Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 DFH6.0UW
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 9E*K44L/V
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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 _^A
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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 `^Sq>R!;
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分页支持类: ?Gu>!7
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java代码: ZOsn,nF
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package com.javaeye.common.util; DN_C7\CoA
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import java.util.List; RlL,eU$CS
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publicclass PaginationSupport { K?I&,t_*R
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publicfinalstaticint PAGESIZE = 30; -L3RzX
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privateint pageSize = PAGESIZE; +Ea XS
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privateList items; )o,0aGo>Of
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privateint totalCount; }Elce}
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privateint[] indexes = newint[0]; ^!tI+F{n{
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privateint startIndex = 0; jzw?V9Ijb
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public PaginationSupport(List items, int VG7#6)sQoK
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totalCount){ AXI:h"so
setPageSize(PAGESIZE); J8'zvH&I
setTotalCount(totalCount); m@?e
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setItems(items); 1r4/McB
setStartIndex(0); S!cXc/H-R
} 1i2O]e!
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public PaginationSupport(List items, int 3S?+G)qKo
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totalCount, int startIndex){ ?^Ux+mVE
setPageSize(PAGESIZE); U0T N8O}Z
setTotalCount(totalCount); R:p,Hav<q
setItems(items); g{(nt5|^l
setStartIndex(startIndex); x~^nlnKVf
} z5/O8}Gz@
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public PaginationSupport(List items, int \]El%j4
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totalCount, int pageSize, int startIndex){ DVH><3FF
setPageSize(pageSize); +.cv,1Vx
setTotalCount(totalCount); m8'1@1d|
setItems(items); 7F~+z7(h
setStartIndex(startIndex); h#nQd=H<g#
} _%B`Y ?I`
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publicList getItems(){ BD+?Ad?
return items; l"8YI sir
} 7L"/4w
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publicvoid setItems(List items){ sxtGl^,mU:
this.items = items; 1L7,x @w
} 5K<C
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publicint getPageSize(){ ?CDq^)T[
return pageSize; q4oZJ -`
} ,,gYU_V
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publicvoid setPageSize(int pageSize){ IgL8u
this.pageSize = pageSize; lla96\R
} "
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publicint getTotalCount(){ jEI L(0_H
return totalCount; yW 3h_08
} 0b'R5I.M
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publicvoid setTotalCount(int totalCount){ r.5F^
if(totalCount > 0){ VXS9E383
this.totalCount = totalCount; 1,,-R*x
int count = totalCount / =UY@,*q:c
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pageSize; yM@cml6Ox
if(totalCount % pageSize > 0) mr? ii
count++; \mloR
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indexes = newint[count]; '>BHwc
for(int i = 0; i < count; i++){
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indexes = pageSize * v]~[~\|a
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} QR4o j
}else{ f`e.c_n(
this.totalCount = 0; >Mn.|:DF]&
} R0[Gfq9M=
} oLoa71Q}
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publicint[] getIndexes(){ 5]E5 V@C
return indexes; ?$Pj[O^hl
} ~m7+^c@,
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publicvoid setIndexes(int[] indexes){ ,U}8(D~:
this.indexes = indexes; R#>E{[9
} "5Mo%cUp
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publicint getStartIndex(){ Qw:j2g2H7
return startIndex; KMV!Hqkk
} O9Aooe4W=
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publicvoid setStartIndex(int startIndex){ r+Y1m\
if(totalCount <= 0) x{E[qH_1Fm
this.startIndex = 0; d<o
elseif(startIndex >= totalCount) &BkNkb 0
this.startIndex = indexes ~gN'";1i
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[indexes.length - 1]; XJ"9D#"a>
elseif(startIndex < 0) V]2Q92
this.startIndex = 0; -84Z8?_
else{ aO1cd_d6x_
this.startIndex = indexes gE1" .qC
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[startIndex / pageSize]; !k:j+h/
} sp%7iNs
} 9YKEME+:
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publicint getNextIndex(){ SzgVvmM}
int nextIndex = getStartIndex() + ctGjqHo
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pageSize; myXV~6R
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if(nextIndex >= totalCount) e(Verd:c
return getStartIndex(); vjpe'zx
else l< Y x
return nextIndex; ~$`b{
} &N EzKf
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publicint getPreviousIndex(){ S<TfvQ\,"@
int previousIndex = getStartIndex() - 4?Io@[7A)
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pageSize; ="`y<J P
if(previousIndex < 0) X^ovP'c2
return0; VaB7)r
else 0pQ>V)
return previousIndex; 5Ai
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} IH5thL@D
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} `f s[C
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抽象业务类 $jHL8r\e7
java代码: SNQ+ XtoO
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/** z"<PveVo
* Created on 2005-7-12 |^ qW
*/ 8]O|$8'"
package com.javaeye.common.business; <^=k~7m
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import java.io.Serializable; JOMZ&c^
import java.util.List; KksbhN{AB
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import org.hibernate.Criteria; [-l^,,E
import org.hibernate.HibernateException; Z1Ms~tch
import org.hibernate.Session; :!%oQQO
import org.hibernate.criterion.DetachedCriteria; X**wRF
import org.hibernate.criterion.Projections; R{T4AZ@,'
import 6c2fqAF>i
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org.springframework.orm.hibernate3.HibernateCallback; \1tce`+
import nP}/#Wy
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org.springframework.orm.hibernate3.support.HibernateDaoS /fX]Yu
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upport; O
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import com.javaeye.common.util.PaginationSupport; <a'j8pw9i
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public abstract class AbstractManager extends m+o>`1>a
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HibernateDaoSupport { m_pK'jc
@FQ@*XD
privateboolean cacheQueries = false; ;>PV]0bOm>
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privateString queryCacheRegion; kr3ZqMfeI
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publicvoid setCacheQueries(boolean u",
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cacheQueries){ 8J)x>6
this.cacheQueries = cacheQueries; O".#B
} S`NH6?/uH
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publicvoid setQueryCacheRegion(String zNBG;\W
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queryCacheRegion){ &=f%(,+
this.queryCacheRegion = KVK@Snn
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queryCacheRegion; m^TkFt<BM
} ;$W|FpR2
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publicvoid save(finalObject entity){ *`dGapd3
getHibernateTemplate().save(entity); [x@iqFO9
} 9{+B lNZ
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publicvoid persist(finalObject entity){ towQoqv
getHibernateTemplate().save(entity); f5'+F-`N
} W{k}ogI;
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publicvoid update(finalObject entity){ 6CCM7
getHibernateTemplate().update(entity); I+}h+[W
} k&9
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publicvoid delete(finalObject entity){ }APf^Ry
getHibernateTemplate().delete(entity); =s;7T!7!
