Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 D.(G 9H
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 YJ$ewK4E#.
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 F-^HN%
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 G+uiZ(p>
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分页支持类: 3Mx@
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java代码: SbZt\a 8
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package com.javaeye.common.util; cO,V8#H
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import java.util.List; zXZ'nJ5OGG
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publicclass PaginationSupport { <(4#4=ivP
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publicfinalstaticint PAGESIZE = 30; Eap/7U1Q
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privateint pageSize = PAGESIZE; -vHr1I<
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privateList items; A Vm{#^p[(
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privateint totalCount; U@MP&sdL
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privateint[] indexes = newint[0]; jJ!-hg4?]
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privateint startIndex = 0; ex\W]5
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public PaginationSupport(List items, int *ldMr{s<R
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totalCount){ W@,p9=425
setPageSize(PAGESIZE); -Zg @D(pF
setTotalCount(totalCount); Reu{
setItems(items); *Ca)RgM
setStartIndex(0); 9K':Fn2,
} lt6;*z[
j yRSEk$
public PaginationSupport(List items, int =nx:GT3&[
H'{?aaK|t
totalCount, int startIndex){ [!@oRK=~
setPageSize(PAGESIZE); :z.Y$]F@
setTotalCount(totalCount); *xg`Kwl5Kl
setItems(items); 9xn23*Fo
setStartIndex(startIndex); ceZ8}Sh
} UVc<C
1q
^}Qj}
public PaginationSupport(List items, int N4mJU'_{
s;2/Nc
totalCount, int pageSize, int startIndex){ +'/}[1q1/T
setPageSize(pageSize); *fi;ZUPW3
setTotalCount(totalCount); PCPf*G>
setItems(items); !?o$-+a|
setStartIndex(startIndex); ^YR|WK Y
} X@qk> /
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publicList getItems(){ R
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return items; ggI=I<7M
} s)YP%vn#
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publicvoid setItems(List items){ ^8NLe9~p3?
this.items = items; s!ZW'`4!z
} z8/xGQn
pp]_/46nN
publicint getPageSize(){ <*"pra{3
return pageSize; OR\DTLIl
} pEVgJ/>
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publicvoid setPageSize(int pageSize){ /.)[9bQ<
this.pageSize = pageSize; -~\.n
} .S!>9X,
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publicint getTotalCount(){ 4b2mtLn_
return totalCount; "f|(@a
} pAil]f6
sQ}%7BMK
publicvoid setTotalCount(int totalCount){ E8-fW\!F
if(totalCount > 0){ l]Ui@X
this.totalCount = totalCount; AL]h|)6QpC
int count = totalCount / pSQCT
/*AJr
pageSize; nFe` <Al$N
if(totalCount % pageSize > 0) m0j|58~
count++; 3gG+`{<
indexes = newint[count]; cRh\USS
for(int i = 0; i < count; i++){ *:9 >W$0u
indexes = pageSize * H5Ux.]y
.vN%UNu
i; SgpZ;\_
} >AQ)x
}else{ /z1p/RiX
this.totalCount = 0; `M?v!]o
} C[xJU6z
} 1t~FW-:
Y .
publicint[] getIndexes(){ {b'}:aMc
return indexes; hG3m7ht
} A{z>D`d
sK@Y!oF}\
publicvoid setIndexes(int[] indexes){ #9D/jYK1X
this.indexes = indexes; ZU-4})7uSB
} -J"qrpZ^
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publicint getStartIndex(){ 6[*;M
return startIndex; 4[TS4p
} UU iNR
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publicvoid setStartIndex(int startIndex){ cgs3qI
if(totalCount <= 0) -,QKTxwo>
this.startIndex = 0; e^k!vk-SLF
elseif(startIndex >= totalCount) ;Y'8:ncDn
this.startIndex = indexes 6|
*(dE2x(
d"B@c;dD
[indexes.length - 1]; J}Qs"+x
elseif(startIndex < 0) ]8$#qDS@
this.startIndex = 0; rH$eB/#F
else{ |*^8~u3J"
this.startIndex = indexes uW}Hvj;0a*
URYZV8=B~
[startIndex / pageSize]; =U4f}W;
} &|Lh38s@$#
} K,f* SXM
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publicint getNextIndex(){ *.,"N}
int nextIndex = getStartIndex() + `d7gm;ykp
SU%mmwES3
pageSize; .E+OmJwD
if(nextIndex >= totalCount)
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return getStartIndex(); q&zny2])
else J>`v.8y
return nextIndex; WD15pq l
} iH-bo@
2E$^_YT
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publicint getPreviousIndex(){ Hf VHI1f
int previousIndex = getStartIndex() - w&p~0cA~
_*s~`jn{H
pageSize; P+Wm9xR2d
if(previousIndex < 0) zlH28V
return0; h&lyxYZ+T$
else X<(6T
return previousIndex; 7MY)\aH
} {7vgHutp
[6AHaOhR'
} m_a^RB(
JC=dYP}
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抽象业务类 hZcmP"wgC1
java代码: \B_i$<Sz
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/** NX?}{'f
* Created on 2005-7-12 5XDgs|8
*/ ?TDvCL
package com.javaeye.common.business; mge#YV::
n_v02vFAHT
import java.io.Serializable; C(G(^_6
import java.util.List; i8K_vo2Z)
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import org.hibernate.Criteria; _B)s=Snx
import org.hibernate.HibernateException; 2Kjrw;
import org.hibernate.Session; hjkLVL
import org.hibernate.criterion.DetachedCriteria; ;; :">@5
import org.hibernate.criterion.Projections; |2O')3p"9
import xcst<=
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org.springframework.orm.hibernate3.HibernateCallback; KyT uF
import T/ik/lFI
-$.0Dc)3!
