Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 e(5:XHe
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 (P+TOu-y\
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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 jo7`DDb
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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 %gd{u\h^
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。 Q)n6.%V/e
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分页支持类: JlM0]__v
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java代码: #><P28m
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package com.javaeye.common.util; h()Ok9]
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import java.util.List; )\k({S
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publicclass PaginationSupport { v$P<:M M
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publicfinalstaticint PAGESIZE = 30; mMz^I7$
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privateint pageSize = PAGESIZE; ZFJqI
&B3[:nS2
privateList items; ( <Abw{BTm
<hJ%]]
privateint totalCount; _$Wj1h
75^U<Hz-3{
privateint[] indexes = newint[0]; 9{A[n}
[i9.#*
privateint startIndex = 0; R#n!1~ (
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public PaginationSupport(List items, int r?:zKj8/u
nn1T5;
totalCount){ F*0rpQ,*
setPageSize(PAGESIZE); (3_m[N\F
setTotalCount(totalCount); Wubvvm8U
setItems(items); "-WEUz
setStartIndex(0); w;p:4`
} 4YT d
}#b[@3/T
public PaginationSupport(List items, int mmJ$+$JEk
Fm| h3.`V
totalCount, int startIndex){ q
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setPageSize(PAGESIZE); VJ8"Q
setTotalCount(totalCount); ]1^F
setItems(items); "1-gMob
setStartIndex(startIndex); M<%g )jn_
} f4b`*KGf
snH9@!cG8
public PaginationSupport(List items, int fFSQLtm?E
Z [aKic
totalCount, int pageSize, int startIndex){ pZ IDGy=~
setPageSize(pageSize); BDO]-y
setTotalCount(totalCount); \qo}}I>e
setItems(items); 0+iaO"%
setStartIndex(startIndex); iB1+4wa
} "u H VX|`
:/.SrkN(A7
publicList getItems(){ ~8j4IO(
return items; v
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} =B/Ac0Y
03!!# 5iJ
publicvoid setItems(List items){ |})7\o
this.items = items; >l$qE
} 8F;r$i2
%xJ6t5.-
publicint getPageSize(){ <Rno;
return pageSize; Yu`KHvur
} Hy*_4r
o)M=; !
publicvoid setPageSize(int pageSize){ >$g+Gx\v4
this.pageSize = pageSize; =Qf.
} RyN}Gz/YN
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publicint getTotalCount(){ Y\e8oIYu7
return totalCount; _
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} ]9 ArT$
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publicvoid setTotalCount(int totalCount){ "Q[rM1R
if(totalCount > 0){ b}C6/zW
this.totalCount = totalCount; KiaQ^[/q
int count = totalCount / [8Yoz1(smA
z5UY0>+VdS
pageSize; *oW^P~m/
if(totalCount % pageSize > 0) mDG=h6y"V
count++; hb,G'IU
indexes = newint[count]; ,~TV/l<
for(int i = 0; i < count; i++){ 3lw8%QD>
indexes = pageSize * `El)uTnuZ[
n{@^ne4m
i; !e0OGf
} Jq1^}1P
}else{ v!~ ;QO
this.totalCount = 0; G(*7hs
} S+LS!b
} O^_$cq
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publicint[] getIndexes(){ 9P)28\4
return indexes; >X$I:M<L
} Z7Gl^4zn
d$;1%rRj8
publicvoid setIndexes(int[] indexes){ v<Ozr:lL
this.indexes = indexes; Yqz
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} #% 1|$V*:
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publicint getStartIndex(){ #A@d;U%
return startIndex; FL /395 <:
} +Y9n@`
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publicvoid setStartIndex(int startIndex){ h=7eOK]
if(totalCount <= 0) z^YL$
this.startIndex = 0; t#eTn";
elseif(startIndex >= totalCount) s7(I
this.startIndex = indexes A
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[indexes.length - 1]; 8K;wX%_,
elseif(startIndex < 0) )Z.M(P
this.startIndex = 0; _]/&NSk
else{ M6MtE_E
this.startIndex = indexes f:K3 P[|
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[startIndex / pageSize]; "x"y3v'
} h{BO\^6x
} 6tDCaB
_XP3|E;I/
publicint getNextIndex(){ pRTdP/(OQ
int nextIndex = getStartIndex() + Sd\+f6x
b- FJMY
pageSize; 'y<<ce*
if(nextIndex >= totalCount) 3v:c".O2O
return getStartIndex(); J_tI]?jrU
else OM1pyt
return nextIndex; %
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} uTq)Ets3
M?FbBJ`sF
publicint getPreviousIndex(){ `BGU
int previousIndex = getStartIndex() - a=%QckR*
n~e#Y<IP\1
pageSize; /`x)B(b
if(previousIndex < 0) sO;]l"{<
return0; }8\"oA6
else M%#H>X\/
return previousIndex; |TE\ ]
} 6Y-sc*5
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} i(pevu
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抽象业务类 s(3iGuT
java代码: /EXubU73
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/** j1hx{P'
* Created on 2005-7-12 CNRiK;nQ
*/ [ ]LiL;A&
package com.javaeye.common.business; "p[FFg
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import java.io.Serializable; ?->&)oAh
import java.util.List; VdfV5"
pSml+A:
import org.hibernate.Criteria; (qky&}H
import org.hibernate.HibernateException; (9X>E+0E
import org.hibernate.Session; qt
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import org.hibernate.criterion.DetachedCriteria; Wt8=j1>
import org.hibernate.criterion.Projections; ~
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import R/UL4R,)^
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org.springframework.orm.hibernate3.HibernateCallback; ^ 1 P@BRh
import Db5y";T
Om/mpU/U
org.springframework.orm.hibernate3.support.HibernateDaoS cYafQyU
TzW1+DxM5
upport; $ [NC$*N7
ti}g?\VT
import com.javaeye.common.util.PaginationSupport; }K%y'D
hG3p"_L
public abstract class AbstractManager extends /t<C_lLM
9}TQu0
HibernateDaoSupport { a!?&8$^<
z#|#Cq`VG
privateboolean cacheQueries = false; ncy? w
e
aRh1Q=^@(4
privateString queryCacheRegion; 'J=knjAT
CaV>\E)
publicvoid setCacheQueries(boolean #FHyP1uyc
F~Z~OqCS
cacheQueries){
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this.cacheQueries = cacheQueries; Wz^M*=,
} \a|bx4M
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publicvoid setQueryCacheRegion(String e[8AdE
01-n_ $b
queryCacheRegion){ nnm9pnx
this.queryCacheRegion = UJX=lh.o
(fYrb#]!y
queryCacheRegion; a=!I(50
} YV 5kzq
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publicvoid save(finalObject entity){ "
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getHibernateTemplate().save(entity); 9j6
} 52L* :|b
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publicvoid persist(finalObject entity){ ~{O9dEI
getHibernateTemplate().save(entity); O [81nlhS0
} !83N.
