Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 $|8!BOx8t
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 =>-Rnc@
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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 I_]^ .o1q
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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 {.XEL
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分页支持类: q.;u?,|E/
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java代码:
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package com.javaeye.common.util; *WuID2cOI
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import java.util.List; 7<*yS310
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publicclass PaginationSupport { m^zUmrj[
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publicfinalstaticint PAGESIZE = 30; yU*8|FQbP
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privateint pageSize = PAGESIZE; $&n=$C&x
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privateList items; aht[4(XH5
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privateint totalCount; {N+$Q'
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privateint[] indexes = newint[0]; ;>Ib^ov
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privateint startIndex = 0; ) AvN\sC
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public PaginationSupport(List items, int {ttysQ-
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totalCount){ >G25m'&,7
setPageSize(PAGESIZE); |IzPgC
setTotalCount(totalCount); RMdk:YvBg
setItems(items); ZbdZrE$
setStartIndex(0); W:pIPDx1=!
} ;~m8;8)
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public PaginationSupport(List items, int vg32y /l]S
3[Qxd{8r
totalCount, int startIndex){ r7%I n^k
setPageSize(PAGESIZE); V Y7[)
setTotalCount(totalCount); AP 2_MV4W
setItems(items); *XIF)Q=<>
setStartIndex(startIndex); inMA:x}cF1
} *RJG!t*t
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public PaginationSupport(List items, int rlOAo`hd
D2Kp|F;
totalCount, int pageSize, int startIndex){ 286jI7 T
setPageSize(pageSize); 52Z2]T
c,
setTotalCount(totalCount); 4V)kx[j
setItems(items); mn"G_I
setStartIndex(startIndex); 8V`WO6*
} &5B'nk"
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publicList getItems(){ KQ% GIz x
return items; 7x|9n
} $r@zs'N
wd8l$*F*
publicvoid setItems(List items){ <lPm1/8
this.items = items; SJn;{X>)q
} 0d)M\lG
61C7.EZZ;
publicint getPageSize(){ \/r}]Vz
return pageSize; 3Ei#q+7
} gwuI-d^
]8_NZHld
publicvoid setPageSize(int pageSize){ Qb-M6ihcc
this.pageSize = pageSize; -P$PAg5"2
} $]/{[@5
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publicint getTotalCount(){ dVtG/0
return totalCount; 99e.n0
} P9^Xm6QO
u5`u>.!
publicvoid setTotalCount(int totalCount){ XPXIg
if(totalCount > 0){ _$E6P^AQ
this.totalCount = totalCount; |.: q
int count = totalCount / )0]'QLH
r,73C/*&/
pageSize; 'x#~'v*
if(totalCount % pageSize > 0) @alK;\
count++; NZ:,ph
indexes = newint[count]; @1roe
G
for(int i = 0; i < count; i++){ 3wF;GG
indexes = pageSize * t\dN DS
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i; < `=j^LU
} ;WQve_\
}else{ T4Uev*A
this.totalCount = 0; ZPLm]I\]
} N)X3XTY
} sUO`u qZV
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publicint[] getIndexes(){ Rsm^Z!sn
return indexes; i>`%TW:g
} B6DYZ+7A
>y7?-*0
publicvoid setIndexes(int[] indexes){ Ty?cC**
this.indexes = indexes; *~e?TfG
} L,/%f<wd
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publicint getStartIndex(){ 'o2Fa_|<#
return startIndex; %YscBG
} H/
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publicvoid setStartIndex(int startIndex){ ""G'rN_=Bi
if(totalCount <= 0) K($Npuu]
this.startIndex = 0; N:/D+L
elseif(startIndex >= totalCount) 1.GQau~
this.startIndex = indexes sY&IquK^
z>Y-fN`,
[indexes.length - 1]; *i%.;Z"
elseif(startIndex < 0) zwjgE6
this.startIndex = 0; A?P_DA
else{ AQvudx)@"
this.startIndex = indexes Bnxm HGP#&
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[startIndex / pageSize]; wlqksG[B
} Ow,w$0(D
} "<1{9
yR{3!{r3(
publicint getNextIndex(){ ;N0XFjdR
int nextIndex = getStartIndex() + '-~~-}= sJ
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pageSize; q>+k@>bk@
if(nextIndex >= totalCount) VY4yS*y
return getStartIndex(); ?N9uu4
else +=</&Tm
return nextIndex; bWU'cw
} d\8l`Krs[_
htF] W|z
publicint getPreviousIndex(){ +ye3HGD
int previousIndex = getStartIndex() - 0aB;p7~&
E ~<JC"]
pageSize; 9rf)gU3{+L
if(previousIndex < 0) `d}2O%P
return0; jQB9j
else BRiE&GzrF
return previousIndex; lt8|9"9<
} *z8\Lnv~k
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} eeB{c.#
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抽象业务类 ~Mxvq9vaD
java代码: MQ8J<A Pf-
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/** C~/a-
* Created on 2005-7-12 k{-Cwo
*/ P&LsVR{#
package com.javaeye.common.business; ]c'A%:f<
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import java.io.Serializable; ep{FpB
import java.util.List; S)@j6(HC4
ujpJ@OWj
import org.hibernate.Criteria; sfl<qD+?
