Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 O{7#Xj
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 V51kX{S
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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 _1Ne+"V
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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 $v e$Sq
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分页支持类: \T<F#a
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java代码: 5`Uzx u
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package com.javaeye.common.util; p}/D{|xO
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import java.util.List; <&O*'
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publicclass PaginationSupport { O\Z!7UQ$
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publicfinalstaticint PAGESIZE = 30; B^zg#x#8
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privateint pageSize = PAGESIZE; P_8!Gp
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privateList items; )8}k.t>'s
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privateint totalCount; F:jtzy"
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privateint[] indexes = newint[0]; %Ny1H/@Q1+
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privateint startIndex = 0; 7F~g A74h
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public PaginationSupport(List items, int /k RCCs8t}
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totalCount){ <
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setPageSize(PAGESIZE); wmXI8'~F&
setTotalCount(totalCount);
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setItems(items); u(f;4`
setStartIndex(0); +|pYu<OY
} gae=+@z
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public PaginationSupport(List items, int ZPq.|6&
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totalCount, int startIndex){ p8YOow7)
setPageSize(PAGESIZE); q{b-2k
setTotalCount(totalCount); Lr6C@pI
setItems(items); 6biR5&Y5U&
setStartIndex(startIndex); 2$!,$J-<Y
} es%py~m)
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public PaginationSupport(List items, int }''0N1,/
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totalCount, int pageSize, int startIndex){ :5T=y @
setPageSize(pageSize); ^*B@=
setTotalCount(totalCount); X !0 7QKs
setItems(items); F Qk
setStartIndex(startIndex); S'ms>ZENC
} <u0}&/
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publicList getItems(){ di9OQ*6a7
return items; ru`U/6n
} 9h)8Mq+M
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publicvoid setItems(List items){ 3ZyvX]@_
this.items = items; g`C8ouy
} W_ Hoa*~
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publicint getPageSize(){ CH|cK8q
return pageSize; D2gyn-]\
} um_J%v6ER
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publicvoid setPageSize(int pageSize){ !io1~GpKS
this.pageSize = pageSize; Jq? zr]"A
} a'Zw^g
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publicint getTotalCount(){ HyKA+7}
return totalCount; .q4$)8[Pg
} 9Hb|$/FD
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publicvoid setTotalCount(int totalCount){ p>3QW3<
if(totalCount > 0){ a;-%C{S9r
this.totalCount = totalCount; I\c7V~^hnG
int count = totalCount / ONy\/lu|
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pageSize; $Zw+"AA
if(totalCount % pageSize > 0) WwtVuc|
count++; wpi$-i`
indexes = newint[count]; f/IQ2yT-:D
for(int i = 0; i < count; i++){ f5un7,m
indexes = pageSize * }YM\IPsPu
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} d]^m^
}else{ _~C1M&b(X3
this.totalCount = 0; *!*%~h8V
} XE2rx2k
} .oTS7rYw
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publicint[] getIndexes(){ L$s ENOm
return indexes; ) )FLM^dj
} J-uQF|
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publicvoid setIndexes(int[] indexes){ l`A&LQ[
this.indexes = indexes; 4E2/?3D
} |mbD q\U
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publicint getStartIndex(){ enQW;N1_M
return startIndex; a8ouk7G
} 6oZHSjC*
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publicvoid setStartIndex(int startIndex){ XOI"BLd
if(totalCount <= 0) Kn= EDtg
this.startIndex = 0; .j^BWr
elseif(startIndex >= totalCount) T{m) = (q
this.startIndex = indexes $0un`&W
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[indexes.length - 1]; 8Lx1XbwK
elseif(startIndex < 0) "$o>_+U
this.startIndex = 0; qnWM %k
else{ -OU{99$aS
this.startIndex = indexes o,c}L9nvt
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[startIndex / pageSize]; 'kY/=*=Q
} /
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} Meep
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publicint getNextIndex(){ zn&ZXFgN
int nextIndex = getStartIndex() + w%X@os}E
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pageSize; WcY_w`*L
if(nextIndex >= totalCount) j|&D(]W/
return getStartIndex(); zy"k b
else Xy!NBh7I
return nextIndex; V.qH&FJ=l
} lz<'
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publicint getPreviousIndex(){ (jj`}Qe3U
int previousIndex = getStartIndex() - <Z.{q Zd
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pageSize; t1J3'lS
if(previousIndex < 0) i\b^}m8c.N
return0; }
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else jn(!6\n"
return previousIndex; $cJ fdE
} ~"J1@<
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} c(2?./\|
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抽象业务类 +L.D3
java代码: K?!W9lUq
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/** Y~{<Hs
* Created on 2005-7-12 %g@\SR.
