Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 k*Kq:$9"
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ))N^)HR
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 mx yT==E
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 Fk43sqU6~
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分页支持类: s"/8h#!zv
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java代码: A@]
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package com.javaeye.common.util; QbWD&8T0O
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import java.util.List; ){}#v&
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publicclass PaginationSupport { d~8Q)"6 [
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publicfinalstaticint PAGESIZE = 30; }bVyvH
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privateint pageSize = PAGESIZE; tv2dyC&a
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privateList items; SYL$?kl
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privateint totalCount;
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privateint[] indexes = newint[0]; BzZy s
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privateint startIndex = 0; '54@-}D
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public PaginationSupport(List items, int BSz\9 eT
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totalCount){ -=RXhE_{
setPageSize(PAGESIZE); 2g$Wv :E3
setTotalCount(totalCount); K6X1a7
setItems(items); j405G4BVW
setStartIndex(0); NJp;t[v.^
} FueJe/~t
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public PaginationSupport(List items, int y^
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[{ pc1U-
totalCount, int startIndex){ BK{8\/dg
setPageSize(PAGESIZE); .^uu*S_
setTotalCount(totalCount); (<CLftQKg
setItems(items); ~(8A&!#,!
setStartIndex(startIndex); 8C2t0u;Y
.
} (GV6%l#I
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public PaginationSupport(List items, int 4c% :?H@2
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totalCount, int pageSize, int startIndex){ =mZw71,
setPageSize(pageSize); /vMpSN|3
setTotalCount(totalCount); g#AA.@/Z
setItems(items); |] YT6-?.
setStartIndex(startIndex); (xTHin$
} $Z j.
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publicList getItems(){ A1C@'9R*
return items; LF0~H}S;6B
} vV|egmw01
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publicvoid setItems(List items){ 5HU>o|.
this.items = items; 2{&" 3dq
} J4gIkZD
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publicint getPageSize(){ yE7pCgXt
return pageSize; Np<Aak
} ^Z!W3q Q
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publicvoid setPageSize(int pageSize){ B}(YD;7vJ
this.pageSize = pageSize; FD*y[A
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} =k_u5@.Z
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publicint getTotalCount(){ Xy{b(b;9
return totalCount; mVkn~LD:0
} =4I361oMf
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publicvoid setTotalCount(int totalCount){ 6Z"%vrH
if(totalCount > 0){ Wp'\NFe8
this.totalCount = totalCount; D >mLSh
int count = totalCount / ;f><;X~KX
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pageSize; TKE)NIa
if(totalCount % pageSize > 0) 2/~v
count++; p+t8*lkq
indexes = newint[count]; {T IGPK
for(int i = 0; i < count; i++){ i~2>kxf;K1
indexes = pageSize * t@ Jo ?0s
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i; \u*,~J)z
} !y),| #7P
}else{ %:y-"m1\u$
this.totalCount = 0; NE! Xt <A
} +)Ty^;+[1
} YT_kMy>
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publicint[] getIndexes(){ 2vXMrh\
return indexes; 3.jwOFH$
} LDNpEX~
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publicvoid setIndexes(int[] indexes){ Qknd ^%
this.indexes = indexes; QIw.`$H+
} aql*@8
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publicint getStartIndex(){ ;)kBJ @
return startIndex; 2P|-V} ;9
} ~vXul`x
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publicvoid setStartIndex(int startIndex){ J7xZo=@k
if(totalCount <= 0) x:2_FoQ
this.startIndex = 0; BgRiJFa.d[
elseif(startIndex >= totalCount) ''6"Xi|5
this.startIndex = indexes +vuW9
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[indexes.length - 1]; ;?cUF78#
elseif(startIndex < 0) VcP#/&B|
this.startIndex = 0; l9Vim9R5T
else{ Ax\Fg
5
this.startIndex = indexes %cv%u6 b
5
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[startIndex / pageSize]; -LY_7Kg
} ^TjFR*S'E
} <omz9d1
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publicint getNextIndex(){ c{<3\
int nextIndex = getStartIndex() + |joGrWv4
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pageSize; GwvxX&P
if(nextIndex >= totalCount) J
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return getStartIndex(); 4$J/e?i
else QSLDA`
return nextIndex; w\M_3}
} WsoB!m
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publicint getPreviousIndex(){ Nr)(&c8
int previousIndex = getStartIndex() - 1Zecl);O{
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pageSize; ,Q:dAe[ZsX
if(previousIndex < 0) _#+9)*A
return0; .{}t[U
else 2 rH6ap
return previousIndex; AE$)RhY`
} lojn8uL
2.[qcs3zl
} DXiD>1(q
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抽象业务类 gV7o
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java代码: q8D1MEBL`
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/** qvscf_%FM
* Created on 2005-7-12 '=2t(@aC
*/ U".-C`4v
package com.javaeye.common.business; c;e,)$)-|
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import java.io.Serializable; w"e2}iE7
import java.util.List; +!<`$+W
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import org.hibernate.Criteria; k9,"`dk@
import org.hibernate.HibernateException; Y}6)jzBV
import org.hibernate.Session; Xu$*ZJ5w
import org.hibernate.criterion.DetachedCriteria; aZ^lI
6@+4
