Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 <_S>- ;by
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 >Jl(9)e
Ix;9D'^}
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 W?5u O
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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 f_*Bd.@
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。 8\+Q*7~@i
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分页支持类: e5!LbsJv
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java代码: i )Hjmf3
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package com.javaeye.common.util; Jl-Lz03YG
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import java.util.List; l .8@F
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publicclass PaginationSupport { wzr3y}fCe
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publicfinalstaticint PAGESIZE = 30; p#VA-RSUQ|
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privateint pageSize = PAGESIZE; >a@c5
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privateList items; <q
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privateint totalCount; Gz]p2KBg
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privateint[] indexes = newint[0]; c~B[<.Qj
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privateint startIndex = 0; j4v.8;
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public PaginationSupport(List items, int 9o|=n'o
9sQ4
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totalCount){ v !~lVv&
setPageSize(PAGESIZE); oUMY?[Wp
setTotalCount(totalCount); O@@=ZyYwc
setItems(items); sx ;7
setStartIndex(0); G@Z,Hbgm
} N`FgjnQ`
prf
public PaginationSupport(List items, int R<}n?f\#JZ
01n5]^.p
totalCount, int startIndex){ +Ar=89
setPageSize(PAGESIZE); a#iJXI
setTotalCount(totalCount); 'eNcQJh
setItems(items); Zrtyai{8l
setStartIndex(startIndex); -^m]Tb<u
} 29(s^#e8A
q[l!kC+Eh
public PaginationSupport(List items, int H pHXt78
FSaCbs(
totalCount, int pageSize, int startIndex){ ,J|8P{ZO
setPageSize(pageSize); VTOZ#*f
setTotalCount(totalCount); {5tb.{
setItems(items); 7!0~sf9A
setStartIndex(startIndex); g5gq{KlU
} iXp*G52
j[zo~Y4z
publicList getItems(){ #HjiE
return items; eyq8wQT
} Q`nsL)J
1+1Z]!nG#!
publicvoid setItems(List items){ _~?N3G
this.items = items; %F'*0<
} 7^}np^[HB
Y`5(F>/RQG
publicint getPageSize(){ | |=q"h3(
return pageSize; &tT*GjPwg;
} W'l
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publicvoid setPageSize(int pageSize){ fiuF!<#;6
this.pageSize = pageSize; $q_e~+SXT
} ZT>?[`Vgc
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publicint getTotalCount(){ `:hEc<_/
return totalCount; 1]wx Ru
} =Ri'Prx&
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publicvoid setTotalCount(int totalCount){ >k gL N
if(totalCount > 0){ |D `r o
this.totalCount = totalCount; J7FCW^-`3
int count = totalCount / ~)';[Ha
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pageSize; fAHK<G4
if(totalCount % pageSize > 0) f>LwsP
count++; l+e L:C!
indexes = newint[count]; 02U5N(s
for(int i = 0; i < count; i++){ *=OU~68)C
indexes = pageSize * iNn]~L1
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i; 1Ner1EKGp
} a1lF8; [
}else{ Z83A1`!.|
this.totalCount = 0; RcQo1
} XUf]gQu3=
} vYT%e:8)q
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publicint[] getIndexes(){ 3z^l
return indexes; X2avo|6e
} k 7 !{p
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publicvoid setIndexes(int[] indexes){ E;[ANy4L
this.indexes = indexes; 35}{dr
} FyZp,uD
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publicint getStartIndex(){ o)_;cCr)q
return startIndex; ?LP&VU1
} wB(A['k
K8,fw-S%
publicvoid setStartIndex(int startIndex){ eK%~`Y
if(totalCount <= 0) }]0f -}
this.startIndex = 0; ]s3U +t?
elseif(startIndex >= totalCount) i
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this.startIndex = indexes h{ s- e.
y/!h.[
[indexes.length - 1]; $tGk,.#j
elseif(startIndex < 0) EAVB:gE
this.startIndex = 0; Tvd=EO
else{ oz!;sj{,D
this.startIndex = indexes x1\a_Kt
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[startIndex / pageSize]; GEr]zMYG[A
}
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} &"^,Ubfcn"
m"MTw@}SJ;
publicint getNextIndex(){ d|UK=B^x
int nextIndex = getStartIndex() + Za+26#g
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pageSize; 0~qnwe[g}
if(nextIndex >= totalCount) %<x2=#0
return getStartIndex(); /\=syl
else L;a>J
return nextIndex; tvH{[e$
} X{SD3j=G#
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publicint getPreviousIndex(){ P{
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int previousIndex = getStartIndex() - 2jQ|4$9j
(+'*_
pageSize; iV8j(HV
if(previousIndex < 0) * A B
return0; dpHK~n j\_
else W~ 6ii\
return previousIndex; MV"aO@
} Y<X,(\iEHP
l`s_Id#
} 9Ra_[1
n !ty\E
L_Q1:nL-0
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抽象业务类 e<_p\LiOS
java代码: ocwh*t)<k
Eeemy*U
vAW+ ,Rfj
/** _KSYt32N
* Created on 2005-7-12 N :E7rtT,M
*/ h(aF>a\Z
package com.javaeye.common.business; VH3j
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import java.io.Serializable; \M4/?<g
import java.util.List; ht8%A 1|
8 Zy`Z
import org.hibernate.Criteria; b<UZDy N~
import org.hibernate.HibernateException; E}S)uI,gn
import org.hibernate.Session; H]a; <V9[
import org.hibernate.criterion.DetachedCriteria; &M$s@FUY
import org.hibernate.criterion.Projections; O9>&E;`5
import (;^VdiJ
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org.springframework.orm.hibernate3.HibernateCallback; kFPZ$8e
import V!=1 !"}OG
AhOvI{
org.springframework.orm.hibernate3.support.HibernateDaoS rSU%!E+|<
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upport; KD]8n]c
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import com.javaeye.common.util.PaginationSupport; Jq1 Zb
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public abstract class AbstractManager extends k8E'wN
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HibernateDaoSupport { uVJ;1H!
