Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 "\*)KH`C
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 4PVg?
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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 /K!)}f(6
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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 <l1/lm<#
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。 7Q/H+)
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分页支持类: \!-]$&,j4
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java代码: 2- L-=0
#:" ]-u^
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package com.javaeye.common.util; I0Do%
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import java.util.List; n`=S&oKH
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publicclass PaginationSupport { E{6ku=2F
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publicfinalstaticint PAGESIZE = 30; Mzg3i*
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privateint pageSize = PAGESIZE; :(enaHn#~
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privateList items; W4 q9pHQ
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privateint totalCount; 9y\nO)\Tv
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privateint[] indexes = newint[0];
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privateint startIndex = 0; `_vPElQXZ#
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public PaginationSupport(List items, int [%>*P~6nK
q"Bd-?9
totalCount){ 7eq.UyUxs
setPageSize(PAGESIZE); 3wN4kltt
setTotalCount(totalCount); CH+%q+I
setItems(items); hak#Iz0[C
setStartIndex(0); K/(LF}
} mV]~}7*Y;
>]}VD "\
public PaginationSupport(List items, int B#."cg4VR
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totalCount, int startIndex){ ' q9Ejig
setPageSize(PAGESIZE); ]Q^8
9?
setTotalCount(totalCount); ])pX)(a
setItems(items); R&s/s`pLW
setStartIndex(startIndex); Jur$O,u40l
} 0D:uM$
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public PaginationSupport(List items, int 3znhpHO)
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totalCount, int pageSize, int startIndex){ F-Z>WC{+
setPageSize(pageSize); Q9y|1Wg1W
setTotalCount(totalCount); *QW.#y>"j
setItems(items); dY?l
oFz
setStartIndex(startIndex); A f?&VD4K
} XF{2'x_R
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publicList getItems(){ N0fE*xo
return items; ed,+Slg
} ,,XHw;{
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publicvoid setItems(List items){ m";8 nm
this.items = items; ~l+~MB
} 0T3r#zQ
>&<D.lx
publicint getPageSize(){ ,_,7cor
return pageSize; z"5e3w
} \i~5H]?d
K~L"A]+
publicvoid setPageSize(int pageSize){ @TKQ_7BcB
this.pageSize = pageSize; -NG9?sI\U
} =L$RY2S"
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publicint getTotalCount(){ y^p%/p%
return totalCount; 17Q*
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} j@Us7Q)A(
nkk GJV!
publicvoid setTotalCount(int totalCount){ suj}A
if(totalCount > 0){ jaThS!>v
this.totalCount = totalCount; t[%=[pJHW
int count = totalCount / QL(}k)dB
/7*qa G
pageSize; [0+5 Gx
if(totalCount % pageSize > 0) h^9Ne/s~
count++; (K"t</]
indexes = newint[count]; d@|j>Z
for(int i = 0; i < count; i++){ '9wD+'c=A
indexes = pageSize * s|!b: Ms`
D/{ Spw@
i; _ )^n[_E
} \No22Je6d
}else{ a7NX~9g
this.totalCount = 0; K3UG6S\B
} Q!%CU8!`&
} 9aqFdlbY
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publicint[] getIndexes(){ cmh/a~vYaY
return indexes; #iGz&S3iN$
} P3XP=G`E
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publicvoid setIndexes(int[] indexes){ j1toV$)P
this.indexes = indexes; 1/qiE{NW
} [laX~(ND{
.yj=*N.
publicint getStartIndex(){ 48%a${Nvvj
return startIndex; Ah2XwFg?
} @p2dXJeR<
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publicvoid setStartIndex(int startIndex){ *DoEDw
if(totalCount <= 0) ~h[lu^ZSi
this.startIndex = 0; {_MU0=7c\
elseif(startIndex >= totalCount) ' *p-`
this.startIndex = indexes J>Rt2K
8CSvg{B
[indexes.length - 1]; !c`Q?aGV)
elseif(startIndex < 0) 0\}j[-`pF
this.startIndex = 0; PuABS>.;
else{ ~KfjT
p#
this.startIndex = indexes -+I! (?