*/ DC1.f(cdR
package com.javaeye.common.business; I%Yq86
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import java.io.Serializable; qGMU>J.;c
import java.util.List; Xa#.GrH6
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import org.hibernate.Criteria; UQ;2g\([
import org.hibernate.HibernateException; JA9NTu(
import org.hibernate.Session; jXALL8[c
import org.hibernate.criterion.DetachedCriteria; s5mJ
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import org.hibernate.criterion.Projections;
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import *c/V('D/
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org.springframework.orm.hibernate3.HibernateCallback; $MwBt
import fmQif]J;;
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org.springframework.orm.hibernate3.support.HibernateDaoS hE`d@
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upport; >bQOpGy}l
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import com.javaeye.common.util.PaginationSupport; \mJR^t
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public abstract class AbstractManager extends D86F5HT}}
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HibernateDaoSupport { YsVKdh
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privateboolean cacheQueries = false; HK<S|6B7V
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privateString queryCacheRegion; pt3)yj&XE
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publicvoid setCacheQueries(boolean $/g`{OI]K
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cacheQueries){ 8,[ *BgeX
this.cacheQueries = cacheQueries; .JB1#&B+
} F*Hovxez
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publicvoid setQueryCacheRegion(String H!X*29nX
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queryCacheRegion){ Te?PYV-
this.queryCacheRegion = &-Wt!X 3
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queryCacheRegion; lt:&lIW,3
} N}7b^0k
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publicvoid save(finalObject entity){ u?MhK#Mr
getHibernateTemplate().save(entity); Hf_
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} sn^ 3xAF
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publicvoid persist(finalObject entity){ ~Y*.cGA
getHibernateTemplate().save(entity); Ank_;jo
} ;y@zvec4
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publicvoid update(finalObject entity){ m,q)lbRl
getHibernateTemplate().update(entity); N5=}0s]e
} ^mFsrw
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publicvoid delete(finalObject entity){ L/WRVc6
getHibernateTemplate().delete(entity); iM:-750n/
} z(^dwMw}
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publicObject load(finalClass entity, NopfL
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finalSerializable id){ Viw,YkC
return getHibernateTemplate().load <b_K*]Z
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(entity, id); F-ofR]|)>
} 4f8XO"k7t=
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publicObject get(finalClass entity, b`S9#`
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finalSerializable id){ /c-k{5mH%
return getHibernateTemplate().get L?0IUGY
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(entity, id); <[}zw!z
} yY49JZ
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publicList findAll(finalClass entity){ G,Eh8HboK
return getHibernateTemplate().find("from F^!O\8PFd
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" + entity.getName());
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} <_eEpG}9
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publicList findByNamedQuery(finalString L1Yj9i
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namedQuery){ 1'TS!/ll];
return getHibernateTemplate tq'hiS(b
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().findByNamedQuery(namedQuery); fQ!W)>mi
}
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publicList findByNamedQuery(finalString query, 4,X CbcC
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finalObject parameter){ _]Ob)RUVH
return getHibernateTemplate qyKR]%yzi
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().findByNamedQuery(query, parameter); nC??exc
} eUCBQK
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publicList findByNamedQuery(finalString query, Q$`uZ
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finalObject[] parameters){ MzKl=G
return getHibernateTemplate 4A(h'(^7A
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().findByNamedQuery(query, parameters); 5-({z%:P
} a+k3wzJ
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publicList find(finalString query){ .T(vGiU
return getHibernateTemplate().find -:45Q{u/
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(query); xmC5uT6L3M
} N z=P1&G'
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publicList find(finalString query, finalObject KY%qzq,n
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parameter){ Ow5VBw(
return getHibernateTemplate().find ?g@X+!RB
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(query, parameter); bvhV
} !e
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public PaginationSupport findPageByCriteria x.|sCqx
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(final DetachedCriteria detachedCriteria){ awQGu,<N
return findPageByCriteria z `\KQx
j8^#698X
(detachedCriteria, PaginationSupport.PAGESIZE, 0); t*Z5{
} b~)2`l
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public PaginationSupport findPageByCriteria a7u*d`3X=
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(final DetachedCriteria detachedCriteria, finalint +`B^D
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startIndex){ {dE(.Z?]!#
return findPageByCriteria RK$(
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(detachedCriteria, PaginationSupport.PAGESIZE, 7aPA+gA/
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startIndex); <)sL8G9Y
} *(]ZdB_2
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public PaginationSupport findPageByCriteria oGg<s3;UND
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(final DetachedCriteria detachedCriteria, finalint L
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pageSize, i$6a0'@U
finalint startIndex){ w6Mv%ZO_
return(PaginationSupport) TMsCl6dB
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getHibernateTemplate().execute(new HibernateCallback(){ itiSZL,
publicObject doInHibernate |_+l D|'
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(Session session)throws HibernateException { #a
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Criteria criteria = [4dX[
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detachedCriteria.getExecutableCriteria(session); ;}ThBb3
int totalCount = z" ?WT$
@ uQ *$
((Integer) criteria.setProjection(Projections.rowCount p-DHTX
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()).uniqueResult()).intValue(); 8.IenU9
criteria.setProjection ty%,T.@e
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(null); >+!Ef
List items = EaL>~:j
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criteria.setFirstResult(startIndex).setMaxResults Pl`Nniy
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(pageSize).list(); eC6wrpZO
PaginationSupport ps = pY\=f0]
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new PaginationSupport(items, totalCount, pageSize, @*=5a(#
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startIndex); yO7#n0q
return ps; Rs"G8Q9Q
} n)35-?R/M
}, true); 'W("s
} %yl17:h#
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public List findAllByCriteria(final Y)(yw \&v
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DetachedCriteria detachedCriteria){ ]-SJ";aU
return(List) getHibernateTemplate +~y>22Zfg
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().execute(new HibernateCallback(){ )_4()#3
publicObject doInHibernate 0plX"NU
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(Session session)throws HibernateException { fl2XI=[v4
Criteria criteria = ga S}>?qk
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detachedCriteria.getExecutableCriteria(session); \ptjnwC^O
return criteria.list(); x5/&,&m`%
} 0O*kC43E_
}, true); p7r/`_'|
} qn |~YXn
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public int getCountByCriteria(final ` QW=<Le?