} $[IuEdc/
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publicObject load(finalClass entity, A H`6)v<f
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finalSerializable id){ ).k=[@@V
return getHibernateTemplate().load p`Ax)L\f
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(entity, id); 2 &R-zG
} ;hRo}
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publicObject get(finalClass entity, (d@lG*K
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finalSerializable id){ ujHqwRh
return getHibernateTemplate().get ZU/6#pb
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(entity, id); g&v2=&aj
} Zpg$:Rr
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publicList findAll(finalClass entity){ Dk/;`sXV
return getHibernateTemplate().find("from 9^ )=N=wV
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" + entity.getName()); `NrxoU=
} {]`O $S
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publicList findByNamedQuery(finalString e3&R3{
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namedQuery){ Qb/qUUQO;0
return getHibernateTemplate YMC*<wXN
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().findByNamedQuery(namedQuery); 4h?[NOA"
} 9=Y-w s
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publicList findByNamedQuery(finalString query, .#P'NF(5#
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finalObject parameter){ S$ dFz
return getHibernateTemplate Q!MS_
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().findByNamedQuery(query, parameter); 2B5Z0<
} M~=9ym
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publicList findByNamedQuery(finalString query, [.dF)I3
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finalObject[] parameters){ ux'!1mN
return getHibernateTemplate <t&0[l
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().findByNamedQuery(query, parameters); eA4@)6W P(
} an=8['X
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publicList find(finalString query){ b v~"_)C
return getHibernateTemplate().find WL+I)n8~
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jd#
(query); SVo:%mX
} U)o(}:5xF
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publicList find(finalString query, finalObject LDx1@a|83
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parameter){ &V:iy
return getHibernateTemplate().find gYw4YP0Gz
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(query, parameter); ilHZx2k
} iO~3rWQ
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public PaginationSupport findPageByCriteria ??Q'| r
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(final DetachedCriteria detachedCriteria){ ~sx?aiO
return findPageByCriteria 3[amCKel
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Nyip]VwMJ
} uPQ:}zL2
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public PaginationSupport findPageByCriteria '1_CMr
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(final DetachedCriteria detachedCriteria, finalint &;DK^ta*P
<!EdND =
startIndex){ Z.ky=vCt
return findPageByCriteria TFjb1a,)
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(detachedCriteria, PaginationSupport.PAGESIZE, [< Bk% B5
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startIndex); <k+dJ=f
} KLrxlD4\
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public PaginationSupport findPageByCriteria
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(final DetachedCriteria detachedCriteria, finalint UJ* D
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pageSize, ZxFRE#y~2
finalint startIndex){ a<*q+a(*W
return(PaginationSupport) '@i0~
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getHibernateTemplate().execute(new HibernateCallback(){ Zn0e#n
publicObject doInHibernate F !g>fIg
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(Session session)throws HibernateException { 7&;M"?m&
Criteria criteria = Wa7-N4
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detachedCriteria.getExecutableCriteria(session); )7j jfD\
int totalCount = #q#C_"
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((Integer) criteria.setProjection(Projections.rowCount &c>%E%!"