import org.hibernate.criterion.Projections; ^>"?!lv
import :b=0_<G
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org.springframework.orm.hibernate3.HibernateCallback; ob;oxJ@[c
import %(]rc%ry0
BE2{qO{
org.springframework.orm.hibernate3.support.HibernateDaoS N3?d?+A$
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upport; jyC6:BNust
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import com.javaeye.common.util.PaginationSupport; IF}r%%'Y$
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public abstract class AbstractManager extends n >Ei1
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HibernateDaoSupport { 8a h]D
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privateboolean cacheQueries = false; OTm`i>rB
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privateString queryCacheRegion; 4D13K.h`O
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publicvoid setCacheQueries(boolean BCbW;w8aI
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cacheQueries){ ra&C|"~E
this.cacheQueries = cacheQueries; %F~
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} ~IXfID!8
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publicvoid setQueryCacheRegion(String j{=%~
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queryCacheRegion){ `et<Z
this.queryCacheRegion = *v9G#[gG
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queryCacheRegion; :-Pj )Y{I
} 8M|Q^VeT,1
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publicvoid save(finalObject entity){ vEsSqzc
getHibernateTemplate().save(entity); \9p;md`
} 6yb<4@LOb
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publicvoid persist(finalObject entity){ */)gk=x8
getHibernateTemplate().save(entity); EkX6> mo
} 0#JBz\
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publicvoid update(finalObject entity){ QZlUUj\
getHibernateTemplate().update(entity); 6D0,ME#
} G!\xc
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publicvoid delete(finalObject entity){ }dz(DPd
getHibernateTemplate().delete(entity); b\2"1m0H
} F0\ry "(t
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publicObject load(finalClass entity, =FnZk J
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finalSerializable id){ S6mmk&n
return getHibernateTemplate().load | QA8"&r
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(entity, id); <G>PPf}
} N[-)c,O
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publicObject get(finalClass entity, 7h2bL6Y88
<c#[.{A}s
finalSerializable id){ zCrcCr
return getHibernateTemplate().get 9:>K!@
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(entity, id); 2. _cEY34
} (R-Q9F+;
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publicList findAll(finalClass entity){ je-s%kNlJ
return getHibernateTemplate().find("from 7 SZR#L
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" + entity.getName()); m!_ghD{5h
} GN0'-z6Uy
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publicList findByNamedQuery(finalString 0^[6
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namedQuery){ JyO lVs<T
return getHibernateTemplate 7%"7Rb^@
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().findByNamedQuery(namedQuery); 3:Wr)>l}#
} gwJu&HA/
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publicList findByNamedQuery(finalString query, P vwIO_W
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finalObject parameter){ SO/]d70HG
return getHibernateTemplate pZxL?N!
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().findByNamedQuery(query, parameter); *q{UipZbx
} $Stu-l1e a
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publicList findByNamedQuery(finalString query, OB22P%
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finalObject[] parameters){ 0
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return getHibernateTemplate 7p6J
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().findByNamedQuery(query, parameters); RZA\-?cO)
} 8BDL{?Mu
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publicList find(finalString query){ |T *qAJ8c
return getHibernateTemplate().find R:N-y."La.
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(query); [[Z>(d$8
} TzGm562o%
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publicList find(finalString query, finalObject (_ah~VnO
'.,.F0{x
parameter){ xQap44KPZ
return getHibernateTemplate().find u2-7vudh
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(query, parameter); :g#it@
} Z;D3lbqE
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public PaginationSupport findPageByCriteria "~C#DZwt{
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(final DetachedCriteria detachedCriteria){ vWs c{9
return findPageByCriteria (}1f]$V
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); VY@hhr1s~
} g/p9"eBpq
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public PaginationSupport findPageByCriteria %PbqASm
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(final DetachedCriteria detachedCriteria, finalint y#;VGf6lj
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startIndex){ W+e*(W|d6
return findPageByCriteria TZNgtR{q
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(detachedCriteria, PaginationSupport.PAGESIZE, }c ;um
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startIndex); +t4m\/y
} DAHf&/JK
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public PaginationSupport findPageByCriteria &> .1%x@R
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(final DetachedCriteria detachedCriteria, finalint :b*`hWnQ
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pageSize, z.&%>%TPP
finalint startIndex){ N09+id g
return(PaginationSupport) Mk/!,N<h#
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getHibernateTemplate().execute(new HibernateCallback(){ )=nPM`Jn.
