Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 V
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 eTbg7"waA
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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 JeCg|@
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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 ]JXKZV8$0
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分页支持类: e#S0Fk)z
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java代码: ^x m$EY*Y,
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package com.javaeye.common.util; tU:EN;H
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import java.util.List; cBXWfv4
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publicclass PaginationSupport { [0y$! f4
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publicfinalstaticint PAGESIZE = 30; 2oCkG~j
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privateint pageSize = PAGESIZE; =Vw
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privateList items; Ba'LRz
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privateint totalCount; )Xtnk
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privateint[] indexes = newint[0]; UbamB+QT
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privateint startIndex = 0; Wl-<HR!n
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public PaginationSupport(List items, int \ck+GW4&
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totalCount){ ~xLJe`"JUx
setPageSize(PAGESIZE); %$5H!!~o
setTotalCount(totalCount); r]Lc9dL
setItems(items); ~Z'w)!h
setStartIndex(0); sN6N >{
} {{yZ@>o6
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public PaginationSupport(List items, int j+-P :xvP
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totalCount, int startIndex){ -E4XIn
setPageSize(PAGESIZE); Sa1l=^
setTotalCount(totalCount); iyta;dw9
setItems(items); >>{FzR
setStartIndex(startIndex); %9oYw9H!
} O1'm@
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public PaginationSupport(List items, int "Wo,'8{v
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totalCount, int pageSize, int startIndex){ i0jBZW"_1$
setPageSize(pageSize); Bi,;lR5
setTotalCount(totalCount); GH1"xR4!
setItems(items); [`RX*OH2
setStartIndex(startIndex); \QE)m<GUe
} ^=
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publicList getItems(){ %zk$}}ti.
return items; Y!J>U
} 7R!5,Js+
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publicvoid setItems(List items){ ={>Lrig:l
this.items = items; $37
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} %ru;;h
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publicint getPageSize(){ E.|-?xQ6
return pageSize; rgmF: C
} c(;a=n(E#
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publicvoid setPageSize(int pageSize){ ,Uhb
this.pageSize = pageSize; >9e(.6&2XZ
} G6@M&u5RT
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publicint getTotalCount(){ I`KQ|h0%
return totalCount; w }^ I
} ?`zXLY9q7
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publicvoid setTotalCount(int totalCount){ n_ lo`
if(totalCount > 0){ &e-U5'(6v_
this.totalCount = totalCount; r%:+$aIt
int count = totalCount / h\v'9
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pageSize; D%6;^^WyUx
if(totalCount % pageSize > 0) om?-WJI
count++; |sRipWh
indexes = newint[count]; Mi'8
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for(int i = 0; i < count; i++){ 26T "XW'_
indexes = pageSize * AdRX`[ik
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i; iu&wO<)+?
} AKMm&(fh%
}else{ iY"l}.7)
this.totalCount = 0; \%^%wXfp
} ]BR,M4
} U!U$x74D5
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publicint[] getIndexes(){ {ZY+L;eg1
return indexes; gUyR_5q)8l
} !,V{zTR
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publicvoid setIndexes(int[] indexes){ "HE^v_p
this.indexes = indexes; \+aC"#+0
} Y"A/^]
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publicint getStartIndex(){ y ]?V~%
return startIndex; V< k8N^
} C8z{XSo
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publicvoid setStartIndex(int startIndex){ -B86U6^s
if(totalCount <= 0) ^%O]P`$
this.startIndex = 0; xhcK~5C
elseif(startIndex >= totalCount) ZXm/A0)S
this.startIndex = indexes 4:g R r
}.s~T#v
[indexes.length - 1]; M|:UwqV>
elseif(startIndex < 0) Yw#2uh
this.startIndex = 0; tHzZ@72B7
else{ pAT7)Ch
this.startIndex = indexes fbUr`~Y"
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[startIndex / pageSize]; As>_J=8} 3
} ?lP':'P
} E*+{t~
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publicint getNextIndex(){ L|p
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int nextIndex = getStartIndex() + Ol!ntNhXm
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pageSize; nqLA}u4IM
if(nextIndex >= totalCount) }iuWAFZbGS
return getStartIndex(); K4kMM*D
else ,G)r=$XU
return nextIndex; T#>7ub
} *QH28%^
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publicint getPreviousIndex(){ t. ;LnrY
int previousIndex = getStartIndex() - ~?(N
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pageSize; 7Hs%Cc"
if(previousIndex < 0) EY tQw(!Q
return0; fk&8]tK4
else ^pUHKXihD
return previousIndex; >p"c>V& 8
} U*)8G
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} aTt12Sc
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抽象业务类 b9l;a+]d
java代码: OLE[UXD-E
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/** OynXkH]0T+
* Created on 2005-7-12 <[-nF"Q
*/ xoN3
package com.javaeye.common.business; i*Z"Me
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import java.io.Serializable; mGK|ihYu
import java.util.List; 6ZP"p<xX
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import org.hibernate.Criteria; n^g|Ja
import org.hibernate.HibernateException; ynQ: >tw
import org.hibernate.Session; P09;ng67
import org.hibernate.criterion.DetachedCriteria; Hg=";,J
import org.hibernate.criterion.Projections; ZusEfh?
