Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 !=.y[Db=
!]uB4
detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 CStNCBZ|\
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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 ]rY9t@
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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 cW0\f5[/
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。 F{ vT^/
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分页支持类: a9NuYYr,h
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java代码: K*Ba;"Ugeg
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package com.javaeye.common.util; Y_y!$jd(N
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import java.util.List; CXoiA"P
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publicclass PaginationSupport { l
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publicfinalstaticint PAGESIZE = 30; DpmAB.
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privateint pageSize = PAGESIZE; ]=-=D9ZS3
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privateList items; 8(K:2
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privateint totalCount; wVf 7<@/y
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privateint[] indexes = newint[0]; MhE".ZRd
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privateint startIndex = 0; F^Jz
Z D"*fr
public PaginationSupport(List items, int o ?05bv
g fAWN
totalCount){ S m=ln)G=
setPageSize(PAGESIZE); \^y~w~g?
setTotalCount(totalCount); AG vhSd7
setItems(items); v:74iB$i/C
setStartIndex(0); RLQ*&[A}
} OMjPC_
hC<E4+5.,
public PaginationSupport(List items, int AtHkz|sl
R|qNyNXo[
totalCount, int startIndex){ z@19gD#8
setPageSize(PAGESIZE); h2mHbe43
setTotalCount(totalCount); \oxf_4X
setItems(items); ShV_8F z
setStartIndex(startIndex); 5 8;OTDR!
} CfrO1i F
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public PaginationSupport(List items, int h0~<(3zC
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totalCount, int pageSize, int startIndex){ CL5^>.}
setPageSize(pageSize); 4PS|
setTotalCount(totalCount); p</t##]3ks
setItems(items); 8kU(>' ^_:
setStartIndex(startIndex); q*4@d)_&
} 'Tqusr>lPY
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publicList getItems(){ `]GL3cIh:
return items; %|JL=E}%|
} V :5aq.o!
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publicvoid setItems(List items){ *tpS6{4=#7
this.items = items; jc:=Pe!E
} 4<1V
0VJHE~Bgi
publicint getPageSize(){ >{Mv+
return pageSize; xgNV0;g,
} #H Jlm1d
@ kv~2m
publicvoid setPageSize(int pageSize){ 0;`FS/[(f
this.pageSize = pageSize; /03Wst
} .sj/Lw}
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publicint getTotalCount(){ 751Qi
return totalCount; 6_yatq5c
} PW"?*~&
NhYUSk ~u
publicvoid setTotalCount(int totalCount){ X[w]aJnAr
if(totalCount > 0){ _RzoXn{1e
this.totalCount = totalCount; Imzh`SI,
int count = totalCount / a ge8I$*`@
jc>B^mqx
pageSize; u0? TMy.%
if(totalCount % pageSize > 0) 0%\fm W j
count++; 4V]xVma
indexes = newint[count]; 16z
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for(int i = 0; i < count; i++){ !_c6 `oW
indexes = pageSize * ' _K`1U
_m
a;b<I/<
i; gLo&~|=L-
} >U4bK^/Bp
}else{ eo!+UFZbY
this.totalCount = 0; 8QKu
} W S9:*YH
} =/ !A
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publicint[] getIndexes(){ ~_ovQ4@
return indexes; Ft :_6T%
} :m'(8s8
Bv*VNfUm
publicvoid setIndexes(int[] indexes){ 67Tu8I/r
this.indexes = indexes; #t# S(A9)
} ecvZwL
qM^y@B2MO
publicint getStartIndex(){ 0f+]I=1\
return startIndex; xTcY&
}
#^-'q`)
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publicvoid setStartIndex(int startIndex){ 4 #lLC-k
if(totalCount <= 0) y^{4}^u-^
this.startIndex = 0; [5b[ztN%
elseif(startIndex >= totalCount) s1%2({wP
this.startIndex = indexes [P)](8nR[
5*B'e{C
[indexes.length - 1]; mkBQTQGT
elseif(startIndex < 0) .rDao]K
this.startIndex = 0; 8|hi2Qeu,c
else{ b3GTsX\2|
this.startIndex = indexes &s\,+d0
^b.fci{1m
[startIndex / pageSize]; D[YdPg@-
} 9(Kff nE^
} iN@|08
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publicint getNextIndex(){ W^H[rX}=
int nextIndex = getStartIndex() + lKRp9isn^
>Mm.MNU
pageSize; zRau/1Y0
if(nextIndex >= totalCount) %uP/v\l
return getStartIndex(); TUp%Cx
else ]@}@G[e#[
return nextIndex; &(x>J:b
} sJg3WN
3VQmo\li
publicint getPreviousIndex(){ hGUQdTNP
int previousIndex = getStartIndex() - un,W{*s8*
O=1#KNS
pageSize; D9r;Ys%
if(previousIndex < 0) 4tapQgj24
return0; q|
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else ]zvOM^l~
return previousIndex; T?-K}PUcQ
} ; Oz
p
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} "MOmJYH
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抽象业务类 4)N~*+~\h
java代码: g-+/zEOUS
;/^O7KM-
j8t_-sU9 i
/** D6FG$SV
* Created on 2005-7-12 !<>`G0
*/ @c,=c+-
package com.javaeye.common.business; @oMl^UYM=
5pE@Ww
import java.io.Serializable; Nn5sD3z#
import java.util.List; Vf(n
@d[)i,d:G
import org.hibernate.Criteria; XToYtdt2
import org.hibernate.HibernateException; <,nd]a
import org.hibernate.Session; E{}eYU
import org.hibernate.criterion.DetachedCriteria; OadGwa\:s
