Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 i[/`9 AK
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 <%?!3 n*
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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 QERj`/g
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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 Z;~ 7L*|
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分页支持类: O;+
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java代码: =*{Ii]D
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package com.javaeye.common.util; ]FEDAGu
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import java.util.List; oy\U\#k
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publicclass PaginationSupport { rT_J6F5J
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publicfinalstaticint PAGESIZE = 30; [JYy
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privateint pageSize = PAGESIZE; :!yPR
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privateList items; &}r-C97
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privateint totalCount; d<RJH
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privateint[] indexes = newint[0]; Fv<3VKueK[
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privateint startIndex = 0; 5Nl?Km~
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public PaginationSupport(List items, int !v.
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totalCount){ [ji')PCAi;
setPageSize(PAGESIZE); kMZo7 y
setTotalCount(totalCount); I%l2_hs0V
setItems(items); qSt\ 6~
setStartIndex(0); -ImVXy]?
} a66Ns7Rb
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public PaginationSupport(List items, int f4Ob4ah!(
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totalCount, int startIndex){ OlP1Zd/l
setPageSize(PAGESIZE); q$PO.#
setTotalCount(totalCount); {F;"m&3Lt
setItems(items); ^hcK&
setStartIndex(startIndex); '^`iF,rg
} wZVLpF+7
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public PaginationSupport(List items, int Ca-.&$f
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totalCount, int pageSize, int startIndex){ @r=,:
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setPageSize(pageSize); o8Yq3N +
setTotalCount(totalCount); G
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setItems(items); 1zgM$p
setStartIndex(startIndex); qM<CBcON
} m48Ab`
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publicList getItems(){ Ibg~.>.u{
return items; '61>.u:2
} L+~XW'P?
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publicvoid setItems(List items){ 9_O6Sl
this.items = items; |w{C!Q8l
} wg<t*6&'x
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publicint getPageSize(){ <}T7;knO
return pageSize; B(f_~ ]
} +j %y#_~
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publicvoid setPageSize(int pageSize){ &?}A/(#
this.pageSize = pageSize; nk;^sq4M:
} a$\Bt_
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publicint getTotalCount(){ Xzl$Qc
return totalCount; Ym.{
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} {eVv%sbq
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publicvoid setTotalCount(int totalCount){ #r/5!*3
if(totalCount > 0){ @_wJN Qo`
this.totalCount = totalCount; s
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int count = totalCount / E 02Y,C
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pageSize; `{m,&[n
if(totalCount % pageSize > 0) %j/pln&
count++; ~~=]_lwyK%
indexes = newint[count]; eV~"T2!Sb
for(int i = 0; i < count; i++){ B#?rW*yEe
indexes = pageSize * uAV7T /'
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i; ra2{8 x
} zI\+]U'
}else{ ksTK'7*
this.totalCount = 0; 4)8e0L*[B?
} HYL['B?Wid
} )x~/qHt
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publicint[] getIndexes(){ 4Y1dkg1y
return indexes; FmFjRYA W
} J~n|5*cz
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publicvoid setIndexes(int[] indexes){ fjy7 gC2
this.indexes = indexes; m41%?uC/
} TV#>x!5!d
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publicint getStartIndex(){ RB6Q>3g
return startIndex; [%O f
} pRzL}-[/v
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publicvoid setStartIndex(int startIndex){ MiR$N
if(totalCount <= 0) ~FQHT?DAo
this.startIndex = 0; kBxEp/y
elseif(startIndex >= totalCount) W 1u!&:O
this.startIndex = indexes v*&jA8D
w!z*?k=Da
[indexes.length - 1]; X%iJPJLza
elseif(startIndex < 0) K7@|2;e
this.startIndex = 0; =XK}eQ_d
else{ |KY-kRN7
this.startIndex = indexes <LzxnTx=
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[startIndex / pageSize]; K|l}+:k
} *[m:4\
} _]- 4UA-
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publicint getNextIndex(){ A7,%'.k
int nextIndex = getStartIndex() + BzS\p3&
s 0_*^cZ
pageSize; (> _Lb
if(nextIndex >= totalCount) |rG)Q0H,
return getStartIndex(); )EQz9
else v~yw-}fk%
return nextIndex; H^54o$5
} w/"vf3}(9
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publicint getPreviousIndex(){ ^b|I^TN0
int previousIndex = getStartIndex() - =<7z
:]
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pageSize; hlZ{bO'f
if(previousIndex < 0) IC (:RtJ
return0; D.Cn`O}
else jm@,Ihz=wI
return previousIndex; ];"40 /X
} ecQ{ePoU
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} Srz8sm;
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抽象业务类 LokH4A17U
java代码: J3~%9MCJ
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/** ;']u}Nh
* Created on 2005-7-12 |Olz h63k:
*/ Kh[l};/F
package com.javaeye.common.business; Z^z{,
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import java.io.Serializable; +3o0GJ
import java.util.List; c;Tp_e@
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import org.hibernate.Criteria; ~]QQaP
import org.hibernate.HibernateException; }(
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import org.hibernate.Session; `/`iLso&-
import org.hibernate.criterion.DetachedCriteria; pgiZA?r*<
import org.hibernate.criterion.Projections; @eeI4Jz
import rks"y&&Nc
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org.springframework.orm.hibernate3.HibernateCallback; ?jUgDwc(w
import i{TPf1OY`M
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org.springframework.orm.hibernate3.support.HibernateDaoS 88,hza`#V
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upport; 8/(}Wet
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import com.javaeye.common.util.PaginationSupport; cu
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public abstract class AbstractManager extends +6$+]u]
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HibernateDaoSupport { sR>>l3H
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privateboolean cacheQueries = false; bf+C=A)s0
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privateString queryCacheRegion; %K')_NS@
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publicvoid setCacheQueries(boolean Yj>4*C9
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cacheQueries){ Md@x2Ja
this.cacheQueries = cacheQueries; "_\"S
} 6vAZLNG3
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publicvoid setQueryCacheRegion(String h U-FSdR
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queryCacheRegion){ =pi,]m
this.queryCacheRegion = Uq_lT,
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queryCacheRegion; 2wB*c9~
} F nXm;k,9*
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publicvoid save(finalObject entity){ K$,<<hl
getHibernateTemplate().save(entity); 2(0%{*m
} E;s_=j1f
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publicvoid persist(finalObject entity){ 6`Y:f[VB
getHibernateTemplate().save(entity); Nv.
