Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 9N^&~O|1
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 mgeNH~%m@*
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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 Jt6~L5[_s
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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 ;5tSXgGw7
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。 AtNu:U$
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分页支持类: b?U!<s.
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java代码: LO8V*H(
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package com.javaeye.common.util; hamn9
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import java.util.List; BR5r K
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publicclass PaginationSupport { :4|W;Lkd!
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publicfinalstaticint PAGESIZE = 30; d)m+Hc.
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privateint pageSize = PAGESIZE; 4}B9y3W:v
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privateList items; (JS1}T
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privateint totalCount; mx s=<
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privateint[] indexes = newint[0]; )+2GF0%
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privateint startIndex = 0; j["b*X`8G
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public PaginationSupport(List items, int )24r^21.q
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totalCount){ O:'UsI1Y
setPageSize(PAGESIZE); j`1%a]Bwc
setTotalCount(totalCount); L{xCsJ3d
setItems(items); }9[E+8L1
setStartIndex(0); \4y7!
} [ h7nOUL!
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public PaginationSupport(List items, int X
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totalCount, int startIndex){ <^+~?KDZM
setPageSize(PAGESIZE); H)S&sx#q]
setTotalCount(totalCount); j!9p#JK#u
setItems(items); ia!t~~f
setStartIndex(startIndex); ]c,ttS_
} Afi;s.,
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public PaginationSupport(List items, int E! ;giPq*n
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totalCount, int pageSize, int startIndex){ D}59fWz@
setPageSize(pageSize); xwG=&+66
setTotalCount(totalCount); uxF88$=!t
setItems(items); /I|.^ Id|
setStartIndex(startIndex); s-]k 7a2V
} _y{z%-
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publicList getItems(){ 7!Z\B-_,
return items; -MZLkS U
} ! 9B| `
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publicvoid setItems(List items){ ehQ"<.sQ
this.items = items; /*J}7
} ;pu68N(B
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publicint getPageSize(){ "HTp1
return pageSize; -.=q6N4
} "2HSb5b"`
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publicvoid setPageSize(int pageSize){
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this.pageSize = pageSize; NBzyP)2)
} G+?@4?`z
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publicint getTotalCount(){ Htn'(Q
return totalCount; BU-+L}-48
} ZzET8?8
EMME?OW$
publicvoid setTotalCount(int totalCount){ ^LgaMmz
if(totalCount > 0){ X6s6fu;
this.totalCount = totalCount; a-\\A[E
int count = totalCount / qa
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pageSize; N=hr%{}c
if(totalCount % pageSize > 0) 4/;
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count++; vq yR aaMf
indexes = newint[count]; Rh#0EbE2
for(int i = 0; i < count; i++){ ~qe9U 0
indexes = pageSize * wWs<{ T
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i; Erz{{kf]1V
} {B$cd?}
}else{ gAt[kW< n
this.totalCount = 0; /MHqt=jP6
} csZIBi
} j.O7-t%C
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publicint[] getIndexes(){ $P#Cf&R
return indexes; Wlm%W>%
} k{>rI2;
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publicvoid setIndexes(int[] indexes){ v#u]cmI
this.indexes = indexes; vaQZ1a,
} H'68K8i0
p] kpDx[9
publicint getStartIndex(){ x
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return startIndex; 1;E[Ml
} MK"PCE5^i6
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publicvoid setStartIndex(int startIndex){ BEM_y:#
if(totalCount <= 0) ct='Z E
this.startIndex = 0; j3 d=O!
elseif(startIndex >= totalCount) (5[|h
this.startIndex = indexes ^/`:o}7K7
J5Rr7=:*S
[indexes.length - 1]; DE3>F^ j
elseif(startIndex < 0) [oN}zZP]
this.startIndex = 0; !Irmc*;QE
else{ 9hG)9X4
this.startIndex = indexes Sqj'2<~W
is&A_C7yg
[startIndex / pageSize]; s6<`#KFAg
} UEmNT9V
} S%n5,vwE
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publicint getNextIndex(){ Isv@V.
int nextIndex = getStartIndex() + et]-;(M
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$)
pageSize; "<b~pfCOQk
if(nextIndex >= totalCount) bv$g$
return getStartIndex(); 5^'PjtW6
else -DDH)VO
return nextIndex; +f/G2qY!t
} 4~-"k{Xt
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publicint getPreviousIndex(){ Qj(q)!Ku
int previousIndex = getStartIndex() - .um]1_= \
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pageSize; < V) T_
if(previousIndex < 0) R?3^Kx
return0; S N_!o2F2
else <(x[Qp/5P
return previousIndex; 1c);![O
} De`)`\U
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} \IY)2C<e
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抽象业务类 b*=eMcd
java代码: PY7j uS[+
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/** *IWO ,!