import P(f0R8BE
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org.springframework.orm.hibernate3.HibernateCallback; H5Io{B%=
import y2^Y/)
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org.springframework.orm.hibernate3.support.HibernateDaoS ATK_DEAu
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upport; ()6wvu}
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import com.javaeye.common.util.PaginationSupport; =Lf,?"S
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public abstract class AbstractManager extends s*-n^o-
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HibernateDaoSupport { I+tb[*X+
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privateboolean cacheQueries = false; q-}Fvel u
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privateString queryCacheRegion; UdpF@Q
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publicvoid setCacheQueries(boolean gMzcTmbc8
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cacheQueries){ @}}$zv6l,
this.cacheQueries = cacheQueries; ;6>2"{NW
} ]7Tkkw$
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publicvoid setQueryCacheRegion(String H}hiT/+$
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queryCacheRegion){ KbA?7^zo`
this.queryCacheRegion = n$$SNWgM
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queryCacheRegion; n(;|q&3
} tFp Ygff<
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publicvoid save(finalObject entity){ x-^`~p
getHibernateTemplate().save(entity); z=q3Zo
} K/IWH[
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publicvoid persist(finalObject entity){ Ab{ K<:l
getHibernateTemplate().save(entity); )b)-ZS7
} xc=b
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publicvoid update(finalObject entity){ lh7jux
getHibernateTemplate().update(entity); Nn!+,;ut
} W*Zkc:{eB
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publicvoid delete(finalObject entity){ ~?d Nd
getHibernateTemplate().delete(entity); #h`
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} wl#@lOv-P
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publicObject load(finalClass entity, 9\_eK,*B
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finalSerializable id){ Egg=yF>T
return getHibernateTemplate().load S4Y&
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(entity, id); }fb#G<3
} +BETF;0D
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publicObject get(finalClass entity, '
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finalSerializable id){ vq(0OPj8r[
return getHibernateTemplate().get aX)I3^ar
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(entity, id); M2OIBH4!
} _>(^tCo
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publicList findAll(finalClass entity){ QbkLdM,S*
return getHibernateTemplate().find("from {.C!i{|
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" + entity.getName()); RP[{4Q8
} le/,R@]B9
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publicList findByNamedQuery(finalString 9g'LkP
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namedQuery){ ;oW6 NJ
return getHibernateTemplate
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().findByNamedQuery(namedQuery); }X)&zenz
} ,':fu
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publicList findByNamedQuery(finalString query, Mo?~_|}
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finalObject parameter){ JTO~9>$ B
return getHibernateTemplate de.&`lPRf
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().findByNamedQuery(query, parameter); %b&".mN
} p>RNPrT
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publicList findByNamedQuery(finalString query, }vxw*8d?
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finalObject[] parameters){ -JMdE_h
return getHibernateTemplate {XR6>]
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().findByNamedQuery(query, parameters); H?<N.Dq
} C'\-
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publicList find(finalString query){ ?pr9f5
return getHibernateTemplate().find IUE~_7
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(query); -+(jq>t
} [#-b8Cu
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publicList find(finalString query, finalObject 7Ri46Tkt
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parameter){ ~
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return getHibernateTemplate().find wvO|UP H\
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(query, parameter); 0
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} R.jIl@p
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public PaginationSupport findPageByCriteria fd+hA
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(final DetachedCriteria detachedCriteria){ _"?.!
return findPageByCriteria %<k2#6K
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); FQu8vwV6>
} )Xk0VDNp$/
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public PaginationSupport findPageByCriteria O@u?h9?cf>
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(final DetachedCriteria detachedCriteria, finalint 7mI:|G
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startIndex){ =5J7Hw&K
return findPageByCriteria e<3K;Q
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(detachedCriteria, PaginationSupport.PAGESIZE, aZ2!i
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startIndex); JlH&??
} K(q+
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public PaginationSupport findPageByCriteria <e Th
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(final DetachedCriteria detachedCriteria, finalint <'qeXgi
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pageSize, ykl
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finalint startIndex){ rSZd!OQ
return(PaginationSupport) 'FqQzx"r
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getHibernateTemplate().execute(new HibernateCallback(){ k.5u
publicObject doInHibernate xQ}pu2@d
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(Session session)throws HibernateException { )U~=Pf"
Criteria criteria = 'qZW,],5
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detachedCriteria.getExecutableCriteria(session); .u*0[N
int totalCount = S?> HD| Z
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((Integer) criteria.setProjection(Projections.rowCount AP68V
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()).uniqueResult()).intValue(); ;XF:\<+
criteria.setProjection >"|B9Woc
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(null); iX0i2ek
List items = \]</w5 Pi,
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criteria.setFirstResult(startIndex).setMaxResults 9{RB{<Se!
