Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 WNo7`)Kx
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 {baG2Fe1`b
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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 wmB_)`QNP
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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 tTE]j-uT
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分页支持类: A~M .v0
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java代码: 8.ej65r*
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package com.javaeye.common.util; ^d@ME<mb
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import java.util.List; FFq8LM8
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publicclass PaginationSupport { KD^n7+w%
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publicfinalstaticint PAGESIZE = 30; LMHiiOs,
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privateint pageSize = PAGESIZE; DI0Wk^ m
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privateList items; 6lob&+
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privateint totalCount; AwtiV-w
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privateint[] indexes = newint[0];
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privateint startIndex = 0; wJF(&P
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public PaginationSupport(List items, int g#lMT%
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totalCount){ /*e6('9s
setPageSize(PAGESIZE); ~?zu5,vb
setTotalCount(totalCount); Aaug0X
setItems(items); S{jm4LZ
setStartIndex(0); i6P'_
} p735i`8
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public PaginationSupport(List items, int WP5Vev9*+
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totalCount, int startIndex){ X:m m<4
setPageSize(PAGESIZE); oer3DD(
setTotalCount(totalCount); I(uM`g
setItems(items); 4w#:?Y
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setStartIndex(startIndex); 1Vx>\A
} e/b
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public PaginationSupport(List items, int 3$4I
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totalCount, int pageSize, int startIndex){ :"'*1S*
setPageSize(pageSize); O`Y@U?^N
setTotalCount(totalCount); s0m k<>z
setItems(items); /HVxZ2bar
setStartIndex(startIndex); dlH&8
} N{H#j6QW
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publicList getItems(){ t1ers> h
return items; *X
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} 3,0b<vfSv
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publicvoid setItems(List items){ >Z>sR0s7
this.items = items; xbzO'C
} w ufQyT`
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publicint getPageSize(){ Ui'*$W]v
return pageSize; ?OFfU 4
} Y^b}~t
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publicvoid setPageSize(int pageSize){ h{:
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this.pageSize = pageSize; tuJ{IF
} kTA4!654
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publicint getTotalCount(){ ?Xj@Sx
return totalCount; @$1jp4c
} G^:?)WRG
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publicvoid setTotalCount(int totalCount){ 7LsVlT[
if(totalCount > 0){ "dHo6CT,y_
this.totalCount = totalCount; )cU$I)
int count = totalCount / w\a6ga!xt"
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pageSize; tA^CuJR
if(totalCount % pageSize > 0) l[^0Ik-G
count++; Q_`EKz;N{
indexes = newint[count]; :}CcWfbT
for(int i = 0; i < count; i++){ T%aM~dp
indexes = pageSize * [e o=
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i; ;Irn{O
} @M6F?;
}else{ :qj7i(
this.totalCount = 0; p@ U[fv8u
} fo~>y
} '4}8WYKQ
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publicint[] getIndexes(){ y?Pw6;e.
return indexes; W4(GI]`_+
} o|w
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publicvoid setIndexes(int[] indexes){ @U:PXCvh
this.indexes = indexes; |CAMdU
} !Y 9V1oVf"
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publicint getStartIndex(){ Ymf@r?F<
return startIndex; K5F;/KR"
} ^ywDa^;-
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publicvoid setStartIndex(int startIndex){ H.[nr:
if(totalCount <= 0) %<`sDO6Q?
this.startIndex = 0; >J#/IjCW
elseif(startIndex >= totalCount) tAkv'.
this.startIndex = indexes 5> !N)pA
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[indexes.length - 1]; FSkLR h
elseif(startIndex < 0) `3*QKi$
this.startIndex = 0; #e1iYFgS
else{ yq[.
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this.startIndex = indexes lYmxd8
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[startIndex / pageSize]; j /@<=
} tJ
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} Z29LtKr
! F<::fN
publicint getNextIndex(){ 7g:Lj,Z4L
int nextIndex = getStartIndex() + -@@
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pageSize; <d O~;
if(nextIndex >= totalCount) LI<Emez
return getStartIndex(); G8'
else ab`9MJc;
return nextIndex; 5!aI~(3<
} ~[=d{M!$W
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publicint getPreviousIndex(){ G
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int previousIndex = getStartIndex() - v`S ;.iD
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pageSize; ;.^!
