Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 I^ >zr.zA
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ^@19cU?q
=OHDp7GXO>
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 d.}rn"(z
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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 "LxJPt\
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。 ^Q OvK>W<
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分页支持类: <Ihn1?
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java代码: .N'UnKz
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package com.javaeye.common.util; *ap#*}r!Nk
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import java.util.List; C=b5[, UCB
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publicclass PaginationSupport { W
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publicfinalstaticint PAGESIZE = 30; #rC/y0niH
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privateint pageSize = PAGESIZE; 0iB1_)~
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privateList items; Y~:7l5C
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privateint totalCount; .o8Gi*PEY
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privateint[] indexes = newint[0]; 8xv\Zj +
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privateint startIndex = 0; G`P+J
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public PaginationSupport(List items, int {Eb6.
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totalCount){ `^}9= Q'r
setPageSize(PAGESIZE); Fi`:G}
setTotalCount(totalCount); Bx qCV%9o
setItems(items); BY d3 rI
setStartIndex(0); ={Hbx>p
} Sce9R?II
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public PaginationSupport(List items, int 5jLDe~
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totalCount, int startIndex){ #n7{ 3)
setPageSize(PAGESIZE); \[&]kPcDl
setTotalCount(totalCount); ')aYkO{%sb
setItems(items); X<{m;T `
setStartIndex(startIndex); &Xav$6+Z1J
} Ll`apKr
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q
public PaginationSupport(List items, int YH>n{o;-
?
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totalCount, int pageSize, int startIndex){ o(zg_!P
setPageSize(pageSize); 21[F%,{.),
setTotalCount(totalCount); E$wB bm
setItems(items); ivq4/Y]-X
setStartIndex(startIndex); O+N-x8W{
} /$=^0v+
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publicList getItems(){ 1:t>}[Y
return items; 'FhnSNT(4=
} |3LMVN
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publicvoid setItems(List items){ 7`}z7nk
this.items = items; +\%zy=
} xlLS`
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publicint getPageSize(){ Ydx5kUJV<
return pageSize; ;k8}D*?8
} }0(
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publicvoid setPageSize(int pageSize){ S(6ZX>wv:
this.pageSize = pageSize; "ir*;|
} EHZSM5hu
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publicint getTotalCount(){ 7yp*I[1Qf>
return totalCount; ?>Aff`dHY
} m
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publicvoid setTotalCount(int totalCount){ .IXwa,
if(totalCount > 0){ &; \v_5N6
this.totalCount = totalCount; 8=~>B@'
int count = totalCount / 5[_8N{QC;
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pageSize; +$t%L
if(totalCount % pageSize > 0) S2)S/ nf
count++; Qx;A; n!lw
indexes = newint[count]; 0, /x#
for(int i = 0; i < count; i++){ &iZYBa
indexes = pageSize * kdCOcJB
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i; \0h/~3
} kP$gl|
}else{ 37xxVbik
this.totalCount = 0; YW<2:1A|
} F6p1 VFs
} {%{GZ
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publicint[] getIndexes(){ J|-HZ-Wk|J
return indexes; sFK<:ka
} jhv1 D'>6
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publicvoid setIndexes(int[] indexes){ \]xYV}(FO
this.indexes = indexes; $4
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} {M/c!
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publicint getStartIndex(){ T;@>O^
return startIndex; ]'(7T#
} tHbPd.^
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publicvoid setStartIndex(int startIndex){ ?LI9F7n
if(totalCount <= 0) p8l#=]\;
this.startIndex = 0; L?x?+HPY.
elseif(startIndex >= totalCount) Z@!W?Ed
this.startIndex = indexes I&8m5F?$`
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[indexes.length - 1]; #~;8#!X
elseif(startIndex < 0) 2<Bv=B
this.startIndex = 0; S:/RYT"
else{ Ky#B'Bh}`g
this.startIndex = indexes t[hocl/6
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[startIndex / pageSize]; +E|ouFI
} ]0 RX o3
} % Au$E&sj
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publicint getNextIndex(){ *]R0z|MW
int nextIndex = getStartIndex() + ?4e6w
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pageSize; I^(#\vRW
if(nextIndex >= totalCount) aLt{X)?
return getStartIndex(); p"IS"k%
else c8tC3CrKp=
return nextIndex; siYRRr
} 2Fg t)`{!