* Created on 2005-7-12 z VleJ!d
*/ @F)51$Ld
package com.javaeye.common.business; un|+YqLf
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import java.io.Serializable; @f442@_4
import java.util.List; f h05*]r
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import org.hibernate.Criteria; n1K"VjZk
import org.hibernate.HibernateException; g(xuA^~J
import org.hibernate.Session; w J
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import org.hibernate.criterion.DetachedCriteria; Dg~r%F
import org.hibernate.criterion.Projections; gaBt;@?:Q
import -;=0dfC(
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org.springframework.orm.hibernate3.HibernateCallback; tcOgF:
import F
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org.springframework.orm.hibernate3.support.HibernateDaoS aRg/oA4}
2ILMf?}
upport; vum6O3
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import com.javaeye.common.util.PaginationSupport; JmB7tRM8
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public abstract class AbstractManager extends UO^"<0u
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HibernateDaoSupport { v-2_#
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privateboolean cacheQueries = false; ~PYMtg=i
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privateString queryCacheRegion; {8D`A;KD
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publicvoid setCacheQueries(boolean $ ;cZq
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cacheQueries){ u 0KVp6`
this.cacheQueries = cacheQueries; s.z (1MB]
} '&@'V5}C{
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publicvoid setQueryCacheRegion(String GkqKIs
)s^D}I(
queryCacheRegion){ EjLj5Z/q
this.queryCacheRegion = zs!,PQF(
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queryCacheRegion; A&_H%]{<:
} AcV 2l
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publicvoid save(finalObject entity){ $/</J]2`;
getHibernateTemplate().save(entity); FbB^$ ]*
} h-u63b1"?
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publicvoid persist(finalObject entity){ cLl=?^DB
getHibernateTemplate().save(entity); K#q1/2
} _j t>%v4}4
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publicvoid update(finalObject entity){ V+My]9ki
getHibernateTemplate().update(entity); urmx})=
} !v(j#N< m
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publicvoid delete(finalObject entity){ SQ7Ws u>T@
getHibernateTemplate().delete(entity); 7i?"akr4
} ximW!y7
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publicObject load(finalClass entity, u*:B 9E
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finalSerializable id){ Z,AF^,H[
return getHibernateTemplate().load X5i?Bb.
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(entity, id); sd|5oz)
} kj_o I5<'
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publicObject get(finalClass entity, -_&"Q4FR;+
5,
finalSerializable id){ ?K]Cs&E4
return getHibernateTemplate().get 'J(rIH3U
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(entity, id); M6J~%qF^
} $g? ]9}p
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publicList findAll(finalClass entity){ le1
return getHibernateTemplate().find("from h:{rjXK
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" + entity.getName()); i>Wsc?
} ?K9&ye_rgw
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publicList findByNamedQuery(finalString 82ay("ZY
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namedQuery){ ,z A9*
return getHibernateTemplate h!l&S2)D`
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().findByNamedQuery(namedQuery); ~)Z{ Yj9)S
} ia#Z$I6
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publicList findByNamedQuery(finalString query, F*""n
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finalObject parameter){ +u+|9@
return getHibernateTemplate l* C>
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().findByNamedQuery(query, parameter); XV)<Oav s
} jI})\5<R
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publicList findByNamedQuery(finalString query, _XLGXJ[B
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finalObject[] parameters){ O |45r
return getHibernateTemplate ^e*Tg&
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().findByNamedQuery(query, parameters); >TZ 'V,
} 2>%|PQ
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publicList find(finalString query){ )UBU|uYR\
return getHibernateTemplate().find %eK=5Er jx
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(query); x"/DCcZ
} k:1p:&*m
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publicList find(finalString query, finalObject C(N' +VV_
/ =]h@m-`
parameter){ SP}!v5.
return getHibernateTemplate().find (>~:1
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(query, parameter); s2SxMFDP
} q [}<LU
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public PaginationSupport findPageByCriteria `6bIxb{
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(final DetachedCriteria detachedCriteria){ _p;>]0cc.
return findPageByCriteria '0\,waEu
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 0j{Rsy
} 'mwgHo<u
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public PaginationSupport findPageByCriteria "==fWf
v)+E!"R3.
(final DetachedCriteria detachedCriteria, finalint jh7-Fl`
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startIndex){ zG
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return findPageByCriteria ANIx0*Yl(
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(detachedCriteria, PaginationSupport.PAGESIZE, @4)NxdOE
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startIndex); !U6q;'
)-
} %5g(|Y]
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public PaginationSupport findPageByCriteria :%&|5Ytb
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(final DetachedCriteria detachedCriteria, finalint CjFnE
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pageSize, d_7v 1)j
finalint startIndex){ "2l$}G
return(PaginationSupport) "Zh3,
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getHibernateTemplate().execute(new HibernateCallback(){ |DUWB;
publicObject doInHibernate uU$YN-
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(Session session)throws HibernateException { HB|R1<t;HB
Criteria criteria = io&FW!J.