publicObject doInHibernate !r
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(Session session)throws HibernateException { Juqn
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Criteria criteria = ~PW}sN6ppG
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detachedCriteria.getExecutableCriteria(session); <<5 :zlb
int totalCount = Sx9:$"3.X
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((Integer) criteria.setProjection(Projections.rowCount :;q_f+U
.y9rM{h}b
()).uniqueResult()).intValue(); fhIj+/{_O
criteria.setProjection /3Ix,7
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(null); U4l*;od
List items = PJ'lZu8?x
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criteria.setFirstResult(startIndex).setMaxResults 3(})uV
ivz?-X4]
(pageSize).list(); w<>6>w@GZ
PaginationSupport ps = wU)5Evp[
S{i@=:
new PaginationSupport(items, totalCount, pageSize, bSR+yr'?
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startIndex); _% 9+U[@
return ps; ) v5n "W
} 7h9[-d6
}, true); 4O_+4yS
} 3r:)\E+Q_
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public List findAllByCriteria(final :8Ts'OGwI
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DetachedCriteria detachedCriteria){ Xe3z6
return(List) getHibernateTemplate `}8@[iB'
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().execute(new HibernateCallback(){ maUHjI
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publicObject doInHibernate }42qMOi#w1
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(Session session)throws HibernateException { <Z:8~:@
Criteria criteria = %>9+1lUhV
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detachedCriteria.getExecutableCriteria(session); 9#T%bB"J
return criteria.list(); ?V)C9@bp
} 1;:t~Y
}, true); nR@,ouB-$
} +>:_kE]?nX
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public int getCountByCriteria(final ?I2k6%a
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DetachedCriteria detachedCriteria){ Fr3d#kVR
Integer count = (Integer) pG F5aF7T
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getHibernateTemplate().execute(new HibernateCallback(){ x"llX
publicObject doInHibernate g[wP!y%V
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(Session session)throws HibernateException { DPS1GO*
Criteria criteria = J={OOj
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detachedCriteria.getExecutableCriteria(session); /=YqjZTCq
return B#k3"vk#
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criteria.setProjection(Projections.rowCount '
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()).uniqueResult(); s 9|a2/{
} @Tfwh/UN
}, true); |
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return count.intValue(); j`|^s}8t
} Ld}(*-1i
} Fi?Q
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用户在web层构造查询条件detachedCriteria,和可选的 6a%:zgkOpu
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 )`s;~_ZZ
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PaginationSupport的实例ps。 !M]%8NTt2
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ps.getItems()得到已分页好的结果集 o[6vxTH
ps.getIndexes()得到分页索引的数组 Q@e*$<3
ps.getTotalCount()得到总结果数 /nY).lSH
ps.getStartIndex()当前分页索引 e>,9]{N+$
ps.getNextIndex()下一页索引 9QOr,~~s
ps.getPreviousIndex()上一页索引 iFnOl*TC
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 M2;%1^
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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 |B%BwE
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一下代码重构了。 x5fgF;
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我把原本我的做法也提供出来供大家讨论吧: RP~vB#}
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首先,为了实现分页查询,我封装了一个Page类: J@ktj(
java代码: Z:UgozdC
192 .W+H<
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/*Created on 2005-4-14*/ )BF \!sTn
package org.flyware.util.page; u>,lf\Fgz
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/** g{A3W) [ b
* @author Joa <ELziE~>V
* <TLGfA1bC
*/ &\"Y/b]
publicclass Page { !B [1zE
]r/(n]=(
/** imply if the page has previous page */ ~A[YnJYA#
privateboolean hasPrePage; 8/Et&TJ`
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fqM
/** imply if the page has next page */ aQ!9#d_D
privateboolean hasNextPage; C3
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/** the number of every page */ Wj&<"Z6'm(
privateint everyPage; k_*XJ <S!Y
VO.-.