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publicvoid update(finalObject entity){ f4k\hUA
getHibernateTemplate().update(entity); c_33.i"I}
} `PY>p!E
u,rieKYF
publicvoid delete(finalObject entity){ o.Jq1$)~y
getHibernateTemplate().delete(entity); [9O,C-Mk
} xzRs;AXOp
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publicObject load(finalClass entity, `iiZ
t#p*{S 3u
finalSerializable id){ eZr}xo@9
return getHibernateTemplate().load l*yh(3~}
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(entity, id); >;;tX3(
} _c W(R,i
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publicObject get(finalClass entity, 9b0M'x'W5
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finalSerializable id){ $)5-}NJf'
return getHibernateTemplate().get 5G-}'-R
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(entity, id); LcA~ a<_
} }#rdMh
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publicList findAll(finalClass entity){ \G}$+
return getHibernateTemplate().find("from DB^"iof
fnUR]5\tc
" + entity.getName()); -UPlQL
} 3]X9 z
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publicList findByNamedQuery(finalString l{{wrU`
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namedQuery){ RRNoX}
return getHibernateTemplate QqC4g]
/cy'% .!
().findByNamedQuery(namedQuery); iuX82z`
} CulU?-[i
% 1+\N
publicList findByNamedQuery(finalString query, iE|qU_2Y
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finalObject parameter){ 8"#Ix1#
return getHibernateTemplate mh#dnxeR
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().findByNamedQuery(query, parameter); &tULSp@J
} q]\bJV^/U
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publicList findByNamedQuery(finalString query, F=29"1 ._
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finalObject[] parameters){ 6PS #Zydb
return getHibernateTemplate e*Gm()Vu,
e$E~@{[1)
().findByNamedQuery(query, parameters); t ._PS3
} M@>EZ
btfjmR<Tp
publicList find(finalString query){ ohdWEU,
return getHibernateTemplate().find K$H>/*&'~
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(query); Dm=Em-ST6
} G n_AXN
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publicList find(finalString query, finalObject uh~/ybR
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parameter){ <&?gpRK
return getHibernateTemplate().find Y}bJN%M
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(query, parameter); +7jr ]kP9
} 0 gyg
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public PaginationSupport findPageByCriteria _)7dy2%{q
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(final DetachedCriteria detachedCriteria){ m\h/D7zg
return findPageByCriteria JeR8Mb
r|XNS>V ,$
(detachedCriteria, PaginationSupport.PAGESIZE, 0); ~=Y<B/
} ICD(#m
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public PaginationSupport findPageByCriteria :%dIX}F
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(final DetachedCriteria detachedCriteria, finalint UC,43 z
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startIndex){ /`3^?zlu"
return findPageByCriteria '8NKrI
1@nGD<,.
(detachedCriteria, PaginationSupport.PAGESIZE, %`%xD>![
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startIndex); |5wuYG
} 1Ftl1uf
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public PaginationSupport findPageByCriteria M-!eL<
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(final DetachedCriteria detachedCriteria, finalint zfE;)K^"
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pageSize, `L(AvSR
finalint startIndex){ y)W.xR
return(PaginationSupport) Ge+&C RhyX
8@)/a
getHibernateTemplate().execute(new HibernateCallback(){ 7@MGs2
publicObject doInHibernate J?XEF@?'G
qy`95^
(Session session)throws HibernateException { zaX!f~;"
Criteria criteria = G
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detachedCriteria.getExecutableCriteria(session); TxhTK5#f
int totalCount = ,w|f*L$
jfyV9)
((Integer) criteria.setProjection(Projections.rowCount zh$[UdY6
[=Wn7cr
()).uniqueResult()).intValue(); p6(n\eg R
criteria.setProjection (Al.hEs'
L&qzX)
(null); #,O<E@E
List items = ;T}#-`O_Im
}Po&6^
criteria.setFirstResult(startIndex).setMaxResults Yn,dM~|Cc
=KwG;25hX
(pageSize).list(); 30Nya$$A=
PaginationSupport ps = slEsSR'J]
]6{G;f$
new PaginationSupport(items, totalCount, pageSize, 29g("(}TK
I"E5XVC);
startIndex); NDhHU#Q9
return ps; WigC'
} ,TD@s$2x
}, true); #F5O>9hA
} ^5biD9>M
o/9(+AA>
public List findAllByCriteria(final Hw34wQX
$4`RJ{ZJw]
DetachedCriteria detachedCriteria){ WlVC0&
return(List) getHibernateTemplate wO!k|7:Z
AigL:4[
().execute(new HibernateCallback(){ M:c^[9)y
publicObject doInHibernate WKZ9i2hcdf
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(Session session)throws HibernateException { 7-+X -Y?