} w^
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publicvoid update(finalObject entity){ YR0AI l:L
getHibernateTemplate().update(entity); \ui'~n_t]
} SO *oBA'
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publicvoid delete(finalObject entity){ Q"u2<
getHibernateTemplate().delete(entity); !;(Wm6~*ad
} n@ba>m4{
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publicObject load(finalClass entity, g$#A'Du
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finalSerializable id){ [ !#Dba#
return getHibernateTemplate().load ;z9,c
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(entity, id); LKc p.i
} K/Yeh<_&
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publicObject get(finalClass entity, -ak.wwx\
)#i"hnYpQ
finalSerializable id){
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return getHibernateTemplate().get Z]Udx
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(entity, id); Gr&e]M[ l
} ^_\m@
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publicList findAll(finalClass entity){ F%$ q]J[
return getHibernateTemplate().find("from OqMdm~4B!j
-f ~1Id
" + entity.getName()); eDP&W$s#
} 3GKKC9C6
$rk=#;6]v;
publicList findByNamedQuery(finalString ~E8/m_> rU
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namedQuery){ ./3/3&6
return getHibernateTemplate %pOxt<
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().findByNamedQuery(namedQuery); x?B`p"ifS
} @<$m`^H
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publicList findByNamedQuery(finalString query, W0mvwYON[
n(# yGzq
finalObject parameter){ YU6|/
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return getHibernateTemplate `u_MdB}<x;
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().findByNamedQuery(query, parameter); &E0^Jz
} +RM!j9Rq
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publicList findByNamedQuery(finalString query, $v2t6wS,"
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finalObject[] parameters){ PE6,9i0ee
return getHibernateTemplate /^jl||'H,:
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().findByNamedQuery(query, parameters); EX!`Zejf
} 9pj6`5Zn@6
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publicList find(finalString query){ K@2"n|
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return getHibernateTemplate().find Z-4/xi7
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(query); t+F_/_"B
} ?MSwr_eZH
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publicList find(finalString query, finalObject NQuqM`LSQ
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parameter){ ?RsPAL
return getHibernateTemplate().find f$5pp=s: n
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(query, parameter); pN9U1!|uam
} PU%f`)
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public PaginationSupport findPageByCriteria ~&<vAgy,
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(final DetachedCriteria detachedCriteria){ =(\BM')l
return findPageByCriteria -CFy
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); -~JYfj@
} nvwf!iU6
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public PaginationSupport findPageByCriteria qgfP6W$
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(final DetachedCriteria detachedCriteria, finalint ,gG RCp
! N!pvK;
startIndex){ ^ZS!1%1
return findPageByCriteria X}x\n\Z
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(detachedCriteria, PaginationSupport.PAGESIZE, :/$_eg0A
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startIndex); w 2U302TZ
} z>y#^f)r
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public PaginationSupport findPageByCriteria ,G="wI
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(final DetachedCriteria detachedCriteria, finalint [YODyf}M>\
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pageSize, 88S:E7
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finalint startIndex){ )'RaMo` 4
return(PaginationSupport) R6;#+ 1D
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getHibernateTemplate().execute(new HibernateCallback(){ ]i0=3H2
publicObject doInHibernate w8 UUeF
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(Session session)throws HibernateException { 6:; >id${
Criteria criteria = LCj3{>{/=
.GNyADQp
detachedCriteria.getExecutableCriteria(session); 'PFjZGaKR
int totalCount = q`L)^In"
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((Integer) criteria.setProjection(Projections.rowCount 2T(+VeMQ=
+Q);t,
()).uniqueResult()).intValue(); ns\I Y<Yo
criteria.setProjection M?}:N_9<J
Hsv)]
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(null);
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List items = |xg#Q`O
$$o(
criteria.setFirstResult(startIndex).setMaxResults oq$#wiV"Q
2.MUQ;OX
(pageSize).list(); sSGXd=":
PaginationSupport ps = x6!Q''f7
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new PaginationSupport(items, totalCount, pageSize, A! HJ
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startIndex); #Y
return ps; lP]Y^Gz
} 9xzow,mi
}, true); }KIS_krs
} ]sVWQj
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public List findAllByCriteria(final 7D:rq 8$\
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DetachedCriteria detachedCriteria){ 7(tsmP
return(List) getHibernateTemplate L1(-xNUo_i
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().execute(new HibernateCallback(){ qS!N\p~>
publicObject doInHibernate ~UO}PI`C
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(Session session)throws HibernateException { i+~BVb
Criteria criteria = Tt{z_gU6
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detachedCriteria.getExecutableCriteria(session); ,>kVVpu
return criteria.list(); >.K%W*t
} eQ8t.~5;-
}, true); oxL<\4)WJ
} 8uH8)
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public int getCountByCriteria(final `W~
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DetachedCriteria detachedCriteria){ il!B={
Integer count = (Integer) I{[Z
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getHibernateTemplate().execute(new HibernateCallback(){ lA/-fUA
publicObject doInHibernate ku]?"{Xx
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(Session session)throws HibernateException { $^{#hYq)o
Criteria criteria = y'4Qt.1ukN
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detachedCriteria.getExecutableCriteria(session); @Bhcb.kbq
return },JJ!3
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criteria.setProjection(Projections.rowCount t? 6 et1~
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()).uniqueResult(); =IQ}Y_xr
} BYM6cp+S
}, true); {9V.l.Q
return count.intValue(); 0^o/cSF
} jED.0,+K!