p8,Rr{
()).uniqueResult()).intValue(); w+($=n~
criteria.setProjection 0N>NX?r
0h=NbLr|S-
(null); 0}H7Xdkp
List items = c&me=WD
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criteria.setFirstResult(startIndex).setMaxResults *oZ]k`-!8
.^
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(pageSize).list(); &8$Gyu
PaginationSupport ps = A{X:p3$eN
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new PaginationSupport(items, totalCount, pageSize, 0P i+ (X
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startIndex); Sy()r 6n
return ps; v,]-;V~<
} i[L5,%5<H
}, true); )S"!)\4 b
} GWd71ZtFO
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public List findAllByCriteria(final ^m
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DetachedCriteria detachedCriteria){ uIh68UM
return(List) getHibernateTemplate o_ng{SL
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().execute(new HibernateCallback(){ -@bOFClE
publicObject doInHibernate -4wr)zjfW
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(Session session)throws HibernateException { Pa)'xfQ$Y6
Criteria criteria = M18> %zM
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detachedCriteria.getExecutableCriteria(session); x
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return criteria.list(); gi {rqM
} k4T`{s}e
}, true); *'&]DJj
} 0MpZdJ
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public int getCountByCriteria(final {0L.,T~g+[
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DetachedCriteria detachedCriteria){ )O+V ft
Integer count = (Integer) >ElK8
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getHibernateTemplate().execute(new HibernateCallback(){ 'k'"+
publicObject doInHibernate t?Ku6Z'
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(Session session)throws HibernateException { /tdRUX
Criteria criteria = (}B3df
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detachedCriteria.getExecutableCriteria(session); okm
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return O}s Mqh
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criteria.setProjection(Projections.rowCount Hnft1
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()).uniqueResult(); 6+UTEw;
} ^=Dz)95c
}, true); LO;7NK
return count.intValue(); m+|yk.md
} k%D|17I
} gUr#3#
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用户在web层构造查询条件detachedCriteria,和可选的
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ;{lb_du2:
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PaginationSupport的实例ps。 k'8tqIUN]
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ps.getItems()得到已分页好的结果集 @#r6->%W
ps.getIndexes()得到分页索引的数组 J5!-<oJ/
ps.getTotalCount()得到总结果数 y
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ps.getStartIndex()当前分页索引 #_SsSD=.Sy
ps.getNextIndex()下一页索引 -xXdT$Xd
ps.getPreviousIndex()上一页索引 G)IK5zCDd
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 nV:RL|p2jw
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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 w2H^q3*
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一下代码重构了。 H-,p.$3}
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我把原本我的做法也提供出来供大家讨论吧: ~2;\)/E\
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首先,为了实现分页查询,我封装了一个Page类: 8kLHQ0pmu
java代码: QXu[<V
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/*Created on 2005-4-14*/ 0Ke2%+yqJ
package org.flyware.util.page; ~KQiNkA\|l
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/** u!-v1O^[
* @author Joa
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* 3a?|}zr4
*/
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publicclass Page { []jbzVwS2
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/** imply if the page has previous page */ qizQt]l
privateboolean hasPrePage; Mt4*`CxtH;
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/** imply if the page has next page */ .?`8B9w
privateboolean hasNextPage; m[CyvcF*u
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/** the number of every page */ d#HlO}
privateint everyPage; x1h&`QUP
R`J.vMT
/** the total page number */ |It&1fz}
privateint totalPage; ,8.$!Zia
>,ABE2t5
/** the number of current page */ [<|$If99\
privateint currentPage; q/^?rd
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/** the begin index of the records by the current M._;3_)%/
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query */ u9m ~1\R*
privateint beginIndex; iR"6VO
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@\r2%M-
/** The default constructor */ F`La_]f?b\
public Page(){ Z,tHyyF?j
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} o%!s/Z1
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/** construct the page by everyPage D\Y,2!I
* @param everyPage n[B[hAT
* */ gFd*\Dk
public Page(int everyPage){ |c>.xt~
this.everyPage = everyPage; c^r WS&)P
} Zoy)2E{
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*
/** The whole constructor */ 5 B t~tt
public Page(boolean hasPrePage, boolean hasNextPage, $<9u:.9xf
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)PkW,214#
int everyPage, int totalPage, @?jtB
int currentPage, int beginIndex){ ~0h@p4
this.hasPrePage = hasPrePage; &=f?:UZ%
this.hasNextPage = hasNextPage; _K&Hiz/'
this.everyPage = everyPage; XG!6[o;
this.totalPage = totalPage; ]j!pK4
this.currentPage = currentPage; +v~x_E5FP
this.beginIndex = beginIndex; \H9:%Tlp~4
} ]9PG"<^k
mE=Ur
/** ?6]B6
* @return ~%2yDhdQ
* Returns the beginIndex. +MD84YR
*/ p6aR/gFkqv
publicint getBeginIndex(){ sH>`eqY
return beginIndex; puLgc$?
} Fv*QcB9K
_%er,Ed
/** S dN&%(ZE
* @param beginIndex EDuH+/:n
* The beginIndex to set. @q`T#vd
*/ 5dhy80|g]
publicvoid setBeginIndex(int beginIndex){ oaZdvu@y
this.beginIndex = beginIndex; C_'EO<w$
} _Hd|y
|Y8}*C\M.h
/** 1szObhN-l
* @return Z\]{{;%4b7
* Returns the currentPage. )&O6d .
*/ Mna
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publicint getCurrentPage(){ c%WO#}r|
return currentPage; xXc>YTK'
} cly} [<w!