Criteria criteria = "k\W2,q[
rr2'bf<]
detachedCriteria.getExecutableCriteria(session); b1>%%#
return criteria.list(); >R/^|hnJ
} __""!Yz
}, true); vBd^=O
} TuphCu+Oh
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public int getCountByCriteria(final
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U]dz_%CRP
DetachedCriteria detachedCriteria){ 6OMywGI[Z
Integer count = (Integer) $=n|MbFl
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z
getHibernateTemplate().execute(new HibernateCallback(){ \LRno3
publicObject doInHibernate A>^\jIB>
]%(hZZ
(Session session)throws HibernateException { :|oH11y
Criteria criteria = 3|RfX
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detachedCriteria.getExecutableCriteria(session); .eW}@1+[;
return ecA[
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criteria.setProjection(Projections.rowCount G*e/Ft.wf8
`9eE139V='
()).uniqueResult(); \1f$]oS
} .l5y!?
}, true); _ Onsfv
return count.intValue(); aYe,5dK>
} pL>Q'{7s3
} ,;C92XY
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用户在web层构造查询条件detachedCriteria,和可选的 v')Fq[H
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 2}1(j
di`Ql._M
PaginationSupport的实例ps。 oddS~lW
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ps.getItems()得到已分页好的结果集 L~Epd.,Dt
ps.getIndexes()得到分页索引的数组 K9}ppgL'$
ps.getTotalCount()得到总结果数 pox\Gu~.0
ps.getStartIndex()当前分页索引 .Xh ^L
ps.getNextIndex()下一页索引 "$PbpY
ps.getPreviousIndex()上一页索引 ;PI=jp
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' A= x
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 aDR<5_Yb
k&ujr:)5Y5
,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 ( }5k"9Z
{
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一下代码重构了。 5NbI Vz
Fkj\U^G
我把原本我的做法也提供出来供大家讨论吧: +wwpaR`
J`;G9'n2
首先,为了实现分页查询,我封装了一个Page类: ,ju 1:`
java代码: L{Epkay,{
MOP
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/*Created on 2005-4-14*/ PX52a[wNDH
package org.flyware.util.page; "EF:+gi#"
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/** Jz 'm&mu
* @author Joa %I;ej{*c
* J6_Hlt
*/ 8vz9o <I
publicclass Page { ~d?7\:n
#z-6mRB
/** imply if the page has previous page */ Fe%Q8RIh_
privateboolean hasPrePage; `,tv&siSA
R*/%+
/** imply if the page has next page */ 3\|e8(bc
privateboolean hasNextPage; }k7@
X
soA>&b!?
/** the number of every page */ K&<bn22
privateint everyPage; lyfLkBF
"T?%4^:g
/** the total page number */ cIK-VmO
privateint totalPage; 7EOn4I2@[
d%VGfSrKq
/** the number of current page */ W@AZ<(RI:
privateint currentPage; G+ Y`65
:D}xT]
/** the begin index of the records by the current 1[D~Eep
h&L+Qx
query */ }4ijLX>b
privateint beginIndex; E {4/$}
9
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M' "S:
/** The default constructor */ ueZ `+g~gg
public Page(){ 5[]7baO)h1
k4'rDJfB
} .Gh-T{\V'
thOQcOf0$
/** construct the page by everyPage 0XSZ3dY&+
* @param everyPage ;n00kel$
* */ EN` --^
public Page(int everyPage){ QL"fC;xUn,
this.everyPage = everyPage; s{x2RDAt
} &Ph@uZ\
B-|:l7
/** The whole constructor */ Ex^7`-2,B
public Page(boolean hasPrePage, boolean hasNextPage, #JYv1F
%L}9nc%~eP
[?)}0cd0
int everyPage, int totalPage, 6Y)'p
.+g
int currentPage, int beginIndex){ [ahD%UxO5
this.hasPrePage = hasPrePage; uXxyw7\W
this.hasNextPage = hasNextPage; ^F5[2<O/!
this.everyPage = everyPage; aRdk^|}
this.totalPage = totalPage; #,Fk
this.currentPage = currentPage; f}Eoc>n
this.beginIndex = beginIndex; i|*(vH&D.