} ;e5PoLc
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用户在web层构造查询条件detachedCriteria,和可选的 *w*>\ZhOm
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 >Q=^X3to
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PaginationSupport的实例ps。
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ps.getItems()得到已分页好的结果集 O |P<s+
ps.getIndexes()得到分页索引的数组 +8N6tw/&
ps.getTotalCount()得到总结果数 !^su=c
ps.getStartIndex()当前分页索引 =VuSi(d;e{
ps.getNextIndex()下一页索引 p5or"tK
ps.getPreviousIndex()上一页索引 M;ADL|
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 R`a~8QVh&5
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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 $B%KkD
Ta?}n^V?;
一下代码重构了。 N2A6C$s
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我把原本我的做法也提供出来供大家讨论吧: *qO)MpG{
Nv36#^Z
首先,为了实现分页查询,我封装了一个Page类:
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java代码: TQ4L~8
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/*Created on 2005-4-14*/ 6 V0Ayxg7
package org.flyware.util.page; JJ?rVq1g
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/** b}0h()v
* @author Joa (
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* f2IH2^)P
*/ #vV]nI<MF.
publicclass Page { _(h=@cv
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/** imply if the page has previous page */ MYy58N
privateboolean hasPrePage; vQi=13Pw
PZ8,E{V
/** imply if the page has next page */ LPt9+sauf1
privateboolean hasNextPage; oHx:["F
")uKDq
/** the number of every page */ Ei @
privateint everyPage; \/3(>g?4
0 x-g0]
/** the total page number */ TxG@#" ^g}
privateint totalPage; ^)>( <6
PtW2S 1?j
/** the number of current page */ m#RJRuZ|2V
privateint currentPage; a#r{FoU{M8
'A:Y&w"r
/** the begin index of the records by the current :\"0jQ.y|
G'/GDN^j
query */ +M
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privateint beginIndex; )x/#sW%)
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/** The default constructor */ X<;.
public Page(){ (y>N\xS9
d[3me{Rs
} G:$kGzhJ
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/** construct the page by everyPage
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* @param everyPage t(*n[7e
* */ %[*-aA
public Page(int everyPage){ 0@zJa;z'
this.everyPage = everyPage; ?(=|!`IoO
} :gwmk9LZ
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/** The whole constructor */ "{D/a7]lC
public Page(boolean hasPrePage, boolean hasNextPage, JL87a^ro
WkA47+DsV
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int everyPage, int totalPage, ~3:hed7:
int currentPage, int beginIndex){ YTefEG]|q
this.hasPrePage = hasPrePage; # `E
this.hasNextPage = hasNextPage; f~mwDkf?L
this.everyPage = everyPage; 6P
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this.totalPage = totalPage; F-|DZ?)k5
this.currentPage = currentPage; LvG$J*
this.beginIndex = beginIndex; % E1r{`p
} Ly2,*\7
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/** 1sj7]G]`k
* @return *b) (-#w3
* Returns the beginIndex. l.pxDMY
*/ ~wW]ntZm
publicint getBeginIndex(){ 2Cp4aTGv#
return beginIndex; GCN-T1HvA2
} Vp]7n!g4l
+-'F]?DN'
/** R|qrK
* @param beginIndex ON\bD?(VY
* The beginIndex to set. $EFS_*<X
*/ ek]JzD~w$
publicvoid setBeginIndex(int beginIndex){ #h=V@Dh
this.beginIndex = beginIndex; HU?1>}4L
} -"nkC
IwnDG;+Ap
/** S,:!H@~B
* @return 1w7tRw
* Returns the currentPage. }kmAUaa,Z
*/ cF15Mm2
publicint getCurrentPage(){ I*a@_EO
return currentPage; #(614-r/
} 45.ks.