import org.hibernate.HibernateException; F:S}w
import org.hibernate.Session; UkFC~17P
import org.hibernate.criterion.DetachedCriteria; A.w.rVDD
import org.hibernate.criterion.Projections; }O
p;
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import 4j^
@wV'
vnuN6M{
org.springframework.orm.hibernate3.HibernateCallback; & 1f+,
import N"ST@/j.A
c7H^$_^ =
org.springframework.orm.hibernate3.support.HibernateDaoS ZbKg~jdF
'LDQgC*%
upport; 7b+6%fV
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import com.javaeye.common.util.PaginationSupport; =Dj#gV
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public abstract class AbstractManager extends 4^<?Wq~
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HibernateDaoSupport { o)/ 0a
@2i9n
privateboolean cacheQueries = false; #KvlYZ+1
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privateString queryCacheRegion; RxQ *
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publicvoid setCacheQueries(boolean r9XZ(0/p
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cacheQueries){ eyxW 0}[
this.cacheQueries = cacheQueries; |w3M7;~eF
} `WS&rmq&'
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publicvoid setQueryCacheRegion(String &7s.`
dc'Y`e
queryCacheRegion){ cWm$;`Q#\
this.queryCacheRegion = mR)wX 6
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queryCacheRegion; G#$-1"!`
} 0"SU_jQzv
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publicvoid save(finalObject entity){ q,%st~
getHibernateTemplate().save(entity); y1#1Ne_
} cz$2R
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publicvoid persist(finalObject entity){ B-mowmJ3dg
getHibernateTemplate().save(entity); xyxy`qR A
} qg$ <oL@~~
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publicvoid update(finalObject entity){ 2KZneS`
getHibernateTemplate().update(entity); W%Fv p;\`
} H,NF;QPPC
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publicvoid delete(finalObject entity){ A=>u
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getHibernateTemplate().delete(entity); "Y.y:Vv;
} )M^
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publicObject load(finalClass entity, #LNED)Vg
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finalSerializable id){ o !7va"
return getHibernateTemplate().load t`QENXA}
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(entity, id); @%SQFu@FJ
} K>
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publicObject get(finalClass entity, Ir]\|t
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finalSerializable id){ 'B}qZCy W
return getHibernateTemplate().get ,z?':TZ
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(entity, id); yDS4h(^
} wA.\i
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publicList findAll(finalClass entity){ i mM_H;-X
return getHibernateTemplate().find("from ']oQ]Yx0
-$@h1Y
" + entity.getName()); QS j]ZA
} <-0]i_4sK
}1xo-mUg,
publicList findByNamedQuery(finalString ?%kV?eu'
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namedQuery){ "w_aM7x_
return getHibernateTemplate 9>$p
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().findByNamedQuery(namedQuery); 4.(4x&
} hzC>~Ub5
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publicList findByNamedQuery(finalString query, SY8C4vb'h
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finalObject parameter){ "h ^Z
return getHibernateTemplate ze;KhUPRm
@lt#Nz
().findByNamedQuery(query, parameter); LIdF 0
} 59-c<I/}f
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publicList findByNamedQuery(finalString query, )_NO4`ejs/
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finalObject[] parameters){ $7uA%|\
return getHibernateTemplate {_dvx*M
0?M:6zf_iv
().findByNamedQuery(query, parameters); 39jG8zr=Z[
} .[ mRM
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publicList find(finalString query){ =rK+eG#,
return getHibernateTemplate().find uwBiW
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(query); Q3SS/eNP
} fxIf|9Qi`
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publicList find(finalString query, finalObject YAmb`CP
<^uBoKB/f
parameter){ _-F s#f8
return getHibernateTemplate().find CWS4lx
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(query, parameter); V470C@
} I`p;F!s
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public PaginationSupport findPageByCriteria :a)u&g@G
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(final DetachedCriteria detachedCriteria){ 2 Vrw
return findPageByCriteria b%5f&N
= 9]~yt
(detachedCriteria, PaginationSupport.PAGESIZE, 0); {.\TtE
} v}Fr@0%
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public PaginationSupport findPageByCriteria IN G@B#Cl
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(final DetachedCriteria detachedCriteria, finalint ;d9QAN&0}
8ITdSg
startIndex){ $p?aVO
return findPageByCriteria *`RkTcG
aAA U{EWW
(detachedCriteria, PaginationSupport.PAGESIZE, 8pgEix/M5o
bbyg8;/
startIndex); 5o8EC"
0
} {jX2}
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public PaginationSupport findPageByCriteria FG*r'tC~r
/RC7"QzL
(final DetachedCriteria detachedCriteria, finalint ^M>P:~
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pageSize, Tyf`j,=
finalint startIndex){ W1=H8O
return(PaginationSupport) =>af@C.2
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getHibernateTemplate().execute(new HibernateCallback(){ s+?zL~t
publicObject doInHibernate 7{I0s;R
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(Session session)throws HibernateException { m-"w0Rl1T
Criteria criteria = vTzlwK\#1
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detachedCriteria.getExecutableCriteria(session); r
# cGop]
int totalCount = Y#P%6Fy
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((Integer) criteria.setProjection(Projections.rowCount <;Zmjeb+#
I75DUJqy]
()).uniqueResult()).intValue(); EGF '"L
criteria.setProjection l3I:Q^x@
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(null); |Uh
List items = 'Xq|Kf (
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criteria.setFirstResult(startIndex).setMaxResults 9H`XeQ.
