Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 m<4tH5};d
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ",E$}=
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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 $kQQdF
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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 #)%dG3)e
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分页支持类: 3 _DJ
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java代码: 'khhn6itA
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package com.javaeye.common.util; s)~H_,
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import java.util.List; 6k\8ulHw
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publicclass PaginationSupport { \9.@Tg8`
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publicfinalstaticint PAGESIZE = 30; hKK"D:?PRs
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privateint pageSize = PAGESIZE; K&vqk/JW1
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privateList items; =G/`r!r*0I
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privateint totalCount; n<7R6)j6
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privateint[] indexes = newint[0]; G?yG|5.pU
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privateint startIndex = 0;
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public PaginationSupport(List items, int tFLdBv!=:^
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totalCount){ x
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setPageSize(PAGESIZE); ZS51QB
setTotalCount(totalCount); "L^Klk?Vn
setItems(items); Ipo?>To
setStartIndex(0); V?U->0>Z4
} J
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public PaginationSupport(List items, int rb_ cm
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totalCount, int startIndex){ e%#(:L
setPageSize(PAGESIZE); P?%kV
setTotalCount(totalCount); bp G`,[
setItems(items); 4:\1S~WW
setStartIndex(startIndex); ~e<l`rg#
} 7kmU/(8
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public PaginationSupport(List items, int Bbuy
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totalCount, int pageSize, int startIndex){ o~7~S
setPageSize(pageSize); (=:9pbP
setTotalCount(totalCount); ax{+7 k
setItems(items); Kn~f$1
setStartIndex(startIndex); W=YFe<Q
} %Od?(m"&
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publicList getItems(){ n"YY:Gm;8
return items; nbM[?=WS
} ]k~k6#),;
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publicvoid setItems(List items){ VfAC&3%M
this.items = items;
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} tRU+6D
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publicint getPageSize(){ 3=w$1.B d
return pageSize; vZj:\geV
} 6 R}]RuFQ
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publicvoid setPageSize(int pageSize){ HO ,z[6
this.pageSize = pageSize; nG<_&h
} SaKaN#C
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publicint getTotalCount(){ _@I<H\^
return totalCount; F9rxm
} +92/0
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publicvoid setTotalCount(int totalCount){ *nUD6(@g
if(totalCount > 0){ sE87}Lz
this.totalCount = totalCount; hKP7p
int count = totalCount / ,!U._ic'B
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pageSize; ^`ah\L
if(totalCount % pageSize > 0) : vN'eL|#
count++; *Dx&} "
indexes = newint[count]; b#;%TbDF
for(int i = 0; i < count; i++){ ` #Qlr+X
indexes = pageSize * !#0Lo->OO
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i; s=0z%~H
} >`Xikn(
}else{ po@=$HK
this.totalCount = 0; tU2 8l.
} h}PeXnRU
} qN h:;`
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publicint[] getIndexes(){ &,B\ig1Jf
return indexes; -#Xo^-&
} yPG,+uQ$.
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publicvoid setIndexes(int[] indexes){ !1
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this.indexes = indexes; QcBuUFf!c
} 5yPw[
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publicint getStartIndex(){ Db"jzMW.
return startIndex; _;baZ-
} yVQ0;h
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publicvoid setStartIndex(int startIndex){ ? <b>2j
if(totalCount <= 0) l-` M
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this.startIndex = 0; 'Rbv3U
elseif(startIndex >= totalCount) 13
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this.startIndex = indexes AlP}H~|M7
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[indexes.length - 1]; ;hP43Bi
elseif(startIndex < 0) F_>OpT
this.startIndex = 0; J3Ipk-'lx
else{ 64]_o/u5W4
this.startIndex = indexes F+yu[Dh:
*?sdWRbu}l
[startIndex / pageSize]; DC?U+
} d/I,`
} aLZza"W
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publicint getNextIndex(){ , y%!s27
int nextIndex = getStartIndex() + W&E?#=*X
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pageSize; bCWSh~
if(nextIndex >= totalCount) -'SpSy'_
return getStartIndex(); 38<!Dt+S(,
else xgsE JE
return nextIndex; fuRCM^U(
} 9FB k|g"U)
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publicint getPreviousIndex(){ +<#0V!DM
int previousIndex = getStartIndex() - Zy!^HS$
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pageSize; zx:Qz
if(previousIndex < 0) dk<) \C"
return0;
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else }<m'Nkz<X
return previousIndex; v|DgRPY
} y8oqCe)
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} N %;bV@A9
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抽象业务类 u!$+1fI>
java代码: 90Rz#qrI*
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/** &lnr?y^
* Created on 2005-7-12 ck0K^o v
*/ MaMP7O|W
package com.javaeye.common.business; rQE:rVKVh
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import java.io.Serializable; bF_SD\/
import java.util.List; k*xMe-
d v8q&_
import org.hibernate.Criteria; VsIDd}~C%
import org.hibernate.HibernateException; Y52f8qQq
import org.hibernate.Session; d@d\9*mn
import org.hibernate.criterion.DetachedCriteria; },r9f MJ
import org.hibernate.criterion.Projections; CEQs}bz
import JU>F&g/|
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org.springframework.orm.hibernate3.HibernateCallback; +!"GYPUXy
import 0oT~6BGm
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org.springframework.orm.hibernate3.support.HibernateDaoS B EN
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upport; NW=gi
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import com.javaeye.common.util.PaginationSupport; 86 $88`/2
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public abstract class AbstractManager extends qDlh6W?}k
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HibernateDaoSupport { H6o_*Y
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privateboolean cacheQueries = false; ?WEKRl
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privateString queryCacheRegion; M9C
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publicvoid setCacheQueries(boolean !xD$U/%c
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cacheQueries){ ?^}
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this.cacheQueries = cacheQueries; Ef)v("'w
} c_~tCKAZ
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publicvoid setQueryCacheRegion(String )
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queryCacheRegion){ @IE.@1
this.queryCacheRegion = {JGXdp:SB
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queryCacheRegion; $j(laD#AR
} }.L:(z^L,Y
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publicvoid save(finalObject entity){ #MyF 1E
getHibernateTemplate().save(entity); 8wH1x
.
