Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 57=d;Yg e
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 g[bu9i
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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 `oH4"9&]k3
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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 s;Gg
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。 -e_op'`
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分页支持类: [cco/=c
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java代码: j9l32<h7]
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package com.javaeye.common.util; ,II3b(l
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import java.util.List; IvlfX`("
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publicclass PaginationSupport { 0{ ~2mgg h
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publicfinalstaticint PAGESIZE = 30; VBw5[
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privateint pageSize = PAGESIZE; ZO/u3&gU
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privateList items; B\e*-:pq>
9[;da
privateint totalCount; }WaZ+Mdg\
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privateint[] indexes = newint[0]; 9x|`XAB
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privateint startIndex = 0; m C`*#[
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public PaginationSupport(List items, int )Jdku}Pf
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totalCount){ w;j<$<4=7
setPageSize(PAGESIZE); >TY;l3ew
setTotalCount(totalCount); _U-`/r o
setItems(items); 0y+^{@lU
setStartIndex(0); @!u{>!~0
} +L`}(yLJ)9
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public PaginationSupport(List items, int sZT~5c8
yNowhh
totalCount, int startIndex){ Z"%.
setPageSize(PAGESIZE); euVDrJ^
setTotalCount(totalCount); 2[HPU M2>
setItems(items); GK!@|Kk8q7
setStartIndex(startIndex); 6<$.Z-,
} oBo*<6
ENIg_s4
public PaginationSupport(List items, int AvB=/p@]
nq8XVT.m^\
totalCount, int pageSize, int startIndex){ ()bQmNqmO=
setPageSize(pageSize); 2#sFY/@
setTotalCount(totalCount); [DH4iG5
setItems(items); $
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setStartIndex(startIndex); Pd\4hy
} Fa[^D~$l*
)Uy%iE*
publicList getItems(){ ]% HxzJ
return items; FHw%ynC
} Mms|jFoQ
yn_f%^!G
publicvoid setItems(List items){ -0#"<!N
this.items = items; z!O;s
ep?/
} #dL,d6a
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publicint getPageSize(){ 0NGth(2
return pageSize; z k/`Uz
} 6PYt>r&TO
W"\}##
publicvoid setPageSize(int pageSize){ 6j XDLI
this.pageSize = pageSize; n]`]gLF\i
} #IvKI+"
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publicint getTotalCount(){ 'ia-h7QWS
return totalCount; {?0'(D7.
} %UrNPk
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publicvoid setTotalCount(int totalCount){ b4-gNF]Yt
if(totalCount > 0){ SsTBjIX
this.totalCount = totalCount; 6qFzo1LO
int count = totalCount / zGR,}v%%
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pageSize; R/Bjc}J'
if(totalCount % pageSize > 0) $cHU,
count++; kY\faWuR
indexes = newint[count]; DxNob-Fr
for(int i = 0; i < count; i++){ 2Ax"X12{6
indexes = pageSize * Rw{'
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i; bE.<vF&
} 4@3 \Ihv
}else{ c-(RjQ~M5
this.totalCount = 0; H'zAMGZa
} #p>&|I
} K~,!IU_QG
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publicint[] getIndexes(){ l`zhKj
return indexes; x\8g ICf
} 4X]/8%]V
Ja:4EU$Lu
publicvoid setIndexes(int[] indexes){ Os-Z_zSl6
this.indexes = indexes; JX&]>#6|E
} SNOc1c<~
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publicint getStartIndex(){ o#\L4P(J
return startIndex; ~*/ >8R(Y
} +_J@8k
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publicvoid setStartIndex(int startIndex){ UX63BA
if(totalCount <= 0) fc@<' -VA
this.startIndex = 0; XjN=UhC
elseif(startIndex >= totalCount) klnNBo!
this.startIndex = indexes
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9)v]jk
[indexes.length - 1]; v)_c*+6u
elseif(startIndex < 0) jn|NrvrX
this.startIndex = 0; GqL&hbpi
else{ 5@%Gq)z5
this.startIndex = indexes `aAE4Ry?
Zt!$"N.,
[startIndex / pageSize]; e8("G[P>
} Z,2?TT|p
} @[9
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publicint getNextIndex(){ }.)R#hG?
