Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 9\y\{DHd
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 }&!fT\4
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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 f-$%Ck$%,
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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 4E:kDl* @
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分页支持类: JlaT
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java代码: ^I! u H1G
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package com.javaeye.common.util; q}x+#[Ef
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import java.util.List; _e4%<!1
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publicclass PaginationSupport { xQA6!j
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publicfinalstaticint PAGESIZE = 30; NRIp@PIF:"
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privateint pageSize = PAGESIZE; U?/C>g%/PI
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privateList items; pA?kv]l(
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privateint totalCount; (?y (0%q
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privateint[] indexes = newint[0]; xQU$E|I
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privateint startIndex = 0; A*x3O%zH
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public PaginationSupport(List items, int S:F8`Gh
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totalCount){ I
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setPageSize(PAGESIZE); `514HgR
setTotalCount(totalCount); aWg*f*2f
setItems(items); .G/>X%X
setStartIndex(0); Thc"QIk&4
} Gq)E,Ln&d
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public PaginationSupport(List items, int CT2L }5L&
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totalCount, int startIndex){ e09('SON(
setPageSize(PAGESIZE); oj$^87KX
setTotalCount(totalCount); EEI!pi
setItems(items); x )w6
setStartIndex(startIndex); 4). i4]%LH
} 4+1aW BJ2
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public PaginationSupport(List items, int 5`tMHgQO
qPH=2k,H
totalCount, int pageSize, int startIndex){ ]ucz8('
setPageSize(pageSize); XLq%nVBM8\
setTotalCount(totalCount); oY(q(W0ze
setItems(items); Z]^Ooy[pb
setStartIndex(startIndex); Et0[HotO
} n97pxD_74
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publicList getItems(){ :Sc"fG,g)
return items; Ho!dtEs
} \2U F J
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publicvoid setItems(List items){ A8jj]J+
this.items = items; [$iKx6\
} c7~>uNgJ
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publicint getPageSize(){ CtO;_;eD'
return pageSize; 4n5r<?rY
} 7FBaN7l
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publicvoid setPageSize(int pageSize){ ,e93I6
this.pageSize = pageSize; Tj3xK%K_r3
} S#[w).7
T=~D>2C
publicint getTotalCount(){ yd+.hg&J
return totalCount; xZc].l6
} yzH[~O7
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publicvoid setTotalCount(int totalCount){ Jb1L[sT2
if(totalCount > 0){ IizPu4|
this.totalCount = totalCount; H5J1j*P<d
int count = totalCount / -+)06BqF}
9Z!|oDP-
pageSize; BSd\Sg4
if(totalCount % pageSize > 0) o1^Rx5
count++; +`]AutNv
indexes = newint[count]; %Ix
for(int i = 0; i < count; i++){ kH|cB!?x
indexes = pageSize * o-7,P
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i; cy{ ado2
} ^0T DaZDLp
}else{ 57~/QEdy
this.totalCount = 0; i[7<l&K]
} W9M~2<
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} -:~"c@D
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publicint[] getIndexes(){ Yk @/+PE
return indexes; -?}Z0e(w
} `-)Hot)
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publicvoid setIndexes(int[] indexes){ nd3n 'b
this.indexes = indexes; Q xm:5P
} /_{B_2i/>
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publicint getStartIndex(){ 5SQqE@g%
return startIndex; Ef2i#BoZ
} t4[<N
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publicvoid setStartIndex(int startIndex){ ==]BrhZK
if(totalCount <= 0) JZ>E<U9&
this.startIndex = 0; 5!jU i9
elseif(startIndex >= totalCount) 5h7M3s
this.startIndex = indexes hRaX!QcG3
]X\p\n'@j
[indexes.length - 1]; ({!S!k
elseif(startIndex < 0) -POsbb>
this.startIndex = 0; `x:8m?q05
else{ 0qp Pz|h
this.startIndex = indexes ~pWV[oUD
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[startIndex / pageSize]; {({Rb$
}
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} F\Q X=n
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publicint getNextIndex(){ |y.^F3PE
int nextIndex = getStartIndex() + H63?Erh>a
*&O4b3R
pageSize; \PL0-.t,
if(nextIndex >= totalCount) Qr9@e Q1Pp
return getStartIndex(); YMr2Dv\y
else %}[/lIxaE
return nextIndex; )uRR!<"~
} |YcYWok
e#!,/pE
publicint getPreviousIndex(){ B1 Y
int previousIndex = getStartIndex() - j^6,V\;l
5H}d\=z
pageSize; y"Ios:v@-
if(previousIndex < 0) n=A}X4^
return0; k< $(
else WGA"e
return previousIndex; vn1*D-?
} qlm7eS"sy
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} 7-("ppYX=
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抽象业务类 nj=nSD
java代码: }iRRf_
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/** lS |:4U.