}p}[j t
(pageSize).list(); }=%oX}[
PaginationSupport ps = Wr<j!>J6Ki
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new PaginationSupport(items, totalCount, pageSize, wG~`[>y (
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startIndex); "3Uv]F
return ps; !Fca~31R'
} M$y+q
^
}, true); FG%X~L<d,)
} ?ATOXy
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public List findAllByCriteria(final iL7DRQ1
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DetachedCriteria detachedCriteria){ ZvNJ^Xz
return(List) getHibernateTemplate /35R u}c
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().execute(new HibernateCallback(){ u$>4F|=T
publicObject doInHibernate /RNIIY~w
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(Session session)throws HibernateException { tQ8.f
Criteria criteria = 695V3R 7
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detachedCriteria.getExecutableCriteria(session); x}_]A$nV
return criteria.list(); Zo|.1pN
} !ipR$ dM
}, true); \?Z{hmN
} Q3
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public int getCountByCriteria(final NL!u<6y
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DetachedCriteria detachedCriteria){ =8t]\Y?
Integer count = (Integer) +aJ>rR
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getHibernateTemplate().execute(new HibernateCallback(){ 1M}5>V{
publicObject doInHibernate /.3}aj;6
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(Session session)throws HibernateException { N9jH\0nG
Criteria criteria = Hw7;;HK
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detachedCriteria.getExecutableCriteria(session); Ka[t75~;
return QIB\AAclO
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criteria.setProjection(Projections.rowCount 8 7BHq)
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()).uniqueResult(); wCr(D>iM
} Q?nN!eT
}, true); U*i{5/$
return count.intValue(); ;*Ivn@L
} oE+R3[D?r
} 2^y^q2(r
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用户在web层构造查询条件detachedCriteria,和可选的 bL'aB{s
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 nSW=LjrO~<
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PaginationSupport的实例ps。 "Q!(52_@J
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ps.getItems()得到已分页好的结果集 :<hXH^n
ps.getIndexes()得到分页索引的数组 F@mQQ
ps.getTotalCount()得到总结果数 jFASX2.p
ps.getStartIndex()当前分页索引 S<VSn}vn
ps.getNextIndex()下一页索引 <J`0mVOX
ps.getPreviousIndex()上一页索引 L\@I*QP
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 kMb}1J0i"
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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 _CmOd-y
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一下代码重构了。 )2bvQy8K
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我把原本我的做法也提供出来供大家讨论吧: D)j(,vt
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首先,为了实现分页查询,我封装了一个Page类: )/pU.Z/
java代码: DVSL [p?_
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/*Created on 2005-4-14*/ te3}d'9&|
package org.flyware.util.page; y9x w
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/** TygW0b 1
* @author Joa K('hC)1
* 7JEbH?lEN
*/ wgamshm"d
publicclass Page { 'eLqlu|T
d8[J@M53|T
/** imply if the page has previous page */ L1cI`9
privateboolean hasPrePage; ZUoxMm
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/** imply if the page has next page */ w8MG(Lq1"
privateboolean hasNextPage; @JD;k>
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/** the number of every page */ 2w["aVr
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privateint everyPage; ,1 [q^-9
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/** the total page number */ )n2 re?S
privateint totalPage; Fs9I7~L3
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/** the number of current page */ lfqiyYFm
privateint currentPage; ~]nSSD)\
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/** the begin index of the records by the current W3MU1gl6k{
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query */ tasUZ#\6
privateint beginIndex; BW 4%l
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/** The default constructor */ ~GL]wF2#
public Page(){ n ~shK<!C
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} (NF~Ck$#q
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/** construct the page by everyPage )N7Y^CN~
* @param everyPage %-c*C $
* */ hw=
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public Page(int everyPage){ 3HcQ(+Z
this.everyPage = everyPage; nlW +.a[
} 7ccO93Mz
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/** The whole constructor */ {bJ`~b9e
public Page(boolean hasPrePage, boolean hasNextPage, "nw;NIp!
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int everyPage, int totalPage, e[&L9U6GW-
int currentPage, int beginIndex){ \$*7 >`k
this.hasPrePage = hasPrePage; LUM@#3&
this.hasNextPage = hasNextPage; 0{,Z{&E
this.everyPage = everyPage; dep=&
this.totalPage = totalPage; rA%usaW
this.currentPage = currentPage; -o$QS,
this.beginIndex = beginIndex; '}B+r@YCN
} #a'Ex=%rM
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/** tjdaaN#,V
* @return L?WFmn
* Returns the beginIndex. gG*X^Uo
*/ >[*8I\*@n
publicint getBeginIndex(){ {L/ tst#C
return beginIndex; Y@N,qHtz
} SqEgn}m$
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/** 2O.i\cH
* @param beginIndex ]6TATPIr
* The beginIndex to set. ms*(9l.hOK
*/ I%sFqh>
publicvoid setBeginIndex(int beginIndex){ U%q7Ai7
this.beginIndex = beginIndex; 4QvsBpz@
} eU".3`CtY
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/** '>cKH$nVC}
* @return 95A1:A^t
* Returns the currentPage. Xq_5Qv
*/ mOy^vMa
publicint getCurrentPage(){ ^c^#dpn
return currentPage; Fcd3H$Na;
} ST:A<Da"
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/** ]rWgSID
* @param currentPage S|7!{}
* The currentPage to set. WvBc#s-
*/ ow_W%I=6
publicvoid setCurrentPage(int currentPage){ {2=jAz'?
this.currentPage = currentPage; pTPi@SBaP{
} lI *o@wQg
= \'}g?