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DetachedCriteria detachedCriteria){ >&7^yXS
Integer count = (Integer) kl9~obX
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getHibernateTemplate().execute(new HibernateCallback(){ `c-omNu
publicObject doInHibernate 'ShK7j$
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(Session session)throws HibernateException { ev_' .t'
Criteria criteria = Q[|*P ] w
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detachedCriteria.getExecutableCriteria(session); ;G3?Sa7+
return s2 :Vm\
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criteria.setProjection(Projections.rowCount &"hEKIqL
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()).uniqueResult(); n5IQKYrg
} VRD^> Gi
}, true); MHye!T6fO\
return count.intValue(); qE]e+S?57a
} $z 5kA9
} ha 2=O
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用户在web层构造查询条件detachedCriteria,和可选的 >'.: Acn
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 4i+%~X@p
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PaginationSupport的实例ps。 #k`gm)|
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ps.getItems()得到已分页好的结果集 q(~|roKA(
ps.getIndexes()得到分页索引的数组 jI H^
ps.getTotalCount()得到总结果数 uI%7jA~@
ps.getStartIndex()当前分页索引 BHZhdm@),
ps.getNextIndex()下一页索引 ;YW@ 3F-h
ps.getPreviousIndex()上一页索引 VYO1qj
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 =6Gn?
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 DrC"M*$!
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一下代码重构了。 af9KtX+
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我把原本我的做法也提供出来供大家讨论吧: )c'E9ZuZ>d
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首先,为了实现分页查询,我封装了一个Page类: W\;|mEEu
java代码: ACZK]~Y'N*
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/*Created on 2005-4-14*/ J|%bRLX@>
package org.flyware.util.page; '\xE56v)F
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/** B.~]
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* @author Joa fmc\Li
* 5$N#=i`V
*/ p:W]
publicclass Page { G'PZ=+!XO/
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/** imply if the page has previous page */ _*Z3,*~"X
privateboolean hasPrePage; e6J^J&`|4
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/** imply if the page has next page */ -57~7
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privateboolean hasNextPage; 9:-7.^`P
}f?[m&<
/** the number of every page */ E]GbLU;TH
privateint everyPage; A~<!@`NjB
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/** the total page number */ BK6
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privateint totalPage; } e+`Kxy
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/** the number of current page */ DZnqCu"J
privateint currentPage; _ezRE"F5
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/** the begin index of the records by the current qq)}GK8K&
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query */ u;c
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privateint beginIndex; i$PO#}
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/** The default constructor */ cy;i1#1rO
public Page(){ CEc(2q+%i
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} -`* 'p i
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/** construct the page by everyPage S)j(%g
* @param everyPage :-JryiI
* */ <<A#4!f
public Page(int everyPage){ n-l_PhPQ`
this.everyPage = everyPage; CW?Z\
} =&$z
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/** The whole constructor */ c$7~EP
public Page(boolean hasPrePage, boolean hasNextPage, gK({InOP
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}YFM40H
int everyPage, int totalPage, Mh5>
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int currentPage, int beginIndex){ Q[rZ1z
this.hasPrePage = hasPrePage; UF#!6"C@
this.hasNextPage = hasNextPage; ID,_0b
this.everyPage = everyPage; XC^*z[#4{
this.totalPage = totalPage;
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this.currentPage = currentPage; L8Tm8)
this.beginIndex = beginIndex; BOG.[?yx
} _avf%OS
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/** _OuNX.yrG
* @return M.- {->
* Returns the beginIndex. ?dCwo;~
*/ PRaVe,5a
publicint getBeginIndex(){ n{sk
return beginIndex; p8%qU>~+4
} n-" (~
ka\{?:r,8
/** W3/bM>1
* @param beginIndex $KGMAg/H
* The beginIndex to set. fPUr O
*/ VYkh@j
publicvoid setBeginIndex(int beginIndex){ Z,E$4Z
this.beginIndex = beginIndex; C:5-h(#
} Fw\Z[nh
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/** 4hwb]
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* @return J#F5by%8
* Returns the currentPage. *0!p_Hco
*/ Hf]:mhH
publicint getCurrentPage(){ 9AX}V6\+
return currentPage; 8lYA6A
} wPjq
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/** %N<5ST>(
* @param currentPage hDJG.,r
* The currentPage to set. bkDVW
*/ :QGo
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publicvoid setCurrentPage(int currentPage){ tSJ#
this.currentPage = currentPage; W?.469yy
} 7UMZs7L$
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/** aM;SE9/U
* @return e>Z&0lV:
* Returns the everyPage. nWIZ0Nde'
*/ Y|fD)zG_
publicint getEveryPage(){ Nbd4>M<
return everyPage; y&,|+h
} 'lA}E
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/** .s*N1
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* @param everyPage F8?2+w@P
* The everyPage to set. '@.6Rd 8
*/ /x ?@Mn>
publicvoid setEveryPage(int everyPage){ VGeTX 4h
this.everyPage = everyPage; nwKp8mfP
} (6ga*5<
1 #,4P1"
/** rx gSQ+G_
* @return $lf/Mg_H
* Returns the hasNextPage. t2(X
*/ .))jR:{3
publicboolean getHasNextPage(){ 3&^hf^yg
return hasNextPage; 7 mCf*|
} 5:IDl1f5
-eF-r=FR
/** {kk%_q
* @param hasNextPage //2O#Fg{/
* The hasNextPage to set. k;+TN9
*/ h8`On/Ur_8
publicvoid setHasNextPage(boolean hasNextPage){ M=liG+d
this.hasNextPage = hasNextPage; K'Ywv@
} 2j%=o?me^p
wBXa;.
