Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 z(X6%p0
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Bt7v[Ot
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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 _%TeTNY#
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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 Y <k,E
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分页支持类: htrj3$q(4
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java代码: }Q^a.`h
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package com.javaeye.common.util; b e%*0lr
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import java.util.List; 6MNA.{Jdd
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publicclass PaginationSupport { V(uRKu
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publicfinalstaticint PAGESIZE = 30; ld?.o/
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privateint pageSize = PAGESIZE; BIf].RY
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privateList items; oz-I/g3go
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privateint totalCount; $QBUnLOek&
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privateint[] indexes = newint[0]; 1 ZFSz{
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privateint startIndex = 0; >!.9g
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public PaginationSupport(List items, int AK?j1Pk
*v/*_6f*
totalCount){ wT yM9wz&
setPageSize(PAGESIZE); {=7i}xY]T
setTotalCount(totalCount); mJR
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setItems(items); 3F!+c 8e
setStartIndex(0); yLOLv6g~e
} H5 hUY'O
Pp hQa!F$
public PaginationSupport(List items, int zRFM/IYC
++"PPbOe&D
totalCount, int startIndex){ S,RJ#.:F[t
setPageSize(PAGESIZE); ITlkw~'G
setTotalCount(totalCount); 9'h^59
setItems(items); w/6@R 4)p
setStartIndex(startIndex); S6tH!Z=(g
} IuW10}"9
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public PaginationSupport(List items, int TJ:Lz]l >
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totalCount, int pageSize, int startIndex){ #K w\r50
setPageSize(pageSize); mDfWR
setTotalCount(totalCount); 4HE4e
setItems(items); X-FHJ4
setStartIndex(startIndex); D/UGN+
}
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publicList getItems(){ ),,vu
return items; -1JHhRr]
} EPy/6-5b
Y&:i^k
publicvoid setItems(List items){ 4/>={4Y9
this.items = items; -m/4\D
} ;xwQzu%M>5
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publicint getPageSize(){ CV "Y40
return pageSize; --kK<9J7
} 6~>k]G
4PQWdPv;
publicvoid setPageSize(int pageSize){ `f]O
this.pageSize = pageSize; "g-NUl`'
} O]lfs>>x
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publicint getTotalCount(){ e_V(G
return totalCount; VIzZmd
} ]XU#i#;c
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publicvoid setTotalCount(int totalCount){ zhE7+``g
if(totalCount > 0){ 8t%1x|!
this.totalCount = totalCount; 7ow1=%Q
int count = totalCount / 4+Y5u4`t
fZ$2bI=
pageSize; =Frr#t!(w0
if(totalCount % pageSize > 0) M.xEiHz
count++; 46~ug5gV
indexes = newint[count]; S##W_OlrI
for(int i = 0; i < count; i++){ Gj 3/&'k6
indexes = pageSize * rej[G!
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i; WM26-nR
} u:ISwAp
}else{ 2+PIZ6=hN
this.totalCount = 0; 4<|u~n*JF
}
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} Za w+
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publicint[] getIndexes(){ u2QJDLMJv
return indexes; xh0!H|
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} K4BMa]/U
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publicvoid setIndexes(int[] indexes){ 0W> ",2|z
this.indexes = indexes; 'mF}+v^
} )1/O_N6C
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publicint getStartIndex(){ Vs
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return startIndex; 6k2~j j1d
} R)/w
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publicvoid setStartIndex(int startIndex){ i+}M#Y-O
if(totalCount <= 0) 6%TV X
this.startIndex = 0; r_G`#Z_5F
elseif(startIndex >= totalCount) 2;/hFwm
this.startIndex = indexes bTj,5,8i
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[indexes.length - 1]; ]P.S5s'
elseif(startIndex < 0) RW5T}
this.startIndex = 0; RaAq>B
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else{ qpZ".
this.startIndex = indexes -Db(
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[startIndex / pageSize]; zC7;Zj*k
} {PZe!EQ
} 5@Sb[za
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publicint getNextIndex(){ n}2}4^
int nextIndex = getStartIndex() + ]Sh&8 #
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pageSize; !|D,cs
if(nextIndex >= totalCount)
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return getStartIndex(); fI6F};I5}T
else QFMS]
return nextIndex; @_;6L
} .*ZNZ|g_
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publicint getPreviousIndex(){ d97wiE/i<
int previousIndex = getStartIndex() - l1@:&j3h
)[A}h'J)
pageSize; %lujme
if(previousIndex < 0) -Jb
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return0; bcQ$S;U)
else _$r+*nGDz
return previousIndex; Rcu/ @j{O
} FK->|
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} qu?D`29
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抽象业务类 x,n;GR
java代码: !O*\|7A(
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/** X4jtti
* Created on 2005-7-12 =h4XsV)rO
*/ dD=dPi#
package com.javaeye.common.business; xand%XNv
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import java.io.Serializable; 9T)-|fja_
import java.util.List; ondF
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import org.hibernate.Criteria; t'^/}=c-
import org.hibernate.HibernateException; Y}PI{PN
import org.hibernate.Session; YI|7a#*F
import org.hibernate.criterion.DetachedCriteria; )nQ.6
import org.hibernate.criterion.Projections; =^NR(:SaaU
import ;asB@Q
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org.springframework.orm.hibernate3.HibernateCallback; _Y=>^K]9K
import k<m{Wp;-
JBp^@j{_
org.springframework.orm.hibernate3.support.HibernateDaoS IG
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upport; Ue!