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/** QHO n?e
* @param currentPage cN&Ebn
* The currentPage to set. G>vK$W$f N
*/ *$0*5d7
publicvoid setCurrentPage(int currentPage){ n}Z%D-b$
this.currentPage = currentPage; [ ft6xI
} akbB=:M,x
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/** Ql5bjlQdO
* @return o
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* Returns the everyPage. ),N,!15j,
*/ %W D^0U|
publicint getEveryPage(){ Gn
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return everyPage; p)B/(%
} J(#6Cld`c
G;cC!x<
/** O"~[njwkE
* @param everyPage n)5t!
* The everyPage to set. apm%\dN
*/ m^L !_~
publicvoid setEveryPage(int everyPage){ :(US um
this.everyPage = everyPage; e:
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} ~|=D.}#$
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/** cL#-vW<s3
* @return *RS/`a;,
* Returns the hasNextPage. Fya*[)HBo
*/ }'wZ)N@
publicboolean getHasNextPage(){ $Be hU
return hasNextPage; c9 EtUv~
} _$$.5?4
}w4OCN\1
/** )=GPhC/sw
* @param hasNextPage #^VZJ:2=|
* The hasNextPage to set. K.QSt
*/ zl8M<z1`1
publicvoid setHasNextPage(boolean hasNextPage){ i=<;$+tW
this.hasNextPage = hasNextPage; cu>(;=
} }6a}8EyFP
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/** *ilh/Hd>
* @return )I*(yUj
* Returns the hasPrePage. eV}" L:bgJ
*/ 5XX)8gAo
publicboolean getHasPrePage(){ ^*f D
return hasPrePage; }d;2[fR)
} \ejHM}w3,
tm5{h{AM
/** T=YVG@fm?
* @param hasPrePage '9u?lA^9$
* The hasPrePage to set. jA9uB.I,"b
*/ AcuZ?LYzK
publicvoid setHasPrePage(boolean hasPrePage){ ,(q]
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this.hasPrePage = hasPrePage; grE(8M
} 0#TL$?=|
sTP\}
/**
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* @return Returns the totalPage. 2Pm}wD^`
* 5B)&;[
*/ 39O rY
publicint getTotalPage(){ G8vDy1`q6
return totalPage; G 3U[)("
} X[Ufq^fyA
/v9qrZ$$
/** R/"f
* @param totalPage RgV3, z
* The totalPage to set. bj@sci(1?
*/ GFLat
publicvoid setTotalPage(int totalPage){ =$4I}2
this.totalPage = totalPage; f@YdL6&d-
} BhDg\oxZ
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} s1wlO y
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 mWZP.w^-
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个PageUtil,负责对Page对象进行构造: BAXu\a-C_
java代码: (/$-2.@
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/*Created on 2005-4-14*/ 36{OE!,i
package org.flyware.util.page; ;SI (5rS?
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import org.apache.commons.logging.Log; OF`J{`{r
import org.apache.commons.logging.LogFactory; xz0t8`NoN
) ??N]V_U
/** ;MNUT,U
* @author Joa c!
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* fx+_;y
*/ KF#^MEw%
publicclass PageUtil { I1m[M?
@P~%4:!Hr
privatestaticfinal Log logger = LogFactory.getLog ?&9=f\/P
>ye.rRZd`
(PageUtil.class); M`K]g&57hL
mW!n%f
/** <eMqg u
* Use the origin page to create a new page l4i51S"
* @param page GdUsv
* @param totalRecords Wap4:wT
* @return {.k IC@^O
*/ 67&IaDts
publicstatic Page createPage(Page page, int I)1ih
Mj1f;$
totalRecords){ :(ql=+vDb4
return createPage(page.getEveryPage(), xltN-<n7
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page.getCurrentPage(), totalRecords); -h7ssf'u[
} ]QR]#[Tn'
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/** *(5;5r
* the basic page utils not including exception @!oN]0`F;
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H`_
handler
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* @param everyPage Q e+;BE-H
* @param currentPage M2ex
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* @param totalRecords G{6@]72
* @return page Epp>L.?r
*/ FJH>P\+
publicstatic Page createPage(int everyPage, int 7r?,wM
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currentPage, int totalRecords){ kM4z
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everyPage = getEveryPage(everyPage); e@VJ-s
currentPage = getCurrentPage(currentPage); |DW^bv
int beginIndex = getBeginIndex(everyPage, BMO,eQcB
wN'S+4
currentPage); n:40T1:q
int totalPage = getTotalPage(everyPage, ,=C ipL9]
\?v&JmEU
totalRecords); qspGNu
boolean hasNextPage = hasNextPage(currentPage, 6R^F^<<
l-W)?d
totalPage); :I7qw0?
boolean hasPrePage = hasPrePage(currentPage); [r>hKZU2
TJRp/BP
returnnew Page(hasPrePage, hasNextPage, M:OZWYQ
everyPage, totalPage, <-N eusx%
currentPage, 5P #._Em
T_2'=7
beginIndex); 3(J>aQZuI
} vcy1itY
yx`@f8Kr
privatestaticint getEveryPage(int everyPage){ ='D%c^;O8'
return everyPage == 0 ? 10 : everyPage; bE%
Hm!