54R#W:t
(pageSize).list(); iN8zo:&Z
PaginationSupport ps = Doyx[zZ
LR.<&m%~.
new PaginationSupport(items, totalCount, pageSize, fN^8{w/O
]{mPh\
startIndex); ~^fZx5
return ps; dufu|BL|}
} (b-MMr
}, true); EC!02S
} }" %?et(
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public List findAllByCriteria(final W^LY'ypT
DJ [#5h5
DetachedCriteria detachedCriteria){ 7XLtN "$$
return(List) getHibernateTemplate '3DXPR^B6
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().execute(new HibernateCallback(){ gS]@I0y8
.
publicObject doInHibernate 4`]^@"{
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(Session session)throws HibernateException { gANuBWh8T
Criteria criteria = {|_M
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detachedCriteria.getExecutableCriteria(session); j8{i#;s!"
return criteria.list(); a PfO$b:
} tla
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}, true); QIvVcfM^
} hl (hJfp
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public int getCountByCriteria(final L<-_1!wh
)E@.!Ut4o
DetachedCriteria detachedCriteria){ uHvp;]/0\
Integer count = (Integer) |[ k.ii6iO
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getHibernateTemplate().execute(new HibernateCallback(){ ex9g?*Q
publicObject doInHibernate =9["+;\e&
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(Session session)throws HibernateException { ag#S6E^%S
Criteria criteria =
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ith
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detachedCriteria.getExecutableCriteria(session); foF({4q7b^
return aa?b`[Xa
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criteria.setProjection(Projections.rowCount K>r,(zgVc
2"kLdD
()).uniqueResult(); 3kIN~/<R+7
} ZaDyg"Tw+
}, true); ^HThN
return count.intValue(); ~'iHo]9O
} qL&[K>2z
} fk[-mZ
$@Rxrx_@M
djQH1^(IU
'(VJ&UlS2
KRLQ #,9
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用户在web层构造查询条件detachedCriteria,和可选的 f/NH:1)y
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 "XKy#[d2
?m=N]!n
PaginationSupport的实例ps。 :O?MSS;~
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ps.getItems()得到已分页好的结果集 *_{j=sd
ps.getIndexes()得到分页索引的数组 MS>Ge0P("~
ps.getTotalCount()得到总结果数 )uIe&B
ps.getStartIndex()当前分页索引 6BHXp#
#z
ps.getNextIndex()下一页索引 wj<6kG
ps.getPreviousIndex()上一页索引 ooL!TSGD
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!/*\}\'4
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@= Uh',F
@* jz
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 qu6D 5t
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 (KD RkE|=
&yTqZ*Yuk
一下代码重构了。 <8i//HOE
,GIyq)
我把原本我的做法也提供出来供大家讨论吧: #7$
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B6As,)RjD:
首先,为了实现分页查询,我封装了一个Page类: k&q;JyUi
java代码: IH&|Tcf\
v0+BkfU+p
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/*Created on 2005-4-14*/ ,RI Gc US
package org.flyware.util.page; [{,T.;'<j
GPv1fearl
/** |A9F\A->4
* @author Joa vHc%z$-d
* =sU<S,a*
*/ G1tY) _-8[
publicclass Page { t?&|8SId
6f>{"'
/** imply if the page has previous page */ 8.=BaNU
privateboolean hasPrePage; 2'\H\|
M,,bf[p$
/** imply if the page has next page */ Xp% v.M
privateboolean hasNextPage; P [ck84F/
hJ? O],4J
/** the number of every page */ glxsa8
privateint everyPage; "ycJ:Xv49
A#<? 4&
/** the total page number */ |O+H[;TB6
privateint totalPage; rJTa
`r':by0M
/** the number of current page */ /NFj(+&g+
privateint currentPage; k FD;i
n\'4
/** the begin index of the records by the current 9YyLf ;
(OL4Ex' ]
query */ Bahm]2
privateint beginIndex; Y('#jU
KC6.Fr{
#x60xz
/** The default constructor */ MrFQ5:=
public Page(){ ,PW'#U:
7U"g3a)=
} Pn1^NUMZJ
KYI/
/** construct the page by everyPage Eyqa?$R
* @param everyPage q~o<*W
* */ p)-^;=<B3
public Page(int everyPage){ #q$HQ&k
this.everyPage = everyPage; rJ4S%6w
} + GN(Ug'R
8/cX]J
/** The whole constructor */ #p&qUw
public Page(boolean hasPrePage, boolean hasNextPage, |aS.a&vwR
lb3bm)@:
t%)7t9j
int everyPage, int totalPage, -d/
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int currentPage, int beginIndex){ J!(<y(l
this.hasPrePage = hasPrePage; 9Q.Yl&A
this.hasNextPage = hasNextPage; my1@41
H
this.everyPage = everyPage; 3;9^
this.totalPage = totalPage; pah'>dAL
this.currentPage = currentPage; R) h#Vc(
this.beginIndex = beginIndex; %aCqi(.7
} [|$h*YK
LonxT&"!D
/** Nh|uO?&C6
* @return t{9GVLZ
* Returns the beginIndex. K5h
*/ vA{-{Q
publicint getBeginIndex(){ >]TWXmx/w
return beginIndex; 5C]x!>kX
} M|h3Wt~7
`U_)98
/**
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* @param beginIndex "(O>=F&
* The beginIndex to set. h[Y1?ln&h
*/ bAqA1y3=
publicvoid setBeginIndex(int beginIndex){ j,eo2HaL
this.beginIndex = beginIndex; wwZ ,;\
} \M^bD4';>
~36!?&eA8
/** TD0
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* @return 8GUX{K
* Returns the currentPage. #;yZ
*/ kTgEd]^&D
publicint getCurrentPage(){ H1./x6Hr
return currentPage; -Q*gW2KmV
} oMa6(3T?E
?6U0PChy
/** kl:Bfs)b
* @param currentPage f]CXu3w(J
* The currentPage to set. y<Ot)fa$
*/ Dp9+HA9t
publicvoid setCurrentPage(int currentPage){ {P_.~0pc*
this.currentPage = currentPage; 26h21Z16q
} |CyE5i0
G"t5nHY\.
