Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 H<gC{:S
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 )Ha`>
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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 Q Pel n)
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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 7Nw}
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分页支持类: L<GF1I)
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java代码: 9:JFG{M
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package com.javaeye.common.util; V>8)1)dF
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import java.util.List; fV 6$YCf
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publicclass PaginationSupport { aJQx"6c?
p "J^
publicfinalstaticint PAGESIZE = 30; \R m2c8Z2
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privateint pageSize = PAGESIZE; 7wO0d/l_
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privateList items; mKsTA;
72YL
privateint totalCount; <c,/+
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privateint[] indexes = newint[0]; AU3Ou5
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privateint startIndex = 0; \Mi] !b|8
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public PaginationSupport(List items, int u-31$z<<5}
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totalCount){ lbRm(W(
setPageSize(PAGESIZE); h1y6`m9
setTotalCount(totalCount); $. ;j4%%
setItems(items); [RZ}9`V
setStartIndex(0); ~miRnW*x
} 0+i\j`O&
T:/68b*H\:
public PaginationSupport(List items, int Up(Jw-.
FMuakCic5
totalCount, int startIndex){ g^CAT1}
setPageSize(PAGESIZE); !<ae~#]3P
setTotalCount(totalCount); (>E}{{>2r
setItems(items); &oA p[]
setStartIndex(startIndex); EB/.M+~a
} ;AFF7N>&
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public PaginationSupport(List items, int FUq>+U!Qu
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totalCount, int pageSize, int startIndex){ c]pO'6]
setPageSize(pageSize); dHcGe{T^(
setTotalCount(totalCount); +
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setItems(items); Kn#3^>D
setStartIndex(startIndex); p6VHa$[
} 4z~%gt74O]
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publicList getItems(){ D92#&,KD
return items; 7_AR()CM
} @Ju!|G9z/p
v7"Hvp3w
publicvoid setItems(List items){ X(b"b:j'
this.items = items; ~)RKpRga\p
} 2n9E:tc
)u. ut8![T
publicint getPageSize(){ UE3#(:xA
return pageSize; JG2)-x;9
} b&Dc DX
O_PKS$sz{
publicvoid setPageSize(int pageSize){ 8a\
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this.pageSize = pageSize; 9$9Pv%F:j
} ;'\{T#5)
%H-(-v^T*
publicint getTotalCount(){ QU&b5!;&
return totalCount; ++s=$D
} IZ2c<B5&
Q~5!c#r
publicvoid setTotalCount(int totalCount){ uW.)(l
if(totalCount > 0){ zUw9
this.totalCount = totalCount; y.zS?vv2g
int count = totalCount / $X.X_
}y-b<J?H
pageSize; ]LvpYRU$P
if(totalCount % pageSize > 0) Ha~g8R&
count++; 29+p|n
indexes = newint[count]; VfJbexYT
for(int i = 0; i < count; i++){ H8>u:
indexes = pageSize * u&iMY3=
1 :xN )M,s
i; sA3=x7j%c
} |eEcEu?/b
}else{ {r9fKA
this.totalCount = 0; Y.O/~ af
} YN\!I
} \O"EK~x}/
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publicint[] getIndexes(){ p,y(Fc~]g'
return indexes; J?ljqA}i
} ub|tX 'o
Ok-*xd
publicvoid setIndexes(int[] indexes){ !6t
()]
this.indexes = indexes; >Q0HqOq
} J%?'Q{
V 0<>Xo%
publicint getStartIndex(){ t^h{D
return startIndex; OUY65K
} O
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Qrt[MJ+#
publicvoid setStartIndex(int startIndex){ SwESDo)
if(totalCount <= 0) zOR
this.startIndex = 0; `(|jm$Q
elseif(startIndex >= totalCount) ;cBFft}D
this.startIndex = indexes ]M|Iy~
X
MB,;HeP!