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import com.javaeye.common.util.PaginationSupport; =}F &jl
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public abstract class AbstractManager extends Fe}Dnv)}Z
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HibernateDaoSupport { }Dm-Ibdg(
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privateboolean cacheQueries = false; PE0A `
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privateString queryCacheRegion; VD,g
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publicvoid setCacheQueries(boolean J;HkR9<C
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cacheQueries){ V0XQG}
this.cacheQueries = cacheQueries; O$+0 .
} hvkLcpE
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publicvoid setQueryCacheRegion(String QOB>TvE
> X<pzD3u
queryCacheRegion){ q{ i9VJ]
this.queryCacheRegion = R_`i=>Z-
vWc =^tT
queryCacheRegion; F|Pf-.r`t
} kZfa8wL]P
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publicvoid save(finalObject entity){ v'mRch)d
getHibernateTemplate().save(entity); %We~k'2f
} UiO%y
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publicvoid persist(finalObject entity){ (R5n ND
getHibernateTemplate().save(entity); g1UP/hNJ\8
} jvv3;lWDL.
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publicvoid update(finalObject entity){ |uf{:U)
getHibernateTemplate().update(entity);
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} $dIu${lu
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publicvoid delete(finalObject entity){ K Rs
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getHibernateTemplate().delete(entity); I?r7dQEm
} l];w,(u{
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publicObject load(finalClass entity, o."k7fLB
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finalSerializable id){ dNK Q&TC
return getHibernateTemplate().load : .Y
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(entity, id); n@>h"(@i
} sxc^n
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publicObject get(finalClass entity, B /q/6Pp
jd ]$U_U(
finalSerializable id){ vMG >Xb
return getHibernateTemplate().get Z1Y/2MVSb
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(entity, id); NX.%Rj*
} xgeDfpF'
g2)jd[GM
publicList findAll(finalClass entity){ gJ;jh7e@
return getHibernateTemplate().find("from k%2woHSu&
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" + entity.getName()); F9h'.{@d
} !'m
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publicList findByNamedQuery(finalString N!me:|Dn
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namedQuery){ /1D]\k()
return getHibernateTemplate ,yPs4',d
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().findByNamedQuery(namedQuery); %*:X
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} B"; >zF
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publicList findByNamedQuery(finalString query, "&9L
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finalObject parameter){ 4S9hz
return getHibernateTemplate CB!5>k+mC
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Q'
().findByNamedQuery(query, parameter); v$n J$M&k
} ]\TYVv)
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publicList findByNamedQuery(finalString query, _.}1 Y,Q
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finalObject[] parameters){ '>"riEk
return getHibernateTemplate lRO7 Ae
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().findByNamedQuery(query, parameters); J~jxmh
} S2APqRg*
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publicList find(finalString query){ C4,;l^?=%
return getHibernateTemplate().find D6Q6yNE
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(query); pYxdE|2j
} E`A6GX
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publicList find(finalString query, finalObject ?@@BIg-
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parameter){ }Cs.Hm0P
return getHibernateTemplate().find #.j[iN
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(query, parameter); }piDg(D
} DTx!# [
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public PaginationSupport findPageByCriteria jsp)e=
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(final DetachedCriteria detachedCriteria){ &x
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return findPageByCriteria \h{M\bSIEa
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Id(wY$C&>
} Bu{1^g:
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public PaginationSupport findPageByCriteria G+k~k/D 6
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(final DetachedCriteria detachedCriteria, finalint asj*/eC$/i
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startIndex){ `i"7; _HoV
return findPageByCriteria $~G=Hcl9
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(detachedCriteria, PaginationSupport.PAGESIZE, _+0QQ{'N
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startIndex); ,Oj
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} Vi:<W0:
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public PaginationSupport findPageByCriteria .29y3}[PO
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(final DetachedCriteria detachedCriteria, finalint }i\U,mH0_&
$%GW~|S\C
pageSize, WF&?OHf2
finalint startIndex){ QE\t}>
return(PaginationSupport) q33Z.3R
t Urwg
getHibernateTemplate().execute(new HibernateCallback(){ Pkq?tm$#
publicObject doInHibernate I5$]{:L|9
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(Session session)throws HibernateException { =)O%5<Lwx
Criteria criteria = ? 3'O
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detachedCriteria.getExecutableCriteria(session); M~SbIk<#a<
int totalCount = 4r+s"
|
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((Integer) criteria.setProjection(Projections.rowCount muZ6 }&4
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()).uniqueResult()).intValue(); (imaL,M-D
criteria.setProjection A])+Pe
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(null);
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List items = gd=gc<z YP
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criteria.setFirstResult(startIndex).setMaxResults rd\:.
.kT}E5
(pageSize).list(); G Ch]5\
PaginationSupport ps = VAL]\@Q}
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new PaginationSupport(items, totalCount, pageSize, M7x*LiKc2
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startIndex); NAnccB D!{
return ps; @5tW*:s
} 'G>gNq
}, true); grWmF3c#
} $sa5aUg }
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public List findAllByCriteria(final ("!P_Q#
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DetachedCriteria detachedCriteria){ {<J(*K*\Jo
return(List) getHibernateTemplate |tVWmm^m
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().execute(new HibernateCallback(){ W}0cM9 g
publicObject doInHibernate `rQDX<?