import org.hibernate.criterion.Projections; QVR-`d/
import UWBR5
a'\fS7aE0l
org.springframework.orm.hibernate3.HibernateCallback; "&kXAwe
import t\<*Q3rl-
JG'&anbm
org.springframework.orm.hibernate3.support.HibernateDaoS d8f S79
4wwRNu*
upport; !z?:Y#P3
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import com.javaeye.common.util.PaginationSupport; ?eR^\-e
}e,*'mCC*
public abstract class AbstractManager extends 9kU|?JE
js=w!q0)9
HibernateDaoSupport { *>Zq79TG
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privateboolean cacheQueries = false; [-Mfgw]i
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privateString queryCacheRegion; `q1K%id
ezk:XDi4
publicvoid setCacheQueries(boolean DzvGR)>/
)XD$YI
cacheQueries){ rEZMX2
this.cacheQueries = cacheQueries; r6`KZ TU
} _&F*4t!n_
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publicvoid setQueryCacheRegion(String If. hA}
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queryCacheRegion){ 7ZpU -':
this.queryCacheRegion = e p\a
{UEZ:a
queryCacheRegion; j}DG +M
} p4wXsOQ}
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publicvoid save(finalObject entity){ 6imQjtI
getHibernateTemplate().save(entity); e_CgZ
} y+a]?`2
6rzXM`cs
publicvoid persist(finalObject entity){ 9m_Hm')VG
getHibernateTemplate().save(entity); p< jM%fbZk
} ais"xm<V
;(9q, )
publicvoid update(finalObject entity){ UR.l*+<W7
getHibernateTemplate().update(entity); e@crM'R7Lo
} C+c;UzbD
t[ ^68]
publicvoid delete(finalObject entity){ W-@}q}A
getHibernateTemplate().delete(entity); l8ZzKb-
} UPJ3YpK
3+$~l5LY
publicObject load(finalClass entity, _n_|skG
.
[\S=K|/
finalSerializable id){ c27A)`
return getHibernateTemplate().load @,v.Y6Ge
PaYsn *{})
(entity, id); F:rT.n
} c4n]#((%a
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publicObject get(finalClass entity, Ucz`^}+
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finalSerializable id){ 41jx+
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return getHibernateTemplate().get (Puag*
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(entity, id); -XtDGNHF
} (y!<^Q
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publicList findAll(finalClass entity){ |cCrLa2*-
return getHibernateTemplate().find("from Aaq!i*y
x0_$,Tz@
" + entity.getName()); P mgTTI
} sKI{AHJ?X
3]1uDgfr
publicList findByNamedQuery(finalString W-+~r
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namedQuery){ bjEm=4FI;
return getHibernateTemplate &]Q\@;]Aq
!r*Ogv[
().findByNamedQuery(namedQuery); \sZ!F&a~
} 0(!D1G{ul
h*9s^`9)
publicList findByNamedQuery(finalString query, H"A|Z6y$^
?4,e?S6,[
finalObject parameter){ fB3W} dr
return getHibernateTemplate !4B($]t
VCZ.{MD
().findByNamedQuery(query, parameter); 0WI3m2i
} L<**J\=7M
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publicList findByNamedQuery(finalString query, xr*hmp1
.A`Q!
finalObject[] parameters){ h}o7/p
return getHibernateTemplate #4e Taik
yY$:zc"J
().findByNamedQuery(query, parameters); yH0BNz8V
} 3-5X^!C
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publicList find(finalString query){ b-rgiR$cg
return getHibernateTemplate().find QK3j.Ss
Z;bg;@r|
(query); 5g3D}F>OJ
} 3;6Criq}
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publicList find(finalString query, finalObject z\fmwI
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@
parameter){ \.tnzP
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return getHibernateTemplate().find ^%V^\DK
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(query, parameter); \,i?WgWv
} J`*!U4
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public PaginationSupport findPageByCriteria ,dM}B-
{ ke}W
(final DetachedCriteria detachedCriteria){
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return findPageByCriteria @3hA\3ot^
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); "Y Z B@
} {>E`Zf:
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public PaginationSupport findPageByCriteria wua`e <"
dd +%d
(final DetachedCriteria detachedCriteria, finalint 1 U|IN=
VgHVj)ir
startIndex){ Ne)H*DT
return findPageByCriteria e==}qQ
'<.@a"DnJ
(detachedCriteria, PaginationSupport.PAGESIZE, D.hj9
9b8ZOk'9_
startIndex); #R<ErX)F
} 478gl
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public PaginationSupport findPageByCriteria U&uop$/Cq
#3l&N4/
(final DetachedCriteria detachedCriteria, finalint j~d<n_
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pageSize, ([y 2x.kd
finalint startIndex){ Hvto]~=GQ
return(PaginationSupport) nS8oSs_
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getHibernateTemplate().execute(new HibernateCallback(){ 9 -\.|5;:
publicObject doInHibernate [f9U9.fR
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(Session session)throws HibernateException { aB6F<"L,
Criteria criteria = >8$]g
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detachedCriteria.getExecutableCriteria(session); &>
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int totalCount = Hp2ysU
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((Integer) criteria.setProjection(Projections.rowCount "w#jC~J<W