int nextIndex = getStartIndex() + >8I~i:hn
3]?='Qq.(
pageSize; Ebs]]a>PO
if(nextIndex >= totalCount) "zJ xWXI
return getStartIndex(); Jw}t~m3
else a5/, O4Q
return nextIndex; fVgK6?<8^
} }Y.YJXum
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publicint getPreviousIndex(){ WUie`p
int previousIndex = getStartIndex() - DCiU?u~
aSIb0`(3
pageSize; C]mp<
if(previousIndex < 0) i=#\`"/
return0; -@>]iBl
else WLXt@dK*u
return previousIndex; XLpn3sX$
} L;")C,CwQ
*uRDB9#9,
} E*5aLT5!,
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"r@#3T$
抽象业务类 A"M;kzAfHM
java代码: z_xy*Iif
qzxWv5UH
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/** k8}fKVU;
* Created on 2005-7-12 ASoBa&vX
*/ a. D cmy{
package com.javaeye.common.business; W?zj^y[w
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import java.io.Serializable; <}~
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import java.util.List; Tdh.U{Nz
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import org.hibernate.Criteria; 8Gy]nD
import org.hibernate.HibernateException; bS8$[7OhX
import org.hibernate.Session; h )Y.jY
import org.hibernate.criterion.DetachedCriteria; y|O3*`&m
import org.hibernate.criterion.Projections; liPrxuP`
import L@[}sMdq(
V)~b+D
org.springframework.orm.hibernate3.HibernateCallback; 3l~7
import [C4{C4TX
q[qX O5
org.springframework.orm.hibernate3.support.HibernateDaoS nw/g[/<;
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upport; 6/wC StZ
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import com.javaeye.common.util.PaginationSupport; <`SA>P
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public abstract class AbstractManager extends Vbp@n
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HibernateDaoSupport { n%36a(]
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privateboolean cacheQueries = false; 2
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privateString queryCacheRegion; ],!}|
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publicvoid setCacheQueries(boolean ZKt{3P
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cacheQueries){ J)Yz@0#T(;
this.cacheQueries = cacheQueries; Hfj.8$
} nX7F<k4G2
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publicvoid setQueryCacheRegion(String y{(Dv}
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queryCacheRegion){ C~>0K,C0^
this.queryCacheRegion = Adiw@q1&
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queryCacheRegion; C3=0st$
} Dj=$Q44
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publicvoid save(finalObject entity){ :dipk,b?n
getHibernateTemplate().save(entity); mm#UaEp
} ux^rF
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publicvoid persist(finalObject entity){ jt6_1^
getHibernateTemplate().save(entity); 1
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} &k*oG:J3
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publicvoid update(finalObject entity){ )g8Kicox5
getHibernateTemplate().update(entity); ;>ml@@Z
} b (HJ|
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publicvoid delete(finalObject entity){ _M8'~$Sg
getHibernateTemplate().delete(entity); EVqqOp1$v4
} au=@]n#<(
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publicObject load(finalClass entity, 6X'0 T}
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finalSerializable id){ Xajt][
return getHibernateTemplate().load |ul{d|
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(entity, id); fA1{-JzV<4
} VPO~veQ
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publicObject get(finalClass entity, M7Xn=jc
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finalSerializable id){ zI^:{]p
return getHibernateTemplate().get UT{`'#iT
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(entity, id); dlZ2iDQ%
} 8.wtv5eZ
}vP(SF6
publicList findAll(finalClass entity){ "tJ[M
return getHibernateTemplate().find("from t}}Ti$$>
\O~/^ Y3U!
" + entity.getName()); 73u97oe>1
} mcQ
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}3WP:Et
publicList findByNamedQuery(finalString Jc]k\U
SCn)j:gH;
namedQuery){ Vy/G-IASb
return getHibernateTemplate $mAyM+ ph[
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().findByNamedQuery(namedQuery); /9SoVU8
} \AI-x$5R*
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publicList findByNamedQuery(finalString query, ZjY?T)WE9
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finalObject parameter){ lOb(XH9
return getHibernateTemplate -+2A@kmEJ
4%<wxrod
().findByNamedQuery(query, parameter); G[`2Nd<
} PD^ 6Ywn>s
eq"Xwq*
publicList findByNamedQuery(finalString query, vqoK9
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finalObject[] parameters){ }{PG^ Fc<P
return getHibernateTemplate icVB?M,m
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().findByNamedQuery(query, parameters); 3,hu3"@k
} ]M "U 'Z
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publicList find(finalString query){ KT(v'KE 1
return getHibernateTemplate().find w4Hq|N1-Y
:T@} CJ
(query); )Xt#coagS
} c%wztP;L
jc!V|w^
publicList find(finalString query, finalObject LV$Ko_9eA
'vq0Tw5
parameter){ Ed-3-vJej6
return getHibernateTemplate().find g#1Y4
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(query, parameter); Ms3GvPsgv
} s6}SdmE
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public PaginationSupport findPageByCriteria {5ehm
B=r+
m;(
(final DetachedCriteria detachedCriteria){ ;>5]KNj
return findPageByCriteria Dequ'
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); $Dv5TUKw
} 9`H4"H>yG
OYmutq
public PaginationSupport findPageByCriteria ]70ZerQ~L
&VCg`r-{~
(final DetachedCriteria detachedCriteria, finalint ESFJN}Q%0.
v/v PU
startIndex){ F]<2nb7
return findPageByCriteria V`c,U7[/
Ut/%+r"s
(detachedCriteria, PaginationSupport.PAGESIZE, .>}Z3jUrf
8y[Rwa
startIndex); Jko=E
}
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public PaginationSupport findPageByCriteria '<e$ c
qf@P9M
(final DetachedCriteria detachedCriteria, finalint vwa*'C
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pageSize, W|sU[dxZ
finalint startIndex){ (?GW/pLK]
return(PaginationSupport) 1BP/,d |+
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getHibernateTemplate().execute(new HibernateCallback(){ 7dE.\#6r
publicObject doInHibernate ![I|hB
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(Session session)throws HibernateException { LU@1Gol
Criteria criteria = ]vV)$xMX
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detachedCriteria.getExecutableCriteria(session); B
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int totalCount = 1TGE>HG
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((Integer) criteria.setProjection(Projections.rowCount 3U!=R-
|S<!'rY
()).uniqueResult()).intValue(); gg#lI|
criteria.setProjection DH i@ujr
79o=HiOF99
(null); g "c7$
List items = 2BT+[
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criteria.setFirstResult(startIndex).setMaxResults im)r4={
9
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(pageSize).list(); v:w^$]4
PaginationSupport ps = NMC0y|G
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new PaginationSupport(items, totalCount, pageSize, t0/Ol'kgs
cBOt=vg,5
startIndex); 4?