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publicint getPreviousIndex(){ ,$zlw\
int previousIndex = getStartIndex() - BK9x`Oo 2
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pageSize; Uy5 !H1u
if(previousIndex < 0) PMhhPw]
return0; 1D p@n
else 'h>5&=r
return previousIndex; _/~ ,a
} c[_^bs>k
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} Q4Fq=kTE
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抽象业务类 )nHE$gVM
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java代码: Q &7)vs
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/** ttFY
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* Created on 2005-7-12 q%k(M[
*/ a`b zFu{
package com.javaeye.common.business; dIpW!Pj^
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import java.io.Serializable; 1"&;1Ts
import java.util.List; 6$s0-{^
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import org.hibernate.Criteria; b>=Wq
import org.hibernate.HibernateException; {XD/8m(hN|
import org.hibernate.Session; |4S?>e
import org.hibernate.criterion.DetachedCriteria; 6QLQ1k`
import org.hibernate.criterion.Projections; 3
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import $@_t5?n``F
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org.springframework.orm.hibernate3.HibernateCallback; N^
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import M?xpwqu\
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org.springframework.orm.hibernate3.support.HibernateDaoS mvq7G
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upport; 1%spzkE 3P
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import com.javaeye.common.util.PaginationSupport; 9Ue7
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public abstract class AbstractManager extends %8bzs?QI
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HibernateDaoSupport { ^{*f3m/
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privateboolean cacheQueries = false; %x}&=zx0*1
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privateString queryCacheRegion; wY3|#P
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publicvoid setCacheQueries(boolean w=D%D8 r2
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cacheQueries){ O~h94 B`
this.cacheQueries = cacheQueries; :'y{dbKp"
}
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publicvoid setQueryCacheRegion(String J1tzHa6
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queryCacheRegion){ t{Hh&HX
this.queryCacheRegion = 6Lg!Lodu
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queryCacheRegion; \5Vp6^
} L19MP
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publicvoid save(finalObject entity){ +ze}0lrEL
getHibernateTemplate().save(entity); ]yAEjn9cN
} ~v2V`lxh
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publicvoid persist(finalObject entity){
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getHibernateTemplate().save(entity); \E$1lc
} ,u}<Ws8N
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publicvoid update(finalObject entity){ 8: HSPDU.
getHibernateTemplate().update(entity); [jl2\3*
} -BA"3 S
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publicvoid delete(finalObject entity){ (0E U3w?]
getHibernateTemplate().delete(entity); xH<'GB)
} -F"d0a,
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publicObject load(finalClass entity, ^:4L6
(Sth:{;
finalSerializable id){ H>? :U]
return getHibernateTemplate().load J>=1dCK
)=jT_?9b
(entity, id); 908ayfVI
} T8$%9&j!UE
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publicObject get(finalClass entity, 5v|H<wPp
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finalSerializable id){ &/](HLdF
return getHibernateTemplate().get iV?` i
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(entity, id); <ROpuY\!l
} hZAG (Z
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publicList findAll(finalClass entity){ <S]KaDu^
return getHibernateTemplate().find("from +D:83h{
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" + entity.getName()); 4~O6$;!|~
} pC*BA<?Rg
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publicList findByNamedQuery(finalString nVxq72o@
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namedQuery){ *(k%MTG
return getHibernateTemplate X[V?T>jsM
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().findByNamedQuery(namedQuery); }>V/H]B
} ~xS@]3n=
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publicList findByNamedQuery(finalString query, |~SE"
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finalObject parameter){ {3hqp*xl
return getHibernateTemplate %a5t15 9
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().findByNamedQuery(query, parameter); 7))\'\
} %X;7--S%?g
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publicList findByNamedQuery(finalString query, oEJaH
*p=fi
finalObject[] parameters){ RI-A"cc6A
return getHibernateTemplate 7_DG 5nT
*=Doe2(!C
().findByNamedQuery(query, parameters); `gt:gx>a
} aD2*.ln><
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publicList find(finalString query){ {O)YwT$`
return getHibernateTemplate().find :q^R
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(query); Y+g,pX
} Q!yb16J
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publicList find(finalString query, finalObject 6B#('gxO
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parameter){ s2%V4yy%
return getHibernateTemplate().find 8h|M!/&2
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(query, parameter); 2{-!E ^g
} 4U?<vby
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public PaginationSupport findPageByCriteria i'HPRY
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T
(final DetachedCriteria detachedCriteria){ bDDqaO ,8
return findPageByCriteria zG#wu
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Yt+h2ft!
} 9@ndi u[
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public PaginationSupport findPageByCriteria bKMWWJf*'
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(final DetachedCriteria detachedCriteria, finalint .k@^KY
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startIndex){ gWOt]D/
return findPageByCriteria #{$1z;i?f
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(detachedCriteria, PaginationSupport.PAGESIZE, H\E7o"m
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startIndex); URA0ey`
} ]tB@kBi "
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public PaginationSupport findPageByCriteria vT c7an6fy
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(final DetachedCriteria detachedCriteria, finalint %<}<'V0
:"QfF@Z{
pageSize, *0y{ ~@
finalint startIndex){ m`y9Cuk
return(PaginationSupport) K]/Od
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getHibernateTemplate().execute(new HibernateCallback(){ BLn_u,3
publicObject doInHibernate {6*#3m
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(Session session)throws HibernateException { |sIr?RL{C
Criteria criteria = Nxk(mec"
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detachedCriteria.getExecutableCriteria(session); gCuAF$o
int totalCount = D!F 2l_
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((Integer) criteria.setProjection(Projections.rowCount *geN[[
>&U@f
()).uniqueResult()).intValue(); ST
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criteria.setProjection m#e*c[*G
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(null); C\}/"
List items = lpgd#vr
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criteria.setFirstResult(startIndex).setMaxResults RWKH%C[Yd
FhkkWWL
(pageSize).list(); +G*JrwJ&=
PaginationSupport ps = c_.-b=zm
9QwKakci
new PaginationSupport(items, totalCount, pageSize, mwC=o5O
bsS:"/?>
startIndex); ]<XR]FHx)
return ps; v^N`IJq
} ~"K,7sw!Y
}, true); O
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} +=BAslk
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public List findAllByCriteria(final 7
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DetachedCriteria detachedCriteria){ 9\JQ7$B
return(List) getHibernateTemplate wN=;i#
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().execute(new HibernateCallback(){ 0 1V^L}
publicObject doInHibernate iW%8/$
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(Session session)throws HibernateException { Bv6K$4
Criteria criteria = By)u-)g9
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detachedCriteria.getExecutableCriteria(session); z>m=h)9d~
return criteria.list(); P7.' kX9
} o-C#|t3hH
}, true); SaOYu &>
} ;# uZhd
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public int getCountByCriteria(final
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*L4`$@l8
DetachedCriteria detachedCriteria){ 0Ua%DyJ
Integer count = (Integer) Q~{H@D`<
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getHibernateTemplate().execute(new HibernateCallback(){ Ztr Cv?