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(Session session)throws HibernateException { iFBH;O_~
Criteria criteria = >v9@p7Dn
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detachedCriteria.getExecutableCriteria(session); 9s9_a4t5
return criteria.list(); M>m+VsJV
} P"k`h=>!4
}, true); "gQA|NHwV
} M"l<::z
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public int getCountByCriteria(final PS\n0
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DetachedCriteria detachedCriteria){ ;mtv
Integer count = (Integer) 'v?"TZ
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getHibernateTemplate().execute(new HibernateCallback(){ [/'=M h
publicObject doInHibernate l<"Z?z
)Co&(;zf
(Session session)throws HibernateException { 3^x
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Criteria criteria = ?x-:JME0
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detachedCriteria.getExecutableCriteria(session); '3'*VcL(
return g*a|QBj%
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criteria.setProjection(Projections.rowCount
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aAP
()).uniqueResult(); j 5{"j
} 3g''j7
}, true); s>+,u7EV
return count.intValue(); ]%I}hjJ
} aH(B}wh{
} ^}\!Sn
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用户在web层构造查询条件detachedCriteria,和可选的 *!p#1fE
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 JS{trqc1d
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PaginationSupport的实例ps。 /ltGSl
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ps.getItems()得到已分页好的结果集 ;E0aTV)Zp
ps.getIndexes()得到分页索引的数组 %V2A}78
ps.getTotalCount()得到总结果数 4,.B#: 8
ps.getStartIndex()当前分页索引 )e6)~3[^
ps.getNextIndex()下一页索引 8IrA{UU
ps.getPreviousIndex()上一页索引 s+RSAyU
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 jXCSD@?]K
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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 gdKn!; ,w#
u:[vqlU
一下代码重构了。 U`w `Cr
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我把原本我的做法也提供出来供大家讨论吧: dnXre*rhz
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首先,为了实现分页查询,我封装了一个Page类: Fu;\t 0
java代码: {@tqeu%IM
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/*Created on 2005-4-14*/ %D9,Femt
package org.flyware.util.page; 'L1=:g.\i
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/** 0! 6n
* @author Joa piv/QP-X
* l]wjH5mz=i
*/ 5&QDZnsl
publicclass Page { V% PeZ.Xv
&R7N^*He
/** imply if the page has previous page */ %hnv
go:^g
privateboolean hasPrePage; S>y(3E]I
zVL"$ )
/** imply if the page has next page */ vy&< O
privateboolean hasNextPage; J/ !Mt
h'D-e5i
/** the number of every page */ G,]%dZHe
privateint everyPage; J#OiY
WhY8#B'?
/** the total page number */ wAn}ic".b
privateint totalPage; _pM~v>~*+
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Wu
/** the number of current page */ BEfp3|Stb
privateint currentPage; 9f+S-!
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/** the begin index of the records by the current RXZ}aX[h
Ny
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query */ ;uK">L[u'
privateint beginIndex; _U%fD|t
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/** The default constructor */ H7=[sL^
public Page(){ qDzd_E@aR
3$E\B=7/U
} bF#1'W&
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/** construct the page by everyPage 1`;,_>8
* @param everyPage NE'4atQ|
* */ K/OE;;<IA
public Page(int everyPage){ `z?6.+C
this.everyPage = everyPage; fQtV-\Bc
} 5*#!w1X
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/** The whole constructor */ Fo0dz
public Page(boolean hasPrePage, boolean hasNextPage, nKP[U=ac
= @UgCu>=
l-GQ AI8
int everyPage, int totalPage, JkiMrpkuk
int currentPage, int beginIndex){ pP`KI'aUN
this.hasPrePage = hasPrePage; n%"0%A
this.hasNextPage = hasNextPage; HRPNZ!B
this.everyPage = everyPage; E(l'\q'.
this.totalPage = totalPage; :W++`f&
this.currentPage = currentPage; 6N^sUc0s
this.beginIndex = beginIndex; c,\!<4
} Ki"o0u
_ zh>q4M
/** ATdK)gG
* @return l_Ffbs_6t
* Returns the beginIndex.
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*/ &$!'Cw`,
publicint getBeginIndex(){ "gR W91
T
return beginIndex; >*5+{~k~4
} )7H s
ns{BU->f
/** v@6TC 1M,
* @param beginIndex @L)=epC
* The beginIndex to set. UX9r_U5)
*/ ^YpA@`n
publicvoid setBeginIndex(int beginIndex){ :tv:46+s=
this.beginIndex = beginIndex; k>N >_{\
} J:{$\m'
TvEN0RV2
/** 6__#n`
* @return %/86}DCfE?
* Returns the currentPage. S;582H9D
*/ |Bv?!
sjf
publicint getCurrentPage(){ Or0eY#c
return currentPage; e@-"B9~
} D~;hIt*
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/** 3E!#?N|v
* @param currentPage ^Ms)T3dM
* The currentPage to set. B" -gK20vY
*/ rb/m;8v>
publicvoid setCurrentPage(int currentPage){ <By6%<JTn
this.currentPage = currentPage; o4)^U t+
} SX{shM2
)-_NtMr~`!