} XWo:~\
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/** NwIl~FNK
* @return `]_#_
* Returns the beginIndex. VT?JTW
*/ ,m{Zn"?kS
publicint getBeginIndex(){ ]L^X}[SH
return beginIndex; l131^48U
} .8uJ%'$)
j5|PQOK
/** D0v!fF~
* @param beginIndex 0rxlN
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* The beginIndex to set. pjvChl5
*/ P7&a~N$T6W
publicvoid setBeginIndex(int beginIndex){ `8\_ ]w0
this.beginIndex = beginIndex; /P<RYA~
} %L=roqz
_' Xt
/** R4 ;^R
* @return u^s{r`/
* Returns the currentPage. =&U JFu
*/ NYM$0v`0YK
publicint getCurrentPage(){ $fPf/yQmC
return currentPage; vY7C!O/y_k
} _]E"hr6a
0V{-5-.
/** V?kJYf(<
* @param currentPage fCJ:QK!
* The currentPage to set. s+2\uMwf*
*/ J1cD)nM<A
publicvoid setCurrentPage(int currentPage){ XG@_Lcv*
this.currentPage = currentPage; \vT0\1:|i
} 8RVNRV@g%
|F-_YR
/** [a53H$`\5
* @return ZtlF]k:MV
* Returns the everyPage. 67+ K
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*/ P+:FiVj@~
publicint getEveryPage(){ &1ASWllD
return everyPage; kn 5q1^
} m4<8v
usZmf=p-r
/** ,v4Z[ (
* @param everyPage QzT )PtX
* The everyPage to set. ;-~Wfh+
*/ ~QJD.'z
publicvoid setEveryPage(int everyPage){ !sfOde)$
this.everyPage = everyPage; 8E H#IiP
} sycN
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/** 9IIQon
* @return Vz1ro
* Returns the hasNextPage. lj/?P9
*/ i*:lZ eU61
publicboolean getHasNextPage(){ v}Gq.(b
return hasNextPage; r50}j
} >k<.bEx(A
?5K.#>{
/** FTI[YR8?Y
* @param hasNextPage 5JK{dis]k
* The hasNextPage to set. b7E= u0
*/ bU/5ug.
publicvoid setHasNextPage(boolean hasNextPage){ ;eI,1
[_
this.hasNextPage = hasNextPage; K
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} bmr.EB/
L7el5Q!Y=
/** U;Se'*5xv
* @return HDvj{
* Returns the hasPrePage. H^_[nL
*/ H[U$4
%t
publicboolean getHasPrePage(){ !lG5BOJM
return hasPrePage; G#ZU^%$M,
} H2 5Mx>|d
ZMids"Xdf
/** DPw"UY:
* @param hasPrePage ajq [ID
* The hasPrePage to set. 1"RO)&
*/ &~:b&
publicvoid setHasPrePage(boolean hasPrePage){ EjV,&7o)
this.hasPrePage = hasPrePage; iIA5ylf{E
} dms R>Q
..UmbJJ.u
/** tu#VZAPW@
* @return Returns the totalPage. ),v[.9!}:
* /Z';#G,z
*/ dy-m9fc6%
publicint getTotalPage(){ j#$ R.
return totalPage; vQ2kL`@
} AYeA)jk
51W\ %aB
/** l3R`3@
* @param totalPage ;g?oU"Y M
* The totalPage to set. dX-{75o5P
*/ {1li3K&0s
publicvoid setTotalPage(int totalPage){ ><}FyK4C
this.totalPage = totalPage; &?f{.
} &%+}bt5
0(VAmb%{
} oFB~)}f<v
V%g$LrLVe
1q0DOf]!T
RJYuyB
fdc
?`4
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 'e^,#L_!o
y/k6gl[`
个PageUtil,负责对Page对象进行构造: IeLG/ fB
java代码: "toyfZq@
Q#Q]xJH
N`1:U
4}
/*Created on 2005-4-14*/ 2>p K
package org.flyware.util.page; %W~Kx_
L}UJ`U
import org.apache.commons.logging.Log; PVH^yWi
n
import org.apache.commons.logging.LogFactory; S;sggeP7,
B!0o6)u'
/** >&6pBtC_
* @author Joa [tGAo/
* D^yZ!}Kl
*/ -'BC*fV r
publicclass PageUtil { 0ubT/
_W'>?e0i
privatestaticfinal Log logger = LogFactory.getLog CMB:%
`% k9@k.
(PageUtil.class); 6*8"?S'
J@PwN^`
/** ~CIA6&
* Use the origin page to create a new page wvBx]$SC
* @param page CE]0OY
* @param totalRecords :akEl7/&
* @return 6Qnerd%Ec
*/ ukHSHsR
publicstatic Page createPage(Page page, int pp@Jndlg
4*'5EBa1
totalRecords){ .lAqD-
return createPage(page.getEveryPage(),
_+[;NBz
k FE2Vv4.
page.getCurrentPage(), totalRecords); uCO-f<b
} <aR9,:
u>o<ua
p
/** s\y+ xa:
* the basic page utils not including exception Z
6KM%R
LsH&`G^<
handler A]L;LkEM
* @param everyPage }tA77Cm)45
* @param currentPage j hf%ze
* @param totalRecords 1"?3l`i
* @return page Sm(X/P=z
*/ )'3(=F$+l
publicstatic Page createPage(int everyPage, int K>iM6Uv
qp3J/(F
currentPage, int totalRecords){ !)gTS5Rh:
everyPage = getEveryPage(everyPage); B64L>7\>`
currentPage = getCurrentPage(currentPage); ,<R/jHZP9
int beginIndex = getBeginIndex(everyPage, 0NrUB
C1&~Y.6m
currentPage); DuX7
int totalPage = getTotalPage(everyPage, {`?C5<r
*'4+kj7>
totalRecords); %EkV-%o*
boolean hasNextPage = hasNextPage(currentPage, pxP,cS
]D_"tQ?i
totalPage); qn)
VKx=
boolean hasPrePage = hasPrePage(currentPage); |s[kY
2yZ/'}Mw
returnnew Page(hasPrePage, hasNextPage, OXcQMVa
6
everyPage, totalPage, Dx`-Kg_p
currentPage, 8g0By;h;
g}
\$9
beginIndex); S.&=>
} =j#1HI=Fe
[&12`!;j
privatestaticint getEveryPage(int everyPage){ l2H-E&'=
return everyPage == 0 ? 10 : everyPage; C".nB12
} hM$K?t
`/?XvF\
privatestaticint getCurrentPage(int currentPage){ +g/TDwyVH
return currentPage == 0 ? 1 : currentPage; JLgk?
