Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 6/6Rah!
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 X>t3|h
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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 bxwkTKr'
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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 c@(1:,R
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分页支持类: CCqT tp
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java代码: =j~Q/-`EC0
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package com.javaeye.common.util; @B`Md3$7
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import java.util.List; .X
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publicclass PaginationSupport { YH\j@^n
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publicfinalstaticint PAGESIZE = 30; ~Ltr.ci
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privateint pageSize = PAGESIZE; N:x0w+Ca
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privateList items; l67KJ
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privateint totalCount; ?`AGF%zp
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privateint[] indexes = newint[0]; vM4<d>
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privateint startIndex = 0; ssl&5AS
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public PaginationSupport(List items, int aB"xqh)a}T
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totalCount){ ut&/\k=N
setPageSize(PAGESIZE); KcXpH]>!9
setTotalCount(totalCount); 6G_<2bO
setItems(items); ue0s&WF|
setStartIndex(0); $}tjS3klr
} Gt~JA0+C)7
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public PaginationSupport(List items, int w sY}JT
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totalCount, int startIndex){ 8eyl,W=dn
setPageSize(PAGESIZE); NL!9U,h5|
setTotalCount(totalCount); B9M>e'H%<
setItems(items); z"379b7cN
setStartIndex(startIndex); p2d\ZgWD=)
} 9lspo~M
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public PaginationSupport(List items, int tu}>:mk
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totalCount, int pageSize, int startIndex){ keCRvl Z4
setPageSize(pageSize); QxpKX_@Q5
setTotalCount(totalCount); ai^|N.!
setItems(items); P}r)wAt
setStartIndex(startIndex); 4~|<`vqN
} ,rO[mNk9@
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publicList getItems(){ I>"Ci(N
return items; +>YfRqz:KB
} L`3n2DEBf
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publicvoid setItems(List items){ :&yDqoQKJ
this.items = items; 'Q|c@t
} 2 ZG@!Y|
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publicint getPageSize(){ OJ,m1{9$}
return pageSize; flnVYQe
} I3) Zr+
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publicvoid setPageSize(int pageSize){ U^_D|$6
this.pageSize = pageSize; I>n
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} nSS=%,?
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publicint getTotalCount(){ u"+}I,'L
return totalCount; 6|=j+rScv
} J^zi2jtV
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publicvoid setTotalCount(int totalCount){ I}.i@d'O
if(totalCount > 0){ `W5-.Tv
this.totalCount = totalCount; aj8Rb&
int count = totalCount / eegx'VSX4
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pageSize; E*CcV;
if(totalCount % pageSize > 0) 9&
count++; 4gZ&^y'
indexes = newint[count]; ~W{-Q.
for(int i = 0; i < count; i++){ _vl}*/=Hc
indexes = pageSize * wCb(>pL0
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i; b?VV'{4
} @;)PSp*j
}else{ aC^$*qN-)
this.totalCount = 0; f8n
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} -5Utlos
} 1>pe&n/
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publicint[] getIndexes(){ 0(\+-<
return indexes; ls|LCQPx
} I.V:q!4*
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publicvoid setIndexes(int[] indexes){ WUoOGbA `
this.indexes = indexes; ,YLF+^w-
} D"l+iVbBP
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publicint getStartIndex(){ ;L"!I3dM)
return startIndex; YT-=;uK^S
} ")UwkF
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publicvoid setStartIndex(int startIndex){ s] au/T6b
if(totalCount <= 0) p]&j;H.
this.startIndex = 0; 1mgLX_U9
elseif(startIndex >= totalCount) Ew,T 5GG
this.startIndex = indexes eSy(~Y
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[indexes.length - 1]; ,.mBJSE3
elseif(startIndex < 0) !@L=;1,
this.startIndex = 0; raUs%Y3
else{ oy\B;aAK
this.startIndex = indexes 7+,vTsCd
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[startIndex / pageSize]; q31>uF
} 3Qn!y\#
} t~p
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publicint getNextIndex(){ m5c&&v6%"b
int nextIndex = getStartIndex() + hv)8K'u
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pageSize; ~)X[(T{
if(nextIndex >= totalCount) TwahR:T
return getStartIndex(); S\ ,mR4:
else *I*i>==Z
return nextIndex; :nJgwp()@
} '\7G@g?UZ
4
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publicint getPreviousIndex(){ ?u$u?j|N
int previousIndex = getStartIndex() - dF@)M
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pageSize; 2HL9E|h
if(previousIndex < 0) /DFV$+9
return0; <PD?f/4 /
else /n5n
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return previousIndex; <z)m%*lvU
} MZ4c{@Tg
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} ]7YNIS
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抽象业务类 kI\tqNJ i
java代码: Snw3`|Y~<
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/** GF<[ }
* Created on 2005-7-12 ?A*Kg;IU
*/ S33j?+Vs
package com.javaeye.common.business; WrGK \Vw[
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import java.io.Serializable; .T B"eUy
import java.util.List; Qs 2.ef?