publicObject doInHibernate _hu")os
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(Session session)throws HibernateException { %McE`155
Criteria criteria = eW J`$"z
*{
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detachedCriteria.getExecutableCriteria(session); b^0}}12
return Jl3g{a
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criteria.setProjection(Projections.rowCount kF"@Ngv.
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()).uniqueResult(); vw,rF`LjZ
} [* ?Awf`
}, true); {X(:jAy
return count.intValue(); 6Orum/|h
} ~\LCvcY"X
} 6 5N~0t
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用户在web层构造查询条件detachedCriteria,和可选的 *t[. =_v
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 #S&Tkip]"W
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PaginationSupport的实例ps。 2'EUy@0
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ps.getItems()得到已分页好的结果集 bef_rH@`
ps.getIndexes()得到分页索引的数组 Oy U
ps.getTotalCount()得到总结果数 ~T&<CTh
ps.getStartIndex()当前分页索引 &0 >Loja`^
ps.getNextIndex()下一页索引 .Asv%p[W
ps.getPreviousIndex()上一页索引 u/cg|]x&T
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 n a9sm
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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 ~0beuK&p
kY*rb_2j
一下代码重构了。 }VS5gxI1.
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我把原本我的做法也提供出来供大家讨论吧: q#<^ ^4U
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首先,为了实现分页查询,我封装了一个Page类: 9E>xIJ@J2T
java代码: ]]Cb$$Td
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/*Created on 2005-4-14*/ 0TQ$C-%
package org.flyware.util.page; ]IoUwg pI)
+=O5YR!{
/** tmQH|'>>
* @author Joa "jG}B.l=,
* ?OkWe<:4
*/ sBr_a5QQ#
publicclass Page { vI>>\.ED
.zi_[
/** imply if the page has previous page */ o4|M0
privateboolean hasPrePage; !o:f$6EA~C
D#3\y*-y?
/** imply if the page has next page */ rg^'S1x|
privateboolean hasNextPage; -i0~]*
j'A_'g'^
/** the number of every page */ dBz/7&Q
privateint everyPage; Pi]19boM.
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/** the total page number */ d3D] k,
privateint totalPage; N@t|7~
B} lvr-c#
/** the number of current page */ ,yiX# ;j
privateint currentPage; Mu+0<>
~ _/(t'9
/** the begin index of the records by the current Qk:Y2mL
8fl`r~bqZ
query */ wne,e's}
privateint beginIndex; LDPUD'
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/** The default constructor */ wB.&}p9p
public Page(){ |5lk9<z
)h7<?@wv&
} bbE!qk;hEP
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/** construct the page by everyPage nAv#?1cjz
* @param everyPage aDU<wxnSvO
* */ k$blEa4
public Page(int everyPage){ Ff)8Q.m
this.everyPage = everyPage; i<#QW'R (
} .%xn&3
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/** The whole constructor */ MN\HDKN
public Page(boolean hasPrePage, boolean hasNextPage, 4K\G16'$v
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pH9VTM.*
int everyPage, int totalPage, \NPmym_6J
int currentPage, int beginIndex){ hgPa6Kd
this.hasPrePage = hasPrePage; 0Tx6zO
this.hasNextPage = hasNextPage; Ayxkv)%:@)
this.everyPage = everyPage; b,7k)ND1F
this.totalPage = totalPage; Mk"^?%PxT
this.currentPage = currentPage; eA2@Nkw~)
this.beginIndex = beginIndex; ofm#'7P 0
} -|$@-fY;
bCRV\myd`
/** ,E S0NA
* @return C5o#i*|
* Returns the beginIndex. Y]'Z7<U}*E
*/ Va"0>KX
publicint getBeginIndex(){ <^#,_o,!
return beginIndex; ;U/&I3dzV
} Z^3rLCa
=$'6(aDH
/** >mwlsL~X
* @param beginIndex
&u$Q4
* The beginIndex to set. lXW%FH6c+
*/ wr$("A(
publicvoid setBeginIndex(int beginIndex){ f%][}NN)Xr
this.beginIndex = beginIndex; DX#Nf""Pw
} C0T;![/4A
XO.jl" xu
/** xQ7l~O
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* @return R@1 xt@?