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detachedCriteria.getExecutableCriteria(session); dG8_3T}i
int totalCount = ww? AGd
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((Integer) criteria.setProjection(Projections.rowCount d76nyQKK
a:v5(@8
()).uniqueResult()).intValue(); LE@<)}Au^
criteria.setProjection :P'M|U
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(null); 4D'AAr57
List items = p<Oz"6_/~
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criteria.setFirstResult(startIndex).setMaxResults T]_]{%z
"26=@Q^Y
(pageSize).list();
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PaginationSupport ps = cFD3
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new PaginationSupport(items, totalCount, pageSize, l('@~-Zy
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startIndex); SH1S_EQ<
return ps; @ajt
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} [_BQ%7DU
}, true); I4"(4u@P
} `1`Qu!
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public List findAllByCriteria(final {P{h|+;
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DetachedCriteria detachedCriteria){ wU}%]FqtZ=
return(List) getHibernateTemplate &7J-m4BI
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().execute(new HibernateCallback(){ S+ 3lX7
publicObject doInHibernate u7/]Go44
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(Session session)throws HibernateException { ]t"X~
Criteria criteria = %lK/2-
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detachedCriteria.getExecutableCriteria(session); <9 dfbI)
return criteria.list(); YB}m1g`
} 4{lrtNd~K
}, true); ;Yve m
} goqm6L^Cu
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public int getCountByCriteria(final $Ph#pM(
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DetachedCriteria detachedCriteria){ Tlm::S
Integer count = (Integer) Fks #Y1rI
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getHibernateTemplate().execute(new HibernateCallback(){ .du2;`[$r
publicObject doInHibernate n&%0G2m:
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(Session session)throws HibernateException { (V x2*Aw]
Criteria criteria = OLZs}N+ ;]
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detachedCriteria.getExecutableCriteria(session); ucYweXsO3
return 5W!#,jz
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criteria.setProjection(Projections.rowCount WYN0,rv1:+
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()).uniqueResult(); j Gp&P
} 5Q/jI$^h0Z
}, true); GIvl|
return count.intValue(); KvH t`
} -pHUC't
} AM0CIRX$
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用户在web层构造查询条件detachedCriteria,和可选的 5AK@e|G$w
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 YuUJgt .1
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PaginationSupport的实例ps。 I {%Y0S
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ps.getItems()得到已分页好的结果集 VkkC;/BBW
ps.getIndexes()得到分页索引的数组 @u@,Edh
ps.getTotalCount()得到总结果数 u]*f^/6Q
ps.getStartIndex()当前分页索引 l@0${&n
ps.getNextIndex()下一页索引 Vq599M:)V
ps.getPreviousIndex()上一页索引 l*
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 >a;LBQ0
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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 I|l5e2j
mX%T"_^
一下代码重构了。 pr[V*C/
JM7FVB
我把原本我的做法也提供出来供大家讨论吧: {DD #&B
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首先,为了实现分页查询,我封装了一个Page类: rvacCwI
java代码: P(UY}oU
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/*Created on 2005-4-14*/ j 8)*'T
package org.flyware.util.page; ,e^~(ITaq
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/** I7\T :Q[
* @author Joa qe5;Pq !G
* _^g4/G#13c
*/ IF cre
publicclass Page { )KY4BBc
t`Rbn{
/** imply if the page has previous page */ `GSl}A
privateboolean hasPrePage; r~G amjS
>`l^
C
/** imply if the page has next page */ ;H3~r^>c
privateboolean hasNextPage; ;jJ4H+8
J|F!$m{
/** the number of every page */ ?[|A sw1t
privateint everyPage; "(iDUl
au]W*;x
/** the total page number */ $:yIe.F
privateint totalPage; IE3GZk+a~
Y4+]5;B8
/** the number of current page */ W!"Oho'
privateint currentPage; 1gnLKf c
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/** the begin index of the records by the current };R2M
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query */ _f~$iY
privateint beginIndex; bk1.H@8
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/** The default constructor */ vQG v4
public Page(){ LM(r3sonb
W7c
B
} VN0KK
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/** construct the page by everyPage PC\p>6xT
* @param everyPage jrxq558
* */ wA"d?x
public Page(int everyPage){ v$xurj:v#i
this.everyPage = everyPage;
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} <(_Tanx9Q
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/** The whole constructor */ +tlBOl$
public Page(boolean hasPrePage, boolean hasNextPage, Ljiw9*ZI
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int everyPage, int totalPage, x+TdTe;p
int currentPage, int beginIndex){ da~_(giD*
this.hasPrePage = hasPrePage; G^cMY$?99
this.hasNextPage = hasNextPage; /;TtMQt
this.everyPage = everyPage; "[rz*[o8I
this.totalPage = totalPage; &grvlK
this.currentPage = currentPage; E,dUO;
this.beginIndex = beginIndex; lWH#/5`h
} Bt#'6::
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/** yeMe2Zx
* @return `\P1Ff@z0
* Returns the beginIndex. bPif"dhHe
*/ ?D,j!Hy
publicint getBeginIndex(){ #C'E'g0
return beginIndex; tqCwbi
} (sI`FW_
=.OzpV)=V
/** Wsp c;]&
* @param beginIndex ;" D~F
* The beginIndex to set. R+t]]n6#
*/ `mI5Z*]-
publicvoid setBeginIndex(int beginIndex){ 8GRB6-.h
this.beginIndex = beginIndex; \3]O?'