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import org.hibernate.Criteria; #;VA5<M8
import org.hibernate.HibernateException; #@.-B,]
import org.hibernate.Session; @_ygnNn4R
import org.hibernate.criterion.DetachedCriteria; @4+#Xd7"
import org.hibernate.criterion.Projections; :py\|
import _=f=f cl
c/3$AUsuO
org.springframework.orm.hibernate3.HibernateCallback; (c\hy53dP
import 'xK.UI
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org.springframework.orm.hibernate3.support.HibernateDaoS C"uahP[Y
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upport; [3/VCYje
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import com.javaeye.common.util.PaginationSupport; dbdM"z4
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public abstract class AbstractManager extends {=:#S+^ER
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HibernateDaoSupport { k%'m *T f
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privateboolean cacheQueries = false; TV59(bG.2
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privateString queryCacheRegion; Fzq41jiS
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publicvoid setCacheQueries(boolean AC%JC+
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cacheQueries){ R3.*dqo$
this.cacheQueries = cacheQueries; {d3<W N
} h:bru:ef
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publicvoid setQueryCacheRegion(String )U
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queryCacheRegion){ D1s4`V -
this.queryCacheRegion = R=j% S!
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queryCacheRegion; s 0u{dqP
} yzsab ^]
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publicvoid save(finalObject entity){ wNJzwC&iQ
getHibernateTemplate().save(entity); <W)u{KS#TY
} X|LxV]
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publicvoid persist(finalObject entity){ W;6vpPhg#!
getHibernateTemplate().save(entity); 25y6a|`
} 5II(mSg8
K*-@Q0"KM{
publicvoid update(finalObject entity){ d(`AXyw
getHibernateTemplate().update(entity); (oz$B0HO:
} Lv[OUW#S
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publicvoid delete(finalObject entity){ F/d7q%I
getHibernateTemplate().delete(entity); ~X(UcZ2
} g| <wyt[
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publicObject load(finalClass entity, u6u=2
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finalSerializable id){ J8a*s`ik
return getHibernateTemplate().load G_H?f\/
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(entity, id); D('2p8;2"7
} pv!oz2w1
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publicObject get(finalClass entity, `Hx~UH)
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finalSerializable id){ BI?@1q}:
return getHibernateTemplate().get )jrT6x^IB
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(entity, id); f$HH:^#
} J
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publicList findAll(finalClass entity){ CI:^\-z
return getHibernateTemplate().find("from rX7QbAB
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" + entity.getName()); 9Mp$8-=>7
} s pLZ2]A
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publicList findByNamedQuery(finalString RPnRVJ&"Z
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namedQuery){ n(nBRCG)o
return getHibernateTemplate 2f`nMW
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().findByNamedQuery(namedQuery); 3l<S}k@M)
}
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publicList findByNamedQuery(finalString query, ]&~]#vB#
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finalObject parameter){ ,bE$| x'
return getHibernateTemplate Si9Z>MR
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().findByNamedQuery(query, parameter); <mMTD8Sx]
} 5Ky#GuC
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publicList findByNamedQuery(finalString query, l=N2lHU
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finalObject[] parameters){ /"H`.LD.?
return getHibernateTemplate vKwQXR~C
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().findByNamedQuery(query, parameters); 2jsw"aHW
} ;Yfv!\^ |
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publicList find(finalString query){ ,B&fFis
return getHibernateTemplate().find <WXzh5D2
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(query); _{vkX<s
} :M{Y,~cP
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publicList find(finalString query, finalObject `u!l3VZ/4
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parameter){ GT hL/M
return getHibernateTemplate().find n26Y]7N
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(query, parameter); j#~Jxv%n
} 5 )2:stT73
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public PaginationSupport findPageByCriteria 0U/K7sZ
_ 7PMmW@
(final DetachedCriteria detachedCriteria){ Glq85S
return findPageByCriteria &bqT/H18
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); kpbm4t
} m|=Ecu
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public PaginationSupport findPageByCriteria -S,ln
;
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(final DetachedCriteria detachedCriteria, finalint ;Z j]~|
k *R<,
startIndex){ M@P1, Y
return findPageByCriteria ]J9cVp
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(detachedCriteria, PaginationSupport.PAGESIZE, ?6c-7QV
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startIndex);
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} ;v17K
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public PaginationSupport findPageByCriteria %8aC1x
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(final DetachedCriteria detachedCriteria, finalint iDl;!b&V.