/** n
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* @return ==3dEJS
* Returns the everyPage. YKH\rN6X
*/ QdL`|
publicint getEveryPage(){ o0ifp=V
y
return everyPage; ADDSCY=,
} ++6`sMJ
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/** *AO,^R&e.
* @param everyPage
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* The everyPage to set. jQ2Ot <
*/ Pv_Jm
publicvoid setEveryPage(int everyPage){ 9N@W\DT
this.everyPage = everyPage; ,z;cbsV-{
} ]P.'>4
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/** `j,Yb]~s79
* @return x3 q]I 8q
* Returns the hasNextPage. ^@3sT,M,S
*/ sz:g,}~h
publicboolean getHasNextPage(){ fVF2-Rh=
return hasNextPage; n>ULRgiT:o
} fZ0M%f
=G7m)!
/** cq}EZ@ .
* @param hasNextPage `A w^H!
* The hasNextPage to set. B8f8w)m
*/ `|{-+m
publicvoid setHasNextPage(boolean hasNextPage){ oW ::hB
this.hasNextPage = hasNextPage; "P7nNa
} ;<&*rnH
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/** wSa)*]%
* @return &dM.
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* Returns the hasPrePage. 41`n1:-]
*/ R=gb'
publicboolean getHasPrePage(){ lR )67a
return hasPrePage; &,zq%;-f
} kD=WO4}
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/** )'l:K.F
* @param hasPrePage AL9chYP}/
* The hasPrePage to set. ~;l@|7wGz
*/ ED=V8';D
publicvoid setHasPrePage(boolean hasPrePage){ XGYbnZ~
this.hasPrePage = hasPrePage; \MyLc/Gh5
} 11o.c;
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/** #|L8tuWW
* @return Returns the totalPage. +R3k-' >
* L
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*/ >V-A;S:
publicint getTotalPage(){ [@VP?74
return totalPage; */sS`/Lx
} 3{'Ne}5%I
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/** dP3CG8w5
* @param totalPage i3tg6o4C
* The totalPage to set. GeyvId03H
*/ mk.9OhYY
publicvoid setTotalPage(int totalPage){ uatm/o^~,
this.totalPage = totalPage; l4F%VR4KT
} 2BQ
j
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} g;pcZ9o
s'!Cp=xQF"
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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 |XQIfW]A
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个PageUtil,负责对Page对象进行构造: +ieY:H[
java代码: @:+8?qcP
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/*Created on 2005-4-14*/ @i2E\}
package org.flyware.util.page; CDsSrKhx
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import org.apache.commons.logging.Log; LInz<bc<(
import org.apache.commons.logging.LogFactory; <c2E'U)X
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/** VEWi_;=J1
* @author Joa \:b3~%Fz
* >" )Tf6zw&
*/ z>LUH
publicclass PageUtil { /Lfm&;
J?V? R
privatestaticfinal Log logger = LogFactory.getLog `` ,fodA8
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(PageUtil.class); 9B{k , 1
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/** ~-ia+A6GIV
* Use the origin page to create a new page ]^yFaTfS
* @param page 8[a=OP
* @param totalRecords <^VJy5>
* @return PC~Y8,A|.t
*/ bGN:=Y'
publicstatic Page createPage(Page page, int 6Y^23W F
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totalRecords){ ,c;Kzp>e
return createPage(page.getEveryPage(), H3z:ZTI
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page.getCurrentPage(), totalRecords); 8m-U){r!U^
} \HqNAE2T
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/** "H7dft/
* the basic page utils not including exception Pr3qo4t.L
{+] [5<q
handler t>L;kRujVJ
* @param everyPage FtpK)9/4
* @param currentPage I4'5P}1yp
* @param totalRecords )F}F_Y
* @return page Lb!Fcf|h
*/ ?qP7Y nl
publicstatic Page createPage(int everyPage, int &q3"g*q
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currentPage, int totalRecords){ DGRXd#
everyPage = getEveryPage(everyPage); )B
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currentPage = getCurrentPage(currentPage); Bc(Y(X$PK
int beginIndex = getBeginIndex(everyPage, 0]'7_vDs|
/$i.0$L
currentPage); <NR#Y%}-V
int totalPage = getTotalPage(everyPage, {>}!+k
-`
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totalRecords); v|gw9
boolean hasNextPage = hasNextPage(currentPage, r A`V}>Xj
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totalPage); uW=k K0E
boolean hasPrePage = hasPrePage(currentPage); o
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returnnew Page(hasPrePage, hasNextPage, VQ(j pns5
everyPage, totalPage, gT3_RUF
currentPage, };mA^xO]j
p#&h=,W}
beginIndex); )mg:_K
} 6hw=
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privatestaticint getEveryPage(int everyPage){ sGi"rg#
return everyPage == 0 ? 10 : everyPage; S
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} )SaGH3~*C
?ME6+Z\
privatestaticint getCurrentPage(int currentPage){ [glLre^
return currentPage == 0 ? 1 : currentPage; 35A|BD)q
} ?8I?'\F;
,g%0`SO
privatestaticint getBeginIndex(int everyPage, int D60aH!ft
x/NfZ5e0X
currentPage){ O(#)m>A
return(currentPage - 1) * everyPage; &T+atL `N
} %D UH@j
Z 6t56"u
privatestaticint getTotalPage(int everyPage, int "fQ~uzg="
Pnk5mK$
totalRecords){ yg`j-9[8
int totalPage = 0; {}>0e:51
f~t:L,\,
if(totalRecords % everyPage == 0) ^?-:'<4q$
totalPage = totalRecords / everyPage; Ye\rB\-
else S{Kiy#ltWc
totalPage = totalRecords / everyPage + 1 ; 61Bwb]\f/|
&c` nR<
return totalPage; &SIq2>Q A
} dV*]f$wQ
+dWDxguE{w
privatestaticboolean hasPrePage(int currentPage){ Y4OPEo 5o
return currentPage == 1 ? false : true; e{h<g>7
} rDD:7*z
HeK/7IAqp
privatestaticboolean hasNextPage(int currentPage,
Hu^1[#
3oBtP<yG.