/** the total page number */ Ynv9&P
privateint totalPage; lFiq<3Nk
/,1SE(
/** the number of current page */ hi ;WFyJTu
privateint currentPage; <CNE>@-f
4NpHX+=P
/** the begin index of the records by the current T>\nWancQM
%PQldPL8
query */ u;+%Qh
privateint beginIndex; ?G4iOiyt
",~ b2]ym
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/** The default constructor */ o5N]((9
public Page(){ 0M#N=%31
dr|| !{\
} CDQJ bvx
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/** construct the page by everyPage \yih 1Om>~
* @param everyPage U9<_6Bsd
* */ gq
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public Page(int everyPage){ l9_m>X~
this.everyPage = everyPage; ?)!Sm N/
} F1 <489
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/** The whole constructor */ H/^~<U#p
public Page(boolean hasPrePage, boolean hasNextPage, _, \y2&KT
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5*JV )[
int everyPage, int totalPage, {[Uti^)m%
int currentPage, int beginIndex){ /yx=7<
this.hasPrePage = hasPrePage; CCuxC9i7
this.hasNextPage = hasNextPage; Rz`@N`U
this.everyPage = everyPage; v\fzO#vj
this.totalPage = totalPage; gXq!a|eH
this.currentPage = currentPage; k k
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this.beginIndex = beginIndex; @
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} H,(F1+~d
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/** -`-ACWeNV
* @return +DicP"~*
* Returns the beginIndex. gb]hOB7g
*/ @kwLBAK}@
publicint getBeginIndex(){ aN>U. SB
return beginIndex; $|Q".dD
} S#P+B*v
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/** ~J%R-{U9
* @param beginIndex |tG05 +M
* The beginIndex to set. D4AEZgC F,
*/ IgLVn<5n
publicvoid setBeginIndex(int beginIndex){ nped
this.beginIndex = beginIndex; lN);~|IOv7
} PASuf.U$"
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/** nA>*IU[
* @return p:Iw%eZ:
* Returns the currentPage. w|&,I4["
*/ :0B
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publicint getCurrentPage(){ |$M@09,F"
return currentPage; !-KCFMvT
} '!pAnsXfO
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/** 63.( j P1;
* @param currentPage gB>(xY>LrA
* The currentPage to set. n49;Z,[~
*/ Mg#`t$u
publicvoid setCurrentPage(int currentPage){ +VwV5iy[`
this.currentPage = currentPage; D`V6&_.p
} SrSG{/{
y= 2=DU
/** 5RW@_%C
* @return s5Pq$<
* Returns the everyPage. *f{7
*/ g+igxC}2z
publicint getEveryPage(){ /d[Mss
return everyPage; 7`Qde!+C
} >+L7k^[,0
|Es0[cU
/** U> W|(Y
* @param everyPage m[8IEKo
* The everyPage to set. 5$anqGw
*/ $?-7OXj<
publicvoid setEveryPage(int everyPage){ HB%K|&!+
this.everyPage = everyPage; ]Fxku<z7|
} HHZ`%
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/** KrS
* @return c2/"KT
* Returns the hasNextPage. j]AekI4I
*/ ?'Cb-C_
publicboolean getHasNextPage(){ hMv2"V-X
return hasNextPage; Ocyb c%
} V>6QPA^
B<Ol+)@,}
/** qbH%Hx
* @param hasNextPage U4]30B{;H
* The hasNextPage to set. X)8e4~(?
*/ |ribWCv0
publicvoid setHasNextPage(boolean hasNextPage){ L,#^&9bHa#
this.hasNextPage = hasNextPage; en%J!<&W{K
} >#INEO
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/** ;r3}g"D@
* @return )Q~C4 C-j
* Returns the hasPrePage. xF&6e&nv
*/ \/n+j!
publicboolean getHasPrePage(){ 7vw;Egd@@-
return hasPrePage; ~)_K"h.DY
} 2.ew^D#
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/** Vu=] O/ =P
* @param hasPrePage $_wo6/J5+D
* The hasPrePage to set. {aoMJJq
*/ 0fA=_=A,
publicvoid setHasPrePage(boolean hasPrePage){ B&
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this.hasPrePage = hasPrePage; 04~}IbeJ
} u
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/** w#sq'vo4%
* @return Returns the totalPage. ;ed#+$Na
* w;~>k%}j
*/ r|<6Aae&
publicint getTotalPage(){ r5[4h'f
return totalPage; 6s5yyy=L%~
} +^Fp&K+^
X
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/** ;>8kPG
* @param totalPage vmLpmxS
* The totalPage to set. Vu%n&uF
*/ YKY2Cw
publicvoid setTotalPage(int totalPage){ rmsQt
this.totalPage = totalPage; 0 k9<&
} q~j)W$k
se#@)LtZ
} MF^_Z3GS'
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VNO'="U
\X5 3|Y;=
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 ';Nu&D#Ph
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个PageUtil,负责对Page对象进行构造: 1 =^
java代码: sCkO0dl8
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/*Created on 2005-4-14*/ JYQ.EAsr!
package org.flyware.util.page; )nOE8y/
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import org.apache.commons.logging.Log; F{\=PCZ>7
import org.apache.commons.logging.LogFactory; @y5= J`@=
0yaMe@&,
/** 57<Di!rt
* @author Joa x}|+sS,g
* /kRAt^4!