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pageSize, 2;L|y._`w
finalint startIndex){ {Z; jhR,
return(PaginationSupport) p
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getHibernateTemplate().execute(new HibernateCallback(){ dk
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publicObject doInHibernate e@@?AB$n(
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(Session session)throws HibernateException { Ub0/r$]DK
Criteria criteria = O_$dI*RK
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detachedCriteria.getExecutableCriteria(session); syx\gz
int totalCount = M:Er_,E
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((Integer) criteria.setProjection(Projections.rowCount nfb]VN~(
}MR1^
()).uniqueResult()).intValue(); `=#01YX[0
criteria.setProjection ?EMK8;
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(null); $=sXAK9
List items = ;E~4)^
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criteria.setFirstResult(startIndex).setMaxResults -]Cc
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(pageSize).list(); h9$ Fx
PaginationSupport ps =
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new PaginationSupport(items, totalCount, pageSize, fsO9EEn7X
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8}
startIndex); BhpOXqg
return ps; He0=-AR8
} O^LTD#}$a)
}, true); m,3er*t{
} {-9jm%N
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public List findAllByCriteria(final Q8p&Ki;i
,!G{5FF8:
DetachedCriteria detachedCriteria){ 2^~<("+w
return(List) getHibernateTemplate t<uYM
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().execute(new HibernateCallback(){ ZWc+),X
publicObject doInHibernate 0uVv<Q~
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(Session session)throws HibernateException { F}Mhs17!|
Criteria criteria = @#+jMV$g
*, Ld/O;s
detachedCriteria.getExecutableCriteria(session); {s,+^7
return criteria.list(); I4H`YOD%
} PZ:u_*Vu`
}, true); XA0(f*
} 9D@$i<D:
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public int getCountByCriteria(final W!$zXwY}(
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DetachedCriteria detachedCriteria){ maMHZ\Q
Integer count = (Integer) z^*
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getHibernateTemplate().execute(new HibernateCallback(){ Hyk'c't_O
publicObject doInHibernate 1F[L"W;r
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(Session session)throws HibernateException { iY[+Ywh
Criteria criteria = =<f-ob8,
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detachedCriteria.getExecutableCriteria(session); }pNX@C#De
return n_[i0x7#
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criteria.setProjection(Projections.rowCount X[C3&NX#_
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()).uniqueResult(); xc
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} 9G?ldp8
}, true); _cJ[
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return count.intValue(); yT /EHmJ
} _68BP)nz>.
} dLh6:Gh8_I
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用户在web层构造查询条件detachedCriteria,和可选的 i`U:gw
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 u/^|XOy
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PaginationSupport的实例ps。 7 &)])
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ps.getItems()得到已分页好的结果集 >mu)/kl
ps.getIndexes()得到分页索引的数组 |g)FA_#|<
ps.getTotalCount()得到总结果数 @Z(rgF{{
ps.getStartIndex()当前分页索引 x2wg^$F*oO
ps.getNextIndex()下一页索引 64ox jF)
ps.getPreviousIndex()上一页索引 M8W# io
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Z[#IfbYt
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 M-9gD[m
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一下代码重构了。 zhEo(kU!
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我把原本我的做法也提供出来供大家讨论吧: b](o]O{v
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首先,为了实现分页查询,我封装了一个Page类: Lyoor1
java代码: r'aY2n^O
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/*Created on 2005-4-14*/ Wc'Ehyi;
package org.flyware.util.page; :$H!@n*/R
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/** V/y=6wUiSl
* @author Joa D1"7s,Hmu
* gbGTG(:1S
*/ }B)jq`a?|\
publicclass Page { 1bRL"{m^)-
j7/(sf
/** imply if the page has previous page */ moO_-@i
privateboolean hasPrePage; lizTRVBE
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/** imply if the page has next page */ 1L[S*X
privateboolean hasNextPage; B=zMYi
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/** the number of every page */ D VwCx^
privateint everyPage; Nlt4)
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/** the total page number */ 9*p G?3*I
privateint totalPage; ?0J0Ij,
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/** the number of current page */ u%opY<h
privateint currentPage; ,L%p
(!n-Age
/** the begin index of the records by the current V\zsDP
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query */ q<XcOc5
privateint beginIndex; G%OpO.Wf
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/** The default constructor */ *|'}v[{v^9
public Page(){ g{a d0.y,
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} |Ow$n
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/** construct the page by everyPage r}@< K
* @param everyPage Wf1-"Q
* */ w4}(Ab<Y
public Page(int everyPage){ WguV{#=H
this.everyPage = everyPage; g
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} y Hw!#gWM
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/** The whole constructor */ Na;t#,
public Page(boolean hasPrePage, boolean hasNextPage, ~y%7w5%Un
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int everyPage, int totalPage, gD40y\9r
int currentPage, int beginIndex){ %#Q
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this.hasPrePage = hasPrePage; 9oD#t~+F4
this.hasNextPage = hasNextPage; I)uASfT$
this.everyPage = everyPage; {q2<KRU2+#
this.totalPage = totalPage; Z{16S=0
this.currentPage = currentPage; h=mv9=x
this.beginIndex = beginIndex; m-#d8sD2C
} A3!2"}L
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/** <v-92?