} !SRElb A;i
)y>o;^5'
privatestaticint getBeginIndex(int everyPage, int qQK0s*^W
=nPIGI72VO
currentPage){ Mh
[TZfV
return(currentPage - 1) * everyPage; IIrh|>d_7
} ?pSb,kN}'
eaLR-+vEB
privatestaticint getTotalPage(int everyPage, int U8TH} 9Q
tg =ClZ-
totalRecords){ Y' K+O
int totalPage = 0; t8SvU
pFE&`T@ <
if(totalRecords % everyPage == 0) /zxLnT;
5
totalPage = totalRecords / everyPage; dJyf.VJ
else X*f#S:kiNU
totalPage = totalRecords / everyPage + 1 ; 6zv-nMZc
6&,n\EXF
return totalPage; me-Tv7WL
} 1^&qlnqH
A"|y<
privatestaticboolean hasPrePage(int currentPage){ {2jetX`@h
return currentPage == 1 ? false : true; <X@XbM
} c%|K
x
Jv_KZDOdk
privatestaticboolean hasNextPage(int currentPage, 'Mp8!9=&
E|R^tETb
int totalPage){ 8{DZew /
return currentPage == totalPage || totalPage == ;rwjqUDBz
>
mI1wV[
0 ? false : true; dL{zU4iUR
} v9?hcJ=
R"@J*\;$T
H}v.0R
} ]x)^/d
$ glt%a
>fZ N?>`
Ek' ~i
|5J'`1W
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。 GxH]
o8<0#W@S
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 ,q9nHZG^
)9F o
做法如下: o>Fc.$ngZ
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 RWyDX_z#<
O5rHN;\_
的信息,和一个结果集List: VycCuq&M
java代码: Q=B>Q
4Js2/s
RbOEXH*]
/*Created on 2005-6-13*/ cV;<!f+
package com.adt.bo; VTS7K2lBvX
9, A(|g
import java.util.List; =*paa
+M )ep\j
import org.flyware.util.page.Page; (L`7-6e(Ab
Kjw==5)}
/** Myj5qh
* @author Joa 5(9SIj^O
*/ C8^h`B9z&I
publicclass Result { r'|V z*/h
d6(R-k#B
private Page page; kmNa),`{s
^Om0~)"q
private List content; PhUG}94
uGXN ciEp`
/** =2Vs))>Y
* The default constructor mGZJ$ |
*/ hk5[ N=
public Result(){ pJg'$iR!/
super(); N@qP}/}8
} <@F.qMl
bQ%6z}r
/** \,n|V3#G
* The constructor using fields T[?wbYfW
* Uz4!O
* @param page ~wejy3|@0
* @param content Gy;>.:n
*/ ?"hrCEHV{9
public Result(Page page, List content){ Z--A:D>
this.page = page; d+caGpaR
this.content = content; kdgU1T@y.
} 0f_+h %%=
]n \Qa
/** \C{Dui)F
* @return Returns the content. 7dm:L'0
*/ _DDknQP
publicList getContent(){ c[IT?6J4
return content; `s )-
lI
} kv!QO^;^Y
ul@swp
/** f6of8BOg
* @return Returns the page. b(E}W2-t
*/ @PQ%
xcOC7
public Page getPage(){ Os90fR
return page; o[
Je
} lRk)
g)3HVAT
/** ,H)v+lI
* @param content k^H&IS!
* The content to set. thU9s%,
*/ =00c1v
public void setContent(List content){ ^y,Ex;6o
this.content = content; Za110oF
} ~M c'~:{O
S^8C\ E
/** VYR<x QA
* @param page 0I v(ioB=
* The page to set. .S_7R/2(?
*/ VxP cC+
publicvoid setPage(Page page){ t6,bA1*5y
this.page = page; O|} p=ny
} ShIJ6LZ
} ?5IF;vk
o){\qhLp
xCQLfXK7
{`ghX%M(l
YAdk3y~pL
2. 编写业务逻辑接口,并实现它(UserManager, /g`!Zn8a
& FpoMW
UserManagerImpl) f0|wN\
java代码: ?~:4O}5Ax
GXnrVI
;],Js1m
/*Created on 2005-7-15*/ gX%"Ki7.
package com.adt.service; 6(1S_b=a
0X<U.Sxn
import net.sf.hibernate.HibernateException; d}w}VL8l
3a\De(;
import org.flyware.util.page.Page; u*S-Pji,x
|Wg!>g!