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privateboolean cacheQueries = false; ]kC/b^~+m
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privateString queryCacheRegion; j'lfH6_')e
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publicvoid setCacheQueries(boolean $N[-ks2{@
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cacheQueries){ kJP
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this.cacheQueries = cacheQueries; ]Y!$HT7\
} lxTW1kr
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publicvoid setQueryCacheRegion(String Lx&2)
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queryCacheRegion){ )ymd#?wq
this.queryCacheRegion = JCNZtWF
"i$Avm
queryCacheRegion; Yv!%Is
} +.UdEIR";M
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publicvoid save(finalObject entity){ f`@$saFD
getHibernateTemplate().save(entity); ^`
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} XYD}OddO
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publicvoid persist(finalObject entity){ V6'"J
getHibernateTemplate().save(entity); Y=JfV
} (hTe53d<S?
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publicvoid update(finalObject entity){ +,=DUsI}
getHibernateTemplate().update(entity); <_&H<]t%rI
} >
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L1#z'<IO
publicvoid delete(finalObject entity){ ws:@Pe4AF
getHibernateTemplate().delete(entity); pv%UsbY
} F Vkb9(WW
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publicObject load(finalClass entity, $5aRu,
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finalSerializable id){ Kx.I'_Qk
return getHibernateTemplate().load =\Td~>
ks=jv:
(entity, id); %<%ef+*
} nunTTE,iq%
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publicObject get(finalClass entity, h%MjVuLn
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finalSerializable id){ c%Y%c2([
return getHibernateTemplate().get !gv/ jdF
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(entity, id); D2x-Wa
} Y85M$]e,
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publicList findAll(finalClass entity){ f]H[uzsV
return getHibernateTemplate().find("from iTi]D2jC
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" + entity.getName()); gV]]?X&
} 1t{h)fwi
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publicList findByNamedQuery(finalString t-gg,ttnA
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namedQuery){ zSMNk AM
return getHibernateTemplate 1wpT"5B
26|2r
().findByNamedQuery(namedQuery); 4 f/2gI1@B
} zJNiAc
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publicList findByNamedQuery(finalString query, 3uO#/EbS
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finalObject parameter){ 5tI4m#y2
return getHibernateTemplate *Q=ER
U%3d_"{;
().findByNamedQuery(query, parameter); jt-Cy
} P]A>"-k
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publicList findByNamedQuery(finalString query, a]^hcKo4
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finalObject[] parameters){ s"b()JP
return getHibernateTemplate Z_{`$nW
mB&nN+MV
().findByNamedQuery(query, parameters); $@kGbf~k
} +9db1:
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publicList find(finalString query){ NBzyP)2)
return getHibernateTemplate().find $PA=7`\MP/
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(query); |UvM[A|+
} 37'@,*m`
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publicList find(finalString query, finalObject N8.K[ m
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parameter){ iQsv^K!\
return getHibernateTemplate().find W,~s0a!
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(query, parameter); VF1)dd
} 6B
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public PaginationSupport findPageByCriteria 9B&QY 2v
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(final DetachedCriteria detachedCriteria){ Kr $R "
return findPageByCriteria Rh#0EbE2
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 7Yp;B:5@
} ro{q':Z3
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public PaginationSupport findPageByCriteria ]37k\O?vd
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(final DetachedCriteria detachedCriteria, finalint c]:sk[u
'^pA%I2D
startIndex){ KfpDPwP@
return findPageByCriteria OU+oS,
m[S6pqz
(detachedCriteria, PaginationSupport.PAGESIZE, kb<Nuw
u=B_c A}:
startIndex); QF:" >G
} fRKO> /OT
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public PaginationSupport findPageByCriteria -AwR$<q'
@@$=MSN
(final DetachedCriteria detachedCriteria, finalint Rt!G:hy7
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pageSize, /VB n
finalint startIndex){ @7xb/&N
return(PaginationSupport) IxC/X5Mp^q
(,$ H!qKy
getHibernateTemplate().execute(new HibernateCallback(){ seWYY $$
publicObject doInHibernate c`~aiC`l
x]umh{H~
(Session session)throws HibernateException { NQefrof
Criteria criteria = 3vTX2e.w
>o #^r;
detachedCriteria.getExecutableCriteria(session); '@'~_BBZP
int totalCount = \z!*)v/{-
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((Integer) criteria.setProjection(Projections.rowCount )yp+!\
]|g{{PWH
()).uniqueResult()).intValue(); Kl.xe&t@j
criteria.setProjection .Lz\/ OS
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(null); ]Cy1yAv={
List items = ;8m_[gfw
+k]9n*^uz
criteria.setFirstResult(startIndex).setMaxResults AkdONKO8{
Ijq',@jE
(pageSize).list(); H|>dF)%pj
PaginationSupport ps = ?CGbnXZ4Ug
F XJI,(:-
new PaginationSupport(items, totalCount, pageSize, Ys,}L.