[indexes.length - 1]; N?d4Pu1m
elseif(startIndex < 0) ;c5Q"
this.startIndex = 0; LT sG
else{ +tz^ &(
this.startIndex = indexes V$Y5EX
1mw<$'pm0
[startIndex / pageSize]; j HT2|VGb*
} $7{V+>
} /cBQE=]6
s)q;{wz
publicint getNextIndex(){ gB!K{ Io'
int nextIndex = getStartIndex() + ~
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pageSize; m/"\+Hv
if(nextIndex >= totalCount) 7Zl-|
return getStartIndex(); djVE x}
else i[b?W$]7
return nextIndex; w,
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} CB5 ~!nKv&
T,h,)|:I^
publicint getPreviousIndex(){ c43"o
int previousIndex = getStartIndex() - J7R+|GTcx
DCfV
pageSize; `;L0ax
if(previousIndex < 0) "M*Pt
return0; C'ZF#Z
else `F:PWG`
return previousIndex; p1 tfN$-
} /#?lG`'1
rIz"_r
} ruM16*S{=
1!. CfQi
t@-:e^ v
U$KdY _Z97
抽象业务类 vVF#]t b|
java代码: 2RDos#
K#g)t/SZ
h3.wR]ut
/** {9KG06%+
* Created on 2005-7-12 F"9f6<ge
*/ {\G4YQ
package com.javaeye.common.business; zO`54^
Fl GKy9k
import java.io.Serializable; UO}Kk*
import java.util.List; 7>EjP&l
e!}R1
import org.hibernate.Criteria; (
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import org.hibernate.HibernateException;
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import org.hibernate.Session; !8]W"@qb
import org.hibernate.criterion.DetachedCriteria; k3se<NL[
import org.hibernate.criterion.Projections; D,+I)-k<
import Q nikgV
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org.springframework.orm.hibernate3.HibernateCallback; v"Bv\5f,Ys
import ZWW:-3
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org.springframework.orm.hibernate3.support.HibernateDaoS NL))!Pi
li\hH d5
upport; bh:;ovH
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import com.javaeye.common.util.PaginationSupport; SE{$a3`UzP
d;\x 'h2
public abstract class AbstractManager extends 0Ph,E
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HibernateDaoSupport { *nD yB.(
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privateboolean cacheQueries = false; [Fe`}F}Co8
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privateString queryCacheRegion; ;ej;<7+
ptGM'
publicvoid setCacheQueries(boolean J\XYUs
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cacheQueries){ yef@V2Z+
this.cacheQueries = cacheQueries; 0*W=u-|s6
} ~h?zK1
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publicvoid setQueryCacheRegion(String u!mUUFl
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queryCacheRegion){ MsCY5g
this.queryCacheRegion = @rkNx@[~
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queryCacheRegion; V3K
} om$)8'A,l
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publicvoid save(finalObject entity){ FVsVY1
getHibernateTemplate().save(entity); z+&mMP`-
} ~oz8B^7i;
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publicvoid persist(finalObject entity){ 8.Wf^j$+{
getHibernateTemplate().save(entity); W"YFx*W
} CHv~H.kh'
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publicvoid update(finalObject entity){ "n:z("Q*
getHibernateTemplate().update(entity); >}GtmnF
} vL{sk|2&
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publicvoid delete(finalObject entity){ QM`A74j0]\
getHibernateTemplate().delete(entity); Ki{&,:@
} "zL<:TQ"
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publicObject load(finalClass entity, i[H`u,%+(
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finalSerializable id){ 0sto9n3
return getHibernateTemplate().load G+[hE|L~y
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(entity, id); 3i=+ [
} nJY#d;
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publicObject get(finalClass entity, Zm!T4pL
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finalSerializable id){ {<o_6 z`$
return getHibernateTemplate().get 2G<\Wz
nAG2!2_8
(entity, id); ?<bByxa
} h7f&7v
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publicList findAll(finalClass entity){ f1y3l1/
return getHibernateTemplate().find("from yt}Ve6 m
x
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" + entity.getName()); I9rWut@+
} 1[OCoj o<
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publicList findByNamedQuery(finalString Y^Y|\0
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namedQuery){ ~CCRs7V/L
return getHibernateTemplate /J )MW{;O
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().findByNamedQuery(namedQuery); CtJ*:wF
} YAQ]2<H
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publicList findByNamedQuery(finalString query, @?lmho?
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finalObject parameter){ uP2e/a
return getHibernateTemplate T'B4 3Q
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().findByNamedQuery(query, parameter); $_ IvzbOh
} Ndq/n21j
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publicList findByNamedQuery(finalString query, k=!lPIx
A?V}$PTlx
finalObject[] parameters){ 1=:=zyEEo
return getHibernateTemplate >>/|Q:
4Bg"b/kF
().findByNamedQuery(query, parameters); qM78s>\-h
} |`vwykhezO
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publicList find(finalString query){ 3kfrOf.4h
return getHibernateTemplate().find HR'sMu3
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(query); GPV=(}z
} OBY^J1St
j"=F\S&!
publicList find(finalString query, finalObject hK^(Y
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parameter){ fk%W07x!
return getHibernateTemplate().find =D-u".{
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(query, parameter); A1>fNilC9
} rSu+zS7`X
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public PaginationSupport findPageByCriteria {BV0Y.O
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(final DetachedCriteria detachedCriteria){ RZMR2fP%
return findPageByCriteria vq?Le j
g{ ()
(detachedCriteria, PaginationSupport.PAGESIZE, 0); suOWmqLs
} ,X`w/ 2O
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public PaginationSupport findPageByCriteria 'Fq+\J#%
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(final DetachedCriteria detachedCriteria, finalint 6LRvl6ik
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startIndex){ 8MQb5( !
return findPageByCriteria ~fnu;'fN
(>.lkR
(detachedCriteria, PaginationSupport.PAGESIZE, `;j@v8n$*
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startIndex); j+"w2
} 52,[dP,g
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public PaginationSupport findPageByCriteria 8sus$:Ry
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(final DetachedCriteria detachedCriteria, finalint { )g
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pageSize, n }kn|To~
finalint startIndex){ {gz-w|7
return(PaginationSupport) LvqWA}
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getHibernateTemplate().execute(new HibernateCallback(){ Gf=3h4
publicObject doInHibernate (S~kNbIa
4`e[gvh
(Session session)throws HibernateException { jd`h)4
Criteria criteria = vnN0o5
k{F]^VXQ
detachedCriteria.getExecutableCriteria(session); 9-+N;g!q
int totalCount = 5pT8 }?7
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((Integer) criteria.setProjection(Projections.rowCount lqTc6@:D
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()).uniqueResult()).intValue(); 2@N9Zk{{J
criteria.setProjection iE?yvtr8
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(null); c)3.AgT
List items = M5a&eO
u69UUkG
criteria.setFirstResult(startIndex).setMaxResults U8.V Rn
!bCSt?}@u
(pageSize).list(); ;}Ei #T,D
PaginationSupport ps = PN3 Qxi4F
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new PaginationSupport(items, totalCount, pageSize, uPq@6,+
'&+]85_&$
startIndex); jddhX]>I
return ps; fK6[ p&
} f^-ot@w
}, true);
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} 2!6E~<~HC
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public List findAllByCriteria(final $ q*a}d[Q
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DetachedCriteria detachedCriteria){ P!"{-m'
return(List) getHibernateTemplate &b`'RZe
I 12Zh7Cc:
().execute(new HibernateCallback(){ wH$qj'G4CN
publicObject doInHibernate twu,yC!