* Created on 2005-7-12 Z> <,t~o}
*/ Cig!3
package com.javaeye.common.business; K`8$+JDP+
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import java.io.Serializable; mk[<=k~
import java.util.List; C )BVsHT4
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import org.hibernate.Criteria; C]M{
import org.hibernate.HibernateException; ~}g)N
import org.hibernate.Session; s)}EMDY
import org.hibernate.criterion.DetachedCriteria; 17[vq!x6
import org.hibernate.criterion.Projections; Bxk2P<d
import "O<TNSbrC
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org.springframework.orm.hibernate3.HibernateCallback; 7-MyiCt
import @vPGkM#oW
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org.springframework.orm.hibernate3.support.HibernateDaoS Ns6CxE9
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upport; mhMRY9 ahB
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import com.javaeye.common.util.PaginationSupport; O6]X\Cwj%
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public abstract class AbstractManager extends Kgb<uXk
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HibernateDaoSupport { [-h=L
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# N'_~:H
privateboolean cacheQueries = false; +?+iVLr!l}
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privateString queryCacheRegion; jN{+$ @cI
9`G}GU]@}
publicvoid setCacheQueries(boolean tNYCyw{K
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cacheQueries){ ?}<Wmy2A
this.cacheQueries = cacheQueries; 2fG[q3`
} \<x{U3q5
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publicvoid setQueryCacheRegion(String XT\Q"=FD
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queryCacheRegion){ C[nacAi
this.queryCacheRegion = g42f*~l
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queryCacheRegion; dgW/5g
} R![1\Yv&
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publicvoid save(finalObject entity){ g BV66L
getHibernateTemplate().save(entity); jT:kk
} 9FmX^t$T
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publicvoid persist(finalObject entity){ D]hwG0Chd
getHibernateTemplate().save(entity); Fr]B]Hj
} "U
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publicvoid update(finalObject entity){ S3&lkN5
getHibernateTemplate().update(entity); i`EG80\[Z
} qm|T<zsDY#
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publicvoid delete(finalObject entity){ ,Cj` 0v#
getHibernateTemplate().delete(entity); 8% `Jf`
} H(ds
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publicObject load(finalClass entity, OM#eJ,MH<)
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finalSerializable id){ ZqJyuTPv
return getHibernateTemplate().load h|XLL|:
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(entity, id); U$AV"F&!&}
} *)um^O
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publicObject get(finalClass entity, .eG_>2'1
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finalSerializable id){ Fq#;
return getHibernateTemplate().get %$}*y
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(entity, id); nZ~J&QK-
} {igVuZ(>en
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publicList findAll(finalClass entity){ $+p4X# _
return getHibernateTemplate().find("from ?;?$\b=
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" + entity.getName()); \EOPlyf8x
} GN@(!V#/4
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publicList findByNamedQuery(finalString ^V;2v? O
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namedQuery){ rT{+ h}vO
return getHibernateTemplate ?s5hckhh
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().findByNamedQuery(namedQuery); I,wgu:}P#
} J:JkX>n%k=
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publicList findByNamedQuery(finalString query, ^Yu%JCN8g
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finalObject parameter){ pv){R;f
return getHibernateTemplate Q
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().findByNamedQuery(query, parameter); D_)n\(3
} nK;c@!~pS
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publicList findByNamedQuery(finalString query, |*-&x:p7O
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finalObject[] parameters){ V [KFZSA
return getHibernateTemplate mq*Efb)!
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().findByNamedQuery(query, parameters); y7WO:X&
} =TG[isC/F9
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publicList find(finalString query){ 1T@#gE["Ic
return getHibernateTemplate().find szW85{<+
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(query); 8s#2Zv
} {e'V^l.v
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publicList find(finalString query, finalObject ;u
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parameter){ Uc<j{U
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return getHibernateTemplate().find k1)=xv#S
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(query, parameter); 7C"&f *lEi
} !w}cKm
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public PaginationSupport findPageByCriteria U#=5HzE
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(final DetachedCriteria detachedCriteria){ 0k\BE\PQk
return findPageByCriteria N|53|H
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); "Gh5
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} c. ;}e:)s
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public PaginationSupport findPageByCriteria *8?0vkZZ2
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(final DetachedCriteria detachedCriteria, finalint /$NZj"#
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startIndex){ qe{:9
return findPageByCriteria |}Wm,J
./#F,^F2
(detachedCriteria, PaginationSupport.PAGESIZE, "g=g' W#
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startIndex); e0; KmQjG
} SZ'2/#R>
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public PaginationSupport findPageByCriteria \2Atm,#4
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(final DetachedCriteria detachedCriteria, finalint ?f\ ~:Gm/
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pageSize, F&= X/
finalint startIndex){ ;:5Ahfo \
return(PaginationSupport) O h{>xg
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getHibernateTemplate().execute(new HibernateCallback(){ VQ,;~^Td
publicObject doInHibernate 8n1<nS<
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(Session session)throws HibernateException { DN%b!K:
Criteria criteria = pni*#W*n
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detachedCriteria.getExecutableCriteria(session); S7Tc9"oqV
int totalCount = @P@j9yR
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((Integer) criteria.setProjection(Projections.rowCount v3q.,I_
nS5g!GYY,k
()).uniqueResult()).intValue(); b|KlWt'
criteria.setProjection f0d*%
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(null); p|f5w"QcH
List items = )=]u]7p}
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criteria.setFirstResult(startIndex).setMaxResults &}q;,"
6*uWRjt
(pageSize).list(); e"@Ag:r@a
PaginationSupport ps = Un.u{$po
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new PaginationSupport(items, totalCount, pageSize, V9dJNt'Ui
41Nm+$m
startIndex); zD z"Dn9
return ps; ;?K>dWf3f
} }S,KUH.
