count = count; =zkN63S
} n'~==2
7he73
/** 1m*)MZ)
* 本结果所在的页码,从1开始 EA"hie7
* W$4$%r8
* @return Returns the pageNo. Coi[cfg0
*/ 0<,{poMM
publicint getP(){ mTZ/C#ir(
return p; 6TP
/0o)
} O$ *lPA[
h^Wb<O`S
/** zI`I
Q
* if(p<=0) p=1 %*R, ceuI
* EF0v!XW
* @param p giakEPl
*/ YYWD\Y`8
publicvoid setP(int p){ k@4N7}
if(p <= 0) }y(t')= 9
p = 1; IW~R{ ]6
this.p = p; TM)INo^
} 6/UOzV,[
`Fd
\dn
/** gRLt0&Q~
* 每页记录数量 qM\
2f<)
*/
^^a6 (b
publicint getNum(){ uNyU]@R<W
return num; ~y<0Cc3Vs
} thjr1y.e
Z)@vJZ*7(
/** 'RjEdLrI
* if(num<1) num=1 Lq(=0U\"P
*/ wvv+~K9jq
publicvoid setNum(int num){ Z"`w>c.
if(num < 1) )lG}B U.
num = 1; UG2+Y']
this.num = num; Z/Rp?Jz\j/
} DbMVbgz<e
V]H(;+^P
/** .?Eb{W)^br
* 获得总页数 )z[C=
*/ ,^/Wv!uPE
publicint getPageNum(){ ]Lv P)0=
return(count - 1) / num + 1; S\GWMB!oF
} 8E%LhA.
#(^<qr
/** |AYii-g
* 获得本页的开始编号,为 (p-1)*num+1 cYSn
*/ =H{<}>W'
publicint getStart(){ 7`|'Om?'
return(p - 1) * num + 1; "N+4TfXy
} s)-An(Uw
{ DYY9MG8
/** S?688
* @return Returns the results. 5CI{&E
*/ h FU8iB`Q
publicList<E> getResults(){ }-3 VK%
return results; X=QX9Ux?^
} #Vk?
"laf:Ty1
public void setResults(List<E> results){ *AH`ob}
this.results = results; 4|x_C-@
} *zdD4I=
4C;;V m4~
public String toString(){ Fb,*;M1'
StringBuilder buff = new StringBuilder #}7T$Va
HPtMp#`T
(); W@R7CQE@
buff.append("{"); Rw+r1vW:A
buff.append("count:").append(count); )tlj{ 7p
buff.append(",p:").append(p); iv*RE9?^
buff.append(",nump:").append(num); pwo$qs(p
buff.append(",results:").append ZF7n]LgSc&
g QBS#NY
(results); T+Yv5l
buff.append("}"); x^lcT
return buff.toString(); )1At/ mr
} a6Vfd&
a*p|Ij
} 13?:a[~=Y
*7AB0y0k
Ii0\Skb