&jh'B ,
()).uniqueResult()).intValue(); &QaFX,N"
criteria.setProjection Cx.GEY|0
/~?'zr
(null); C 'YL9r-G
List items = 0:Ow$
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criteria.setFirstResult(startIndex).setMaxResults lLq:(zMH
aXAV`%b
(pageSize).list(); 'rZYl Qm
PaginationSupport ps = Cy'0O>v5
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new PaginationSupport(items, totalCount, pageSize, <<,YgRl2
95
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startIndex); +}eGCZra
return ps; rq;Xcc
} ev}lb+pr)_
}, true); hx4X#_)v
} 8CR b6
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public List findAllByCriteria(final _sEkKh8x
>l & N
DetachedCriteria detachedCriteria){ ?U\@?@
return(List) getHibernateTemplate u|v2J/_5Y
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().execute(new HibernateCallback(){ VM
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publicObject doInHibernate s bl>i
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(Session session)throws HibernateException { s<f<:BC
Criteria criteria = 73b(A|kQ@
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detachedCriteria.getExecutableCriteria(session); r5h+_&v,M
return criteria.list(); jea{BhdUr
} ;}iV`)S
}, true); p~/
} ;7jszs.6%
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public int getCountByCriteria(final nH6Ny
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DetachedCriteria detachedCriteria){ Q{s9{
Integer count = (Integer) fwe4f
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getHibernateTemplate().execute(new HibernateCallback(){ op\'T;xIu
publicObject doInHibernate 3#O Rfr(
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(Session session)throws HibernateException { xc4g`Xi
Criteria criteria = _$g2;X >
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detachedCriteria.getExecutableCriteria(session); 4<j)1i=A
return !fwMkws
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criteria.setProjection(Projections.rowCount n};:*N!
v
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()).uniqueResult(); /$w,8pV=
} ,".1![b
}, true); |ia#Elavo
return count.intValue(); nY]5pOF:
} wZ&l6J4L
} WOw( -
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用户在web层构造查询条件detachedCriteria,和可选的 [;?CO<
Pv- i.
startIndex,调用业务bean的相应findByCriteria方法,返回一个 reBAxmt
,;&j*qFi
PaginationSupport的实例ps。 %T~3xQ
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ps.getItems()得到已分页好的结果集 Wu}84W"!.V
ps.getIndexes()得到分页索引的数组 16J"QUuG
ps.getTotalCount()得到总结果数 ><t4 f(d
ps.getStartIndex()当前分页索引 8>\tD
ps.getNextIndex()下一页索引 /0.m|Th'm
ps.getPreviousIndex()上一页索引 A_:CGtv:
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$(3mpQAg
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 tsYBZaH
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 !HV<2q()
z CS.P.$
一下代码重构了。 e-Pn,j
J~}%j.QQ7
我把原本我的做法也提供出来供大家讨论吧: hDn?R}^l{
<5 ?
首先,为了实现分页查询,我封装了一个Page类: G\X}gqe(OJ
java代码: 4p}?QR>tZ
0*=[1tdWY
yi29+T7j4S
/*Created on 2005-4-14*/ UrMEL;@g
package org.flyware.util.page; ]!um}8!}
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/** |~+i=y
* @author Joa Oq`CK f
* f/?uosS
*/ 6Z}8"VJr {
publicclass Page { ,8tk]W[C
ro%Jg
/** imply if the page has previous page */ l;~b:[r
privateboolean hasPrePage; 8q}955Nl
4X}.aZO&b
/** imply if the page has next page */ rf ?\s/#OY
privateboolean hasNextPage; wr) \GJ#>
iImy"$yX{
/** the number of every page */ SsY:gp_
privateint everyPage; eBZ94rA]
s"'ns
/** the total page number */ Rj'Tu0l
privateint totalPage; F|wT']1Y
@mD$Z09~
/** the number of current page */ D8rg:,'6
privateint currentPage; dvW2X
f>!H<4
]
/** the begin index of the records by the current +u[^@>_I0
I2&R+~ktR
query */ }!`_Bz:
privateint beginIndex; x\i+MVR-
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/** The default constructor */ qexnsL
public Page(){ _{
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} +~7x+6E
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/** construct the page by everyPage "Dt:
8Nf^
* @param everyPage ns&3Dh(IVP
* */ x@p1(V.
public Page(int everyPage){ u]766<Z
this.everyPage = everyPage; ]YciLc(
} {0o,2]o!:
YXlaE=9bn
/** The whole constructor */ <K:L.c!
public Page(boolean hasPrePage, boolean hasNextPage, {Qf/.[
9< |nJt
H"; !A=0
int everyPage, int totalPage, 8
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int currentPage, int beginIndex){ \dHdL\f
this.hasPrePage = hasPrePage; sJ>JHv
this.hasNextPage = hasNextPage; .gJv})Vi
this.everyPage = everyPage; Xt%y>'.
this.totalPage = totalPage; qydRmi
this.currentPage = currentPage; P-_2IZiz
this.beginIndex = beginIndex; _qf$dGqc
} p[8H!=`K
_g]h \3
/** = e"RE/q2
* @return z=j,-d%9
* Returns the beginIndex. !q[r_wL
*/ j9r%OZw{
publicint getBeginIndex(){ Q>yO,H|
return beginIndex; [sXnB$
} UfNcI[xr
Njmb{L]Cps
/** :5-t$^R
* @param beginIndex ;39~G T
* The beginIndex to set. +UX~TT:
*/ Swxur+hfH
publicvoid setBeginIndex(int beginIndex){ 9}|t`V"
this.beginIndex = beginIndex; 1]wo
}
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1Xkl.FcFw
/** 2~y<l
* @return 5M?