}, true); 2QN ~E
} "1iLfQ
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public List findAllByCriteria(final ^0fe:ac;
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DetachedCriteria detachedCriteria){ RP1sQ6$
return(List) getHibernateTemplate [42EqVR
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().execute(new HibernateCallback(){ r-aCa/4y!
publicObject doInHibernate $(=0J*ND"
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(Session session)throws HibernateException { EK=PY
Criteria criteria = 7q;wj~
Q]7}"B&
detachedCriteria.getExecutableCriteria(session); L55VS:'
return criteria.list(); S+*g
} px>g
}, true); #x|IEjoa
} 7~2c"WE
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public int getCountByCriteria(final ~qu}<u)P
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DetachedCriteria detachedCriteria){ ;T,`m^@zf
Integer count = (Integer) A/A;'9
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getHibernateTemplate().execute(new HibernateCallback(){ T_NN.Ol
publicObject doInHibernate qvN`46c
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(Session session)throws HibernateException { Hph$Z1{
Criteria criteria = k0^t$J
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detachedCriteria.getExecutableCriteria(session); +F@ZVMp
return aP}30E*Y
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criteria.setProjection(Projections.rowCount Y0Bd[
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()).uniqueResult(); k,0lA#>
} L_{gM`UFc
}, true); e]k\dj;,^%
return count.intValue(); ,E3Ze*(U
} ^EFVjGM
} fB"It~ p
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用户在web层构造查询条件detachedCriteria,和可选的 mVVL[z2+
sOb=+u$$9
startIndex,调用业务bean的相应findByCriteria方法,返回一个 m(rd\3d
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PaginationSupport的实例ps。 R^+,D
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ps.getItems()得到已分页好的结果集 \yKYBfp-p
ps.getIndexes()得到分页索引的数组 >m'n#=yap
ps.getTotalCount()得到总结果数 jx[g;7~X
ps.getStartIndex()当前分页索引 ,/Usyb,`
ps.getNextIndex()下一页索引 m!LJK`gA
ps.getPreviousIndex()上一页索引 Zv^n
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Q=n2frW(T
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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 K1_#Jhz
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一下代码重构了。 gBd@4{y6C.
W0;MGBfb
我把原本我的做法也提供出来供大家讨论吧: (_Ky'.
1!p7N$QR
首先,为了实现分页查询,我封装了一个Page类: 4KnrQ-D
java代码: JS#AoPWA
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/*Created on 2005-4-14*/ 'd |*n#Dqc
package org.flyware.util.page;
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/** cZl/8?dj}
* @author Joa <BX'Owbs!O
* G-Dc(QhU&
*/ Q1^kU0M }
publicclass Page { kH" >(f
4ZCD@C
/** imply if the page has previous page */ *EllE+M{n
privateboolean hasPrePage; AZf$XHP2
hzV= 7
/** imply if the page has next page */ @;`d\lQ
privateboolean hasNextPage; `g^b Qx
H-/w8_} KG
/** the number of every page */ D V=xqC6}
privateint everyPage; G'0JK+=o
!.@F,wZvY
/** the total page number */ i(an]%'v
privateint totalPage; Cd'`rs}3
v!6IH
/** the number of current page */ ?AYb@&%
privateint currentPage; qLa6c2o,
Yc2dq e>
/** the begin index of the records by the current ]CGH )4Pe
':#DROe!
query */ -W.bOr
privateint beginIndex; 6S&OE k
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/** The default constructor */ 0;Z] vl/|
public Page(){ fX{Xw0
SmCtwcB1
} x9 i^_3Z
o@uZU4MM
/** construct the page by everyPage Kdr}7#c
* @param everyPage \fSo9$
* */ /0(c-Dv
public Page(int everyPage){ NEW0dF&)
this.everyPage = everyPage;
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} *^i"q\n5(
+Y"HbNz
/** The whole constructor */ I/)*pzt8
public Page(boolean hasPrePage, boolean hasNextPage, RW|Xh8.O
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8 c5=Px2\
int everyPage, int totalPage, V@pUU~6R
int currentPage, int beginIndex){ Y{g[LG`U
this.hasPrePage = hasPrePage; $/"QYSF
this.hasNextPage = hasNextPage; C"R}_C|r)*
this.everyPage = everyPage; EqF>=5*
this.totalPage = totalPage; uxbLoE
this.currentPage = currentPage; *QA{xvT
this.beginIndex = beginIndex; 9\!=i
} oq[r+E-]$@
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/** x{9$4d
* @return =F/ EzS
* Returns the beginIndex. tu6<>
*/ Kj/Lcx;bh
publicint getBeginIndex(){ b]g#mQ
return beginIndex; ~WKWx.ul
} 1^tM%2rP'
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/** UL]zuW/
* @param beginIndex BMItHn].
* The beginIndex to set. ?G 'sb}.
