Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 h7UNmwj
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 _o$jk8jOjW
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 kygw}|, N
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改
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。 <]M.K3>
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分页支持类: `Zm6e!dH-
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java代码: 4?'vP '
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package com.javaeye.common.util; 1*TbgxS~W
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import java.util.List; YOD.y!.zq7
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publicclass PaginationSupport { 0
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publicfinalstaticint PAGESIZE = 30; "0P`=n
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privateint pageSize = PAGESIZE; ukW&\
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privateList items; ;=ddv@
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privateint totalCount; s{Z)<n03
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privateint[] indexes = newint[0]; e"nm< &
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privateint startIndex = 0; CJ
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public PaginationSupport(List items, int z~
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totalCount){ Wh)D_
setPageSize(PAGESIZE); ai{>rO3 }I
setTotalCount(totalCount); { qNPhi
setItems(items); A9$x8x*Lt
setStartIndex(0); %=`JWLLG
} Lnr9*dm6q
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public PaginationSupport(List items, int ^`&'u_B!+
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totalCount, int startIndex){ g'(bk@<BP
setPageSize(PAGESIZE); ANM#Kx+
setTotalCount(totalCount); pH1!6X
setItems(items); *GT=U(d
setStartIndex(startIndex); #Iw(+%D
} b(Nv`'O
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public PaginationSupport(List items, int 4b8G 1fm
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totalCount, int pageSize, int startIndex){ p)y5[HX
setPageSize(pageSize); v ,8;:
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setTotalCount(totalCount); vrnvv?HPrR
setItems(items); Hr|f(9xA
setStartIndex(startIndex); oP&/>GmXL
} ?b
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publicList getItems(){ Bm$|XS3cD
return items; ^4dE8Ve"@
} cb}"giXQTB
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publicvoid setItems(List items){ z*\_+u~u
this.items = items; QL?_FwZL
} De?VZ2o9"
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publicint getPageSize(){ i}-uK,^
return pageSize; i?x gV_q;
} rq+_[!
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publicvoid setPageSize(int pageSize){ n5:uG'L\
this.pageSize = pageSize; cS ~OxAS
} M<vPE4TIr*
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publicint getTotalCount(){ ` 2lS@
return totalCount; +jm,nM9
} 0U '"@A
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publicvoid setTotalCount(int totalCount){ 1[FN: hm
if(totalCount > 0){ ]G/m,Zv*:
this.totalCount = totalCount; ,;k+n)
int count = totalCount / ci0A!wWD
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pageSize; W }NUU
if(totalCount % pageSize > 0) c_J9CKqc
count++; @\K[WqF$$q
indexes = newint[count]; "Xq_N4
for(int i = 0; i < count; i++){ dWAt#xII
indexes = pageSize * @X==[gQ
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} <kh.fu@.Q
}else{ p~D}Iyww1_
this.totalCount = 0; ,06Sm]4L,
} Rh>B#
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} amBg<P`'_
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publicint[] getIndexes(){ d"wA"*8~y
return indexes; ?nU<cx h
} ]aX@(3G1s
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publicvoid setIndexes(int[] indexes){ $8tk|uh
this.indexes = indexes; K~W(ZmB
} 9YzV48su#
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publicint getStartIndex(){ zakhJ
return startIndex; 2]!@)fio`
} fBS a8D3}`
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publicvoid setStartIndex(int startIndex){ 7;>|9k
if(totalCount <= 0) lC<;Q*Y
this.startIndex = 0; DiJLWXs
elseif(startIndex >= totalCount) fG0 ?"x@>
this.startIndex = indexes GZ%vFje_
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[indexes.length - 1]; !KHgHKEW^
elseif(startIndex < 0) ;ALWL~Xm
this.startIndex = 0; \}Q=q$)
else{ 09kR2(nsW/
this.startIndex = indexes AuNUW0/
7
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[startIndex / pageSize]; q*I*B1p[m
} *`>BOl+ro
} @16GF!.
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publicint getNextIndex(){ <PLAAh8
int nextIndex = getStartIndex() + B[b>T=
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pageSize; !%>RHh[
if(nextIndex >= totalCount) @MSmg3&
return getStartIndex(); s.J4&2Q
else F!+1w(b:
return nextIndex; R%UTYRLUn
} ,i:?c
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publicint getPreviousIndex(){ +B*]RL[th
int previousIndex = getStartIndex() - 7l *
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pageSize; ,s8/6n#
if(previousIndex < 0) nI:M!j5s`
return0; <)7aNW.
else us.#|~i<h
return previousIndex; :[0 R F^2}
} tZ_'>7)
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} ';C'9k<P:
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抽象业务类 PaCCUF
java代码: |ADf~-AY
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/** P:{Aqn~zR
* Created on 2005-7-12 c
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*/ VYG@_fd!x
package com.javaeye.common.business; A
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import java.io.Serializable; }UPC~kC+Z
import java.util.List; Xm#W}Y'
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import org.hibernate.Criteria; #/oH #/?