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if(previousIndex < 0) (}s& 84!
return0; @$nh6l>i
else z]D/Qr
return previousIndex; {$>.I
} dKhS;!K9p
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} 5F!i%{XQvm
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抽象业务类 {`-AIlH(
java代码: Hp5.F>-
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/** nw#AKtd@x
* Created on 2005-7-12 Nw(hN+_u
*/ Qg0%rbE
package com.javaeye.common.business; (" +clb`
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import java.io.Serializable; 8|Ob7+
import java.util.List; HD3WsIim*
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import org.hibernate.Criteria; ~NLthZ(O
import org.hibernate.HibernateException; ?zfm"o
import org.hibernate.Session; KK{_s=t%<
import org.hibernate.criterion.DetachedCriteria; lM#,i\8Q
import org.hibernate.criterion.Projections; o ZQ@ Yu3
import ym_as8A*Q
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org.springframework.orm.hibernate3.HibernateCallback; X&i;WI
import PjXiYc&
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org.springframework.orm.hibernate3.support.HibernateDaoS 5z\,]
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upport; \<dg
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import com.javaeye.common.util.PaginationSupport; YV} "#
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public abstract class AbstractManager extends !b&+2y2i[W
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HibernateDaoSupport { 5z2("[8L&
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privateboolean cacheQueries = false; IZiS3
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privateString queryCacheRegion; Vbe@S?u-
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publicvoid setCacheQueries(boolean {:3:GdM6
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cacheQueries){ Z>3m-:-e
this.cacheQueries = cacheQueries; l<+PA$+}}
} n-{ d7haOa
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publicvoid setQueryCacheRegion(String mSvSdKKKlI
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queryCacheRegion){ 8@LUL)"
this.queryCacheRegion = 9%53_nx?
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queryCacheRegion; dQ_4aO
} fE_%,DJE(
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publicvoid save(finalObject entity){ 2.=u '
getHibernateTemplate().save(entity); m )rVzL
} !m%'aQHH(
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publicvoid persist(finalObject entity){ lw99{y3<<
getHibernateTemplate().save(entity); E'98JZ5ga
} *j,bI Y&se
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publicvoid update(finalObject entity){ `'>~(8&zE
getHibernateTemplate().update(entity); |"S#uJW
} >Vg [A
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publicvoid delete(finalObject entity){ }q'IY:r
getHibernateTemplate().delete(entity); U OGjil{.
} t\'MB
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publicObject load(finalClass entity,
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finalSerializable id){ &/-MUKN
return getHibernateTemplate().load t;/uRN*.
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(entity, id); mBb3Ta
} nRu %0Op
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publicObject get(finalClass entity, AzSu_
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finalSerializable id){ %NJ0Y(:9(
return getHibernateTemplate().get G-|c%g!ejf
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(entity, id); 4;3Vc%
} GB<.kOGQ[
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publicList findAll(finalClass entity){ S'W,AkT
return getHibernateTemplate().find("from d*VvQU8C
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" + entity.getName()); N)Q.P'`N
} g5"I{ol5T~
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publicList findByNamedQuery(finalString t'0&n3
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namedQuery){ *OdmKVw6G
return getHibernateTemplate J\w4N",
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().findByNamedQuery(namedQuery); 4nP4F+
} Ge=^q.
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publicList findByNamedQuery(finalString query, C.":2F;-e
oU @!R
finalObject parameter){ 2+DK:T[
return getHibernateTemplate +N7<[hE;
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().findByNamedQuery(query, parameter); K*2s-,b *
} u\=
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publicList findByNamedQuery(finalString query, <[-{:dH,5
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finalObject[] parameters){ at{p4Sl
return getHibernateTemplate Ha/Qz'^S;
= Ul"{T<
().findByNamedQuery(query, parameters); S.B?l_d^
} [Gv8Fn/aG
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publicList find(finalString query){ lY(_e#
return getHibernateTemplate().find >o v#\
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(query); i+in?!@G:
} s$qc&
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publicList find(finalString query, finalObject oNw=O>v
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parameter){ A+foc5B
return getHibernateTemplate().find +boL?Ix+
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(query, parameter); cYe2a"
} u-s*k*VHoc
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public PaginationSupport findPageByCriteria zVf79UrK
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(final DetachedCriteria detachedCriteria){ rc<Ix
return findPageByCriteria Zi7cp6~7
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); vu.?@k@
} V*fv>f:Yv
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public PaginationSupport findPageByCriteria 8#tuB8>
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(final DetachedCriteria detachedCriteria, finalint _yR_u+5
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startIndex){ QdcuV\B}
return findPageByCriteria q+oc^FD?@
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(detachedCriteria, PaginationSupport.PAGESIZE, 42tZBz&
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startIndex); ILl~f\xG)
} S ~h*U2
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public PaginationSupport findPageByCriteria ,ayJgAD
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(final DetachedCriteria detachedCriteria, finalint !G[%; d
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pageSize, dI%ho<zm]
finalint startIndex){ ma@V>*u
return(PaginationSupport) #qF1z}L(
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getHibernateTemplate().execute(new HibernateCallback(){ r)Lm| S
publicObject doInHibernate .I_<\h7
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(Session session)throws HibernateException { 4k3pm&
Criteria criteria = $oM>?h_=
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detachedCriteria.getExecutableCriteria(session); g] }!