*/ *3rp
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publicvoid setBeginIndex(int beginIndex){ iHeu<3O
this.beginIndex = beginIndex; A@jBn6
} -q&7q
H^<?h6T
/** uoTc c|Kc
* @return X3HJ3F;==
* Returns the currentPage. /Nns3oE
*/ |}Mt hj9n
publicint getCurrentPage(){ N5 mhs#
return currentPage; 8@r>`c
} P5__[aTD
)!=fy']
/** 6W9lKD_i
* @param currentPage \ESNfL5
* The currentPage to set. C:z7R" yj
*/ )i[K1$x2
publicvoid setCurrentPage(int currentPage){ p~OX1RBI
this.currentPage = currentPage; f('##pND@
} pV*d"~T
#g~]2x
/** DI[
* @return g ,yB^^%
* Returns the everyPage. 1rV9dM#F
*/ I5E+=.T*ar
publicint getEveryPage(){ ekd;sEO
return everyPage; h<i.Z7F;tj
} /w2NO9Q
uTrQ<|}#
/** \zzPsnFIg
* @param everyPage @B9#Hrc
* The everyPage to set. dTqL[?wH?
*/ jF-0 fK;)*
publicvoid setEveryPage(int everyPage){ (I;lE*>
this.everyPage = everyPage; kfq<M7y
} F6"Qs FG
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/** 0oo_m6ie&
* @return RQ,X0pS
* Returns the hasNextPage. M1I4Ot
*/ LG'1^W{a
publicboolean getHasNextPage(){ 1~vv<`-
return hasNextPage; B RtT 7
}
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Tvw(Sq};
/** Oyp)Wm;@
* @param hasNextPage >Sm#-4B-
* The hasNextPage to set. Pz-=Eq
*/ M] W5%3do
publicvoid setHasNextPage(boolean hasNextPage){ `3.bux~
this.hasNextPage = hasNextPage; P7!gUxcv9Y
} Nrc-@ ]
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/** :KsBJ>2ck
* @return n;k
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* Returns the hasPrePage. kv`5"pa7M
*/ uN6xOq/
publicboolean getHasPrePage(){ M B,Z4 ^
return hasPrePage; aWb5w
} h|ja67VG
_? u} Jy_
/** j4h?"
* @param hasPrePage 6H:EBj54?
* The hasPrePage to set. sJ|IW0Mr
*/ > u=nGeO
publicvoid setHasPrePage(boolean hasPrePage){ QM'>)!8
this.hasPrePage = hasPrePage; T7Yg^ -"
} Do;rY\sY
2^&5D,}0
/** OoR0>!x Z
* @return Returns the totalPage. ~T&X#i
* \>4x7mF!
*/ 5fK<DkB$>:
publicint getTotalPage(){ 6d YUMqQ
return totalPage; qFjnuQ,w
} \K(#
r=
x[2eA!NC
/** )>a^%V9
* @param totalPage YCNpJGM
* The totalPage to set. BU;E6s>P
*/ 6Q9S~YYq
publicvoid setTotalPage(int totalPage){ +IfU
5&5<
this.totalPage = totalPage; DKqO5e\l8@
} xsXf_gGu
r$-]NYPi
} sTO9>~sj
Q?W}]RW
q=cH ^`<.
WhR'MkfL
Le}-F{~`^
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 -j"2rIl4#
kM/;R)3t4/
个PageUtil,负责对Page对象进行构造: Fv9n>%W&
java代码: {siIRl2&
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/*Created on 2005-4-14*/ yn-TN_/Y,
package org.flyware.util.page; @60/IE{-v
f}F
import org.apache.commons.logging.Log; qct:xviH<|
import org.apache.commons.logging.LogFactory; %q
7gl;'
$qj||zA
/** bO?Us
* @author Joa j#E&u*IR
* {H%1sI
*/ -dsE9)&8DX
publicclass PageUtil { | WMq&-$D
%QrpFE5V5
privatestaticfinal Log logger = LogFactory.getLog \ )n'Ywr
@^kt[$X;
(PageUtil.class); U49
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Vy[ m%sEP
/** x(/{]$h
* Use the origin page to create a new page [boB4>.
* @param page ,,[pc
* @param totalRecords >
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* @return IQ"9#{o
*/ *(sFr E
publicstatic Page createPage(Page page, int vtVc^j4
APBe76'3)
totalRecords){ )w++cC4/5
return createPage(page.getEveryPage(), J 4OgV?
*
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page.getCurrentPage(), totalRecords); c*#*8R9.y
} Xi!`+N4
KcQe1mT!+
/** #$[}JiuL/
* the basic page utils not including exception O}IRM|r"
78W&
handler o|BEY3|
* @param everyPage @(mXiK
* @param currentPage {g(-C&
* @param totalRecords k)l^;x-
* @return page evBr{oi@
*/ ZBAtRs
publicstatic Page createPage(int everyPage, int l@zr1g)
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currentPage, int totalRecords){ hqKftk)+
everyPage = getEveryPage(everyPage); b\O%gg\p%!
currentPage = getCurrentPage(currentPage); u`2[V4=L
int beginIndex = getBeginIndex(everyPage, 7pY7iR_
r g$2)z1
currentPage); w_hGWpm
int totalPage = getTotalPage(everyPage, ;{k`nv_6
aA-gl9
totalRecords); _v9P0W^.7
boolean hasNextPage = hasNextPage(currentPage, |NZVm}T
\tWFz(
totalPage); oHbG-p
boolean hasPrePage = hasPrePage(currentPage); #K3`$^0 s
Cd"iaiTD0
returnnew Page(hasPrePage, hasNextPage, *uq}jlD`!