/** PgKA>50a
* @return FN#6pM']|
* Returns the everyPage. 5aF03+ko
*/ f PoC
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publicint getEveryPage(){ YHVJg?H3
return everyPage; iK*2 Z$`lw
} Su<Ggv"
^lqcF.
/** kAbkhZ1^
* @param everyPage +\`D1d@
* The everyPage to set. _)J;PbK~
*/ -fl?G%:(!0
publicvoid setEveryPage(int everyPage){ OIF0X!
this.everyPage = everyPage; TzXivE@mm
}
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/** {gE19J3
* @return uzO%+B!
* Returns the hasNextPage. /t-m/&>
*/ SR9Cl
publicboolean getHasNextPage(){ 8oSndfV
return hasNextPage; UTEUVcJ\
} U!:Q|':=h
[)}F4Jsz%
/** ."R,j|o6
* @param hasNextPage Zho d %n3
* The hasNextPage to set. ]Dm'J%P0}
*/ r\y~
:
publicvoid setHasNextPage(boolean hasNextPage){ XEF|B--,
this.hasNextPage = hasNextPage; m*L*# ZBS
} P8K{K:T
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/** T}(J`{9i
* @return ]X,C9
* Returns the hasPrePage. QN_Zd@K*A
*/ p=U*4[9k
publicboolean getHasPrePage(){ }&d@6m]
return hasPrePage; +'abAST
t
} nDnSVrvd-i
JcEPwF.
/** t\nYUL-H
* @param hasPrePage ?5e:w?&g@
* The hasPrePage to set. 3^l@!Qw
*/ xzg81sV7
publicvoid setHasPrePage(boolean hasPrePage){ .g.v
this.hasPrePage = hasPrePage; n?*Fr sZ
} WJ$D]7
$LLkYOwI
/** ~6`HJ
* @return Returns the totalPage. F}P+3IaE
* ahNpHTPa
*/ h#9X0u7j
publicint getTotalPage(){ Q=lQ y
return totalPage; EnXNTat})
} rvZXK<@#+
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/** x@3Ix,b'
* @param totalPage PSz|I8
c
* The totalPage to set. (]0JI1
d
*/ MXsSF|-
publicvoid setTotalPage(int totalPage){ |Id0+-V
?
this.totalPage = totalPage; X>^St&B}fC
} L.XGD|m
M<oIo036
} _|`~CLE[
Lu!o!>b
wP.b2X_V
9|v3lGK(
Jylav:
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 6qQdTp{i
<U(wLG'XS
个PageUtil,负责对Page对象进行构造: (055>D6
java代码: VWqmqR%
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/*Created on 2005-4-14*/ {/SUfXq
package org.flyware.util.page; Mz,G;x}
@&(0]kZ6
import org.apache.commons.logging.Log;
bK:mt `
import org.apache.commons.logging.LogFactory; ?-w<H!Y7
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/** *;7~aM
* @author Joa I;xrw?=\L
* X6I"&yct
*/ D?ojxHe
publicclass PageUtil { k I
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privatestaticfinal Log logger = LogFactory.getLog M?m Pi 3
C;]}Ht:~I
(PageUtil.class); /U\k<\1~m
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/** ~n9x
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* Use the origin page to create a new page BZHba8c(
* @param page 4eOS+&
* @param totalRecords BN??3F8C
* @return 8$)xxV_zp
*/ <r 2$k"*:
publicstatic Page createPage(Page page, int ~jcdnm]
VZhtx)
totalRecords){ 6! `^}4
return createPage(page.getEveryPage(), Eod'Esye5
j{ QzD^t
page.getCurrentPage(), totalRecords); r"HQ>Wn
} QX`Qnk|Y
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/** cg`bbZ
* the basic page utils not including exception 3vdhoS|
~)ut"4
handler FYe#x]ue
* @param everyPage \PU7,*2
* @param currentPage )>-94xx|
* @param totalRecords +UvT;"
* @return page rnNB!T
*/ ::<v; `l
publicstatic Page createPage(int everyPage, int &Ul8h,qw
/i:c!l9
currentPage, int totalRecords){ $W_sIS0\z
everyPage = getEveryPage(everyPage); /O`<?aP%
currentPage = getCurrentPage(currentPage); P]h-**O
int beginIndex = getBeginIndex(everyPage, mCb1^Y
<rQ+ErDA
currentPage); qnO>F^itF
int totalPage = getTotalPage(everyPage, W=-:<3XL
rl/]Ym4j
totalRecords); 58]C``u@Y
boolean hasNextPage = hasNextPage(currentPage, C3k[ipCN
k[ZkVwx
totalPage); *'l|ws
boolean hasPrePage = hasPrePage(currentPage); "A9qC*6[
0(o{V:l%Z|
returnnew Page(hasPrePage, hasNextPage, nNc>nB1
everyPage, totalPage, eVRPjVzQ'Q
currentPage, Y'&rSHI"
P >>VBh?
beginIndex); ?"@`SEdnU2
} GS)4,.
zm~sq_=^
privatestaticint getEveryPage(int everyPage){ F-TDS<[S?