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/** ZyDNtX%
* @param currentPage }n
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* The currentPage to set. )t@9!V
*/ alB'l
publicvoid setCurrentPage(int currentPage){ 4U_+NC>b
this.currentPage = currentPage; 73]8NVm
} F,A+O+
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/** )[J@s=
* @return )iM(
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* Returns the everyPage. }6BXa
*/ IuT)?S7O*k
publicint getEveryPage(){ ;c>"gW8
return everyPage; .k-6LR
} 5eE\
X /
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r{
/** 8sU5MQ5
* @param everyPage tjwnFqI
* The everyPage to set. D(;+my2
*/ C
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publicvoid setEveryPage(int everyPage){ 2Wu`Dp;&l
this.everyPage = everyPage; [\#ANA"
} G0|}s&$yL
$,J0) ~
/** 4H(8BNgzV
* @return 2m]4
* Returns the hasNextPage. ErJ/h?+
*/ ^N[ Cip}8
publicboolean getHasNextPage(){ LT
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return hasNextPage; hRRxOr#*$
} H la?\
u
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/** LSA6*Q51
* @param hasNextPage p^*a>d:d]
* The hasNextPage to set. H8I)D& cw
*/ AT+l%%
publicvoid setHasNextPage(boolean hasNextPage){ "?F[]8F.b
this.hasNextPage = hasNextPage; V8):!
} 2J{vfF
x s\<!
/** s+v9H10R
* @return /&Cq-W
* Returns the hasPrePage. Sh1$AGm
*/ $ZGup"z)
publicboolean getHasPrePage(){ `kxC#
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return hasPrePage; l?2
} i+qg*o$
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/** bL`\l!qQx;
* @param hasPrePage >\^oCbqF}~
* The hasPrePage to set. Pj]^p{>
*/ (3mL!1\
publicvoid setHasPrePage(boolean hasPrePage){ p<(a);<L
this.hasPrePage = hasPrePage; v@ OELJX
} 7Y[ q)lv
C4$P#DZT^
/** B*mZxY1
* @return Returns the totalPage. Ahl&2f\
* OblHN*
*/ ;l_b.z0^6
publicint getTotalPage(){ 6WQN!H8+^
return totalPage; z[1uub,)1
} :d9GkC
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/** JZ`SV}\`
* @param totalPage f.uuXK
* The totalPage to set. wkGr}
*/ Iy49o!
publicvoid setTotalPage(int totalPage){ %6 Av1cv
this.totalPage = totalPage; s|H7;.3gp
} Pe,k y>ow
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} 'g,_ lF
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& ;.rPU
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 U`=r.>
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个PageUtil,负责对Page对象进行构造: 5hy7}*dR
java代码: NZv 8#
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/*Created on 2005-4-14*/ *X$qgSW
package org.flyware.util.page; >QvqH 2
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import org.apache.commons.logging.Log; hWbu
Z%
import org.apache.commons.logging.LogFactory; Yg '(
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/** 0.wF2!V.
* @author Joa D((/fT)eD
* )s^gT]"N
*/ nVWU\$Ft
publicclass PageUtil { eA2*}"W
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privatestaticfinal Log logger = LogFactory.getLog 0@b<?Ms9
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(PageUtil.class); XrTc5V
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/** ]}].Aq
* Use the origin page to create a new page @xBb|/I
* @param page #&IrCq+
* @param totalRecords NAE|iyw
* @return XchD3p+uB
*/ D*~Q;q>
publicstatic Page createPage(Page page, int fJ.=,9:<
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totalRecords){ Z{B [r;
return createPage(page.getEveryPage(), yC5>k;/6#K
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!dl
page.getCurrentPage(), totalRecords); ef{Hj[8
} *vRHF1)L
.Qn#wub
/** M5+R8ttc
* the basic page utils not including exception =/|GWQj
=Xr{ Dg
handler T+P{,,a/]
* @param everyPage 4`#%<G
* @param currentPage eyDI>7W
* @param totalRecords hr.mzQd
* @return page .aa7*e
*/ DL~!
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publicstatic Page createPage(int everyPage, int [= E=H*j
vFJ4`Gjw(
currentPage, int totalRecords){ HI D6h!
everyPage = getEveryPage(everyPage); 8q9^
currentPage = getCurrentPage(currentPage); w/o8R3F
int beginIndex = getBeginIndex(everyPage, 1@~%LV
8i`T?KB
currentPage); :%mlsNw
int totalPage = getTotalPage(everyPage, 7YTO{E6]d\
D&mPYxXL
totalRecords); F czia0@z
boolean hasNextPage = hasNextPage(currentPage, %1;Y`>
8cY5:plK
totalPage); K[noW
boolean hasPrePage = hasPrePage(currentPage); K6B6@
j^ 8Hjg
returnnew Page(hasPrePage, hasNextPage, 7SkW!5
everyPage, totalPage, ,:}VbQ:3I
currentPage, md{1Jn"
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beginIndex); }W " i{s/
} u];\v%b
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privatestaticint getEveryPage(int everyPage){ X
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return everyPage == 0 ? 10 : everyPage; `ZC -lAY
} FN sSJU3ld
U/U_q-z]
privatestaticint getCurrentPage(int currentPage){ olo9YrHn
return currentPage == 0 ? 1 : currentPage; /8_x]Es/
} p|;#frj
E?K(MT&@
privatestaticint getBeginIndex(int everyPage, int tx1TtWo
iuEe#B;!
currentPage){ PB8U+
return(currentPage - 1) * everyPage; E(S$Q^
} :Oj!J&A
Us&~d"n
privatestaticint getTotalPage(int everyPage, int :5^5l
H9VdoxKo
totalRecords){ ?5d[BV
int totalPage = 0; A#~CZQY^$
PL\4\dXB
if(totalRecords % everyPage == 0) * e,8o2C$
totalPage = totalRecords / everyPage; M#],#o*G
else 9J49s1
totalPage = totalRecords / everyPage + 1 ; u`+kH8#
fEK%)Z:0
return totalPage; =1B;<aZH!