everyPage, totalPage, RvPC7,vh
currentPage, I;<aJo6Yl
D^5bzZk
N
beginIndex); UpU2H4
} LPNJuz
C;6Nu W
privatestaticint getEveryPage(int everyPage){ C&QT-|
return everyPage == 0 ? 10 : everyPage; $C;) Tlh
} Oa'DVfw2J
l?N|Gj;ZFZ
privatestaticint getCurrentPage(int currentPage){ 9y~5@/32R
return currentPage == 0 ? 1 : currentPage; !Deg!f\g
} MyyNYZ
; SS/bS|
privatestaticint getBeginIndex(int everyPage, int n8.W$ &-ia
O7_u9lz2
currentPage){ : ;nvqb d
return(currentPage - 1) * everyPage; &z@~n
} VR @V3 ~
B3lP#ckh
privatestaticint getTotalPage(int everyPage, int H40~i=.
fU )@Lj1Wo
totalRecords){ g.3a5#t
int totalPage = 0; .FarKW
|Mj2lZS
if(totalRecords % everyPage == 0) |(Bc0sgw}
totalPage = totalRecords / everyPage; BJ0P1vh6M
else ` n*e8T
totalPage = totalRecords / everyPage + 1 ; c /G4@D>
_%xe:X+ M
return totalPage; KkIxtFM
} ,co~@a@9
]Cfjs33H
privatestaticboolean hasPrePage(int currentPage){ <}@*i
return currentPage == 1 ? false : true; dOm@cs
} )<?^~"h
s+@+<QE
privatestaticboolean hasNextPage(int currentPage, Md4hd#z
:6
, `M,
int totalPage){ pf\
Ybbs
return currentPage == totalPage || totalPage == ,eI2#6w|C
A)2eo<ij4
0 ? false : true; ^/0c`JG!x
} ^ZxT0oaL
4=G)j+RCH
D#=$? {w
} <sALA~p|0
9hJlc
S,ENbP%0r
~o_zV'^f@o
{Dc{e5K
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 tJ"8"T#6Vr
F9Hxqa#1T
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 6.!aJJLN
p;y\%i_
做法如下: #~_ZG% u
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 n=z=%T6
I"=a:q
的信息,和一个结果集List: wWVLwp4-
java代码: oMb&a0-7u
?~%Go
lU`}
/*Created on 2005-6-13*/ W~!uSrY
package com.adt.bo; W
Ai91K@
[Yq*DkW
import java.util.List; >FR;Ux~a
T{USzMj
import org.flyware.util.page.Page; 0qCx.<"p8#
e5s=@-[
/** 5DI&pR1eZ
* @author Joa 8l50@c4UF~
*/ 1ti9FQ
publicclass Result { R5,ISD
+s
nNEIwlj;
private Page page; z#( `H6n:
apkmb<
private List content; [ r<0[
f4[Bj{F
/** X!AD]sK
* The default constructor vNA~EV02
*/ -~|E(ys
public Result(){ Ih;I&D+e;
super(); <5xlP:Cx
} KE_GC ;bQ
UNC%<=
/** `J26Y"]P
* The constructor using fields 0sR+@\
* 8%,u~ELA
* @param page 2Sha&Z*CE
* @param content =iFI@2
*/ 1M<;}hJ{/
public Result(Page page, List content){ ?kBX:(g
this.page = page; b-"kclK
this.content = content; ,QZNH?Cp/
} }R\;htmc;
*@-a{T}
/** b;~?a#Z}
* @return Returns the content. .}4^b\
*/ i\yp(tE%^
publicList getContent(){ 7A6: *
return content; bPL.8hX
} _enS_R
G,,7.%eib=
/** UVlXDebl
* @return Returns the page. 7FYq6wi
*/ [izP1A$r#Q
public Page getPage(){ q Xj]O3
mm
return page; *vS)aRK
} 8_h:_7e
G>?'b
/** v9K=\ j
* @param content .Z#8,<+
* The content to set. |k[hk
*/ 4Mr)~f rc
public void setContent(List content){ '6zk>rN
this.content = content; 3zsjL=ta
} MWHzrqCA
hI}rW^o^
/** ll#_v^
* @param page KpF/g[m
* The page to set. hG! |ts
*/ Zf*DC~E_
publicvoid setPage(Page page){ Hr}pO"%
this.page = page; +T*]!9%<`:
} qV&ai {G:
} &l;wb.%ijW
J=7<dEm&
*If]f0?%
,Z aPY
hutdw>
2. 编写业务逻辑接口,并实现它(UserManager, |*te69RX
_a&Mk
UserManagerImpl) 9Lp[y%{GP
java代码: c8}jO=/5+
?<h|Q~JH
.~jn
N
/*Created on 2005-7-15*/ +~l`rJ
package com.adt.service; iD`>Bt7gD
Ua\<oD79]
import net.sf.hibernate.HibernateException; oaMh5FPy
O od?ifA
import org.flyware.util.page.Page; (rB?@:zN
`bMwt?[*
import com.adt.bo.Result; jdW#;
]7+y
%o4HCzId<
/** !dZpV~g0
* @author Joa @$]
CC1Y
*/ r>.^4Z@
publicinterface UserManager { fNNik7
4M3{P
public Result listUser(Page page)throws X0+M|8:
ns;nle|m
HibernateException; q A?j-H
[X=J]e^D
} * u{CnH
w/Ej>OS
n=tg{_9f%
MsLQ'9%Au
W
y%'<f
java代码: 1 6G/'Hb
9<Kc9Z
lL]8~3b
/*Created on 2005-7-15*/ &bw
``e&c
package com.adt.service.impl; 9G)q U
`|d&ta[{
import java.util.List; ?>
SH`\
o:C],G_
import net.sf.hibernate.HibernateException; DX)T}V&mP
Z2soy-
import org.flyware.util.page.Page; 7\p<k/TS
import org.flyware.util.page.PageUtil; +'f38D*
'@
C\ ,E
import com.adt.bo.Result; pGh A
import com.adt.dao.UserDAO; 3t^r;b
import com.adt.exception.ObjectNotFoundException; L?~-<k
import com.adt.service.UserManager; Kl)PF),
gt=
_;KZ
/** fsVQZ$h73
* @author Joa ^7O,Vk"Z
*/ G: p!PB>=
publicclass UserManagerImpl implements UserManager { ' *x?8-K P
FMBzTD
private UserDAO userDAO; ~IP3~m D
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/** <+2M,fq+
* @param userDAO The userDAO to set. "Ca?liy
*/ 2 -
?