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return ps; ,Qo:]Mj
} :v$)Z~
}, true); ,iZKw8]f
} c7WOcy@M
,":_CY4(
public List findAllByCriteria(final '*@=SM
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DetachedCriteria detachedCriteria){ \O,yWyU4
return(List) getHibernateTemplate q['3M<q
}5$le]
().execute(new HibernateCallback(){ /L|x3RHs
publicObject doInHibernate TT#V'r\
J*:_3Wsy
(Session session)throws HibernateException { 497 l2}0
Criteria criteria = qwn EVjf
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detachedCriteria.getExecutableCriteria(session); [T/S/@IT
return criteria.list(); S+^hK1jL
} m*i,|{UZ
}, true); Imclz4'8
} +br'
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public int getCountByCriteria(final #e@[{s7
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DetachedCriteria detachedCriteria){ i3$G)W
Integer count = (Integer) +t
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getHibernateTemplate().execute(new HibernateCallback(){ c]$$ap
publicObject doInHibernate J{XRltI+
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(Session session)throws HibernateException { Ri::Ek3qu
Criteria criteria = OI6m>XH?
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detachedCriteria.getExecutableCriteria(session); J'WOqAnPZ
return =`CK`x
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criteria.setProjection(Projections.rowCount K_.|FEV
*;F<Q!i&v
()).uniqueResult(); LFYSur8
} GyFA1%(o
}, true); \~U:k4
return count.intValue(); e~R_ bBQ0
} 1C*mR%Q
} YZ<5-C
-?IF'5z
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x>A[~s"|N
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用户在web层构造查询条件detachedCriteria,和可选的 Q?`s4P)14o
D})12qB;u9
startIndex,调用业务bean的相应findByCriteria方法,返回一个 \SYeDy
.>-D{
PaginationSupport的实例ps。 2Ib
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ps.getItems()得到已分页好的结果集 ^i3!1cS
ps.getIndexes()得到分页索引的数组 aJ1{9 5ea
ps.getTotalCount()得到总结果数 d+0= a]
ps.getStartIndex()当前分页索引 W58%Zz4a
ps.getNextIndex()下一页索引 A
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ps.getPreviousIndex()上一页索引 I58$N+#
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8&qtF.i-6
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6J$I8b#/
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 _?I*::
I
34_
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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 <R_)[{ 7
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一下代码重构了。 U5?QneK
t23W=U
我把原本我的做法也提供出来供大家讨论吧: ^L.'At
cveQ6
-`K
首先,为了实现分页查询,我封装了一个Page类: ?k^m|Z
java代码: :}gEt?TUhs
ZcTjOy?
[ThAvQ_$
/*Created on 2005-4-14*/ L EFLKC
package org.flyware.util.page; xv%]g=Q
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/** W}%[i+
* @author Joa 6%wlz%Fp
* "t-9q
*/ ^B7Ls{
publicclass Page { 'S&Zq:
~HKzqGQy>
/** imply if the page has previous page */ %8YUK/(|n
privateboolean hasPrePage; '0I>
um( xZ6&m
/** imply if the page has next page */ O+=}x]q*y
privateboolean hasNextPage; z('t#J!b
|~rKD c
/** the number of every page */ {yd(n_PqY
privateint everyPage; qc';<
HTm`_}G9
/** the total page number */ O+[s4]
privateint totalPage; 4#ikdjB;
}` <DKO/
/** the number of current page */ )YwLj&e4tf
privateint currentPage; oP:R1<
QDb8W*&<
/** the begin index of the records by the current ?_T[]I'
g+?2@L$L
query */ \,lIPA/L
privateint beginIndex; ;(K"w*
,<s:*
k
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/** The default constructor */ k_gl$`A
public Page(){ >CHb;*U
T?tZ?!6
} la^K|!|
mDuS-2G=D
/** construct the page by everyPage # 00?]6`z
* @param everyPage {V8uk$
* */ u?'J1\z
public Page(int everyPage){ p$*P@qm
this.everyPage = everyPage; 4jjo%N
} }I18|=TB
J(P'!#z^
/** The whole constructor */ :"
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public Page(boolean hasPrePage, boolean hasNextPage, PM&NY8|Zy
^_W] @m2
j^h:*rw
int everyPage, int totalPage, J'k^(ZZ
int currentPage, int beginIndex){ 8VC%4+.FF
this.hasPrePage = hasPrePage; sN MF(TY
this.hasNextPage = hasNextPage; S?c<Lf~W
this.everyPage = everyPage; f=7[GZoDn
this.totalPage = totalPage; ,8!'jE[d
this.currentPage = currentPage; = U[$i"+
this.beginIndex = beginIndex; H%i [;
} u
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8CH9&N5W5t
/** 6#a82_
* @return C+dz0u3s
* Returns the beginIndex. 'X?Iho
*/ JLg/fB3%
publicint getBeginIndex(){ OAgZeK$
return beginIndex; )XoMOz
} k3]qpWKj
Q"3gvIyc
/** z>'vS+axV
* @param beginIndex =CjWPZShV
* The beginIndex to set. ~w.y9)",
*/ 8~BLTZ
publicvoid setBeginIndex(int beginIndex){ |A+,M"F?