import com.adt.bo.Result; E]P7u"1
2JhE`EVH
/** X
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* @author Joa w7%.EA{N
*/ 1RgERj
publicinterface UserManager { {y%|Io`P
'>^!a!<G
public Result listUser(Page page)throws !jTxMf
%Q080Ltet
HibernateException; ?8/T#ox
*UZd!a)
} <\'aUfF v
QPyHos`
*'n L[]
.WVIdVO7
3Fg{?C_l
java代码: wVmQE
E)iX`Xq|0{
xG1(vn83gq
/*Created on 2005-7-15*/ (
}RJW:
package com.adt.service.impl; 3+/^
u- }@^Y$M
import java.util.List; Bfu/w
q&kG>
import net.sf.hibernate.HibernateException; eyzXHS*s;L
i )!+`w*Y
import org.flyware.util.page.Page; 0aqq*e'c
import org.flyware.util.page.PageUtil; YD,<]q%
0JXXJ:d B
import com.adt.bo.Result; ,ll<0Atg
import com.adt.dao.UserDAO; @b9qBJfQ
import com.adt.exception.ObjectNotFoundException; 7NMy1'-q
import com.adt.service.UserManager; 3(,c^F
bs_< UE
/** ;r BbLM`
* @author Joa FmhT^
*/ s>I~%+V.?:
publicclass UserManagerImpl implements UserManager { W) ?s''WE;
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private UserDAO userDAO; n#S?fsQN
{rzvZ0-j}
/** "H\R*\-0
* @param userDAO The userDAO to set.
<64#J9T^
*/ _&RGhA
publicvoid setUserDAO(UserDAO userDAO){ O&
1z-
this.userDAO = userDAO; w&>*4=^a
} j6dlAe
wD92Ava
/* (non-Javadoc) r@c!M|m@
* @see com.adt.service.UserManager#listUser +TC##}Zmb
Hbl&)!I
(org.flyware.util.page.Page) yS.)l
*/ C'6c,
public Result listUser(Page page)throws e8 c.&j3m
bHg 0,N
HibernateException, ObjectNotFoundException { { ^Rr:+
int totalRecords = userDAO.getUserCount(); %x8vvcO^t
if(totalRecords == 0) |,T"_R_K
throw new ObjectNotFoundException ujLje:Yc
.umN>/o[
("userNotExist"); XzB3Xs?W2
page = PageUtil.createPage(page, totalRecords); ]zz%gZz
List users = userDAO.getUserByPage(page); )Vo%}g?6!
returnnew Result(page, users); ul{D)zm\D
} &],O\TAul
>?jmeD3u
} D^S"6v"z
(@NW2
' L-h2
kvN<o-B
Xb@dQRVX
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 +bk+0k9k5
xD9ZL
询,接下来编写UserDAO的代码: 7[1VFc#tf
3. UserDAO 和 UserDAOImpl: ybv]wBpM:
java代码: >@EwfM4[e
}_D{|!!!T
nT7]PhJ
/*Created on 2005-7-15*/ j>3Fwg9V
package com.adt.dao; bsc#Oq]
[W99}bi$
import java.util.List; \j4!dOGZ
d*$x|B|V
import org.flyware.util.page.Page; @QDUz>_y
SC--jhDZ
import net.sf.hibernate.HibernateException; >#y1(\e
8l<~zIoO
/** ;?Q0mXr
* @author Joa f\z9?Z(~
*/ F(`Q62o@
publicinterface UserDAO extends BaseDAO { 65GC7 >[
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publicList getUserByName(String name)throws (!a\23
jGYl*EBx
HibernateException; v}<z_i5/C.
y\:,.cZ+TQ
publicint getUserCount()throws HibernateException; p7L6~IN
Jw^h<z/Ux
publicList getUserByPage(Page page)throws |!J_3*6$>*
4'.]-u
HibernateException; -|P7e
p
~)\!
} KVHK~Y-G
1pqYB]*u_
X*a7`aL
*-'`Ea
oJZ0{^
java代码: 0ke1KKy/d
#fFD|q
qnzNJ_ `R
/*Created on 2005-7-15*/ Q'[~$~&`
package com.adt.dao.impl; ?sxf_0*
w$`u_P|@E:
import java.util.List; I.o3Old
&-x/c\jz
import org.flyware.util.page.Page; D"K!ELGW
u@aM8Na
import net.sf.hibernate.HibernateException; Q;@w\_OR
import net.sf.hibernate.Query; HS|x
:I^4ILQCD
import com.adt.dao.UserDAO; v%QCp
<#~n+,
/** R%JEx3)0m
* @author Joa USXPa[
*/ BT(G9Pj;
public class UserDAOImpl extends BaseDAOHibernateImpl hP/uS%X
Y5TBWcGU%
implements UserDAO { (CE2]Nv9")
.yb8<q s
/* (non-Javadoc) s%?<:9
* @see com.adt.dao.UserDAO#getUserByName V{{UsEVO
WX+@<y}%
(java.lang.String) t5QGXj
*/ FYK}AR<=
publicList getUserByName(String name)throws ve4QS P
*T{KpiuP
HibernateException { Q8DKU
String querySentence = "FROM user in class )EG-xo@X
xH-} <7
com.adt.po.User WHERE user.name=:name"; 5;9.&f
Query query = getSession().createQuery )' 2vUt`_7
)Y?E$=M+B
(querySentence); ;8gODj:dO
query.setParameter("name", name); b{W ,wn
return query.list(); 7.C]ZcU
} ^Cg@'R9
}80n5X<9
/* (non-Javadoc) dTVM
!=
* @see com.adt.dao.UserDAO#getUserCount() jw]IpGTt
*/ ,aa
%{
publicint getUserCount()throws HibernateException { 'eoI~*}3WQ
int count = 0; YC}$O2