XE);oL2xP
startIndex); #UGtYD}"
return ps; a.)Gd]}g
} 5_";EED
}, true); TA;
}
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public List findAllByCriteria(final <(x[Qp/5P
1c);![O
DetachedCriteria detachedCriteria){ De`)`\U
return(List) getHibernateTemplate g2%&/zq/
.Q
FGIAM
().execute(new HibernateCallback(){ VyK]:n<5Q
publicObject doInHibernate *=i|E7Irg
7M#2Tze}
(Session session)throws HibernateException { 5`,qKJ
Criteria criteria = !`S?
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detachedCriteria.getExecutableCriteria(session); ?,e7v.b
return criteria.list(); i/QE)"B"q
} c/.U<
}, true); N}x\Ll
} prE~GO7Z
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public int getCountByCriteria(final }{;m:Iia_
J =o,: 3"
DetachedCriteria detachedCriteria){ N'_,VB
Integer count = (Integer) lot7S XvK
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getHibernateTemplate().execute(new HibernateCallback(){ X8l[B{|
publicObject doInHibernate {IEc{y7?gO
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(Session session)throws HibernateException { e$>.x<
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Criteria criteria = %lPAq
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detachedCriteria.getExecutableCriteria(session); tcOgF:
return Q" BIk
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criteria.setProjection(Projections.rowCount 7eb^^a?
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()).uniqueResult(); /h'V1zL#
} k&|L"N|w
}, true);
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return count.intValue(); B$A`-
} Lf _`8Ux
} `` (D01<
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用户在web层构造查询条件detachedCriteria,和可选的 PY=(|2tb4
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 fiA_6
B6&PYMFK?*
PaginationSupport的实例ps。 >#).3
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ps.getItems()得到已分页好的结果集 d
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ps.getIndexes()得到分页索引的数组 q9rY++Tv
ps.getTotalCount()得到总结果数 "w]
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ps.getStartIndex()当前分页索引 :f (UZmV$
ps.getNextIndex()下一页索引 o= VzVg
ps.getPreviousIndex()上一页索引 d`9%:2qE
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 @]ydWd
4'JuK{/ A7
,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 p^PAbCP'|3
`tKrTq>
一下代码重构了。 }gw
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e=$p(
我把原本我的做法也提供出来供大家讨论吧: Do-~-d4
. 7WNd/WG
首先,为了实现分页查询,我封装了一个Page类: yn=BO`sgW
java代码: C-Y~T;53
1FC'DH!
hUy"XXpr
/*Created on 2005-4-14*/ ( <~
package org.flyware.util.page; ,z A9*
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/** ~)Z{ Yj9)S
* @author Joa 4cC
* [JI>e;l
C:
*/ t[$C r;
publicclass Page { [-}LEH1[p
c:QZ(8d]L
/** imply if the page has previous page */ ]o}g~Xn
privateboolean hasPrePage; hgt@Mb
kY d'6+m
/** imply if the page has next page */ Q+L;k
R
privateboolean hasNextPage; !EO*xxQ
\*] l'>x1
/** the number of every page */ MR$R#
privateint everyPage; 5P=3.Mk
2d1Z;@x
/** the total page number */ b
EB3#uc
privateint totalPage; 1+wmR4o
FDfLPCQm
/** the number of current page */
K?]><z{
privateint currentPage; \VQv
"wid
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/** the begin index of the records by the current SP}!v5.
k@[\C`P
query */ s2SxMFDP
privateint beginIndex; mab921-n
b$7p`Ay
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/** The default constructor */ M8_f{|!&
public Page(){ 6-"@j@l5<
..FEyf
} Ka\ha
uJxT)m!/
/** construct the page by everyPage An0DqjR
* @param everyPage h2k"iO}
* */ ^,-2";2Xh
public Page(int everyPage){ +pcGxje\
this.everyPage = everyPage; r{+P2MPW
} Jd]kg,/
&m{SWV+
/** The whole constructor */ tVI6GXH
public Page(boolean hasPrePage, boolean hasNextPage, 244[a]
%&;
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@k+&89@G
int everyPage, int totalPage, +Tf4SJ
int currentPage, int beginIndex){ %XF>k)
this.hasPrePage = hasPrePage; B/Jz$D
this.hasNextPage = hasNextPage; h7r*5E
this.everyPage = everyPage; }4Q~<2
this.totalPage = totalPage; 3?%?J^/a
this.currentPage = currentPage; ]1Wh3C
this.beginIndex = beginIndex; w.7pD
} 9w)W| 9
oz.#+t%X$b
/** v3p'*81;
* @return ?/@U#Qy
* Returns the beginIndex. }dv$^4
*n
*/ 6&J7=g%G
publicint getBeginIndex(){ t,bQ@x{zVC
return beginIndex; >O;V[H2[
} u;
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9~7s*3zI
/** 0|i3#G_~
* @param beginIndex 1]&FB{l
* The beginIndex to set. +,g3Xqs}X
*/ I$0O4
publicvoid setBeginIndex(int beginIndex){ ?Yf0h_>
this.beginIndex = beginIndex; *J D-|mK
} If>bE!_BO
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/** @PL.7FM<v
* @return M)qb6aD0
* Returns the currentPage. W(#u^,$e[
*/ c1Rn1M,2k
publicint getCurrentPage(){ 'w$jVX/
return currentPage; FF5|qCV/z
} IGnP#@`5]
5 eLm
/** SSQB1c
* @param currentPage V|3^H^\5P
* The currentPage to set. ,=IGqw
*/ 7g7[a/Bts
publicvoid setCurrentPage(int currentPage){ GQH15_
this.currentPage = currentPage; .&i_~?1[N
} %&iodo,EP'
S+ 3lX7
/** u7/]Go44
* @return :pH3M[7
* Returns the everyPage. ]t"X~
*/ %lK/2-
publicint getEveryPage(){ f1$'av
return everyPage; <9 dfbI)
} YB}m1g`
4{lrtNd~K
/** ^TZ`1:oL#
* @param everyPage le|Rhs%Z%
* The everyPage to set. goqm6L^Cu
*/ C~-.zQ$
publicvoid setEveryPage(int everyPage){ ?/}N
this.everyPage = everyPage; I7
= 4%)A
} YD{Ppz
-UoTBvObAm
/** 1/3<u::
* @return _C3O^/<n4V
* Returns the hasNextPage. jO0"`|(]s
*/ Y@y"bjK \
publicboolean getHasNextPage(){ /(u# D[
return hasNextPage; O=5q<7PM.