/** M\m:H3[
* @return `CS\"|z
* Returns the hasPrePage. s`bGW1#io
*/ 6~%><C
publicboolean getHasPrePage(){ ?;CIS$$r
return hasPrePage; R QQ'Wg
} D#&9zR86F
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/** =SLG N`m3
* @param hasPrePage '/u|32
* The hasPrePage to set. #MA6eE'R
*/ sWr;%<K
publicvoid setHasPrePage(boolean hasPrePage){ p6<JpW5@_
this.hasPrePage = hasPrePage; (NLw#)?
} D;0>-
r&4Xf#QD6
/** =;0-t\w!
* @return Returns the totalPage. 'r]6 GC8Z$
* Z8$BgP
*/ (uvQ/!
publicint getTotalPage(){ }( F:U#
return totalPage; 9Y.(xp &vw
} @\?ubF
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/** 5VTVx1P[8
* @param totalPage aG
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* The totalPage to set. /(JG\Ut
*/ l{dsm1#W~
publicvoid setTotalPage(int totalPage){ 9?,i+\)qK@
this.totalPage = totalPage; >wh v*@Fr
} OK80-/8HI
"++\6H<
} 00 x-
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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 l'(FM^8jv
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个PageUtil,负责对Page对象进行构造: .gg0rTf=-
java代码: 6U ! P8q
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/*Created on 2005-4-14*/ /*y5W-'d^
package org.flyware.util.page; fG'~@'P~
^ 0YQlT98
import org.apache.commons.logging.Log; >*{k~Y-G
import org.apache.commons.logging.LogFactory; VBL4cU8D
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/** T<0 r,
* @author Joa HQP.7.w7 5
* P'qBqx[
*/ L6_%SGY_iE
publicclass PageUtil { s<{ Hu0K$
V gMgeja
privatestaticfinal Log logger = LogFactory.getLog #Q!Xz2z2
m:h6J''<Z*
(PageUtil.class); o+Jnn"8
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/** nv_v FK
* Use the origin page to create a new page OlCqv-B2&
* @param page eI$V2
* @param totalRecords <9,h!
* @return MG vz-E1e
*/ |;US)B8}*Z
publicstatic Page createPage(Page page, int 7G_<+rn
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totalRecords){ 9PKXQp
return createPage(page.getEveryPage(), {d[Nc,AMb
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page.getCurrentPage(), totalRecords); U&#`
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} VP
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/** eI:[o
* the basic page utils not including exception ? #rXc%F
oY^I|FEOz
handler Yc]V+NxxQ
* @param everyPage K2Abu?
* @param currentPage /7D5I\
* @param totalRecords .JLJ(WM
* @return page *gwaW!=
*/ 44*#qLN
publicstatic Page createPage(int everyPage, int @6G)(NGD
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currentPage, int totalRecords){ /.0K#J:
everyPage = getEveryPage(everyPage); mzK0$y#*o
currentPage = getCurrentPage(currentPage); D-/6RVq0m
int beginIndex = getBeginIndex(everyPage, ;F258/J
u*@R`,Y
currentPage); ! :]_-DX
int totalPage = getTotalPage(everyPage, #$BFTlm|
}eVDe(7_
totalRecords); 3tf_\E+mIi
boolean hasNextPage = hasNextPage(currentPage, ^!S4?<v
,pD sU @
totalPage); `'s_5Ek
boolean hasPrePage = hasPrePage(currentPage); D Yf2V6'
>;4q
returnnew Page(hasPrePage, hasNextPage, .5Y{Yme
everyPage, totalPage, z]N#.utQ
currentPage, U*a#{C7"
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beginIndex); *:H,-@
} jz<}9Kze
.rk5u4yK
privatestaticint getEveryPage(int everyPage){ s-rc0:I
return everyPage == 0 ? 10 : everyPage; }oZ8esZU2
} AF#:*<Ev
ysOf=~1
privatestaticint getCurrentPage(int currentPage){ [nxYfER7