/** b>ySv
* @return =Xr.'(U
* Returns the everyPage. JWxwJex
*/ #ABZ&Z
publicint getEveryPage(){ \9T7A&
return everyPage; <e6#lFQqK
} cvL;3jRo
;2QP7PrSY
/** &};zvo~P.
* @param everyPage <a3WKw
* The everyPage to set. ?:0Jav
*/ 8quaXVj^a
publicvoid setEveryPage(int everyPage){ CrTw@AW9)
this.everyPage = everyPage; pQB."[n
} 5b7RYV
Q3?F(ER@
/**
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* @return (TM,V!G+U~
* Returns the hasNextPage. F#E3q|Q"BS
*/ !&E-}}<
publicboolean getHasNextPage(){ f|gg
return hasNextPage; E]r?{t`]
} $*m-R*kt
lyhiFkO
iH
/** Tlr v={
* @param hasNextPage f|(M.U-
* The hasNextPage to set. (/]
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*/ u ^RxD^=L
publicvoid setHasNextPage(boolean hasNextPage){ A3*!"3nU
this.hasNextPage = hasNextPage; F:DrX_O%
} _@/8gPT*i
a8Wwq?@
/** \'j|BJ~L f
* @return Dvln/SBk
* Returns the hasPrePage. <OPArht
*/ `M6)f?|$.
publicboolean getHasPrePage(){ #`s"WnP9'!
return hasPrePage; vZ Lf
} 9N3eN
|ENh)M8}r
/** Oow2>F%_#
* @param hasPrePage R G`1en
* The hasPrePage to set. P0b7S'a4!
*/ #.[k=dj
publicvoid setHasPrePage(boolean hasPrePage){ U/BR*Zn]*
this.hasPrePage = hasPrePage; teVM*-
} ml$o5&sN
ehY5!D1Q
/** L/^I*p,
* @return Returns the totalPage. <54
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* A5w6]: f2
*/ 40
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publicint getTotalPage(){ /u+e0BHo
return totalPage; DlNX 3
} CJI~_3+K
WjqO@]P6
/** RpYERAgT
* @param totalPage wlmRe`R
* The totalPage to set. ^Zp>G{QL{
*/ VLN_w$iEq
publicvoid setTotalPage(int totalPage){ #R
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this.totalPage = totalPage; 7t_^8I%[
} ~F7gP{r
;jTN| i'
} 8-6L|#J#
kO-(~];
RCLeA=/N@0
SK.: Q5:
5NLDYi@3
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 A.w:h;7
1@=po)Hnp
个PageUtil,负责对Page对象进行构造: *_g$MI
java代码: 2VCI 1E
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k.15CA`
/*Created on 2005-4-14*/ f'3$9x
package org.flyware.util.page; 5 + MS^H
e64 ^ChCoV
import org.apache.commons.logging.Log; Q.c\/&
import org.apache.commons.logging.LogFactory; Y:)e(c"A
7 x?<*T
/** $]2vvr
* @author Joa W'u>#
* K,:N
*/ -+-_I*(
publicclass PageUtil { S?BG_J6A7
c-FcEW
privatestaticfinal Log logger = LogFactory.getLog %C_HXr@
eO[b1]WLP
(PageUtil.class); j^2j&Ta
KdbHyg<4
/** }?v )N).kW
* Use the origin page to create a new page K@w{"7}
* @param page c_!cv":s
* @param totalRecords >t_6B~x9
* @return ,UdVNA
*/ ayF\nk4b
publicstatic Page createPage(Page page, int h;NYdX5
SGlNKA},A
totalRecords){ Q#[9|A9
return createPage(page.getEveryPage(), >Wg hn:^
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page.getCurrentPage(), totalRecords); FH+s s!
} HT1!5
C8i^P}y
/** TBU&6M>{3
* the basic page utils not including exception "OnGE$
qPfQy
handler a-L;*
* @param everyPage _b;{_g
* @param currentPage 0}quG^%_
* @param totalRecords !f&g-V
* @return page O/(xj2~$J
*/ ]f9Cx\d:k
publicstatic Page createPage(int everyPage, int j]/RC(;?