} }uFV\1
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publicvoid persist(finalObject entity){ KA/~q"N
getHibernateTemplate().save(entity); (C9{|T+h
} :|&S7&l]
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publicvoid update(finalObject entity){ ]broU%#"
getHibernateTemplate().update(entity); r]3v.GZy
} MkK6.qV\z
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publicvoid delete(finalObject entity){ zE8qU;
getHibernateTemplate().delete(entity); s=8$h:^9>
} 16-1&WuY@
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publicObject load(finalClass entity, Y 8Dn&W
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finalSerializable id){ ]^>RBegJBO
return getHibernateTemplate().load \Dx5= Lh
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(entity, id); ;659E_y>
} hd>_K*oH
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publicObject get(finalClass entity, TQL_K8k@_
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finalSerializable id){ p!/ *(TT
return getHibernateTemplate().get a/Ik^:>m
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(entity, id); =a$7^d
} ecdM+kP
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publicList findAll(finalClass entity){ ?mbI6fYv
return getHibernateTemplate().find("from *r/o
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" + entity.getName()); .22}=z
} :G4)edwe
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publicList findByNamedQuery(finalString l\6.f_
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namedQuery){ (.~,I+Cz'
return getHibernateTemplate tSX,*cz
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().findByNamedQuery(namedQuery); z{(c-7*
} 0RF<:9@x2
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publicList findByNamedQuery(finalString query, zbZN-j#
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finalObject parameter){ V8947h|&
return getHibernateTemplate i Qa=4'9;
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().findByNamedQuery(query, parameter); H=@S+4_bK
} y{9<>28
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publicList findByNamedQuery(finalString query, S{S.H?{F
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finalObject[] parameters){ 1Gp|_8
return getHibernateTemplate 5e
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().findByNamedQuery(query, parameters); oTb4 T=
} um=qT)/D
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publicList find(finalString query){ K!O7q~s[D
return getHibernateTemplate().find -&0H Atc
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(query); 9RQw6rL
} {SwvUWOf"
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publicList find(finalString query, finalObject "vF7b|I
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parameter){ 8;fi1 "F;}
return getHibernateTemplate().find &d 6
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(query, parameter); /_ RrNzqy
} t}>"nr0
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public PaginationSupport findPageByCriteria AkX8v66:
l.%[s6
(final DetachedCriteria detachedCriteria){ 3h4'DQ.g
return findPageByCriteria EViDMp"
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ,K8(D<{
} =P`l+k3
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public PaginationSupport findPageByCriteria +<7a$/L?4
lQt* LWd[
(final DetachedCriteria detachedCriteria, finalint (R^Ca7F
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startIndex){ m ol|E={si
return findPageByCriteria 9D H}6fO
R zn%!d^$>
(detachedCriteria, PaginationSupport.PAGESIZE, !^IAn
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startIndex); (I ~r~5^
} 2|}KBny
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public PaginationSupport findPageByCriteria VN
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(final DetachedCriteria detachedCriteria, finalint <lf6gb
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pageSize, i1-wzI
finalint startIndex){
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return(PaginationSupport) (a@}J.lL
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getHibernateTemplate().execute(new HibernateCallback(){ 5u^;71
publicObject doInHibernate wKj0vMW
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(Session session)throws HibernateException { EM0]"s@Lf
Criteria criteria = BLcsIyq
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detachedCriteria.getExecutableCriteria(session); ~,O}wT6q
int totalCount = &/{x7;e
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((Integer) criteria.setProjection(Projections.rowCount ['\u?m
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()).uniqueResult()).intValue(); r|JZU
criteria.setProjection RtScv
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(null); b(?A^a
List items = +I_p\/J?w/
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criteria.setFirstResult(startIndex).setMaxResults }8?1)l
YN($rAkL
(pageSize).list(); 9/4Bx!~A
PaginationSupport ps = K91.-k3)$
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new PaginationSupport(items, totalCount, pageSize, WG(%Pkowv
u{(-`Al}L
startIndex); G&v. cF#Y'
return ps; VQ'DNv| 9
} h$I
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}, true); 707-iLkt.1
} |c3Yh,Sv
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public List findAllByCriteria(final e2*Fe9:
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DetachedCriteria detachedCriteria){ "M4gl