}hsNsQ
(Session session)throws HibernateException { eR,/}g\
Criteria criteria = soLW'8
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detachedCriteria.getExecutableCriteria(session); _9]vlxgtG(
return criteria.list(); -uxU[E
} H~TuQ
}, true); '}9 Nvr)+
} a{L&RRJ
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public int getCountByCriteria(final |gWA'O0S
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DetachedCriteria detachedCriteria){ HE35QH@/`
Integer count = (Integer) h
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getHibernateTemplate().execute(new HibernateCallback(){ z"T+J?V/
publicObject doInHibernate HAL\j5i
bf@g*~h@
(Session session)throws HibernateException { IIih9I`IR
Criteria criteria = ZG0^O"B0
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detachedCriteria.getExecutableCriteria(session); AmHj\NX$
return V'e%%&g~N
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criteria.setProjection(Projections.rowCount g<(!>:h
[.^ol6
()).uniqueResult(); f]#\&"
} .Sn{a}XP4
}, true); ?$K-f:?c
return count.intValue(); r-wCAk}m*?
} z]r'8Jc
} .SjJG67OyA
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用户在web层构造查询条件detachedCriteria,和可选的 bJetqF6n
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 6FNGyvBU
i_Hm?Bi!F
PaginationSupport的实例ps。 x;)I%c
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ps.getItems()得到已分页好的结果集 >({qgzV`
ps.getIndexes()得到分页索引的数组 ,\J 8(,%L
ps.getTotalCount()得到总结果数 2=- .@,6
ps.getStartIndex()当前分页索引 IK\~0L;ozE
ps.getNextIndex()下一页索引 h\UKm|BZ
ps.getPreviousIndex()上一页索引 x)*Lu">
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ?).;cG:<
M i& ;1!bg
,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 }lIc{R@H
##6\~!P
一下代码重构了。 {lWV H
p/-du^:2
我把原本我的做法也提供出来供大家讨论吧: #vBrRHuA#"
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首先,为了实现分页查询,我封装了一个Page类: It[51NMal
java代码: (p{%]M
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/*Created on 2005-4-14*/ Ob/)f)!!
package org.flyware.util.page; p[JIH~nb
4j=3'Z|
/** >8_y-74
* @author Joa QCW4gIp
* `f; w
*/ rNq*z,
publicclass Page { Cq!eAc
QT,T5Q%JP:
/** imply if the page has previous page */ gS~H1Ro
privateboolean hasPrePage; kM506U<g
#gQn3.PX+y
/** imply if the page has next page */ +r3)\L{U
privateboolean hasNextPage; Lto*L X
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M3Ve*
/** the number of every page */ P`lv_oV
privateint everyPage; <2U@O`
gC
JJd qdX;
/** the total page number */ pX_#Y)5
privateint totalPage; !G3AD3
PT2;%=f
/** the number of current page */ pJ]
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privateint currentPage; 9~Dg<wQ
!"F;wg$
/** the begin index of the records by the current /Sj~lHh
45c?0tj
query */ (zo7h
privateint beginIndex; |/gt;H~:
C#U(POA
Q~(Gll;
/** The default constructor */ M-^I! C
public Page(){ >R F|Q
{]Zan'{PCO
} 3s%?)z
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/** construct the page by everyPage jo:Z
* @param everyPage %4*c/ c6
* */ (A~7>\r +
public Page(int everyPage){ LlX)xJ
this.everyPage = everyPage; RM|J |R
} \(Sly&gL
LL( xi )
/** The whole constructor */ -%`~3*L
public Page(boolean hasPrePage, boolean hasNextPage, cdMSC7l!
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_@ao$)q{J
int everyPage, int totalPage, ;@ePu
int currentPage, int beginIndex){ K{ P-+(
this.hasPrePage = hasPrePage; fB$a)~
this.hasNextPage = hasNextPage; rwq
this.everyPage = everyPage; Z Ts*Y,
this.totalPage = totalPage; :TQp,CEa
this.currentPage = currentPage; T3{O+aRt
this.beginIndex = beginIndex; ?6:qAFw
} VExhN';
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/** z0}j7ns]
* @return 6 eSo.@*l
* Returns the beginIndex. k)b{UFRW
*/ b9j}QK
publicint getBeginIndex(){ =2p?_.|'
return beginIndex; d {!P
c<
} FSEf0@O:
w0BphK[
/** `yfZ{<
* @param beginIndex +VUkV-kP
* The beginIndex to set. eQ>Ur2H8n
*/ :=NXwY3~M
publicvoid setBeginIndex(int beginIndex){ [\ao#f0WR
this.beginIndex = beginIndex; doanTF4Da
} UdO8KD#r3
Ub3$ `
/** -N' (2'
* @return &hWELZe0vv
* Returns the currentPage. P'<i3#;7X
*/ %p}vX9U')
publicint getCurrentPage(){ [5P-K{Ko
return currentPage; x@
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} |ty&}'6C
(@^9oN~}
/** r8m}B#W7
* @param currentPage ;?Pz0,{h
* The currentPage to set. d'_q9uf'
*/ \lK?f] qJq
publicvoid setCurrentPage(int currentPage){ _`?0w#>0
this.currentPage = currentPage; \Tz|COG5h\
} 1GN^uia7
:BxO6@>Xc
/** 2U./
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* @return s\d3u`G
* Returns the everyPage. 1|sem(t
*/ ]xvA2!)Q
publicint getEveryPage(){ vsI;ooR>
return everyPage;
:a*>PMTn
} 6m&GN4Ca
u(Mbp$R'?