import org.hibernate.HibernateException; %o?)`z9-
import org.hibernate.Session;
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import org.hibernate.criterion.DetachedCriteria; _dKMBcl)E
import org.hibernate.criterion.Projections; ~1O|4mssS
import eoiz]L
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org.springframework.orm.hibernate3.HibernateCallback; ]IV{;{E)
import V0;"Qa@q
}#ink4dK:
org.springframework.orm.hibernate3.support.HibernateDaoS $Cz2b/O
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upport; $_S-R
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import com.javaeye.common.util.PaginationSupport; 5]&sXs
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public abstract class AbstractManager extends gX"-3w
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HibernateDaoSupport { aM~IRLmK
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privateboolean cacheQueries = false; 8?Rp2n*o
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privateString queryCacheRegion; L-9fo-
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publicvoid setCacheQueries(boolean Z@s[8wrmPl
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cacheQueries){ qSP&Fi
this.cacheQueries = cacheQueries; d5^^h<'
} p8'$@:M\
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publicvoid setQueryCacheRegion(String -))S
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queryCacheRegion){ -Cyo2wk
this.queryCacheRegion = 35l%iaj]G5
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queryCacheRegion; ].Yz
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} 5Npxs&Ea
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publicvoid save(finalObject entity){ SnG(/1C8
getHibernateTemplate().save(entity); T +vo)9w
} ~61b^L}$
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publicvoid persist(finalObject entity){ ].s;Yxz
getHibernateTemplate().save(entity); x3i}IC
} 6 J>A U
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publicvoid update(finalObject entity){ Qs\a&Q=0H
getHibernateTemplate().update(entity); =803rNe
} D% j GK
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publicvoid delete(finalObject entity){ 3RaW\cWzg
getHibernateTemplate().delete(entity); +(2$YJ35
} Q0(6n8i
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publicObject load(finalClass entity, %W~w\mT
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finalSerializable id){ >e {1e
return getHibernateTemplate().load Z5Lmg
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(entity, id); 9)7$U QY
} 2VRGTx
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publicObject get(finalClass entity, t8-P'3,Q$
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finalSerializable id){ U>lf-iI2B
return getHibernateTemplate().get F
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(entity, id); ]JkEf?;.
} o6vnl
}. &ellNQ
publicList findAll(finalClass entity){ y.lWyH9
return getHibernateTemplate().find("from 41<~_+-@
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" + entity.getName()); #DgHF*GG+>
} -Fd&rq:GB(
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publicList findByNamedQuery(finalString Ms|c"?se
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namedQuery){ AY5iTbL1
return getHibernateTemplate T)gulP
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().findByNamedQuery(namedQuery);
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} #B5,k|"/,M
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publicList findByNamedQuery(finalString query, !Q[v"6?
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finalObject parameter){ 74M 9z
return getHibernateTemplate {]+t<
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().findByNamedQuery(query, parameter); jn5xYKv
} i#V(oSx
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publicList findByNamedQuery(finalString query, QP%_2m>yhl
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finalObject[] parameters){ nq{/fD(2
return getHibernateTemplate i"G'#n~e
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().findByNamedQuery(query, parameters); es*$/A
} \o!3TK"N
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publicList find(finalString query){ mU-2s%X<.^
return getHibernateTemplate().find -!XG>Z
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(query); [1vm~w'
} _uO$=4Sd
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publicList find(finalString query, finalObject `2 <:$]
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parameter){ Y2DL%'K^
return getHibernateTemplate().find _BP%@o
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(query, parameter); 8@rYT5e3c
} (C.
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public PaginationSupport findPageByCriteria Gk~aTO
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(final DetachedCriteria detachedCriteria){ /f[Ek5/-0
return findPageByCriteria XN<!.RCw
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); G^ GIHdo
} %f'pAc|#
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public PaginationSupport findPageByCriteria futYMoV
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(final DetachedCriteria detachedCriteria, finalint Sl8+A+
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startIndex){ Yd3lL:M
return findPageByCriteria -
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(detachedCriteria, PaginationSupport.PAGESIZE, 3g;Y
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startIndex); =wX;OK|U(^
} J6CSu7Voa
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public PaginationSupport findPageByCriteria C?|sQcCE
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(final DetachedCriteria detachedCriteria, finalint sR/Yv
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pageSize, ~a_hOKU5
finalint startIndex){ 6{5T^^x?<
return(PaginationSupport) _qE9]mU
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getHibernateTemplate().execute(new HibernateCallback(){ IrZjlnht
publicObject doInHibernate 1#N`elm
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(Session session)throws HibernateException { @2"uJ6o
Criteria criteria = P.>fkO1\
h.?<(I
detachedCriteria.getExecutableCriteria(session); K-]) RIM
int totalCount = )$p36dWl
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((Integer) criteria.setProjection(Projections.rowCount dXDyY
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()).uniqueResult()).intValue(); ,$!fyi[;C
criteria.setProjection $|7"9W}m*
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(null); z2V ->UK)
List items = :Jyr^0`J
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criteria.setFirstResult(startIndex).setMaxResults ]iTP5~8U
lFuW8G,-f@
(pageSize).list(); JQ
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PaginationSupport ps = 6DHZ,gWq
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new PaginationSupport(items, totalCount, pageSize, ~Q"qz<WO
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startIndex); ,r3`u2)
return ps; W/RB|TMT
} Gmu[UI}w8
}, true); 1WaQWZ:=
} |9i[*]
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public List findAllByCriteria(final :
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}`Wo(E}O
DetachedCriteria detachedCriteria){ .`KzA]
return(List) getHibernateTemplate 7&etnQJ{
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().execute(new HibernateCallback(){ ?pQ0*
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publicObject doInHibernate DIYR8l}x
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(Session session)throws HibernateException { ]/p>p3@1C
Criteria criteria = Q-iBK*-w
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detachedCriteria.getExecutableCriteria(session); >t9DI
return criteria.list(); g9Dynm5
} uQ
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}, true); /V/)A\g
} kxrYA|x
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public int getCountByCriteria(final ME>Sh~C\
{qSMJja !t
DetachedCriteria detachedCriteria){ jc32s}/H
Integer count = (Integer) Rc93Fb-Zp
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getHibernateTemplate().execute(new HibernateCallback(){ -j Nnx*
publicObject doInHibernate non5e)w3@
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(Session session)throws HibernateException { ^!O!HMX0
Criteria criteria = kTzO4s?