} 'X+aYF}Ye
Y_faqmZ9]
privatestaticint getCurrentPage(int currentPage){ =>PX~/o
return currentPage == 0 ? 1 : currentPage; W (TTsnnx
} .(Ux1.0C
dEXhn
privatestaticint getBeginIndex(int everyPage, int A4l"^dZc
_:Q^mV=;j
currentPage){ >DY/CcG\P
return(currentPage - 1) * everyPage; Z(RsB_u5
} )x[=}0C
?z M
privatestaticint getTotalPage(int everyPage, int z|AknEE,
E l.eK9L
totalRecords){ anz7ae&P'K
int totalPage = 0; `::j\3B&Y-
B YB9M
if(totalRecords % everyPage == 0) o(v`
totalPage = totalRecords / everyPage; Z{(Gib~{N
else !^L}LtqHI
totalPage = totalRecords / everyPage + 1 ; nUONI+6Z/
Rq(+zL(f
return totalPage; oU3gy[wF;b
} {DvWa|
:.H@tBi*E
privatestaticboolean hasPrePage(int currentPage){ YVRE9
return currentPage == 1 ? false : true; _`QME r?
} ~qb?#IY]`
D.AiqO<z
privatestaticboolean hasNextPage(int currentPage, wMF1HT<*
y'f-4E<
int totalPage){ "AJ>pU3
return currentPage == totalPage || totalPage == `$ bQ8$+Ci
jc6~V$3
0 ? false : true; A+Je?3/.
} Vx0Hq`_14
.O~rAu*K
RToX[R;1E
} 0=`aXb-
z}5'TV=^
0_y&9Te
PK?}hz
D0f7I:i1
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 &e[Lb:Uk)
hhjsg?4uL
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 *X|%H-Q:H`
Dh{P23}
做法如下: 5.0;xz}#y
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 +W>tdxOh
V /OW=WCzN
的信息,和一个结果集List: R'K /\
java代码: ~c1~)QzZ
u_WW
uo
N9 )ERW2`*
/*Created on 2005-6-13*/ /$vX1T
package com.adt.bo; QBoX3w=
@J@bD+Q+0
import java.util.List; #lVSQZO~a
&xlOsr/n
import org.flyware.util.page.Page; d9
8pv%
Ej VB\6,
/** y;9K
* @author Joa NVC$8imip
*/ )[sSCt]
publicclass Result { q|D*H9[ke
;NJM3g0I
private Page page; H~hAm
1nLFtiki
private List content; f'Xz4;
5o(=?dXm4
/** p|*b] 36
* The default constructor @qJv
*/ d<;XQ.Wo7
public Result(){ ~>$(5s2
super(); 10/3 -)+
} !q PUQ+
J_|>rfW
/** wVs |mG"
* The constructor using fields -gS/
* ]}0+7Q
* @param page / dn]`Ge)
* @param content R91u6r#
*/
D3 E!jQ1
public Result(Page page, List content){ n_] OYG>U
this.page = page; |om3* ]7
this.content = content; ~Uz|sQ*G
} :TWHmxch
}S&SL)
/** L/cbq*L
* @return Returns the content. %^E>~
*/ `[1]wV5(5@
publicList getContent(){ [
06B)|s
return content; Ki@8
} Ix5yQgnB}j
0MzHr2?'P
/** 3?/}
* @return Returns the page. |y=D^NTG
*/ #$fFp
public Page getPage(){ *m]%eU(
return page; IPE(
} 55N/[{[
a. 5`Q2
/** ~JT{!wcE}o
* @param content e S
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* The content to set. [K9q+
*/ I3aEg
public void setContent(List content){ _H3cqD
this.content = content; CblL1 q8
} ?,),%JQ
]g+(#x_.?
/** IweQB} d
* @param page "ChBcxvxb:
* The page to set. z?YGE iR/}
*/ T
+4!g|Y
publicvoid setPage(Page page){ Ip1QmP
this.page = page; ;[zx'e?!
} %I=J8$B]f
} Y2D)$
-s!PO;qm
$fvUb_n
cE]kI,Fw,M
K|1^?#n
2. 编写业务逻辑接口,并实现它(UserManager, 4-n.4j|
bKaV]Uy
UserManagerImpl) SO&;]YO
java代码: \)"qN^we
?%0i,p@<
QY fS-
/*Created on 2005-7-15*/ !c`1~a!
package com.adt.service; ]V]o%onW
XF$C)id2p
import net.sf.hibernate.HibernateException; nW%c95E
+1623E
import org.flyware.util.page.Page; &]c9}Ic
dCyQC A[
import com.adt.bo.Result; *:_hOOT+[
6%xl}z]o
/** &\K#UVDyhh
* @author Joa t-Fl"@s
*/ wIiT
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publicinterface UserManager { *ZEs5`x
pV+;/y_
public Result listUser(Page page)throws Yb\36|
:R&tO3_F
HibernateException; 8UZEC-K
JZ7-?