String querySentence = "SELECT count(*) FROM v=H!Y";
87nsWBe
user in class com.adt.po.User"; sk. rJ
Query query = getSession().createQuery [oH,FSuO!2
z<BwV
/fH}
(querySentence); cH7D@p}
count = ((Integer)query.iterate().next ^9kdd[
J1Y3>40
()).intValue(); NO#^_N`#\
return count; ,0$b8lb;x/
} q5w)i
/h@rLJ)o>
/* (non-Javadoc) q{.~=~
* @see com.adt.dao.UserDAO#getUserByPage %;G!gJeE
yNQ 9~P2
(org.flyware.util.page.Page) N?Ss/by8Sg
*/ Os1y8ui
publicList getUserByPage(Page page)throws S[uHPYhlA
m$$98N
HibernateException { ix}*whW=U
String querySentence = "FROM user in class K9Pw10g'
t{/
EN)J
com.adt.po.User"; p|w;StLy
Query query = getSession().createQuery +'I8COoiv%
.LNqU#a
(querySentence); D%.<}vG
query.setFirstResult(page.getBeginIndex()) 5{6ebq55"
.setMaxResults(page.getEveryPage()); nzu
3BVv
return query.list(); Xgm9>/y
} ;:gx;'dm5
Eb9M;u
} )5bdWJ>l
,#-^
9a_(_g>S
/t?(IcP5
@i:_JOl
至此,一个完整的分页程序完成。前台的只需要调用 or]s
on1mu't_;
userManager.listUser(page)即可得到一个Page对象和结果集对象 K#p&XIY,
FdJC@Y-#uA
的综合体,而传入的参数page对象则可以由前台传入,如果用 ?|Mmz@
k4 %> F
webwork,甚至可以直接在配置文件中指定。 L:EJ+bNG
*'(dcy9
下面给出一个webwork调用示例: x9CI>l
java代码: UJF
}Ye
DSHpM/7
5*>3(U
/*Created on 2005-6-17*/ L9U<E $%#
package com.adt.action.user; XC{(O:EG
}c,}+{q
import java.util.List; AuYi$?8|5
I!Za2?
import org.apache.commons.logging.Log; `P4qEsZE>`
import org.apache.commons.logging.LogFactory; VVje|T^{Z
import org.flyware.util.page.Page; }fs;yPl,
)+9D$m=P;
import com.adt.bo.Result; Lp*T=]C]
import com.adt.service.UserService; G8?<(.pi@
import com.opensymphony.xwork.Action; W.,J'
efP2 C\
/** am05>c9
* @author Joa `\P :rn95;
*/ QX~*aqS3s8
publicclass ListUser implementsAction{ Ic&t_B*i}]
_>:g&pS/
privatestaticfinal Log logger = LogFactory.getLog tdr*>WL
4/U]7Y
(ListUser.class); _.06^5o
49Ue2=PP#
private UserService userService; @kwD$%*0
7"JU)@ U]
private Page page; 6YU2
!x
C5RDP~au
privateList users; uf)W?`e~
L ou4M
/* JnY3]
* (non-Javadoc) AQ
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* ^! ZjK-$A<
* @see com.opensymphony.xwork.Action#execute() cCV"(Oo[H|
*/ {Q(6
.0R
publicString execute()throwsException{ P [nWmY
Result result = userService.listUser(page); .Na>BR\F
page = result.getPage(); NV-9C$<n2!
users = result.getContent(); /9w}[y*E
return SUCCESS; |H_)u
} #CQ>d8&
c)6Y.[).
/** _@prv7e
* @return Returns the page. o>`/,-!
*/ j*:pW;)^
public Page getPage(){ ?s"v0cg+
return page; EShakV
} S s`0;D1
e<^4F%jSK
/** Gj_b GqF8}
* @return Returns the users. usTCn3u
*/ V!<#E)-?<
publicList getUsers(){ l*:p==
return users; S8)awTA9
} .RWBn~b#I
tl^[MLQa
/** &s <
* @param page [sk"2
* The page to set. _gGy(`
*/ ? s ewU9*
publicvoid setPage(Page page){ GKd>AP_
this.page = page; 6~/H#8Kdn
} P*T)/A%4
)eV40l$
M
/** w9PY^U.Y3e
* @param users ::`j@ ]
* The users to set. |B`tRq
*/ ?GC0dN
publicvoid setUsers(List users){ j5)qF1W,
this.users = users; 7=AKQ7BB>b
} vZDQ@\HrC
`cv:p|s
/** 5UM[Iz
* @param userService 5,((JxX$
* The userService to set. H= y-Y_R
*/ Le'\x`B
publicvoid setUserService(UserService userService){ vxt^rBA
this.userService = userService; ,RHHNTB("
} A{o{o++
} v:0i5h&M
Ji[w; [qL
W[m_IY
yN o8R[M
UiEB?X]-l'
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, |#B"j1D,H
7A|jnm
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 4>E2G:
t;1NzI$^
么只需要: ~GeYB6F
java代码: ~<U3KB
t}FMBGo[
+J4t0x
<?xml version="1.0"?> %dU}GYL_
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork /YbL{G
)j}
N9ufTlq
s
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ybG)=0
i=a LC*@
1.0.dtd"> @6!JW(,]\
`+o.w#cl
<xwork> YC_^jRB8n
Vel;t<1
<package name="user" extends="webwork- u@EM,o
{EUH#':
interceptors"> IXN4?=)I
M5V1j(URE
<!-- The default interceptor stack name g3XAs@
!%X`c94
--> D+3Y.r9
<default-interceptor-ref aVYUk7_ <
,H?p9L; qp
name="myDefaultWebStack"/> ;Z_C3/b
eQx"nl3U%
<action name="listUser" #c>MUC(?s:
h<.[U
$,
class="com.adt.action.user.ListUser"> bSghf"aN
<param ,lJ6"J\8.