*/ ^&NN]?
publicclass PageUtil { e8-ehs>
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privatestaticfinal Log logger = LogFactory.getLog }vY.EEy!
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(PageUtil.class); @D]lgq[
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/** C `6S}f,
* Use the origin page to create a new page Mb.4J2F ?
* @param page H{%H^t>
* @param totalRecords T
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* @return *{|$FQnR>(
*/ oqYt/4^Q
publicstatic Page createPage(Page page, int ceG&,a$\
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totalRecords){ 'g hys1H
return createPage(page.getEveryPage(), VX!hv`E
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page.getCurrentPage(), totalRecords); /tZ0
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} -?z\5z
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/** JD*8@N
* the basic page utils not including exception N2Ssf$
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handler = ^s$
<
* @param everyPage c0ZaFJ
* @param currentPage N&m_e)E5c
* @param totalRecords 5gshKmt_
* @return page )~dOmfw%|
*/ PS}73Y#
publicstatic Page createPage(int everyPage, int {OP~8e"
'yr{^Pek
currentPage, int totalRecords){ ~b6GrY"vB
everyPage = getEveryPage(everyPage); O:YJ%;w
currentPage = getCurrentPage(currentPage); ZLrHZhP-+
int beginIndex = getBeginIndex(everyPage, GW/WUzK
(:7a&2/M
currentPage); ]]PE#DDg
int totalPage = getTotalPage(everyPage, \z:<DsQ&
CN\=9Rvs
totalRecords); yb?|Eww_o
boolean hasNextPage = hasNextPage(currentPage, l'uOORI
$8g42LR'
totalPage); `tVy_/3(9
boolean hasPrePage = hasPrePage(currentPage); UP8{5fx'
U=QA e
returnnew Page(hasPrePage, hasNextPage, w
&
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everyPage, totalPage, ]\dHU.i
currentPage, t^U^Tr
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beginIndex); 2y%R:Mu
} BIj
c\K<sM{
privatestaticint getEveryPage(int everyPage){ $>r5>6
return everyPage == 0 ? 10 : everyPage; :)4*^a/lC
} U&W"Ea=R/
`0@z"D5c
privatestaticint getCurrentPage(int currentPage){ YlKFw|=
return currentPage == 0 ? 1 : currentPage; Y.-S=Y
} T5e^J"
W;TJenv
privatestaticint getBeginIndex(int everyPage, int H1&RI4XC
[.-a$J[4+F
currentPage){ ag;dc
return(currentPage - 1) * everyPage; FN\GE\H
} kOI
!~Qk
"dtlME{Bx
privatestaticint getTotalPage(int everyPage, int %/pc=i|+
Nw pS)6<-
totalRecords){ 1EsqQz*$u
int totalPage = 0; S{:Cu}o
^P$7A]!
if(totalRecords % everyPage == 0) HeozJ^u\?
totalPage = totalRecords / everyPage; r?3Aqi"
else Yqj+hC6>,
totalPage = totalRecords / everyPage + 1 ; B9#;- QO
~kb{K;
return totalPage; PeNF+5s/K
} >];"N{ A
S>t>6&A
privatestaticboolean hasPrePage(int currentPage){ OZOb1D
return currentPage == 1 ? false : true; [r9d<Zi}{
} nzuF]vo
xS+rHC
privatestaticboolean hasNextPage(int currentPage, ~Z/7pP+
"%
Y u
wMY
int totalPage){ u"Fjw F?