return currentPage == 0 ? 1 : currentPage; ~JT2el2W7p
} 8~O#@hB~3
I]eeV+U8W
privatestaticint getBeginIndex(int everyPage, int x >a h,
{nmu(EP
currentPage){ G{: B'08
return(currentPage - 1) * everyPage; $Xwk8<
} _\d|`3RM
@FIL4sb
privatestaticint getTotalPage(int everyPage, int #[M^Q
h
ywp_,j9F
totalRecords){ ,Sgo_bC/|
int totalPage = 0; d=bKNA90
KuwhA-IL
if(totalRecords % everyPage == 0) :-d#kU
totalPage = totalRecords / everyPage; legWY)4D;
else b~&cYk'
totalPage = totalRecords / everyPage + 1 ; .fzyA5@l
7Y@]o=DIc
return totalPage; FL \pgbI
} ^rfR<Q`
UUfM7gq
privatestaticboolean hasPrePage(int currentPage){ 4|_xz;i
return currentPage == 1 ? false : true; :? B4q#]N
} *N$XQ{o
u;9iuc`*
privatestaticboolean hasNextPage(int currentPage, c{Z
"'t7
0\!Bh^++1
int totalPage){ i{EQjZ
return currentPage == totalPage || totalPage == ]@9W19=P!P
A]m*~Vj]
0 ? false : true; liYsUmjZ=
} +>C26Q
Y[L,rc/j
|5(un#
} o+hp#e
{BlTLAKm
R^`}DlHX
LIG@`
m)66g]F+
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。 8WDL.IO
}BS
EK<W
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 huv|l6
D>jtz2y=D
做法如下: Ch?yk^cY
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 eHUyV@
{s@!N
的信息,和一个结果集List: Ydsnu
java代码: Q#yHH]U)X
mH;t)dT
N_:!uR
/*Created on 2005-6-13*/ Lfx a^0
package com.adt.bo; e6'0g=Y#
e;=R8i
import java.util.List; ^kK")+K
pWzYC@_W
import org.flyware.util.page.Page; a`yCPnB(
4;~xRg;u&*
/** ww
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* @author Joa DOtz
*/ H$?MPA-c
publicclass Result { W:<2" &7
g&/lyQ+G
private Page page; "n3n-Y#'
#vK99S2
private List content; EIzTbW{p
e?(4lD)d
/** O~8jz
* The default constructor ){/n7*#Th%
*/ t_I-6`8o]
public Result(){ nZj&Ma7R
super(); pD P*
3
} 6$PQ$
=^M Q 4
/** b/.EA'/
* The constructor using fields =Cf@!wZ^
* SKf;Fe
* @param page ^K`PYai
* @param content L7 FFa:#
*/ &:d`Pik6
public Result(Page page, List content){ zLr:zf l
this.page = page; ~yN>9f U
this.content = content; ]p(es,[
} CA|W4f}
/!&eP3^
/** G@rh/b<$
* @return Returns the content. [D|Uwq
*/ M&Q&be84
publicList getContent(){ tWZ8(E$
return content; ow (YgM>t
} lnl>!z
8}oe))b
/** -{L 7%j|R
* @return Returns the page. r8y,$Mv<)0
*/ 'h&>K,U?5
public Page getPage(){ f
4K)Z
e
return page; +tkm,>s
} #?M[Q:
MYJDfI
/** j5hQ;~Fa|
* @param content )@B!
* The content to set. W:f )#'
*/ Tpnwwx[]:|
public void setContent(List content){ |&S^L}V.C
this.content = content; h{]0
H'g
} qoQ,3&<
wMm+E "}W
/** &_QD1 TT
* @param page sAX4giaLD
* The page to set. ]*DIn1C^
*/ &z\?A2Mw%
publicvoid setPage(Page page){ Ki:98a$
this.page = page; OpOR!
} 5=<fJXf5y
} Jk<b#SZ[b
v>hc\H1P
4[r:DM|8
bA"*^"^
7'.6/U
2. 编写业务逻辑接口,并实现它(UserManager, A9HgABhax
/#x0?d{5
UserManagerImpl) U&+lw=
java代码: FGMYpapc~
#s=\
wXeJjE%j:3
/*Created on 2005-7-15*/ =6'D/| 3
package com.adt.service; $xcU*?=K
O[}2
import net.sf.hibernate.HibernateException; >\Iy <M
~:="o/wo
import org.flyware.util.page.Page; >tkU+$;-
>Co@K^'
import com.adt.bo.Result; rt! lc-g%/
zW95qxXg
/** 65c#he[_Y
* @author Joa u"q!p5P%q
*/ Qz A)HDQ
publicinterface UserManager { AdF[>Wv
TY#pj
public Result listUser(Page page)throws qy!pD
R;
)Vy}oFT\
HibernateException; 6:bvq?5a5
xtS0D^
} nza^<DlS
SP|Dz,o
V+y:!t`
}?d
l.=eq
1z8AK"8
java代码: 0j-;4>p
4mWT"T-8
q'[yYPDX5x
/*Created on 2005-7-15*/ :e4[isI
package com.adt.service.impl; -QydUr/(o
5~omZ,qe
import java.util.List; J$Ba*`~!!