"o}+Ciul
currentPage, int totalRecords){ P1' al
everyPage = getEveryPage(everyPage); i5,kd~%O
currentPage = getCurrentPage(currentPage); :${HQd+
int beginIndex = getBeginIndex(everyPage, (n9gkO&8"
M{hg0/}sUW
currentPage); /{--+
C
int totalPage = getTotalPage(everyPage, =^ 50FI|
>>fH{/l
totalRecords); .gOL1`b*
boolean hasNextPage = hasNextPage(currentPage, Y#$%iF
B%+T2=&$7
totalPage); IG9VdDj
boolean hasPrePage = hasPrePage(currentPage); ~|xA4u5LG
yhA6i
returnnew Page(hasPrePage, hasNextPage, u.Tcg^ v
everyPage, totalPage, v^iL5y!
currentPage, yFlm[K5YD
9.B
KI/
beginIndex);
oc0G|
} "y/?WQ>,3
7CTFOAx#
privatestaticint getEveryPage(int everyPage){ |3yL&"
return everyPage == 0 ? 10 : everyPage; JQHvz9Yg
} tc{sB\&-
!6Mo]xh
privatestaticint getCurrentPage(int currentPage){ O2dW6bt
return currentPage == 0 ? 1 : currentPage; V~;1IQd{
} ve2u=eQ1
@xYlS5{
privatestaticint getBeginIndex(int everyPage, int k4y'b
dP]\Jo=Yh
currentPage){ `W/>XZl+t
return(currentPage - 1) * everyPage; CDR@
`1-
} h/hmlnOQl
[>5-$Y OT
privatestaticint getTotalPage(int everyPage, int RxWVe-Dg
2/=l|!JKLz
totalRecords){ @>>~CZ`l
int totalPage = 0; bsA-2*Q+
3/W'V,5G6
if(totalRecords % everyPage == 0) /F'sb[
totalPage = totalRecords / everyPage; 4s{~r
else (uZ&V7l
totalPage = totalRecords / everyPage + 1 ; wLJ:\_Jaf
g0Gf6o>2
return totalPage; YRN06*hS
} v+#}rUTF
7f!YoW;1
privatestaticboolean hasPrePage(int currentPage){ $jqq
`n_
return currentPage == 1 ? false : true; UH-*(MfB
} rb+j*5Es
]B3=lc"
privatestaticboolean hasNextPage(int currentPage, Vi]W |bP
T@&K-UQ
int totalPage){ Rww{:R
return currentPage == totalPage || totalPage == w\i\Wp,FP
(w/T-*
0 ? false : true; Xe:jAkDp
} 8sTp`}54J
9V@V6TvW>&
G5aieD.#
} Ne{?:h.!
'2nhv,|.U
PV\+P6aIb
^^as'Dk
}Nm#q@o$P
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。 jiS_G%G
Q1
$^v0-)
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 {NFr]LGOp
@l jA
做法如下: N&g3t%F
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 b
Y\K
4;]hK!AXS
的信息,和一个结果集List: mA+&Io
java代码: L`p4->C9A
D rHVG
*%fi/bimG
/*Created on 2005-6-13*/ v>Yb/{A
package com.adt.bo; <[\`qX
kJzoFFWo$
import java.util.List; [] `&vWZ
=JbRu|/
import org.flyware.util.page.Page; %GA"GYL9'
evAMJ=
/** -Rd/Gx
* @author Joa QWSTR\!
*/ .C(eh
publicclass Result { >qjq=Ege
rrqR}}l
private Page page; 4Thn])%I
Ix!Iw[CNd
private List content; L>W'LNXCv
q6SXWT'Sa
/** MVTMwwO \[
* The default constructor w?wG(+X7
*/ vss(twg
public Result(){ : $Y9jR
super(); 3z)Kz*xr
} UA8GL D9
3U.88{y
/** &U
raUl
* The constructor using fields MgOR2,cR
* YY)s p%
* @param page S=<}:#;u0
* @param content A3no~)wZn
*/ l(u.I2^o
public Result(Page page, List content){ *`\Pr
this.page = page; Xti[[s J
this.content = content; O[s{ Gk'>
} s'a/j)^
Z
X(z;|l45
/** gp^5#
* @return Returns the content. d + / &?3
*/ %?uc><&?e
publicList getContent(){ ;WM"cJo9
return content; $Ifmc`r1
} X4AyX.p
ZP*q4:
/** sCi s4gX.]
* @return Returns the page. +!z{5:
*/ RIXMJ7e7
public Page getPage(){ RHq/JD-
return page; Z!@~>i
} *-q"3D`
/<}m? k\
/** >.'*)@vQi
* @param content Nz+949X
* The content to set. %Nhx;{
*/ ,TPISs
public void setContent(List content){ g[Ib,la_a
this.content = content; ##;Er47@^
} 65p?Igb
#H{<gjs]
/** C>$E%=h+_
* @param page 2H6,'JK@F
* The page to set. j =WST
*/ jbu8~\"
publicvoid setPage(Page page){ 8p9bCE>\
this.page = page; 9C[ywp
} SWQ5fcPu
} tqeZ#w7
kc @[9eV
zG9Y!SY\-
!n$tr
AvSM^
2. 编写业务逻辑接口,并实现它(UserManager, .J.-Mm`.