} v%c--cO(S4
]a~gnz&1
privatestaticboolean hasPrePage(int currentPage){ >]\oVG
return currentPage == 1 ? false : true; QE;,mC>
} Fok`-U
LwQYO'X
privatestaticboolean hasNextPage(int currentPage, `$;%%/tx
MGKSaP;x
int totalPage){ g( eA?
return currentPage == totalPage || totalPage == w~9Y=|YI7
[9CBTSr
0 ? false : true; J0@#xw=+
} ,tFLx#e#
GV)DLHiyxX
N':d
T
} c&L|e$C]
>?X(,c
F JxH{N6a
.ddf'$6h
z{>
)'A/
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 <e8Ux#x/
=p!Hl#
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
5&U?\YNLa
$>l65)(E\
做法如下: <M3&\
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 MIAC'_<-e
NzID[8`
的信息,和一个结果集List: );z/
@Q
java代码: 9@p+g`o
g7LS
7tT L,Nxe
/*Created on 2005-6-13*/ wAF#N1-k
package com.adt.bo; r$d'[ZcX
6CWm;%B#G
import java.util.List; {1wjIo"ptg
Fmrl*tr
import org.flyware.util.page.Page; :?gk=JH:
Q;p%
VQ
/** CM%;r5
* @author Joa +u7nx
*/ za4:Jdr
publicclass Result { 6$$ku
24_/JDz
private Page page; >R6>*|~S
?)c9!hR
private List content; /kd6Yq(y
ud,_^Ul
/**
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* The default constructor ->YF</I
*/ a: OuDjFp
public Result(){ h IUO=f
super(); [E%Ov0OC
} z 4`H<Pn
e#uF?v]O
/** cf1GA
* The constructor using fields jJY!;f
* a
s?)6
* @param page yy3-Xu4
* @param content >9]i#So^
*/ 4ze4{a^
public Result(Page page, List content){ L {i|OK^e
this.page = page; !Ry4w|w
this.content = content; :E9 @9>3S
} k<NEauQ
Z0%Qy+%
/** 7(= 09z
* @return Returns the content. K~>ESMZ5
*/ XF N4m #
publicList getContent(){ V\o&{7!
return content; 0j|JyS:}G
} +~\c1|f
IOOAaa @(
/** A 4|a{\|$
* @return Returns the page. HOAgRhzE
*/ y]ZujfW7
public Page getPage(){ .EoLJHL
}
return page; 8klu*
} )y}W=Q>T
4~/3MG
/** T]Eg9Y:+v
* @param content b6UD!tXp
* The content to set. jPNm $Y1
*/ :s OsG&y
public void setContent(List content){ iPPW_Q9x
this.content = content; 2f$6}m'Ad
} RBzBR)@5
U:
Q&sq8U
/** VlQaT7Q
* @param page n~NOqvT <
* The page to set. U#!f^@&AB
*/ !G3d5d2)C
publicvoid setPage(Page page){ 07L1 "
this.page = page; /"<o""<]
} 7Z<ba^r}
} 6> Szxkz
>A;9Ee"&
/?j
vv&
Lk|%2XGO&
nE3'm[)
2. 编写业务逻辑接口,并实现它(UserManager, S20L@e"U
@eGJ_ J
UserManagerImpl) 2U;ImC1g
java代码: S @'fmjA'
&qP&=( $
u;qBW
uO
/*Created on 2005-7-15*/ xui.63/
package com.adt.service; 0
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+MfdZD
import net.sf.hibernate.HibernateException; Sc zYL?w^
GwoN=
import org.flyware.util.page.Page; le-Q&*
AG$S;)Yl9c
import com.adt.bo.Result; ]dKLzW:l
'4nR ^,
/** eD4o8[s
* @author Joa *h>KeIB;
*/ ]D;X"2I2'b
publicinterface UserManager { ED={OZD8
C&vUZa[p
public Result listUser(Page page)throws Q,mmHw.`J
q^_PR|
HibernateException; v}$KlT
p=65L
}
!Z'x h +
|h; _r&
u!As?AD.
D^knN-nZ*
g=
ql 3N
java代码: ./009p
{\Eqo4A5}
HNRZ59Yyq
/*Created on 2005-7-15*/ X;I;CZ={
package com.adt.service.impl; sacaL4[_<
OXs-gC{b
import java.util.List; 2,Og(_0>
f@%H"8w!
import net.sf.hibernate.HibernateException; L/,W
C]tHk)<|42
import org.flyware.util.page.Page; p<2A4="&
import org.flyware.util.page.PageUtil; t@TBx=16
'@ym-\,
import com.adt.bo.Result; w7?&eF(w(
import com.adt.dao.UserDAO; R)3P"sGuN
import com.adt.exception.ObjectNotFoundException; ^nYS@
import com.adt.service.UserManager; ",c(cYVW
cboue
LEt
/** H\\0V.}!