* @return @%7/2k
* Returns the beginIndex. 4w2L?PDMi
*/ *Ag, kW"
publicint getBeginIndex(){ ^f"&}%" M
return beginIndex; ri;r7Y9V9`
} IT7:QEfKU
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/** c'[( d5^|
* @param beginIndex "N]WL5$i
* The beginIndex to set. 3pzOt&T|w
*/ {S# 5g2
publicvoid setBeginIndex(int beginIndex){ _2x uzmz0
this.beginIndex = beginIndex; nFSG<#x\
} m./*LXU
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/** %0go%_
* @return !vi4*
@:
* Returns the currentPage. Y-?51g [u
*/ F\l!A'Q+t
publicint getCurrentPage(){ o<Ke3?J\
return currentPage; D DZTqsws
} J78Qj[v
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/** | H5Ync[s
* @param currentPage agGgJ@
* The currentPage to set. &7JEb]1C
*/ t/_\U=i$
publicvoid setCurrentPage(int currentPage){ oTZo[T@zRx
this.currentPage = currentPage; 6i55J a
} 4ZSfz#<[z
#zh6=.,7
/**
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* @return nau~i1
* Returns the everyPage. 8yNRxiW:
*/ noWRYS %
publicint getEveryPage(){ m3 x!*9h
return everyPage; X:iG[iU*
} OsDp88Bc
jTGS6{E
/** XL%vO#YT
* @param everyPage +;{rU&
* The everyPage to set. ~M|NzK_9
*/ >c~9wv
publicvoid setEveryPage(int everyPage){ Vw6>:l<+<
this.everyPage = everyPage; +^o3}`
} exGhkt~
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/** !M#?kKj
* @return !c3Qcva
* Returns the hasNextPage. w%!k?t,*]
*/ OoA5!HEh
publicboolean getHasNextPage(){ D~t"9Z\
return hasNextPage; 'npT+p$V
} t(LlWd
Y:#kel<
/** {g23[$X]N
* @param hasNextPage 3/#R9J#
* The hasNextPage to set. ]-+.lR%vd9
*/ v{\n^|=])
publicvoid setHasNextPage(boolean hasNextPage){ H@OrX
this.hasNextPage = hasNextPage; .T
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} `i_L?C7
'/n%}=a=
/** Z n"TG/:
* @return 8/kx 3
* Returns the hasPrePage. UH.}B3H
*/ NC[GtAPD3
publicboolean getHasPrePage(){ 9cx!N,R t
return hasPrePage; ,sQ0atk7ma
} V"D<)VVA
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/** ]CtoK%k
* @param hasPrePage +p%5/smfs
* The hasPrePage to set. 6vp8LNSW
*/ Ke;X3j ]`
publicvoid setHasPrePage(boolean hasPrePage){
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this.hasPrePage = hasPrePage; p7ns(g@9
} o sgS?=8
0;m$a=
/** s5Bmv\e.i5
* @return Returns the totalPage. ")[Q4H;V
* Rs(CrB/M
*/ M&BM,~
publicint getTotalPage(){ `__?7"p
)\
return totalPage; #B.w7y5*
} Ubos#hP
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/** P.H/H04+
* @param totalPage |?t8M9[Z
* The totalPage to set. g cK"
*/ 6^z\;,p
publicvoid setTotalPage(int totalPage){ F>oxnhp6
this.totalPage = totalPage; ^xkppN2
} O]r3?=
0)] C&;}_M
} _)Z7Le:f!