return everyPage == 0 ? 10 : everyPage; G4<M@ET
} BbCaIt
^.gBHZ
privatestaticint getCurrentPage(int currentPage){ ,v@C=4'm
return currentPage == 0 ? 1 : currentPage; /:GeXDJw
} (8Inf_59
N+nv#]{
privatestaticint getBeginIndex(int everyPage, int jCK 0+,;
VKb=)v[K
currentPage){ B;Dl2k^L
return(currentPage - 1) * everyPage; :k/Z|
} XF Cwa
bAwFC2jO[
privatestaticint getTotalPage(int everyPage, int (dnaT-M3
E``\Jre@
totalRecords){ ]!'}{[1}
int totalPage = 0; qBDhCE
@Wl2E.)K;
if(totalRecords % everyPage == 0) 4?',E ddo
totalPage = totalRecords / everyPage; _t-e.2a
v
else 6` 4,
totalPage = totalRecords / everyPage + 1 ; g^)8a;/c
XGcl9FaO}
return totalPage; aB ^`3J
} 60XTdJkDkA
dw YGhhm
privatestaticboolean hasPrePage(int currentPage){ 79d<,q;uR
return currentPage == 1 ? false : true; []<N@a6VA>
} <tI_u ~P
qBF}-N_
privatestaticboolean hasNextPage(int currentPage, &]S\GnqlU]
5J2tR6u-(
int totalPage){ HLb`'TC3r+
return currentPage == totalPage || totalPage == |y DaFv
#McX
0 ? false : true; 20`QA
u)'
} COFCa&m9c
8T"8C
Z" N}f
,
} PM8*/4Cu.5
7*(K%e"U
58[.]f~0
cNG`-+U'
%ou@Y`
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 ,r,$x4*
I!u fw\[
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 #<81`%
Co^GsUJ
做法如下: @WnW
@'*F
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 I.{%e;Reg
V!zU4!@qP
的信息,和一个结果集List: qK,PuD7i"
java代码: DgGG*OXY
R=<uf:ca
~mk>9Gp
/*Created on 2005-6-13*/ ^-g-]?q
package com.adt.bo; 5K {{o''
UO}Yr8Z;
import java.util.List; *DuP~8
;6tGRh$b
import org.flyware.util.page.Page; I`S?2i2H
nRh.;G
/** )|`w;F>
* @author Joa cjc1iciZ
*/ ~vw$Rnotz
publicclass Result { pg/SYEvsV
2<TpNGXM_
private Page page; IZ&FNOSZ+4
p#>d1R1&
private List content;
EzGO/uZ]
#iAw/a0&
/** 4N_iHe5U
* The default constructor
RFT`r
*/ bI+ TFOP
public Result(){ ;C~:C^Q\H
super(); *9|*21
} 3?uah'D5
L
/V;;
/** OHK]=DH:M
* The constructor using fields /m8&E*+T1
* >m4HCs>
* @param page f#|
wb~
* @param content O[\obi"}
*/ I@l }%L
public Result(Page page, List content){ {:ZsUnzm
this.page = page; 3AcCa>
this.content = content; `l}+BI`4
} C$7dmGjZ
QO <.l`F
/** p[:E$#W~;
* @return Returns the content. :i/uRR
*/ mE"},ksg
publicList getContent(){ BiD}C
return content; OG{vap)
} n--w-1
,xuA%CF-S
/** Or"+d 5
* @return Returns the page. ZGC*BP/
*/ @{o3NR_
public Page getPage(){ N2\{h(*u
return page; Ztj~Q 9mu
} T56%3i
TY]-L1$
/** `xie/
* @param content ??h4qJ
* The content to set. g<jgR*TE`
*/ Bb@m-+f
public void setContent(List content){ (cdtUE8
this.content = content; 8 CCA}lOG
} "t:9jU
)~ =g}&
/** ;}QM#5Xdt
* @param page } DQ KfS
* The page to set. UwVc!Lys
*/ *$v`5rP
publicvoid setPage(Page page){ 7)
this.page = page; ]97`=,OUg
} XS`=8FQ
} 6;%Ajx
!1fAW!8
Olltu"u
*|^}=ioj*
1^^9'/
2. 编写业务逻辑接口,并实现它(UserManager, XpoEZ|0
@zAav>
UserManagerImpl) oV=~Q#v
java代码: ~2 M+Me
y-k]Tr
Q|i`s=|
/*Created on 2005-7-15*/ U[WR?J4~LX
package com.adt.service; K
f}h{X
>TB Rp,;r
import net.sf.hibernate.HibernateException; T<S_C$O
ZDt|g^
import org.flyware.util.page.Page;
M;zJ1
Hsvu&>[`S
import com.adt.bo.Result; ;1Zz-@
{j4J(dtO
/** =b[q<p\
* @author Joa rIo)'L$uU
*/ z57|9$h}w
publicinterface UserManager { ra>jVE0`
#Ss lH
public Result listUser(Page page)throws
~N=$%C
@-H D9h
HibernateException; <[w>Mbqj_
2nA/{W\ hC
} #Y;tobB
fqQ(EVpQ
~
$QNp#dq
`6B jNV
H6/C7
java代码: A@qwD300Vo
mb_~
"}A
1 wB2:o<
/*Created on 2005-7-15*/ \V/;i.ng
package com.adt.service.impl; cs6I
K6wo
DP<[Uz&
import java.util.List; 'awZ-$#
Z%1{B*(e
import net.sf.hibernate.HibernateException; -/z #?J\
d-BUdIz
import org.flyware.util.page.Page; t9(sSl