4[LzjC
import net.sf.hibernate.HibernateException; %lK]m`(
7w|4BRL
import org.flyware.util.page.Page; FU(s jB
import org.flyware.util.page.PageUtil; #w]:<R^
ZsDn`8
import com.adt.bo.Result; w W;!L=j
import com.adt.dao.UserDAO; )Chx,pcx<
import com.adt.exception.ObjectNotFoundException; /aMeKM[L`
import com.adt.service.UserManager; T CO^9RP<
"IsDL^)A9
/** NB/ wJ3 F
* @author Joa T$xY]hqr
*/ ki_Py5
publicclass UserManagerImpl implements UserManager { 852Bh'u_
Qte'f+
private UserDAO userDAO; cd*F;h
,W<mz7Z(@
/** A?OaP
* @param userDAO The userDAO to set. GfT`>M?QGK
*/ bX]$S 5c_u
publicvoid setUserDAO(UserDAO userDAO){ U7cGr\eUu
this.userDAO = userDAO; R*psL&N
} -Z%B9ql'
9/S-=VOe.t
/* (non-Javadoc) U_c9T> =
* @see com.adt.service.UserManager#listUser s@bo df&
X5D}<J2"
(org.flyware.util.page.Page) H`ZUI8-
*/ fNaS?tV)
public Result listUser(Page page)throws ,a,coeL
E%C02sI
HibernateException, ObjectNotFoundException { zpd Z.
int totalRecords = userDAO.getUserCount(); \XlT
if(totalRecords == 0) }Pe0zx.Ge
throw new ObjectNotFoundException {oN7I'>
i5 0^%,
("userNotExist"); }M9L,O*^
page = PageUtil.createPage(page, totalRecords); {e8.E<f-
List users = userDAO.getUserByPage(page); +3D3[.n
returnnew Result(page, users); s4c2
} _[.3I1kG
PYz^9Ud 6g
} ra k@oW]
qS|t7*
sIh,@b
7*r7Q'
$n?@zd@53
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ,;yiV<AD
HGpj(U:`c
询,接下来编写UserDAO的代码: "(rG5z3P
3. UserDAO 和 UserDAOImpl: !'^gqaF+
java代码: J@c)SK%2h
\{[Gdj`
`8%2F}x}qD
/*Created on 2005-7-15*/ ;u0MY
package com.adt.dao; $k|k 5cP8x
}l>0m
import java.util.List; 1x#Z}XG
hqVFb.6[
import org.flyware.util.page.Page; H`;q@
Fh4kd>1D
import net.sf.hibernate.HibernateException; a$SGFA}V
14p <0BG
/** fWywegh
* @author Joa 0x\bDWZ_
*/ TPrqb
publicinterface UserDAO extends BaseDAO { Gt^Fj&^
OXuBtW*,z+
publicList getUserByName(String name)throws q8{)27f,
C-abc+/
HibernateException; ;X
]+r$_
K$dSg1t
publicint getUserCount()throws HibernateException; |A#pG^
@e_ bG@
publicList getUserByPage(Page page)throws lXS.,#lp
T8,?\7)S9
HibernateException; !giL~}j(R
O!(M:.
} Ph'P<h:V
kw>W5tNpf:
~4\J}Kn
|T}Q~
3U0>Y%m| ,
java代码: 3%G>TB
0m^(|=N-
f\}fUg2
/*Created on 2005-7-15*/ $]eITyC`P
package com.adt.dao.impl; Gvk)H$ni
QQUYWC
import java.util.List; /[iqga=
^-9g_5
import org.flyware.util.page.Page; lU0'5!3R,
+wU9d8W
import net.sf.hibernate.HibernateException; RHdcRojF
import net.sf.hibernate.Query; )B86
-lL(:drn
import com.adt.dao.UserDAO; 0Z{f!MOh
RjY(MSc
/** .mzy?!w0q
* @author Joa P5Y:c@u2
*/ VL5GX(
public class UserDAOImpl extends BaseDAOHibernateImpl o.ntzN
P".CZyI-i
implements UserDAO { TzT(aWP"
v"VpE`z1#
/* (non-Javadoc) }j^asuf~c
* @see com.adt.dao.UserDAO#getUserByName ?CgqHmf\\(
J|-X?V;ZW
(java.lang.String) x78`dX
*/ *UVo>;
publicList getUserByName(String name)throws "NY[&S
EIqe|a+
HibernateException { u:Fa1 !4JR
String querySentence = "FROM user in class E)l0`83~^
Nr?Z[6O|
com.adt.po.User WHERE user.name=:name"; zrqQcnx9(m
Query query = getSession().createQuery M<R3Jz T
);o2eV
(querySentence); PT7-_r
query.setParameter("name", name); *w>dT
return query.list(); E-Nc|A
} Cku#[?G
{k4)f ad\
/* (non-Javadoc) &DQyJJ`k
* @see com.adt.dao.UserDAO#getUserCount() w\o?p.drp=
*/ \wR $_X&
publicint getUserCount()throws HibernateException { !2-f%x]tO
int count = 0; _?"P<3/iF
String querySentence = "SELECT count(*) FROM lxIoP
s9R#rwIc
user in class com.adt.po.User"; Id6H~;
Query query = getSession().createQuery OIpkXM
zPzy0lx
(querySentence); &\8qN_`
count = ((Integer)query.iterate().next '
U]\]Wp
x3j)'`=15
()).intValue(); J:<mq5[
return count; .E H&GX
} }^!8I7J.