D A)0Y_
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|% YzGgp7
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 _*?"[TYfX
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个PageUtil,负责对Page对象进行构造: r/$)c_x`
java代码: 2;(iTPz +
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/*Created on 2005-4-14*/ xS\QKnG.
package org.flyware.util.page; 2Q'XB
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import org.apache.commons.logging.Log; @p` CAB
import org.apache.commons.logging.LogFactory; C.e|VzQa
}ok
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/** /$.vHt5nt
* @author Joa ![D,8]GD
* |ukdn2Q
*/ WyJfF=<
publicclass PageUtil { =O:ek#Bp
> FcA,
privatestaticfinal Log logger = LogFactory.getLog ysT!^-&p
5!Mp#lO
(PageUtil.class); |ij5c@~&
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/** `L[32B9
* Use the origin page to create a new page *]| JX&
* @param page \V-
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* @param totalRecords e%0#"6}
* @return -:p1gg&
*/ f I-"8f0_
publicstatic Page createPage(Page page, int 0]w[wc
<
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totalRecords){ G]DN!7]@g
return createPage(page.getEveryPage(), wQS w&G
^F0jI5j ).
page.getCurrentPage(), totalRecords); i-vJ&}}
} mb`}sTU).
FT<*
/** im[gbac
* the basic page utils not including exception v6Wf7)d/1
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handler !4.^@^L|\
* @param everyPage /2V',0
* @param currentPage qa`(,iN
* @param totalRecords 7Bd_/A($
* @return page V+ ~2q=
*/ 6}lEeMRW
publicstatic Page createPage(int everyPage, int ^52R`{
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currentPage, int totalRecords){ M@[gT?mv1
everyPage = getEveryPage(everyPage); 0]0M>vx
u
currentPage = getCurrentPage(currentPage); ZGvNEjff
int beginIndex = getBeginIndex(everyPage, %=
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'=Y~Ir+
currentPage); `;2`H, G'
int totalPage = getTotalPage(everyPage, B&j+fi
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totalRecords); 1Nu`@)D0
boolean hasNextPage = hasNextPage(currentPage, CnA)>4E*'
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totalPage); JY8pV+q @=
boolean hasPrePage = hasPrePage(currentPage); RA67w&
${eh52)`
returnnew Page(hasPrePage, hasNextPage, wIHz TL
everyPage, totalPage, j".6
currentPage, tV4aUve
{moNtzE;
beginIndex); ,R6$SrNcd
} XKIJ6M~5k
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privatestaticint getEveryPage(int everyPage){ VO?NrKyeW
return everyPage == 0 ? 10 : everyPage; _J;a[Ky+[
} M)Q+_c2*
}CqIKoX.
privatestaticint getCurrentPage(int currentPage){ !Ve3:OZ.nO
return currentPage == 0 ? 1 : currentPage; D8XXm lo
} ZA@"uqa 6b
"
N4]e/.V
privatestaticint getBeginIndex(int everyPage, int }epN<DL
Xxw.{2Ji!q
currentPage){ AOUO',v
return(currentPage - 1) * everyPage; Z] }@#/
n
} 1Xc%%j
&|*|
privatestaticint getTotalPage(int everyPage, int 1!#ZEI C
/RJSkF+!
totalRecords){ -&tiM
v
int totalPage = 0; jX@9849@
,/9|j*9H
if(totalRecords % everyPage == 0) h 42?^mV4?
totalPage = totalRecords / everyPage; (#k#0T kE
else }qPo%T
totalPage = totalRecords / everyPage + 1 ; aH~"hB^e
K.Z{4x=0
return totalPage; 1]~}0;,
} [*v\X %+
dI|/Xm>
privatestaticboolean hasPrePage(int currentPage){ K2Zy6lGOZ
return currentPage == 1 ? false : true; V"73^
} P]GGnT(!
R)z|("%ec
privatestaticboolean hasNextPage(int currentPage, e#^by(1@}
/2 N%Z
int totalPage){ #$E
vybETx
return currentPage == totalPage || totalPage == 8Qh/=Ir
!5-[kG&
0 ? false : true; k=[Ro
} lhU# /}Z
M#m7g4*L !
g&V.o5jIhc
} wDk[)9#A
~MX@-Ff
B^{DCHu/
/^"TMm
;z#9>99rH
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 NR5A"_'
Pcc%VQN
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 j&9~OXYv
F)G#\r
做法如下: ;DTNw=
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 >J1o@0tk
kMA>)\
的信息,和一个结果集List: F
7=-k/k
java代码: kH'Cx^=c6h
}`(kX] ][
foeVjL:T
/*Created on 2005-6-13*/ c/u;v69r
package com.adt.bo; }|d:(*
;S7xJ'H
import java.util.List; T7v8}_"-
T-\,r
import org.flyware.util.page.Page; ,F[mh
>,v~,<3
i
/** /D q]=P
* @author Joa W[jxfZD9v
*/ LLE~V~j
publicclass Result { xl3U
TsD
>m
private Page page; UpITx]y?"m
Dj|S
private List content; 1L0ku@%t9Y
MG6Tk(3S
/** "YBA$ef$
* The default constructor &Fi8@0Fh
*/ {MS&t09Wh
public Result(){ R8KL4g-d
super();
Wi[Y@
} dx~Wm1
W)l&4#__(
/** mH?hzxa+
* The constructor using fields }LRAe3N%8
* Rm
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* @param page 4Vs;Y&t]
* @param content G`n-WP
*/ \bg^E>-
public Result(Page page, List content){ kK(633s
this.page = page; YP7<j*s8
this.content = content; yP-Dj
,
} n5b
N/
aH6pys!O
/** D"hiEz
* @return Returns the content.