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[startIndex / pageSize]; 7#|NQ=yd
} Xhkw<XbV
} &akMj@4;R
s9:2aLZ{
publicint getNextIndex(){ Y.*lO
int nextIndex = getStartIndex() + Q}Vho.N@=
!%M-w0vC9
pageSize; :U[_V4?7
if(nextIndex >= totalCount) E 0pF; P5
return getStartIndex(); C X'E+
else 0Rk'sEX,
return nextIndex; 01q7n`o#zf
} @%cJjZ5y
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publicint getPreviousIndex(){ {}^ELw
int previousIndex = getStartIndex() - LA@}{hU
x}>tX
pageSize; u!`C:C'
if(previousIndex < 0) ]R>k0X.V
return0; b~1p.J4
else IKr7"`
return previousIndex; !<6wrOMa O
} +m7x>ie)
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} $-AvH(@
>`\*{]
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抽象业务类 g4$%)0x%
java代码: 1W!n"3#
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mVL,J=2
/** < 5_Ys
* Created on 2005-7-12 9FLn7Y
*/ gX _BJ6
package com.javaeye.common.business; J+|ohA
q@-qA]
import java.io.Serializable; 7VXeu+-P
import java.util.List; imhq*f#A[
l?1!h2z%
import org.hibernate.Criteria; p+7BsW.l
import org.hibernate.HibernateException; !^fJAtCN]
import org.hibernate.Session; ;VFr5.*x
import org.hibernate.criterion.DetachedCriteria; lqCn5|S]
import org.hibernate.criterion.Projections; g^4FzJ
import =U2Te
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org.springframework.orm.hibernate3.HibernateCallback; 9iy|=
import @
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org.springframework.orm.hibernate3.support.HibernateDaoS 9cmJD5OO
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upport; -9*WQU9R
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import com.javaeye.common.util.PaginationSupport; @ty|HXW
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public abstract class AbstractManager extends >C}RZdO~
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HibernateDaoSupport { _Usg`ax-
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privateboolean cacheQueries = false; `j<tI6[e
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privateString queryCacheRegion; f,a %@WT
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publicvoid setCacheQueries(boolean y&Hh8|'mC
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cacheQueries){ 19u?^w
this.cacheQueries = cacheQueries; Aii[=x8
} .KsvRx
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publicvoid setQueryCacheRegion(String Fb'wC
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queryCacheRegion){ dR+$7N$
this.queryCacheRegion = kZ9pgdI
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queryCacheRegion; pzr-}>xrZ
} !~l%6Z5
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publicvoid save(finalObject entity){ cj#q7
getHibernateTemplate().save(entity); %$xFnGb
} 6 {Z\cwP)c
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publicvoid persist(finalObject entity){ yMkd|1
getHibernateTemplate().save(entity); `7_LJ
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} ~&:R\
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publicvoid update(finalObject entity){ vrv*k
getHibernateTemplate().update(entity); swFOh5z
} ~`E4E
@ 1A_eF
publicvoid delete(finalObject entity){ #+PbcL
getHibernateTemplate().delete(entity); o{LFXNcg[
} `C?OAR44
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publicObject load(finalClass entity, g:M7/- "
b]#d04]
finalSerializable id){ !S-U8KI|
return getHibernateTemplate().load [ d7]&i}*|
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(entity, id); <;e#"(7
} XE*bRTEw
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publicObject get(finalClass entity, se HbwO3 b
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finalSerializable id){ gu[dw3L
return getHibernateTemplate().get hY 2PV7"[;
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(entity, id); RAI&;"
} :Qo
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publicList findAll(finalClass entity){ 34Khg
return getHibernateTemplate().find("from +yH~G9u(
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" + entity.getName()); vqi$}=%n?W
} X2YOD2<v
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publicList findByNamedQuery(finalString <,4(3 >js
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namedQuery){ /$,=>
return getHibernateTemplate Z<<gz[$+p
f {Z%:H
().findByNamedQuery(namedQuery); by[i"!RCu
} i%4k5[f.:
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publicList findByNamedQuery(finalString query, HbfB[%
a
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finalObject parameter){ S{T d/1}
return getHibernateTemplate jY+S,lD
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().findByNamedQuery(query, parameter); ,D2_Z]
} gCr|e}w-
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publicList findByNamedQuery(finalString query, lY*]&8/=
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finalObject[] parameters){ /.YAFH|i)"
return getHibernateTemplate oImgj4C2L
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().findByNamedQuery(query, parameters); ?lN8~Ze
} M2Fj)w2
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publicList find(finalString query){ wKS-O%?
return getHibernateTemplate().find gam#6
s
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(query); EvQwGt1)P
} ZNpExfGEU
{V%O4/
publicList find(finalString query, finalObject ,nB3c5X)|
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parameter){ 8{SU?MHQLE
return getHibernateTemplate().find G? gXK W
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(query, parameter); 355Sd;*
} D>b5Uwt
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public PaginationSupport findPageByCriteria ]Bd3d%
|EV\a[
(final DetachedCriteria detachedCriteria){ !FO^:V<|5
return findPageByCriteria #lsh N,CPm
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); pNE\@U|4E
} @PoFxv
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public PaginationSupport findPageByCriteria K}E7|gdG
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(final DetachedCriteria detachedCriteria, finalint Oqpl2Y"/
-jtC>_/
startIndex){ 14n="-9
return findPageByCriteria -N8cjr4l
dEd ]U49u
(detachedCriteria, PaginationSupport.PAGESIZE, B5,QJ W*
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startIndex); koEX4q
} UcLNMn|
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public PaginationSupport findPageByCriteria ]ZKt1@4AY
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(final DetachedCriteria detachedCriteria, finalint g2{H^YUN$_
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pageSize, p=_XMh`;
finalint startIndex){ Vx6?@R
return(PaginationSupport) fHe0W
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getHibernateTemplate().execute(new HibernateCallback(){ Uy59zB2|=
publicObject doInHibernate e4=FU&RpNH
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(Session session)throws HibernateException { {#1j"
Criteria criteria = 2'<=H76
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detachedCriteria.getExecutableCriteria(session); Awa|rIM
int totalCount = |v$%V#Bo
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((Integer) criteria.setProjection(Projections.rowCount -M:hlwha
q]N?@l]
()).uniqueResult()).intValue(); }>;ht5/i/
criteria.setProjection ewAH'H]o
~S^X"8(U
(null); HLSfoQ&)v
List items = juCG?}di;
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criteria.setFirstResult(startIndex).setMaxResults 9jMC|oE
H\=LE
(pageSize).list(); i'Y'HI
PaginationSupport ps = 6i]Nr@1C
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new PaginationSupport(items, totalCount, pageSize, oT|P1t.