rucgav
/* (non-Javadoc) @ev"{dY
* @see com.adt.dao.UserDAO#getUserByPage I$.HG]
w$Zi'+&*
(org.flyware.util.page.Page) vGe];
*/ 0_F6t-
publicList getUserByPage(Page page)throws b.mcP@
Ass :
HibernateException { 2a=3->D&
String querySentence = "FROM user in class usj:I`>
>Q5et1c
com.adt.po.User"; ?VUU[h8"v5
Query query = getSession().createQuery BbU%p
b`a4SfbQS
(querySentence); @|AHTf!
query.setFirstResult(page.getBeginIndex()) - BQoNEh
.setMaxResults(page.getEveryPage()); Rcg q7W
return query.list(); [{iPosQWj
} w ]8+
OP
8DAHaS;
} <v&L90+s\;
HQtR;[1
52X[{
dY=]ES}`
o#GZ|9IL
至此,一个完整的分页程序完成。前台的只需要调用 Qt-7jmZw1
5&59IA%S
userManager.listUser(page)即可得到一个Page对象和结果集对象 Z^tTR]u\$
*Ubsa9'fS
的综合体,而传入的参数page对象则可以由前台传入,如果用 Y~E
8z
`_YXU
webwork,甚至可以直接在配置文件中指定。 <{ZDD]UGs0
ltQo_k
下面给出一个webwork调用示例: i}u,_
}
java代码: (AYzN3
?D
b+=@;0p*6B
7:[u.cd
/*Created on 2005-6-17*/ s#Os?Q?
package com.adt.action.user; s2Z'_rT
#:B14E
import java.util.List; )RUx
_3Kow{y\
import org.apache.commons.logging.Log; Qy4eDv5
import org.apache.commons.logging.LogFactory; eELLnU{"
import org.flyware.util.page.Page; d-X6yRjnj
4d x4hBd
import com.adt.bo.Result; M Ewa^
import com.adt.service.UserService; |Y-{)5/5}
import com.opensymphony.xwork.Action; >W?i+,g
g=#Cc(
q
/** 4{PN9i
E
* @author Joa O)N$nBnp
*/ .1{:Q1"S
publicclass ListUser implementsAction{ "A(D}~i
PiwMl)E|!
privatestaticfinal Log logger = LogFactory.getLog |WkWZZ^
u~O9"-m !V
(ListUser.class); ;AH8/M B9
.-Z=Aa>
private UserService userService; ZVX1@p
B4
k5IS
private Page page; b=L4A,w~a
Z= +Tw!wR>
privateList users; @23?II$=@
I K9plsd*
/* ,=a+;D]'
* (non-Javadoc) ]F{F+r
* #]rfKHW9
* @see com.opensymphony.xwork.Action#execute() "xI70c{
*/ QLm#7ms*y
publicString execute()throwsException{ ,+P2B%2c
Result result = userService.listUser(page); 'G1~
A +
page = result.getPage(); yac4\%ze
users = result.getContent(); :$=]*54`T
return SUCCESS; + *W%4e
} MZrLLnl6\
dz6&TdEl
/** */_$' /qV
* @return Returns the page. `w8Ejm?n
*/ G1
K@Ir<
public Page getPage(){ a
S;z
YD
return page; T^ )\
} m$.7) 24
.DR*MQI9
/** v) j3YhY
* @return Returns the users. M!`&Z9N
*/ 7VIfRN{5n
publicList getUsers(){ u<U8LR=)V5
return users; !#Pr'm/,mu
} ?vBMx _0
*ZkOZ
/** RRb>]oD
* @param page H73 r3BH
* The page to set. Pk3b#$+E
*/ ^/ff)'.J
publicvoid setPage(Page page){ :@b=;
this.page = page; t`-
[
} j6d{r\!$4
\zJb}NbnT
/** %$<v:eMAs
* @param users XI'.L ~
* The users to set. tXCgRU
*/ %oOSmt
publicvoid setUsers(List users){ v t_lM
this.users = users; {,=U]^A
} ,7I
"]bOpk T
/** $ba*=/{[q
* @param userService >~l^E!<i-u
* The userService to set. m;J'y2h =$
*/ OI,F,4e
publicvoid setUserService(UserService userService){ j;<s!A#
this.userService = userService; ]pWn%aGv*Y
} vX?C9Fr 2
} d"=)=hm!
)GfL?'Z
2U`!0~pod
^v&"{2
F]L96&
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, ?BX}0RWMh7
m f\tMik<
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 nKmf#
L=@8Zi!2<
么只需要: )+Yu7=S
java代码: |&MOus#v
z.!u<hy(
pwvmb\
<?xml version="1.0"?> ,z01*Yx
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork x21XzGLY|}
GMY[Gd
1.0//EN" "http://www.opensymphony.com/xwork/xwork- <Zo{D |hW
n0FzDQt26
1.0.dtd"> ><C9PS@
;>%wf3e
<xwork> gSHN,8.