int totalCount = 0%[IG$u)|
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((Integer) criteria.setProjection(Projections.rowCount p4k}B. f
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()).uniqueResult()).intValue(); ]1>R8
criteria.setProjection TIl 'Z7
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(null); ;L -)$Dy4
List items = #\}FQl6
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criteria.setFirstResult(startIndex).setMaxResults {5{VGAD&]>
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(pageSize).list(); p U !:
PaginationSupport ps = t$Ff$(
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new PaginationSupport(items, totalCount, pageSize, UjoA$A!Od;
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startIndex); (7b9irL&cn
return ps; {'h&[f>zcQ
} v&/H6r#E.
}, true); |?{V-L
} +y'2 h%>h[
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public List findAllByCriteria(final ,"gPd!HD(
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DetachedCriteria detachedCriteria){ Dqc
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return(List) getHibernateTemplate 46e?%0(
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().execute(new HibernateCallback(){ : -#w
publicObject doInHibernate uF}dEDB|;
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(Session session)throws HibernateException { %~M* <pN
Criteria criteria = ;ZAwf0~
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detachedCriteria.getExecutableCriteria(session); o_mjI:
return criteria.list(); <dD!_S6@,
} Lp(`m=;O
}, true); hbvcIGaT
} '1b)(IW
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public int getCountByCriteria(final ;UpJ_y)n8\
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DetachedCriteria detachedCriteria){ WrDFbcH
Integer count = (Integer)
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getHibernateTemplate().execute(new HibernateCallback(){ zz(|V
publicObject doInHibernate p o)lN[v
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(Session session)throws HibernateException { m3pDFI
Criteria criteria = U_PH#e
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detachedCriteria.getExecutableCriteria(session); F09%f"9
return Xy K,
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criteria.setProjection(Projections.rowCount $"|r7n5[
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()).uniqueResult(); 1~~GF_l?
} a$Ud"
}, true); ?K:\WW
return count.intValue(); .$}z</#!
} =d ;#Nu-
} PpG;5
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用户在web层构造查询条件detachedCriteria,和可选的 G]k[A=dg
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 :* ]#n
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PaginationSupport的实例ps。 j;y(to-e>D
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ps.getItems()得到已分页好的结果集 4Ps;Cor+
ps.getIndexes()得到分页索引的数组 zw+wq+2"
ps.getTotalCount()得到总结果数 Hqs-q4G$
ps.getStartIndex()当前分页索引 gAztdAsLM
ps.getNextIndex()下一页索引 P,)D0i
ps.getPreviousIndex()上一页索引 ey[Z<i1
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 )b]wpEFl
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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 g.`Ntsi$wI
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一下代码重构了。 qQDe'f~
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我把原本我的做法也提供出来供大家讨论吧: svEe@Kt`
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首先,为了实现分页查询,我封装了一个Page类: Myg;2 .
java代码: g7hI9(8+
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/*Created on 2005-4-14*/ %SIll
package org.flyware.util.page; ?K2EK'-q
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/** GEVDXx>@
* @author Joa 'do2n/
* Uq'W<.v5
*/ S{e3aqT#N
publicclass Page { 9<3}zwJ
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/** imply if the page has previous page */ C|Gk}
privateboolean hasPrePage; VV$#<D<)
j?o6>j
/** imply if the page has next page */ W>+`e]z
privateboolean hasNextPage; RiR],Sj
x!s=Nola
/** the number of every page */ QbHX.:C
privateint everyPage; 9QHj$)?k,
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/** the total page number */ |gxPuAXa)
privateint totalPage; tF/Ni*\^rV
;g#nGs>
/** the number of current page */ 7w9'xY
privateint currentPage; tx<^PV2
hVB(*WA^D
/** the begin index of the records by the current ,Il) t H
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query */ @UdF6:T
privateint beginIndex; #Pd__NV"\
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/** The default constructor */ ;J+iwS*Z
public Page(){ [6g$;SicT
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} Dl0{pGK~
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/** construct the page by everyPage fNx!'{o"
* @param everyPage ~V ?z!3r-)
* */ ]CcRI|g}
public Page(int everyPage){ _\k?uUo&,^
this.everyPage = everyPage; ;!