} ;#?G2AAv
hiKyU!)Hv
/** (fun,(R6"
* @param hasNextPage fZiwuq!_
* The hasNextPage to set. wnU-5r&!]
*/ JfsvK2I
publicvoid setHasNextPage(boolean hasNextPage){ ]iYO}JuX
this.hasNextPage = hasNextPage; ]!X[[w)
} Sby(?yg
3}}8ukq
/** 6_L<&RmLg
* @return ^WkqRs
* Returns the hasPrePage. nB;[;dCz
*/ &+]-e;[
publicboolean getHasPrePage(){ 9e*o$)j_
return hasPrePage; ]++,7Z\AU
} ,m Nd#
d{Cg3v` Rd
/** Oz4vV_a&'
* @param hasPrePage 0j :u.x
* The hasPrePage to set. 6rMXv0)
*/ TWM^5
L :U
publicvoid setHasPrePage(boolean hasPrePage){ Ay6]vU
this.hasPrePage = hasPrePage; {.])'~[U
} =o:1Rc7J
9~J#> C0}
/** N9#5 P!
* @return Returns the totalPage. J9/EJ'My
* Urz9S3#\
*/ Z<iK(?@O
publicint getTotalPage(){ .L~
NX/V
return totalPage; dsn(h5,Q'
} ,<BV5~T.|
SyI\ulmL
/** QM24cm
T
* @param totalPage ?PYZW5
* The totalPage to set. 5\Rg%Ezl
*/ 7~~suQ{F4
publicvoid setTotalPage(int totalPage){ }X6w"
this.totalPage = totalPage; ]$BC f4:
} "/yS HB[
Pm]lr|Q{I
} &
}7+.^
Ss3~X90!*B
B7wzF"
V aoqI
,A5}HRW%
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 i#aKW'
o)GesgxFa5
个PageUtil,负责对Page对象进行构造: +Ks 3
java代码: YwS/O N
&Oc
`|r*
HB,?}S#TP
/*Created on 2005-4-14*/ h$XoR0
package org.flyware.util.page; `-.6;T}2U
D_?dy4\
import org.apache.commons.logging.Log; 82 dmlPwJC
import org.apache.commons.logging.LogFactory; :NL[NbQYt
J|F!$m{
/** ?[|A sw1t
* @author Joa "(iDUl
* au]W*;x
*/ #iQF)x| D
publicclass PageUtil { 'h@&rr@5
oE_*hp+
privatestaticfinal Log logger = LogFactory.getLog v
8EI
Nt;1&dwUb
(PageUtil.class); e)y+]
/#z"c]#
/** 9C8 G(r
* Use the origin page to create a new page $o.;}
* @param page r0@s3/
* @param totalRecords xSqr=^
* @return *&tTiv{^
*/ a)*(**e$*i
publicstatic Page createPage(Page page, int dV{mmHL
H&
$M/`
totalRecords){ 6HPuCP
return createPage(page.getEveryPage(), *+k
yuY J
M~h.MPI
page.getCurrentPage(), totalRecords); nly}ly Q/
} 9f/l"
wwet90_g
/** gi>W&6
* the basic page utils not including exception 0e07pF/!
IEd?-L
handler F-F1^$]k
* @param everyPage H]W'mm
* @param currentPage Ct^=j@g
* @param totalRecords )H`V\H[0P
* @return page x+TdTe;p
*/ da~_(giD*
publicstatic Page createPage(int everyPage, int G^cMY$?99
&^w"
currentPage, int totalRecords){ m?gGFxo
everyPage = getEveryPage(everyPage); YS@TQ?
currentPage = getCurrentPage(currentPage); *Z\AO'h=Z
int beginIndex = getBeginIndex(everyPage, 0_AIKJrL
HRJ\H-
V
currentPage); #k1IrqUp
int totalPage = getTotalPage(everyPage, @FZ_[CYg
~N/a\%`
totalRecords); *&I
_fAh]
boolean hasNextPage = hasNextPage(currentPage, >K&chg@Hv
.'. bokl/
totalPage); ?p/}eRgi
boolean hasPrePage = hasPrePage(currentPage); h:|BQC
:0ltq><?