} $BT[fJ'k
GIT"J}b}
/** y(/5l
* @return =c$x xEDD
* Returns the currentPage. "Bwmq9Jq
*/ 15En$6>
publicint getCurrentPage(){ :>0,MO.^~K
return currentPage; MBLDxsZ-
} 6tjV^sjs
}#;.b'`
/** K<r5jb
* @param currentPage p] N/]2rR
* The currentPage to set. @h_ bXo
*/ ,`OQAJ)>
publicvoid setCurrentPage(int currentPage){ 4;>HBCM4-
this.currentPage = currentPage; -E3cS
} s|:1z"q
uL@%M8n
/** DF>tQ
* @return 9ZG:2ncdJ
* Returns the everyPage. lFduX D
*/ xX9snSGz
publicint getEveryPage(){ dz>Jl},`k
return everyPage; X 5X D1[
}
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/** RnU7|p{
* @param everyPage p@Cas
* The everyPage to set. KT*>OYI
*/ eE=2~
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publicvoid setEveryPage(int everyPage){ >4-9 @i0FV
this.everyPage = everyPage; *0eV9!y
} =9`UcTSi6p
(2QfH$HEk
/** >qOj^WO~
* @return w (z=xO
* Returns the hasNextPage. (+cZP&o
*/ ?FUK_]
publicboolean getHasNextPage(){ +]zRn
return hasNextPage; #D%6b
} Qca3{|r`
"nb.!OG~(
/** ~R~.D
* @param hasNextPage ~)`\j
* The hasNextPage to set. 61_-G#W
*/ 7-Oa34ba+
publicvoid setHasNextPage(boolean hasNextPage){ ^E Rdf2
this.hasNextPage = hasNextPage; uFb
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} g]c6_DMfb1
$o;c:Kh$$
/** D^V)$ME
* @return >p0,]-.J,r
* Returns the hasPrePage. WC37=8mA
*/ <%`Rku
publicboolean getHasPrePage(){ B"\9sl X
return hasPrePage; "wg$ H1K
} AL^tUcl
W}2!~ep!
/** "vQ%`
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* @param hasPrePage RLL%l
* The hasPrePage to set. A%7f;&x!
*/ J .TK<!
publicvoid setHasPrePage(boolean hasPrePage){ $~/cxLcT
this.hasPrePage = hasPrePage; r\FZ-gk}Q
} Ewq@>$_!