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detachedCriteria.getExecutableCriteria(session); i6FJG\d
return =(R3-['QIb
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criteria.setProjection(Projections.rowCount bO('y@)X
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()).uniqueResult(); ?hrz@k|
} 1JOoICjB
}, true); mU[
return count.intValue(); 8B "^}y\0
} i}f" 'KW
} 44k8IYC*o
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用户在web层构造查询条件detachedCriteria,和可选的 1<Uv4S
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 #N"QTD|i
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PaginationSupport的实例ps。 UsCaO<A
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ps.getItems()得到已分页好的结果集 ^%\MOjSN
ps.getIndexes()得到分页索引的数组 fU.z_T[@
ps.getTotalCount()得到总结果数 '!MKZKer
ps.getStartIndex()当前分页索引 #Hl?R5
ps.getNextIndex()下一页索引 k O.iJcZg
ps.getPreviousIndex()上一页索引 tQ.H/;
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Vhe$vH
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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 Oe "%v;-
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一下代码重构了。 d+
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我把原本我的做法也提供出来供大家讨论吧: HHs!6`R$0c
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首先,为了实现分页查询,我封装了一个Page类: ;R@D
java代码: Ef@Et(f_mQ
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/*Created on 2005-4-14*/ Y%}N@ ,lT
package org.flyware.util.page; b9v<Jk
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/** LEX @hkh
* @author Joa }iUpBn
* $(*>]PC+)
*/ Krl9O]H/[
publicclass Page { 3kwkU
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/** imply if the page has previous page */ Nn U`u.$D
privateboolean hasPrePage; YJ~mcaw
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/** imply if the page has next page */ @tJic|)x
privateboolean hasNextPage; ',rK\&lL6
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/** the number of every page */ (S?DKPnR
privateint everyPage; [r'A8!/|[
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/** the total page number */ Imq-5To#
privateint totalPage; 1xh7KBr,
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/** the number of current page */ @YG-LEh
privateint currentPage; HIC!:|
8%xBSob{j
/** the begin index of the records by the current 6E9/z
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query */ ,H^!G\
privateint beginIndex; *v?kp>O
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/** The default constructor */ s{j A!T}
public Page(){ Z&P\}mm
ts=:r
} M CP GDr
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/** construct the page by everyPage 5NH4C
* @param everyPage siT`O
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* */ rPqM&&+
public Page(int everyPage){ U%[ye0@:
this.everyPage = everyPage; {8`$~c
} 5Dz$_2oM3
bS954d/
/** The whole constructor */ RVLVY:h|F
public Page(boolean hasPrePage, boolean hasNextPage, n${k^e-=
M}f(-,9
t8rFn
int everyPage, int totalPage, SW'eTG
int currentPage, int beginIndex){ S6a\KtVa
this.hasPrePage = hasPrePage; Im@OAR4,R
this.hasNextPage = hasNextPage; eF9GhwE=
this.everyPage = everyPage; Zj'%c2U_
this.totalPage = totalPage; ' VKD$q
this.currentPage = currentPage; T?1V%!a;f
this.beginIndex = beginIndex; ~1[n@{*: (
} z ynu0X
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/** zB~< @
* @return lG%697P
* Returns the beginIndex. :zPK
*/ y_=y%
publicint getBeginIndex(){ D&D6!jz
return beginIndex; |iUC\F=-
} M*kE |q/K
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/** q!@!eC[b
* @param beginIndex $D#h, `
* The beginIndex to set. V-n{=8s
*/ J'$NBws
publicvoid setBeginIndex(int beginIndex){ E5M/XW\E6
this.beginIndex = beginIndex; {7z]+ h
} G[yzi
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/** L-C^7[48=
* @return V<jj'dZfW
* Returns the currentPage. Zd>sdS`#r
*/ Q47R`"
publicint getCurrentPage(){ ,)#rD9ZnC
return currentPage; 5~@-LXqL
} j9hfW'
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/** C9sU^]#F
* @param currentPage A#T"4'#?<
* The currentPage to set. M-Efe_VRQc
*/ c]aU}[s1
publicvoid setCurrentPage(int currentPage){ e8^/S^ =&d
this.currentPage = currentPage; 4A6Y
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} : #CWiq("%
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/** d4;$=P
* @return e,_Sj(R8
* Returns the everyPage. ;WX.D]>{W
*/
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publicint getEveryPage(){ f/UU{vX(
return everyPage; aO&{.DO2
} `D~oY=
if|5v^/
/** iIX%%r+
* @param everyPage SefhOh^,V
* The everyPage to set. =JzzrM|V*
*/ BNCM{}e
publicvoid setEveryPage(int everyPage){ I!*P' {lh
this.everyPage = everyPage; _.; PLq~0
} zMbFh_dcq
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/** 5.{=Op!