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} 1@LUxU#Uu$
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/** The whole constructor */ ^.@%n1I"5y
public Page(boolean hasPrePage, boolean hasNextPage, MRo_An+
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int everyPage, int totalPage, .UX4p
=
int currentPage, int beginIndex){ kUGFg{"
this.hasPrePage = hasPrePage; GL9'dL|
this.hasNextPage = hasNextPage; 7>MG8pf3a
this.everyPage = everyPage; K^"l.V#J
this.totalPage = totalPage; DEkv,e
this.currentPage = currentPage; W58?t6!
=
this.beginIndex = beginIndex; {y5 L
} C]JK'K<7-
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/** FhBV.,bU,m
* @return y?r`[{L(lA
* Returns the beginIndex. M/[_~
*/ ~AaEa,LQ
publicint getBeginIndex(){ ?ZC!E0]
return beginIndex; Ug0c0z!b
} ,{(XT7hr
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/** =6\^F i
* @param beginIndex rZB='(?
* The beginIndex to set. x.pg3mVd>
*/ nLk`W"irM
publicvoid setBeginIndex(int beginIndex){ i E;F=Rb
this.beginIndex = beginIndex; pd,d"+
} /TB{|_HbW
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/** M(\{U"%@?
* @return |XQ_4{
* Returns the currentPage. Pz
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*/ QAo/d4
publicint getCurrentPage(){ u~FVI
return currentPage; Oop6o$k
} wmR~e
^ @=4HtA
/** lqrI*@>Tz
* @param currentPage ,1CmB@
* The currentPage to set. b$nev[`{6
*/ 2-UD^;0
publicvoid setCurrentPage(int currentPage){ $g VbeQ
this.currentPage = currentPage; >;j&]]-&
} W79.Nj2`
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/** :6(@P1vA 6
* @return yXEI%2~)
* Returns the everyPage. UYy #DA
*/ {=J:
publicint getEveryPage(){ }C["'tLX
return everyPage; EAWBgOO8iC
} %}~(%@qB>+
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/** ?A .ah
* @param everyPage %c]N-
* The everyPage to set. !L9]nO 'BL
*/ c}),yQ|!:
publicvoid setEveryPage(int everyPage){ yEh{9S%6p
this.everyPage = everyPage; ndN*X'
} >hG*=4oh
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/** }{,Wha5\n
* @return
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* Returns the hasNextPage. >fT%CGLC0
*/ xbcmvJrG
publicboolean getHasNextPage(){ e_!Z-#\J%
return hasNextPage; hHDLrr
} bJ6C7-w:wa
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/** T?Z^2.Pvc
* @param hasNextPage hG<[F@d
* The hasNextPage to set. p0CPeH
*/ CsT&}-C
publicvoid setHasNextPage(boolean hasNextPage){
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this.hasNextPage = hasNextPage; f2Xn !]o
} sc# EL~
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/** .tHc*Eh
* @return 7cB{Iq0+
* Returns the hasPrePage. `YZl2c<w*
*/ tGXH)=K
publicboolean getHasPrePage(){ \WdSj
return hasPrePage; x\:KfYr4Y;
} br k*;
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/** 1BEc"
* @param hasPrePage c3#eL
* The hasPrePage to set. QKVOc,Fp7i
*/ <u#
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publicvoid setHasPrePage(boolean hasPrePage){ @ %q>Jd
this.hasPrePage = hasPrePage; ve.P{;;Ky
} c\ZnGI\|
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/** d,
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* @return Returns the totalPage. # SJJ@SM
* _"t>72
`
*/ S+t2k&pm
publicint getTotalPage(){ *6=9 8C4I
return totalPage; )xz_}6b]
} rADzJ#CU\
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/** B *6ncj
* @param totalPage LIz'hfS!
* The totalPage to set.
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*/ (w(k*b/
publicvoid setTotalPage(int totalPage){ AkO);4A;Jd
this.totalPage = totalPage; :Zob"*T
} 6<5:m:KE
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} =h
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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 Tj<B;f!u
7D'D7=Z.