* Returns the currentPage. ,LHn90S
*/ \V;F/Zy(
publicint getCurrentPage(){ Yl
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return currentPage; K@
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} (S>C#A=E\
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/** V(H1q`ao9
* @param currentPage )}Hpi<5N
* The currentPage to set. B-*+r`@Bd
*/ Vh|*p&
publicvoid setCurrentPage(int currentPage){ ^UP`%egR
this.currentPage = currentPage; *7uH-u"5d
} g];!&R-
KI"#f$2&
/** u|\1hLXX
* @return h79}qU
* Returns the everyPage. Q*D;U[
*/ 5%Y3 Kwyy
publicint getEveryPage(){ ? >7[7(|
return everyPage; R$R *'l
} Xr,1&"B&t
">\?&0
/** yuh *
* @param everyPage <$D`Z-6
* The everyPage to set. =*oJEy"
*/ N=V==Dbu-
publicvoid setEveryPage(int everyPage){ P\E<9*V
this.everyPage = everyPage; ]%;:7?5l
} 9)l$ aBa
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/** tHU 2/V:R
* @return U7?;UCmX
* Returns the hasNextPage. xK>*yV
*/ NDN7[7E
publicboolean getHasNextPage(){ d-oMQGOklb
return hasNextPage; /T"+KU*
} Sj3+l7S?
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/** wo3d#=
* @param hasNextPage eb?x9h
* The hasNextPage to set. &sl0W-;0
*/ w2?3wrP3
publicvoid setHasNextPage(boolean hasNextPage){ >R'F,
this.hasNextPage = hasNextPage; z}.e]|b^H
} x'8x
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/** [F+}V,
* @return 'lH|eU&-
* Returns the hasPrePage. Ugr!"Q#M
*/ %aP!hy
publicboolean getHasPrePage(){ u^&^UxCA
return hasPrePage; N:^n('U&j
} jVEGj5F;N
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/** %U/(|wodd
* @param hasPrePage 49eD1h3'X[
* The hasPrePage to set. |44Ploz2b
*/ |NlO7aQ>2H
publicvoid setHasPrePage(boolean hasPrePage){ ~?l |
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this.hasPrePage = hasPrePage; \UA[
} (|2t#'m
."g`3tVK
/** B.=FSow
* @return Returns the totalPage. .7J#_*NV
* RTYvS5G
*/ <3nMx^
publicint getTotalPage(){ Usvl}{L[
return totalPage; jVi) Efy
} Zj(AJ* r
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/** )+#` CIv
* @param totalPage MxKS4k
* The totalPage to set. ibcRU y0%
*/ nkPh,X\N0
publicvoid setTotalPage(int totalPage){ =F|{#F
this.totalPage = totalPage; I{|O "8
} U4'#T%*
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} y
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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 }{Pp]*I<A
-OV&Md:~
个PageUtil,负责对Page对象进行构造: 1C+13LE$U
java代码: &C_j\7Dq
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/*Created on 2005-4-14*/ rI{; I DV
package org.flyware.util.page; M-VX;/&FR
ScOK)nL"
import org.apache.commons.logging.Log; H*n-_{h"t
import org.apache.commons.logging.LogFactory; !)f\%lb
zpn9,,~u
/** yZY \MB/
* @author Joa gjyYCjF
* k t#fMd$
*/ _;S-x
publicclass PageUtil { LH.]DVj
tAd%#:K
privatestaticfinal Log logger = LogFactory.getLog ,L2ZinU:
l\H=m3Bg
(PageUtil.class); d0!5j
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/** 8Al{+gx@?
* Use the origin page to create a new page v4TQX<0s
* @param page ktXM|#
* @param totalRecords ?FZ HrA
* @return l'rja.\
*/ P= BZ+6DS
publicstatic Page createPage(Page page, int EU 6 oQ
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totalRecords){ e*kpdS~U&
return createPage(page.getEveryPage(), e(&v"}Ef`
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page.getCurrentPage(), totalRecords); x;.Jw6g
} 9.M4o[
t.y2ff<[U
/** H7Rx>h_
* the basic page utils not including exception x;KOqfawv
.NC!7+1m
handler X,%
0/6*]
* @param everyPage e)k9dOR
* @param currentPage HyQJXw?A:
* @param totalRecords `{h*/Q
* @return page qBQ?HLK-
*/ k
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publicstatic Page createPage(int everyPage, int Qy<P463A(l
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currentPage, int totalRecords){ ~vhE|f
everyPage = getEveryPage(everyPage); BwEN~2u6
currentPage = getCurrentPage(currentPage); _.Nbt(mz
int beginIndex = getBeginIndex(everyPage, SHxNr(wJ<Q
s\(k<Ks
currentPage); |^I0dR/w:
int totalPage = getTotalPage(everyPage, pU}(@oy
!-x$L>1$
totalRecords); Ta0|+IYk<
boolean hasNextPage = hasNextPage(currentPage, *;slV3
Rok7n1gW
totalPage); B]wk+8SMY.