* @return SQ4^sk_!
* Returns the hasNextPage. bTimJp[b
*/ m1;Htw
publicboolean getHasNextPage(){ p7Wt(A
return hasNextPage; ?5nEmG|kO
} 6)uBUM;i
it\$Pih]
/** oLKliA=q
* @param hasNextPage D r(0w{5
* The hasNextPage to set. Dnw^H.
*/ 5WHz_'c
publicvoid setHasNextPage(boolean hasNextPage){ 7gf(5p5ZV
this.hasNextPage = hasNextPage; #ay/VlD@
} )v_Wn[Y.H
f)T\
/** k+ t(u]
* @return Hvk~BP'
m
* Returns the hasPrePage. yHw @Z
*/ O00;0w u
publicboolean getHasPrePage(){ _{k*JT2
return hasPrePage; SzMh
} hO8xH +;
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/** Wf3BmkZzz
* @param hasPrePage ik(YJw'i7E
* The hasPrePage to set. wkZwtq
*/ s oY\6mHio
publicvoid setHasPrePage(boolean hasPrePage){
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6
this.hasPrePage = hasPrePage; 8C*@d_=q
} NuR7pjNMZ
n5d8^c! 2
/** 17KQ
* @return Returns the totalPage. <)T| HKx
* ulsU~WW7r
*/ #8et91qw
publicint getTotalPage(){ }X{rE|@
return totalPage; vz4(
k/
} >ZOlSLu
A3/[9}(U
/** gEk;Tj
* @param totalPage Yg.[R]
UC
* The totalPage to set. FM6{%}4
*/ Y
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publicvoid setTotalPage(int totalPage){ 9k;,WU(K<
this.totalPage = totalPage; sn:VM HrOT
} -b^dK)wR~
7/~=[#]*
} ]F+|C
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Uwkxc
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h_ 4*?w
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 W_M#Gi/AL
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个PageUtil,负责对Page对象进行构造: GrG'G(NQ
java代码: &YY`XEG59O
VVSt,/SO
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/*Created on 2005-4-14*/ *S*49Hq7c
package org.flyware.util.page; Cl&mz1Y;]1
k'O.1
import org.apache.commons.logging.Log; PyfWIU7O
import org.apache.commons.logging.LogFactory; ra'/~^9
F62 uDyY
/** mce qZv
* @author Joa oVK:A;3T|
* %}TJr]'F
*/ t)W=0iEd9
publicclass PageUtil { =.8n K
y
{*+J`H_G2a
privatestaticfinal Log logger = LogFactory.getLog @LOfqQ$FE
)
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(PageUtil.class); `\VtTS
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/** ~RVlc;W
* Use the origin page to create a new page gf>H-718F
* @param page HFP'b=?`]|
* @param totalRecords fCUx93,>z
* @return ({rcH.:
*/ .9x*YS
publicstatic Page createPage(Page page, int H 0+-$s;f
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totalRecords){ Ph
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return createPage(page.getEveryPage(), q`p0ul,n
5!A:xV]6]
page.getCurrentPage(), totalRecords); Fb1<Ic#
} 1,=:an
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/** J#C4A]A
* the basic page utils not including exception 1P"7.{
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handler <6-73LsHcP
* @param everyPage 3A^AEO
* @param currentPage bxYSZCo*
* @param totalRecords ;N.dzH2yA
* @return page c&bhb[
*/ S}rEQGGR{
publicstatic Page createPage(int everyPage, int g5+m]3#t
bp'%UgA)1
currentPage, int totalRecords){ ]d(Z%
everyPage = getEveryPage(everyPage); Pteti
currentPage = getCurrentPage(currentPage); 5)Z=FUupA~
int beginIndex = getBeginIndex(everyPage, {wM<i
[nHN@p|
currentPage); awR !=\
int totalPage = getTotalPage(everyPage, %0y-f
`=pA;R9
totalRecords); +mBS&FK
boolean hasNextPage = hasNextPage(currentPage, 0#Gm# =F
vKW!;U9~P
totalPage); (7<G1$:z=
boolean hasPrePage = hasPrePage(currentPage); EG^
rh;
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returnnew Page(hasPrePage, hasNextPage, ~6t<`&f
everyPage, totalPage, \3ydNgl
currentPage, >A@yF?