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} nC Z
u60l -
%~[F^
#WG(V%f]
OWkK]O
java代码: t8[:}[Jx
[6tQv<}^
pL-$Np] V
/*Created on 2005-7-15*/ j)5Vv
K\
package com.adt.service.impl; i
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Q&LkST-i
import java.util.List; EkBM>*W
GgYomR:
import net.sf.hibernate.HibernateException; Vqr&)i"b$
eyWwE%
import org.flyware.util.page.Page; 3IxT2@H)
import org.flyware.util.page.PageUtil; ]7O?c=
W2k~N X#@
import com.adt.bo.Result; Glr.)PA
import com.adt.dao.UserDAO; J.d `tiN
import com.adt.exception.ObjectNotFoundException; w?C\YKF7
import com.adt.service.UserManager; PrcM'Q
$p@g#3X`
/** }1P
* @author Joa J5"*OH:f
*/ *$1)&2i
publicclass UserManagerImpl implements UserManager { EKf4f^<
k4P.}SJ?
private UserDAO userDAO; 57}q'84
:[&X*bw[
/** /_|1,x-Kx
* @param userDAO The userDAO to set. T_dd7Ym'8
*/ 8K/lpqw
publicvoid setUserDAO(UserDAO userDAO){ D.e*IP1R
this.userDAO = userDAO; ZjK~s)RC
} 90!Ib~7zH
+A3H#'
/* (non-Javadoc) a*8}~p,
* @see com.adt.service.UserManager#listUser #Grm-W9E
y()( 8L
(org.flyware.util.page.Page) XTJ>y@
*/ vX\e*
v
public Result listUser(Page page)throws GSH{1VS_b
wMoAvA_oS
HibernateException, ObjectNotFoundException { bW]+Og
int totalRecords = userDAO.getUserCount(); +*q@= P,
if(totalRecords == 0) GdU
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throw new ObjectNotFoundException %ab79RS]C
;<A/e
("userNotExist"); 5dk,!Cjg
page = PageUtil.createPage(page, totalRecords); ZJ(!jc$"*%
List users = userDAO.getUserByPage(page); aBnbu
vp
returnnew Result(page, users); ccSS au5N
} $\
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p3o?_ !Z
} _u>>+6,p
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4#w^PM8}
gib]#n1!p
z"#.o^5
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 !)=o,sVA
'Ot[q^,KRG
询,接下来编写UserDAO的代码: `N|CL
3. UserDAO 和 UserDAOImpl: 4;||g@f'[
java代码: rzHa&:Y
Ah6x2(:
=*Xf(mh c
/*Created on 2005-7-15*/ A\)X&vR[6
package com.adt.dao; @UJmbD{
z
sPuLn9G
import java.util.List; \tx/!tA
}nl)*l
import org.flyware.util.page.Page; ~tvoR&{I
~~,<+X:
import net.sf.hibernate.HibernateException; >lmL
P1n@E*~V5
/** _O%p{t'q<
* @author Joa ex458^N_
*/ ]o$/xP
publicinterface UserDAO extends BaseDAO { 1`{ib
G65N:
publicList getUserByName(String name)throws
/GUuu
w)n]}k
HibernateException; 8A .7=C' z
'wrpW#
publicint getUserCount()throws HibernateException; #+0R!Y
>ULp!
publicList getUserByPage(Page page)throws c^IEj1@}'?
(q N(#~
HibernateException; H@'
@xHv
;[ueNP%*y|
} hJsC
\ C,^
4
G[hU4L
ASw|sw
':]a.yA\1
V bOLTc
java代码: RfG$Px '
+hgCk87%#
,r;d {
/*Created on 2005-7-15*/ .~
lt+M9
package com.adt.dao.impl; qI*1+R}
:j<JZs>`R
import java.util.List; ZiYzsn
>r3< O=Z7
import org.flyware.util.page.Page; 5Suc#0y
@0,dyg<$>
import net.sf.hibernate.HibernateException;
a|uZJ*
import net.sf.hibernate.Query; 0K0=Ob^(e
MPN=K|*
import com.adt.dao.UserDAO; 7,UFIHq
W%K8HAP "
/** 4CT9-2UC
* @author Joa z,YUguc|
*/ $i~`vu*
public class UserDAOImpl extends BaseDAOHibernateImpl >[4|6k|\x
.WyX/E$I^!
implements UserDAO { =[os<+
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/* (non-Javadoc) bCUh^#]x
* @see com.adt.dao.UserDAO#getUserByName os^SD&hL
M|e
n>P
(java.lang.String) (Gc`3jJ
*/ =3dbw8I
publicList getUserByName(String name)throws <|Eby!KXR
|S`yXsg
HibernateException { 'xoE
[0!
String querySentence = "FROM user in class @k6}4O?{
?9@Af{b t2
com.adt.po.User WHERE user.name=:name"; \'tz|
Query query = getSession().createQuery $'{`i5XB
vqz#V=J{
(querySentence); -01 1U!
query.setParameter("name", name); t0d '>
return query.list(); {}&f\6OI%
} Z;SG<
R${4Q1
/* (non-Javadoc) *1S.9L
* @see com.adt.dao.UserDAO#getUserCount() x~Ly$A2p
*/ Z)T@`B6
publicint getUserCount()throws HibernateException { ?V:]u3
int count = 0; yi-"hT`
String querySentence = "SELECT count(*) FROM %aE7id>v6
(`.qG
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user in class com.adt.po.User"; G:C6`uiy`
Query query = getSession().createQuery 8kM0
<ZC^H
(querySentence); s1 ^mk]
count = ((Integer)query.iterate().next ! vVjZ
p2DNbY\]
()).intValue(); as|c`4r\O
return count; ;6
6_G Sjz
} }rA+W-7
Z6([/n
/* (non-Javadoc) wp*&&0O!