`
,:{+-v(
<package name="user" extends="webwork- mLV0J '
(~NR."s;
interceptors"> OD~yIV
dn&484
<!-- The default interceptor stack name oT!i}TW?o
3fUiYI|&7
--> ~Zw37C9J
<default-interceptor-ref !iL6 /
y[/:?O}g4
name="myDefaultWebStack"/> WQ9VcCY
Ri3*au/Q
<action name="listUser" h^YUu`P
yJ>Bc
class="com.adt.action.user.ListUser"> g'9~T8i& ^
<param v=daafO
,=[r6k<
name="page.everyPage">10</param> y:Ag mr,S
<result Ih[k{p
ltv~Kh
name="success">/user/user_list.jsp</result> ctPT=i60
</action> &"=O!t2
/ <+F/R'=O
</package> }&]T0U`@
tlYB'8bJY
</xwork> N+vsQ!Qz
z2jS(N?J1
xx G>Leml
L=5Y^f'aU
a{Y8hR
Rl
(+TE
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 /2cn`dR,
wauM|/KG
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。 D|2lBU
hP_{$c{4:g
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 i&-g
_z\qtl~3
DG,m;vg+
'8LHX6FXK
Pk6_ 1LV
我写的一个用于分页的类,用了泛型了,hoho paUJq?Af
55Xfu/hQ
java代码: +E+I.}sOB
([ A%>u>h
Y pvFv-
package com.intokr.util; /PpZ6ne~[
>ktekO:H
import java.util.List; 6ZQ$5PY
D 77$aCt
/** P)[QC
* 用于分页的类<br> WHr:M/qD
* 可以用于传递查询的结果也可以用于传送查询的参数<br> N_p^DP
* M8VsU*aU
* @version 0.01 /px`FuJI(
* @author cheng wsj5;(f+
*/ )o;n2T#O
public class Paginator<E> { aW#^@||B
privateint count = 0; // 总记录数 -h 21
privateint p = 1; // 页编号 LAGg(:3f3
privateint num = 20; // 每页的记录数 b~?3HY:t~K
privateList<E> results = null; // 结果 w ; PV
&M
AQPzId*z
/** 6-\C?w
A
* 结果总数 N::.o+1
*/ 'EB5#
publicint getCount(){ b{,vZhP-
return count; j?(@x>HA
} .p'\@@o5
{sUc2vR
publicvoid setCount(int count){ 7 .xejz
this.count = count; ):V)Hrq?x
} YVO~0bX:
XeXK~
/** !/Wv\qm
* 本结果所在的页码,从1开始 S/6I9zOP
* ^3nB2G.ax
* @return Returns the pageNo. nz`"f,
*/ D[(T--LLT
publicint getP(){ nN(Q}bF
return p; ;zo?o t/
} HqA3.<=F,
?e23[
/** h}%yG{'/M=
* if(p<=0) p=1 ; zfBe%Uf
* [jF\"#A
* @param p $I a-go2W
*/ ^Y^5 @x=
publicvoid setP(int p){ NmV][0(BS
if(p <= 0) 9|hPl-.
.W
p = 1; F:-6Htmj
this.p = p; ;W!hl<``d*
} !Op18hP$
Q?Uk%t\hwc
/** #~ [mn_C
* 每页记录数量 <PQ[N[SU
*/ \JGRd8S[
publicint getNum(){ p+R8Mo;I
return num; <$`udP@
} pl.=u0 *
<~Tfi*^+
/** 7@i2Mz/eV
* if(num<1) num=1 [oS.B\Vc
*/ }u~r.=
publicvoid setNum(int num){ y{\(|j
if(num < 1) }{e7wqS$&,
num = 1; G$
Ii
this.num = num;
\4&FW|mx
} Gp))1b';
?[q.1O
/** &?7+8n&+
* 获得总页数 1H,hw
*/ P
C
publicint getPageNum(){ 2n5{H fpY
return(count - 1) / num + 1; :6Sb3w5h
} a<{+
JU5
kx3]A"]>'
/** f%Bm x{Ttq
* 获得本页的开始编号,为 (p-1)*num+1 Hy1f,D
*/ ACxjY2
publicint getStart(){ \6v*c;ZF
return(p - 1) * num + 1; |h%fi-a:
} ZBfB4<M9xS
zXg/.z]
/** qbdv
* @return Returns the results. UkBr4{+aE
*/ ;hp?wb
publicList<E> getResults(){ ppM^&6x^
return results; '^.}5be&
} \)T4NN
&:*|K xX
public void setResults(List<E> results){
y-CVyl
this.results = results; p uLQ_MNV
} as| MB
(
eEkbD"Q
public String toString(){ RJZ4fl
StringBuilder buff = new StringBuilder %O3 r>o=
D*#r
V
P
(); kT6EHuB
buff.append("{"); })}-K7v1+
buff.append("count:").append(count); WD5ulm?91|
buff.append(",p:").append(p); T Jp0^&Q
buff.append(",nump:").append(num); :j0r~*z-
buff.append(",results:").append (s.S
n(E
ur2`.dY>3"
(results); !ZlNPPrq}
buff.append("}"); &za~=+
return buff.toString(); ssC5YtF7X
} tmI2BBv
goV[C]|
} BpKgUwf;C
A PR%ZpG
6?c(ue iL[