;g8v7>p
beginIndex); %`pi*/(
} qPz_PRje
IR3SP[K"
privatestaticint getEveryPage(int everyPage){ - s'W^(
return everyPage == 0 ? 10 : everyPage; .n_Z0&i/w
} GKEOjaE
8h)7K/!\
privatestaticint getCurrentPage(int currentPage){ 9[\do@
return currentPage == 0 ? 1 : currentPage; XBX`L"0
} 1O,5bi>t7
oMYFfnoAa
privatestaticint getBeginIndex(int everyPage, int 3%r/w7Fc
e~*tQ4
currentPage){ Zc38ht\r;
return(currentPage - 1) * everyPage; z7BFkZ6+
} }9U_4k
28M^F~0
privatestaticint getTotalPage(int everyPage, int WU=EJY}#n
f
uU"
totalRecords){ HZ!<dy3
int totalPage = 0; +68age;dM
P//nYPyzg
if(totalRecords % everyPage == 0) 4`o0?_.'
totalPage = totalRecords / everyPage; N!<l~[rc
else 2N |iOog
totalPage = totalRecords / everyPage + 1 ; 8cvSA&l(D
}+S~Ah?(
return totalPage; _d7;Z%
} ?Qd`Vlp7
^o>WCU =
privatestaticboolean hasPrePage(int currentPage){ h5@7@w%
return currentPage == 1 ? false : true; jR:\D_:
} 3rZPVR$))
_qOynW
privatestaticboolean hasNextPage(int currentPage, %*<Wf4P"
K&{ _s
int totalPage){ \Js*>xA
return currentPage == totalPage || totalPage == (p'/a.bn
hxJKYU^%m
0 ? false : true; p]~PyzG!
}
Jk`l{N
8?'=Aeo
(I;81h`1G
} GU1cMe
dEkS T[Y3
txMC^-J2l
"5$p=|
MUtM^uY
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。 pcOKC 0b.
6W]C`
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 pwSkw J]
/18fpH|
做法如下: hWn-[w/l_
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 Y>E` 7n
RvU'8Y?>w
的信息,和一个结果集List: o9Mr7
java代码: 9P#kV@%(0c
r-WX("Vvh
M
$EHx[*5
/*Created on 2005-6-13*/ |z@AvS[
package com.adt.bo; K'E)?NW69
&01KHJY)/G
import java.util.List; j+lcj&V#
[z_ztK1
import org.flyware.util.page.Page; 8OS^3JS3"
]H`pM9rC
/** qM
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* @author Joa SuV3$-);z
*/ e !w{ap8u
publicclass Result { z}r
@b5$WKPX
private Page page; U:
<
D^t:R?+
private List content; h y\iot
3RlNEc%)
/** G_k_qP^:
* The default constructor j39"iAn
*/ CNWA!1n^Hy
public Result(){ LH@Kn?R6
super(); PCH$)F4^
} zqXDD; w3
k0b6X5
/** I&&;a.
* The constructor using fields $RC)e7
* olHmRJ
* @param page 1p-<F3;
* @param content NJ$Qm.S
*/ egWfKL&iy
public Result(Page page, List content){ QPFv]^s(
this.page = page; 3Zp q#
this.content = content; Smh=Q4,W
} t`eIkq|NxI
PVQn$-aq1
/** \2Q#'
* @return Returns the content. >V%.=})K
*/ SHnMqaq
publicList getContent(){ :hf%6N='kI
return content; r"VNq&v]9
} zCS }i_ p
q03nu3uDI
/** yZmeke)_
* @return Returns the page. w H`GzB"
*/ XHJ/211
public Page getPage(){ A=D
G+z''
return page; O/&Qzt
} AZ\f6r{
jS#YqVuN
/** }Os7[4RW
* @param content 4dI`
* The content to set. Ga
<=Di):
*/ ')WS :\J
public void setContent(List content){ 7VLn$q]:
this.content = content; +\.0Pr
} 1 a%1C`d
W$gjcsv
/** IY@N
* @param page zgxMDLH
* The page to set. J8&0l&~6
*/ vU#>3[aC
publicvoid setPage(Page page){ 8xoC9!xt
this.page = page; PoRP]Q*n
} 8&7zV:=
} WjvgDNk
r;"Qu
:vE\r#hJ"
]-OF3+l4
C&.Q|S2_
2. 编写业务逻辑接口,并实现它(UserManager, 0"mr*hyj
y@ c[S;
UserManagerImpl) Jg6@)<n
java代码: PD^Cj?wm
w6AG:u
c$;Cpt@-j
/*Created on 2005-7-15*/ ;F/w&u.n
package com.adt.service; #0Z%4W Q
@3?dI@i(
import net.sf.hibernate.HibernateException; |O*?[|`H
uLt31G()
import org.flyware.util.page.Page; 8HWEObRY
2KNs,4X@
import com.adt.bo.Result; 6'.CW4L
uA\KbA.c;U
/** $$T a
* @author Joa [qxDCuxq
*/ wf~n>e^e
publicinterface UserManager { ~[0^{$rrWs
xv_Z$&9e>l
public Result listUser(Page page)throws rpL]5e!
lt{"N'Gw6
HibernateException; p'=XW#2 >
oK2j PP
} [XD3}'Aa
2&2t8.<
#D%l;Ae
6I\4Yv$N
3Io7!:+
java代码: LP}'upv
E> YE3-]
KWn.