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* Returns the currentPage. Ge=|RAw3
*/ )~{8C:
publicint getCurrentPage(){ *?x[pqGq
return currentPage; VD90JU]X<
} 9&"wfN N
vWZ?*0^
/** iI$;%uY3g
* @param currentPage k fY0u
* The currentPage to set. \GdsQAF"
*/ w?JM;'<AYQ
publicvoid setCurrentPage(int currentPage){ 87-z=>IU
this.currentPage = currentPage; w gkY\Q
} 5`FPv4
*s%M!YM
/** HXP/2&|JY
* @return u):Nq<X
* Returns the everyPage. FfM,~s<Efz
*/ v@1f,d
publicint getEveryPage(){ {wptOZ
return everyPage; BMH?BRi
} c{{RP6o/j=
[<JY[o=
/** fD#!0^
* @param everyPage bqwn_=.
* The everyPage to set. ^5Ob(FvU
*/ T( CTU/a-,
publicvoid setEveryPage(int everyPage){ Z^t{m!v
this.everyPage = everyPage; 5n1T7-QCL
} r:Ok z
5gZ*
/** | E\ u
* @return l}XnCOIT,
* Returns the hasNextPage. %g7B*AX]
*/ |o#pd\
publicboolean getHasNextPage(){ -uhg7N[3
return hasNextPage; =GL^tAUJ
} 1$nuh@-ys
]?k\ qS
/** =p \eh?^
* @param hasNextPage 6Zmzo,{
* The hasNextPage to set. gCZm7dgo
*/ j|IvDrm#
publicvoid setHasNextPage(boolean hasNextPage){ I^?hVH
this.hasNextPage = hasNextPage; )E}eK-Yu
} la_FZ
T5+
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/** @ 5V3I^
* @return cdv0:+[P
* Returns the hasPrePage. ^o[(F<q
*/ "vo
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publicboolean getHasPrePage(){ w^)_Fk3
return hasPrePage; qFwAzW;"
} K{`3,U2Wx
c{\x<AwO
/** $c];&)7q
* @param hasPrePage kp8kp`S7
* The hasPrePage to set. s>a(#6Q
*/ t}2M8ue(&
publicvoid setHasPrePage(boolean hasPrePage){ r~; TId} #
this.hasPrePage = hasPrePage; DC,]FmWs!+
} uE&2M>2
F>"B7:P1:Q
/** r^ +n06[
* @return Returns the totalPage. U>a~V"5,u
* Yzih-$g
*/ VR vX^w0
publicint getTotalPage(){ S!R:a>\
return totalPage; f= 33+8I
} m8z414o
m$A-'*'
/** C''[[sw'K
* @param totalPage Z]k+dJ[-
* The totalPage to set. `YK%I8
*/ &` weW
publicvoid setTotalPage(int totalPage){ !345
this.totalPage = totalPage; 2VgVn,c
} {3N5Fi7S
FSyeDC^@
} giu8EjzK
jHM}({)-
1w|u
^[~u\
z{G@t0q
i&zJwUr(<
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 ufXU
^Z G 3{>
个PageUtil,负责对Page对象进行构造: g?e-D.pSF
java代码: S3Sn_zqG
<j^"=UN4#
\j~LxV
/*Created on 2005-4-14*/ I#GsEhi
package org.flyware.util.page; \++#adN:K
KL+, [M@ F
import org.apache.commons.logging.Log; i`vgD<}
import org.apache.commons.logging.LogFactory; B{-+1f4
'H)l~L
/** uz@WW!+o
* @author Joa
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* Jkub|w#QH
*/ ?KXgG'!!
publicclass PageUtil { & <Jvaf_=
"jAEZ
privatestaticfinal Log logger = LogFactory.getLog #{Gojg`5O
Y)9]I6n7
(PageUtil.class);
QTuj v<|
m|cT)-
/** tC'@yX
* Use the origin page to create a new page ^|h})OHV
* @param page MDh^ic5
* @param totalRecords #wL8=QTcNC
* @return I,YP{H 4
*/ U\`H0'
publicstatic Page createPage(Page page, int O{44GB3
q
NE(@at
totalRecords){ 2a[_^v $v
return createPage(page.getEveryPage(), 2:D1<z6RQ
b}5hqIy
page.getCurrentPage(), totalRecords); *XSHzoT*
} G~|Z(}H
D4W^{/S
/** r d4\N2- 6
* the basic page utils not including exception @Z%I g
I\oI"\}U
handler %.n 7+
* @param everyPage F/zbb
* @param currentPage F` gQ[
* @param totalRecords `PeWV[?