/** iF`_-t/k
* @param everyPage 5RLO}Vn]
* The everyPage to set. K\-N'M!Z
*/ 1sXCu|\q
publicvoid setEveryPage(int everyPage){ J^"_H:1[
this.everyPage = everyPage; VESvCei
} 9':Ipf&x
EeYL~ORdi
/** dg|+?M^9`
* @return X0j\nXk
* Returns the hasNextPage. T.#_v#oM
*/ >9w^C1"
publicboolean getHasNextPage(){ JlSqTfA
return hasNextPage; r8(oTx
} $@VJ@JAe
<);j5)/
/** `)O9
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* @param hasNextPage _L8&.=4]i
* The hasNextPage to set. %ZRv+}z
*/ Z&^vEQ
publicvoid setHasNextPage(boolean hasNextPage){ +/&rO,Ql
this.hasNextPage = hasNextPage; /,I?"&FWc
} W<<G
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/** 6ud?US(
* @return jpi,BVTI-X
* Returns the hasPrePage. rE*yT(:w
*/ 4"PA7
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publicboolean getHasPrePage(){ )-+tN>Bb
return hasPrePage; 86%k2~L
} >0kL9_9{
g,E)F90
/** e[k\VYj[
* @param hasPrePage CMC p7-v
* The hasPrePage to set. wPghgjF{
*/ uEPm[oyX
publicvoid setHasPrePage(boolean hasPrePage){ k&yBB%g
this.hasPrePage = hasPrePage; q|YnNk>1
} ft8
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/** '\H
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* @return Returns the totalPage. (QFZM"G
* G]l/L\{
*/ 34k(:]56|
publicint getTotalPage(){ <mLU-'c@
return totalPage; QdZHIgh`i
} /L,iF?7
d}E6d||A
/** ;d7Qw~v1s
* @param totalPage 7T X$
* The totalPage to set. Q-_;.xy#4
*/ a&)$s;
publicvoid setTotalPage(int totalPage){ !G;BYr>X
this.totalPage = totalPage; OG IN-
} 0Q%I[f8
eJOo~HIWQ
} ke*&*mx"L
ygm=q^bV]s
-}qay@cDt
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 5;{*mJ:F
Wi)N/^;n
个PageUtil,负责对Page对象进行构造: !H^R_GC
java代码: MMRO@MdfV
i+-Y"vRi
Gd&G*x
/*Created on 2005-4-14*/ 1g!%ej
jd
package org.flyware.util.page; GB>h8yXH
+],2smd@N
import org.apache.commons.logging.Log; ~}YgZ/U7T
import org.apache.commons.logging.LogFactory; "(F:'J} X
qB3&F pgW
/** ({rescQB
* @author Joa TAM`i3{ D
* r-BqIoVT
*/ [:Odb?+ `F
publicclass PageUtil { My9fbT
"^pF2JI
privatestaticfinal Log logger = LogFactory.getLog 5tbi};
A-hWg;
(PageUtil.class); mnMY)-6C
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/** >*w(YB]/$V
* Use the origin page to create a new page d cht8nX7~
* @param page 5PHAd4=bJ
* @param totalRecords Wm58[;%LTw
* @return 9hwn,=Vh)
*/ cRPy5['E
publicstatic Page createPage(Page page, int JENq?$S
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totalRecords){ n@e|PWu
return createPage(page.getEveryPage(), $/i;UUd
doe u`
page.getCurrentPage(), totalRecords); ( (mNB]sy
} ;#D:S6 L
%}~Ncn_r
/** 0Ioa;XgOn
* the basic page utils not including exception ]\R%@FCYc
[k
+fkr]
handler bDcWPwe
* @param everyPage bO{wQ1)Z_
* @param currentPage o@\q 6xl.