boolean hasPrePage = hasPrePage(currentPage); qr^3R&z!}
8'[7
)I=
returnnew Page(hasPrePage, hasNextPage, &{hL&BLr
everyPage, totalPage, OZF
rtc+
currentPage, 6'5 7
wssRA?9<
beginIndex); 0S_~ \t
} *%NT~C
q
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privatestaticint getEveryPage(int everyPage){ #Y`~(K47
return everyPage == 0 ? 10 : everyPage; AT3cc
} z,
)6"/;
l/GGCnO/
privatestaticint getCurrentPage(int currentPage){ 6vo;!V6
return currentPage == 0 ? 1 : currentPage; ,4e:I.b
} G6P?2@
H5B:;g@
privatestaticint getBeginIndex(int everyPage, int qJs<#MQ2
L| +~"'l
currentPage){ 286;=rN]*
return(currentPage - 1) * everyPage; 1CD+B=pQG
} 4jMFr,
[Td4K.c
privatestaticint getTotalPage(int everyPage, int bdrg(d6
ZohCP
totalRecords){ )p0^zv{
int totalPage = 0; ItVWO:x&v
".V$~n(
if(totalRecords % everyPage == 0) #aJ(m&
totalPage = totalRecords / everyPage; . B9iLI
else drP=A~?&:
totalPage = totalRecords / everyPage + 1 ; Tya1/w4
jl$ece5v
return totalPage; RDi]2
} &MQmu,4
NjScc%@y
privatestaticboolean hasPrePage(int currentPage){ e7Z32P0ls
return currentPage == 1 ? false : true; Q7\w+ANf0
} ^7U
G$A
_$YkM,
privatestaticboolean hasNextPage(int currentPage, <n];mfh1
}Yzco52
int totalPage){ )JLdO*H
return currentPage == totalPage || totalPage == Y@vTaE^w3
F3@phu${
0 ? false : true; P|tO<t6/9*
} | `2RShu
!}#8)?p
'4+
ur`
} :Uzm
_LEK%
TOB-aAO
%+W{iu[|
z,[Hli*0
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 OUPUixz2Z
7hD>As7`/
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 wo;~7K
7Jyy z,!5
做法如下: 8oy^Xc+
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 |}s*E_/[
b.JuI
的信息,和一个结果集List: VK\X&Y3l
java代码: jKAEm
DZ'P@f)]
{0Yf]FQb-a
/*Created on 2005-6-13*/ y*jp79G
package com.adt.bo; T= y}y
O~#!l"0 L+
import java.util.List; 1y@i}<9F
ah4N|zJ>v
import org.flyware.util.page.Page; _/s$ZCd
)np:lL$$
/** Olt?~}
* @author Joa urs,34h
*/ F3[T.sf
publicclass Result { L2[($l
O'p9u@kc
private Page page; ` xEx^P^7
*MFIV02[N
private List content; MC&` oX[
(&Kk7<#`
/** 5FPM`hLT
* The default constructor B?gOHG*vd>
*/ Drgv`z
public Result(){ +<Nn~1
super(); -e"H ^:
} 6xx<Y2@
~~/|dh5
/** 9IdA%RM~mH
* The constructor using fields \$~|ZwV{
* $t'MSlF
* @param page HTv2#
* @param content hohfE3rd
*/ Fbr;{T
.
public Result(Page page, List content){ 6m/r+?'
this.page = page; S:#lH?<_
this.content = content; J\}twYty
} I;,77PxD
eH'av}
/** 3)t.p>VgO
* @return Returns the content. Fj 8z
*/ v|_K/|
publicList getContent(){ q"CVcLi9
return content; \"w"$9o6
} T$)^gHS
r..iko]T
/** *2>&"B09`
* @return Returns the page. U*rcd-@
*/ DD+7V@
public Page getPage(){ :DK {Vg6
return page; 8?B!2
} U|H=Y"pL
#X+JHl
/** IEL%!RFG
* @param content {K~ 'K+TPu
* The content to set. :;%2BSgFU
*/ p}}R-D&K
public void setContent(List content){ /wGM#sFH
this.content = content; '|6]_
} @(EAq<5{
1SQ3-WUs
/** Ljm[?*H#
* @param page ;Zcswt8]u
* The page to set. zH 72'"w
*/ m+`cS=-.
publicvoid setPage(Page page){ nI?[rCM
this.page = page; >4x(e\B
} ;>%r9pz ~
} X~bX5b[P
\Gef \
rm'SOJVA
]6k\)#%2
f=+mIZ
2. 编写业务逻辑接口,并实现它(UserManager, JMCKcZ%N
ydEoC$?0
UserManagerImpl) xWH.^o,"
java代码: >>4qJ%bL
sU<Wnz\[
}`@vF|2L
/*Created on 2005-7-15*/ h6Ub}(Ov
package com.adt.service; :^lI`9'*R
Gq)]s'r2
import net.sf.hibernate.HibernateException; q~F|
5;Czu(iH$
import org.flyware.util.page.Page; dZl5Ic
1/B>XkCJ
import com.adt.bo.Result; /s&9SYF
tn\yI!a
/** /obfw^
* @author Joa vQG5*pR*w
*/ *}qWj_RT
publicinterface UserManager { eI}aQ]$ED
]"As1"
public Result listUser(Page page)throws [-1^-bb
@}u*|P*
HibernateException; h%na>G
AEI>\Y
} x
M/+L:_<
Ys9[5@7
caR<Kb:;*
,$L4dF3
.^33MWu6
java代码: aH(J,XY
,Q$q=E;X
GTPHVp&y
/*Created on 2005-7-15*/ 5J.bD)yrP
package com.adt.service.impl; "m$##X\
|fJ};RLI"
import java.util.List; IJp-BTO{V
\[i1JG
import net.sf.hibernate.HibernateException; =+-UJo5
[ZwjOi:)
import org.flyware.util.page.Page; wc@X.Q[
import org.flyware.util.page.PageUtil; fCn^=8KOZ
r| wS<cA2
import com.adt.bo.Result; s-!ArB,
import com.adt.dao.UserDAO; #pow ub
import com.adt.exception.ObjectNotFoundException; e;q!6%
import com.adt.service.UserManager; J7$5s
&{n.]]%O.