int totalPage){ $'0u |Xy`
return currentPage == totalPage || totalPage == %r<rcY
XQrF4l
0 ? false : true; 4{}FL
} 9?A)n4b;
ko5 @qNq
#Z}Rfk(~
} )mI 05
}Q)#[#e
~t@cO.c
\6S7T$$ 1m
&X`C%h
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。 a_[Eh fE
\(J8#V
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 %OtFHhb
Bp*K]3_
做法如下: &Q9qq~
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 KLU-DCb%
jPC[_g
的信息,和一个结果集List: Ot$-!Y;<
java代码: >L|;|X!m9\
[=x[ w70
Jz?j[
/*Created on 2005-6-13*/ ;5wn67'
package com.adt.bo; `Y+J-EQ
o=u3&liBi
import java.util.List; ~fBtQGdX
WKQ^NEqr3
import org.flyware.util.page.Page; =Ee&da^MB
~{?_p@&n
/** /Y*WBTV'
* @author Joa 7@#>bE6
*/ 4]rnY~
publicclass Result { pny11C
ylUrLQ\
private Page page; .v]IJfRH*
@M<|:Z %.@
private List content; \Lq h j
Y}@&h!
/** g(nPQOs$u
* The default constructor 9Q
-HeXvR
*/ G=)i{oC
public Result(){ +QB"8-
super(); IWBX'|}K
} > pgX^
Q.bXM?V)
/** A_n7w
* The constructor using fields pEw"8U
* O7u(}$D
L
* @param page ]~844Jp
* @param content ioaU*%
*/ OHv[#xGuV?
public Result(Page page, List content){ XoXM^*Vk
this.page = page; SD#]$v
this.content = content; M])ZK
} 6.FY0. i
MU>k,:[
/** ::o lN
* @return Returns the content. _t:$XJ`bTk
*/ 6L:x^bM
publicList getContent(){ J`^ag'
return content; 2C2fGYu
} jnd[6v=C7-
<DpevoF
/** >PB4L_1
* @return Returns the page. <CRP^_c
*/ QU#w%|
public Page getPage(){ d^/3('H6
return page; -HQQw$
} z,|r*\dw
TPVVck-T8
/** B!
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* @param content VzBqjE_
* The content to set. ,l%CX.9
*/ c _\YBe]wJ
public void setContent(List content){ ;V@WtZv
this.content = content; %lL.[8r|
} ]d55m /(
2*rH?dz8E
/** $J4 *U
* @param page IOTR/anu
* The page to set. I6~pV@h^=
*/ 2<li7c59
publicvoid setPage(Page page){ aF8fqu\
this.page = page; jNu9KlN
} Yv
hA_v
} "b?v?V0%C
=b38(\
U0=]
U93}-){m
ygOd69
2. 编写业务逻辑接口,并实现它(UserManager, l;af~ef)'
Ok>gh2e[c
UserManagerImpl) '"y|p+=j:
java代码: o5xAav"+>
`))\}C@k
H|,Oswk~-
/*Created on 2005-7-15*/
zG+R5:
package com.adt.service; 4!$s}V=6
za#s/b$[
import net.sf.hibernate.HibernateException; "mX\&%i6\p
~SQ?BoCI[
import org.flyware.util.page.Page; N03G>fZ
R,)}>X|<
import com.adt.bo.Result; Xm+8
rJFc({ 0
/** qNI,
62
* @author Joa )q0. 0<f
*/ dlU'2Cl7d
publicinterface UserManager { ur*T%b9&
G,TM-l_uw
public Result listUser(Page page)throws qe #P?[
u7bLZU 0
HibernateException; [FK<96.nt
OF%B[h&
} ?in|qevL
dX\.t<
"8'@3$>R=
3VuW#m#j
+${D
java代码: V I,ACj
}YjX3|8zL=
>*@y8u*
/*Created on 2005-7-15*/ (* 1v\Q
package com.adt.service.impl; Av?2<
\2nUa
;
import java.util.List; QF-LU
!(qsD+
import net.sf.hibernate.HibernateException; t^`O{m<
6``'%S'#
import org.flyware.util.page.Page; z?>D_NLX6