returnnew Page(hasPrePage, hasNextPage, ll[&O4.F
everyPage, totalPage, cq 5^7.
currentPage, yJ`{\7Uqg
y>:U&P^
beginIndex); .beqfcj"
} :yE0DS<_
&*E! %57
privatestaticint getEveryPage(int everyPage){ L7n G5i
return everyPage == 0 ? 10 : everyPage; '@
p464
} :xTm-L
(74y2U6
privatestaticint getCurrentPage(int currentPage){ V2xvuDHI
return currentPage == 0 ? 1 : currentPage; BP l% SL
} "LH!Trl@k
jt(GXgm
privatestaticint getBeginIndex(int everyPage, int f`*VNB`
WgG$ r
currentPage){ )#1!%aQ
return(currentPage - 1) * everyPage; 2#00<t\
} 4"3.7.<Q`
}D?qj3?bj
privatestaticint getTotalPage(int everyPage, int SSbx[<E3
S>p0{:zM
totalRecords){ v,8Q9<=O
int totalPage = 0; AC 2kG
_"OE}$C
if(totalRecords % everyPage == 0) DajN1}]
totalPage = totalRecords / everyPage; -/0aGqY
else n(|n=P:o
totalPage = totalRecords / everyPage + 1 ; ZR-64G=L,
UCkV;//.
return totalPage; \{!,a
} LEe{fc?{
3TZ:
privatestaticboolean hasPrePage(int currentPage){ !! )W`
return currentPage == 1 ? false : true; mhOgv\?
} Ud2Tn*QmI
:bi(mX7t
privatestaticboolean hasNextPage(int currentPage, WRA(k
/u_9uJ"-K(
int totalPage){ l]#=I7 6
return currentPage == totalPage || totalPage == 7lA_*t@y
#,#:{&H
0 ? false : true; fBh/$
} Hq,@j{($
tl*h"du^
8h4]<T
} "nb.!OG~(
~R~.D
~)`\j
~'0ZW<X.
)n1[#x^I
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。 F |R7hqf
<2]D3,.g.
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 _ WPt
zL
$uJc/
做法如下: C"mWO Y2]
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 .Pte}pM"v
jN'h/\
的信息,和一个结果集List: L,
#|W
java代码: ^c>Bh[
;"ESN)*|i
]NI
CQ9
/*Created on 2005-6-13*/ !4FOX>|L@
package com.adt.bo; nT+ZSr
D`mr>-Y
import java.util.List; -meY[!"X
/3tErc'
import org.flyware.util.page.Page; Iu~<Y(8^q#
5o>*a>27,A
/** vF pKkS343
* @author Joa 7jQVm{{.
*/ .pdcwd9
publicclass Result { =au!rda
6Z' K1
private Page page; ?G!~&
?8?vBkz~
private List content; c0rU&+:Ry
rnQ_0d
/** X9SOcg3a
* The default constructor DpQWh+WRy
*/ O^ui+44wp
public Result(){ 3 =c#LUA`
super(); Rg\4#9S JF
} n f<I
)8eb(!}7
/** @Tq-3Um
* The constructor using fields Lj#xZ!mQS
* qO8:|q1%;\
* @param page V/#J>-os}W
* @param content afna7TlS
*/ 5 r_Z3/%
public Result(Page page, List content){ 5M~nNm[xJU
this.page = page; vu91"
4Fa
this.content = content; Eu"8IM!%-
} +]( y
E{e
/** @1gURx&2_
* @return Returns the content. \>}#[?y
*/ zS|4@t\__
publicList getContent(){ IbL'Z
return content;
N-&ZaK
} ]jn1T^D'
<6Y;VH^_
/** &Xh> w(u
* @return Returns the page. ^Go,HiB
*/ W2fcY;HZ
public Page getPage(){ =3A4.nW
return page; BBGub?(dR
} +F60_O
`
.boBb<
/** @ <2y+_e
* @param content rPyjr(I"_
* The content to set. iM;Btv[|
*/ GYiL}itD=3
public void setContent(List content){ 3!/J!X3L
this.content = content; $d])>4eQ
} a#% *H
ts@Z5Yw*!
/** 8!3 q:8y8
* @param page OHj>ufwVq
* The page to set. _e;bB?S
*/ *i#N50k*j'
publicvoid setPage(Page page){ p-)@#hE
this.page = page; pX*E(Q)@!
} 3D!7,@&>3
} $ta JVVF
4&%H;Q
\}u/0UF97
(Cq 38~mR
?wv3HN
2. 编写业务逻辑接口,并实现它(UserManager, Vn:v{-i
\9tJ/~
UserManagerImpl) =T26vu
java代码: tjB)-=j[
);iJ9+ V}
;-Os~81o?
/*Created on 2005-7-15*/ );}M"W8
package com.adt.service; y=f.;
a73VDQr I
import net.sf.hibernate.HibernateException; .m8l\h^3
KnA BFH
import org.flyware.util.page.Page; @ NL<v-t
2)\MxvfOh
import com.adt.bo.Result; 4g2`[< S
R@NFpiw
/** Z:>3AJuS_
* @author Joa ~"vS$>+
*/ 'nh2}
publicinterface UserManager { "(p /3qFY
7 kA+F+f
public Result listUser(Page page)throws ~vA8I#.