* @return page 4.0JgX
*/ o 2sOf
publicstatic Page createPage(int everyPage, int Q.]RYv}\
ziBg'
currentPage, int totalRecords){ 7s-ZRb[)1
everyPage = getEveryPage(everyPage); LG3:V'|
currentPage = getCurrentPage(currentPage); fxL0"Ry
int beginIndex = getBeginIndex(everyPage, ZsikI@?
iv]*HE
currentPage); *C n `pfO
int totalPage = getTotalPage(everyPage, *Mr?}_,X*
84$#!=v
totalRecords); 6KzdWT
boolean hasNextPage = hasNextPage(currentPage, 2t7Hu)V
"lJ[H=\
totalPage); )./'`Mx?
boolean hasPrePage = hasPrePage(currentPage); 3gzcpFNqX
v5!G/TZ1
returnnew Page(hasPrePage, hasNextPage, KZ}F1Mr
everyPage, totalPage, <!M ab}
currentPage, %T:7I[f
}v?_.MtS
beginIndex); D/=
AU
}
S9Ka
=2yg:D
privatestaticint getEveryPage(int everyPage){ T2V#
fYCc
return everyPage == 0 ? 10 : everyPage; #`9D,+2iB%
} xX]92Q
}R -azN;
privatestaticint getCurrentPage(int currentPage){ G[=8Ko0U+n
return currentPage == 0 ? 1 : currentPage; dJ0qg_ U&
} yAt,XG3
\.7O0Q{
privatestaticint getBeginIndex(int everyPage, int E5}wR(i,4
l;gj],*
currentPage){ NFQR
return(currentPage - 1) * everyPage; "Lp"o
} =Nj58 l
8+7=yN(
privatestaticint getTotalPage(int everyPage, int 5%E.UjC
47c` ) *Hc
totalRecords){ ^,.G<2Kx&
int totalPage = 0; d=B
DR^/wA
iqj
ZC80
if(totalRecords % everyPage == 0) I3ZbHb-)_,
totalPage = totalRecords / everyPage; >^Zyls
else xe3t_y
totalPage = totalRecords / everyPage + 1 ; "T_OLegdK
"/-T{p;.
return totalPage; TdAHw
@(
} -UM5&R+o
@9!,]n
privatestaticboolean hasPrePage(int currentPage){ !MiH^wP
return currentPage == 1 ? false : true; V\V:uo(C
} >{dj6Wo
mfNYN4Um6
privatestaticboolean hasNextPage(int currentPage, *?#t (Y[
,^_aqH
int totalPage){ p|D-ez8
return currentPage == totalPage || totalPage == `ju r`^S|
{,|J?>{
0 ? false : true; _\P9~w
`
} 3 #zwY
YC
uuj$
|# zznT"
} +I?T|Iin
u$Za hN!
D*oJz3[
\y%:[g}Fvw
@YEdN}es
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 J6H3X;vxQw
sH>Z{xjr
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 /Nh:O
3ee?B~Tun
做法如下: Q\DD^Pbq
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 :W/,V^x}
Wkk=x&
的信息,和一个结果集List: hk O)q|1
java代码: +C{ %pF
[akyCb
z5CWgN
/*Created on 2005-6-13*/ #]yb;L
package com.adt.bo; h%Nbx:vKk
7b2N'^z}
import java.util.List; %0PZZl5b
Hset(-=X
import org.flyware.util.page.Page; H:ar&o#(
3huTT"G
/** bm{L6D E
* @author Joa
4^L+LY
*/ U~SOHfZ%(
publicclass Result { =%:mZ@x'
}@pe`AF^
private Page page; mySm:ToT
*n)3y.s
private List content; G}tq'#]E{z
2S1wL<qP
/** 2
AZ[gr@c
* The default constructor ~67L
*/ nD\X3g`V
public Result(){ S-8O9
super(); [`^x;*C
} iaR^] |7_
4ifWNL^)
/** 7CGKm8T
* The constructor using fields LDL#*g
* Kl[WscR
* @param page XV2f|8d>
* @param content IkSzjXE{
*/ t/,k{5lX
public Result(Page page, List content){ Cm;WQuv@
this.page = page; ?Rl?Pp=>
this.content = content; %aX<p{EY
} BPnZ"w_
,=tVa])
/** uBk$zs
* @return Returns the content. jZ <*XX
*/ ;APpgt4
publicList getContent(){ 46'EZ@#s
return content; Ed|7E_v
} 'M\ou}P
xA nAW
/** Llf>C,)
* @return Returns the page. g eaeOERc
*/ snTj!rV/_
public Page getPage(){ x3L3K/qMg
return page; $-VW)~Sl
} SvH=P!`+
E'LkoyI
/** l}X3uyS
* @param content t-SGG{
* The content to set. voaRh@DZ%/
*/ F!VC19<1O8
public void setContent(List content){ 17G7r\iNYq
this.content = content; $Q|66/S^
} Nuk\8C
FuaGr0]
/** EOV<|WF>
* @param page 0[0</"K%1m
* The page to set. ^HKxaW9W
*/ `3r *Ae
publicvoid setPage(Page page){ p&bQ_ XOH
this.page = page; 4qjY,QJ
} G%anot
} 9VIsLk54^
;W#G<M&n'
x>5#@SX
J
Hux#v>e
8T
6jM+ h
2. 编写业务逻辑接口,并实现它(UserManager, 3}$L4U
#hzs,tvvD
UserManagerImpl) XH)MBr@Fz
java代码: iD@2_m)
SsafRK$
<acAc2
/*Created on 2005-7-15*/ Vm&fw".J
package com.adt.service; @ky5XV
}mz4 3Sq<
import net.sf.hibernate.HibernateException; xYRL4
LL-MZ~ZB
import org.flyware.util.page.Page; \J0gzi.
a +*|P
import com.adt.bo.Result;
4MRHz{`wa
CN:
36
/** <s-_ieW'
* @author Joa ?