this.beginIndex = beginIndex; J- 5kvQi8
} e-VGJxR
wT-Kg=-q
/** 0}'/3Q
* @return K%u>'W
* Returns the currentPage. v`p@djM
*/ +Z]}ce
u"
publicint getCurrentPage(){ 4i<GqG
return currentPage; #wkSru&LS
} ZQ' |B
hb9HVj
/** 0vMKyT3 c
* @param currentPage SEE:v+3|
* The currentPage to set. NW&2ca
*/ as!P`*@
publicvoid setCurrentPage(int currentPage){ GXRW"4eF5
this.currentPage = currentPage; sN) xNz
} (.5Ft^3W
<vb7X
/** uWP0(6 %
* @return BaMF5f+
* Returns the everyPage. >ZU)bnndA
*/ [<d_#(]h'
publicint getEveryPage(){ /Kd'!lMuz
return everyPage; Y)#,6\=U
} a :cfr*IsK
YtXd>@7
/** tGSXTF}G
* @param everyPage ][XCpJ)8
* The everyPage to set. 5@pLGMHT
*/ ?D(aky#cyc
publicvoid setEveryPage(int everyPage){ voJJoy%
this.everyPage = everyPage; 7I;0%sVQ{
} O[p c$Pi
AOz~@i^
/** +4Q1s?`
* @return 7;Vmbt9
* Returns the hasNextPage. '?LqVzZI
*/ S,a:H*Hf
publicboolean getHasNextPage(){ IOJLJ
p
return hasNextPage; =?N$0F!
} 6}Rb-\N
}%^ 3
/** c6iFha;db
* @param hasNextPage ^g.HJQ'vF
* The hasNextPage to set. P0k.\ 8qz
*/ Os!x<r|r
publicvoid setHasNextPage(boolean hasNextPage){ 1@F>E;YjL=
this.hasNextPage = hasNextPage; X?(R!=a
} "I @akM$x
-KZ9TV # R
/** u(PUbxJ
V
* @return xlh<}Vtp
* Returns the hasPrePage. K~fWZT3]
*/ xU(b:D Z
publicboolean getHasPrePage(){ st >%U9
return hasPrePage; \tP*Pz
}
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n]>L"D,
/** |3hNTH?
* @param hasPrePage Ix~rBD9
* The hasPrePage to set. mcs!A/]<
*/ LC e6](Z
publicvoid setHasPrePage(boolean hasPrePage){ 57_AJT hR
this.hasPrePage = hasPrePage; Iv u'0vF
} Wq?vAnLbk
<oSx'_dc
/** Jyp7+M]
* @return Returns the totalPage. QT|\TplJt
* Z!4B=?(
*/ J~h9i=4<bF
publicint getTotalPage(){ H|'n|\{lt
return totalPage; Y^XZ.R
} O:8Ne*L`D
e+?;Dc-SJ\
/** tJm1Q#||
* @param totalPage ):n'B` f}z
* The totalPage to set. 3-)R'
*/ gf^y3F[\
publicvoid setTotalPage(int totalPage){ c(!pcB8
this.totalPage = totalPage; b=SCyGxlZ5
} q2;CvoF
.k%/JF91n
} 98vn"=3
Hr \vu`p$
:!FGvR6
@ *5+ZAF
v"<M
~9T)
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 n1b^o~agwC
Ql,WKoj*
个PageUtil,负责对Page对象进行构造: <@y(ikp>
java代码: `X B$t?xi
3ik~PgGoKQ
}|nEbM]#
/*Created on 2005-4-14*/ at\$
IK_
package org.flyware.util.page; urQ<r{$x0
zXkq2\GHA
import org.apache.commons.logging.Log; &egP3
import org.apache.commons.logging.LogFactory; i1 GQ=@
we
kb&?
/** Fz| r[
* @author Joa 6p.y/LMO
* ^,J>=>,1\
*/ 29&F_
publicclass PageUtil { Bp4#"y2
l-SVI9|<0
privatestaticfinal Log logger = LogFactory.getLog 4y$okn\}i
|lyspD
(PageUtil.class); 5D mSgP:
/2 qxJvZ
/** G{zxP%[E
* Use the origin page to create a new page bzZ7L-yD
* @param page y`cL3
xr4R
* @param totalRecords VmZDU(M
* @return )"63g
*/ m]}EVa_I`/
publicstatic Page createPage(Page page, int pezfB{x?