import org.flyware.util.page.PageUtil; oNK-^N?-T
nW7Ew<`Q
import com.adt.bo.Result; 3I%F,-r
import com.adt.dao.UserDAO; c"x-_Uk
import com.adt.exception.ObjectNotFoundException; qp)a`'Pq
import com.adt.service.UserManager; 2,.;Mdl
JC}oc M
j0
/** -|aNHZr
* @author Joa p?qW;1
*/ pXBlTZf
publicclass UserManagerImpl implements UserManager { r"aJ&~8::W
Lkl+f~m
private UserDAO userDAO; ((T0zQ7=
ZB@Bj>,bp
/** [>y 0Xf9^
* @param userDAO The userDAO to set. \yNe5
*/ oGa8#>
publicvoid setUserDAO(UserDAO userDAO){ 1`z^Xk8vt
this.userDAO = userDAO; C^W9=OH
} =n73bm
8R;A5o,
/* (non-Javadoc) dOfEEqPI
* @see com.adt.service.UserManager#listUser ?O!'ZZX
zJ7=r#b
(org.flyware.util.page.Page) 5Dv;-G;
*/ 3duWk sERC
public Result listUser(Page page)throws e6JT|>9A7
_J+p[=[L
HibernateException, ObjectNotFoundException { %e,X7W`'2
int totalRecords = userDAO.getUserCount(); mx:) &1
if(totalRecords == 0) 5l
ioL)
throw new ObjectNotFoundException *6b$l.Vs
WUnmUW[/
("userNotExist"); Jfs$VGZP;
page = PageUtil.createPage(page, totalRecords); 9=wt9` ?
List users = userDAO.getUserByPage(page); %/r}_V(UN
returnnew Result(page, users); Y::I_6[eV
} vn0}l6n3s
$Z8=QlG>
} |&hu3-(
(&y~\t]H
!0+!%Nr>J
f6d:5
X_
zld[uhc>
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Hve'Z,X
W@(EEMhw
询,接下来编写UserDAO的代码: Vs0T*4C=n
3. UserDAO 和 UserDAOImpl:
hb_J.Q
java代码: B]xZ
4Y
k Up[b~
cJ>
#jl&
/*Created on 2005-7-15*/ Cb5Rr+K=
package com.adt.dao; viP.G/(\]
G?t<4MTv
import java.util.List; snW=9b)m
H]XY
import org.flyware.util.page.Page; M-Tjp'=*
Q{~ WWv
import net.sf.hibernate.HibernateException; v[O }~E7'
9Un3La8PX
/** `qnNEJL,
* @author Joa ? V0!N;
*/ eA$wJ$*
publicinterface UserDAO extends BaseDAO { }eO{+{D+
yX'f"*
publicList getUserByName(String name)throws #nv =x&g
TI9]v(
HibernateException; 1JFCYJy
ZB5:FtW4
publicint getUserCount()throws HibernateException; 5ZX P$.
gC+PpY#2h
publicList getUserByPage(Page page)throws v%=@_`Ht
/g_cz&luR
HibernateException; 5a PPq~%
c8^M::NI
} m4<5jC`-M
ds*N1[
*
);]9M~$
W@vt6v
ID#p5`3n
java代码: gyt[ZN_2
h
"MiD
;!ICLkc$
/*Created on 2005-7-15*/ 7H+IW4Ma
package com.adt.dao.impl; vH^6O:V
gB;5&;T:
import java.util.List; -8r';zR
jc4#k+sb
import org.flyware.util.page.Page; c,K)*HB
h2b,(
import net.sf.hibernate.HibernateException; cL]vJ`?Ih
import net.sf.hibernate.Query; 8R) 0|v&;
=Ts3O0"[
import com.adt.dao.UserDAO; hLqRF4>L
V+A9.KoI
/** !>,\KxnM
* @author Joa iB]xYfQ&@V
*/ t==CdCl
public class UserDAOImpl extends BaseDAOHibernateImpl X3bPBv
\ r^#a
implements UserDAO { Cj,Yy
&!xePKvO6k
/* (non-Javadoc) \-]zXKl2k
* @see com.adt.dao.UserDAO#getUserByName b-d{)-G{(
4P406,T]r
(java.lang.String) H'Oy._,]t
*/ {CO]wqEj
publicList getUserByName(String name)throws B#|c$s{
K-a~Kr
HibernateException { #{m~=1%;Ya
String querySentence = "FROM user in class nOH x^(
qM$4c7'4P6
com.adt.po.User WHERE user.name=:name"; m#i5}uHHg
Query query = getSession().createQuery 3>~W_c9@
wX!q dII)
(querySentence); ~yGD("X
query.setParameter("name", name); QGR}`n2D
return query.list(); 2@A%;f0Q
} \W,,@-
(R9{wGV [
/* (non-Javadoc) i-<1M|f
* @see com.adt.dao.UserDAO#getUserCount() XY_zFF
*/ i7%v2_
publicint getUserCount()throws HibernateException { JB
<GV-l
int count = 0; 1(q&(p
String querySentence = "SELECT count(*) FROM U
'$W$()p
Q{:5gh
user in class com.adt.po.User"; FQ3{~05T
Query query = getSession().createQuery <Lt%[dn
"CX@a"
(querySentence); At0ahy+
count = ((Integer)query.iterate().next BidTrO
F3%8E<QZd;
()).intValue(); ~YH'&L.O
return count; Mur)'
} d
:a*;F
H;~Lv;,g,
/* (non-Javadoc) Bp7`W:?#"
* @see com.adt.dao.UserDAO#getUserByPage (/^s?`1{N?