j(%gMVu
startIndex); 'z-;* !A}j
return ps; L`jB)wF/J
} aI={,\
}, true); $K?T=a;z
} )pjjW"C+
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public List findAllByCriteria(final WXLe,7y
&R'w-0k_
DetachedCriteria detachedCriteria){ ,l$NJt
return(List) getHibernateTemplate N4a`8dS|
Z#4JA/c!
().execute(new HibernateCallback(){
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publicObject doInHibernate % QPWw~}:
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(Session session)throws HibernateException { h"u<E\g
Criteria criteria = 'T )Or,d
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detachedCriteria.getExecutableCriteria(session); 2#AeN6\@
return criteria.list(); 7`blGzP_
} }iua]
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}, true); 9u?)vR[@e
} }z%OnP
selP=Q!
public int getCountByCriteria(final rb:<N%*t
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DetachedCriteria detachedCriteria){ |jahpji6
Integer count = (Integer) !Tn0M;
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getHibernateTemplate().execute(new HibernateCallback(){ <I7(eh6d
publicObject doInHibernate ~LawF_]6
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(Session session)throws HibernateException { p-5Pas
Criteria criteria = 9W1;Kb|Z<
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detachedCriteria.getExecutableCriteria(session); y$IaXr5L
return (O8,zqP9l
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criteria.setProjection(Projections.rowCount y#S1c)vU
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()).uniqueResult(); 4 ,p#:!
} eM?rc55|
}, true); !uWxRpT,7
return count.intValue(); cVQatm
} xi680'
} ^Sy^+=wK3
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用户在web层构造查询条件detachedCriteria,和可选的 O6yP
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 {]&R8?%
JAc@S20v\
PaginationSupport的实例ps。 .Qd}.EG
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ps.getItems()得到已分页好的结果集 9;=q=O/
ps.getIndexes()得到分页索引的数组 Ur^YG4(
ps.getTotalCount()得到总结果数 C/F@ ]_y
ps.getStartIndex()当前分页索引 L)q`D2|'
ps.getNextIndex()下一页索引 Uh|TDuM
ps.getPreviousIndex()上一页索引 ]{YN{
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$ "Afy)Ir
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"
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}dy9IH
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 A?e,U,
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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 lZ}P{d'f.
F(deu^s%{
一下代码重构了。 uu}'i\Q
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我把原本我的做法也提供出来供大家讨论吧: 49o\^<4b
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首先,为了实现分页查询,我封装了一个Page类: S#,+Z7
java代码: F
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/*Created on 2005-4-14*/ PmHd9^C
package org.flyware.util.page; ]de\i=?|
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/** /K f L+"^|
* @author Joa iBucT"d]
* Tj=gRQ2v
*/ UL&} s_
publicclass Page { -(!uC+BZX
Kk 7GZ
/** imply if the page has previous page */
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privateboolean hasPrePage; \fTTkpM
fTBVvY4(
/** imply if the page has next page */ k!&:(]
privateboolean hasNextPage; mxgqS=`
jDkm:X}:
/** the number of every page */ {t&*>ma6)
privateint everyPage; d [r-k 2
J<rlz5':
/** the total page number */ :i.t)ES
privateint totalPage;
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/** the number of current page */ }"hW b(
privateint currentPage; ]
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>
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/** the begin index of the records by the current M;qBDT~)
I`NUurQTX
query */ ?z3]
privateint beginIndex; !:3^ hb
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/** The default constructor */ 8&%Cy'TIz4
public Page(){ JRXRi*@
Apmw6cc
} SyAo,
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e gI&epN
/** construct the page by everyPage e9 *lixh
* @param everyPage E:)Cp
* */ LX\)8~dp
public Page(int everyPage){ ;,k=<]
this.everyPage = everyPage; !.*iw
k`
} L!,d"wuD
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/** The whole constructor */ `^x9(i/NE
public Page(boolean hasPrePage, boolean hasNextPage, H'Nq#K
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tF^g<)S;t
int everyPage, int totalPage, 4@h;5
int currentPage, int beginIndex){ Kk=LXmL2
this.hasPrePage = hasPrePage; Yk'm?p#~
this.hasNextPage = hasNextPage; ywOmQcZ
this.everyPage = everyPage; QjJfE<h
this.totalPage = totalPage; Z5$fE7ba+
this.currentPage = currentPage; l[oe*aYN7
this.beginIndex = beginIndex; Lc|{aN
} P6.!3%y
T cJ$[
/** &qKigkLd
* @return RU|X*3";T
* Returns the beginIndex. i'=2Y9S}
*/ ,5{$+
publicint getBeginIndex(){ 'C^;OjAg
return beginIndex; p?JQ[K7i
} Z/g]o#
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/** *C7F2o
* @param beginIndex R5(F)abi
* The beginIndex to set. LTXz$Z]
*/ dxCPV6 XI
publicvoid setBeginIndex(int beginIndex){ H O*YBL
this.beginIndex = beginIndex; [9AM\n>g
} F?BS717qS%
<( EyXV
/** wt?o
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* @return pawl|Z'Ez
* Returns the currentPage. aClA{
*/ g*J@[y;
publicint getCurrentPage(){ ~x#vZ=]8
return currentPage; N}x9N.