return(List) getHibernateTemplate Ilv
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().execute(new HibernateCallback(){ &Ez]pKjB
publicObject doInHibernate riY[p,
8VLD yX2-
(Session session)throws HibernateException { .80L>0
Criteria criteria = 7) e#b
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detachedCriteria.getExecutableCriteria(session); (Gpk;DD
return criteria.list(); t9+ME|
} V.12
}, true); u<a =TPAU
} sN9
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public int getCountByCriteria(final )1 =|\
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DetachedCriteria detachedCriteria){ .m
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Integer count = (Integer) 3FpS o+
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getHibernateTemplate().execute(new HibernateCallback(){ BHEZ<K[U
publicObject doInHibernate o7WK"E!pF'
k=r)kkO)
(Session session)throws HibernateException { Fmux#}Z
Criteria criteria = g
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detachedCriteria.getExecutableCriteria(session);
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return 84uHK)h<%
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criteria.setProjection(Projections.rowCount 39zwPoN>
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()).uniqueResult(); _Bhm\|t
} QY]G+3W
}, true); 3vK,vu q
return count.intValue(); c5e
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} ;[>g(W+
} hRWRXC9
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用户在web层构造查询条件detachedCriteria,和可选的 E6FT*}Q
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 %oY=.Ok ]
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PaginationSupport的实例ps。 $JTQA
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ps.getItems()得到已分页好的结果集 3.^Tm+ C
ps.getIndexes()得到分页索引的数组 '3MCb
ps.getTotalCount()得到总结果数 B}YpIb]d
ps.getStartIndex()当前分页索引 ozr82
ps.getNextIndex()下一页索引
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ps.getPreviousIndex()上一页索引 2/]74d8
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 />,Tq!i\4}
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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 '8|y^\
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一下代码重构了。 FNyr0!t,
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我把原本我的做法也提供出来供大家讨论吧: _ Db05:r@
keYvscRBI
首先,为了实现分页查询,我封装了一个Page类: :~1sF_
java代码: ,GH;jw)P
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/*Created on 2005-4-14*/ ic4mD:-up
package org.flyware.util.page; ,py:e>+^t
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/** ]U8VU
* @author Joa ?tJyQT
* 2W_p)8t>b
*/ DG!H8^
publicclass Page { [z^db0PU
v,] &[`
/** imply if the page has previous page */ c-a he;q
privateboolean hasPrePage; A"`^Abrm
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/** imply if the page has next page */ 3bGJ?hpp
privateboolean hasNextPage; { eU_
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/** the number of every page */ W=9Zl(2C
privateint everyPage; <&[`
+
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/** the total page number */ @8 c@H#H
privateint totalPage; iJh{,0))g
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/** the number of current page */ NdJ]\>5oN,
privateint currentPage; \
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\#biwX
/** the begin index of the records by the current 8cfsl lI
n=b!c@f4
query */ $~q{MX&J
privateint beginIndex; 6DHZ,gWq
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/** The default constructor */ y=9fuGL6
public Page(){ 9+(6/<
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}
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/** construct the page by everyPage J_+2]X7n
* @param everyPage ;ZJ. 7t'
* */ Gmu[UI}w8
public Page(int everyPage){ ih("`//nP
this.everyPage = everyPage; Eva&FHRTY
} Z wKX$(n
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/** The whole constructor */ &iD&C>;pf
public Page(boolean hasPrePage, boolean hasNextPage, 6a9:P@tY
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int everyPage, int totalPage, w:I!{iX
int currentPage, int beginIndex){ _$A?
this.hasPrePage = hasPrePage; iPCn-DoIS
this.hasNextPage = hasNextPage; 'xuxMav6m
this.everyPage = everyPage; w?_'sP{pd
this.totalPage = totalPage; fvta<
this.currentPage = currentPage; }x6)}sz7
this.beginIndex = beginIndex; rLeQBp'
} 43=)akJi
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/** ~2[kCuu
* @return L5:1dF
* Returns the beginIndex. Md9y:)P@Y
*/ ;<o?JM
publicint getBeginIndex(){ @@3NSKA
return beginIndex; BQ,749^S
} f^}n#
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/** Wf?[GO
* @param beginIndex ?W dY{;&
* The beginIndex to set. KWYjN
h#*
*/ /V/)A\g
publicvoid setBeginIndex(int beginIndex){ eF0FQlMe[
this.beginIndex = beginIndex; U
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} AH#a+<;a
v!DU ewz
/** y]! #$C /
* @return e~he#o[%a
* Returns the currentPage. >C{8}Lg-.
*/ 6*1f -IbV
publicint getCurrentPage(){ CE
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return currentPage; $<VH~Q<
} f\hQ>MLzt
#xR=U"
/** > B;YYj~f}
* @param currentPage Qo]qs+
* The currentPage to set. Dm?:j9o]g
*/ d=\TC'd"{
publicvoid setCurrentPage(int currentPage){ :rk6Stn$z
this.currentPage = currentPage; 2.{zfr
} vytO8m%U
7#&Q-3\:
/** y9T5
* @return f6(1jx"
* Returns the everyPage. .2|(!a9W
*/ 1TzwXX7
publicint getEveryPage(){ $PlMyLu7jc
return everyPage; mWP&N#vwh
} 6c>:h)?