org.springframework.orm.hibernate3.support.HibernateDaoS AcKU^T+
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upport; axX{6
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import com.javaeye.common.util.PaginationSupport; mjbTy"}"
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public abstract class AbstractManager extends IroPx#s:i
@Tm`d ?^
HibernateDaoSupport { }3Qc 24`
@K\o4\
privateboolean cacheQueries = false; bl=ku<}@
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privateString queryCacheRegion; H<g 1m
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publicvoid setCacheQueries(boolean }`9jH:q-Z
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cacheQueries){ >z(wf>2J
this.cacheQueries = cacheQueries; 1w`2Dt
} =~&VdPZ
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publicvoid setQueryCacheRegion(String ;+a2\j+
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#w
queryCacheRegion){ =-w;zx
this.queryCacheRegion = "tUwo(K[
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queryCacheRegion; UbO4%YHt
} 5Tedo~v
vwmBUix
publicvoid save(finalObject entity){ ++b$E&lYU
getHibernateTemplate().save(entity); |#k@U6`SG
} }AlYNEY
PQ$sOK|/
publicvoid persist(finalObject entity){ Nar>FR7ut
getHibernateTemplate().save(entity); nq1
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} 7tRi"\[5
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publicvoid update(finalObject entity){ [KSH~:h:NR
getHibernateTemplate().update(entity); sef]>q
} /N6}*0Ru
X d3}Vn=
publicvoid delete(finalObject entity){ Zyu/|Og
getHibernateTemplate().delete(entity); wPX*%0]
} 8#w)X/
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publicObject load(finalClass entity, &dr@6-xaq
9gy(IRGq/
finalSerializable id){ le8 #Z}p
return getHibernateTemplate().load L0L2Ns
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(entity, id); a7#?h%wf
} eklgLU-+fW
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publicObject get(finalClass entity, vQ1 v#Z
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finalSerializable id){ u#@RM^738d
return getHibernateTemplate().get {e"dm5
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(entity, id); .t=
} ; b*i3*!g
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publicList findAll(finalClass entity){ \vRd}
return getHibernateTemplate().find("from ]A^4}CK^<
Su7bm1
" + entity.getName()); ((bTwx
} V
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publicList findByNamedQuery(finalString T.ML$"f
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namedQuery){ 36vgX=}
return getHibernateTemplate cj$d=k~
nS9wb1Zl
().findByNamedQuery(namedQuery); _MuZ4tc
} ]{GDS! )
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publicList findByNamedQuery(finalString query, @1:0h9%
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finalObject parameter){ !q'
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return getHibernateTemplate V 1/p_)A
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().findByNamedQuery(query, parameter); xr%#dVk
} h&;t.Gdf
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publicList findByNamedQuery(finalString query, S6g<M5^R
}ptq
)p
finalObject[] parameters){ b~w=v_[(I
return getHibernateTemplate t e,[f
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().findByNamedQuery(query, parameters); (V?: ]
} z~{&}Em ~
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publicList find(finalString query){ 69G`2_eKCp
return getHibernateTemplate().find oD.r`]k
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(query); CU)|-*uiK
} 3\:y8|
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publicList find(finalString query, finalObject ,xfO;yd
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parameter){ gckI.[!b
return getHibernateTemplate().find IzLQhDJ1
y[?-@7i
(query, parameter); qfoD
} i+{yMol1
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public PaginationSupport findPageByCriteria hA1-){aw3q
&ldBv_
(final DetachedCriteria detachedCriteria){ 8|%^3O 0X
return findPageByCriteria ,|kDsR!
6#@ f'~s
(detachedCriteria, PaginationSupport.PAGESIZE, 0); om h{0jA0
} 7U|mu~$.!