* @author Joa $vC!Us{z
*/ 8T:|~%Sw
publicclass UserManagerImpl implements UserManager { n\#RI9#\
\/J7U|@Lt
private UserDAO userDAO; yE(> R(^
a+TlZE>8
/** pFLR!/J
* @param userDAO The userDAO to set. 9~^%v zM
*/ n y7G
publicvoid setUserDAO(UserDAO userDAO){ $W46!U3
this.userDAO = userDAO; J2BW>T!tuw
} MjAF&bD^
0pWF\<IZ
/* (non-Javadoc) lH6zZ8rh
* @see com.adt.service.UserManager#listUser @tY)s
))"
*[
(org.flyware.util.page.Page) /Ot=GhN]
*/ u.t(78N
public Result listUser(Page page)throws OKU9v{
dcMWCK
HibernateException, ObjectNotFoundException { #HD$=ECcw
int totalRecords = userDAO.getUserCount(); x: `]uOp
if(totalRecords == 0) =rV*iLy
throw new ObjectNotFoundException e5bRi0
-vcHSwGb
("userNotExist"); (%huWW
j
page = PageUtil.createPage(page, totalRecords); D6trqB
List users = userDAO.getUserByPage(page); {%(_Z`vI
returnnew Result(page, users); ]wg+zOJu]+
} E>tlY&0[$
e~C^*w L
} 9Z,vpTE
!\Y85o>JU
w`(EW>i
FnN@W^/z
85rXm*Df
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 qNP&f8fH
&D
"$N"
询,接下来编写UserDAO的代码: @'.(62v
3. UserDAO 和 UserDAOImpl: M^\#(0^2@
java代码: Vd2bG4*=
fZ2>%IxG}
P;D)5yP092
/*Created on 2005-7-15*/ X'4g\)*
package com.adt.dao; / c1=`OJ
Fi+v:L|
import java.util.List; bq/*99``
=@U~sl[
import org.flyware.util.page.Page; b{|Ha3;w
Yyq:5V!
import net.sf.hibernate.HibernateException; S3V3<4CB
w /$4
Rv+S
/** p/|]])2
* @author Joa ozZW7dveU
*/ $=7[.z&
publicinterface UserDAO extends BaseDAO { 'u }|~u?m
;iJ*.wVq
publicList getUserByName(String name)throws ]de'v
#<V/lPz+
HibernateException; c <8s\2
xEN""*Q
publicint getUserCount()throws HibernateException; &ah!g!o3
;/$=!9^sZ
publicList getUserByPage(Page page)throws UD|Qa
q-%;~LF
HibernateException; HS"E3s8
d'~
k f#
} 0z@KkU{Z
a%"mgCB
'!*,JG5_
.lVC>UT
jM8e2z3
java代码: -lr)z=})
.CI {g2
q@K;u[zFK
/*Created on 2005-7-15*/ rPoPs@CBD
package com.adt.dao.impl; vdFy}#X
?;pw*s1Atz
import java.util.List; Q}GsCmt=)O
9ALE6
import org.flyware.util.page.Page; $2Y'[Dto\
GAONgz|ZI
import net.sf.hibernate.HibernateException; FA-""]
import net.sf.hibernate.Query; ZUJ!
t]|WRQvy8
import com.adt.dao.UserDAO; |~b.rKQt[
t#tAvwFM8
/** USLG G}R
* @author Joa okfGd=
&
*/ }J27Y;Zp9
public class UserDAOImpl extends BaseDAOHibernateImpl {-*+G]
(Zi(6 T\z
implements UserDAO { SoZ$1$o2
Mg?^ 5`*
/* (non-Javadoc) cn&\q.!fh
* @see com.adt.dao.UserDAO#getUserByName ]~g6#@l
J%d\ 7
(java.lang.String) BdcTKC
*/ QeP8Vl&e:
publicList getUserByName(String name)throws ZS0=xS5q)
L&$ X\\Lv^
HibernateException { $\kqh$")
String querySentence = "FROM user in class 4fPbwiKj
= h,6/cs
com.adt.po.User WHERE user.name=:name"; [03$*BCq 3
Query query = getSession().createQuery ". jY3<bQg
r`5[6)+P
(querySentence); +L_!$"I
query.setParameter("name", name); <11pk
return query.list(); UxI0Of&:
} [MfKBlA
DC4,*a~
/* (non-Javadoc) ?4%'6R
* @see com.adt.dao.UserDAO#getUserCount() t_HS0rxG
*/ @vWf-\
publicint getUserCount()throws HibernateException { nQ4 s
int count = 0; @!z9.o;
String querySentence = "SELECT count(*) FROM VT1Nd
M`!\$D
user in class com.adt.po.User"; x&qC~F*QR%
Query query = getSession().createQuery Jolr"F?