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/** .f[z_%ar
* @param everyPage Gf!c
* The everyPage to set. I~HA
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*/ Yp3 y%n
publicvoid setEveryPage(int everyPage){ %<|<%~l&
this.everyPage = everyPage; n%}#e!
} {QN 5QGvK
H:Q4!<
/** benqm ~{\
* @return b!/-9{
* Returns the hasNextPage. %ol1WG 9
*/ svt3gkR0
publicboolean getHasNextPage(){ ?{L'd
return hasNextPage; 2H] 7 =j
} -U7,~z
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/** PgP\v -.
* @param hasNextPage
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* The hasNextPage to set. AnE]
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*/ @d0~'_vtB
publicvoid setHasNextPage(boolean hasNextPage){ oOLj?
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this.hasNextPage = hasNextPage; _$vbb#QXZG
} T'Jl,)"
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/** IQ$ 6}.
* @return wZ`*C
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* Returns the hasPrePage.
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*/ !4z vkJO
publicboolean getHasPrePage(){ 4kK_S.&
return hasPrePage; V~-tp^
} ^%\MOjSN
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/** Y!ypG-
* @param hasPrePage 2PNe~9)*#
* The hasPrePage to set. {g4w[F!77
*/ !X[7m
publicvoid setHasPrePage(boolean hasPrePage){
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this.hasPrePage = hasPrePage; X #$l7I9H
} Qip@L WvT
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/** NE &{_i!
* @return Returns the totalPage. #7YJ87<E
* gTLBR
*/ o>]z~^c
publicint getTotalPage(){ m*lcIa
return totalPage; yI-EF)A@;
} oykb8~u}}
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/** SC3_S.
* @param totalPage w xaMdA
* The totalPage to set. 4~;M\h
*/ Vhe$vH
publicvoid setTotalPage(int totalPage){ <1QXZfQ"
this.totalPage = totalPage; L)9Z Op5
} /*"pylm
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} g<$2#c}
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Q^xk]~G$(
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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 XBcbLF
4#t-?5"
个PageUtil,负责对Page对象进行构造: ttBqp|.?S
java代码: U?5G%o(q
:FmH=pI!=
Wn?),=WQ{
/*Created on 2005-4-14*/ lO 0}
package org.flyware.util.page; Jy('tfAHp
e:rbyzf#
import org.apache.commons.logging.Log; ]8'PLsS9<w
import org.apache.commons.logging.LogFactory; t4hc X[
&Du S*
/** PY+4OZ$
* @author Joa Qf'g2
\
* )NqRu+j
*/ 8NJT:6Q7l
publicclass PageUtil { $(*>]PC+)
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privatestaticfinal Log logger = LogFactory.getLog a#9pN?~
p|BoEITL
(PageUtil.class); AYp~;@
q_9 tbZ;
/** W u$yB!
* Use the origin page to create a new page V"} Jsr
* @param page )ac!@slb^7
* @param totalRecords +NiCt S
* @return /f AAQ7
*/ K(WKx7Kky^
publicstatic Page createPage(Page page, int vF[ 4kDHk
8f65;lyN
totalRecords){ h b8L[ 4
return createPage(page.getEveryPage(), y3PrLBTz
{9^p3Q+:P
page.getCurrentPage(), totalRecords); ,^DP
} B^ddi
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/** Ea-U+7JC
* the basic page utils not including exception Qam48XZ >
H4sc7-
handler }WBHuVcZG
* @param everyPage q1ZZ T"'
* @param currentPage lJT"aXt'M
* @param totalRecords 3iL\<^d*ht
* @return page !?+q7U
*/ IcGX~zWr
publicstatic Page createPage(int everyPage, int E\p"%
S.<4t*,
currentPage, int totalRecords){ wTG(U3{3K
everyPage = getEveryPage(everyPage); O}}rosA
currentPage = getCurrentPage(currentPage); :AI%{EV-L
int beginIndex = getBeginIndex(everyPage, :)&vf<JL
$TK= :8HY
currentPage); a(ml#-M
int totalPage = getTotalPage(everyPage, ~03MH'
F!*GrQms
totalRecords); ?zbW z=nq
boolean hasNextPage = hasNextPage(currentPage, wkV'']= Xg
BL"7_phM,
totalPage);
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boolean hasPrePage = hasPrePage(currentPage); @~UQU)-(
;P/ 4.|<
returnnew Page(hasPrePage, hasNextPage, GS}JyU
everyPage, totalPage, 9jM7z/Ff
currentPage, :M<] 6o
[9#zEURS
beginIndex); )OVa7[-T
} &
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vbZ!NO!H
privatestaticint getEveryPage(int everyPage){ S2nX{=
return everyPage == 0 ? 10 : everyPage; c&
bms)Jwa
} 5}Xi`'g,
NSH4 @x
privatestaticint getCurrentPage(int currentPage){ zgH*B*)bj
return currentPage == 0 ? 1 : currentPage; f*9O39&|
} 7q5*grm
Z&P\}mm
privatestaticint getBeginIndex(int everyPage, int mVh;=>8K
U4yl{?