wHQ$xO;vD'
/** =au!rda
* @return Returns the totalPage. 6Z' K1
* ?G!~&
*/ @V:Y%#%
publicint getTotalPage(){ z}.6yHS
return totalPage; Rm79mh9
} }
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?*yB&(a:8
/** *h=>*t?I2
* @param totalPage q86}'dFw{
* The totalPage to set. ;m>/tD%
*/ wfEL
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publicvoid setTotalPage(int totalPage){ ~e]B[>PT
this.totalPage = totalPage; zxIP-QaA
} Y*p<\{,oC
U6*[}Ww
} ' (XB|5
*]h"J]
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 0sH~yvM5
|HYST`
个PageUtil,负责对Page对象进行构造: %6rSLBw3
java代码: FE^/us7r
GG<0k\RN
zS|4@t\__
/*Created on 2005-4-14*/ Njr;Wa.r+
package org.flyware.util.page; cQ1Axs TO
-$:*!55:j
import org.apache.commons.logging.Log; S@S4<R1{\
import org.apache.commons.logging.LogFactory; ys>n%24qP
bKK'U4
/** s^IC]sW\%
* @author Joa r\F2X J^
* $F9w0kz:,*
*/ >3B{sn}
publicclass PageUtil { 7CSz
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privatestaticfinal Log logger = LogFactory.getLog @ <2y+_e
rPyjr(I"_
(PageUtil.class); JhwHsx/
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/** DTM(SN8R+n
* Use the origin page to create a new page "aI)LlyCY
* @param page i>[xN[U(
* @param totalRecords M*D_pn&
* @return Tp{jR<
*/ 8!3 q:8y8
publicstatic Page createPage(Page page, int TOKt{`2}
_e;bB?S
totalRecords){ xgj'um
return createPage(page.getEveryPage(), T+zhj++
TbT/ 5W3
page.getCurrentPage(), totalRecords); 5mpql[v3P
} &~/g[\Y
2RF3pIFrm
/** [g<gu~
* the basic page utils not including exception f(eXny@Y
';8 ,RTe
handler ;S$
* @param everyPage L;?F^RK{U
* @param currentPage cJ@fJ|
* @param totalRecords T,uF^%$@AQ
* @return page m9sck:g#L1
*/ P]y{3y:XxM
publicstatic Page createPage(int everyPage, int R@5eHP^
hCF_pt+
currentPage, int totalRecords){ F%&lM[N%
everyPage = getEveryPage(everyPage); IemhHf ^l
currentPage = getCurrentPage(currentPage); 4q7H
int beginIndex = getBeginIndex(everyPage, C;/ONF
.|g@#XIwe#
currentPage); Mt`LOdiC_
int totalPage = getTotalPage(everyPage, 5
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nvLdgu4P>
totalRecords); <pa-C2Ky
boolean hasNextPage = hasNextPage(currentPage, IAMa
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totalPage); `$FX%p
boolean hasPrePage = hasPrePage(currentPage); ^>!&]@
*S}CiwW>/
returnnew Page(hasPrePage, hasNextPage, KehM.c^
everyPage, totalPage, zDtC]y'
currentPage, >R6mI
I3r")}P
beginIndex); q UmSB"#Z
} k:j_:C&.
pM+9K:^B
privatestaticint getEveryPage(int everyPage){ =-/'$7R,
return everyPage == 0 ? 10 : everyPage; {d xl8~/I
} 7G;1n0m-T
ml^=y~J[
privatestaticint getCurrentPage(int currentPage){ tN4&#YK<
return currentPage == 0 ? 1 : currentPage; y4|<+9<7
} ^'tT_
gT
?SO!INJ
privatestaticint getBeginIndex(int everyPage, int zh=0zJ
@6+_0^
currentPage){ /U!B2%vq_
return(currentPage - 1) * everyPage; st)v'ce,
} pCo3%(
lfCr`[!E
privatestaticint getTotalPage(int everyPage, int ;/wH/!b
LWhy5H;Es
totalRecords){ [*(1~PrlO,
int totalPage = 0; 1BW 9,Xr
jVOq/o
if(totalRecords % everyPage == 0) ?f3R+4
totalPage = totalRecords / everyPage; 40`Qsv0#
else a JjUy%
totalPage = totalRecords / everyPage + 1 ; /=AFle2(
FW;}S9u3
return totalPage; -:'%YHxX
} q "T?
)F&.0 '
privatestaticboolean hasPrePage(int currentPage){ \<xo`2b
return currentPage == 1 ? false : true; )16+Pm8
} 5Uy*^C7M^
tq~f9EvC
privatestaticboolean hasNextPage(int currentPage, W-|CK&1
<P0 P*>M
int totalPage){ "[fPzIP9
return currentPage == totalPage || totalPage == YryMB,\
pp1Kor
0 ? false : true; sUmpf 4/
} ,?qJAV~>
NKB["+S<
lqh:c
} \}k R'l
gpzFY"MS=
.mqMzV
NX(+%EBcA
''q;yKpaz
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 >Je$WE3
)G, S7A
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 kCz2uG)l
;=^J_2ls
做法如下: 83_mR*tGNp
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 R)$]r>YZF
<Z_\2
YWA
的信息,和一个结果集List: TC'SDDX
java代码: -$=RQH$9
aQY.96yo
XVfUr\=,T
/*Created on 2005-6-13*/ 9
;uw3vI%
package com.adt.bo; [N%InsA9k
Ez-AQ'
import java.util.List; /u90)x
(vi^ t{k
import org.flyware.util.page.Page; lFIaC}
&YD+s%OL
/** .=G3wox3
* @author Joa s[UV(::E
*/ hR2 R
publicclass Result { IN#/~[W
QqW N7y_9
private Page page; Ge?DD,ac
)g
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private List content; XH*(zTd(?