KU{zzn;g
HibernateException; f{O-\
KehM.c^
} ar,v/l>d4N
SFtcO
(G} }h
gg^iYTpt
N}NKQ]=
java代码: a?GXVQ
&Z!y>k%6
$uFvZ?w&
/*Created on 2005-7-15*/ cr]b #z
package com.adt.service.impl; l/B+k
dMsS OP0E
import java.util.List; Bsg^[~jWJu
F:#5Edo}A
import net.sf.hibernate.HibernateException; "q= ss:(
?SO!INJ
import org.flyware.util.page.Page; 8%YyxoCH
import org.flyware.util.page.PageUtil; M=ag\1S&ZF
"$J5cco
import com.adt.bo.Result; CMbID1M3
import com.adt.dao.UserDAO; |.yS~XFJS
import com.adt.exception.ObjectNotFoundException; _[(EsIqc(F
import com.adt.service.UserManager; G4'Ee5(o
lfCr`[!E
/** ;/wH/!b
* @author Joa 'm|T"Ym~
*/ bo<.pK$
publicclass UserManagerImpl implements UserManager { IgwHC0W
&nVekE:!
private UserDAO userDAO; D4y!l~_,%M
+HWFoK
/** FNOsw\Bo
* @param userDAO The userDAO to set. jck(cc=R
*/ P2`F"
Qsq
publicvoid setUserDAO(UserDAO userDAO){ (;05=DsO
this.userDAO = userDAO; WoB'B|%
} H<q|je}e
:BV $3]y
/* (non-Javadoc)
nVgvn2N/
* @see com.adt.service.UserManager#listUser UY({[?Se
LY)Wwl*wc
(org.flyware.util.page.Page) S *J{
*/ Wtk|}>Pf
public Result listUser(Page page)throws 5%QYe]D
W)]&G}U<
HibernateException, ObjectNotFoundException { p$x>I3C(\
int totalRecords = userDAO.getUserCount(); I8T*_u^_
if(totalRecords == 0) Ah@e9`_r
throw new ObjectNotFoundException VB4V[jraCF
h`O$L_Z
("userNotExist"); '-n
Iy$>
page = PageUtil.createPage(page, totalRecords); *>zOWocxD
List users = userDAO.getUserByPage(page); |&-*&)iD|w
returnnew Result(page, users); eY?OUS
} ZBx,'ph}4
>Je$WE3
} )G, S7A
kCz2uG)l
/y4A?*w 6
"SQyy
NJd4( P
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 gp 11/.
Q7F4OS5b
询,接下来编写UserDAO的代码: HGh)d` 8
3. UserDAO 和 UserDAOImpl: e];IQ|
java代码: |E$q S)y
}W!w
*sB'D+-/
/*Created on 2005-7-15*/ +lFBH(o]X
package com.adt.dao; cp~6\F;c
b%"/8rK
import java.util.List; y,1U]1TP
,|?#+O{
import org.flyware.util.page.Page; x5smJ__/
lB/^
import net.sf.hibernate.HibernateException; ;*FY+jM
|9$C%@8
/** N.]~%)K:{
* @author Joa Yc~l Yz+b
*/ U1/ww-!Z
publicinterface UserDAO extends BaseDAO { jgXr2JQ<
&dj/Dq@
publicList getUserByName(String name)throws Gf.xr%mUZr
nZL!}3@<
HibernateException; ]c'EJu
']c;$wP
publicint getUserCount()throws HibernateException; iK1{SgXrFI
5"!K8
N
publicList getUserByPage(Page page)throws VJW8%s[
@V1FBw9S!@
HibernateException; Ygg(qB1q
yLXIjR
} Xq37:E2
/4+zT?f
('BB9#\t
]w]BKpU=
F2Ny=H&G
java代码: ds+2z=!!e
_(io8zqe{j
|pMP-
/*Created on 2005-7-15*/ ##F$8d)q
package com.adt.dao.impl; mAIl)mq|g
2Z<S^9O9
import java.util.List; S7cD}yx*[
KMfRMc&
import org.flyware.util.page.Page; o@j!J I&
;"9Ks.
import net.sf.hibernate.HibernateException; &+oJPpHi\
import net.sf.hibernate.Query; |na9I6
Sa.nUj{M=
import com.adt.dao.UserDAO; .v+J@Y a
aWLA6A+C&
/** (8o;Cm
* @author Joa uP8 cW([
*/ k`[>Bk%b
public class UserDAOImpl extends BaseDAOHibernateImpl P$AHw;n[R
3&c'3y:b
implements UserDAO { ^:f)XZ
}> C?Zx*
/* (non-Javadoc) t)k;5B`> &
* @see com.adt.dao.UserDAO#getUserByName LSXsq}
5OOXCtIKf
(java.lang.String) ,?%Y*?v
*/ )ytP$,r![S
publicList getUserByName(String name)throws QP!;Gwqr
1{cF/ :o
HibernateException { lSd tw b
String querySentence = "FROM user in class j 7O!uUQQ
fffWvf
com.adt.po.User WHERE user.name=:name"; v!<FeLW
Query query = getSession().createQuery -{d(~XIo
f1o^:}5x
(querySentence); SjJ$Oinc
query.setParameter("name", name); *(i%\
return query.list(); _x!/40^G
} }I`o%GL
*(/b{!~
/* (non-Javadoc) 4{6,Sx
* @see com.adt.dao.UserDAO#getUserCount() YLSDJ$K6
*/ /9P7;1?