publicvoid setUserDAO(UserDAO userDAO){ *q/oS8vavd
this.userDAO = userDAO;
DU.nXwl]
} h=Xr J
kH10z~(e
/* (non-Javadoc) A! j4;=}
* @see com.adt.service.UserManager#listUser <u9U%Vsi
%}%vey
(org.flyware.util.page.Page) d,0Yi
u.p
*/ r\sQ8/
public Result listUser(Page page)throws k2S6 SB
MX.=k>
HibernateException, ObjectNotFoundException { ?[K\X
int totalRecords = userDAO.getUserCount(); USrg,A
if(totalRecords == 0) >kJEa8
throw new ObjectNotFoundException h
r!Htew4
_'lrI23I
("userNotExist"); Tfba3+V
page = PageUtil.createPage(page, totalRecords); s]p3dB#
List users = userDAO.getUserByPage(page); B{0m0-l
returnnew Result(page, users); RO1xcCp
} 9G'Q3?
z
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} "77 j(Vs9
`1$7. ydQ
aH1mW;,1u
4LBMhLy
c%+9uu3
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 :"aCl~cy9g
YLfZ;W|6u
询,接下来编写UserDAO的代码: f9Hm2wV
3. UserDAO 和 UserDAOImpl: @pKQ}?
java代码: 5$|wW}SA
}FTyRHD|
`Al5(0Q
/*Created on 2005-7-15*/ ^dzg'6M
package com.adt.dao; K8l|qe
U_UX *
import java.util.List; W&U
Nk,
=N9a!ii|
import org.flyware.util.page.Page; K]
^kUN_
W]UGo,
import net.sf.hibernate.HibernateException; 6J|Y+Y$
4D`T_l
/** fdD?"z
* @author Joa U0+Hk+
*/ C>qKKLZ
publicinterface UserDAO extends BaseDAO { +##b}?S%
$Qv+*%c
publicList getUserByName(String name)throws ~8-Z=-
[kyF |3k~
HibernateException; CjtXU=}A
/8GgEW9Q~G
publicint getUserCount()throws HibernateException; IR+dGqIjZb
>!OD[9
publicList getUserByPage(Page page)throws >HUU`= SC
\I@=EF- &
HibernateException; 5Z 7 <X2
T>&d/$;]
} wnL\.%Y^
_d'x6$Jg
24)3^1P\V
D! 1oYr
E0<9NFQr7
java代码: _M/ckv1q@
D-/K'|b
6BihZ|H04
/*Created on 2005-7-15*/ X;7gh>Q'4
package com.adt.dao.impl; &cSTem
0
4dXuy>Km
import java.util.List; 2z7+@!w/
Wb] ha1$
import org.flyware.util.page.Page; DAG2pc8zA
?=B$-)/
import net.sf.hibernate.HibernateException; M%dXy^e
import net.sf.hibernate.Query; JRkC~fv
b<de)MG
import com.adt.dao.UserDAO; ?q(7avS9
BpL,<r,
/** t%e}'?#^
* @author Joa 2<Tbd"x?
*/ coHzbD~#H
public class UserDAOImpl extends BaseDAOHibernateImpl )v-sde\
+-=w`
implements UserDAO { +zQ
a"Ep*
X ?/C9
/* (non-Javadoc) h&+dIk\[3
* @see com.adt.dao.UserDAO#getUserByName Ji_3*(
3[E3]]OVa
(java.lang.String) bu[v[U4
*/ kzG mDi
publicList getUserByName(String name)throws {$,e@nn
:A\8#]3
HibernateException { ~a:0Q{>a
String querySentence = "FROM user in class 8.