+=V[7^K;
(org.flyware.util.page.Page) v<_wf
*/ Hdn%r<+c
publicList getUserByPage(Page page)throws jQ"z\}Wf
wDv G5
HibernateException { \Fs+H,S<
String querySentence = "FROM user in class j@Ta\a-,x
gfW_S&&q
com.adt.po.User"; ^5GyW`a}
Query query = getSession().createQuery zUIh^hbFf
1^HmM"DD
(querySentence); 4ZX6=-u^
query.setFirstResult(page.getBeginIndex()) ,(@J Ntx
.setMaxResults(page.getEveryPage()); \Zgc
[F
return query.list(); :kU-ol$
} $!ATj`}kb
C9FzTg/c
} - _KO}_
2LTMt?
PsMp&~^
:f/T$fa*
#$^vP/"$
至此,一个完整的分页程序完成。前台的只需要调用 okkMx"
0# d:<+4D
userManager.listUser(page)即可得到一个Page对象和结果集对象 eJvNUBDSH
m+a\NXWR?N
的综合体,而传入的参数page对象则可以由前台传入,如果用 Wp
|qv
TpH-_ft
webwork,甚至可以直接在配置文件中指定。 !!\x]$v
^aONuG9
下面给出一个webwork调用示例: hRFm]q
java代码: k0(_0o
{@7xOOAw
I)AbH<G{
/*Created on 2005-6-17*/ DfsPg':z
package com.adt.action.user; ;]PP+h
^D5+S`V
import java.util.List; QUO'{;,
'~\\:37+
import org.apache.commons.logging.Log; gy*c$[NS$
import org.apache.commons.logging.LogFactory; ,vh$G 7D
import org.flyware.util.page.Page; Gv+$7{
B4MrrW4=
import com.adt.bo.Result; Q^{XM
import com.adt.service.UserService; 2CY4nSKW
import com.opensymphony.xwork.Action; Errs6
%Ek!3t
/** [q!/YL3%
* @author Joa W'Y?X]xr
*/ L']"I^(N
publicclass ListUser implementsAction{ {bP
)Fon
nXT/zfS
privatestaticfinal Log logger = LogFactory.getLog mFgrT
pdySip<
(ListUser.class); m|]:oT`M
EGysA{o"X
private UserService userService; QF4)@ r{2x
^iqy|zNtn
private Page page; Xx+eGV";`
gA:unsI
privateList users; 5rH?FQE
<;lwvO
/* r]=Z :
* (non-Javadoc) cw/E?0MWb
* ;Qi0j<dXd
* @see com.opensymphony.xwork.Action#execute() {l9g YA
*/ H{4_,2h=m
publicString execute()throwsException{ 8.zYa(<2
Result result = userService.listUser(page); MS`XhFPS.
page = result.getPage(); dlRTxb^Y>u
users = result.getContent(); W
P9PX
return SUCCESS; O~#A )d6
} VVw5)O1'
>+9:31p
/** T"/dn%21
* @return Returns the page. c+upoM
*/ {_R{gpj'
public Page getPage(){ D!V~g72j
return page; m Eg3.|
} OK(xG3T
J-z<&9
/** -
VdCj%r>
* @return Returns the users. 5VSc5*[
*/ S.; ahce
publicList getUsers(){ |pZ:5ta#
return users; @:}l a
} B:VGa<lx5
X#o<))
/** H6hhU'Kxf8
* @param page a$3 ]`
* The page to set. aZ8f>t1Q
*/ wUfm)Q#
publicvoid setPage(Page page){ G2&,R{L6w
this.page = page; jN!VrRA
} i3cMRcS;
|$Cfm}
/** uNca@xl'
* @param users Myf2"\}
* The users to set. <tW/9}@p9
*/ YIF|8b\
publicvoid setUsers(List users){ T^ - - :1
this.users = users; &\
K
} +LlAGg]Z
]GDjR'[z
/** c`/kx
* @param userService Z&n#*rQ7[
* The userService to set. m95]
z18T'
*/ H`,t "I
publicvoid setUserService(UserService userService){ jW{bP_,"
this.userService = userService; <B'PB"R3y
} 0./Rdf=-1j
} lQv(5hIm
`Ue5;<K-/
PbfgWGr
cUO$IR)yL
jhkXU+4
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, y,K> Wb9e
iu$Y0.H@
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$ps
(w vU;u
么只需要: {"*_++|
java代码: 4>/i,_&K K
7eW6$$ju,N
ZiRCiQ/?
<?xml version="1.0"?> Zy|u5J
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 0U !&|i\
:(4q\~
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 4O:HT m
9v1 Snr
1.0.dtd"> !3{.