/*Created on 2005-7-15*/ S|_"~Nd=
package com.adt.service.impl; nO8e'&|
Ne}x(uRn
import java.util.List; mzn#4;m$
^7Z.~A y
import net.sf.hibernate.HibernateException; o_.`&Q6n
<1kK@m -E
import org.flyware.util.page.Page; f|{&Y2h(R
import org.flyware.util.page.PageUtil; =u.hHkx
lR5k1J1n
import com.adt.bo.Result; :\|<7n
import com.adt.dao.UserDAO; j$r2=~1
import com.adt.exception.ObjectNotFoundException; mz3Dt>
import com.adt.service.UserManager; Vd A!tL
6FEIQ#`{
/** (CY#B%*
* @author Joa 9@ :QBe3]
*/ 6f;20dn6
publicclass UserManagerImpl implements UserManager { GNM+sdy+
2E@y0[C?
private UserDAO userDAO; .\"8H1I\T
N"zm
/** GNoUn7Y
* @param userDAO The userDAO to set. n?8xRaEf
*/ "?s
publicvoid setUserDAO(UserDAO userDAO){ q4Y7 HE|ym
this.userDAO = userDAO; x+W,P
} ??,/85lM
QJU\YH%}
/* (non-Javadoc) [(Ihu e
* @see com.adt.service.UserManager#listUser J{PNB{v
\W"p<oo|H
(org.flyware.util.page.Page) $Sd pF-'
*/ r|Q/:UV?w
public Result listUser(Page page)throws $[+)N~
4Xe8j55
HibernateException, ObjectNotFoundException { :-oMkBS
int totalRecords = userDAO.getUserCount(); Wu'9ouw!
if(totalRecords == 0) Hp[i8PJ
throw new ObjectNotFoundException ;9'] na
:KS"&h{ SY
("userNotExist"); Vze vOS
page = PageUtil.createPage(page, totalRecords); 8Z3:jSgk
List users = userDAO.getUserByPage(page); *bUOd'vh
returnnew Result(page, users); #"fn;
} ,s/laZ)V
e@iz`~[
} z>)lp$
X$_pDF&\z
8+H 0
dFmpx%+p
k106fT]eX
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 35 L\
pl/ek0QX
询,接下来编写UserDAO的代码: )&l5I4CIf
3. UserDAO 和 UserDAOImpl: s"p\-Z
java代码: @r(3
4j(`koX_
dVZ~n4
/*Created on 2005-7-15*/ taMcm}*T1
package com.adt.dao; @U@O#+d'ZR
>E3-/)Ti
import java.util.List; %,e,KcP'
E6M*o+Y
import org.flyware.util.page.Page; 8fktk?|
g |H
import net.sf.hibernate.HibernateException; E<7$!P=z`
1DGl[k/zv
/** wN^^_
* @author Joa Gte\=0Wr
*/ |9X2AS Qu
publicinterface UserDAO extends BaseDAO { X*9-P9x(6
ta^$&$l
publicList getUserByName(String name)throws {rn^
zGy+jeH:.
HibernateException; p,!IPWo
*Uy;P>8
publicint getUserCount()throws HibernateException; %(]B1Zg6,
<[ u(il
publicList getUserByPage(Page page)throws W8r"dK
h
B_p
HibernateException; yr?X.Np
Yq4nmr4
} BzV97'
6ND*L0
B I=57
J:O&2g"g
KZa6*,,s
java代码: 6/ T/A+u
!6a;/ys
6']G HDK
/*Created on 2005-7-15*/ \DWKG~r-%
package com.adt.dao.impl; )u4=k(
RCoDdtMo
import java.util.List; <0? r#
}
qq3/K9 #y
import org.flyware.util.page.Page; ovdaK"q2
esq~Ehr=
import net.sf.hibernate.HibernateException; Dy8H(_
import net.sf.hibernate.Query; UZmo?&y
+5 gX6V\
import com.adt.dao.UserDAO; )>U"WZ'<
S%B56|'
/** p=#/H,2
* @author Joa L3'isaz&^
*/ >AY9F|:
public class UserDAOImpl extends BaseDAOHibernateImpl 2|]
<U[
f9
:=6
implements UserDAO { />pAZa
2oOos%0
/* (non-Javadoc) 7FD,TJs
* @see com.adt.dao.UserDAO#getUserByName D:?"Rf{)
.726^2sx
(java.lang.String) ^)a:DKL
*/ t0kZFU
publicList getUserByName(String name)throws cIa`pU,6A
TTbJ9O<43
HibernateException { {P\Ob0)q
String querySentence = "FROM user in class S3$C#mHX
s{{8!Q
com.adt.po.User WHERE user.name=:name"; 1?3+>
Query query = getSession().createQuery GoH.0eQ^
qFLt/
>
(querySentence); 3)9e-@
query.setParameter("name", name); }NRt:JC
return query.list(); )OucJQ
} #3eI4KJ4+l
~l.C-
/* (non-Javadoc) o4@d,uIw^
* @see com.adt.dao.UserDAO#getUserCount() W(?J,8>
*/ ^,?>6O
publicint getUserCount()throws HibernateException { wZbT*rU