个PageUtil,负责对Page对象进行构造: 3a ZS1]/
java代码: mtE+}b@(!&
WMWMb3
vLq%k+D#
/*Created on 2005-4-14*/ SlT>S1`rnG
package org.flyware.util.page; cQBc6eAi
#QSSpsF@
import org.apache.commons.logging.Log; i-@V
import org.apache.commons.logging.LogFactory; R@_3?Z!W=
sD{Wc%5
/** kw2d<I$]
* @author Joa 1_c%p#?K
* GM)q\Hx{
*/ NNE(jJ`/
publicclass PageUtil { u.?jW vcv
3qH1\
privatestaticfinal Log logger = LogFactory.getLog O1DUBRli!q
yxf#@Je"
(PageUtil.class); $bZ-b1{c C
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/** s6_i>
* Use the origin page to create a new page b9-3
* @param page Y}Y~?kE>M|
* @param totalRecords L?&&4%%
* @return L=C#E0{i
*/ :!?Fq/!
publicstatic Page createPage(Page page, int Bx$?*y&f!v
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totalRecords){ TGPZUyi3!=
return createPage(page.getEveryPage(), mV4gw'.;7
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page.getCurrentPage(), totalRecords); E?BF8t_fTE
} hy$VG%b;#
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/** -O-?hsV)y
* the basic page utils not including exception g4 +Hq *
.ns=jp
handler :^>&t^E
* @param everyPage v?Cakwu
* @param currentPage w&J_c8S
* @param totalRecords =]pEvj9o
* @return page ^L7!lzyo
*/ &1`Y&x:p
publicstatic Page createPage(int everyPage, int H/;AlN|!
<$25kb R5K
currentPage, int totalRecords){ e+VE FWz
everyPage = getEveryPage(everyPage); h9iQn<lp4.
currentPage = getCurrentPage(currentPage); 5tZ0zr
int beginIndex = getBeginIndex(everyPage, \$ss
8_S| 8RW(
currentPage); .j**>&7L
int totalPage = getTotalPage(everyPage, elpTak@
/_Ku:?{
totalRecords); }Ujgd2(U
boolean hasNextPage = hasNextPage(currentPage, ('\sUZ+5
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totalPage); k9:|CEP
boolean hasPrePage = hasPrePage(currentPage); ji.?bKqHE
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returnnew Page(hasPrePage, hasNextPage, tXZMr
everyPage, totalPage, )/~o'M3
currentPage, ]fU&?z#
H~>8q~o]
beginIndex); <X1lq9 lW
} }4h0{H
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privatestaticint getEveryPage(int everyPage){ ,\aLv
return everyPage == 0 ? 10 : everyPage; eQn[
} ?cKTeGrS
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privatestaticint getCurrentPage(int currentPage){ WpnP^gmX
return currentPage == 0 ? 1 : currentPage; %f1IV(3Qc
} Hr!$mf)h
-Wh 2hWg+
privatestaticint getBeginIndex(int everyPage, int {9x>@p/
;fN^MW@&[
currentPage){
_Rkvg-
return(currentPage - 1) * everyPage; dn Sb}J
} f\.y z[
cx&\oP
privatestaticint getTotalPage(int everyPage, int n4}e!
twbxi{8e.
totalRecords){ 8ZM#.yBB
int totalPage = 0; GU/-L<g
P4eH:0=#
if(totalRecords % everyPage == 0) FH$q,BI!R
totalPage = totalRecords / everyPage; _G'A]O/BZD
else x#zj0vI-8
totalPage = totalRecords / everyPage + 1 ; Cg`lQYU
7l~^KsX
return totalPage; *,*O.#<6
} ~kSOYvK$'
t*A[v
privatestaticboolean hasPrePage(int currentPage){ UX<-jY#'V
return currentPage == 1 ? false : true; NJ-Ji> w
} J2!
Q09 }5
iXL^[/}&?M
privatestaticboolean hasNextPage(int currentPage, vNl)ltzJF
dga4|7-MY
int totalPage){ BGwD{6`U
return currentPage == totalPage || totalPage == l"DHG`kb
,R3TFVV!?
0 ? false : true; m.! M#x2!
} Di4GaKa/
>w,jaQ
M+HhTW;I=
} =l${p*ABQ
yG7H>LF?8
^~7Mv^A
3/yt
dC-~=}HR^
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 KRcB_(
sK&kp=zu
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 @F$}/
{2D|,yH=
做法如下: X# ud5h
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 v>Kh5H5e~
g;6/P2w
的信息,和一个结果集List: B, H9EX
java代码: D_ ~;!^
]vn*eqd
SE6(3f$
/*Created on 2005-6-13*/ 1TR+p? "
package com.adt.bo; |B*B>P#
BmccSC;o4
import java.util.List; :
xggo
DLqH*U
import org.flyware.util.page.Page; :D-D+x
#W3H;'~/5
/** q1x[hv3
pP
* @author Joa ~9yKMUf
*/ g}gGm[1SUo
publicclass Result { m{X{h4t
S<cz2FlV
private Page page; 0j6b5<Gpc*
L%Rw]=v}v
private List content; eB1NM<V
D M+MBK
/** I9>vm]
* The default constructor &0%Zb~ts
*/ F --b,,
public Result(){ dg|x(p#
super(); SOM? 0.