Z8_(e0U
*/ av
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publicinterface UserManager { 1kl4X3q6
g9I2SdaJ
public Result listUser(Page page)throws vK#xA+W
fCZbIt)Eh
HibernateException; ~&k1P:#R
1h]Dc(Oc#=
} "xS",6Sy
wamqeb{u
" I`<s <
`-Gs*#(/
Tb}`]Y`X
java代码: /5suyM=U
*BBP"_$
6}Y^X
/*Created on 2005-7-15*/ @<},- u
package com.adt.service.impl; X"8Jk4y
tTF/$`Q#*
import java.util.List; )1J&tV*U
_V6;`{$WK
import net.sf.hibernate.HibernateException; F:IG3 @
HnioB=fc
import org.flyware.util.page.Page; v"_hWJ)
import org.flyware.util.page.PageUtil; &hd+x5
z7{b>oub('
import com.adt.bo.Result; r6 ,5&`&
import com.adt.dao.UserDAO; 8Z/P<u
import com.adt.exception.ObjectNotFoundException; 4<Bj;1*4
import com.adt.service.UserManager; kHX- AsRc
5@Ot@o
/** !K(0)~u
* @author Joa 8*4X%a=Of
*/ vYmRW-1Zxq
publicclass UserManagerImpl implements UserManager { FL0(q>$*8
$+S'Boo
private UserDAO userDAO; uGc}^a2
04:^<n+{
/** K!HSQ,AC
* @param userDAO The userDAO to set. E n{vCN
*/ eNu`\
publicvoid setUserDAO(UserDAO userDAO){ N}VKH5U|
this.userDAO = userDAO; 3HFsR)
} RH6qi{)i!
98Pt&C? -B
/* (non-Javadoc) |53Zg"!
* @see com.adt.service.UserManager#listUser TS$ 2K
Q>JJI:uC4
(org.flyware.util.page.Page) cl1h;w9s
*/ M*8Ef^-U`t
public Result listUser(Page page)throws /S\P=lcb
5cgDHs
HibernateException, ObjectNotFoundException { %{&yXi:mS
int totalRecords = userDAO.getUserCount(); Po(9BRd7
if(totalRecords == 0) gAgzM?A1(
throw new ObjectNotFoundException rMfp%DMA
Mh[;E'C6
("userNotExist"); LJfd{R1y+
page = PageUtil.createPage(page, totalRecords); !4]wb!F
List users = userDAO.getUserByPage(page); ui YZk3
returnnew Result(page, users); q*?LXKi
} /u*((AJ?Qv
ggJn oL
} ^0ipM/Lg
~F+{P4%`<
vUvIZa
aJOhji<b#L
MY4cMMjp~
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 zg0)9br
=d.Z:L9d
询,接下来编写UserDAO的代码: { >bw:^F
3. UserDAO 和 UserDAOImpl: FJp~8
x=
java代码: d*3k]Ie%5f
(Pbdwzao
\;.\g6zX
/*Created on 2005-7-15*/ +P6q
wh\v
package com.adt.dao; yWsNG;>
@iS(P u
import java.util.List; ~*- eL.
E
Rqr0>x
import org.flyware.util.page.Page; |.)oV;9
k)1K6ug
import net.sf.hibernate.HibernateException; j0Kj>
nRPy)L{
/** f,k'gM{K
* @author Joa &LwR9\sh
*/ pI,QkDJ0
publicinterface UserDAO extends BaseDAO { TmoODG>@
,L6d~>=41
publicList getUserByName(String name)throws l~!\<, !
liA)|.H
HibernateException; SQ1.jcWW[
k/u6Cw0/
publicint getUserCount()throws HibernateException; o;D87E6Z
zVd2kuI&?
publicList getUserByPage(Page page)throws U_wn/wcLS
S}cpYjnH8
HibernateException; C~yfuPr\B
1*Yf[;L
} V&eti2&zO
UMma|9l(i
0 j:8Ve
R/Mwq#xUb
nws '%MK)
java代码: e>#*$4tg
mawomna
2+s_*zM-
/*Created on 2005-7-15*/ )~rfx
package com.adt.dao.impl; |ITp$_S
sbjAZzrX2i
import java.util.List; (/a2#iW
<IC=x(T
import org.flyware.util.page.Page; S1E=E5
ug.mY= n'
import net.sf.hibernate.HibernateException; 1y2D]h /'
import net.sf.hibernate.Query; J{
P<^<m_
\3-XXq
import com.adt.dao.UserDAO; !\'7j-6
+?w 7Nm`
/** GLp2
?fon
* @author Joa #5wOgOv
*/ hq6B
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public class UserDAOImpl extends BaseDAOHibernateImpl &na#ES$X,
=;W"Pi;*
implements UserDAO { .0:BgM
3{LXx
/* (non-Javadoc) O#7ONQfBO
* @see com.adt.dao.UserDAO#getUserByName Hzcy'
:2pd2 S
(java.lang.String) XI}
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*/ GbFLu`I u
publicList getUserByName(String name)throws : ^F+mQN
5x(`z
HibernateException { 5|my}.TR
String querySentence = "FROM user in class J;W(}"cFq
?l!L
)!2
com.adt.po.User WHERE user.name=:name"; ig4wwd@|
Query query = getSession().createQuery %0fF_OU
r Lg(J|^
(querySentence); vIF=kKl9,
query.setParameter("name", name); Sf);j0G,D
return query.list(); )@09Y_9r
} X^r5su?