4@5<B
*/ #Ky0` n
publicList getContent(){ eD}Ga4
return content; VS`S@+p
} Mk?9`?g.
ex['{|a{
/** pp:+SoyN
* @return Returns the page. 2vwT8/
*/ B<)(7GTv7"
public Page getPage(){ <D=%55
return page; ua{eri[
} WlY%f}ln
^O?$}sr
/** [:o#d`^
* @param content j04Q3d
\f
* The content to set. +,%x&L&I
*/ +V) (,f1
public void setContent(List content){ 9=/8d`r
this.content = content; *f[`Yv
} ^8 z*f&g
0e:aeLh
/** cz0tnF*&
* @param page * T-XslI
* The page to set. &@RU}DnvM&
*/ WgjaMmht
publicvoid setPage(Page page){ n;MoMGnPh,
this.page = page; l/`Z+];
} zJ\I%7h*
} 4jXyA/F9V
VTF),e!
55AG>j&41
PCES&|*rf
|k^X!C 0
2. 编写业务逻辑接口,并实现它(UserManager, 0}ZuF.
O`2%@%?I
UserManagerImpl) rg
$71Ir
java代码: :ortyCB:H
~E)I+$,
:c6%;2
/*Created on 2005-7-15*/ MXhS\vF#m
package com.adt.service; ?GFVV ->i
SVR AkP-
import net.sf.hibernate.HibernateException; y_'8m9Qy)
ljk-xC p/
import org.flyware.util.page.Page; F'"-4YV>&
]\GGC]:\@
import com.adt.bo.Result; dx~F [
Ar\`OhR
/** ^RY_j>i
* @author Joa B
(BWdrG
*/ aWit^dp
publicinterface UserManager { KJ-D|N,8@^
2.|Y
public Result listUser(Page page)throws 9eV@v
gs. K,x ma
HibernateException; Wima=xYe\5
l\S..B
+
} <=0_[M
BKGwi2]Ry
NSx DCTw
"=Ziy4V
d29]R.
java代码: 2Ay2
G-
#$8tBo
Q.5a"(d@
/*Created on 2005-7-15*/ 8sL7p4
package com.adt.service.impl; 04,]upC${W
Hiw{1E:rW
import java.util.List; )`L!eN
y<5s)OehG
import net.sf.hibernate.HibernateException; V57^0^Zp`
j|
257D
import org.flyware.util.page.Page; ;KnnAZJ
import org.flyware.util.page.PageUtil; d`2VbZC`
6~}=? sX4
import com.adt.bo.Result; V+E2nJ
import com.adt.dao.UserDAO; M T{^=F ]
import com.adt.exception.ObjectNotFoundException; YHE7`\l
import com.adt.service.UserManager; T6{IuQjXs
hmks\eb~
/** (}}BZS&.
* @author Joa
^d!-IL_
*/ k8w8I$QEM
publicclass UserManagerImpl implements UserManager { /*st,P$"
rJR"[TTJ
private UserDAO userDAO; f^ nogw<z!