publicint getUserCount()throws HibernateException { YxU->Wi]G
int count = 0; \sW>Y#9]
String querySentence = "SELECT count(*) FROM !@ AnwV]
yC|odX#
user in class com.adt.po.User"; w`#9Re
Query query = getSession().createQuery UA0(
cK
k4:=y9`R}$
(querySentence); o(3OChH
count = ((Integer)query.iterate().next LT,zk)5
{ M[iYFg=
()).intValue(); %t:13eM
return count; %,Y^Tp
} R \y
qM;2
S!JLy&@
/* (non-Javadoc) 7eZwpg?K
* @see com.adt.dao.UserDAO#getUserByPage Tn>L?
qCm%};yt
(org.flyware.util.page.Page) md : Wx
*/ DC$> 5FDv
publicList getUserByPage(Page page)throws U}<zn+SI#V
"zFTPL"
HibernateException { R-f('[u
String querySentence = "FROM user in class y{tM|
,|UwZ_.
com.adt.po.User"; $"Ci{iE
Query query = getSession().createQuery oMq:4W,
su8()]|0x
(querySentence); sN1I+X
query.setFirstResult(page.getBeginIndex()) !|"LAr9u
.setMaxResults(page.getEveryPage()); "QtkNy%E
return query.list(); `<R^ZL,
} jgYe\dinM
r6 pz(rCs}
} SvQj'5~<
{qH+S/
k)9
pkPl
T^X um2Ec
2)q$HUIX
至此,一个完整的分页程序完成。前台的只需要调用 +]C|y ,r
U\YzE.G1]S
userManager.listUser(page)即可得到一个Page对象和结果集对象 g9=O<u#
#'y^@90R
的综合体,而传入的参数page对象则可以由前台传入,如果用 !JjNm*F[
\ ERHnh
webwork,甚至可以直接在配置文件中指定。 ]XfROhgP=
R}OjSiS\
下面给出一个webwork调用示例: w~e$ul(IQM
java代码: 6:G::"ew
IU]@%jA_:A
eGbjk~,f'
/*Created on 2005-6-17*/ pr1>:0dg
package com.adt.action.user; (xBWxeL~
k]A$?C0Q<%
import java.util.List; {r?Ly1 5
a
0qDRB
import org.apache.commons.logging.Log; 95tHire
import org.apache.commons.logging.LogFactory; "/\-?YJjw
import org.flyware.util.page.Page; \!r,>P
z'Fu} ho
import com.adt.bo.Result; `ItPTSOi
import com.adt.service.UserService; }/%^;@q ;
import com.opensymphony.xwork.Action; U {sT %G
=l}XKl->
/** DDU)G51>d
* @author Joa $-mwr,i
*/ gJ5|P
.
publicclass ListUser implementsAction{ X]Ma:1+
ItQ3|-^
privatestaticfinal Log logger = LogFactory.getLog B%Z ,Xjq
G5zsId
dS
(ListUser.class); FS6ZPjG)
m' L8z
fX
private UserService userService; *Cx3bg*Gan
tWI4x3&2
private Page page; 9,AHC2kn%
|-vn,zpe
privateList users; f9b[0L
X&|y|
/* /A%31WE&1
* (non-Javadoc) C;eM:v0A[
* roWg~U(S
* @see com.opensymphony.xwork.Action#execute() o~p%ODH
*/ 6^Ax3#q
publicString execute()throwsException{ f}zv@6#&
Result result = userService.listUser(page); ,Je9]XT
page = result.getPage(); Cn8w})B
users = result.getContent(); (>gHfC>(lq
return SUCCESS; 7E)*]7B%
} {
daEKac5
<0^L L
/** X&bnyo P
* @return Returns the page. DzK%$#{<
*/ :g"UG0];
public Page getPage(){ 7D)i]68E
return page; mMtX:
} B ez 7
~HyqHxy
/** 2z=aP!9]
* @return Returns the users. 0HS"Oxx'
*/ >=3ay^(Y2D
publicList getUsers(){ ^/v!hq_#%&
return users; ;,jms~ik
} $@4(Lq1.
:~dI2e\:
/** + |d[q?
* @param page PLDp=T%
* The page to set. p |xMXoa`
*/ Ni)/L(
&
publicvoid setPage(Page page){ g{$F;qbkO
this.page = page; G'
a{;3
} tGh!5EZ6`
HCVMqG!
/** I'T@}{h
* @param users @G>Q(a*,
* The users to set. KZt4 dr
*/ }6^d/nE*T
publicvoid setUsers(List users){ IAa}F!6Q1
this.users = users; !S}4b
} J+20]jI
#[aHKq:?b
/** v6_fF5N/
* @param userService 9)]asY
* The userService to set. ~xP4}gs1
*/ fp2.2 @[
publicvoid setUserService(UserService userService){ I2<t?c:Pn<
this.userService = userService; 0!!z'm3
} >`!Lh`n7_
} (}NKW
r1QLSD]i6
j@+QwZL|
;Jq 7E
c2fbqM~
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, %Ut7%obpi
Y)]x1I
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 6P6Pl&
*#2]`G)
么只需要: 0h",.