} Xb,T{.3@
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/** N 9LgU)-Jt
* @param currentPage u okc:D
* The currentPage to set. 4x=(Zw_X
*/ ~KPv7WfG
publicvoid setCurrentPage(int currentPage){ 4-^[%&>}
this.currentPage = currentPage; 0[Eb .2I
} ykmv'a$-4
v@n_F
/** E
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* @return Z9[+'ZWt
* Returns the everyPage. ||Y<f *
*/ ~=cmM
publicint getEveryPage(){ S&wzB)#'
return everyPage; u-:Ic.ZV
} 'SV7$,mK@
"r$/
/** )];aI A$
* @param everyPage tJ'iX>9I
* The everyPage to set. v0LGdX)/Y
*/ pr rT:Y
publicvoid setEveryPage(int everyPage){ nB] Ia?
this.everyPage = everyPage; s`;f2B/|
} +~35G:&:
jatr/
/** 5k$vlC#[H
* @return WU)Ss`s \
* Returns the hasNextPage. suVmg-d
*/ FFvCi@oT
publicboolean getHasNextPage(){ NBOCt)C;H
return hasNextPage; r4Q|5kT*i
} zK;XFN#U^
g7n"
/** ?fK1
* @param hasNextPage E!mmLVa9
* The hasNextPage to set. \Y5W!.(%w
*/ q-_' W,
publicvoid setHasNextPage(boolean hasNextPage){ Z
a(|(M H
this.hasNextPage = hasNextPage; 3CZS)
} 6gU{(H
"#4dW 7E
/** @D[`Oj)
* @return L0"~[zB]N
* Returns the hasPrePage. ZA820A>2!
*/ |5MbAqjzC
publicboolean getHasPrePage(){ `^6 ,kI-c
return hasPrePage; ~ap2m
} 6q/?-Qcy
:dwt1>
/** e.vtEQV9
* @param hasPrePage J2M(1g)t9
* The hasPrePage to set. r:g9 Z_
*/ Ed-M7#wY
publicvoid setHasPrePage(boolean hasPrePage){ tSHFm-q`
this.hasPrePage = hasPrePage; 0xMj=3']
} 3)N\'xFh@
i$uN4tVKT
/** .%}+R|g
* @return Returns the totalPage. DL8x":;
* @S3f:s0~D
*/ Yj3I5RG
publicint getTotalPage(){ XKU=oI0\j
return totalPage; <<zI\+V
} )^x K
vhgLcrn
/** {C3Y7<
* @param totalPage 7~UR!T9
* The totalPage to set. 'i|rjW(
*/ eV};9VJ$F
publicvoid setTotalPage(int totalPage){ .*5 Z"Q['G
this.totalPage = totalPage; >)**khuP7
} ELD!{bMT
JAjku6
} \ |!\V
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*hY2.t; X
L%\b' fs
2A:,;~UH
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 wCKj7y[
{/8Q)2*>0
个PageUtil,负责对Page对象进行构造: {eT.SO
java代码: I 3$dVls}
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/*Created on 2005-4-14*/ !8Rw O%c(
package org.flyware.util.page; tWPO]3hW
{D`T0qPT[
import org.apache.commons.logging.Log; B80aw>M
import org.apache.commons.logging.LogFactory; e%O0hE
k$i'v:c|:i
/** =o 7}]k7
* @author Joa 4P8*k[.