int count = 0; Pth4_]US
String querySentence = "SELECT count(*) FROM m=/HUt3(&0
*~cNUyd
user in class com.adt.po.User"; 1vCp<D9<
Query query = getSession().createQuery w (X}
c,ct=m.|6A
(querySentence); *f{4_ts
count = ((Integer)query.iterate().next nD)SR
HU|qeSyel
()).intValue(); yd'cLZd<}
return count; 9&<c)sS&B
} <7B;_3/
;05lwP*r]
/* (non-Javadoc) !=yO72dgLY
* @see com.adt.dao.UserDAO#getUserByPage ]W%rhppC
";jAH GbO
(org.flyware.util.page.Page) 1rU\ !GfR
*/ p)"EenUK
publicList getUserByPage(Page page)throws RZSEcRlN
YnDaBpx
HibernateException { 'd;aAG
String querySentence = "FROM user in class z&um9rXR
6& hiW]Adm
com.adt.po.User"; z~v-8aw
Query query = getSession().createQuery 5H 1x-b
-xJ\/"A
(querySentence); KBI1t$
query.setFirstResult(page.getBeginIndex()) `Pwf?_2n-
.setMaxResults(page.getEveryPage()); -GQ.B{%G
return query.list(); CUjRz5L
} 1hV&/Qr
36.mf_AM
}
!y!s/i&P%
KK-+vq
Qt^6w}&
|L-- j
^BI&-bR@
至此,一个完整的分页程序完成。前台的只需要调用 @:!% Z`
F0r5$Pl*
userManager.listUser(page)即可得到一个Page对象和结果集对象 F%{z EANm
p{SIGpbR&
的综合体,而传入的参数page对象则可以由前台传入,如果用 %VXIiu[
?q5HAIZ`
webwork,甚至可以直接在配置文件中指定。 MzlE
S%7bM~J@
下面给出一个webwork调用示例: 6Hd^qouid
java代码: l|9'l[}&
=aehhs>
R~N%sn
/*Created on 2005-6-17*/
Ox'KC
package com.adt.action.user; >4#\ U!
)%!X,
import java.util.List; "DJ%Yo
Ja@?.gW
import org.apache.commons.logging.Log; g|!=@9[dv
import org.apache.commons.logging.LogFactory; %]O#t<D
import org.flyware.util.page.Page; 1fF\k#BE-%
FOcDBCrOe
import com.adt.bo.Result; }yCgd 5+_
import com.adt.service.UserService; i'#%t/ u
import com.opensymphony.xwork.Action; z_z'3d.r7
b1ZHfe:
/** D[Ld=e8t
* @author Joa D,uT#P
*/ <R#:K7>O
publicclass ListUser implementsAction{ RWn#"~
$,Y?qn/
privatestaticfinal Log logger = LogFactory.getLog <5sfII
9x9E+DG#(
(ListUser.class); ^}GR!990
z&[[4[
private UserService userService; 8ZO~=e
q{)Q ?E
private Page page; jH4Wu`r;m
Ob-k`@_|
privateList users; Je`
w/Hl/U
sM%.=~AN
/* P`M1sON~
* (non-Javadoc) sY'dN_F
* .O.fD
* @see com.opensymphony.xwork.Action#execute() G@S'_
*/ Wy$Q!R=i
publicString execute()throwsException{ R~BW=Dz,e
Result result = userService.listUser(page); C6b(\#g(
page = result.getPage(); XpOQBXbt
users = result.getContent(); PFeK;`[
return SUCCESS; ,u>K##X\
} N" oJ3-~
'MIM_m)H
/** eD 7Rv<
* @return Returns the page. cK+)MFOu+
*/ QgX[?2
public Page getPage(){ {{_,YO^w
return page; :~9F/Jx
} ~w RozV
YyR~pT#ffT
/** b~FmX
* @return Returns the users. KHXnB
*/ sFxciCpN
publicList getUsers(){ L"!BN/i_
return users; ^zaN?0%S33
} meV
RdQ
\Tj(]
/** Yt;.Z$i ,
* @param page $eBE pN
* The page to set. ;q$O^r~
*/ Zx]"2U#
publicvoid setPage(Page page){ _/!IjB:(70
this.page = page; !xK`:[B
} ^UK6q2[
/P|jHK|{
/** "2bCq]I0
* @param users }mC-SC)oSi
* The users to set. -.E<~(fad
*/
`#lNur\x
publicvoid setUsers(List users){ ),)]gw71QW
this.users = users; 5<ycF_
} jM3{A;U2
Sc*O_c3D
/** Kq;Yb&
* @param userService wy$9QN
* The userService to set. f z8eL:i:
*/ `=Hh5;ep
publicvoid setUserService(UserService userService){ .r?-O{2t
this.userService = userService; Ui7S8c#tH
} ;HJ|)PN5L
} \6xVIQ& 0
/%U+kW
jC<!Ny-$
i4N'[ P}
eVDI7W:(Sn
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, Khxl'qj
b^\u
P
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 B@l/'$G
[L,Tf_t^Y
么只需要: Nq)=E[$
java代码: M: qeqn+
R1FBH:Iu
Llk4 =p
<?xml version="1.0"?> %@5f+5{i!z