} T#E$sZ
YGLq~A
/** v~T)g"_|
* The constructor using fields / Wjc\n$'
* <2&qIvHL
* @param page &B[*L+-E
* @param content DrV[1Z
*/ S#B%[3@
public Result(Page page, List content){ S Z/yijf
this.page = page; bPP@
this.content = content; ipp`9 9
} h9<PP2.(
1hgIR^;[b
/** ,pdzi9@=t
* @return Returns the content. &y=OZ
!M
*/ 3%1wQXr0
publicList getContent(){ A46q`l9B
return content; kc P ZIP:
} W)/f5[L
8~R.iqLoX
/** p#]9^oA
* @return Returns the page. f77W{T4
*/ L/-SWid)
public Page getPage(){ ol/@)k^s>
return page; nAl
\9#M
} L
FJ@4]%V
+pYwc0~
/** 0=6mb]VUi=
* @param content 1t &_]q_
* The content to set. g |?}a]G
*/ 5YNAb/!!F
public void setContent(List content){ "N=$=Dy>
this.content = content; ]wEI*c(
} C=q&S6/+
h'=)dFw7
/** { >izfG,\
* @param page \i//Aq
* The page to set. Ib{l$#
*/ ?&eS }skL
publicvoid setPage(Page page){ 0[%{YmI{W
this.page = page; V61oK
} f~a
7E;y
} e.DN,rhqI
#I0FWZ>W
3?"gfw W
iBbaHU*V
:'C?uk ?
2. 编写业务逻辑接口,并实现它(UserManager, L%5y@b{AR
U!o
UserManagerImpl)
f&^}yqmuE
java代码: 3MHpP5C
p19(>|$J
.$x}~Sw
/*Created on 2005-7-15*/ 9v*y&V9/
package com.adt.service; JluA?B7E
>W-xDzJry
import net.sf.hibernate.HibernateException; 3I( n];
EHn!ZrQgh
import org.flyware.util.page.Page; :6t73\O
h;+O96V4.
import com.adt.bo.Result; >TCit1yD
G`0{31us
/** rCA!b"C2
* @author Joa UsU
Ri
*/ 9(S=0<
publicinterface UserManager { ';Nc;9
H@wjZ;R
public Result listUser(Page page)throws yy8BkG(
K\xM%O?
HibernateException; XBCHJj]k
r^C(|Vx
} iZdl0;16[
0R\.G1f%
2INpo
,pTZ/#vP#
9ETdO,L)f
java代码: X{Vs
9H4"=!AAgD
i>h3UIx\
/*Created on 2005-7-15*/ O*?^a7Z)4
package com.adt.service.impl; 5ILKYUg,
^i_v\E[QU
import java.util.List; yQj J-g(.
af>i
import net.sf.hibernate.HibernateException; L,#YP#O,j
rqN+0CT
import org.flyware.util.page.Page; c)^A|{,G
import org.flyware.util.page.PageUtil; 5 cQ]vb
jmv=rl>E*
import com.adt.bo.Result; J0R{|]W8
import com.adt.dao.UserDAO; 8w[O%
import com.adt.exception.ObjectNotFoundException; >@bU8}rT
import com.adt.service.UserManager; +<xQF
-YQS\@?
/** ;k#_/c
* @author Joa RbxQTM_:M
*/ e> 9X
publicclass UserManagerImpl implements UserManager { 7lwI]/ZH*
ti9e(Jt!O
private UserDAO userDAO; bIBF2m4
Z.@n7G
/** LXby(|<j
* @param userDAO The userDAO to set. L9Zz-Dr s
*/ =GP L>a&
publicvoid setUserDAO(UserDAO userDAO){ k CGb~+
this.userDAO = userDAO; ATc!c +
} uQ[,^Ee&/
420K6[
/* (non-Javadoc) }15&<s
* @see com.adt.service.UserManager#listUser ~$4(|Fq/
UYZC% $5x
(org.flyware.util.page.Page) UIf#Gy|l
*/ (NR( )2
public Result listUser(Page page)throws `&fW<5-
=d5;F`m
HibernateException, ObjectNotFoundException { >T[Y>]
int totalRecords = userDAO.getUserCount(); `fEzE\\!*
if(totalRecords == 0) [|*7"Q(
throw new ObjectNotFoundException [Fag\/Y+
8(K:2
("userNotExist"); ,R-k]^O
page = PageUtil.createPage(page, totalRecords); xu-bn
List users = userDAO.getUserByPage(page); RE4#a2
returnnew Result(page, users); RF2I_4
} I(BJ1 8F$
wY\,b*x
}
dI7rx+L
lbovwj
$0$sDN6)x
:/][ n9J^
mGDc,C=5:
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Nes|4Z<
4pXY7+e2'
询,接下来编写UserDAO的代码: RZpjr !R
3. UserDAO 和 UserDAOImpl: xE--)=<$
java代码: KV;q}EyG
.0U[nt6
OzC%6;6h
/*Created on 2005-7-15*/ 4NaT@68p
package com.adt.dao; 4j'rbbs/
AdDR<IW
import java.util.List; 5 8;OTDR!