[TPiUn'
A@BYd'}]
com.adt.po.User WHERE user.name=:name"; )oJn@82C|
Query query = getSession().createQuery L'LZK
$9DV}
(querySentence); sv0)sL
query.setParameter("name", name); wR\Y+Z
return query.list(); wRn]
} [];*9vxW
ab!,)^
/* (non-Javadoc) ?GPTJ#=j=]
* @see com.adt.dao.UserDAO#getUserCount() CpuL[|51
*/ t<M^ /xe2
publicint getUserCount()throws HibernateException { V,<3uQD9a
int count = 0; #1i&!et&/
String querySentence = "SELECT count(*) FROM EELS-qA
,y}?Z8?63
user in class com.adt.po.User"; 7q<2k_3<
Query query = getSession().createQuery tCAh?nR
6eqxwj{S[
(querySentence); <(dHh9$~
count = ((Integer)query.iterate().next }>I|\Z0I
Z,%^BAJ
()).intValue(); Hn5:*;N
return count; ]a)o@FI
} 7F OG^
oa(R,{_*q
/* (non-Javadoc) nqNL[w6{
* @see com.adt.dao.UserDAO#getUserByPage *HFRG)[V
q~68)D(
(org.flyware.util.page.Page) #Hl0>"k
,
*/ =&RpW7]
publicList getUserByPage(Page page)throws ;*^2,_
+G';no\h
HibernateException {
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String querySentence = "FROM user in class W 86`R
Tf/jd 3>
com.adt.po.User"; &<}vs`W
Query query = getSession().createQuery F+mn d,3
hI.@!$~=
(querySentence); kLa9'c0
query.setFirstResult(page.getBeginIndex()) T
22tZp
.setMaxResults(page.getEveryPage()); FES_:?.0
return query.list(); v#1}(
hb
} h+)XLs
TbqH-R3W
} ^'j? {@
]n9o=^q/
A)9OkLrc
o!W
71
ol QT r
至此,一个完整的分页程序完成。前台的只需要调用 6%bZZTP`
w&yK*nBK
userManager.listUser(page)即可得到一个Page对象和结果集对象 c5x2FM z
1p&e:v
的综合体,而传入的参数page对象则可以由前台传入,如果用 ]hNio6CVm
(}ObX!,
webwork,甚至可以直接在配置文件中指定。 Y5nj _xQJL
~NT2QY5!K
下面给出一个webwork调用示例: eT33&:n4
java代码: )Qe<XJH!
77D>;90>?
jFbj)!;
/*Created on 2005-6-17*/ h3-y}.VjG
package com.adt.action.user; Bx9R!u5D
Ws%@SK
import java.util.List; :.8@ xVH
Dv~W!T i
import org.apache.commons.logging.Log; 0LEJnl
import org.apache.commons.logging.LogFactory; 84g$V}mp
import org.flyware.util.page.Page; \)KLm
RCM;k;@8V
import com.adt.bo.Result; WzD=Ol
import com.adt.service.UserService; 1iNq|~
import com.opensymphony.xwork.Action; Vwxb6,}Z
P2la/jN
/** bMe/jQuL.$
* @author Joa &QHZ]2%U
*/ gR7in!8
publicclass ListUser implementsAction{ D%[yAr;r
mX8k4$z
privatestaticfinal Log logger = LogFactory.getLog .[mI9dc
?8AV-rRX
(ListUser.class); v@m2c_,
vmEbk/Vy
private UserService userService; fXNl27c-
BwpEIV@b]
private Page page;
zciL'9
d$DNiJ ,
privateList users; jQ>~
$K& #R-
/* 1eod;^AP9
* (non-Javadoc) XT2:XWI8
* Fpe>|"&
* @see com.opensymphony.xwork.Action#execute() qPal'c0
*/ d\c?sYLv
publicString execute()throwsException{ 3|++2Z{},
Result result = userService.listUser(page); |E]`rfr
page = result.getPage(); 73C7g<
Mx
users = result.getContent(); M N-j$-y}
return SUCCESS; Sq<ds}o'8l
} ;og[q
olA 1,8
/** m2sf]-?Y
* @return Returns the page. ^@91BY
*/ Hs9; &C
public Page getPage(){ 'xK ,|U
return page; E4}MU}C#[
} prypo.RI
oItEGJ|
/** "W71#n+[
* @return Returns the users. _;zIH5 H
*/ Z [[AmxE'l
publicList getUsers(){ r<)>k.]
!
return users; ][D/=-
} V^S` d8?
G q&[T:
/** )t?_3'W
* @param page w'i8yl
bZ
* The page to set. {OIktG2gZ
*/ {tKi8O^Rb
publicvoid setPage(Page page){ %[l#S*)~
this.page = page; :,8eM{.Q
} E]MyP=g$
xZ\`f-zL
/** w?JRY
* @param users xZE%Gf_U
* The users to set. $!LL
*/ Uo]x6j<
publicvoid setUsers(List users){
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this.users = users; "|,;~k1
} ,$oz1,Q/
A?zxF5rfp
/** =NNA7E7c
* @param userService XYrZI/R
* The userService to set. |'+ [ '
*/ $ca>bX]
publicvoid setUserService(UserService userService){ Id}@
this.userService = userService; 6+.8nx:9X
} Jf</83RZ
} j&y>?Y&Sb
wJ>.I<F6B
^J-"8%
PSB@yV <
=@\Li)Y
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, nqv#?>Z^OT
e0e3b]
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 CqAv^n7 }
O!3`^_.
么只需要: >|W\8dTQ
java代码: .ng:Z7
$`'%1;y@
Ld4Jp`Zg
<?xml version="1.0"?> b%_[\((
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork +Rq7m]
"k>;K,:
1.0//EN" "http://www.opensymphony.com/xwork/xwork- X/AA8QV o
vVfIe5+OP
1.0.dtd"> -.