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork IXugnvyV
Z*QsDS
1.0//EN" "http://www.opensymphony.com/xwork/xwork- V 3-5:z
},'2j
1.0.dtd"> -Vk+zEht
jYRwtP\
<xwork> |jniI(
0I4RZ.2*Y
<package name="user" extends="webwork- x(7K=K']
%J?;@ G)r
interceptors"> m#mM2Guxe
&CFHH"OsT
<!-- The default interceptor stack name tQB+_q
z
Y6/'gg'&5
--> ao<@a{G
<default-interceptor-ref ]%3o"|
'QjX2ytgX
name="myDefaultWebStack"/> _gjsAbM
r"SuE:D
<action name="listUser" Pm6/sO
-#H>kbs
class="com.adt.action.user.ListUser"> %<JjftNQ
<param
Q d]5e
[ottUS@
name="page.everyPage">10</param> c-!rJHL`
<result +s
c|PB
9. Q;J#;1
name="success">/user/user_list.jsp</result> 3HC aZ?Ry'
</action> 6|t4\'
Sb+pB58&N
</package> ;=Jj{FoG%
eXWiTi@
</xwork> Z}TuVE
#[C|%uq
9`+c<j4/B
a -,!K
I2(5]85&]s
d>eVR
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 9 W><m[O
_` |Hk2O
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。 as-
Z)h[B
2c@R!*
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 yv^j~
qm&}^S
z_~f/
y.26:c(
deHhl(U;
我写的一个用于分页的类,用了泛型了,hoho aR ao\Wp|
u{yENZ^P
java代码: mnu4XE#|
R_:47.qq
YA O,
rh
package com.intokr.util; RxY
;'NY
*g]q~\b/;
import java.util.List; 3 :X3n\z
tbF>"?FY/
/** )uiYu3 I
* 用于分页的类<br> QpwOrxI}
* 可以用于传递查询的结果也可以用于传送查询的参数<br> /Y:&307q
* lcHwKd
* @version 0.01 #ok1qT9_
* @author cheng ht^U VV2
*/ MDkIaz\U
public class Paginator<E> { ixJUq o
privateint count = 0; // 总记录数 39!o!_g
privateint p = 1; // 页编号 =q|fe%#
privateint num = 20; // 每页的记录数 -X@;"0v
privateList<E> results = null; // 结果 RJs_ S
Q, E!Ew3
/** d9/E^)TT
* 结果总数 syh0E=If_
*/ f{e*R#+&
publicint getCount(){ v)JQb-<
return count; ^v3+w"2
} y? [*qnPj
RCt)qh+
publicvoid setCount(int count){ ~QdwoeaD
this.count = count; AW'tZF"
} v >3ctP{
Y,D\_il_
/** P's <M
* 本结果所在的页码,从1开始 +2oZB]GPL
* F dv&kK!
* @return Returns the pageNo. :kZ2N67
*/ KHr8\qLH
publicint getP(){ Ao96[2U6
return p; iy
tSC
} LWbWj ^
5d}PrYa
/** -lL*WA`
* if(p<=0) p=1 `@.YyPxX\
* q1dYiG.-Z
* @param p z,rWj][P
*/ any\}
publicvoid setP(int p){ 8zj09T[
if(p <= 0) @YwaOc_%
p = 1; ZJ=C[s!wu
this.p = p; ]^
O<WD
} N83RsL "}_
SO p%{b
/** `*oLEXYN
* 每页记录数量 A#1y>k
*/ !.t'3~dUf$
publicint getNum(){ SgXXitg9+
return num; l}Xmm^@)
} UjKHGsDi4
Tao lX*$5
/** Kg](kP
* if(num<1) num=1 XVv7W5/q]
*/ dN*<dz+4r
publicvoid setNum(int num){ [ z$J
if(num < 1) Kv#daAU
num = 1; 3b&W=1J
this.num = num; g<.8iW 'c
} r kD4}jV
D[tGbk
/** !-MG"\#Wq
* 获得总页数 :m$%D]WY
*/ gwqK`ww
publicint getPageNum(){ kT$4X0}
return(count - 1) / num + 1; r*p%e\ 3
} 'xi..
VR:b1XWX
/** F 1zc4l6
* 获得本页的开始编号,为 (p-1)*num+1 }bnkTC
*/ U73`HDJ
publicint getStart(){ 57MoO
return(p - 1) * num + 1; ^#t<ILUa
} YJL=|v
#&5\1Qu
/** :<(<tz7dj
* @return Returns the results. <1LuYEDq
*/ 5g5pzww
publicList<E> getResults(){ k m|wB4
return results; *|3z($*U]
} $?GO|.59
iLI]aZ
public void setResults(List<E> results){ O0l;Qi
this.results = results; {vH8X(m
} $Yxy(7d7w
U{}7:&As
public String toString(){ j,-7J*A~
StringBuilder buff = new StringBuilder (1HN, iJy
?d0Dfqh_
(); 3//v{ce1]
buff.append("{"); Y'~&%|9+T
buff.append("count:").append(count); ;5l|-&{@*
buff.append(",p:").append(p); fh3
6
buff.append(",nump:").append(num); aRwBxf
buff.append(",results:").append v%- V|L
&ivIv[LV
(results); H}~^,B2;
buff.append("}"); srkOad
return buff.toString(); cA\W|A)
} ]rm=F]W/n
q<8HG_
} D-!%L<<
OR9){qP
J)->
7h=