* Jjm|9|C,
*/ K[?Xm"4
publicclass PageUtil { n1v5Q2xw
g@ith&*=h
privatestaticfinal Log logger = LogFactory.getLog 9pSUIl9|j
Ud(`V:d
(PageUtil.class); }}{Yw
H=^K@Ti:
/** <V&5P3)d9
* Use the origin page to create a new page 'MxSd( T
=
* @param page F"jt&9jg
* @param totalRecords gAbD7SE
* @return A%bCMP
*/ vqdX^m^PY
publicstatic Page createPage(Page page, int I PCGt{B~
\XzM^K3
totalRecords){ _^ |2}t
return createPage(page.getEveryPage(), [k%4eO2p "
4=<*Vd`p
page.getCurrentPage(), totalRecords); [.,>wo~
}
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/** zGo|JF
* the basic page utils not including exception K\?]$dK5
DBH#)4do@
handler {dWObh
* @param everyPage r6.d s^
* @param currentPage ~/#1G.H
* @param totalRecords mTDVlw0dh
* @return page e@<?zS6
*/ /n,a?Ft^N)
publicstatic Page createPage(int everyPage, int %&<LNEiUN
(P|pRVO
currentPage, int totalRecords){ !nf-}ze{
everyPage = getEveryPage(everyPage); t+ Bf#:
currentPage = getCurrentPage(currentPage); 8?FueAM'
int beginIndex = getBeginIndex(everyPage, GZ #aj|
]$iqa"{
currentPage); 3lxc4@Zmd
int totalPage = getTotalPage(everyPage, KLWDo%%u
(R}ii}&
totalRecords); 5TKJWO.
boolean hasNextPage = hasNextPage(currentPage, _GYMPq\%L#
2 -+f1,
totalPage); aAt>QxGQW
boolean hasPrePage = hasPrePage(currentPage); qL
/7^)(
z? ]G3$i(
returnnew Page(hasPrePage, hasNextPage, -0uV z)
everyPage, totalPage, 2@j";+
currentPage, X@A1#z+s0]
%eWqQ3{P]
beginIndex); }Fb!?['G5
} 4"?^UBr
SX0_v_%M
privatestaticint getEveryPage(int everyPage){ Q /x8 #X
return everyPage == 0 ? 10 : everyPage; ~aK?cP
} qt e>r
'fd1Pj9~$
privatestaticint getCurrentPage(int currentPage){ ib6^x:HGU
return currentPage == 0 ? 1 : currentPage; AONDx3[
} 2'0K WYM
uKr1Z2
privatestaticint getBeginIndex(int everyPage, int SI:ifR&T
2 ][DZl
currentPage){ r#i?j}F}
return(currentPage - 1) * everyPage; \_6OC Vil
} ,El!fgL
2\D8.nQr
privatestaticint getTotalPage(int everyPage, int ;t#]2<d*
LJlZ^kh
totalRecords){ aBuoHdg;
int totalPage = 0; V&{MQWy
S_(d9GK<
if(totalRecords % everyPage == 0) #o`Ny4sq/
totalPage = totalRecords / everyPage; `|Z}2vo;j
else kma?v B
totalPage = totalRecords / everyPage + 1 ; coE&24,0
.x83Ah`
return totalPage; Pt,ebL~
} CB\{!
z`@^5_
privatestaticboolean hasPrePage(int currentPage){ 7E$&2U^Js
return currentPage == 1 ? false : true; iP@6hG`:
} iPG0o
%
{}~: &.D
privatestaticboolean hasNextPage(int currentPage, YvL?j
Y$>-%KcKeI
int totalPage){ bzpFbfb
return currentPage == totalPage || totalPage == m!n/U-^
W~n.Xeu{C
0 ? false : true; >`RRP}u=u
} Ut@RGg+f8
>H][.@LyR
\*T"M*;
} OR6ML-|
jyS=!ydn+
fK}h"iH+K
-Yi,_#3{
)Q;978:
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。 M)-6T{[IT
\ gwXH
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 Njc%_&r
dhPKHrS
做法如下: XUMX*
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 w&h2y4
&7mW9]
的信息,和一个结果集List: .1 )RW5|c
java代码: I5ss0JSl/
={2!c0s
nwI3| &
/*Created on 2005-6-13*/ gO?44^hMe
package com.adt.bo; @LE[ac
f7urJ'!V
import java.util.List; X?r48l??
bp<^R
import org.flyware.util.page.Page; l(W[_ D
4Aes#{R3v
/** ,Dmc2D
* @author Joa ]:]H:U]p
*/ +]xFoH
publicclass Result { %hS|68pN6
e'*HS7g
private Page page; Y
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jjs&`Fy,
private List content; G`h+l<
'vV$]/wBF
/** jF ^5}5U
* The default constructor od<b!4k~s
*/ #^#Kcg
public Result(){ [onqNp
super(); BbOu/i|
} 0X|_^"!
GV|9H]_,I
/** shC;hR&;
* The constructor using fields :t$aN|>y
* ihe(F7\U
* @param page 9v)%dO.
* @param content qNgd33u1
*/ is;XmF*5=
public Result(Page page, List content){ O>y'Nqz
this.page = page; MhEw
_{?
this.content = content; !eR3@%4
} S0/usC[r
$P
o}
/** $o?@0
* @return Returns the content. -cF'2Sfr
*/ ~,6b_W p/
publicList getContent(){ 5AeQQU
return content; sd re#@n}
} \t4tiCw
Z,7R;,qX
/** imL_lw^?