V\P)
ge1U1o
<xwork> E= .clA
ENI|e,'[
<package name="user" extends="webwork- $j\jT
N4b{^JkF
interceptors"> D&pp
<
deJ/3\t
<!-- The default interceptor stack name Hz=s)6$ey
x3F94+<n{
--> SwaMpNXL
<default-interceptor-ref VV sE]7P ]
93ggCOaYA
name="myDefaultWebStack"/> ;9q$eK%d
@H^\PH?pp
<action name="listUser" Wys$#pJ
@!|h!p;
class="com.adt.action.user.ListUser"> c`N_MP
<param L0w2qF
#B
q|^:nj
name="page.everyPage">10</param> Vt-V'`Y
<result Q.\vN-(
,b?G]WQrHs
name="success">/user/user_list.jsp</result> )\kNufP
</action> ,Ek6X)|@
=LEzcq>XO
</package> C%j@s|
?}S!8;d
</xwork> 8#9OSupp
|tz{Es<`B
<p +7,aE_
Mc,p]{<<AV
Xn5LrLM&
2wgcVQ
Awa
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 Zu>CR_C
9>ZX@1]m_
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 $$*0bRfd4=
G^SDB!/@J
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 uC6e2py<[
E.-2 /'i
~H"-km"@
;=@?( n
=#wE*6T9
我写的一个用于分页的类,用了泛型了,hoho '*t<g@2$
I*mBU^<9V
java代码: 9WHarv2 @
y5Fgf3P@ju
<l>L8{-3
package com.intokr.util; 6)FM83zk)K
E~8J<gE
import java.util.List; #vViEBVeN
zE7)4!
/** GkKoc v
* 用于分页的类<br> e'=#G$S?g
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 5RY rAzQo
* -Byl~n3*D
* @version 0.01 h(^[WSa
* @author cheng "L9pFz</
*/ -cUw}
public class Paginator<E> { 9'KOc5@l^
privateint count = 0; // 总记录数 B<~BX[
privateint p = 1; // 页编号 eEeK ]8@
privateint num = 20; // 每页的记录数 h9~oS/%:
privateList<E> results = null; // 结果 '%a:L^a?
nzU0=w}V
/** ^HHT>K-m
* 结果总数 wqyF"^It"
*/ W=,]#Z+M;
publicint getCount(){ gpCWXz')i
return count; )1O|+m k
} *4l6+#W
3p'(E\VJ
publicvoid setCount(int count){ $tK/3
this.count = count; jLEO-<)-)
} #O7phjzgD
4c.!^EiV
/** d2g7,axi
* 本结果所在的页码,从1开始 5[^Rf'wy
* Nm3CeU
* @return Returns the pageNo. xB}B1H%
*/ h6D1uM"o
publicint getP(){ % "ZC9uq?
return p; f^[m~
} Gk|T1%
IN"6=2:
/** Jz-RMX=
* if(p<=0) p=1 "}uV=y
* )N&95\u
* @param p 3[%n@i4H|
*/ ")W5`9
publicvoid setP(int p){ #?bOAWAwLh
if(p <= 0) ]yas]5H
p = 1; XZ|\|(6Cc
this.p = p; kX:8sbZ##4
} =AeOkie
}`uq:y
/** . 3xf!E*
* 每页记录数量 s18A
*/ (z%OK[
publicint getNum(){ JiiYl
return num; ^]$rh.7&
} S2$r 6T
szy2"~hm
/** _(KzjOMt
* if(num<1) num=1 \}7xgQ>oV
*/ p1,.f&(f
publicvoid setNum(int num){ g"D:zK)
if(num < 1) DXfQy6k'
num = 1; ;-kg3fGB1Q
this.num = num; 2%j"E{J&
} m>'#664q1
}M9I]\
/**
BU%gXr4Ra
* 获得总页数 +<c(;Ucl?
*/ UFr5'T
publicint getPageNum(){ R%;dt<Dh
return(count - 1) / num + 1; v$R7"
} Z]^O=kX7k
6am<V]Hw0F
/** 8' +I8J0l
* 获得本页的开始编号,为 (p-1)*num+1 '6Yx03t
*/ Rhh.fV3
publicint getStart(){ {7 nz:f
return(p - 1) * num + 1; Qx77%L4
} 2QV|NQSl
}zHG]k,j
/** =2, iNn
* @return Returns the results. H`8}w{ft&
*/ 6?3\P>`3Y
publicList<E> getResults(){ s C?-L
return results; w0fFm"A|W
} stlkt>9
e>$E67h<~
public void setResults(List<E> results){ 6ieP` bct
this.results = results; uJL[m(G
} }<G#bh6;Q
(/Dr=D{ `
public String toString(){ 0%]F&|
StringBuilder buff = new StringBuilder %ZJ;>a#
lNqF@eCT9
(); =BBDh`$R
buff.append("{"); ~_"/\;1
buff.append("count:").append(count); ~Z
x_"
buff.append(",p:").append(p); ^es/xt
buff.append(",nump:").append(num); 3 3b 3v\N
buff.append(",results:").append A \~tr
5KwT(R o
(results); mdukl!_x
buff.append("}"); :HDU\|{^
return buff.toString(); K1^x+I7%U[
} Y`
tB5P
Y'2 |GJc2
} h$q=NTV
L:RMZp*bK
5<L+T