* @param totalRecords mK7egAo
* @return page i*vf(0G
*/ r#.\5aQt
publicstatic Page createPage(int everyPage, int my3W [3#
} SA/,4/9
currentPage, int totalRecords){ v?1xYG@1
everyPage = getEveryPage(everyPage); m>?{flO
currentPage = getCurrentPage(currentPage); V@>s]]HMq#
int beginIndex = getBeginIndex(everyPage, `Axn
ab5z&7Re6
currentPage); {wfe!f
int totalPage = getTotalPage(everyPage, [.iz<Yh
oxm3R8S
totalRecords); hz+x)M`Y
boolean hasNextPage = hasNextPage(currentPage,
OGO4~Up
$5l=&
totalPage); ?To r)>A'
boolean hasPrePage = hasPrePage(currentPage); ~4tu*\P
j.rJfbE|X
returnnew Page(hasPrePage, hasNextPage, #$>m`r
everyPage, totalPage, F0 FF:><
currentPage, a)8M'f_z
hbdM}"&]
beginIndex); 0~XZ
} SfwAMNCe
V5LzUg]
privatestaticint getEveryPage(int everyPage){ AA,n.;zy<
return everyPage == 0 ? 10 : everyPage; Q|o~\h<
} |q\:3R_0
VSt)~
privatestaticint getCurrentPage(int currentPage){ oW/ #/;|`
return currentPage == 0 ? 1 : currentPage; ) crhF9 !4
} F4Gv=q)Z
'`Z5.<n7p
privatestaticint getBeginIndex(int everyPage, int {o[*S%Z"
Dx27 s
currentPage){ f?A*g$v
return(currentPage - 1) * everyPage; i/UHDqZ
} i~6qOlLD-
oos7x6
privatestaticint getTotalPage(int everyPage, int DrB PC@^
VS \~t
totalRecords){ qMe$Qr8
int totalPage = 0; 9rmOf Jo:
It@.U|
if(totalRecords % everyPage == 0) M1T)e9k=x
totalPage = totalRecords / everyPage; 3 tp'}v
else T/&4lJ^2l^
totalPage = totalRecords / everyPage + 1 ; {aWTT&-N
q>*+.~
return totalPage; 8?O6IDeW
} 5}4r'P$m:
5l"v:Px
privatestaticboolean hasPrePage(int currentPage){ /u8m|S<
return currentPage == 1 ? false : true; 50.cMms
} y++[:M
auTApYS53
privatestaticboolean hasNextPage(int currentPage, =)3tVH&
3X&}{M:Qo
int totalPage){ Hb;#aXHSd
return currentPage == totalPage || totalPage == *.J)7~(P
#yk
m
0 ? false : true; ]QS?fs Z
} tQ:)j^\
Ln})\
UDK)
xCMcS~
3/
} @4D$Xl
S]3t{s#JW7
y#Ao6Od6
L= fz:H
4cni_m]
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。 8`*Wl;9u
)FkJ=P0
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 Og?]y ^y
/bj
D*rj
做法如下: K
-!YD}OF
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 XOzd{
S&% GB
的信息,和一个结果集List: %klC&
_g~_
java代码: mh"&KX86W
lmZSsx
Wej 8YF@
/*Created on 2005-6-13*/ T,,,+gPx
package com.adt.bo; gD0 FRKn
x-km)2x=W
import java.util.List; ;aip1Df
kckWBL
import org.flyware.util.page.Page; MkG3TODfHB
X9#;quco@
/** AAE8j.
* @author Joa Tt.wY=,K
*/ ?A/+DRQ(
publicclass Result { wG4=[d
QcGyuS.B
private Page page; 1;R1Fj&
V6Y:l9
private List content; |~Hlv^6H
w^?uBeqR
/** T<"Hh.h
* The default constructor R g7 O
*/ s('<ms
public Result(){ cWSiJr):r
super(); ]VY}VALZ
} : uglv6
Rdd[b?
/** y-gSal
* The constructor using fields :yo tpa
* V^WR(Q}
* @param page TpLlbsd
* @param content x8xSA*@k
*/ ML!Zm[I9
public Result(Page page, List content){ AXhV#nZt0
this.page = page; :4PK4D s7
this.content = content; <)L'h
} gN|[n.W4
A"8`5qa
/** o/bmS57
* @return Returns the content. Bkvh]k;F8
*/ &y/
publicList getContent(){ lV/-jkR
return content; GU\}}j]
} #y }{ 'rF?
P)Vm4u
1
/** |'xVU8
* @return Returns the page. gf()NfUvRH
*/ M/XxiF
public Page getPage(){ vkWh2z
return page; s)ymm7?
} 7{
zkqug
5_@ u Be~
/** sBGYgBu!a
* @param content Ly1V@
* The content to set. p.kJNPO\@
*/ #E%0 o
public void setContent(List content){ LwQq0<v
this.content = content; r]p
0O(
} (a0q*iC%
5T)qn`%
/** -z9-f\
* @param page 4hb<EH'_&
* The page to set. X(nbfh?n
*/ E Z95)pk
publicvoid setPage(Page page){ j_\nsM7
this.page = page; qi7(RL_N
} rnvKfTpZDU
} &L[7jA'[J
?YzOA${
og<mFbqkq7
C
7)w8y
X#KC<BXw,
2. 编写业务逻辑接口,并实现它(UserManager, 7/nnl0u8
dYdZt<6W<(
UserManagerImpl) &L[oQni];2
java代码: ],l
w
n4Od4&r
iq_y80g`8h
/*Created on 2005-7-15*/ EY=`/~|c
package com.adt.service; @giJ&3S,
.:?X<=!S&t
import net.sf.hibernate.HibernateException; B@Acm
z DDvXz
import org.flyware.util.page.Page; 42X N*br
;Z%PBMa
import com.adt.bo.Result; \~|+*^e)
7p'L(dq
/** bi`{ k\3A
* @author Joa |F_Z
*/ UX3
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publicinterface UserManager { {[~cQgCI
0F$;]zg
public Result listUser(Page page)throws dc[w`
"LyMw){
HibernateException; #-b0U[,.