* @return Returns the page. b;mSQ4+
*/ \uOdALZ
public Page getPage(){ h[tix:
return page; -<_$m6x"A
} U]~^Z R
:&XH?/Wi
/** u`:hMFTID
* @param content Gi6T["
* The content to set. Xk mQBV"
*/ H jNxqaljt
public void setContent(List content){ Btt]R
this.content = content; Yepe=s+9
} .0HZNWRtb
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/** Y$8JM
* @param page t%1 ^Li
* The page to set. O;Y:uHf
*/ t=euE{c
publicvoid setPage(Page page){ Kr`]_m
this.page = page; +V862R4,o
} q~K(]Ya/
} @JkK99\(>9
qF)<H
7Du1RuxP
nxm$}!Df
,.IEDF<&
2. 编写业务逻辑接口,并实现它(UserManager, (WlIwKP
.S\&L-{
UserManagerImpl)
xFv;1Q
java代码: JOnyrks
4JIYbb-a'
lG<hlYckv
/*Created on 2005-7-15*/ I,6/21kO
package com.adt.service; p4u5mM
"I-
w
import net.sf.hibernate.HibernateException; #!J(4tXny
^cvl:HOog
import org.flyware.util.page.Page; Br>Fpe$q4
u~zs*
qp
import com.adt.bo.Result; lb'Cl 3H
`'_m\uo
/** ~vdkFc(8B
* @author Joa W{cY6@
*/ `Kl`VP=c
publicinterface UserManager { &:*q_$]Oz
9~IQw#<
public Result listUser(Page page)throws 0"k|H&
[p r"ZQ]
HibernateException; Y]`.InG@
6qvp*35Cx
} E9!N>0
s=I'e/"7
\g)Xt?w0Wo
RH;:9_*F
g\oSG)
java代码: 3#kitmV
g\A
y`.s
YMpf+kN
/*Created on 2005-7-15*/ \6|/RFT
package com.adt.service.impl; ,FQdtNMap
0IM8
import java.util.List; "R
#k~R
woH)0v
import net.sf.hibernate.HibernateException; =/Aj
%T`U^Pnr
import org.flyware.util.page.Page; %5Kq^]q;Y
import org.flyware.util.page.PageUtil; >"X\>M`"
s'P( ,!f
import com.adt.bo.Result; X+8B!F
import com.adt.dao.UserDAO; +~Cy$MCX
import com.adt.exception.ObjectNotFoundException; Jwn AW}=
import com.adt.service.UserManager; f6<g3Q7Mu
`xS{0P{uj
/** t-%Q`V=[
* @author Joa [V#r7a
*/ ^S)TO}e
publicclass UserManagerImpl implements UserManager { [(LV
p 5u_1U0
private UserDAO userDAO; BF|(!8S$U
m8]?hJY3l
/** {-zMHVw=}
* @param userDAO The userDAO to set. :Gqy>)CxX
*/ Tn-C>=tR~%
publicvoid setUserDAO(UserDAO userDAO){ DdV'c@rq+
this.userDAO = userDAO; V%
TH7@y
} %n0;[sD0A
UnWW/]E
/* (non-Javadoc) a.F Al@Br
* @see com.adt.service.UserManager#listUser )8gGv
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(org.flyware.util.page.Page) :q3+AtF
*/ 4NVV5_K a
public Result listUser(Page page)throws dmrps+L
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HibernateException, ObjectNotFoundException { 9e!NOl\_;.
int totalRecords = userDAO.getUserCount(); 5@osnf?
if(totalRecords == 0) {WN(&eax
throw new ObjectNotFoundException [ANuBNF
46jh-4)<
("userNotExist"); RH)EB<PV
page = PageUtil.createPage(page, totalRecords); s3s4OAY
List users = userDAO.getUserByPage(page); hi=XYC,
returnnew Result(page, users); ;_kzcK!l
} &UHPX?x
_=6 rE
} +WJ(QZEhD
H Yr}wG
UO`;&e-DB
AtS;IRN@
e`tLR- &
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 _K9VMczj
qL5I#?OMkU
询,接下来编写UserDAO的代码: b}ODWdJ1
3. UserDAO 和 UserDAOImpl: Lju7,/UD
java代码: UQCo}vM
k?nQ?B
W
w-B^
[<
/*Created on 2005-7-15*/ R
package com.adt.dao; u?ek|%Ok
I&c ~8Dw
import java.util.List; )-rW&"{U
H14Ic.&
import org.flyware.util.page.Page; YO)$M-]>%J
AT
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H
import net.sf.hibernate.HibernateException; AZ |yX
,"-Rf<q/
/** G%p~m%zIK
* @author Joa &>WWzikB*
*/ "e3["'
publicinterface UserDAO extends BaseDAO { "tit\a6\(
\h<BDk*
publicList getUserByName(String name)throws 89}Y5#W
gE/Tj$
HibernateException; Fh7'[>onw
0Y=![tO8
publicint getUserCount()throws HibernateException; 1B>V t*=
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publicList getUserByPage(Page page)throws _&3<6$}i"
|iFVh$N
HibernateException; ~`;rNnOT3
Q\
^[!|
} UCrh/b Tm
3CjL\pIC
FUK3)lT
WnFG{S{s
NIr@R7MKd
java代码: gCd`pi
8
bSwWszd~
({0)@+V8
/*Created on 2005-7-15*/ OIHz I2{
package com.adt.dao.impl; ?{"mP 'dD
:yT-9Ze%q
import java.util.List; $5`!Z%>/
+Z2MIC|Ud
import org.flyware.util.page.Page; /(I*,.d
~\nBjM2
import net.sf.hibernate.HibernateException; ;32#t[ib
import net.sf.hibernate.Query; Ax3W2s
)Ag/Qep
import com.adt.dao.UserDAO; !;@_VWR
38V3o`f
/** 7DW]JK l
* @author Joa lor8@Qz
*/ 3LR p2(A
public class UserDAOImpl extends BaseDAOHibernateImpl ;Lw{XqT
M_0zC1
implements UserDAO { 1xNVdI
:R6bq!