E)liuu!qI
(querySentence); ^:g8mt
count = ((Integer)query.iterate().next tFLdBv!=:^
|_V i8Ly
()).intValue(); zlC|Sp af
return count; AfmGA9
} pC 5J
'@
}HB)%C50.
/* (non-Javadoc) C%8nr8po
* @see com.adt.dao.UserDAO#getUserByPage >5C|i-HX
$
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(org.flyware.util.page.Page) U 2k^X=yl
*/ ~A<1xszC
publicList getUserByPage(Page page)throws b|F_]i T
\DsP'-t
HibernateException { sM)qzO2wh
String querySentence = "FROM user in class :#8#tLv
~~eR,HYk
com.adt.po.User"; Sc
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Query query = getSession().createQuery /Po't(-x
icW?a9 b&
(querySentence); kfER
query.setFirstResult(page.getBeginIndex()) ld58R
.setMaxResults(page.getEveryPage()); f,GF3vu"
return query.list(); jUjgxP*7m
} t}LV[bj1u
2\h]*x%:
} ~nk{\ rWO
S;DqM;Q
)-$Od2u2c
9-)D"ZhLe
[4uTp[U!r
至此,一个完整的分页程序完成。前台的只需要调用 <4,hrx&.
,4$ZB(\
userManager.listUser(page)即可得到一个Page对象和结果集对象
9?c0cwP?
r )8[LN-
的综合体,而传入的参数page对象则可以由前台传入,如果用 `I+G7KK
3=w$1.B d
webwork,甚至可以直接在配置文件中指定。 vZj:\geV
'PW~4f/m
下面给出一个webwork调用示例: JSXudz5c
java代码: g{K*EL<
ceN*wkGyB
emp*j@9
/*Created on 2005-6-17*/ a4HUP*
package com.adt.action.user; H^ _[IkuA%
4QbD DvRQ^
import java.util.List; ^Glmg}>q
?f!w:zp
import org.apache.commons.logging.Log; 4B>N[#-0=
import org.apache.commons.logging.LogFactory; Pg[XIfBva
import org.flyware.util.page.Page; ZdbZ^DUR<(
^`ah\L
import com.adt.bo.Result; : vN'eL|#
import com.adt.service.UserService; o*OYZ/_L
import com.opensymphony.xwork.Action; XOsPKq
A[QUFk(
/** 6Yw;@w\
* @author Joa 2QwdDKMS_
*/ FncK#hZ.
publicclass ListUser implementsAction{ *?'nA{a)E
A&%vog]O
privatestaticfinal Log logger = LogFactory.getLog dh r)ra]
<GoUth.#
(ListUser.class); 5Vo8z8]t`
EA.4m3
private UserService userService; 1}1.5[4d
:o$k(X7a
private Page page; ,B|~V 3)(
7x8/Vz@\
privateList users; oujg(
^E
Cf@~W)K
/* Le#>uWM
* (non-Javadoc) ,CiN@T \&
* 0XV8B
* @see com.opensymphony.xwork.Action#execute() ?wzE+p-
*/ ~,[<R
publicString execute()throwsException{ ``*iK
Result result = userService.listUser(page); S<do.{|p[
page = result.getPage(); 1<y(8C6
users = result.getContent(); y[M<x5
return SUCCESS; 13
`Or(>U
} AlP}H~|M7
;.$AhjqiP
/** ;hP43Bi
* @return Returns the page. zu8
*/ wc?`QX}I
public Page getPage(){ b1An2e[
return page; 'qR)f\em
} c*o05pMS
1?:/8l%V
/** (+SfDL$m
* @return Returns the users. +T]/4"^M
*/ M7U:UV)
publicList getUsers(){ [n%=2*1p
return users; J~.8.]gXW
} DIrQ5C
3 !W
M'i
/** CK4C:`YG
* @param page F@ Sw
* The page to set. FbH
1yz
*/ VK>ZH^-
publicvoid setPage(Page page){ QD6<sw@]P
this.page = page; ~z;G$jd
} Zb> UY8
'ii5pxeNI
/** S\$=b_.
* @param users x-0O3IIE
* The users to set. tzH~[n,
*/ pC=kv ve
publicvoid setUsers(List users){ WC2sRv4]3
this.users = users; 3zC<k2B
} ~kHWh8\b:
0?@;zTE0
/** bH6i1c8
* @param userService 4KSZ;fV6/
* The userService to set. ;UU`kk
*/ jtS-nQ|
publicvoid setUserService(UserService userService){ F3)w('h9c
this.userService = userService; >;wh0dBe
} o:oQF[TcFO
} L!/Zw~
K+HP2|#6
)DR/Xu;b
<L!9as]w
d@d\9*mn
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, T#M_2qJ1=
Mk-zeq<2z
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
xWC*DKV
`MD%VHQ9U
么只需要: +!"GYPUXy
java代码: 0oT~6BGm
a!?JVhD&
0Y|"Bo9k
<?xml version="1.0"?> tfz"9PV80
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork mz-sazgV
f2*e&+LjTP
1.0//EN" "http://www.opensymphony.com/xwork/xwork- WdtZ{H
$"e$#<g
1.0.dtd"> 5t=7-
H\r-
;,&
<xwork> @$G{t^&os
Ms>CO7Nvy
<package name="user" extends="webwork- 3UR'*5|'
-] @cUx
interceptors"> q8m[ S4Q]g
]Lb Fh5;s
<!-- The default interceptor stack name zG^|W8um_
~<.%sVwE
--> }0okyGg>q
<default-interceptor-ref lf`" (:./
obzdH:S
name="myDefaultWebStack"/> 7)-uYi]
dA
IjaFNZZC!