* @see com.adt.dao.UserDAO#getUserByPage 9iddanQA
+\[![r^P
(org.flyware.util.page.Page) V -4*nV
*/ pMZf!&tM
publicList getUserByPage(Page page)throws $F`<&o
)bXx9,VL
HibernateException { Fif^V
String querySentence = "FROM user in class h)l&K%4;
qb&NS4#
com.adt.po.User"; eTRx 6Fri(
Query query = getSession().createQuery <Bb<?7q$ld
n5*{hi
(querySentence); +IO1ipc4cE
query.setFirstResult(page.getBeginIndex()) <Dj$0g
.setMaxResults(page.getEveryPage()); +6M+hO]
return query.list(); 0H&U=9'YT
} XvkI+c
d7tD|[(J
} o- QG&
]
K!D!b'|bb
Pzm!`F^r}
K9O,7h:x
$aPHl
至此,一个完整的分页程序完成。前台的只需要调用 [gh[F
LXu"rfp
userManager.listUser(page)即可得到一个Page对象和结果集对象 %v+fN?%x,d
u"8 ;fS
的综合体,而传入的参数page对象则可以由前台传入,如果用 ~eV!!38
J
CNRU"I+jU
webwork,甚至可以直接在配置文件中指定。 xAd>",=~
s3_e7D ^H
下面给出一个webwork调用示例: Vkvb=
java代码: :Nj`_2
V3A>Ag+^~
/$Tl#
/*Created on 2005-6-17*/ Sd<@X@iU8D
package com.adt.action.user; Fx[A8G
o=RqegL
import java.util.List; _`X#c-J
2hwXWTSu
import org.apache.commons.logging.Log; "X{aS}
import org.apache.commons.logging.LogFactory; Y0u'@l_[F
import org.flyware.util.page.Page; 7fW=5wc
hr!f:D
import com.adt.bo.Result; n@07$lY@;
import com.adt.service.UserService; T:g4D z*2\
import com.opensymphony.xwork.Action; X!#i@V
ss0'GfP
/**
A?;8%00
* @author Joa [N95.aD
*/ nvs}r%1'5
publicclass ListUser implementsAction{ VkTlPmr
>SxZ9T|%
privatestaticfinal Log logger = LogFactory.getLog m]=oaj@9
iy.%kHC
(ListUser.class); @
Zgl>
ULNAH`{D
private UserService userService; DNW2;i<hsz
Ub'%pU
private Page page; ^`jZKh8)h
#[U9(44,
privateList users; fr'huvc
Hr<C2p^a
/* -wfRR>)d
* (non-Javadoc) @( n^S?(
* 16[-3cJ T
* @see com.opensymphony.xwork.Action#execute() `Ge +(1x
*/ jqX@&}3@
publicString execute()throwsException{ >Z2,^5P{
Result result = userService.listUser(page); Rgfc29(8
page = result.getPage(); pe!dm}!h[
users = result.getContent(); x'M^4{4[
return SUCCESS; y3KcM#[
} ra9cD"/J &
=##s;zj(%
/** 0Y6q$h>4
* @return Returns the page. jr[<i\!
*/ ,\S pjE
public Page getPage(){ 0 .FHdJ<
return page; 1~R$$P11[9
} R*Xu(89
sMz^!RX@
/** 0E?s>-b
* @return Returns the users. )H;pGM:
*/ C?w<$DU
publicList getUsers(){ F%PwIB~cy
return users; .B 85!lCF
} P>{US1t
42V,PH6o
/** X/E7o92\
* @param page && DD
* The page to set. 3qAwBVWa
*/ m1hW<
publicvoid setPage(Page page){ B=Zl&1
this.page = page; V\@jC\-5Vt
} jF38kj3O7
c?!YFm
/** /lS+J(I
* @param users kfqpI
* The users to set. RHwaJ;:)#
*/ =mHkXHE~:
publicvoid setUsers(List users){ E7X!cm/2<
this.users = users; m/YH^N0
} >:F,-cx<
VG<Hw{ c3r
/** k'[ S@+5
* @param userService * MSBjH|
* The userService to set. 0^GbpSW{
*/ ;m@1Ec@*p
publicvoid setUserService(UserService userService){ 2SDh0F
this.userService = userService; ~!nLbK2
} >
$w^%I
} Q;$
9qOF
W NwJM
s;fVnaqG:
eeW' [
ioC@n8_[G
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, ~Na=+}.q_
F . K2
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 $nB-ADRu@
!;o\5x<'$O
么只需要: 24T@N~\g
java代码: QU^/[75Ea0
xab]q$n]k
87QZun%
<?xml version="1.0"?> ="uKWt6n'
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork I?_E,.)[ I
eecw]P_?