import org.flyware.util.page.PageUtil; :1 (p.q=
$|]" W=h
import com.adt.bo.Result; e`d%-9
import com.adt.dao.UserDAO; ,REJt
import com.adt.exception.ObjectNotFoundException; V<D.sd<
import com.adt.service.UserManager; 7~9S 9
mK[)mC
_8
/** \(VTt|}By$
* @author Joa bfA=3S"0
*/ _FXZm50\g{
publicclass UserManagerImpl implements UserManager { p`nPhk,:b
;2@BO-3K
private UserDAO userDAO; +zu(
m~@;~7I x
/** ?s\
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* @param userDAO The userDAO to set. 3ia^\ jw
*/ ?I/qE='*
publicvoid setUserDAO(UserDAO userDAO){ z>jUR,!GT
this.userDAO = userDAO; }K1JU`Lz
} T|6jGZS^|W
!iH-#B-
/* (non-Javadoc) 4&xZ]QC)O5
* @see com.adt.service.UserManager#listUser DVah
AgOp.~*Z~V
(org.flyware.util.page.Page) 5~Cakd]>
*/ I#m-g-J
public Result listUser(Page page)throws Y7#-Fra0W
WX}xmtLs
HibernateException, ObjectNotFoundException { uum;q-"
int totalRecords = userDAO.getUserCount(); F.-R r
if(totalRecords == 0) lE!a
throw new ObjectNotFoundException nt;haeJ
S{FROC~1R
("userNotExist"); %YSpCI
page = PageUtil.createPage(page, totalRecords); ?q(\=;Y
List users = userDAO.getUserByPage(page); &ZghMq~
returnnew Result(page, users); GiP`dtK
} [01.\eh
'\Jj8oJQj
} B.g[c97
y_*PQZ$c<
{88gW\GL
UbEb&9}
CPVjmRUF|
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 lY~4'8^
HS{(v;
询,接下来编写UserDAO的代码: *+TH#EL2
3. UserDAO 和 UserDAOImpl: } X^|$
java代码: %{(x3\ *&
hX`hs-*qM
o;W`4S^
/*Created on 2005-7-15*/ 1x@qkL6
package com.adt.dao; gzjR6uz
rgSOS-ox
import java.util.List; K TsgJ\W
7SlsnhpW
import org.flyware.util.page.Page; +Vo}F
qOSg!aft{Q
import net.sf.hibernate.HibernateException; J8M$k/"X
Zm"{V iv]
/** %honO@$
* @author Joa q(zJ%Gv)
*/ %VzKqh
publicinterface UserDAO extends BaseDAO { :C}2=
2<`.#zIds
publicList getUserByName(String name)throws fV v.@HL{
vj51
g@
HibernateException; ZA Jp%
masT>vM
publicint getUserCount()throws HibernateException; d"5oD@JG:
Y4cYZS47
publicList getUserByPage(Page page)throws 1"pI^Ddt
!).}u,*'no
HibernateException; (RUT{)p[
+2K :qvzZ
} i^_#%L
q}/WQ]p} <
uKz,SqX
i
`s|,"0o
H;U)b{
java代码: Mn$]I) $
Kx.X 7R
2:BF[c`
/*Created on 2005-7-15*/ 9Ro6fjjE
package com.adt.dao.impl; ,h{A^[yl
{&P
FXJ
import java.util.List; ? Zc"C
Rx*BwZ
import org.flyware.util.page.Page; `%E8-]{uS
X=6y_^
import net.sf.hibernate.HibernateException; \S*$UE]uG
import net.sf.hibernate.Query; ,bM-I2BR
ly4s"4v
import com.adt.dao.UserDAO; P7 ]z
Q~MC7-n>
/** Q.9qImgN
* @author Joa 5GA\xM-
*/ LAP6U.m'd
public class UserDAOImpl extends BaseDAOHibernateImpl tV_t6x_.
Tx1vL
implements UserDAO { ?E9D Xg
<W`#gn0b6
/* (non-Javadoc) 4\pWB90V
* @see com.adt.dao.UserDAO#getUserByName j
,)P9V
DbZ0e5
(java.lang.String) &n[~!%(
*/ i\4hR?