java代码: 9H4NvB{
7Eett)4
VygiR|f-
<?xml version="1.0"?> kw Iw=8q~
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ?3{:[*
6YeEr!zt%
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 2wki21oY
)kiC/Y}k
1.0.dtd"> r @
IyK%
^u[n!R\
<xwork> PQFr4EY?i
DU>#eR0G
<package name="user" extends="webwork- iw==q:$
op]HF4
interceptors"> tE]0
#B)D<
MTxe5ob`$Q
<!-- The default interceptor stack name y.'5*08S0
%qf ?_2v
--> C:WXI;*cr
<default-interceptor-ref +)eI8o0#
P,/=c(5\}
name="myDefaultWebStack"/> ndU<,{r
UX& ?^]
<action name="listUser" bzt(;>_8
P5^<c\Mr,Y
class="com.adt.action.user.ListUser"> Pa-p9]gq
<param Lupug"p0
3HP o*~"]
name="page.everyPage">10</param> {x#I&ra
<result 6+hx64 =
2,,t+8"`
name="success">/user/user_list.jsp</result> hs5aIJ
</action> HMymoh$Q
<+wbnnK
</package> Dy[_Ix/Y,
Anu`F%OzB
</xwork> j~@Hj$APa`
Iyf hVk?
R!8 qkG
/ .ddx<
%3r`EIB6
nr t3wqJ
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 r(#]Z
9+o`/lk1
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 .7|kxJq
#o]/&T=N=
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 X!vBD
^+m6lsuA
1>BY:xZr
^mA ^7jB
np#RBy
我写的一个用于分页的类,用了泛型了,hoho &2EimP
k15B5
java代码: iVg3=R)[1
Pl}>
n\ yDMY
package com.intokr.util; zFn-VEJ)
'%2q'LqSA
import java.util.List; `?f Y!5BA
@6N$!Q?
/** ?pF7g$>q
* 用于分页的类<br> .(7end<
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ?7Y6: zo$^
* YFF\m{#
* @version 0.01 6/Pw'4H9$
* @author cheng ah(lH5r
*/ CQ`$' oy?W
public class Paginator<E> { <oc"!c;T
privateint count = 0; // 总记录数 i^2yq&uT(
privateint p = 1; // 页编号 Gidh7x
privateint num = 20; // 每页的记录数 !BocF<U E
privateList<E> results = null; // 结果 nF8|*}w
KG!W,tB
/** f`dQ $Kh
* 结果总数 bCv^za]P6
*/ f""+jc1
publicint getCount(){ cM= ?{W7~
return count; |NsrO8H
} aOj(=s
9F&s9(=\
publicvoid setCount(int count){
c%N8|!e
this.count = count; P}AfXgr
} HX(Z(rcI
m|}};8
/** :UMtknV
* 本结果所在的页码,从1开始 oY#62&wk4
* |N{?LKR
%
* @return Returns the pageNo. zuq7 x7
*/ :slVja$e
publicint getP(){ O$2= Z
return p; X~`<ik{q
} *Z+8L*k97
jI-\~
/** ]Ywj@-*q
* if(p<=0) p=1 SP,#KyWP0)
* UY)e6 Zd
* @param p 9&>)4HNd?
*/ ^,?dk![1Cv
publicvoid setP(int p){ =sR]/XSK
if(p <= 0) QL<uQ`>(
p = 1; &g{b5x{iD
this.p = p; u9.x31^
} E7_)P>aS5
x2^Yvgc-
/** Z`?Z1SBt
* 每页记录数量 WxN@&g(
*/ lO Rym:P
publicint getNum(){ NaR/IsN8%
return num; <rO0t9OH
} @435K'!
_* xjG \!
/** y?t2@f]!XK
* if(num<1) num=1 7lo`)3mB
*/ kiW|h)w_,v
publicvoid setNum(int num){ PWwz<AI+
if(num < 1) *@XJ7G[
num = 1; +x7b9sHJ
this.num = num; k,~I>qg
} V!sT2
<$f7&6B
/** ;W/K7}
* 获得总页数 *K{-J*
*/ zfAkWSY
publicint getPageNum(){ )9^0Qk' ]
return(count - 1) / num + 1; 7rc6
} peA}/Jc
"Y9PS_u(~
/** NA%(ZRSg(
* 获得本页的开始编号,为 (p-1)*num+1 *r
b/BZX{
*/ i|z=q
publicint getStart(){ *1}UK9X;
return(p - 1) * num + 1; ST#OO!
} -P+@n)?T6
BCw5.@HK*
/** 6' 9ITA
* @return Returns the results. 9]ga\>v
*/ v<*ga7'S
publicList<E> getResults(){ d)G'y
return results; -,M*j|
} %n^jho5
Mr5E\~K>s
public void setResults(List<E> results){ $ BEIG@qG
this.results = results; 5 A/[x$q
} ,a:!"Z^f
j k%MP6
public String toString(){ .L,xqd[zC
StringBuilder buff = new StringBuilder H5L~[\
5t
^-s'Ad3
(); kRCuc}:SB
buff.append("{"); UStNUNCq
buff.append("count:").append(count); ]h(}%fk_
buff.append(",p:").append(p); P1<Y7+n
buff.append(",nump:").append(num); lJ+05\pE
buff.append(",results:").append HFJna2B`
;.=ZwM]C
(results); ~Rs_ep'+Q2
buff.append("}"); =hs
!t|(*
return buff.toString(); hAPWEh^
} "bO\Wt#Mf
}y<p_dZI
} Ca: jN0
n*tT<
V3<baxdE