jhu&&==\f
UserManagerImpl) CkD#/
java代码: ;SaX;!`39+
Y&_&s7z
NqEA4C
/*Created on 2005-7-15*/ dBe`p5Z
package com.adt.service; oiyzHx
.I'o
import net.sf.hibernate.HibernateException; c`WHNky%j
R~jHr
)0.#
import org.flyware.util.page.Page; IS[thbzkZ
'+vA\(K
import com.adt.bo.Result; w@c87;c
|-
rI@2`
/** ,^ WJm?R
* @author Joa >O?U=OeD
*/ <Ib[82PU
publicinterface UserManager { :.d:9Z|_
!]fQ+ *X0g
public Result listUser(Page page)throws d&u]WVU
*gF<m9&
HibernateException; d/|D<Sb[s
:ORR_f`>
} }kK[S|XVO
=;|QZ"%E
FwY&/\J7V
f<*Js)k
MR,R}B$
java代码: I,VH=Yn5,
^Q ps>A(
nF4a-H&Fo
/*Created on 2005-7-15*/ .OqSch|
package com.adt.service.impl; !!V#v9{
e9Pk"HHl
import java.util.List; ~-t>z
b}wC|\s
import net.sf.hibernate.HibernateException; k({\/t3i
c.f"Gv
import org.flyware.util.page.Page; {
"xln/
import org.flyware.util.page.PageUtil; :nS;W
G,<T/f
.{$
import com.adt.bo.Result; RQB]/D\BO
import com.adt.dao.UserDAO; Gqcz<=/
import com.adt.exception.ObjectNotFoundException; L9ap(
import com.adt.service.UserManager; zT|)uP*
X _G| hx
/** j:&4-K};Z`
* @author Joa 'K*AV7>E
*/ OxtOd\0$
publicclass UserManagerImpl implements UserManager { l|+BC
?D)<,
private UserDAO userDAO; Xy5s^82?
#:|+XLL
/** 9F-
)r'
* @param userDAO The userDAO to set. 'snn~{hG
*/ 5,;`$'?a%
publicvoid setUserDAO(UserDAO userDAO){ G"59cv8z4R
this.userDAO = userDAO; -MugnB6
} u=NSsTP&
j9U%7u]-k
/* (non-Javadoc) qXW})(
* @see com.adt.service.UserManager#listUser J.+BD\pa
8; R|
(org.flyware.util.page.Page) V~yAE@9
*/ %tt%`0
public Result listUser(Page page)throws J3b4cxm
.E~(h*NW
HibernateException, ObjectNotFoundException { d~_`M0+
int totalRecords = userDAO.getUserCount(); YyJPHw)Z
if(totalRecords == 0) SL&hJs4c'
throw new ObjectNotFoundException H{c?lT
dj&}Gedy
("userNotExist"); ZC4*{
page = PageUtil.createPage(page, totalRecords); iH2n.M
"
List users = userDAO.getUserByPage(page); m&0"<V!H/B
returnnew Result(page, users); "SoHt]%#
} 5ZPzPUa8~
Q2%QLM:.,
} O:/yAc`
0l#)fJo
cj|*_}
u%d K ig
$7Mtt.d6
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 >71&]/Rv
&&<9p;E
询,接下来编写UserDAO的代码: O^I[
(8Y8
3. UserDAO 和 UserDAOImpl: }2r+%V&4
java代码:
5q<zN
+1Ph<zq"
Lx U={Y0
/*Created on 2005-7-15*/ 5[9bWB{
package com.adt.dao; X#UMIlU
wj|x:YZ*
import java.util.List; >7U>Yh
j#6|V]l
import org.flyware.util.page.Page; iG,t_??
LDy<k=;o
import net.sf.hibernate.HibernateException; Zx?b<"k
6ZqgY1
/**
0gF!!m
* @author Joa cM &'[CI
*/ HT_TP q
publicinterface UserDAO extends BaseDAO { Y/8K;U|
[$(R#tZ+
publicList getUserByName(String name)throws cQZ652F9
$\Tkhq<
HibernateException; @gBE{)Fj
q1hMmMi
publicint getUserCount()throws HibernateException; Q7o5R{.oJ
N 6O8Wn
publicList getUserByPage(Page page)throws dd7 =)XT+
2#/p|$;Ec'
HibernateException; 2$zU&p7sV
Q\J,}1<`6
} QI!i
#S+Z$DQD
7yiJ1K<bIt
-#A:`/22
c;I, O
java代码: +MO E
M\+* P,i
8xI`jE"1
/*Created on 2005-7-15*/ W)SjQp6
package com.adt.dao.impl; mf|pNiQ,
-05U%l1e
import java.util.List; TL)O-
gS"Q=ZK"
import org.flyware.util.page.Page; r7!J&8;{K
YirC*
import net.sf.hibernate.HibernateException; eE/%6g
import net.sf.hibernate.Query; {rkn q_;0
8R69q:
import com.adt.dao.UserDAO; af+}S9To
8h?X!2Nq
/** 26:evid
* @author Joa 5>ST"l_ca
*/ O'}llo
public class UserDAOImpl extends BaseDAOHibernateImpl ?9u4a_x
{%']w
implements UserDAO { d\XRUO[
i&@,5/'-_O
/* (non-Javadoc) ^ZQCIS-R
* @see com.adt.dao.UserDAO#getUserByName LEc8NQs
DQ=N1pft2v
(java.lang.String) j[S`^2
*/ iTNqWU-o
publicList getUserByName(String name)throws ?:|YGLaB
U?U(;nSR\A
HibernateException { j/<??v4F4
String querySentence = "FROM user in class uJ'9R`E ]1
A1,4kqmE
com.adt.po.User WHERE user.name=:name"; B$`lYDqaG
Query query = getSession().createQuery gf$HuCh|
-%uy63LbHF
(querySentence); 5&4F,v[zp
query.setParameter("name", name); yCM{M
return query.list(); $M]%vG
} A"/aGCG0z
>7>7/7=O
/* (non-Javadoc) %9c|%#3
* @see com.adt.dao.UserDAO#getUserCount() }?O[N}>,m
*/ Yn[x #DS
publicint getUserCount()throws HibernateException { `5"/dC
int count = 0; CT5Y/E?}
String querySentence = "SELECT count(*) FROM ehc<|O9tY
@&/\r
7
'
user in class com.adt.po.User"; ?2~U2Ir]:
Query query = getSession().createQuery 8SD}nFQ
=O^7TrM
(querySentence); R/N<0!HZ
count = ((Integer)query.iterate().next l:tpL(%
ofEqvoi@
()).intValue(); {qAu/ixp
return count; tvWH04T
} KHJ=$5r)
mW$ot.I
/* (non-Javadoc) -iQsi4
* @see com.adt.dao.UserDAO#getUserByPage "<dN9l>
ur xqek
(org.flyware.util.page.Page) !yCl(XT
*/ Q}uG/HI
publicList getUserByPage(Page page)throws ;2W2MZ!TF
RUrymkHFB
HibernateException { $u,GVq~
String querySentence = "FROM user in class [oHOHp/V
w:tGPort
com.adt.po.User"; DM/hcY$MW
Query query = getSession().createQuery Y<ElJ>A2I
$PfV<Yj'B
(querySentence); >DmRP7v
query.setFirstResult(page.getBeginIndex()) chwh0J;
.setMaxResults(page.getEveryPage()); cJq<9(
return query.list(); |\p5mh
} anitqy#E
xXa#J)'
} #HcI4j:s!