CfrO1i F
import org.flyware.util.page.Page; & }j;SK5
*<
fJgc"3
import net.sf.hibernate.HibernateException; p(GI02|n
'M? ptu?f
/** hUvA;E(qD
* @author Joa ;
Gv-$0{P3
*/ g6DIWMoO=h
publicinterface UserDAO extends BaseDAO { =(TMcu$4`
ckP AH E@
publicList getUserByName(String name)throws @Q ~;@M
yG~Vvpv
HibernateException; X[<#B5
J#@+1 Nt
publicint getUserCount()throws HibernateException; e&ZTRgYdi
a[zVC)N0
publicList getUserByPage(Page page)throws 525^/d6v
N|)e {|k
HibernateException; N&k\X]U
n'pJl
} #H Jlm1d
Z&H_+u3j
}8"i~>>a
17l?li
pg,JYn
java代码: .sj/Lw}
3''Kg<k,I
j8?! J^TC
/*Created on 2005-7-15*/ K9ih(fh)
package com.adt.dao.impl; dQp>z%L)
vzSjfv
import java.util.List; Bmt8yR2
bY,dWNS:
import org.flyware.util.page.Page; UHfE.mTjM
~LFM,@
import net.sf.hibernate.HibernateException; L*6<h
import net.sf.hibernate.Query; ^P [#YO
A`(Cuw-o
import com.adt.dao.UserDAO; 6yYd~|T.Fl
n?q+:P
/** s`,g4ce`
* @author Joa {s6#h #U
*/ rW O#h{
public class UserDAOImpl extends BaseDAOHibernateImpl gV:0&g\v
x=W s)&H_Y
implements UserDAO { <]oPr1
4V]xVma
/* (non-Javadoc) 5?(dI9A"K
* @see com.adt.dao.UserDAO#getUserByName i[.7 8K-s
SZtSUt(ss
(java.lang.String) "=40%j0
*/ 5mudww`
publicList getUserByName(String name)throws _E-{*,7bZS
6b` Jq>v
HibernateException { 9~K>c
String querySentence = "FROM user in class U/v)6:j)4R
%M^Q{`
:5
com.adt.po.User WHERE user.name=:name"; Ym
-U{a
Query query = getSession().createQuery =/ !A
0@u{(m
(querySentence); ~_ovQ4@
query.setParameter("name", name); }p)a7xn}
return query.list(); yVPFH~1@\
} WoSKN7*
hD,^mru
/* (non-Javadoc) hOIg7=v
* @see com.adt.dao.UserDAO#getUserCount() drwxrZt
*/ =''*'a-P
publicint getUserCount()throws HibernateException { Y<@_d
int count = 0; l:#'i`;
String querySentence = "SELECT count(*) FROM slr>6o%W`
0}kvuuR
user in class com.adt.po.User"; 3_eg'EP.E
Query query = getSession().createQuery f
e^s`dsG
= K`]cEL
(querySentence); !#olG}#[
count = ((Integer)query.iterate().next GV9pet89yu
[>j.x2=
()).intValue(); bgInIe
return count; Ia^/^>
} )J[Ady^5
.'-t>(}v
/* (non-Javadoc) [a^<2V!vMn
* @see com.adt.dao.UserDAO#getUserByPage 1&=2"
rX`fjS*C
(org.flyware.util.page.Page) ZiH4s|
*/ bhZ5-wo4%
publicList getUserByPage(Page page)throws |NjyO>@Pa
wlP%
U
HibernateException { e6T?2`5P
String querySentence = "FROM user in class lL'K1%{+
\
^ilgd
com.adt.po.User"; 2v*X^2+
Query query = getSession().createQuery 1o
&(x>J:b
(querySentence); sJg3WN
query.setFirstResult(page.getBeginIndex()) TQ {8 ee{
.setMaxResults(page.getEveryPage()); f,@~@f
X
return query.list(); 4 T/ ~erc
} yN#]Q}4
,
d4i0;2}+
} !E *IktAI
|IWm:[H3
WCI'Kh
%+
MYg^
|ew:}e: k<
至此,一个完整的分页程序完成。前台的只需要调用 % <%r
L{c\7
userManager.listUser(page)即可得到一个Page对象和结果集对象 ~;wR}s<}(
<&t[E0mU
的综合体,而传入的参数page对象则可以由前台传入,如果用 SQw"mO
K~8!Gh{h]
webwork,甚至可以直接在配置文件中指定。 .d4&s7n0
]b^bc2:
下面给出一个webwork调用示例: %NL7XU[~
java代码: P\
2Bx *e
f5nAD
&v r0{]V^
/*Created on 2005-6-17*/ rN {5^+w
package com.adt.action.user; `zcpaE.@
:\1vy5 _
import java.util.List; W5RZsS]
-dUXd<=ue
import org.apache.commons.logging.Log; }-WuHh#
import org.apache.commons.logging.LogFactory; XToYtdt2
import org.flyware.util.page.Page; <,nd]a
7^h*rL9
import com.adt.bo.Result; V}G;oz&>)
import com.adt.service.UserService; IS!]!s'EI
import com.opensymphony.xwork.Action; Lb2/ Te*
*>j4tA{b@v
/** TrHUM4
* @author Joa @ v}M\$N?