currentPage){ pVrY';[,|
return(currentPage - 1) * everyPage; Uqy/~n-v<
} e0otr_)3F
%~PT7"4
privatestaticint getTotalPage(int everyPage, int i"
)_Xb_1
W8;!rFW
totalRecords){ B;W%P.<.
int totalPage = 0; jIVD i~Ld
2A:h&t/|C
if(totalRecords % everyPage == 0) =Vazxt@[
totalPage = totalRecords / everyPage; '
2O@
else nAAv42j[
totalPage = totalRecords / everyPage + 1 ; e?*Teb?R
Hrph>v
return totalPage; 6 . )Xeb"
} 3eXIo=
vLyazVj..
privatestaticboolean hasPrePage(int currentPage){ B&0W P5OF
return currentPage == 1 ? false : true; `(=Kp=b
} 7mMMVz2
cO5zg<wF
privatestaticboolean hasNextPage(int currentPage, +mzLOJed
$bFK2yx?=
int totalPage){ zNdkwj p+
return currentPage == totalPage || totalPage == ASre@pW
(Cfb8\~
0 ? false : true; QCE7VV1Rw
} 0Oc?:R'$
$(]nl%<Q
X{OWDy
} !2Z"Lm
85;bJfY
/]MelW
%Ta"H3ZW
x\f~Gtt7Y
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 Gn_DIFa
(V]3w
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 P)J-'2{
't0M+_J
做法如下: fwV2b<[
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 Y?3tf0t/
hpPacN
的信息,和一个结果集List: y$SUYG'v
java代码: |5O>7~Tp
$~W5! m
y_=y%
/*Created on 2005-6-13*/ #kq!{5,
package com.adt.bo; x\8|A
3}F>t{FDk
import java.util.List; El;"7Qn
<r$h =hM
import org.flyware.util.page.Page; MGt>:&s(]
#
#2'QNN
/** ck5cO-1>6
* @author Joa c@3 5\!9
*/ %Uz\P|6PO
publicclass Result { b/]4#?g
[H>u'fy:C
private Page page; 3?I!
FiUwy/,ZV
private List content; !*NDsC9
/UK]lP^w]!
/** C&MqH.K
* The default constructor #?jsC)
*/ Z?!AJY
public Result(){ 3IlVSR^py
super(); ,aC}0t
} :TG;W,`.V
c {%mi
/** -OlrA{=c_
* The constructor using fields Zd>sdS`#r
* QOSMV#Nw%
* @param page P=jsOuW
* @param content 4Z~ nWs
*/ -bzlp7q*
public Result(Page page, List content){ 5~@-LXqL
this.page = page; aaT3-][
this.content = content; cK u[4D{
} k'#3fz\
(EY@{'.&
/** 3?]81v/
* @return Returns the content. h%ys::\zF
*/ c&',#.9
publicList getContent(){ R^o535pozc
return content; Pd"c*n&9
} a'?;;ZC-
a(]&H
"
/** pka^7OWyN
* @return Returns the page. ~1wt=Ln>
*/ tjb$MW$('
public Page getPage(){ sA|SOAn
return page; T :d+Qz\
} xw
43P.
R P<M
/** ,#3Aaw
* @param content EHm*~Sd
* The content to set. e,_Sj(R8
*/ 0lg'QG>
public void setContent(List content){ (4/"uj5
this.content = content; `y.4FA4"8
} *u"%hXR
8:V,>PH
/** _uMG?Sbx
* @param page m[v0mXE
* The page to set. A_wf_.l4h
*/ Yz_}*
publicvoid setPage(Page page){ x-CjxU3
this.page = page; B #%QY\<X
} yj4"eDg]
} N{HAWB{
i~]60M>
9d#?,:JG
>*ls}
q^
w+
!c9
2. 编写业务逻辑接口,并实现它(UserManager, 1Ys=KA-!_x
yV:8>9wE8
UserManagerImpl) Su6kpC!EW
java代码: {] ]%0!n\
GEc-<`-
fGlvum
/*Created on 2005-7-15*/ 1n^N`lD8]6
package com.adt.service; 20|_wAA5
!<:Cd(bM
import net.sf.hibernate.HibernateException; XKky-LeJ
%"Um8`]FVg
import org.flyware.util.page.Page; P(k*SB|D
Twa(RjB<
import com.adt.bo.Result; Q^2dZXk~
Z%3CmKdeF
/** 9m$"B*&6G
* @author Joa V4V`0I
*/ -^m?%_<50l
publicinterface UserManager { 6)uBUM;i
5tbCx!tL
public Result listUser(Page page)throws 0q"4\#4l
`KA==;0
HibernateException; =M;F&;\8
D r(0w{5
} 3Jizv,?
SqPqL<,e
?g+3 URpK
lOVcXAe}
7gf(5p5ZV
java代码: q=88*Y
(x2?{\?