/** ?3`UbN:
* @author Joa nsC3
*/ OX0%C.K)hZ
publicclass UserManagerImpl implements UserManager { dh iuI|?@
CI0C1/:@
private UserDAO userDAO; / &5,3rU.G
!;v|' I
/** B)g[3gQ
* @param userDAO The userDAO to set. z (wc0I
*/ Xza(k
publicvoid setUserDAO(UserDAO userDAO){ qOtgve`jX
this.userDAO = userDAO; ;?iW%:_,
} '3fu
e{K 215
/* (non-Javadoc) 1N-\j0au
* @see com.adt.service.UserManager#listUser prF%.(G2)
I-*S&SiXjI
(org.flyware.util.page.Page) %)W2H^
*/ B%b4v
public Result listUser(Page page)throws hd<c&7|G'
}@+0/W?\.
HibernateException, ObjectNotFoundException { YnAm{YyI
int totalRecords = userDAO.getUserCount(); 5coyr`7mP
if(totalRecords == 0) $k%2J9O
throw new ObjectNotFoundException 7(8;to6(
<{cQM$#
("userNotExist"); \'D0'\:vz
page = PageUtil.createPage(page, totalRecords); !CT5!5T
List users = userDAO.getUserByPage(page); hx %v+/
returnnew Result(page, users); Rtl"Ub@HV
} =s2*H8]
Qn.om=KDs@
} #OD/$f_
u|TeE\0
q,|j]+9q
kJsN|=
+gtbcF@rx
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 mSF(q78?
E
A1?)|}n
询,接下来编写UserDAO的代码: WiR(;m<g
3. UserDAO 和 UserDAOImpl: ] 72`};
java代码: *zvx$yJ?
(exa<hh
#rfiD%c
/*Created on 2005-7-15*/ UECK:61Me
package com.adt.dao; f+,qNvBY/
[!#L6&:a8
import java.util.List; w-MCZwCr)
q"8ea/
import org.flyware.util.page.Page; K=h9Ce
/]Md~=yNp
import net.sf.hibernate.HibernateException; h2]P]@nW;W
xj;H&swo
/** !ons]^km
* @author Joa MaQqs=
*/ :>f )g
publicinterface UserDAO extends BaseDAO { giw &&l=_
3ym',q
publicList getUserByName(String name)throws YfKdR"i+.
WO>nIo5Y
HibernateException; e\zm7_+i{
u^I|T.w<r6
publicint getUserCount()throws HibernateException; {]@= ijjf
e 2oa($9
publicList getUserByPage(Page page)throws O;jrCB
aSQ#k;T[
HibernateException; LCKV>3+_#
y/7\?qfTk
} xdt-
;w|
Q\7h`d%)
Ie#Bkw'*
Jk
n>S#SZ
A]oV"`f
java代码: ={&j07,*a
J<h$
wM
'-XXo=>0MV
/*Created on 2005-7-15*/ v$wIm, j
package com.adt.dao.impl; ;$wVu|&
N5
6g+,w%)
import java.util.List; } (73Syl#
3;A)W18]
import org.flyware.util.page.Page; SO'vpz{
N<VJ(20y
import net.sf.hibernate.HibernateException; y?? XIsF
import net.sf.hibernate.Query; \X D6 pr@
d/kv|$XW
import com.adt.dao.UserDAO; ndMA-`Ny,
dkTX
/** &n:.k}/P
* @author Joa QlU8uI[dk
*/ `1fY)d^ZS
public class UserDAOImpl extends BaseDAOHibernateImpl WW~sNC\3`(
\Uq(Zga4)
implements UserDAO { ?%[@Qb=2
4!no~ $b
/* (non-Javadoc) +iRh
* @see com.adt.dao.UserDAO#getUserByName yN(%-u"
Lk}J8 V^2
(java.lang.String) 7~.9=I'A
*/ V {ddr:]4
publicList getUserByName(String name)throws u\;C;I-? '
YUy0!`!`
HibernateException { F{;((VboN
String querySentence = "FROM user in class +VOK%8,p
BUXpCxQ
com.adt.po.User WHERE user.name=:name"; c 3)jccWTc
Query query = getSession().createQuery R!gEwTk
LFRlzz;
(querySentence); j'"J%e]
query.setParameter("name", name); .4!=p*Y
return query.list(); r52gn(,
} A#iV=76_
_F|Ek ;y%
/* (non-Javadoc) `7V]y-
* @see com.adt.dao.UserDAO#getUserCount() f(y:G^V
*/ S3Xl
publicint getUserCount()throws HibernateException { 'e'cb>GnA
int count = 0; 5K8^WK
String querySentence = "SELECT count(*) FROM $5%SNzzl
srrgvG,
user in class com.adt.po.User"; z5*'{t)
Query query = getSession().createQuery u <v7;dF|s
?J>
(querySentence); 7?w*]
count = ((Integer)query.iterate().next Ne1$ee.NE
Si;H0uP O
()).intValue(); MeZf*'
J
return count; H9Q&tl9
} &Hs!:43E-<
{8bSB.?R
/* (non-Javadoc) U 0P~
* @see com.adt.dao.UserDAO#getUserByPage G
mA<
g
TJXT-\Vk
(org.flyware.util.page.Page) w@w(-F!%l
*/ 8P&:_T!