c1Dhx,]ad
/** Yj;$hV8j(
* @param userDAO The userDAO to set. fLPB *y6
*/ QHA<7Wg
publicvoid setUserDAO(UserDAO userDAO){ <~f/T]E,
this.userDAO = userDAO; +8v!vuO'
} &x\u.wIa
_e/vw:
/* (non-Javadoc) tV%M2DxS
* @see com.adt.service.UserManager#listUser V5M_N;h
'|Cs!Zl
(org.flyware.util.page.Page) zX|CW;
*/ b[H& vp
public Result listUser(Page page)throws o^gqpQv
$UKV2c
HibernateException, ObjectNotFoundException { sexnO^s
int totalRecords = userDAO.getUserCount(); $Nnz|y
if(totalRecords == 0) hCc I
>[H5
throw new ObjectNotFoundException Wrt3p-N"D
.~C*7_
("userNotExist"); ~[l2"@
page = PageUtil.createPage(page, totalRecords); {b} ?I4)
List users = userDAO.getUserByPage(page); T|r@:t[
returnnew Result(page, users); fokOjTE
} <?QY\wyikz
0l{').!_
} #;>J<>
ZA+$ZU^
F<
Qjoaz
^[lg1uMW
NhXTt!S6C
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 NC|&7qQ
&A]*"lt|w
询,接下来编写UserDAO的代码: i$$\}2m{L
3. UserDAO 和 UserDAOImpl: $]!uX&
java代码: I3p ~pt2
% ;09J
KhYGiVA
/*Created on 2005-7-15*/ E.t9F3
package com.adt.dao; _~fO8_vr
kjJ\7x6M
import java.util.List; |s[m;Qm[ku
o~ 2bk<]z
import org.flyware.util.page.Page; *!Vic#D%
q$0^U{j/
import net.sf.hibernate.HibernateException; n!A')]y"
`{<2{}2M
/** %t`a-m
* @author Joa ;Hv#SRSz
*/ }ZlJ
publicinterface UserDAO extends BaseDAO { _LxV)
Vt*Duh+4
publicList getUserByName(String name)throws C5*j0}
z@{|Y;s
HibernateException; i=#r JK=
MuO7_*q'n
publicint getUserCount()throws HibernateException; 84cmPnaT
w1h07_u;v
publicList getUserByPage(Page page)throws !f V.#9AB#
e}-uU7O
HibernateException; AW!|xA6'`:
rbqH9 S
} EAqTXB@XU
mv)M9c,`
&:nWZ!D
Hvnak{5
Yono8M;9*
java代码: ^-f5;B`\i
gPd:>$
6JSa:Q>,
/*Created on 2005-7-15*/ -~p@o1k0
package com.adt.dao.impl; bv)E>%Yy
cs8bRXjHa
import java.util.List; 7=6p
rPZ<
import org.flyware.util.page.Page; 3Yp_k
=uYSZR
import net.sf.hibernate.HibernateException; ghx8dX}
import net.sf.hibernate.Query; +[zrU`!@
LyS139P$
import com.adt.dao.UserDAO;
ACU0
Mw\/gm_3
/** ;#G>q o
* @author Joa Sr,ZM1J
*/ +wY3E*hU
public class UserDAOImpl extends BaseDAOHibernateImpl n,9 *!1y
fFqK.^Tn
implements UserDAO { tV[?WA[xt
!,V8?3.aJn
/* (non-Javadoc) a'
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* @see com.adt.dao.UserDAO#getUserByName "k"q)5c
Z@RAdwjR`p
(java.lang.String) @ J!)o d
*/ s3uT:Xw3rW
publicList getUserByName(String name)throws ]zhFFq`
Yc"G="XP;
HibernateException { \@*cj8e
String querySentence = "FROM user in class c_kxjzA#
hkRv0q.'
com.adt.po.User WHERE user.name=:name"; )
ok_"wB
Query query = getSession().createQuery hh |'Uq3
Oa$ew'
(querySentence); B>o#eW
query.setParameter("name", name); n?YGXW/
return query.list(); )m\%L`+
} @Ys(j$U't
~*L H[l>K
/* (non-Javadoc) #v89`$#`2
* @see com.adt.dao.UserDAO#getUserCount() ;k (}~_
*/ vJtQ&,zG
publicint getUserCount()throws HibernateException { 1k-^LdDj
int count = 0; o5BOe1_Pw
String querySentence = "SELECT count(*) FROM 2a (w7/W:
x|F6^d
user in class com.adt.po.User"; Jn'q'+
Query query = getSession().createQuery fx99@%Ii
RgRyo
(querySentence); R)nhgp(~
count = ((Integer)query.iterate().next yXg783B|v
M\enjB7k
()).intValue(); z]gxkol\
return count; ag:#82C
} X.j#??
D<5gdIw
/* (non-Javadoc) i._d^lR\t
* @see com.adt.dao.UserDAO#getUserByPage m&Ms[X
)WwysGkqol
(org.flyware.util.page.Page) CW*6 -q
*/ D7sw;{ns
publicList getUserByPage(Page page)throws G?<L{J2"Q
}1:jM_H)k
HibernateException { Dr7,>Yx
String querySentence = "FROM user in class #y-OkGS
^
unSF;S<
com.adt.po.User"; 0b?9LFd
Query query = getSession().createQuery ugVsp&i#
h+R}O9BD
(querySentence); h&h]z[r R
query.setFirstResult(page.getBeginIndex()) MCz+l0
.setMaxResults(page.getEveryPage()); |pq z(j7
return query.list(); T_5 E
} [EB2o.EsO
$v-lG(
} oYlq1MB?