S8RB0^Q7
name="page.everyPage">10</param> Q ?t
<result dmy-}.pqN
k
I~]u
name="success">/user/user_list.jsp</result> ;"
*`
</action> j#f&!&G5<&
"/?qT;<$)
</package> 0d ->$gb
sriz
b
</xwork> VWv0\:,G
? ^CGJ1
/8>/"Z2S
^gyp-
!
y^\#bpq&\
F/SsiUBS
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 Cpcd`y=IN
0AKwZ'
&H
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 b2e a0
=.hDf<U
注:上面的<param>的配置,还需要webwork和Spring整合的配合。
1}E@lOc
A*~1Uz\t
{UBQ?7.jE
Bed jw =B
]P$DAi
我写的一个用于分页的类,用了泛型了,hoho <\g&%c,
~,68S^nP)H
java代码: CJixK>Y^
~bTae =FP
-<!17jy
package com.intokr.util; 1>VS/H`
p8d n-4
import java.util.List; c$kb0VR
ON0+:`3\
/** Q;/F0JDH
* 用于分页的类<br> Ch9!AUiR
* 可以用于传递查询的结果也可以用于传送查询的参数<br> Sp,Q,Q4
* %i>e
* @version 0.01 |S:!+[
* @author cheng xPup?oP >
*/ -0da"AB
public class Paginator<E> { oB
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privateint count = 0; // 总记录数 MK"
privateint p = 1; // 页编号 \_AEuz3
F
privateint num = 20; // 每页的记录数 &AcFa<U
privateList<E> results = null; // 结果 #L:P
R>
"q^'5p]
/** &vX!7Y
* 结果总数 V )k, 9=
*/ y32++b!
publicint getCount(){ MW~B[%/
return count; (mIJI,[xn
} lp-Zx[#`}C
m%c0#=D
publicvoid setCount(int count){ F}(QKO*
this.count = count; aiZo{j<6
} 0"psKf'
@1?]$?u&
/** [Cqqjv;_
* 本结果所在的页码,从1开始 |p -R9A*>h
* OsL%SKs|
* @return Returns the pageNo. rHgdvDc
*/ ` ]P5,
publicint getP(){ $>ZP%~O
return p; s.^9HuM
} hdtnC29$
KzX
,n_`an
/** E(!6n= qR
* if(p<=0) p=1 <yI,cM<c
* !LIfeL.4h
* @param p xY'qm8V
*/ CEuk1$
publicvoid setP(int p){ (F[/~~
if(p <= 0) O+p-1 C$\
p = 1; A1QI4.K
this.p = p; 3E}NiD\V}
} j8Q5d`
u] U)d$|
/** 9jR[:[
* 每页记录数量 aXbNDj
][
*/ B UQn+;be
publicint getNum(){ W0MnGzZ
return num; mH*@d"
} 2Uv3_i<
iSr`fQw#
/** Ivt} o_b*
* if(num<1) num=1 CLY6 YB' R
*/ afF+*\xXN
publicvoid setNum(int num){ Wx?&igh
if(num < 1) Cld<D5\|f+
num = 1; ::OFW@dS
this.num = num; *V6QBe
} x`+
l#
AuDR |;i
/** w"a 9'r
* 获得总页数 L;S*.Ol>
*/ 4l
ZJb
publicint getPageNum(){ HKiVEg
return(count - 1) / num + 1; )'!ml
} kV\-%:-
Ue3B+k9w
/** ?S@R~y0K
* 获得本页的开始编号,为 (p-1)*num+1 } }f_
*/ `Ixs7{&jU
publicint getStart(){ #K#Mv/
return(p - 1) * num + 1; `xX4!^0Hm
} Xvu)
P
0Efh?oZ
/** Y$x"4=~
* @return Returns the results. R] Disljq
*/ KIKq9 *
publicList<E> getResults(){ nEd
M_JPv
return results; u*26>.
} ]CIQq1iY
L8:]`MQ0
public void setResults(List<E> results){ chO'Q+pw
this.results = results; hg&w=l
} Q)G!Y
(g\
~Un64M?
public String toString(){ Kunle~Ro
StringBuilder buff = new StringBuilder &$m=^
J&63Z
(); }2Cd1RnS
buff.append("{"); x[PEn
buff.append("count:").append(count); q8?=*1g
buff.append(",p:").append(p); ,TF<y#wed
buff.append(",nump:").append(num); #u8*CA9
buff.append(",results:").append 0):uF_t<
Sf'i{xye
(results);
$-$5ta{s
buff.append("}"); v~V;+S=gz
return buff.toString(); X:G&5
} [_
M6/
-_2Dy1
} dd\bI_
.'5'0lR5
8Wdkztp/S