publicList getUserByPage(Page page)throws |z^^.d~a0
.V8Lauz8
HibernateException { z 1X` o
String querySentence = "FROM user in class <*cikXS
LG#t<5y~
com.adt.po.User"; bq0zxg%
Query query = getSession().createQuery JYHl,HH#z
3eQ&F~S
(querySentence); q9s=~d7
query.setFirstResult(page.getBeginIndex()) LyFN.2qw
.setMaxResults(page.getEveryPage()); ' %o#q6O
return query.list(); <x>Mo
} %| Lfuz*
^SrJu:Q_
} OYn}5RN
FXkM#}RgNm
IF:;`r@%
"oO%`:pb
/jJw0 5;L
至此,一个完整的分页程序完成。前台的只需要调用 FJ)$f?=Qd
n,WqyNt*
userManager.listUser(page)即可得到一个Page对象和结果集对象 s`~IUNJ@P
'E""amIJ
的综合体,而传入的参数page对象则可以由前台传入,如果用 >}6%#CAf
_E.>`Q
webwork,甚至可以直接在配置文件中指定。 4^|3TntO
\(2sW^fY
下面给出一个webwork调用示例: &&>ekG9@
java代码: VRB;$
^s"R$?;h
dDLeSz$b
/*Created on 2005-6-17*/ I51@QJX
package com.adt.action.user; NqWdRU
nZYBE030
import java.util.List; /f;~X"!
ak!G8'w
import org.apache.commons.logging.Log; I9ep`X6Y
import org.apache.commons.logging.LogFactory; &gx%b*;`L0
import org.flyware.util.page.Page; Qq|57X)P*
f(MO_Sj]
import com.adt.bo.Result; O6^]=/wd
import com.adt.service.UserService; -6B4sZpzD
import com.opensymphony.xwork.Action; +@wD qc
-e:`|(Mo
/** Wvf
^N(
* @author Joa l2Rb\4
*/ $*fMR,~t&
publicclass ListUser implementsAction{ BnasI;yWb
3)ywX&4"L
privatestaticfinal Log logger = LogFactory.getLog 1p=]hC
?gGHj-HYJ
(ListUser.class); {R6ZKB
Btcy)LRk
private UserService userService; g3y+&Y_
t1x1,SL
private Page page; -(H0>Ap
tY4;F\e2|A
privateList users; =D"#U#>;7&
$~T4hv :
/* $6poFo)U+
* (non-Javadoc) CzrC%x y
* u]UOSf n
* @see com.opensymphony.xwork.Action#execute() 7-fb.V9
*/ }@d @3
publicString execute()throwsException{ \,0oX!<YY
Result result = userService.listUser(page); 2<}%kQ`
page = result.getPage(); L~N460
users = result.getContent(); h<<v^+m
return SUCCESS; IW] rb/H
} ysY*k` 5
lL0APT;
/** 6.yu-xm
* @return Returns the page. x7 ,5
*/ 7HYwLG:\~
public Page getPage(){ |+D!=
:x
return page; O?#7N[7
} FGq[\B
~*];pV]A[
/** BnF^u5kv %
* @return Returns the users. I{=Qtnlb
*/ Nu)NqFG,
publicList getUsers(){ NC6&x=!3
return users; g*+>H1}
} [v!f<zSQK
_7_Y={4=`
/** :?1Dko^
* @param page ?(_08O
* The page to set. *.w9c
*/ iuul7VR-%
publicvoid setPage(Page page){ >uEzw4w
this.page = page; ]u/sphPe
} )MT}+ai
tw)mepwB
/** ^E>3|du]O
* @param users -X6PRE5a2
* The users to set. 5~DJWi,
*/ Xne1gms
publicvoid setUsers(List users){ uHRsFlw
this.users = users; BDQsP$'6QT
} /Z}}(6T
+D*Z_Yh6
/** >9Vn.S
* @param userService 42ge3>
* The userService to set. rEz^
*/ zX i'kB
publicvoid setUserService(UserService userService){ TIg3`Fon
this.userService = userService; }"%N4(Kd
} KD.]i' d<
} w5 Li&m
+:/%3}`
:7;@ZEe
as=fCuJ
%^6F_F_jS
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, {?7Uj
w_V P
J
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 b*lkBqs$
MomwX
么只需要: ;8 lfOMf
java代码: vW@=<aS Z
<9b&<K:
es0hm2HT3
<?xml version="1.0"?> +jgSV.N
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork )0k53-h&
E92-^YY
1.0//EN" "http://www.opensymphony.com/xwork/xwork- [()koU#w.
3=V&K-
1.0.dtd"> F,CTZ~
7_[L o4_
<xwork> X2"/%!65{
O^rD HFj,
<package name="user" extends="webwork- @>7%qS
;<4a*;IO
interceptors"> &BSn?