qi[(*bFK7
'Fzuc^G(d
5k`e^ARf
s#Q_Gu
至此,一个完整的分页程序完成。前台的只需要调用 LsotgQ8
>\-3P$
userManager.listUser(page)即可得到一个Page对象和结果集对象 Hrv),Ce
wL|7mMM,
的综合体,而传入的参数page对象则可以由前台传入,如果用 hd=j56P5P
= P8~n2V
webwork,甚至可以直接在配置文件中指定。 IgiqFV{
w\v&3T
下面给出一个webwork调用示例: I_L;T
java代码: 'qlxAYw<f
j)<[j&OWw
Gm*Uv6?H?
/*Created on 2005-6-17*/ ht$ WF
package com.adt.action.user; D1~^\)*
3 \9][S-B
import java.util.List; 0kz7 >v
f8F1~q
import org.apache.commons.logging.Log; "x.88,T6
import org.apache.commons.logging.LogFactory; ?ZM^%]/+
import org.flyware.util.page.Page; k%a?SU<f
x_pMG!2
import com.adt.bo.Result; ;op'V6iG
import com.adt.service.UserService; _PdAN= C3
import com.opensymphony.xwork.Action; 1uj05aZh}
c; d"XiA
/** $u-lo|
* @author Joa 1o)=GV1
*/ )muv;Rf`e5
publicclass ListUser implementsAction{ ees^O{ 8
nvwDx*[qN
privatestaticfinal Log logger = LogFactory.getLog J4&XPr9
8Y]}Gb!
(ListUser.class); BfEx'C
k4*! Q_A
private UserService userService; v,@E}F~-f1
zh
hGqz[K
private Page page; j?d!}v
c8!j6\dC*
privateList users; )m> 6hk
Wpa$B
)xg
/* EsNk<Ra
* (non-Javadoc) PH{c,
* 4jPwL|#
* @see com.opensymphony.xwork.Action#execute() {K6Kx36
*/ z4nou>
publicString execute()throwsException{ >cSi/a,L
Result result = userService.listUser(page); $R3.yX=[\
page = result.getPage(); T=Ol`?5
users = result.getContent(); 2@OBeR
return SUCCESS; `,Q <YT ~
} U
&f#V=Rg
CJtr0M<U+
/** \_)02ZT:
* @return Returns the page. ]r]+yM|
*/ -y9Pn>~V
public Page getPage(){ Ed8U;U b
return page; fa/P%9db
} C!oksI
Rb yF#[}
/** =k_XKxd
* @return Returns the users. 23,%=U
*/ 1@s^$fvW
publicList getUsers(){ y`T--v3mI
return users; Y|Nfwqz
} a'o}u,e5
,OFq'}q
/** w@4t$bd7
* @param page oT$(<$&<
* The page to set. +YkmLD
*/ v_[)FN"]Y.
publicvoid setPage(Page page){ F?!};~$=Z
this.page = page; fB@K'JQG
} -(|7`U
Qj{$dqmDN
/** `mh-pBVD1
* @param users Q;d+]xj
* The users to set. B=r]_&u-u
*/ dY4 8S{
publicvoid setUsers(List users){ oR!n bm
this.users = users; &! 5CwEIF
} ?nj"Ptzs
+6i7,U
/** MLEIx()
* @param userService JuKk"tr~RB
* The userService to set. #3AYz82w
*/ 9
kTD}" %2
publicvoid setUserService(UserService userService){ QfKR
pnj(o
this.userService = userService; "Yc^Nc
} L5i#Kh_
} !-
Cs?
g!~-^_F
5&GQ=m
p3>Q<
mdmZ1:PBM
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, 'Y~8_+J?