,-k?"|tQ
/** "d~<{(:N^
* The default constructor =^*EM<WG)
*/ ?y>v"1+
public Result(){ a Iyzt
super(); 1B&XM^>/
} HpUJ_pZ
o.|36#Fa
/** Er$&}9G+-
* The constructor using fields !nsr( 7X2
* 32anmVnf
* @param page P92pQ_W
* @param content I~p*~mLh'
*/ Lr\(7r
public Result(Page page, List content){ )w&|VvM )L
this.page = page; [4B(rra
this.content = content; vfhoN]v
} =c#mR" 1
|t3}>+"?z
/** g}hNsU=$5~
* @return Returns the content. +gBDE:
*/ mKV31wvK}
publicList getContent(){ pK_zq
return content; rij%l+%@#
} iny/K/5bf
l9+CJAmq
/** >}]bKq
* @return Returns the page. SbMRrWy
*/ JW2f 6!b
public Page getPage(){ eej#14&
return page; asp\4-?$o
} @{3_7
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/** )G]J@36
* @param content Q($@{[lT
* The content to set.
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*/ C deV3
public void setContent(List content){ tId,Q>zH
this.content = content; lq`7$7-4
} lY,9bSF$
QP!;Gwqr
/** 1{cF/ :o
* @param page lSd tw b
* The page to set. j 7O!uUQQ
*/ UaQW<6+
publicvoid setPage(Page page){ z1tCSt}7f
this.page = page; ^n4aoj
} B"*PBJuOA
} ga;t`5+d
F60m]NUM)c
KqaEHL
K@osD7-
=R9`to|
2. 编写业务逻辑接口,并实现它(UserManager, _XrlCLp: d
{Q]7!/>>
UserManagerImpl) 6BQq|:U
java代码: YCzH@94QeV
Sv>CVp*
qla=LS\-A+
/*Created on 2005-7-15*/
~Z#\f5yv@
package com.adt.service; !l.^]|
Ln\Gv/)
import net.sf.hibernate.HibernateException; o(3OChH
LT,zk)5
import org.flyware.util.page.Page; { M[iYFg=
B4m34)EOE
import com.adt.bo.Result; =PjdL32
>%t5j?p
/** i8R2Y9Q*O
* @author Joa lqAv
*/ Nlc3S+$`z
publicinterface UserManager { NcSi %]
.)FFl
public Result listUser(Page page)throws
^fS_h`B
vsI|HxpyC,
HibernateException; 4Xn-L&0z
;1TQr3w
} #Wv8+&n
uBM%E OE
4QNwu7TeR
QNj6ETB-d
sN1I+X
java代码: poi39B/Vt
Ipow
Jw^
hrfSe $8
/*Created on 2005-7-15*/ &&96kg3
package com.adt.service.impl; '0qKb*
akgvV~5
import java.util.List; +~lPf.
"#%9dWy
import net.sf.hibernate.HibernateException; k>\s6
6?0QzSpfC#
import org.flyware.util.page.Page; cI<T/~P
import org.flyware.util.page.PageUtil; +]C|y ,r
U\YzE.G1]S
import com.adt.bo.Result; g9=O<u#
import com.adt.dao.UserDAO; #'y^@90R
import com.adt.exception.ObjectNotFoundException; N\hHu6
import com.adt.service.UserManager; h>|IA@;|f
P>*`<$FR
/** `DP4u\6_
* @author Joa {E1^Wn1M
*/ dJ{'b'#
publicclass UserManagerImpl implements UserManager { H|;BT
3J^'x
private UserDAO userDAO; jrYA5>=>#
)OQih+#?W
/** $*+UX
* @param userDAO The userDAO to set. 6bbzgULl
*/ [Ue"#w
publicvoid setUserDAO(UserDAO userDAO){ :&O6Y-/B
this.userDAO = userDAO; @Y&(1Wl
} \e?w8R.6w^
G`u";w_
/* (non-Javadoc) $n<X'7@0
* @see com.adt.service.UserManager#listUser z'Fu} ho
`ItPTSOi
(org.flyware.util.page.Page) }/%^;@q ;
*/ U {sT %G
public Result listUser(Page page)throws lhFv2.qR
~NwX,-ri
HibernateException, ObjectNotFoundException { )TkXdA?.
int totalRecords = userDAO.getUserCount(); 82=>I*0Q
if(totalRecords == 0) mH4Jl1S&
throw new ObjectNotFoundException .W0;Vhw"
*U|2u+| F
("userNotExist"); <%LN3T
page = PageUtil.createPage(page, totalRecords); I h 19&D
List users = userDAO.getUserByPage(page); "nn>I}jK
returnnew Result(page, users); hr GfA
} fq[,9lK
9m2Yrj93
} )^Md ^\?