/* (non-Javadoc) ^_I} x)i*@
* @see com.adt.dao.UserDAO#getUserByName M/D)".;
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(/U3}w-
(java.lang.String) kpwt]]e*
*/ hli|B+:m"
publicList getUserByName(String name)throws Oh.ZPG=
*x~xWg9^
HibernateException { 1RLY $M
String querySentence = "FROM user in class WlB'YL-`g
;P &y,:<m:
com.adt.po.User WHERE user.name=:name"; 6TWWlU^e
Query query = getSession().createQuery 5/[H+O1;
u/b7Z`yX}
(querySentence); kID[#g'
query.setParameter("name", name); Q0?\]2eet9
return query.list(); gIWrlIV{9
} mAgF73,3
J`M&{UP
/* (non-Javadoc) |XYEn7^r
* @see com.adt.dao.UserDAO#getUserCount() eC
DIwB28
*/ 8GPIZh'0h
publicint getUserCount()throws HibernateException { c;f!!3&
int count = 0; Z!d7&T}
String querySentence = "SELECT count(*) FROM =+5,B\~q@C
,?UM;^
user in class com.adt.po.User"; 75!9FqMZ}
Query query = getSession().createQuery -${DW^txMZ
+@9gkPQQ-@
(querySentence); {P9J8@D
count = ((Integer)query.iterate().next e/_C
w"m+~).U
()).intValue(); 14eW4~Mr
return count; os3 8u!3-
} CD j~;$[B
C#rc@r,F
/* (non-Javadoc) JE5
* @see com.adt.dao.UserDAO#getUserByPage ;^
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{n3EGSP#
(org.flyware.util.page.Page) uy _wp^
*/ cxeghy:;U
publicList getUserByPage(Page page)throws 3:/'t{ ^B
xVB;s.'!
HibernateException { {3a&1'a0g
String querySentence = "FROM user in class XKL3RMF9r
3gWvmep1
com.adt.po.User"; aIy*pmpD=
Query query = getSession().createQuery kB:Uu}(=N
1[F3 Z
(querySentence); sRVIH A,
query.setFirstResult(page.getBeginIndex()) C-eA8pYY/
.setMaxResults(page.getEveryPage()); -Ue$T{;RoH
return query.list(); \mM<\-'p
} |rw%FM{F
N(6|yZ<J3M
} mM.*b@d-
>DM44
V~DMtB7
Xm2\0=v5;
8VG!TpX/B
至此,一个完整的分页程序完成。前台的只需要调用 -W{DxN1
&K_)#v`|
userManager.listUser(page)即可得到一个Page对象和结果集对象 Tl]e%A`|
$yDWu"R8
的综合体,而传入的参数page对象则可以由前台传入,如果用 vgt]:$
m ~#!
webwork,甚至可以直接在配置文件中指定。 NvE}eA#
UEs7''6RM
下面给出一个webwork调用示例: %t=kdc0=_
java代码: +i ?S
+=Jir1SLV
,&PE6hn
/*Created on 2005-6-17*/ VLsxdwHgb
package com.adt.action.user; C,V%B
1sE?YJP-
import java.util.List; 8*SDiZ
_8fr6tO+
import org.apache.commons.logging.Log; [%~
:@m
import org.apache.commons.logging.LogFactory; c5q9LQ/
import org.flyware.util.page.Page; "]'?a$\ky:
yw[ #
import com.adt.bo.Result; +cJy._pi!
import com.adt.service.UserService; :a8 YV!X
import com.opensymphony.xwork.Action;
OV2-8ERS
t-
u VZ!`\
/** (2ur5uk+
* @author Joa H~eRT1
*/ !IU.a90V
publicclass ListUser implementsAction{ o56`
cUqn<Z<n
privatestaticfinal Log logger = LogFactory.getLog I4;A8I
3K&4i'}V
(ListUser.class); 84HUBud76Y
c0c|z
Ym
private UserService userService; m42T9wSsx
^2d!*W|
private Page page; AT2v!mNyCw
%:>3n8n
privateList users; Sw^X2$h
65z"
/* ^
&E}r{?