\V
/s
/* (non-Javadoc) SpPG
* @see com.adt.dao.UserDAO#getUserCount() EgOAEv
*/ Jkzt=6WZ0
publicint getUserCount()throws HibernateException { X6kB
R
int count = 0; rbiNp6AdL
String querySentence = "SELECT count(*) FROM bY|%ois4
#+N\u*-S
user in class com.adt.po.User"; bE#=\kf|
Query query = getSession().createQuery 1t_$pDF}
hb9e6Cc
(querySentence); guz{DBlK
count = ((Integer)query.iterate().next KE1S5Mck>
PVP,2Yq!
()).intValue(); Fq!12/Nn
return count; F1JSf&8
} %Koc^
pb)
4:q<<vCJv
/* (non-Javadoc) %_0,z`f
* @see com.adt.dao.UserDAO#getUserByPage k_/hgO
IT!
a)d
(org.flyware.util.page.Page) &I
Iw>,,
*/ 1 mhX3
publicList getUserByPage(Page page)throws (Z"QHfO'
A%>Ir`I
HibernateException { e4p:Zb:
String querySentence = "FROM user in class h#'(i<5v
L+LxS|S+M
com.adt.po.User"; Vc.A<(
Query query = getSession().createQuery Sj]k5(&
pJrc\`D
(querySentence); z~Ph=1O>p
query.setFirstResult(page.getBeginIndex()) X0O0Y>"
.setMaxResults(page.getEveryPage()); X|K"p(N
return query.list(); !8yw!hA
} ML'4 2z
Y
jIv%?8+%
} *Dtwr
nr*~R-,\
DeE-M"
!4GGq
Pk9s~}X
至此,一个完整的分页程序完成。前台的只需要调用 }hrLM[
s\i=-`
userManager.listUser(page)即可得到一个Page对象和结果集对象 G;_QE<V~_
iwWy]V m7
的综合体,而传入的参数page对象则可以由前台传入,如果用 AVVL]9b_2
A"x1MjuqLM
webwork,甚至可以直接在配置文件中指定。 4o8uWS{`
vZj^&/F$=g
下面给出一个webwork调用示例: mA}-hR%
java代码: Q}FDu,
J\<7M8
0* <gGC
/*Created on 2005-6-17*/ L@2%a'
package com.adt.action.user; #c@Dn.W
\?c0XD
import java.util.List; ^8$CpAK]M
]y3V^W#
import org.apache.commons.logging.Log; RmxgCe(2a
import org.apache.commons.logging.LogFactory; 2ME"=!&5
import org.flyware.util.page.Page; z"*X/T
UZ0fw@R M
import com.adt.bo.Result; IG0$OtG
import com.adt.service.UserService; :VP4|H#SP
import com.opensymphony.xwork.Action; })!d4EcZf
-NtT@ +AE
/** *T"JO|
* @author Joa c|3%0=,`
*/ Mnyg:y*=
publicclass ListUser implementsAction{ T0s7aw[zm
%^[45e
privatestaticfinal Log logger = LogFactory.getLog S>OfUrt
Kdh(vNB>
(ListUser.class); TJ[C,ic=D
Y,RED5]t
private UserService userService; v39`ct= e
*#1&IJPI
private Page page; >Z?fX
q4{Pm $OW
privateList users; 9;2PoW8
vl*CU"4
/*
RR!(,j^M
* (non-Javadoc) '$pT:4EuGq
* `}.K@17
* @see com.opensymphony.xwork.Action#execute() h=SQ]nV{
*/ }[}u5T`w>
publicString execute()throwsException{ m6^Ua
Result result = userService.listUser(page); @*q WV*$h
page = result.getPage(); v'Ce|.;
users = result.getContent(); *F* c
return SUCCESS; Dww]D|M
} EW*!_|
H=])o21
/** !R;P"%PHV
* @return Returns the page. v ~.X
*/ <h|XB}s+
public Page getPage(){ VTk6.5!8
return page; <J-bDcp
} Mf7Q+_!
_F>1b16:/P
/** y[[f?rxz>
* @return Returns the users. 'EU{%\qM
*/ Z
l.}=
publicList getUsers(){ DLcfOOn1I
return users; JPfNf3<@My
} %<$CH],%
+Q_(wR"FS
/** =Xze ).g
* @param page # m?GBr%k
* The page to set. "6_#APoP
*/ fgg^B[(Y
publicvoid setPage(Page page){ `M/=_O3
this.page = page; E9pKR+P
} O$u;]cg
4r#O._Z
/** jb1OcI%
* @param users \DBoe:0~
* The users to set. '`?\CXX
*/ /tRzb8`
publicvoid setUsers(List users){ n4\6\0jq6
this.users = users; !Sr^4R +Z
} "
]
0ER
l=D E|:
/** xal,j*
* @param userService ov: h4
* The userService to set. b\NWDH7}
*/ xb\(>7M6Y
publicvoid setUserService(UserService userService){ =o;QvOS;
this.userService = userService; ^-{ 1]G:
} hPr*<2mp
} Sxf|gDC
!e@G[%k
RrKAgw
a
OR}
~J?O ~p`&
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, uA=6 HpDB
oc'#sE
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 HRIf)n&~f
*V#v6r7<Y/
么只需要: zMs]9o
java代码: g`)3m,\
84L!r
r5Ej
<?xml version="1.0"?> zk5sAHQ
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork +*,rOK`C
zf$&+E-
1.0//EN" "http://www.opensymphony.com/xwork/xwork- Hb'fEo r
9(lIz{
1.0.dtd"> lz\{ X
*cCr0\Z`
<xwork> pC(AM=RY!