g.![>?2$8
} <BoDLvW>
<T?H
H$es)
P%`|Tu!B
w E^6DNh
C{mL]ds<
java代码: Vsh7>|@
s ~'><ioh
H'N$Vv2q
/*Created on 2005-7-15*/ 6[g~p< 8n}
package com.adt.service.impl; XRi/O)98o
P70\ |M0~y
import java.util.List; DA'A-C2
\LX!n!@
import net.sf.hibernate.HibernateException; )c
vA}U.z
M{ #
import org.flyware.util.page.Page; LgN\%5f-
import org.flyware.util.page.PageUtil; !vNZ-}
L'XX++2
import com.adt.bo.Result; nO{@p_3mi
import com.adt.dao.UserDAO; Rv R,V
import com.adt.exception.ObjectNotFoundException; Sn 3@+9J
import com.adt.service.UserManager; x2gnB@t
,VK! 3$;|
/** @* a'B=7
* @author Joa e!cZW.B=`f
*/ 72oiO[>N'
publicclass UserManagerImpl implements UserManager { OnGtIY
Hd)z[6u8eT
private UserDAO userDAO; c5~d^
NPjh2 AJm
/** #$trC)? ~q
* @param userDAO The userDAO to set. o(iv=(o
*/ @.T
w*t
publicvoid setUserDAO(UserDAO userDAO){ M
XB
fX
this.userDAO = userDAO; @o&.]FZs
} Gt{'` P,&9
mIu-
/* (non-Javadoc) 9y/gWE
* @see com.adt.service.UserManager#listUser 1]eh0H
4h:R+o ^H^
(org.flyware.util.page.Page) e~7h8?\.q
*/ {)^P_zha[9
public Result listUser(Page page)throws -]=-IiC#
rN3i5.*/t
HibernateException, ObjectNotFoundException { sD V*k4
int totalRecords = userDAO.getUserCount(); utk'joo
if(totalRecords == 0) Vg1!
u+`<
throw new ObjectNotFoundException _ PC}`Y'&
=Rnx!E
("userNotExist"); Al?LO;$Pa?
page = PageUtil.createPage(page, totalRecords); s^nPSY!
List users = userDAO.getUserByPage(page); C:C9swik"5
returnnew Result(page, users); @)0-oa,u+
} q7id?F}3&
I{Pny/d`
} /rRQ*m_
b}P5*}$:9"
cp|&&q
![O@{/
IEb"tsel
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 K*&?+_v
:
F^iv1b
询,接下来编写UserDAO的代码: F_Q,j]0
3. UserDAO 和 UserDAOImpl: \L14rQ
t
java代码: H]:z:AAvX
Bsm>^zZ`YU
$)OUOv
/*Created on 2005-7-15*/ h'8w<n+%)
package com.adt.dao; 7Gb(&'n
s(yV E
import java.util.List; 5gpqN)|)[
/$OX'L&b
import org.flyware.util.page.Page; Kgi| 7w
p^_E7k<ag
import net.sf.hibernate.HibernateException; [oOA@
#A|~s;s>N
/** .hh2II
* @author Joa Up|\&2_
*/ ZB-+bY
publicinterface UserDAO extends BaseDAO { .F'fBT`$
(n{sp
publicList getUserByName(String name)throws +cAN4
x~."P*5
HibernateException; B7Um G)C
h-VpX6
publicint getUserCount()throws HibernateException; 51oZw%os=
Q
!5P
publicList getUserByPage(Page page)throws Ed/@&52z0
Gmcx#?|Tx
HibernateException; amI$0
&lYKi3}x
} Zp|LCE"
f[)_=T+
}vOUf#^k
_q([k_4h
cK.T=7T
java代码: md[FtcY\
CL(,Q8yG
EXz5Rue
LV
/*Created on 2005-7-15*/ I>b-w;cC
package com.adt.dao.impl; +NRn>1]
W%]sI n
import java.util.List; 6p/gvpZ
x{io*sY-
import org.flyware.util.page.Page; x>Ah4ad
\K 01F
import net.sf.hibernate.HibernateException; g
j`"|
import net.sf.hibernate.Query; n3{m
"h3
fM]McZ9)D
import com.adt.dao.UserDAO; ki6`d?
xh>/bU!>
/** H[ %Fo
* @author Joa .kM74X=S
*/ to Ei4u)m
public class UserDAOImpl extends BaseDAOHibernateImpl (^g?/i1@d
]?F05!$ *
implements UserDAO { 9E_C
u2B
3uwZ#
/* (non-Javadoc) r;w_B%9
* @see com.adt.dao.UserDAO#getUserByName V|NWJ7
`4s5yNUi=
(java.lang.String) x_Ki5~w5
*/ ?,r bD1
publicList getUserByName(String name)throws "fLGXbNQ
*qg9~/
HibernateException { /qF7^9LtaY
String querySentence = "FROM user in class O?@1</r^
=y7]9SOq
com.adt.po.User WHERE user.name=:name"; 3Z'{#<1>^;
Query query = getSession().createQuery G?QFF6)}!
jG{}b6
(querySentence); S>7Zq5*
query.setParameter("name", name); my")/e
return query.list(); uAyj##H
} Pi6C1uY6
sTqy-^e7
/* (non-Javadoc) ~nb%w?vv
* @see com.adt.dao.UserDAO#getUserCount() :EyH'v
*/ /#$bb4
publicint getUserCount()throws HibernateException { !mL,Ue3/
int count = 0; bi!4I<E>k
String querySentence = "SELECT count(*) FROM 14\%2nE
'2]u{rr~+
user in class com.adt.po.User"; i`r,B`V`08
Query query = getSession().createQuery f7X#cs)a
&tZ?%sr
(querySentence); UA,&0.7
count = ((Integer)query.iterate().next MCQ>BP
@Risabn
()).intValue(); ,@!8jar@w}
return count; xpyb&A
} *NV`6?o@6
K_`*ZV{r
/* (non-Javadoc) w;QDQ
fx0
* @see com.adt.dao.UserDAO#getUserByPage P0Na<)\'Y!