/2]=.bLwz
:x_;-
?Ns aZ
uhr&P4EW
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 t|k-Bh:x
2?9gf,U
询,接下来编写UserDAO的代码: Y:K1v:Knw
3. UserDAO 和 UserDAOImpl: f}zv@6#&
java代码: ZG-[Gz
ZfWF2%]<
X}j_k=, C
/*Created on 2005-7-15*/ 0tah$;c
e
package com.adt.dao; os`#:Ao5
>l0D,-O]m
import java.util.List; /Os;, g
@:G#[>nKe
import org.flyware.util.page.Page; L ]Dl}z
7 T9 Mo
.
import net.sf.hibernate.HibernateException;
*4{GID
$pYT#_P!/
/** pU5t,
* @author Joa /m+\oZ
]d
*/ WB>M7MI%
publicinterface UserDAO extends BaseDAO { ^CQVqa${]
UhF+},gU
publicList getUserByName(String name)throws =%G<S'2'
3h>56{P
HibernateException; :~dI2e\:
+ |d[q?
publicint getUserCount()throws HibernateException; $_0~Jzt,
]$
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publicList getUserByPage(Page page)throws [n9X5qG~
*D$Hd">X
HibernateException; *lws7R
d^YM@>%
} N'e3<
!$^LTBOH3
:=^_N}
VT`C<'
9~C$C
java代码: :7Smsc"B!
y6 _,U/9
^# gR"\F`d
/*Created on 2005-7-15*/ j`$d W H/2
package com.adt.dao.impl; zXx)xIO
;bxL$1
import java.util.List; 8X2NEVH]
Lb%Wz*Fa%!
import org.flyware.util.page.Page; uS,XQy2
VsMTzGr
import net.sf.hibernate.HibernateException; ]2o? Gnn@
import net.sf.hibernate.Query; zz~AoX7V6
]&RC<imq
import com.adt.dao.UserDAO; 8 ,<F102(
;Jq 7E
/** c2fbqM~
* @author Joa #99fFs`w
*/ d%='W|i\p&
public class UserDAOImpl extends BaseDAOHibernateImpl N T<>LWo
auV<=1<zJ
implements UserDAO { pSlosv(6
bB`p-1
/* (non-Javadoc) 4!
V--F
* @see com.adt.dao.UserDAO#getUserByName u!WjG@
Yr9!</;T
(java.lang.String) {E+o+2L
*/ idh5neyL
publicList getUserByName(String name)throws } :8{z`4H
wnoL<p
HibernateException { V:vYS
String querySentence = "FROM user in class UL
v*k}{M
com.adt.po.User WHERE user.name=:name"; h1'j1uI
Query query = getSession().createQuery (lBwkQNQGd
^saH^kg1"
(querySentence); <;
(pol|
query.setParameter("name", name); BLskUrPF
return query.list(); @z!|HLD+
} :CJ]^v
x^ruPiH
/* (non-Javadoc) 0X"D!G):
* @see com.adt.dao.UserDAO#getUserCount() Xitsbf=Gg
*/ M@b:~mI[sw
publicint getUserCount()throws HibernateException { J$X{4
int count = 0; {"x8q
String querySentence = "SELECT count(*) FROM 0j)D[K
"<y0D!&
user in class com.adt.po.User"; 6!GO{2d"
Query query = getSession().createQuery OcWzo#q4[
y6*9, CF
(querySentence); 6+hx64 =
count = ((Integer)query.iterate().next 2,,t+8"`
L]C|&KP
()).intValue();
|wFfVDp
return count; m$X0O_*A
} qz
.{[l
+7]]=e<[E
/* (non-Javadoc) VS{po:]A
* @see com.adt.dao.UserDAO#getUserByPage .+ w#n<
|6d0,muN
(org.flyware.util.page.Page) CtO `t5
*/ U94Tp A6
publicList getUserByPage(Page page)throws O!7v&$]1
~Kr_[X:d5
HibernateException { Nhnw'9
String querySentence = "FROM user in class );zLy?n
hkhk,bhI
com.adt.po.User"; wNX2*
Query query = getSession().createQuery }c$@0x;YQ
x8]5> G8(r
(querySentence); l&f"qF?
query.setFirstResult(page.getBeginIndex()) 1>BY:xZr
.setMaxResults(page.getEveryPage()); ^mA ^7jB
return query.list(); np#RBy
} &2EimP
cU^Z=B
} L&WhX3$u
p*_^JU(<p
ksB-fOv*N
)ZcwG(o0
@FBlF$vG
至此,一个完整的分页程序完成。前台的只需要调用 0+]ol:i
XsVp7zk\
userManager.listUser(page)即可得到一个Page对象和结果集对象 y)B>g/Hoh
*)6:yn
的综合体,而传入的参数page对象则可以由前台传入,如果用 O~1vX9
).BZPyV<
webwork,甚至可以直接在配置文件中指定。 ~$O.KF:
#:yh2y7a%
下面给出一个webwork调用示例: X?'v FC
java代码: (rM-~h6g
sr+Y"R
4*K~6Vh
/*Created on 2005-6-17*/ 5w#
Ceg9
package com.adt.action.user; 2tq~NA\#t
Kn!n}GtR
import java.util.List; 8 )W{C>
?%RN? O(
import org.apache.commons.logging.Log; VX!UT=;
import org.apache.commons.logging.LogFactory; F"k.1.