PK&X |
h
totalRecords){ ]1I-e2Q-J
return createPage(page.getEveryPage(), OUN"'p%%
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page.getCurrentPage(), totalRecords); }|RL6p-/'
} m&[(xVM
(v$
i
/** Qz$Wp*
* the basic page utils not including exception _P%PjFQ)
\7e4t
handler KYq<n& s
* @param everyPage 0;%\L :,O
* @param currentPage ; NO#/
* @param totalRecords x6vkd%fCj
* @return page c]|Tg9AW
*/ ojVN-*5
publicstatic Page createPage(int everyPage, int ;)ERxMun
sGa "
currentPage, int totalRecords){ VS65SxHA
everyPage = getEveryPage(everyPage); BU|m{YZ$
currentPage = getCurrentPage(currentPage); /)4Q%Zp
int beginIndex = getBeginIndex(everyPage, {&FOa'bP
@2>ce2+
currentPage); ]#r Nz"
int totalPage = getTotalPage(everyPage, ^GiWU +`
'G`xD3 E3,
totalRecords); V h5\'Sn
boolean hasNextPage = hasNextPage(currentPage, gA 19f
x$pz(Q&v
totalPage); _6]tbni?v
boolean hasPrePage = hasPrePage(currentPage); bvT$/(7
`u8(qGg7GF
returnnew Page(hasPrePage, hasNextPage, r'@7aT&_
everyPage, totalPage, bKh}Y`
currentPage, ft!D2M
<<9|*Tz
beginIndex); )[=C@U
} {l\Ep=O vx
-:Q"aeC5
privatestaticint getEveryPage(int everyPage){ N_(-\\mq
return everyPage == 0 ? 10 : everyPage; VuH}@
} tn |H~iF{
khQfLA
privatestaticint getCurrentPage(int currentPage){ `'pfBVBz
return currentPage == 0 ? 1 : currentPage; eGWwPSIp
} "M,Hm!j
=~q$k
privatestaticint getBeginIndex(int everyPage, int
`Y,Rk
NYR:dH]N~d
currentPage){ 6~6 vwp
return(currentPage - 1) * everyPage; xSq+>, b
} )H&ZHaO,_
}x_:v!G
privatestaticint getTotalPage(int everyPage, int {H
3wL
.EjjCE/v-
totalRecords){ DH.CAV
int totalPage = 0; zXe]P(p<
0bu!(Tpg7
if(totalRecords % everyPage == 0) qR4-~p8
totalPage = totalRecords / everyPage; vI(CX]o
else *QoQ$alHH
totalPage = totalRecords / everyPage + 1 ; C
*7x7|z
9q2x}
return totalPage; Seq
^o=
} ]DZ~"+LaG
0 n|>/i
privatestaticboolean hasPrePage(int currentPage){ [9yy<Z5
return currentPage == 1 ? false : true; 1=^|
} ayN[y
LVy (O9g
privatestaticboolean hasNextPage(int currentPage, 6g)CpZU
8w~X4A,
int totalPage){ =
jTC+0u
return currentPage == totalPage || totalPage == .la_u8A]
w(Q{;RNM;
0 ? false : true; }RQHsS
} SOS|3q_`
r4]hcoU
/5?tXH"
} ~^o YPd52*
m;vm7]5
l_ LH!Tu
ZtpbKy!\$B
"}0)~,{xB
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。 ];QX&";Z
NH'QMjL)
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 {$C"yksr
l4^MYwFR{O
做法如下: pO2XQYhrY
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 Zy>y7O(,
M2A_T.F=H
的信息,和一个结果集List: sDkO!P
java代码: TR:4$92:H
WKq{g+a
^KQZ;[B
/*Created on 2005-6-13*/ :=K+~?
package com.adt.bo; gbu)bqu2x
mqiCn]8G
import java.util.List; =3GgfU5k
~;oaW<"
import org.flyware.util.page.Page; ra1_XR}
{G=|fgz
/** ?%b#FXA
* @author Joa +rKV*XX@
*/ zOis}$GR
publicclass Result { Z
jXn,W]~
eX'V#K#C
private Page page; Qgq VbJP"
|sAl k,8s
private List content; !@FzP@
X6r3$2!
/** ,oJ$m$(Lj
* The default constructor 2rM/kF >g
*/ IG!(q%Gf
public Result(){ AzSmfEaU0
super(); {7EpljH@
} w%%*3[--X
J #;|P-pt
/** H9[0-Ur5
* The constructor using fields @$;I%
* 0fN;
L;v
* @param page 26=G%F6
* @param content } ;d=
*/ |[$TT$Fb
public Result(Page page, List content){ OS=~<ba
this.page = page; +]e) :J
this.content = content; caL\ d
} a*nCvZ
wKbU}29c
/** 8,)<,g-/=
* @return Returns the content. )vGxF}I3
*/ O*>`md?MH
publicList getContent(){ perhR!#J
return content; 9e;:(jl^
} D*g
K, `
w$jSlgUHy)
/** :bqUA(k
* @return Returns the page. HHT8_c'CC#
*/ ,9$| "e&
public Page getPage(){ ?',GR aD
return page; !fJy7Y
} , Q )
x}uDW
/** p uW
* @param content
4G j
* The content to set. Fh}GJE
*/ !_-Uwg
public void setContent(List content){ H@sM$8
this.content = content; MwaRwk;
} FW3uq^
D=M'g}l
/** (bD#PQXzm
* @param page ?BU?c:"f
* The page to set. oKPG0iM:
*/ RAA,%rRhu(
publicvoid setPage(Page page){ _lfS"ae
this.page = page; lr)9 U7
} cvjZ$Fcc%(
} .qCI!%fg
Tz7|OV_W$
i4)]lWnd
FaKZ|~Y
e
<'~6L#>,<
2. 编写业务逻辑接口,并实现它(UserManager, "7w=LhzV[$
'T]Ok\
UserManagerImpl) %<MI]D
java代码: HE+D]7^
PVrNS7 Rk/
q,=YKw)*
/*Created on 2005-7-15*/ /mK]O7O7
package com.adt.service; &
z5:v-G?