!N,Z3p>Q
(org.flyware.util.page.Page) 5 LX3.
*/ wRPBJ-C)
publicList getUserByPage(Page page)throws UF<|1;'
*ILS/`mdav
HibernateException { q30WUO;
String querySentence = "FROM user in class T-&CAD3 ,O
~N[hY1}X[
com.adt.po.User"; CpS'2@6
Query query = getSession().createQuery -7ct+3"J
/_,~dt
(querySentence); j %TYyL-
query.setFirstResult(page.getBeginIndex()) =[{Pw8['
.setMaxResults(page.getEveryPage()); q22cp&gmX
return query.list(); Hh;w\)/%j
} }U'5j/EFZ
V-=$:J"J'\
} ;~]&$2sk
DHt 8 f
zwU8i VDe
(%#d._j>fZ
o9wg<LP
至此,一个完整的分页程序完成。前台的只需要调用 RW(AjDM
4Bx1L+Cg
userManager.listUser(page)即可得到一个Page对象和结果集对象 Z(K [oUJx
NH'RU`U)
的综合体,而传入的参数page对象则可以由前台传入,如果用 +7 F7Kh
`4}!+fXQ
webwork,甚至可以直接在配置文件中指定。 'VJMi5Y(-
gn%#2:=pVu
下面给出一个webwork调用示例: Y1k/ngH
java代码: {]<D"x;
sQJM 4'8f
qsvUJU
/*Created on 2005-6-17*/ 3jS=
package com.adt.action.user; <Dm6CH
MP}H
5
import java.util.List; pDkT_6Q
%\~;I73
import org.apache.commons.logging.Log; )lw7W9
import org.apache.commons.logging.LogFactory; MruWt*
import org.flyware.util.page.Page; $+Pv
fQ
a
m<R!(
import com.adt.bo.Result; =~=/ d q
import com.adt.service.UserService; $elrX-(vL
import com.opensymphony.xwork.Action; Z~ ?:r
B10p7+NBF
/** )sV#
b
* @author Joa ePs<jrB<
*/ <;=Y4$y[
publicclass ListUser implementsAction{ J+IW
~7 `x9MUc
privatestaticfinal Log logger = LogFactory.getLog 2jhVmK
N7oMtlvL[w
(ListUser.class); =R>Sxaq
J.<eX=<
private UserService userService; l*v([@A\
=rBFMTllM
private Page page; 7Ck;LF}>0
}2NH>qvY
privateList users; =fsaJ@q,R
d:pp,N~2o
/* h.?[1hT4R
* (non-Javadoc) "L8V!M_e
* zl:
u@!'
* @see com.opensymphony.xwork.Action#execute() \Flq8S /t^
*/ Y43#];
publicString execute()throwsException{ Ra{B8)Q
Result result = userService.listUser(page); COHJJONR
page = result.getPage(); dlT\VWMha(
users = result.getContent(); (|[3/_!;v
return SUCCESS; }MIH{CMH
} 6\TstY3
:.35pp,0
/** [CUJ A
* @return Returns the page. ?1N0+OW
*/ y:42H tS
public Page getPage(){ 19N:9;Ixz
return page; xJ"Zg]d{
} /ruf1?\,R
6~!YEuA
/** :%>8\q>UX
* @return Returns the users. M`>W'<
*/ M:I,j
publicList getUsers(){ F}AbA pTv
return users; Cfi2N V
} z9'0&G L
9~; Ju^b
/** jSVO$AW~C
* @param page ?s?uoZ /2
* The page to set. QE #$bCw
*/ =TP>Y"
publicvoid setPage(Page page){ \
yOZ&qU
this.page = page; 4O`h%`M
} z5vryhX_Z
EmUxM_T/2
/** 7q^/.:wlf
* @param users ?+|tPjg$
* The users to set. {30<Vc=
*/ X,fTzkGj
publicvoid setUsers(List users){ p|FX_4RjX
this.users = users; O#EBR<CuK
} ZGbZu
%om7h$D=`
/** E1C8yIF
* @param userService >WDpBn:
* The userService to set. -of= Lp
*/ ('lnQD.Hd
publicvoid setUserService(UserService userService){ 7 %|>7
this.userService = userService; 19rUvgC{M
} +>3c+h,%.
} rx;U/)~#<
W" !amMQ
nB]Q^~jX
X,N@`
'" tieew
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, d+;wDu
{+[gf:Ev
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 YHA[PF
{Psj#.qP1
么只需要: \'EWur"
java代码: ~ZNhU;%YW
y?JbJ
C\; 8l}t
<?xml version="1.0"?> ^0&] .m
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 2G-?