}<7Dyn,
<package name="user" extends="webwork- ,e+.Q#r*Y
'KpCPOhfR
interceptors"> D *W+0
dvxD{UH
<!-- The default interceptor stack name Q_QmyD~m
Y<3s_
--> ]*j>yj.Y'~
<default-interceptor-ref ,'5P[-
?15k~1nA
name="myDefaultWebStack"/> /b6Y~YbgU
TFbCJ@X
<action name="listUser" bL_s[-7
Uy^Hh4|
class="com.adt.action.user.ListUser"> d|TRP,y
<param seY0"ym&e
2g-'.w
name="page.everyPage">10</param> Y?%MPaN:
<result RBr
@dX0gHU[c
name="success">/user/user_list.jsp</result> U#G
uB&V
</action> S1uW`zQ!+_
CvmZW$5Yo
</package> D}"\nCz}y&
j)Kk:BFFY
</xwork> a1ZGMQq!
p`gg
OH5
kT$
j^KM
As@~%0 S
J x-^WB
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 @A!Ef=R
q9pBS1Ej
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。 #[sC H
%_M B-
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 ~U*2h =]
^*C6]*C}te
SZg+5MD;X
"V~U{(Z
(~-q}_G;Q
我写的一个用于分页的类,用了泛型了,hoho hw_7N)}
./kmI#gaV
java代码: >IfJ.g"
t(lTXG
YV-2es+Bd
package com.intokr.util; W#e:r z8=
r&}fn"H!
import java.util.List; l*_b)&CH
IaE};8a8
/** <y*#[:i
* 用于分页的类<br> 6BW-AZc
* 可以用于传递查询的结果也可以用于传送查询的参数<br> W~W^$A
* 5gF}7D@
* @version 0.01 JC{}iG6r+
* @author cheng kSU*d/}*u
*/ <S
$Z
public class Paginator<E> {
)%;#~\A
privateint count = 0; // 总记录数 `]5XY8^kI
privateint p = 1; // 页编号 {eIE|
privateint num = 20; // 每页的记录数 tRbZ^5x\@
privateList<E> results = null; // 结果 #Vul#JHW
#.9Xkn9S
/** BxZ}YS:
* 结果总数 >~BU<#
*/ (n"M)
publicint getCount(){ ,~K_rNNZ
return count; ?jw)%{iKYV
} Z>QSZ48=
A40 -])'!
publicvoid setCount(int count){ PG<N\
this.count = count; rorzxp{
} z &<Rx[
P_-zkw
/** NXeo&+F
* 本结果所在的页码,从1开始 TM!R[-\
* Vz 5:73
* @return Returns the pageNo. 1b6gTfU
*/ xO1d^{~^^
publicint getP(){ 6J%SkuxR
return p; XF^c(*5
} ys+?+dY2
#l;Ekjfz
/** I_pA)P*Q(6
* if(p<=0) p=1 0)ST_2Ci
* +Ya-h~7;g#
* @param p
C&e
*/ %Pa-fee
publicvoid setP(int p){ `9K'I-hv<8
if(p <= 0) 9%zR?u
p = 1; DVTzN(gO*~
this.p = p; 4i~;Ql
} qh.c#t
J\;~(:
~
/** M?nnpO
* 每页记录数量 .)cOu>
*/ &`>*3m(
publicint getNum(){ l*X5<b9
return num; ~PlwPvWo
} 5I&^n0h|&
[&{"1Z
/** DN^ln%#
* if(num<1) num=1 5V?1/
*/ /%xK-z,V
publicvoid setNum(int num){ U#F(#3/
if(num < 1) *D<sk7
num = 1; ,{oP`4\Lm
this.num = num; W_sDF; JP
} "X]ufZ7
//LXbP3/
/** ;V@}
oD+
* 获得总页数 `gss(o1}
*/ { @-Q1
publicint getPageNum(){ ?: meix
return(count - 1) / num + 1; (4g;-*N
} `Z@wWs
,E>VYkoA
/** |(P>'fat-p
* 获得本页的开始编号,为 (p-1)*num+1 e#zGLxa
*/ S0yPg9v
publicint getStart(){ erqm=)
return(p - 1) * num + 1; P$pl
} P?0b-Qr$a
)bK<t
/** _K;rM7
* @return Returns the results. O-y"]Wrv
*/ ?QuFRl,ZJ
publicList<E> getResults(){ xxV{1, H2
return results; +=}%
7o
} T|{BT!
W1E
|f>y"T+1
public void setResults(List<E> results){ 9*2hBNp+
this.results = results; !Uj !Oy
} +Nza@B d
cnIy*!cJs
public String toString(){ [9LYR3 p
StringBuilder buff = new StringBuilder vuAAaKz
g|+G(~=e|
(); P&F)E#Sa
buff.append("{"); N%?o-IY
buff.append("count:").append(count); '[juPI(!
buff.append(",p:").append(p); eq@ v2o7
buff.append(",nump:").append(num); a"EQldm|d
buff.append(",results:").append "QlCcH`g
u!@P,,NY
(results); K^w9@&