publicList getUserByName(String name)throws KJ?y@Q
mAeuw7Ni
HibernateException { 'S<%Xm
String querySentence = "FROM user in class L>!8YUz7p$
TDg@Tg0
com.adt.po.User WHERE user.name=:name"; :qR=>n=
Query query = getSession().createQuery 'lo
o7TN,([W
(querySentence); RQkyCAGx
query.setParameter("name", name); $55U+)C<
return query.list(); 9D 0dg(
} -UZ@G~K
]&ixhW
/* (non-Javadoc) 7QVuc!V
* @see com.adt.dao.UserDAO#getUserCount() Uz608u
*/ R7s|`\
publicint getUserCount()throws HibernateException { F(
Ak
int count = 0; 'JZJFE7Z
String querySentence = "SELECT count(*) FROM 6AvHavA^Y
ZkP{[^6d\
user in class com.adt.po.User"; >#}2J[2HQ
Query query = getSession().createQuery dl5=q\1=
KQld YA|m
(querySentence); R8-^RvG
count = ((Integer)query.iterate().next R//$r%a
2oZ9laJO
()).intValue(); X 6lH|R
return count; ;' nL:\
} _1*7Z=|
1`LXz3uBe
/* (non-Javadoc)
0G <hn8>
* @see com.adt.dao.UserDAO#getUserByPage KtB!"yy#
Z?NEO>h7
(org.flyware.util.page.Page) Nwc!r(
*/ joXfmHB}
publicList getUserByPage(Page page)throws $&Kq*m 0g
kvGCbRC
HibernateException { 'r} zY-FM`
String querySentence = "FROM user in class 3L_I[T$s
TwvAj#j
com.adt.po.User"; Q<6P. PTya
Query query = getSession().createQuery ?X9]HlH
Cs@ +r
(querySentence); 6al=Cwf
query.setFirstResult(page.getBeginIndex()) #.5vC5
.setMaxResults(page.getEveryPage()); y/? &pKH^
return query.list(); _P,^_%}V06
} Te{ *6-gO3
BHj\G7,S
} B|%tE{F
02JoA+
zTo8OPr
~u&|G$1!0
W~ULc9
至此,一个完整的分页程序完成。前台的只需要调用 6QZ5|T ]
q
(+ZwaV@
userManager.listUser(page)即可得到一个Page对象和结果集对象 `@`1pOb
RGD]8mw
的综合体,而传入的参数page对象则可以由前台传入,如果用 td{O}\s7D
~%#mK:+
webwork,甚至可以直接在配置文件中指定。 `C_'|d<HA
2UP,Tgn..
下面给出一个webwork调用示例: V%CUMH =U
java代码: *zVvQ=
la$%H<,7
MS<SAD>w
/*Created on 2005-6-17*/ =l942p
package com.adt.action.user; E-ZRG!)[v
E1Q0k5@
import java.util.List; ekQrW%\3
kw,$NK'
import org.apache.commons.logging.Log; /.V0ag'G
import org.apache.commons.logging.LogFactory; #\4 b:dv
import org.flyware.util.page.Page; Qu%D
Di Or{)a
import com.adt.bo.Result; ?mRE'#
import com.adt.service.UserService; },+~F8B
import com.opensymphony.xwork.Action; #T~&]|{,
F9XT
lA
/** X1A<$Am1
* @author Joa Vf-5&S&9
*/ Omag)U)IPh
publicclass ListUser implementsAction{ {.k)2{
7;LO2<|1
privatestaticfinal Log logger = LogFactory.getLog h<p3'
v })Q
(ListUser.class); hPdx(E)8!d
80ZnM%/}
private UserService userService; Y/U{Qc\6
ivrXwZ7jT
private Page page; h ?#@~
jB@4b'y
privateList users; !rTmR@e$/
(:\LWJX0=
/* (paf2F`~#
* (non-Javadoc) S7n"3.k
* X)uDSI~
* @see com.opensymphony.xwork.Action#execute() q42FPq
*/ ua
8m;>R
publicString execute()throwsException{ FUeq
\Wuo
Result result = userService.listUser(page); *+lsZ8'^C
page = result.getPage(); gs`^~iD]m
users = result.getContent(); ~%y\@x7I
return SUCCESS; Pg^h,2h
} }X$l\pm
h(xP_Svj>
/** [@{0o+.]'H
* @return Returns the page. oEzDMImJ5
*/ e ^e$mtI
public Page getPage(){ MV+i{]
return page; 3;$bS<>
} PDw{R]V+
BSXdvI1y
/** 4/wwn6I}G
* @return Returns the users. R]b! $6Lt
*/ WPY8C3XO
publicList getUsers(){ #*%fu
return users; 17py).\
} x3p9GAd#
ER|!KtCSM
/** aqQ o,5U>
* @param page /jrY%C
* The page to set. Etmo78e
*/ UR>_)*
publicvoid setPage(Page page){ sp8[cO=
this.page = page; 0B3 QVbp'
} T_L6 t66I
!p%@Deu
/** F+j O*F2h
* @param users fuSq ={]
* The users to set. /GsrGX8
*/ ;9rTE|n
publicvoid setUsers(List users){ lL2-.!]R
this.users = users; ~Q!~ eTw
} B!q?_[k,
`
py}99G
/** d 7i#w
#
* @param userService rycJyiw<-
* The userService to set. &X w`T9<
*/ %F$N#YG
publicvoid setUserService(UserService userService){ J%r7<y\
this.userService = userService; d)*(KhYie@
} _'*DT=H'U
} 2oNV=b[
u
2lXd'
+#v4B?NR
|[wyc!nY).
w~v<v&
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, <;KRj85"j
u[`v&e
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 iwz`
x
}=pOiILvD
么只需要: ]IXAucI]
java代码: S1C^+Sla]
0}-#b7eR
RdkU2Y}V
<?xml version="1.0"?> C5B=NAc
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork Dh8(HiXf:
-M`D>
1.0//EN" "http://www.opensymphony.com/xwork/xwork- CveWl$T12
lQr6;D}+
1.0.dtd"> -RCv7U`
!d|8'^gc
<xwork> x[}06k'
E8;TLk4\
<package name="user" extends="webwork- *K!7R2Rat
M5rwoyn
interceptors"> Q2R-z^pd
H:E5xz3VQ
<!-- The default interceptor stack name ris;Iu^v0
xc*!W*04
--> u
S(@?m$
<default-interceptor-ref [#zE.