P"4l@
1CM1u+<iZ
1.0//EN" "http://www.opensymphony.com/xwork/xwork- *nc4X9
[>:gwl
_\
1.0.dtd"> -Fdi,\e
3?XLHMxW
<xwork> 4eEs_R
&\H5*A.HkA
<package name="user" extends="webwork- ]03ZrZ!
PM
cR&xl^BJ
interceptors"> etoE$2c
iN*>Z(b"
<!-- The default interceptor stack name PGKXzp'
)2$_:Ek
--> 10J*S[n1
<default-interceptor-ref 2o$8CR;
(=/F=,w
name="myDefaultWebStack"/> v wyDY%B"n
:=Q|gRTL*
<action name="listUser" Pc7:hu
p~.@8r(
class="com.adt.action.user.ListUser"> <e^/hR4O
<param DPwSg\*)
KR}0(,Y
name="page.everyPage">10</param> 'O`3FI
<result 7&3URglsL"
U.aa iX7
name="success">/user/user_list.jsp</result> *X\c
$=*
</action> W.|6$hRl)
LasH[:QQQ
</package> [86'/:L\2
;SW-dfo2i
</xwork> ptR
;Kf|a}m -
XOCau.#
c-.>C)
#H[4?4r
XNUqZ-M:
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 [&CM-`
N
a~*V
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。 ^kr)U8
W/>?1+r.Z
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 iy]}1((hR
$3TTHS o
/;rN/ot2o
32iI :u
AD\<}/3U
我写的一个用于分页的类,用了泛型了,hoho L:M9|/
.A\ \v6@
java代码: tFaE cP
@?m8/t9.
mr!I}I7x&x
package com.intokr.util; DQ\&5ytP
Hg`{9v
import java.util.List; mM}Ukmy
!XG&=Rd?
/** @vYmkF`
* 用于分页的类<br> 'pY;]^M
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 0s|LK
* -;\+uV
* @version 0.01 QYgN39gp
* @author cheng mi<D
bnou
*/ 5}xni
public class Paginator<E> { xacLlX+
privateint count = 0; // 总记录数 #/Fu*0/)`
privateint p = 1; // 页编号 wYA/<0'yH
privateint num = 20; // 每页的记录数 Yp]G)}'R
privateList<E> results = null; // 结果 "Y]ZPFh#.
EQ7n'Wqq
/** 5j,qAay9
* 结果总数 8 %j{4$
*/ o0G`Xn
publicint getCount(){ Qc;[mxQe
return count; `4H9f&8(
} Z9 m;@<%
51
0XDl~b
publicvoid setCount(int count){ A{I
a21T7
this.count = count; -FN6sNvIh
} [
5W#1 &
9r nk\`E
/** NNwd;AC
* 本结果所在的页码,从1开始 -1
* L"h@`3o|
* @return Returns the pageNo. I#X2UQzP
*/ U%DF!~n
publicint getP(){ Bh,)5E^m
return p; IZ0$=aB7
} En9]x"_
\TB%N1^
/** SMO%sZ]
* if(p<=0) p=1 2 dD<]
* 0? us]lx
* @param p {[5L96RH%
*/ SP*JleQN
publicvoid setP(int p){ 'ZH<g8:=@
if(p <= 0) iM|"H..
p = 1; =)- Q?1q
this.p = p; qH
Ga
} ^:!(jiH
@xm~T|[7
/** {!1n5a3" 1
* 每页记录数量 g!p_c
*/ G;HlII9x[
publicint getNum(){ Qf-k&d
return num; 9G&l qfX:
} SxZ^ "\H
4A/,X>W61
/** %HF$
* if(num<1) num=1 NhoS7 y(
*/ fuD1U}c
publicvoid setNum(int num){ .Spi$>v
if(num < 1) QHzX
5$IM
num = 1;
.x!7
this.num = num; StZRc\k
} X;6r$
to!W={S<ol
/** {QS@Ugf
* 获得总页数 e#6&uFce
*/ 5uV"g5?w
publicint getPageNum(){ vvsNWA
return(count - 1) / num + 1; 6G<Hi"I
} !^l4EL5#
RpXs3=9
/** 03QEXm~|Q
* 获得本页的开始编号,为 (p-1)*num+1 #1't"R+3M
*/ cCh5Jl@Z
publicint getStart(){ an=+6lIl
return(p - 1) * num + 1; 7#9'2dI
} 380->
#
5f|1O
/** sL7`=a.&T
* @return Returns the results. BY4 R@)
*/ 5'kTe=
publicList<E> getResults(){ &&9c&xgzE
return results; A-7wkZ.H
} *%N7QyO`I
o;VkoYV
public void setResults(List<E> results){ /s8%02S
this.results = results; +/3
Z
} Kcw1uLb
;V"yMWjc
public String toString(){ o?va#/fk
StringBuilder buff = new StringBuilder CS;W)F
K_&c5(-(_
(); ]\a\6&R
buff.append("{"); \buZ?
buff.append("count:").append(count); <Sprp]n
7
buff.append(",p:").append(p); zK>'tFU
buff.append(",nump:").append(num); :%uyy5AZ
buff.append(",results:").append fa4951_
=> uVp
(results); HhWwc#B
buff.append("}"); ?|">),
return buff.toString(); }+dM1 O
} O&3r*vd
#U$YZ#B
} X&9^&U=e
w(V?N' [
Ql q#Zdru