<action name="listUser" |BA&ixHe~C
>f\$~cp
class="com.adt.action.user.ListUser"> 3*8m!gq7s
<param xj<
K6
d?6\
name="page.everyPage">10</param> ?1afW)`a.v
<result &x"hM
6<t<hP_3O
name="success">/user/user_list.jsp</result> xI>HY9i)
</action> Z [Q jl*
dy"7Wl]hi7
</package> DeK&_)g| Z
OCN:{
</xwork> r]3v.GZy
MkK6.qV\z
r-e-2y7
K^m`3N"
M&SY2\\TB
{3@"}Eh
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 KFhnv`a.0
j=kz^o~mH
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。 ZCAg)/
APUpqY
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 &iTTal.6
MhDPf]`
Gg
hd>_K*oH
|-Q="7b%
k*ZYT6Z?
我写的一个用于分页的类,用了泛型了,hoho wl Nl|+ K
b O9PpOk+z
java代码: O*lMIWx
HO}eu
v"x'rx#
package com.intokr.util; Bk;/>gD
H tx)MEZ
import java.util.List; p)c"xaTP#F
Ha/Gn!l
/** %) /Bl.{}<
* 用于分页的类<br> 70F(`;
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ?
4v"y@v
* k =
* @version 0.01 mV;)V8'
* @author cheng GhC%32F
*/ ;s^F:O
public class Paginator<E> { ^!7|B3`
privateint count = 0; // 总记录数 vSv:!5*
privateint p = 1; // 页编号 f>[!Zi*
privateint num = 20; // 每页的记录数 ?WBA:?=$58
privateList<E> results = null; // 结果 zlhU[J}"1|
}>yQ!3/i
/** 92D :!C
* 结果总数 lEC91:Jyt
*/ Ih_=yk
publicint getCount(){ )YPut.
return count; jmr1e).];
} +5N09$f;R
9xRor<
publicvoid setCount(int count){ xX~;
/e&,
this.count = count; Gj- *D7X5
} MT^krv(G
]]6
/** /g\m7m)u
* 本结果所在的页码,从1开始 !{S HlS
* 'fka?lL
* @return Returns the pageNo. 9RQw6rL
*/ w9,w?%F
publicint getP(){ V\/5H~L
return p; @u1mC\G
} J%1 2Ey@6
i{MzQE+_^
/** pIgjo>K
* if(p<=0) p=1 f}:W1&LhI?
* \w=*:Z
* @param p qM9> x:V
*/ ]}9D*V
publicvoid setP(int p){ aMO+y91Y(
if(p <= 0) +`+r\*C5
p = 1; 87OX:6
this.p = p; `y*o-St3
} ZJ'FZ8Sx
Uq=!>C8
/** 8?[#\KgH1
* 每页记录数量 6B&ERdoX
*/ G0Wv=tX|
publicint getNum(){ K&;;{~md.
return num; FQO>%=&4
} HyJ&;4rf
T?EFY}f
/** tS
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* if(num<1) num=1 #RTiWD[o
*/ _Bq [c
publicvoid setNum(int num){ q:3HU<
if(num < 1) ,7^,\ ,-m
num = 1; -3|i5,f
this.num = num; }^Ky)**
} 9RnXp&w
Na>?1F"KHk
/** qAirH1#
* 获得总页数 a{4RG(I_
*/ y R_x:,|g
publicint getPageNum(){ 95^-ptO{1`
return(count - 1) / num + 1; (a@}J.lL
} ;0Mg\~T~'
> m##JzWLr
/** NSDls@m
* 获得本页的开始编号,为 (p-1)*num+1 O_|p{65
*/ PJ'.s
publicint getStart(){ 8BggK6X
return(p - 1) * num + 1; dH+oV`
} )jm u*D5N
9p%8VDF=
/** Pskg68W
* @return Returns the results. H<C+rAIb
*/ nI<Ab_EB
publicList<E> getResults(){ |emZZj
return results; ]?n~?dD{]
} j[&C6l+wH
yUlYf#`H
public void setResults(List<E> results){ {+x;J4
this.results = results; z]0UW\S/
} vw/X
x[1(cj
public String toString(){ BZs?tbf
StringBuilder buff = new StringBuilder \"AzT{l!;
zR6^rq*
(); %#-'|~
buff.append("{"); Q??nw^8Hi
buff.append("count:").append(count); \
0aa0=
buff.append(",p:").append(p); Q\{$&0McF
buff.append(",nump:").append(num); a!*K)x,"<
buff.append(",results:").append i~;Yrc%AEX
<|c[
#f
(results); r^$WX@ t&
buff.append("}"); $ZfoJR]%
return buff.toString(); RMO6k bfP
} %N0cp@Vz
0Lki(
} Y|y X]\,
V;>u()
E@D}Sqt