dA0o{[o=
import net.sf.hibernate.HibernateException; fjm3X$tR
Y0ACJ?|
import org.flyware.util.page.Page; l7(p~+o?h>
QiNLE'19^
import com.adt.bo.Result; UGP&&A#T-
it->)?"(6
/** J>fq5
* @author Joa CT(HTu
*/ Wli!s~c5Fo
publicinterface UserManager { m(CsO|pz
N"zl7 .E
public Result listUser(Page page)throws L8KaK
CUj$ <ay=
HibernateException; u|(Iu}sE=
b\H,+|iK
} J4?SC+\
xj JoWB
VI)hA
^S
/$j,p E=
z h%b<
java代码: fbkAu
f2k~(@!h
DKG;up0
/*Created on 2005-7-15*/ ;bFd*8?;
package com.adt.service.impl; ~l*[=0}
QfL8@W~e
import java.util.List; )ZpMB
uC2qP)m,^
import net.sf.hibernate.HibernateException; DN;$->>
9+~1# |
import org.flyware.util.page.Page; kE1k@h#/
import org.flyware.util.page.PageUtil; +[pJr-k
)2R]KU_=g
import com.adt.bo.Result; srH.$Y;~
import com.adt.dao.UserDAO; /1.gv~`+
import com.adt.exception.ObjectNotFoundException; Kj:'Ei7
import com.adt.service.UserManager; NFI~vkk'G
7Kti&T
/** a)!R4
* @author Joa (mx}6A
*/ !ozHS_
publicclass UserManagerImpl implements UserManager { 9 $zx<O
vyT-!mC
private UserDAO userDAO; $LtCI
>n%ckL|rG
/** Ee=!bv(%70
* @param userDAO The userDAO to set. iGNZC{
*/ 1:4u]$@E
publicvoid setUserDAO(UserDAO userDAO){ h#uk-7
this.userDAO = userDAO; Cm-dos
} h2
>a_0"
1JZhcfG
/* (non-Javadoc) x/%/MFK)>8
* @see com.adt.service.UserManager#listUser _;:B@Z
^vTp.7o~5
(org.flyware.util.page.Page) .xtam 8@
*/ 4!Lj\.!$
public Result listUser(Page page)throws * K0aR!
2 y&k
HibernateException, ObjectNotFoundException { f5'vjWJ30
int totalRecords = userDAO.getUserCount(); :* J!
if(totalRecords == 0) +<WNAmh
throw new ObjectNotFoundException Z;6?,5OSc
`(~oZbErM
("userNotExist"); 4cDe'9
LA
page = PageUtil.createPage(page, totalRecords); b>nwX9Y/U
List users = userDAO.getUserByPage(page); T|uG1
returnnew Result(page, users); .<6'*XR
} ZJHaY09N
J?f7!F:8
} J n'SGR
u`u{\
xN9
^h"@OEga?
c`7 dNx
PsN_c[+
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 nsu RG
JC7:0A^
询,接下来编写UserDAO的代码: H)5" <=]
3. UserDAO 和 UserDAOImpl: ?F|F~A8dr
java代码: 5zH_yZ@+
3/8<dc
Y5<W"[B!
/*Created on 2005-7-15*/ :%IB34e
package com.adt.dao; ^-(DokdBn
8#RL2)7Uy`
import java.util.List; x(A6RRh
{Bb:\N8X
import org.flyware.util.page.Page; 2FEi-m}
w+hpi5OH
import net.sf.hibernate.HibernateException; M/YS%1
(.kzJ\x
/** HaQox.v%
* @author Joa _BG7JvI
*/ fj[Kbo 7!h
publicinterface UserDAO extends BaseDAO { [!`5kI
Zl?9ibm;@
publicList getUserByName(String name)throws ,
jCE
hb
kk}_AZ0eK
HibernateException; A1B%<$|pz
E|_}?>{R
publicint getUserCount()throws HibernateException; BxB B](
zEw~t&:e
publicList getUserByPage(Page page)throws Sp[]vm8N
2FR5RG
oD
HibernateException; gN[^ ,u
H"wIa8A
} Rp6q)
=|H.r9-PK6
V2$M`|E
'|G8yojz
[x
-<O:r=P
java代码: {N@Pk[!
rW`l1yi*$
Xi!e=5&Pa
/*Created on 2005-7-15*/ ~Sx\>wBlc
package com.adt.dao.impl; 6ck%M#v
6u{%jSA>D\
import java.util.List; dyB@qh~H
i$CF*%+t
import org.flyware.util.page.Page; ;dTxQ_:
&5hs
W1`
import net.sf.hibernate.HibernateException; Uv!VzkPfo
import net.sf.hibernate.Query; rv2;)3/*
v(P <_}G
import com.adt.dao.UserDAO; m1M6N`f
6+:;Mb_S
/** 8qoA5fW>
* @author Joa z<8VJZd
*/ Ei89Ngp\}
public class UserDAOImpl extends BaseDAOHibernateImpl 3Qu-X\
D0h6j0r5
implements UserDAO { C{,Vk/D-0
T75N0/teS
/* (non-Javadoc) 4K,S5^`Gx
* @see com.adt.dao.UserDAO#getUserByName $}=r45e0K
M%7|7V<o)^
(java.lang.String) AsI.8"
*/ JI/iq
publicList getUserByName(String name)throws 6#HnA"I2n
3!i{4/
HibernateException { {"db1Gbfg
String querySentence = "FROM user in class kA9 k^uR/
w7f)v\p
com.adt.po.User WHERE user.name=:name"; 2%)~E50U
Query query = getSession().createQuery @)@tIhw
){KrBaGa4
(querySentence); o Va[
query.setParameter("name", name); bl\;*.s'
return query.list(); :bXTV?#0
} t|*UlTLm
G^#?~
/* (non-Javadoc) o8SP#ET"n
* @see com.adt.dao.UserDAO#getUserCount() \p!m/2
*/ l|M|;5TW
publicint getUserCount()throws HibernateException { }Ggn2 X
int count = 0; _WI~b
String querySentence = "SELECT count(*) FROM ZHCrKp
iDYm4sY
user in class com.adt.po.User"; (R(NEN
Query query = getSession().createQuery Bk5ft4v-
i*mI-l
(querySentence); Q+Eqaz`
count = ((Integer)query.iterate().next =nlj|S ~3
,_K:DSiB
()).intValue(); Uh'W d_?