NgyEy n
\
/*Created on 2005-7-15*/
QvZ"{
package com.adt.service.impl; FJtmRPP[r
#U`AK9rP_g
import java.util.List; 1*hE bO
_dd! nU\A|
import net.sf.hibernate.HibernateException; kiM:(=5
8)9-*Bzj
import org.flyware.util.page.Page; YXWDbr:JX
import org.flyware.util.page.PageUtil; U|Fqna
v3Vve:}+
import com.adt.bo.Result; 3xs<w7
import com.adt.dao.UserDAO; Lf5zHUH
import com.adt.exception.ObjectNotFoundException; i;^lh]u
import com.adt.service.UserManager; ZMgsuzg
5`p9Xo>)yW
/** yR>P
* @author Joa j_so s%-
*/ g]vB\5uA:
publicclass UserManagerImpl implements UserManager { K{DC{yLu
N=1ue`i
private UserDAO userDAO; J"AR3b@,$?
~@c<5 -`{
/** (7G4 v
* @param userDAO The userDAO to set. E42)93~C
*/ <WIIurp
publicvoid setUserDAO(UserDAO userDAO){ BN79\rt
this.userDAO = userDAO; 8C*@d_=q
} NuR7pjNMZ
:38{YCN
/* (non-Javadoc) d|RUxNjM-J
* @see com.adt.service.UserManager#listUser ^>l <)$s
-8qCCV&1i
(org.flyware.util.page.Page) 1}\p:`
*/ 3Sfd|0^
public Result listUser(Page page)throws k^%=\c
8<Iq)A]'Z
HibernateException, ObjectNotFoundException { % vUU
Fub
int totalRecords = userDAO.getUserCount(); I9qZE=i
if(totalRecords == 0) _rYW|*cIF
throw new ObjectNotFoundException h-ii-c?R@0
(%L/|F_
("userNotExist"); 8C3oi&av/{
page = PageUtil.createPage(page, totalRecords); -yqgs>R(d
List users = userDAO.getUserByPage(page); >S:(BJMo
returnnew Result(page, users); \bd KLcKI,
} *`+zf7-f
zG_n x3
} %9>w|%+;U+
Yt#;
+*d5
TbD
fU|v[
.S|7$_9;b
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 sn:VM HrOT
j_g(6uZhz3
询,接下来编写UserDAO的代码: 6m?<"y8]
3. UserDAO 和 UserDAOImpl: XF(D%ygeC
java代码: =Iop
|-V:#1wR.]
6{.U7="
/*Created on 2005-7-15*/ (y]Z *p:EW
package com.adt.dao; qg#YQ'vWte
U_IGL
import java.util.List; LnE/62){N
,7@\e&/&
import org.flyware.util.page.Page; X,w X)9]J
L/ibnGhq]
import net.sf.hibernate.HibernateException; [>v1JN
`r SOt*<
/** yq;[1O_9C
* @author Joa 1=J& ^O{W
*/ i5TGK#3o
publicinterface UserDAO extends BaseDAO { ?:$
q~[LY
Kb+SssF
publicList getUserByName(String name)throws vgy.fP"@
MuD
? KK
HibernateException; phH@{mI
sA?8i:]O:
publicint getUserCount()throws HibernateException; m)L50ot:/
."ZG0Zg
publicList getUserByPage(Page page)throws k'O.1
QtnNc!,n
HibernateException; *90dkJZ.
_3 3 b %
} b_ TI_
ljK?2z>
`]W9Fj<1j
:-jbIpj'
qj~=qV0p
java代码: OS#aYER~/
>G|RVB
B$rhsK%
/*Created on 2005-7-15*/ y\_+,G0
package com.adt.dao.impl; FcM)v"bF&]
1?&|V1vc
import java.util.List;
gra6&&^"
;j1
SSHZ
import org.flyware.util.page.Page; ;av!fK
I^A>YJW
import net.sf.hibernate.HibernateException; ZXs,TaU
import net.sf.hibernate.Query; 3]vVuQK .
`C: 7N=9
import com.adt.dao.UserDAO; GU>j8.
gamB]FPZ
/** m?Y-1!E0
* @author Joa ~RVlc;W
*/ < +*
public class UserDAOImpl extends BaseDAOHibernateImpl =,zB|sjn
P+f}r^4}
implements UserDAO { Kfb(wW
[j/|)cj
/* (non-Javadoc) mQ`atFz:Z
* @see com.adt.dao.UserDAO#getUserByName wY ItG"+6
T9$~tv,5F
(java.lang.String) H(;@7dh
*/ !Np7mv\7
publicList getUserByName(String name)throws g "Du]_,
8gNTW7W/
HibernateException { YT8q0BR]
String querySentence = "FROM user in class :N<Qk
_fk}d[q0
com.adt.po.User WHERE user.name=:name"; gN<7(F
Query query = getSession().createQuery ]8%E'd
PsUO8g'\
(querySentence); 82,^Pu
query.setParameter("name", name); 1,=:an
return query.list(); )zO|m7
} 8F>9CO:&N
?{ '_4n3O
/* (non-Javadoc) ^^}htg
* @see com.adt.dao.UserDAO#getUserCount() 7NRa&W2
*/ Zocuc"j
publicint getUserCount()throws HibernateException { XFoSGqD
int count = 0; /#T {0GBXe
String querySentence = "SELECT count(*) FROM kHr-UJ!
r4P%.YO+X
user in class com.adt.po.User"; (.=Y_g.