*/ T!5g:;~y >
publicclass ListUser implementsAction{ .lppT)P
!AL?bW
privatestaticfinal Log logger = LogFactory.getLog _3_o/I
IBv9xP]BZ
(ListUser.class); nyd'79~>G
LoS%FI
private UserService userService; {Hxziyv~Y(
MCfDR#a
private Page page; M5LqZyY
55x.Q
privateList users; k%cT 38V*
FBI^}^#_
/* a^9}ceu?
* (non-Javadoc) &R}2/Mt
* /vFdhh
* @see com.opensymphony.xwork.Action#execute() `ve5>aw0_Y
*/ 4*+)D8
publicString execute()throwsException{ T(eNK
c2
Result result = userService.listUser(page); }nNCgH
page = result.getPage(); 3ry0.
users = result.getContent(); [UaM}-eR
return SUCCESS; Pexg"328
} )G9,5[
Ob7F39):N
/** WAh{*$Rpl
* @return Returns the page. *s"{JrG`O
*/ "V7 &@3
public Page getPage(){ 0-A@X>6bs
return page; ).> O6A4:C
} ,N5-(W
lV<j?I~?Q
/** |Ns[{/
* @return Returns the users. Qc"UTvq
*/ I78huYAYA
publicList getUsers(){ 0SWec7G
return users; nSV
OS6
} PF/eQZ*4
25`6V>\
/** Ps7Bt(/
* @param page k7Xa|&fQP<
* The page to set. D&#ph%U,P
*/ ^T/d34A;SP
publicvoid setPage(Page page){ w#`E;fN'
this.page = page;
{3=]cLtt
} IH'&W
FFqqAT5
/** \P0>TWE
* @param users M&K'5G)7
* The users to set. PaYsn *{})
*/ 5J8U] :Y)
publicvoid setUsers(List users){ wloQk(T<W
this.users = users; gS4@3BOw&.
} +}0/ %5 =1
D[ (A`!)
/** +&hd3
* @param userService bIahjxd:
* The userService to set. g)#neEA J
*/ q~:k[@`.
publicvoid setUserService(UserService userService){ {kgV3 [%>
this.userService = userService; 2_lb+@[W
} ey>V^Fj
} r5N.Qt8
^<O=<tN\
hbv>Jjd
s@ vHU4
3]1uDgfr
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, F%pYnHr<
8yV?l7
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 ohe0}~)V
Y-Gqx
么只需要: juQQ
java代码: }_L,Xg:I
Fm3B8Int
Ks@
<?xml version="1.0"?> 8n^v,s >
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork w{;esU
nv^nq]4'Dq
1.0//EN" "http://www.opensymphony.com/xwork/xwork- yb:Xjg7
\vvV=iw
1.0.dtd"> <Sx-Ca7
?oX.$E?(
<xwork> J}cqBk>
I+]q;dF;
<package name="user" extends="webwork- EpCsJ08K
..xg4V/
interceptors"> &k4)&LQJ
Ec^x
<!-- The default interceptor stack name hWujio/h
h{&}p-X&[
--> qZ6Mk9@M
<default-interceptor-ref MjW g
Oy^)lF/
name="myDefaultWebStack"/> ,f;YJHEx8
:Ojsj_Z;;
<action name="listUser" ~]_gq;bG
!!4` #Z0+#
class="com.adt.action.user.ListUser"> D> |R.{
<param ' s6SKjZS
7C%z0/
name="page.everyPage">10</param> 4iiW{rh4
<result Z;6v`;[
<