:b!s2n!u
<!-- The default interceptor stack name X"*5+* z]
,<X9 Y2B
--> RPbZ(.
<default-interceptor-ref +aAc9'k
0<*<$U
name="myDefaultWebStack"/> q ZZK#,Qb
wb ;xRP"w
<action name="listUser" \z ) %$#I
62NsJ<#>
class="com.adt.action.user.ListUser"> pTuS*MYz
<param |5 ]X| v
iU:cW=W|M\
name="page.everyPage">10</param> ?\n>
AC
<result \
B%+fw
V28M lP
name="success">/user/user_list.jsp</result> yIE!j%u
</action> z0Z%m@
7-V/RChBm
</package> !p/goqT~dY
.jK4?}]
</xwork> tT._VK]o&R
Ew$C
;&9
*yGGBqd
lmhLM. 2
f?)-}\[IR{
"uf%iJ:%
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 u]G\H!WkQ
2>59q$|
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 og>uj>H&
f,Ghb~y
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 !TcJ)0
23jwAsSo
OcO3v'&
iJ|uvPCE
K|s,ru
我写的一个用于分页的类,用了泛型了,hoho Y\hBd$lQ~
6E}qL8'5x
java代码: L\iFNT}g`
V G~Vs@c(
KG{St{uJ
package com.intokr.util; @KUWxFak
EBmt9S
import java.util.List; #,v{Ihn
4`=mu}Y2
/** {7pli{`
* 用于分页的类<br> H%lVl8oQ
* 可以用于传递查询的结果也可以用于传送查询的参数<br> Xlt|nX~#;
* i{qgn%#}Y
* @version 0.01 9o!Bzy+_
* @author cheng x$(f7?s] 1
*/ 8a"%0d#
public class Paginator<E> { xe$_aBU
privateint count = 0; // 总记录数 ft
Wv~Eh
privateint p = 1; // 页编号 n._-!
WI
privateint num = 20; // 每页的记录数 N4HqLh23H
privateList<E> results = null; // 结果 ?Ss!e$jf
]J]h#ZHx
/** ^d73Ig:8q
* 结果总数 kAGBdaJ"
*/ !Xw5<J3L-
publicint getCount(){ <=C?e<Y
return count; BfiD9ka-z
} 9(<@O%YU
k~z Iy;AZ
publicvoid setCount(int count){ Qe(:|q_
this.count = count; _h1mF<\ X^
} S`Rs82>
T&7qC=E#5
/** 6D_D' ;o
* 本结果所在的页码,从1开始 MnW+25=N
* -`6+UkOV[x
* @return Returns the pageNo. ( &x['IR
*/ `~q <N
publicint getP(){ Q=yg8CQ
return p; DLNbo2C
} jb!i$/%w
18:%~>.!
/** 0+b1vhQ
* if(p<=0) p=1 Yc*;/T}
* K\c#ig
* @param p BTrn0
*/ ,UE83j8D^
publicvoid setP(int p){ P=G3:eX
if(p <= 0) uWE^hz"
p = 1; aC)!T
this.p = p; 8, >P
} )whA<lC
"kqPmeI
/** E8&TO~"a]e
* 每页记录数量 ,
++ `=o
*/ ufT`"i
publicint getNum(){ '1/i"yoW
return num; D.XvG _
} @Do= k
u\JNr}bL
/** FaJ &GOM,
* if(num<1) num=1 .#pU=v#/[
*/ UW
EV^ &"x
publicvoid setNum(int num){ Thit
if(num < 1) VY\&8n}e(
num = 1; SasJic2M
this.num = num; R{T$[$6S
} Xla~Yg
65^9
/** _:27]K:
* 获得总页数 x-3\Ls[I
*/ <2qr}K{'A
publicint getPageNum(){ Hj,A5#|=J
return(count - 1) / num + 1; P7~ >mm+
} #>+ HlT
Q]>.b%s[
/** N87B8rDl
* 获得本页的开始编号,为 (p-1)*num+1 HyWCMK6b
*/ u;c?d!E
publicint getStart(){ um0N)&iY
return(p - 1) * num + 1; M =r)I~
} #;nYg?d=
[cp+i^f
/** J/*`7Pd
* @return Returns the results. IO-Ow!
*/ [ibu/W$
publicList<E> getResults(){ vRO
_Q?
return results; M/gGoE{
} d>C$+v>
'b{]:Y
public void setResults(List<E> results){ `W*U4?M
this.results = results; D}X\Ca"h
} 8-77d^cprR
ySDH"|0
public String toString(){ 'q:`? nJ^
StringBuilder buff = new StringBuilder Y0-n\|
Jg|XH
L)
(); k\GcHI-
buff.append("{"); e**qF=HCw
buff.append("count:").append(count); u4h4.NHX
buff.append(",p:").append(p); k+pr \d ~
buff.append(",nump:").append(num); `+Q%oj#FF
buff.append(",results:").append ]GQG~H^
Q$@I"V&G.
(results); 9zy!Fq
buff.append("}"); ZExlGC
return buff.toString(); SI-Ops~e
} jtc]>]6i
NHZz _a=
} s,&Z=zt0R
JnM["Q=`
7O-x<P;