1.0//EN" "http://www.opensymphony.com/xwork/xwork- CY*ngi &
EKZ$Q4YE
1.0.dtd"> kCima/+_
8G 0
<xwork> DE*MdfP0
nE/=:{~Ws
<package name="user" extends="webwork- uy/y wm/?=
.A3DFm3 t
interceptors"> gw_|C|!P
p=!#],[
<!-- The default interceptor stack name `9.dgV
aB6Ye/Io
--> 1<xcMn0et
<default-interceptor-ref KxO/]
)46
0Ed
name="myDefaultWebStack"/> rkxW UDl
0o=!j3RjH
<action name="listUser" cu[!D}tVU
5^)?mA
class="com.adt.action.user.ListUser"> # v.L$7O
<param Tr}R`6d$
MKU7fFN.
name="page.everyPage">10</param> u-m %=2
<result Q`H#
fS~
'5'3_vM
name="success">/user/user_list.jsp</result> No:^hY:F8
</action> wA?@v|,dZ
[^<SLTev
</package> !8.En8Z<D-
B{s]juPG
</xwork> '@'B>7C#
($c`s8mp
|2z}Xm5\
{tPnj_|n<
m"n.Dz/S
\CcmePTN#x
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 (nGkZ}p
F[5S(7M
7
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 HtxLMzgz<<
Osnyd+dJY
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 E]NY
(1
GGH;Z WSe
#C4|@7w%
:]'q#$!
d!o.ASL{
我写的一个用于分页的类,用了泛型了,hoho _*Pfp+if
aC`Li^
java代码: }/20%fP
y =R
aJm
NdZ)[f:2
package com.intokr.util; }d_<\
L#n}e7Y9
import java.util.List; H ZPcd_(
L^lS^P
/** Qh^R Ax
* 用于分页的类<br> /mc*Hc8R8
* 可以用于传递查询的结果也可以用于传送查询的参数<br> @8|Gh]\P
* D -6
* @version 0.01 I-,>DLG
* @author cheng pDGT@qJ
*/ Rfht\{N 7
public class Paginator<E> { <KtBv Ip]
privateint count = 0; // 总记录数 h6g:(3t6m
privateint p = 1; // 页编号 H.:9:I[n
privateint num = 20; // 每页的记录数 P@C
c]Z
privateList<E> results = null; // 结果 qYiv
0C]4~F x~
/** `|Ey)@w
* 结果总数 I:F
<vE
*/ %l,4=TQ[m
publicint getCount(){ bhYU5I 9
return count; ha5e(Hj?
} glx2I_y
]oEQ4
publicvoid setCount(int count){ AuAT]`
this.count = count; B%fU'
} k52QaMKa~A
&3I$8v|!?
/** c}%es=@
* 本结果所在的页码,从1开始 Ah (iE
* e8{^f]5
* @return Returns the pageNo. G]-%AO{K
*/ 7%4.b7Q
publicint getP(){ 7,h3V=^)Q
return p; Qwv '<
} 9\AS@SH{^T
wlr Ign%
/** 7H%_sw5S.
* if(p<=0) p=1 ]U[&uymax
* S6GMUaR
* @param p Wab.|\c
*/ 8b7;\C~$p
publicvoid setP(int p){ )!eEO [\d
if(p <= 0) VD/&%O8n
p = 1; Lyr2(^#:
this.p = p; G?<pBMy
} LJWTSf"f?
_dr*`yXi
/** 9:-T@u
* 每页记录数量 0R|K0XH#$
*/ Z(HZB
publicint getNum(){ D-pX<0-y
return num; >!
oF0R_<
} cz#_<8'N
Fj^AWv^/
/** lUHtjr
* if(num<1) num=1 vL$|9|W(
*/ IcFK,y%1
publicvoid setNum(int num){ f>niFPW"
if(num < 1) zmb@*/fK
num = 1; p![&8i@ym
this.num = num; >)^NJ2Fd
} #h N.=~
.!yq@Q|=u
/** BC({ EE~R)
* 获得总页数 DWrbp
*/ ]_u`EvEx6
publicint getPageNum(){ Fg=v6j4W
return(count - 1) / num + 1; sKd)BA0`
} bnr|Y!T}Bi
vLDi ;
/** 43L|QFo
* 获得本页的开始编号,为 (p-1)*num+1 \f"1}f
*/ *S4aF*Qk
publicint getStart(){ TKOP;[1h
return(p - 1) * num + 1; \XS]N_}8>
} RdI};K
lsY `c"NW>
/** ln#\sA?iG
* @return Returns the results. &SmXI5>Bo0
*/ ~^7r?<aKc
publicList<E> getResults(){ JYV\oV{
return results; wAh#
} zQc"bcif5(
S?4KC^Y5
public void setResults(List<E> results){ x:
~d@
this.results = results; a5?A!k\2
} B{aU;{1
Cs4hgb|
public String toString(){ h0Jl_f#Y
StringBuilder buff = new StringBuilder }9CrFTbx;
iyj3QLqE
(); r6t&E%b
buff.append("{"); X NE+(Bt
buff.append("count:").append(count); }0;Sk(B>
buff.append(",p:").append(p); C[8Kl D
buff.append(",nump:").append(num); \Y e%o}.{
buff.append(",results:").append iBoEZEHjw
<hv7s,i
(results); lFfXWNb
buff.append("}"); Dm%%e o
return buff.toString(); s.:r;%a
} aZKXD! 4
c'05{C
} J3B.-XJ+n
VR4%v9[1
y|sma;D