return count; >2NsBS(
} Fzz9BEw(i
& d* bQv$
/* (non-Javadoc) UU '9
* @see com.adt.dao.UserDAO#getUserByPage Y]i:$X]C?X
W9{y1,G9
(org.flyware.util.page.Page) z2q!_ ~
*/ kH=qJ3Z
publicList getUserByPage(Page page)throws /9| 2uw`
@.pr}S/
HibernateException { 4I2#L+W
String querySentence = "FROM user in class r>G||/Z
R S] N%`]
com.adt.po.User"; kD6Iz$tr
Query query = getSession().createQuery wV,=hMTd&\
qJw\<7m
(querySentence); 2FGCf} ,
query.setFirstResult(page.getBeginIndex()) milQxSpj
.setMaxResults(page.getEveryPage()); e'|c59E
return query.list(); %h
v-3L#V
} R9UC0D:-x
V=c?V/pl
} m~F ~9&
0\+$j5;
ac8su0
4x.I"eW~&
lE3&8~2
至此,一个完整的分页程序完成。前台的只需要调用 7r pTk&`
sR| /s3;
userManager.listUser(page)即可得到一个Page对象和结果集对象 biVsbxYurq
Gi&/`vm
的综合体,而传入的参数page对象则可以由前台传入,如果用 6L2Wv5C
E&Sr+D aPD
webwork,甚至可以直接在配置文件中指定。 @==
"$uRw
z]j_,3Hff
下面给出一个webwork调用示例: A$?o3--#]G
java代码: TBgiA}|\D
fqn;,!D?9
g^^^fKUp )
/*Created on 2005-6-17*/ b)T6%2
package com.adt.action.user; ~}Z{hs)
B&}lYo
import java.util.List; @FN1o4&3
iu{QHjZK(
import org.apache.commons.logging.Log; lLEEre
import org.apache.commons.logging.LogFactory; 8_3WCbe/
import org.flyware.util.page.Page; h9rrkV9
?l`|j*
import com.adt.bo.Result; \*c=bz&l
import com.adt.service.UserService; s*vtCdrE.
import com.opensymphony.xwork.Action; .C1g Dry]
pWKI^S
/** AS lmW@/9v
* @author Joa ~)5k%?.
*/ sO)!}#,
publicclass ListUser implementsAction{ zhU^~4F
.G|U#%"6x
privatestaticfinal Log logger = LogFactory.getLog o^u}(wZ{
=E&1e;_xlE
(ListUser.class); e(9K.3@{
e{.P2rnh
private UserService userService; xP 3>8Y
> Qh#pn*
private Page page; -U@ycx|r
UiZ1$d*
privateList users; ?y^ ix+M
IOl0=+p
/* y <P1VES
* (non-Javadoc) `Vh&XH\S
* ;\iu*1>Z,&
* @see com.opensymphony.xwork.Action#execute() @! jpJ}
*/ Y }8HJTMB
publicString execute()throwsException{ DhG{hQ[[
Result result = userService.listUser(page); @>[3[;
page = result.getPage(); B:)vPO+ d
users = result.getContent(); %3q7i`AZ
return SUCCESS; RR>G}u9np
} M,SIs
3
^_o:Ddz?l"
/** = Ruq
* @return Returns the page. !1P<A1K
*/ t0)hdX
public Page getPage(){ mm N$\2
return page; 5(y Q-/6C+
} ~bfjP2
g
l{.
XhB
/** #twl
* @return Returns the users. xic&m5j
m
*/ Q5;EQ.#
publicList getUsers(){ #}8gHI-9%
return users; mMad1qCi7
} 5
Praj
>F/5`=/'h
/** j7C&&G q
* @param page 8HdjZ!
* The page to set. ,m)YL>k
*/ ~uJO6C6A
publicvoid setPage(Page page){ i\\,Z
L
this.page = page; MUp{2_RA
} /fxv^C82yv
-yY]0
/** ?gS~9jgcd
* @param users u~27\oj,
* The users to set. CePI{`&,
*/ }do=lm?/
publicvoid setUsers(List users){ 7[(<t+
this.users = users; HE3x0H}o>
} Il!#]
tEllkHyef
/** Q_A?p$%;L
* @param userService It8@Cp.dU
* The userService to set. &P>a
*/ R?l={N=Wf
publicvoid setUserService(UserService userService){ YuzgR;Z
this.userService = userService; L%4Do*V&
} Mj:=$}rs^
} s=)1:jYk
g]}E1H6-
>\ PNKpn{
y!kM#DC^
N#vV;
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, ;3N>m|?D=
m H&WoL<K
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 h?&S*)1
[\)irCDv
么只需要: gOn^}%4.I
java代码: (%|L23
Tv~Ys#
XNB4KjT
<?xml version="1.0"?> CGCSfoS9f
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork I)f54AX
gK-$y9]~+
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 4:qM'z
P\.1w>X
1.0.dtd"> O%busM$P)/
'U4@Sax,
<xwork> F0+@FS0
bOdyrynh
<package name="user" extends="webwork- %hb!1I
/PtmJ2[
interceptors"> <,(Ww
yyuf
<!-- The default interceptor stack name 8,&QY%8pX
Z~ {[YsG
--> R>`TV(W`9
<default-interceptor-ref F$H^W@<w
OEj%cB!