return currentPage == totalPage || totalPage == "b%FmM
A*i_|]Q
0 ? false : true; :Ss3ck*=
} 1;&T^Gdj
nk/vGa4
D=&K&6rr
} ?,XC=}
9@y3IiZ"}
6+PGwCS
W[|[;{
yL&/m~{s
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 _yVPpA[a
4f {+pf^R
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 RL&lKHA
}0{B
做法如下: ~gdd cTp
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 'n4u-pM(nB
I7G,`h+H
的信息,和一个结果集List: xZ+]QDKC
java代码: @O/,a7Tt
T|bZ9_?+2
Xw^X&Pp
/*Created on 2005-6-13*/ "&-C$J5
Id
package com.adt.bo; uvv.WbZ
,Rz}=j
import java.util.List; o;QZe&
SdI1}&
import org.flyware.util.page.Page; P4 6,o
~ 5"J(
/** L_?$ayZ;
* @author Joa a5V=!OoMk
*/ o5 WW{)Q
publicclass Result { _9kIRmT{
Tl3"PIb
private Page page; 6K 4+0xXv
YoAg
private List content; f:vD`Fz1
5\S&)ZA@
/** bU+9Gi@v
* The default constructor tIGs>, a=
*/ M&[b.t*
public Result(){ F$yeF^\g
super(); [Vp\$;\nT
} Le&;g4%
T 2|:nC)@
/** ML=z<u+
* The constructor using fields ^:z7E1~
* 9h&yuS'Yj
* @param page NvHN -^2
* @param content X9~p4ys9{
*/ {^m5#f 0"
public Result(Page page, List content){ P(;Mb{
this.page = page; ]o*$h$? s
this.content = content; %nQmFIt
} %3G;r\|r]
P)1EA;
/** HNMBXXf,B
* @return Returns the content. 6"%2,`Nu
*/ \h#9oPy
publicList getContent(){ sHs g_6~
return content; !Uy>eji}
} e1^l.>2d6
uV77E*+7\
/** +c?ie4
* @return Returns the page. 7K :FeW'N
*/ -tyaE
public Page getPage(){ r*Z_+a8
return page; xwOE+
} 0b++17aV
5hz_P+Q
/** P`
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* @param content \Tkp
* The content to set. PbEQkjE
*/ bA*"ei+!
public void setContent(List content){ J6auUm` `
this.content = content; 4J}3,+
} L[. <o{
rr )/`Kmv%
/** !I7 ?
* @param page %zflx~
* The page to set. OG}KqG!n
*/ 1eiw3WU;
publicvoid setPage(Page page){ -0DZ::
this.page = page; FG#nap{
} hS_.l}0yf
} iT$d;5_pU
8&?p
BS.=
C P&o%Uc*
)_Iz>)
2. 编写业务逻辑接口,并实现它(UserManager, {aIZFe}B
3'^S3W%
UserManagerImpl) b9#m m
java代码: acae=c|X
}.t^D|
^O \q3HA_4
/*Created on 2005-7-15*/ :D4];d>1
package com.adt.service; 8]]@S"ZM,\
Tzf$*Uje3
import net.sf.hibernate.HibernateException; 8_X.c
xT=ySa$|>
import org.flyware.util.page.Page; TrQm]9 @
^'YHJEK
import com.adt.bo.Result; r0u J$/!
1tyNRoET
/** rXDJ:NP
* @author Joa
@ExLh9
*/ zzE]M}s
publicinterface UserManager { b"3uD`
y($EK(cb
public Result listUser(Page page)throws 3P`WPph
G<fS(q
HibernateException; 6VFirLd
=h7[E./U1
} |?yE^$a
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Rdj8*f
?sE@]]z
{83C,C-
java代码: O!,Ca1N
C$_G'XI
8=pv/o
/*Created on 2005-7-15*/ n{$}#NdV
package com.adt.service.impl; ?-S8yqe
wA1Ey:q
import java.util.List; XD
5n]AL
OOfyGvs
import net.sf.hibernate.HibernateException; []=_<]{
<OIUyZS
import org.flyware.util.page.Page; }1,'rmT
import org.flyware.util.page.PageUtil; l-cW;b~
!YY6o
V
import com.adt.bo.Result; {dBB{.hX
import com.adt.dao.UserDAO; ^8Z@^M&O"
import com.adt.exception.ObjectNotFoundException; uct=i1+ fE
import com.adt.service.UserManager; y]7%$*
<
jQ)L pjS1
/** U Q)!|@&
* @author Joa /Bh>
*/ HS(U4
publicclass UserManagerImpl implements UserManager { F:S"gRKz
^?nP$+gq
private UserDAO userDAO; !*5_pGe
!"`Jqs
/** u?H@C)P
* @param userDAO The userDAO to set. C_-%*]*,j
*/ 7oD
y7nV4
publicvoid setUserDAO(UserDAO userDAO){ 6N&|2: U
this.userDAO = userDAO; ovB=Zm
} Y}S.37|+^
f&f`J/(
/* (non-Javadoc) 9QC< E|
* @see com.adt.service.UserManager#listUser D(!;V
KH
O%52V|m}{
(org.flyware.util.page.Page) *^uGvJXF
*/ :Jm!=U%'Z
public Result listUser(Page page)throws 3Fgz)*Gu]
)U]:9)
HibernateException, ObjectNotFoundException { %n4@[fG%K
int totalRecords = userDAO.getUserCount(); +;YE)~R?
if(totalRecords == 0) vUqe.?5
throw new ObjectNotFoundException 4Q@\h=r
b'&LBT7
("userNotExist"); IeH^Wm&^
page = PageUtil.createPage(page, totalRecords); `|&\e_"DE
List users = userDAO.getUserByPage(page); s:3aRQ%
returnnew Result(page, users); g%ZdIKj!