TW
JB'qiuhab
name="myDefaultWebStack"/> <"NyC?b+G
?k
w/S4
<action name="listUser" bQ=s8'
0Ts!(b]B
class="com.adt.action.user.ListUser"> s9:%s*$u
<param _}z_yu#jY
ox
JGJ
name="page.everyPage">10</param> |%3O)B
<result hqWPf
]g7HEB.Y
name="success">/user/user_list.jsp</result> cCYl$Ms kZ
</action> xrX?ZJ
Dwk$CJb3-
</package> /\TlO.B=
rN'.&;Y5
</xwork> 8q{1E];:q
${CYDD"mdy
%,Q;<axzi
Yg|l?d"
$KH@,;Xz
wC(XRqlE
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 "h`54}0
#
s,Y%
Bce
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 6BR\iZ
u[:
P
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 U!.~XT=
0~:eSWz=
M@5KoMsB9
+0dQORo
O'@m4@L
我写的一个用于分页的类,用了泛型了,hoho 0\ZaMu #
wFn@\3%l`
java代码: AE]i
V {p
)fy<P;g
~t$mw,
package com.intokr.util; A&;EV#]ge
mC%%)F'Zf
import java.util.List; <?nB,U
+i_'gDy$
/** %h3L
* 用于分页的类<br> k>$FT`
* 可以用于传递查询的结果也可以用于传送查询的参数<br> EI%M
Azj}
* = ]WW'~
* @version 0.01 @-}D7?
* @author cheng $8EV,9^U
*/ A4}JZi6@
public class Paginator<E> { IsWcz+1n
privateint count = 0; // 总记录数 ^#}dPGm
privateint p = 1; // 页编号 [U%.Gi
privateint num = 20; // 每页的记录数 rO5u~"v]
privateList<E> results = null; // 结果 1mY+0
0I(uddG3
/** ntDRlX
* 结果总数 %GNUnr$
*/ Z={D0`
publicint getCount(){ [..,(
return count; xcAF
} V@LN
1|
`WP@ZSC6
publicvoid setCount(int count){ 0,;E.Py?.
this.count = count; d*]Dv,#X
} d'x<-l9
xYT#!K1*
/** &e/@yu)x,
* 本结果所在的页码,从1开始 AB/,S
* FGV}5L
* @return Returns the pageNo. ',L{CQA?c
*/ :5$xh
publicint getP(){ )[e%wPu4e
return p; Z TN:|IKT
} y21)~
L7i}Ga!8
/** 16a_GwfM
* if(p<=0) p=1 E\
K
* E`A<]dAoK
* @param p L"Qh_+
*/ i5ajM,i/K
publicvoid setP(int p){ P@^z:RS*{
if(p <= 0) ~uP
r]#
p = 1; 2U=/<3;u
this.p = p; ^#<:<X6
} g,A.Y,})
[K"U_b}w
/** e6tH/`Uln
* 每页记录数量 I
rtF4ia.
*/ yS1b,cxz
publicint getNum(){ HA$^ *qn
return num; zz7Y/653
} 4iYgs-,
%RCl+hOP.h
/** o(B<!ji~'
* if(num<1) num=1 s_S<gR
*/ NqQM!B]
publicvoid setNum(int num){ owfp^hla
if(num < 1) B2ek&<I7N
num = 1; g:G%Ei~sF
this.num = num; "N?%mCPI
} # i`A4D
%igFHh?
/** GInZ53cQ
* 获得总页数 *F26}q
*/ .g6PrhzFbk
publicint getPageNum(){ Pg!;o=
{M
return(count - 1) / num + 1; n"^/UQ|#j
} CT$& zEIm
h|(ZXCH
/** 1YF+(fk
* 获得本页的开始编号,为 (p-1)*num+1 ?.rH;:9To
*/ ,7n;|1`
publicint getStart(){ >z fq*_
return(p - 1) * num + 1; s=\LewF1<
} [H6X2yjj|
kg/+vJ
/** xA[Wb'
* @return Returns the results. FR@PhMUS
*/ )[@YHE5g
publicList<E> getResults(){ !s#'pTZk4
return results; s2(w#n)
} t%]^5<+X58
rL!_&|
public void setResults(List<E> results){ 78^UgO/
this.results = results; []2$rJZD9
} 4Vb}i[</
j#Ky0+@V
public String toString(){ z*NC?\
StringBuilder buff = new StringBuilder 3<e(@W}n-M
p]1yd;Jt
(); xN{"%>Mx
buff.append("{"); c {f:5 p
buff.append("count:").append(count); d'lr:=GQ
buff.append(",p:").append(p); 7\\~xSXh
buff.append(",nump:").append(num); ex@,F,u>o
buff.append(",results:").append E1U 4v&P
A}t&-
(results); 6oTbn{=UUq
buff.append("}"); %h/#^esi
return buff.toString(); ^\7 x5gO
} 2$SofG6D}
]RJb;
} Oet#wp/I
1Rb XM n
!yV,|)y5F