name="myDefaultWebStack"/> 7a'@NgiGg
m*H6\on:
<action name="listUser" aZYs?b>Gm
mX
QVL.P\
class="com.adt.action.user.ListUser"> iC Z1ARi
<param ~er4w+"
OwG:+T_
name="page.everyPage">10</param> (Qz|
N
<result 8nHFNOv6
9y5nG
name="success">/user/user_list.jsp</result> >tVD[wVF0
</action> -nC!kpo
-$5nqaK?
</package> ? Glkhf7(
Lw #vHNf6
</xwork> aG/L'weR
aT%6d@g
4Nz]LK%@
\J3n[6;
K@+(6\6I
rJ_fg$.<
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 gAViwy9{
zu|=1C#5h
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。 /,#&Htk
:TN^}RML
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 {,b:f
;l2pdP4jf
pbb6?R,
F5;x>;r
\H$j["3
我写的一个用于分页的类,用了泛型了,hoho %4HpTx
V/i7Z h#2:
java代码: vd!|k5t[d
$Xr9<)?,
]{'lV~fc
package com.intokr.util; 4?9cyv4H
4+_r0
import java.util.List; }@S''AA\
:6X?EbXhK
/** L
BP|
* 用于分页的类<br> (3M7 RpsL@
* 可以用于传递查询的结果也可以用于传送查询的参数<br> U `<?~Bz
* \%011I4
* @version 0.01 S)[$F}
* @author cheng ^\zf8kPti
*/ Um\_G@
public class Paginator<E> { A/{0J\pA
privateint count = 0; // 总记录数 -
d(RK_
privateint p = 1; // 页编号 CNF3".a
privateint num = 20; // 每页的记录数 L;s,x V
privateList<E> results = null; // 结果 $6p|}<u
B\}B
H
/** 5(sWV:_2
* 结果总数
V;-YM W
*/ gzDNMM
publicint getCount(){ @G;\gJT*
return count; 2
.)`8|c9
} "vG~2J
-THU5AB
publicvoid setCount(int count){ FlQ(iv)P
this.count = count; }c~o3t(7`b
} -%#F5br%
"G3zl{?GP
/** B'"RKs]
* 本结果所在的页码,从1开始 5Myp#!|x:
* 8h| 9;%
* @return Returns the pageNo. O'}
%Bjl
*/ C7lBK<gQ
publicint getP(){ %1oG<s
return p; $9Yk]~
} 17{$D,P
4(FEfde=
/** jvfQG:F }
* if(p<=0) p=1 4S+sz?W2j
* #b?)fqRJL
* @param p jsrIZbN
*/
:pZWFJ34{
publicvoid setP(int p){ @on\@~Ug
if(p <= 0) 7v^V]&&s
p = 1; ~)\E&c
this.p = p; 4q7hL
} 4]$$ar)
8hx 3pvmk
/** Rg?m$$X`
* 每页记录数量 ~9KxvQzt
*/ 1-M\K^F
publicint getNum(){ "dO>P*k,
return num; Hkck=@>8H*
} rFPfTpS
\h}a?T6
/** P,@ :?6
* if(num<1) num=1 $rG~0
*/ GE{u2<%@
publicvoid setNum(int num){ atA:v3"
if(num < 1) s,|s;w*.
num = 1; ~Uz1()ftz
this.num = num; ,B=;NKo
} sjISVJ?
Z7t-{s64
/** 0=^A{V!m
* 获得总页数 M>BcYbXf
*/ }JKK"d}U
publicint getPageNum(){ BCK0fk~
return(count - 1) / num + 1; 4pfv?!Oj
} 5@xl/
;%H/^b.c
/** K !MIA
* 获得本页的开始编号,为 (p-1)*num+1 |tkhsQ-;
*/ *j0kb"#
publicint getStart(){ LYv$U;*+
return(p - 1) * num + 1; b\l +S2
} `Ko6;s#
rcWr0q
/** Jm l4EW7
* @return Returns the results. (\=iKE4#
*/ k5%:L2FO
publicList<E> getResults(){ M!e$h?vB
return results; (t\
F>A
} n
7Bua
2}^fhMS
public void setResults(List<E> results){ 1|c\^;cTkt
this.results = results; 6fOh *
} H[a1n' "<:
DfNX@gbo
public String toString(){ LmKG6>Q1#1
StringBuilder buff = new StringBuilder Mk -Rl
#~SQujgB
(); LK'|sO>|
buff.append("{"); pg.z `k
buff.append("count:").append(count); %j3*j
buff.append(",p:").append(p); 8=%%C:
buff.append(",nump:").append(num); DgQw9`WA
buff.append(",results:").append ARD&L$AX
x3JX}yCX
(results); c9
UJ=
buff.append("}"); A$9^JF0$
return buff.toString(); c8'!>#$
} }LaRa.3
z&6TdwhV
} O#e' .n!rI
BWbM$@'x
wlM"Zt