J@
_/pdZM,V
<xwork> %YLyh?J
u.!<)VIJx
<package name="user" extends="webwork- 8]2j*e0xV
^`f( Pg!
interceptors"> wK*b2r}0/
0(h'ZV
<!-- The default interceptor stack name -;s-*$I
^2<nn op
--> R![)B97^
<default-interceptor-ref {)y8Y9G
];U}'&
name="myDefaultWebStack"/> mA" 82"
JANP_b:t
<action name="listUser" XJ*W7HD
:ySQ[AJ"
class="com.adt.action.user.ListUser"> F7N4qq1
<param -guVl4 V
Z5[f
name="page.everyPage">10</param> %:=Jr#a
<result S!{Kn ;@
tLc~]G*\`s
name="success">/user/user_list.jsp</result> 2nv-/%]
</action> #Py\'
Ynx.$$`$=
</package> iTpK:pX
s]@k,%
</xwork> <uL0M`u3
R)u ${
>=!$(JgX
bA*T1Db,t>
O ]Stf7]%;
O~u@J'4
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 'boAv%1_sa
nv-_\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。 +jrMvk"
:978D0}{p
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 %>)&QZig/
$ 8WJ$73
f^D4aEU
C+<z;9`
63Dm{
2i}F
我写的一个用于分页的类,用了泛型了,hoho *=~X1s
lBcRt)_O7
java代码: qcdENIy0b
]>'yt #]
3!<} -sW4
package com.intokr.util; ?:1)=I<A4
1u\kxlZ
import java.util.List; x}*Y =Xh
z ;KUIWg
/** v:w $l{7
* 用于分页的类<br> =^D{ZZw{
* 可以用于传递查询的结果也可以用于传送查询的参数<br> NX5NE2@^qH
* uom~,k$|
* @version 0.01 /ar/4\b
* @author cheng _!'sj=n]q
*/ _0c$SK
public class Paginator<E> { ,Z1W3;O
privateint count = 0; // 总记录数 0Q= o"@
privateint p = 1; // 页编号 GK.U_` 4?
privateint num = 20; // 每页的记录数 8~s-@3J
privateList<E> results = null; // 结果 AcCM
W@e
`h+1u`FJ
/** u,Rhm-`
* 结果总数 Vo-]&u&cr
*/ 4}t&AW4
publicint getCount(){ v*.#LJEm
return count; #&jr9RB
} 9'S~zG%{
Uk0]A
publicvoid setCount(int count){ dtT2h>h9
this.count = count; DHO+JtO
} q*kieqG
SjRR8p<
/** !&=%#i
* 本结果所在的页码,从1开始 D8I)3cXa'
* zcTY"w\b
* @return Returns the pageNo. :1JICxAU
*/ .7EZB
publicint getP(){ &ivPY
return p; }bxx]rDl
} `+go|
5N2
Q8sCI An{
/**
%=O$@.%Zc
* if(p<=0) p=1 HxmCKW!
* YvP u%=eF
* @param p [
queXDn"m
*/ wcI4Y0+J
publicvoid setP(int p){ WP-'gC6K=
if(p <= 0) Fo1|O&>
p = 1; mlmXFEC
this.p = p; 1 n86Mp1.e
} $EuWQq7OI2
:%hxg
/** ~"ij,Op,3
* 每页记录数量 3M&IMf,/@
*/ k-M-=VvA
publicint getNum(){ W%k0_Y/5
return num; P=jbr"5Q:
} U2(|/M+
ZdJer6:Z}
/** ?-e'gC
* if(num<1) num=1 b@&ydgmaQ
*/ 43?J~}<Vs
publicvoid setNum(int num){ +J~q:b.
if(num < 1) XS'0fq a
num = 1; G2x5% `
this.num = num; 6c/Tm0[
} A-dL_3
H#joc0?P
/** FSvtiNW<
* 获得总页数 I@f">&^
*/ Cl+TjmOV\`
publicint getPageNum(){ #VwA?$4g`
return(count - 1) / num + 1; q;kN+NK64
} Wo^r#iRko
vG<JOxP
/** >iCkvQ
* 获得本页的开始编号,为 (p-1)*num+1 Qs*6wF
*/ M!s@w%0?'
publicint getStart(){ \q8D7/q
return(p - 1) * num + 1; =lf&mD
_/
} Hkv4t5F
U*'
YGv
/** 62Ab4!
* @return Returns the results. Q.Kr;64G
*/ |x AwiF_
publicList<E> getResults(){ wghz[qe
return results; 3psCV=/z
} \c! LC4pE
F H'jP`
public void setResults(List<E> results){ N>fC"
this.results = results; xwH+Q7O&l
} SRN:!-
35;)O -
public String toString(){ BHwQB2t gc
StringBuilder buff = new StringBuilder cs ?@Ri=g
J]f\=;z;<a
(); at/v.U|F
buff.append("{"); "=unDpq]
buff.append("count:").append(count); I54O9Aoy
buff.append(",p:").append(p); I
[J0r
buff.append(",nump:").append(num); ,T{(t@
buff.append(",results:").append U=C8gVb{Hq
"Q~6cH[#
(results); |f^/((:D
buff.append("}"); ua['rOnU
return buff.toString(); dQ8}mH!
} {. N" 6P
#lax0IYY=
} 1GY[1M1^
N[j7^q7Xt
#=f ]"uM<