} Bj; [
UmYD]
} 1E8$% 6VV
/9P^{OZ;y
A0S8Dh$
6={IMkmA
RXUA!=e
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 7,f:Qi@g
Ndo}Tk!
询,接下来编写UserDAO的代码: `(P
"u
3. UserDAO 和 UserDAOImpl: $y8mK|3.3u
java代码: o1Ne+Jt
cD5w| rm?i
ES^NBI j5P
/*Created on 2005-7-15*/ EN)YoVk
package com.adt.dao; KuIkul9^%
93 [rL+l.Y
import java.util.List; y2U/$%B)G
:2 _0L
import org.flyware.util.page.Page; =n)JJS94
EK^JLvyT
import net.sf.hibernate.HibernateException; s;anP0-O
UVz=QEuYb
/** =sxkr ih
* @author Joa J0&zb'1
*/ Tc9&mKVE%(
publicinterface UserDAO extends BaseDAO { ,?Ok[G!cm
$I\))*a
publicList getUserByName(String name)throws d:A\<F
+d.u##$
HibernateException; _L8Mpx*E
C(f$!~M4b
publicint getUserCount()throws HibernateException; _c[|@D
G!nl'5|y
publicList getUserByPage(Page page)throws mp!YNI
3Wjq >\
HibernateException; km9Gwg/zT
SRP5P,- y
} nWKO8C>
hT.4t,wa8
EV:_Kx8f P
Vp|2w lFE-
JtSuD>H`"
java代码: r;c' NqP
~o:rM/!Ba
=s`XZkh
/*Created on 2005-7-15*/ ,?C|.5
package com.adt.dao.impl; &/ \O2Aw8
CR%D\I$o
import java.util.List; c$@`P
d,zp`S
import org.flyware.util.page.Page; VEL:JsY
FX{~"
import net.sf.hibernate.HibernateException; " ]aQ Hh]f
import net.sf.hibernate.Query; AEB/8%l};v
3X,]=f@_
import com.adt.dao.UserDAO; vEu
Ka<5
xylpiSJ
/** [Bl
$IfU
* @author Joa E~'q?LJOB
*/ 1,m\Q_
public class UserDAOImpl extends BaseDAOHibernateImpl kJHr&=VO~
U*
-% M
implements UserDAO { `2Wl
>L#];|
/* (non-Javadoc) 3 %z
* @see com.adt.dao.UserDAO#getUserByName H|grbTv,
&mX5&e
(java.lang.String) `Af{H/qiI
*/ /p[|DJoM
publicList getUserByName(String name)throws b{Z^)u2X
T+`xr0
HibernateException { *!._Ais,\
String querySentence = "FROM user in class 6XQ*:N/4al
"9c.C I
com.adt.po.User WHERE user.name=:name"; D2Vb{ %(4.
Query query = getSession().createQuery Ask' !
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(querySentence); H+S~ bzz
query.setParameter("name", name); l[tY,Y:4qO
return query.list(); Dm7Y#)%8
} \;nD)<)J
6H(fk1E
/* (non-Javadoc) D+bB G
* @see com.adt.dao.UserDAO#getUserCount() Nr>c'TH
*/ 4JX`>a{<
publicint getUserCount()throws HibernateException { /X(@|tk:
int count = 0; 1"8Z
y6t
String querySentence = "SELECT count(*) FROM `4q5CJ2
43vGgGW
user in class com.adt.po.User"; \4[c}l
Query query = getSession().createQuery )B-MPuB
^VSt9&
(querySentence); yw;ghP;
count = ((Integer)query.iterate().next UN
cYu9[
xI=}z
()).intValue(); $sU5=,
return count; =gxgS<bde
} y#hga5
<C7M";54-
/* (non-Javadoc)
FY1},sq
* @see com.adt.dao.UserDAO#getUserByPage ioE66-n
+)/Rql(lY
(org.flyware.util.page.Page) 08TaFzP81
*/ [W^6u7~
publicList getUserByPage(Page page)throws o0,UXBx
C><<0VhU
HibernateException { *(?U
String querySentence = "FROM user in class W?*Xy6",JF
\_m\U.*
com.adt.po.User"; .V5q$5j
Query query = getSession().createQuery ib5;f0Qa
:FX'[7;p
(querySentence); +-Z"H)
query.setFirstResult(page.getBeginIndex()) OaD
Alrm
.setMaxResults(page.getEveryPage()); #6Efev
return query.list(); _n-VgPRn
} {-xi0D/Y;
,!o\),N
} {:};(oz)f
k| _$R?