Query query = getSession().createQuery R5e[cC8o.
l/(~Kf9eQG
(querySentence); ;N.dzH2yA
count = ((Integer)query.iterate().next ggPGKY-b=
\h'7[vkr
()).intValue(); =b*GV6b
return count; h'S0XU
;
} TP#Ncqh
Io<T'K
/* (non-Javadoc) "Q+wO+}6
* @see com.adt.dao.UserDAO#getUserByPage =KQIrS:
SM)"vr_
(org.flyware.util.page.Page) 69$R.
*/ EE]xZz>o
publicList getUserByPage(Page page)throws 1/mBp+D
>[wxZ5))
HibernateException { h{7>>
String querySentence = "FROM user in class `\(co;:
4~1b
com.adt.po.User"; KKk~vwW
Query query = getSession().createQuery }JtcAuQt
Z{vc6oj
(querySentence); u:J(0re
query.setFirstResult(page.getBeginIndex()) TI8\qIW
.setMaxResults(page.getEveryPage()); 5yt= ~
return query.list(); i
Ehc<
} G HQ~{
(&79}IEd
} .*6NqX$
'eBD/w5U
~roNe|P
)0E_Y@
'%/=\Q`
至此,一个完整的分页程序完成。前台的只需要调用 -cU bIbW
*2/qm:gB
userManager.listUser(page)即可得到一个Page对象和结果集对象 =U~53Tg
KsIHJr7-
的综合体,而传入的参数page对象则可以由前台传入,如果用 $yU}56(z~
&;?+ ^L>
webwork,甚至可以直接在配置文件中指定。 BYdGK@ouk
8aHE=x/TL
下面给出一个webwork调用示例: [L-wAk:Fb
java代码: Kn$t_7AF^
?`Z:vqp>Z
{Pe&J2
+
/*Created on 2005-6-17*/ 7_3
PM
3C
package com.adt.action.user; 8>j&) @q
oMAUR
"
import java.util.List; 6@lZVM)E
VTR4uT-
import org.apache.commons.logging.Log; v(0ujfSR0
import org.apache.commons.logging.LogFactory; au19Q*r9
import org.flyware.util.page.Page; G[ns^
c/.s`hz
import com.adt.bo.Result; =#4>c8MM
import com.adt.service.UserService; %x,HQNRDU
import com.opensymphony.xwork.Action; 1O,5bi>t7
4E=QO!pVv
/** Chl^LEN:
* @author Joa dY.X/f
*/ eN5F@isy
publicclass ListUser implementsAction{ VWt=9D;
|g \_xl
privatestaticfinal Log logger = LogFactory.getLog \kV|S=~@
#l+Rs3T:
(ListUser.class); AW\uE[kg
2sgp$r
private UserService userService; #s(ob `0|
"D>/#cY1/
private Page page; &b,A-1`w_
dm"x?[2:
privateList users; f
uU"
r2tE!gMC
/* xc-[gt6
* (non-Javadoc) Qt\:A!'jw
* UxB3/!<5g3
* @see com.opensymphony.xwork.Action#execute() 9G6ZKqum
*/ ^PE|BCs
publicString execute()throwsException{ (bsywM
Result result = userService.listUser(page); yz,_\{}
page = result.getPage(); '`gnJX
JO
users = result.getContent(); ^-Arfm%dn
return SUCCESS; #a@ jt
} W,,3@:
0iC5,
/** 1,zc8 >M
* @return Returns the page. -#;ZZ\fdj
*/ L$"x*2[A
public Page getPage(){ % &H^UxC
return page; )mAD <y+
} JgHYuLB
6)=;cc{Vr
/** U7/
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* @return Returns the users. SJc*Rl>
*/ fUis_?!
publicList getUsers(){ =Gj~:|;$
return users; CUc ,
} RWu<
dY#ym
$L|+Z>x
/** .L^j:2(L
* @param page s!D?%
* The page to set. w(S&X"~
*/ `'r~3kP*NT
publicvoid setPage(Page page){ 1x/ R
this.page = page; Hsov0
} (6H7?nv
=],c$)
/** Z
s|*+[
* @param users (I;81h`1G
* The users to set. QCDica `+*
*/ *
#z@b
publicvoid setUsers(List users){ <
fe.
this.users = users; c>c4IQ&d
} txMC^-J2l
E.N>,N
/** s)3CosU
* @param userService o,_F;ZhE
* The userService to set. WFFd3TN%<
*/ pcOKC 0b.