import org.flyware.util.page.Page; ?Z]5
[
|@a.dgz,
import com.adt.bo.Result; 9F&s9(=\
import com.adt.service.UserService;
c%N8|!e
import com.opensymphony.xwork.Action; P}AfXgr
HX(Z(rcI
/** m|}};8
* @author Joa :UMtknV
*/ oY#62&wk4
publicclass ListUser implementsAction{ |N{?LKR
%
zuq7 x7
privatestaticfinal Log logger = LogFactory.getLog :slVja$e
=Qa*-*
(ListUser.class); %SHjJCS3
yt+"\d
private UserService userService; tdl Y
<d$L}uQwg
private Page page; #fy#G}c
?-y!FD}m&
privateList users; Ax9a5;5WM
LZ97nvK
/* km)5?
* (non-Javadoc) &rcC7v K9
* /ynvQ1#uA
* @see com.opensymphony.xwork.Action#execute() >8pmClVvmR
*/ $<y10DfO
publicString execute()throwsException{ zPC&p{S>
Result result = userService.listUser(page); Dd(#
page = result.getPage(); B_^ ~5_0:
users = result.getContent(); %(c5T)B9
return SUCCESS; @bc=O1vX~;
} 8b^v@|)N
y}'c)u
/** %,l+?fF
* @return Returns the page. eX;Tufe*(Q
*/ px!TRbf
public Page getPage(){ j"8 f,er
return page; @dy<=bh~
} `eF&|3!IYQ
PWwz<AI+
/** "1<>c/h
* @return Returns the users. <`B4+:;w6
*/ Qj?qWVapA
publicList getUsers(){ -FAAP&LG
return users; Au q)
} rj.]M6#
|
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/** b"au9:F4@7
* @param page IEx`W;V]K
* The page to set. Tn$/9<Q
*/ nK@RFU6
publicvoid setPage(Page page){ /_N*6a~
this.page = page; )9^0Qk' ]
} BD)5br].
rQ^X3J*`
/** peA}/Jc
* @param users E@/yg(?d=
* The users to set. =~OH.=9\
*/ NA%(ZRSg(
publicvoid setUsers(List users){ >O{U4_j@(
this.users = users; ^!={=No]
}
H%!ED1zpA
ZB+N[VJs)
/** wkO8
* @param userService ,?OV39h
* The userService to set. k/"^W.B aj
*/ .,)C^hs@
publicvoid setUserService(UserService userService){ Dlc=[kf9
this.userService = userService; z!z+E%H^
} (&25 8i,
} sHk,#EsKH
'nK(cKDIG
WBo|0(#
.>5KwEK~
7*!h:rg
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, M^i^_}~S;
;1S~'B&1Q
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 Mr5E\~K>s
@~4Q\^;NX
么只需要: e?Pzhha
java代码: m&GxLT6
(<= e?
.RI{\ i`
<?xml version="1.0"?> j k%MP6
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork j{.P'5e@pZ
$VWeo#b
1.0//EN" "http://www.opensymphony.com/xwork/xwork- B.wRZDEvc
VtNY~
1.0.dtd"> YLr<^G-v
aV^wTs#2I
<xwork> 8Z=d+}Gg<
//SH=>w2
<package name="user" extends="webwork- u7rA8u|TO
eXHk6[%[
interceptors"> +=XDNSw
(J c} K
<!-- The default interceptor stack name ZT
UaF4k j
MwoU>+XB
--> QB<9Be@e
<default-interceptor-ref =%p%+F@RlW
rf2+~B{$,
name="myDefaultWebStack"/> y7K&@Y
hAPWEh^
<action name="listUser" 6x1!!X+)+
.qjVw?E
class="com.adt.action.user.ListUser"> s0}OsHAj
<param #=tWjInm
qIbp0`m
name="page.everyPage">10</param> 0P(U^rkR~
<result /H_,1Fu|
>s@*S9cj:
name="success">/user/user_list.jsp</result> pEc|h*p8
</action> 8PWx>}XPt
54TW8y `h
</package> k{*IR
2v
^bd^]u:
</xwork> EhEUkZE3)
&<!DNXQ
<