JMl, N
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 %5( EkP
.Bm ^3A
么只需要: #VP-T; Ahe
java代码: v ^ FV
t
^!-E`<jW8
7TMDZ*
<?xml version="1.0"?> {+9^PC_hm;
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork }R?v"6aBS
lN*1zM<6;
1.0//EN" "http://www.opensymphony.com/xwork/xwork- \(3Qqbw
P22y5z~
1.0.dtd"> Wme1Uid
*_<SWTE
<xwork> TV$\v@\ =
}+QhW]nO{F
<package name="user" extends="webwork- 6_ 33*/>=c
BIHHRCe:@n
interceptors"> \]~kyy
ePPp)=
<!-- The default interceptor stack name f<$K.i
LRqw\fKk[
--> -=v/p*v0o
<default-interceptor-ref g9grfN
"'&>g4F`o
name="myDefaultWebStack"/> d=c1WK
*cI6&;y
<action name="listUser" !z"a_
m;$F@JJ
class="com.adt.action.user.ListUser">
k=d%.kg
<param 6@ (k8<3
nEZ-h7lzl(
name="page.everyPage">10</param> {YxSH%
<result Rd@n?qB
)U/@J+{{
name="success">/user/user_list.jsp</result> fjz2m
</action> m`1}O"<&i
~8n~4
</package> eaZ)1od
]
_]6&PZXk
</xwork> -h^} jP8
=4w^)'/
S9F]!m^i
)ZuQ;p
#4|i@0n}D
$.x?in|_
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 PL$(/Z
!m/Dd0
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。 v2W"+QS}u
Ej{eq^n
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 4.Jaw+
ngH~4HyT
c?3F9w#
ck4T#g;=
9DP75 ti
我写的一个用于分页的类,用了泛型了,hoho 1rvf\ [
\Im\*A
java代码: "8j;k5<
k0Vo
LBiv]3
package com.intokr.util; zLIa! -C
MWd_6XM
import java.util.List; TckR_0LNV
LF3GVu,
/** >TJKH^7n
* 用于分页的类<br> ^VLUZ
* 可以用于传递查询的结果也可以用于传送查询的参数<br> |Bf:pG!
* Q1>Op$>h
* @version 0.01 ] l qFht
* @author cheng VlQwVe
*/ M0" g/W
public class Paginator<E> { tV}ajs
privateint count = 0; // 总记录数 (HX [bG`
privateint p = 1; // 页编号 q.hc%s2?
privateint num = 20; // 每页的记录数 _-yF9g"I
privateList<E> results = null; // 结果 "'p+qbT8
}s)&/~6
/** =~2 Uv>YG
* 结果总数 j/` qd(=B
*/ Lq8Z!AIw>
publicint getCount(){ /IQ-|Qkg
return count; `b'|FKc]
} F~0%j}ve
N~K)0RETn
publicvoid setCount(int count){ YC,.Y{oY{
this.count = count; 3S2p:\]
} VA&OI;=ri
fylA0{
/** c%,6L <[
* 本结果所在的页码,从1开始 3x;y}:wQa
* C9;X6
* @return Returns the pageNo. $\J9F=<a
*/ {p_vR/yN
publicint getP(){ #o |&MV_j
return p; r1H['{$
} CR8r|+(8
\oZUG
/** <cS7L0h
* if(p<=0) p=1 o B}G^t
* @ke})0`5
* @param p ^1&
LHrT
*/ "jN-Yd,z
publicvoid setP(int p){ `/j|Rb|eow
if(p <= 0) `0WA!(W
p = 1; u:u 7|\q
this.p = p; GbrPtu2{@V
} ~9'4w-Sy
{{)[Ap)
/**
*/dsMa
* 每页记录数量 `]I5WTt*X
*/ 3usA
publicint getNum(){ z&J ow/
return num; 1^"aR#
} C-b% PgA
$j2)_(<A%Q
/** +mW$D@Pf
* if(num<1) num=1 tJF~Xv2L!
*/ GBOmVQ $Hb
publicvoid setNum(int num){
G?1V~6
if(num < 1) ``)1`wx$
num = 1; yt#;3
this.num = num; +jZg%$Q!#
} N#!1@!2BN
9^*YYK}%
/** ='||BxB
* 获得总页数 A VG`r2T
*/ NX #d}M^V
publicint getPageNum(){ 8!`.%)- 4
return(count - 1) / num + 1; adPU)k_j:
} Lj* =*V
!!X9mI|2|
/** 6f9<&dCK
* 获得本页的开始编号,为 (p-1)*num+1 K[yJu 4
*/ _eeX]xSSl
publicint getStart(){ v2=!*
return(p - 1) * num + 1; [?6D1b[
} yzzre>F
6uE1&-:L
/** ;Sl0kSu
* @return Returns the results. Gqb-3ngH
*/ q@Yt`$VTN
publicList<E> getResults(){ tZ24}~da
return results; JkDZl?x5
} 'Mhdw}
={vtfgxl
public void setResults(List<E> results){ U$J_:~
this.results = results; { RX|
} jY6=+9Jz5
rd~W.b_b
public String toString(){ dnc!=Z89
StringBuilder buff = new StringBuilder
]p.f*]
NGZ>:
(); "/h"Xg>q
buff.append("{"); L"<Eov6
buff.append("count:").append(count); A;HKR4p;8
buff.append(",p:").append(p); h#;K9#x6
buff.append(",nump:").append(num); i4Cb&h^
buff.append(",results:").append QjbPBk Q
vX24W*7
(results); 84\o7@$#
buff.append("}"); `mTxtuid{
return buff.toString(); ^G<M+RF2J
} !0+Ex
F
,/U9v~
} ri V/wN9C
{!bJ.O
l
t[ocp;Q