publicvoid setUserService(UserService userService){ pE+:tMH;
this.userService = userService; H,EZ%
Gl
} afaQb
} UWqX}T[^
zmuRn4Nv
1S+T:n
:KRNLhWb
I_?R(V[9
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, dF! B5(
41.xi9V2
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 X?u=R)uG
xrNe:Aj
么只需要: &F;bg
java代码: n^55G>"0|
{fEb>
j~+(#|
<?xml version="1.0"?> [*C~BM
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork |z@AvS[
Y)(w&E>1
1.0//EN" "http://www.opensymphony.com/xwork/xwork- -!T24/l
nnu#rtvZp}
1.0.dtd"> 6&LmR75C
XdlA)0S)
<xwork> +#UawYLJ
[z_ztK1
<package name="user" extends="webwork- xu]Kt+QnSk
)"tM[~e`
interceptors"> 2}.~
6EU/
U? U3?Y-k`
<!-- The default interceptor stack name X
g7xy>{]
<?;KF2A({
--> PRyzvc~
<default-interceptor-ref !iX/Ni:
\|]+sQ WQ
name="myDefaultWebStack"/> :To{&T
z}r
<action name="listUser" z^/9YzA!6
5YI6$ZdQ
class="com.adt.action.user.ListUser"> L"T :#>
<param eAQ-r\h'2
#'i,'h+F
name="page.everyPage">10</param> ofYZ!-V
<result h y\iot
R:^jQ'1
name="success">/user/user_list.jsp</result> }U}ppq0Eo
</action> 0E3;f;'X
QQ=tiW
</package> w:1UwgcPC
JnQ@uZb`
</xwork> , a2=OV
"N,@J-]/k
?aB%h
|VA
}KftVnD?
SFEDR?s
(A?w|/bZd
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 0}:Wh&g
k0b6X5
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。 O
~[[JAi[
_3g!_
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 "-IF_Hid
7#N= GN
olHmRJ
7^#O{QYol
(\
|Go-2G
我写的一个用于分页的类,用了泛型了,hoho rof9Rxxe-
ME5M;bz(
java代码: egWfKL&iy
Kb/qM}jS
$(yi+v
package com.intokr.util; rNke&z:%X_
@!!5el {
import java.util.List; Smh=Q4,W
$p}q,f.
/** E;k$ICOXA
* 用于分页的类<br> }1a(*s,s-^
* 可以用于传递查询的结果也可以用于传送查询的参数<br> XZTH[#MqeI
* KfC{/J\
* @version 0.01 mZnsr@KF
* @author cheng >V%.=})K
*/ NXS$w{^
public class Paginator<E> { B" ]a8}u
privateint count = 0; // 总记录数 P+e {,~o
privateint p = 1; // 页编号 p7.~k1h
privateint num = 20; // 每页的记录数 pQ ul0]
privateList<E> results = null; // 结果 ,a0RI<D
fQw=z$
/** lm{4x~y$h
* 结果总数 VEL!-e^X&
*/ 3r?T|>|
publicint getCount(){ 3n_t^=
return count; ,RAP_I!_x
} a]8W32
w`/~y
publicvoid setCount(int count){ szOa yAS
this.count = count; g`6I, 6G
} .F\[AD 5
Iq{/-,v
/** Nk$|nn9#'
* 本结果所在的页码,从1开始 W=n
Hi\jLV
* {XnBj}C
* @return Returns the pageNo. <#./q LSR
*/ & TN.6Hm3
publicint getP(){ ,s,AkH
return p; [_C([o'\KY
} Ubwmn!~
w[^lxq
/** po*r14f
* if(p<=0) p=1 B+c,3@)x
* =,s5>2
* @param p 1l.HQ IS
*/ -(#`JT8
publicvoid setP(int p){ 0OtUb:8LX
if(p <= 0) c'bh`H4
p = 1; R0GD9
this.p = p; '^'PdB
} ?uF3Q)rCk
R@IwmJxX
/** c48I-{?
* 每页记录数量 D3+<16[,
*/ +}f}!h;
publicint getNum(){ M'NOM>8
return num; MiMDEe%f%
} ciCQe]fS
Xw162/:h
/** 8xoC9!xt
* if(num<1) num=1 4Ub7T=LG
*/ raR=k!3i
publicvoid setNum(int num){ 'SWK{t \4
if(num < 1) :?)q"hE
num = 1; H[?l)nZ}
this.num = num; anH ]]
} $A98h-*x
k+eeVy
/**
1<0Z@D~F
* 获得总页数 B2)5Z]
*/ <II>io;
publicint getPageNum(){ fV!~SX6S
return(count - 1) / num + 1; 7v`~;}5
} 4y,pzQ8a
U@}P]'`'f
/** `mS0]/AV/
* 获得本页的开始编号,为 (p-1)*num+1 7aHP;X~0
*/ #V@vz#bo=
publicint getStart(){ ?{OU%usQwE
return(p - 1) * num + 1; T>5N$i
} Et&PzDvU
Ol8Yf.e_
/** pO N@
* @return Returns the results. W;F=7[h
*/ J2!)%mF$
publicList<E> getResults(){ c
<X( S
return results; [3v&j_
} OXV9D:bIa
G~f|Sx
public void setResults(List<E> results){ 22E I`}"J
this.results = results; b C"rQJg
} k!g%vx
v;s^j
public String toString(){ C]krJse@
StringBuilder buff = new StringBuilder 6'.CW4L
e8)8QmB{o
(); u X(#+
buff.append("{");
&/)To
buff.append("count:").append(count); o4YF,c+>q
buff.append(",p:").append(p); ]QF*\2b-I2
buff.append(",nump:").append(num); VB=jKMi
buff.append(",results:").append 8y]{I^z}
Lv-M.
(results); ~W_T3@
buff.append("}"); Tqx
return buff.toString(); <,&t}7M/:
} 2bOFH6g
J>+~//C
} zHXb[$Q
v;Rm42k
A/~^4DR