'1>g=Ic0
=oL8d6nI
YtwmlIar`
至此,一个完整的分页程序完成。前台的只需要调用 \Dvl%:8
/0B07B
userManager.listUser(page)即可得到一个Page对象和结果集对象 no~O R Q
`^ieT#(O
的综合体,而传入的参数page对象则可以由前台传入,如果用 c,#~L7
J~_L4*Jw
webwork,甚至可以直接在配置文件中指定。 nUI63?
t*Z .e.q+
下面给出一个webwork调用示例: kPx]u\
java代码: @+0@BO12
baUEsg[~V
w0a+8gexi
/*Created on 2005-6-17*/ u+2xrzf
package com.adt.action.user; kjLsk-
H(5S Kv5
import java.util.List; }aHB$}"!
_~X8/p/Qh
import org.apache.commons.logging.Log; `^XRrVX<
import org.apache.commons.logging.LogFactory; x'E'jh%
import org.flyware.util.page.Page; [?|l X$<
lKh2LY=j
import com.adt.bo.Result; VTy,43<
import com.adt.service.UserService; _ 6+,R
import com.opensymphony.xwork.Action;
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F]K$u<U
/** \N#
HPrv}
* @author Joa ]t.WJC %
*/ zh#OD{
publicclass ListUser implementsAction{ ue6/EN;}
WL
IDw@fv
privatestaticfinal Log logger = LogFactory.getLog bm|Jb"T0b
Nt`F0
9S
(ListUser.class); Z/V`Z* fy
UA69_E{JCH
private UserService userService; LW83Y/7
_/QKWk&j
private Page page; *([0"
)V[w:= *
privateList users; h3UZ|B0=
Gx(K N57D
/* wf~5lpI[
* (non-Javadoc) :,h=2a_ 8
* {<-
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* @see com.opensymphony.xwork.Action#execute() Ak\D6eHcB
*/
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publicString execute()throwsException{ 7':5
Result result = userService.listUser(page); (]zl$*k
page = result.getPage(); k=h/i8i2z
users = result.getContent(); u):%5F/
return SUCCESS; mC{!8WC@k
} mFgb_Cd
),D`ZRXS
/** uZqu xu.
* @return Returns the page. qHC*$v#.V?
*/ SHXa{-
public Page getPage(){ 0,vj,ic*WX
return page; :|3"H&FWK
} C1#o<pv
t?%}hs\!
/** *'s2
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* @return Returns the users. ~
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*/ o5*74Mv
publicList getUsers(){ h|c:!VN@
return users; @mQ/WYs
}
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y0&V$uv/
/** T;:',T[G
* @param page cdek^/
* The page to set. uusY,Dt/9
*/ -tK;RQYax
publicvoid setPage(Page page){ y :i[~ y
this.page = page; Kd`l[56#
} +e\:C~2f28
Q?Bjq>
/** _Ssv:xc,
* @param users DMK"Q#Vw
* The users to set. Fu1|b2B-x
*/ XqE55Jclp
publicvoid setUsers(List users){ TeGLAt
this.users = users; 6bRQL}[
} iP#A-du
i)`zKbK
/** *mK);@pL
* @param userService *s<dgFA'
* The userService to set. Vne.HFXA
*/ \J3v>&m<7
publicvoid setUserService(UserService userService){ 8,H#t@+MT
this.userService = userService; % b>y
} X."h Tha5
} dp// p)B>
psyH?&T
GH; F3s
O'&X aaZV
fdCxMKlu;
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, p@N Er,GB
WrK^>
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 2\z`G
B!E<uVC
么只需要: 0o"<^]
_|
java代码: @WDqP/4
X/;"CM
AP?{N:+
<?xml version="1.0"?> F"@'(b
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ~qLhZR\g^
*Y^Y
1.0//EN" "http://www.opensymphony.com/xwork/xwork- zOu$H[
{C0OrO2:
1.0.dtd"> AVevYbucB
2fL88/'
<xwork> I8-&.RE
QLpTz"H
<package name="user" extends="webwork- *> &N
t
K_lCDiqG
interceptors"> 0R%uVJG
t-<[._:+
<!-- The default interceptor stack name S}xDB
(?&_6B.*
--> ! 4^L $
<default-interceptor-ref %BYlbEx
yS.fe[
name="myDefaultWebStack"/> lA^Kh
6 peM4X
<action name="listUser" woH3?zR
}Bod#|`
class="com.adt.action.user.ListUser"> $O]E$S${
<param ae(]9 VW
;u-< {2P
name="page.everyPage">10</param> kAQ\t?`x
<result Vp-OGX[
cwW~ *90#
name="success">/user/user_list.jsp</result> - m x3^
</action> n5,Pq+[
&<