* (non-Javadoc) AIb2k
* 1XG!$4DW
* @see com.opensymphony.xwork.Action#execute() ^
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*/ ~vLW.:
publicString execute()throwsException{ gM>t0)mGK
Result result = userService.listUser(page); L!/\8-&$P
page = result.getPage(); 4${jr\q]
users = result.getContent(); ~DO4,
return SUCCESS; tMj;s^P1
} s,bERN7'yO
T +5X0 Nv
/** `k(yZtb
* @return Returns the page. s &Dg8$
*/ W{z.?$SH
public Page getPage(){ A,i75kd
return page; iu**`WjI\
} qQ\Y/}F
`&0Wv0D0
/** x@mL $
* @return Returns the users. =_j vk.
*/ FYs)MO
publicList getUsers(){ umz;F
return users; xw{-9k-~
} A5,t+8`aci
*5tO0_L
/** \txbhWN
* @param page jq'!UN{
* The page to set. HW&%T7
a
*/ &DqE{bBd!
publicvoid setPage(Page page){ dd2[yKC`
this.page = page; Y|8vO
} \xg]oKbn
Y`+=p@2O2o
/** ,mRyQS'F
* @param users Bq/:Nd[y
* The users to set. 7+./zN
*/ Vcd.mE(t%
publicvoid setUsers(List users){ $/Aj1j`"9+
this.users = users; L@=3dp!\Cu
} sNun+xsf^
'B+ ' (f
/** &d7Z6P'`G
* @param userService A^Kbsc
* The userService to set. +cb6??H
*/ .q+0pj
publicvoid setUserService(UserService userService){ zByT$P-
this.userService = userService; ceNix!P
} B^).BQ
} aq7~QX_0G
"3FihE]k
5s(1[(
5SCKP<rb
04r$>#E
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, L(GjZAP
j*xV!DqC
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 `y#UJYXQE
3D?sL!W
么只需要: %s19KGpA
java代码: z;@*r}H
9Fn\FYUq
!8`3GX:B_
<?xml version="1.0"?> SkU9ON
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 0M\D[mg
j,]Y$B
1.0//EN" "http://www.opensymphony.com/xwork/xwork- RK w$- 7O
mf'V)
1.0.dtd"> NnVnUgx
(sWLhUgRX
<xwork> G[jW<'f
iQ{G(^sZN
<package name="user" extends="webwork-
Ov<NsNX]
OR[{PU=X
interceptors"> !!Z?[rj
dz Zb
<!-- The default interceptor stack name `~eUee3b.~
QeF3qXI
--> FVhU^
<default-interceptor-ref .F+@B\A<
DBP9{ x$
name="myDefaultWebStack"/> 8QMPY[{
!ct4;.2
D
<action name="listUser" I-OJVZ( V
a22XDes=
class="com.adt.action.user.ListUser"> uslQ*7S[^
<param +}jJ&Z9)
XrZ*1V
name="page.everyPage">10</param> V)}rEX
<result v%Wx4v@%SE
,AT[@
name="success">/user/user_list.jsp</result> (p%>j0<
</action> A_KW(;50
>M&3Y
XC
</package> ](|\whI
ID/F
</xwork> HV<Lf
6gE
1'?4m0W1
R:B^
qe5feky
J=/5}u_gw
*2jK#9"MP
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 r&FDEBh
6-O_\Cq8
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 bJs9X/E
@B}aN@!/
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 4[N^>qt =
y!xE<S&Y
W^"AU;^V56
JchSMc.9
0wS+++n$5
我写的一个用于分页的类,用了泛型了,hoho Y".RPiTL
* RtgC/
java代码: *?MGMhE
fDLG>rXPT
R
LD`O9#j
package com.intokr.util; Z(Jt~a3o
n?V+dC=F}
import java.util.List; -lv)tHs<
K$d$m <
/** hJPlq0C
* 用于分页的类<br> QE7V.
>J_p
* 可以用于传递查询的结果也可以用于传送查询的参数<br> c*~]zR>s!
* 13Lr}M&
* @version 0.01 %iw3oh&Fkm
* @author cheng 9?k_y ZV
*/ uG<}N=
public class Paginator<E> { {p,]oOq\
privateint count = 0; // 总记录数 NF?
vg/{
privateint p = 1; // 页编号 CD8}I85K
privateint num = 20; // 每页的记录数 mx=BD'
privateList<E> results = null; // 结果 vhhC>
7
h yv2SxP*
/** 2PG [7u^
* 结果总数 "Iix
)Ue
*/ g&{9VK6.
publicint getCount(){ =z8f]/k*>
return count; i7ly[6{^pr
} VH:]@x//{
Od|$Y+@6
publicvoid setCount(int count){ #^]n0!
this.count = count; mml
z&h
} x,'!eCKN
z<5m
fAm
/** V(E/'DR
* 本结果所在的页码,从1开始 ccL~#c0P7
* 3'X.}>o
* @return Returns the pageNo. (P`3 @H
*/ +U@<\kIF
publicint getP(){ ZzX~&95G
return p; n?c]M
} &