3j]La
b.8HGt<%
~
Z%>N
%do|>7MO@
至此,一个完整的分页程序完成。前台的只需要调用 v*FCE 1HI
IW6;ZDP
userManager.listUser(page)即可得到一个Page对象和结果集对象 r/:9j(yxr
q^(A6W
的综合体,而传入的参数page对象则可以由前台传入,如果用 I/XVo2Ee
C\$7C5/
webwork,甚至可以直接在配置文件中指定。 xV}|G
b:Rl }"a
下面给出一个webwork调用示例: _.?$~;7
java代码: luat1#~J
Gx'mVC"{
0Zk A.p
/*Created on 2005-6-17*/ |\~cjPX(
package com.adt.action.user; e0v&wSi
*AZC{jP
import java.util.List; 8Ln:y'K
j><.tA~i
import org.apache.commons.logging.Log; ${6 ;]ye
import org.apache.commons.logging.LogFactory; )oAK)e
import org.flyware.util.page.Page; NFmB ^@k
QL_bg:hs
import com.adt.bo.Result; ~|l>bf
import com.adt.service.UserService; (Pvch!
import com.opensymphony.xwork.Action; ]E[Mv}
=
9FcCq*D
/** xjR/K&[m
* @author Joa sI9~TZ :
*/ %ze Sx
publicclass ListUser implementsAction{ CFRo>G
{{@3r5KGl
privatestaticfinal Log logger = LogFactory.getLog ;M@/AAZ
+c\fDVv
(ListUser.class); Q'$aFl'NR
bG2!5m4L
private UserService userService; g>VkQos5"
XK(<N<Z@|e
private Page page; ]9;WM.
Tvf]OJ9N
privateList users; pm3?
T][\wyLx1
/*
k"GW3E;
* (non-Javadoc) mQo]k
* 15Yy&9D
* @see com.opensymphony.xwork.Action#execute() L7a+ #mGE
*/ 3&x_%R
publicString execute()throwsException{ P9X/yZ42
Result result = userService.listUser(page); 2E=E!Zwt_
page = result.getPage(); 9at7$Nq
users = result.getContent(); N
@]*E
return SUCCESS; qC`"<R=GX
} >Pbd#*
)oHIRsr
/** w;>]L.n
* @return Returns the page. Z1^S;#v
*/ u8-)LOf(
public Page getPage(){ vV"TTzs!
return page; 2{@:
:JZ
} 5vg@zH\z
2JtGS-t
/** 7m@pdq5Ub
* @return Returns the users. :~U1JAs$
*/ IxgnZX4N
publicList getUsers(){ F
N(&3Ull
return users; -D{~7&
} 0&-!v?6)
/M B0%6m
/** C+-~Gmrb(7
* @param page a]
>|2JN<&
* The page to set. HTkce,dQ
*/ Es[?yft2Q<
publicvoid setPage(Page page){ %o+bO}/9
this.page = page; B'atwgI0
} H\^5>ccU>V
8>Ervi`
/** 1pO ;aG1O
* @param users 0#sk ]Qz
* The users to set. 'HW(RC0dR
*/ -v >BeVF
publicvoid setUsers(List users){ .- c3f1i
this.users = users; =eTI@pN`
} i!YZF$|
vAwFPqu
/** q)<5&|V
* @param userService MH{vFA4:,
* The userService to set. ukq9Cjs
*/ g<}EL[9[J
publicvoid setUserService(UserService userService){ Me5umA
this.userService = userService; Yg2z=&p-{"
} b^hCm`2w*
} 3]xnKb|W
\+L_'*&8
.$v]Bxu
7b@EvW6X}
'{6`n5:e
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, a;/4 ht
|[k6X=5
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 JJ qX2B
Zb);08X
么只需要: ?xUz{O0/
java代码: HzH_5kVW
;M4N=G Wd4
>+,1@R
<?xml version="1.0"?> V~e1CZ(2X
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork <| Z0|sel
GXJ3E"_.
1.0//EN" "http://www.opensymphony.com/xwork/xwork- PMXnupt
l\$_t2U
1.0.dtd"> #)cRD#0
b;!ilBc
<xwork> K7e<hdP_#
:GL|:
<package name="user" extends="webwork- _;LHC;,:
e$F7wto
interceptors"> {6/%w,{,
.=^h@C*
<!-- The default interceptor stack name (7Y :3
7M*+!al9
--> iCv &<C@
<default-interceptor-ref bIWcL$}4Q
0Vy*
0\{S
name="myDefaultWebStack"/> S@_@hFV jd
\?qXscq
<action name="listUser" *'exvY~
I X\&