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public PaginationSupport findPageByCriteria ,yd= e}lQx
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(final DetachedCriteria detachedCriteria, finalint qIMA6u/
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startIndex){ O1'm@
q)
return findPageByCriteria RQB
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@]aOyb@
(detachedCriteria, PaginationSupport.PAGESIZE, "vZ!vt#'Y
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startIndex); TuDE@ gq(
} D B E4&
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public PaginationSupport findPageByCriteria VVP:w%yW
h vka{LD
(final DetachedCriteria detachedCriteria, finalint sarq`%zrk
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pageSize, \</b4iR)LT
finalint startIndex){ -Go 7"j
return(PaginationSupport) r.ZF_^y}+
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getHibernateTemplate().execute(new HibernateCallback(){ qqrq11W
publicObject doInHibernate ma'FRt
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(Session session)throws HibernateException { MY#
Criteria criteria = B=8Iu5m
UFAL1c<V
detachedCriteria.getExecutableCriteria(session); Xce0~\_A
int totalCount = *jIqAhs0{
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((Integer) criteria.setProjection(Projections.rowCount jw<pK4?y
29CINC
()).uniqueResult()).intValue(); /zDi9W*~1
criteria.setProjection }v:jncp
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(null); ?`zXLY9q7
List items = } :=Tm]S
n_ lo`
criteria.setFirstResult(startIndex).setMaxResults &e-U5'(6v_
w@JKl5
(pageSize).list(); 8{`?=&%6
PaginationSupport ps = LI2&&Mw
JM1R ;i6
new PaginationSupport(items, totalCount, pageSize, M])dJ9&e
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startIndex); EnOU?D
return ps; ;bHV
} Vq;dJ%sY
}, true); [(1c<b2r
} ;q N+^;,2
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public List findAllByCriteria(final @2'Mt}R>
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DetachedCriteria detachedCriteria){ !,V{zTR
return(List) getHibernateTemplate -'~LjA(
,|&9M^
().execute(new HibernateCallback(){ p-.n3AL
publicObject doInHibernate P(F+f`T
pPd#N'\*
(Session session)throws HibernateException { V< k8N^
Criteria criteria = o sKKt?^?
|2{wG4
detachedCriteria.getExecutableCriteria(session); "*G.EiLq
return criteria.list(); 8\:NMP8W\
} Kq i4hK
}, true); AU2i%Q!
} u\eEh*<7q
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public int getCountByCriteria(final */|BpakD<
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DetachedCriteria detachedCriteria){ pAT7)Ch
Integer count = (Integer) fbUr`~Y"
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getHibernateTemplate().execute(new HibernateCallback(){ bV,}Pp+/"!
publicObject doInHibernate 9k{PBAP
2RSt)3!},
(Session session)throws HibernateException { -[-wkC8a
Criteria criteria = RjN{%YkXe
..rOsg{
detachedCriteria.getExecutableCriteria(session);
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return n=[/Z!
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criteria.setProjection(Projections.rowCount KEWTBBg
>,td(= :
()).uniqueResult(); jy'13G/b\
} z[Xd%mhjO
}, true); KZ/=IP=
return count.intValue(); K'GBMnjD
} ght$9>'n
} T?X_c"{8M
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用户在web层构造查询条件detachedCriteria,和可选的 uCcYPvm
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 -,U3fts
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PaginationSupport的实例ps。 '*3h!lW1.
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ps.getItems()得到已分页好的结果集 ?nL.w
ps.getIndexes()得到分页索引的数组 x9JD\vZ
ps.getTotalCount()得到总结果数 >D4#y
ps.getStartIndex()当前分页索引 d QqK^#
ps.getNextIndex()下一页索引 ;n
7/O5M|
ps.getPreviousIndex()上一页索引 w4gJoxY-`
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ,'u W*kx
h D/*h*}T>
,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 nR-YrR*k
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一下代码重构了。 cH&J{WeZa
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我把原本我的做法也提供出来供大家讨论吧: w9bbMx
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首先,为了实现分页查询,我封装了一个Page类: S Em Q@1
java代码: |AozR ~
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/*Created on 2005-4-14*/ R21b!Pd\
package org.flyware.util.page; Jt}Bpg!J
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/** j3{D^|0bP
* @author Joa yjF1}SQ
* 7Mg=b%IYs
*/ $adbCY\
publicclass Page { 6V7B;tB
%yv<y+yP~
/** imply if the page has previous page */ ]d!
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privateboolean hasPrePage; qm"rY\:
Q|#W#LV,K
/** imply if the page has next page */ ,Vt/(x-
privateboolean hasNextPage; Y!nJg1
3`t%g[D1
/** the number of every page */ F9,DrB,B{
privateint everyPage; ,Y/ g2
4R
!:q/Ye3.
/** the total page number */ ,X`)ct
privateint totalPage; sTn<#l6
hHV";bk
/** the number of current page */ e,W%uH>X
privateint currentPage; NTYg[VTr
%H]ptH5
/** the begin index of the records by the current ur:3W6ZKl
5\]Sv]s)R
query */ xdp`<POn%
privateint beginIndex; R#%(5-Zu#R
Z{]0jhUyNh
7$CBx/X50)
/** The default constructor */ 5kCUaPu
public Page(){ v|dBSX9k0
6WXRP;!Q
} CxwoBuG=?
`erV$( M
/** construct the page by everyPage /`wvxKX
* @param everyPage PHZ0P7
* */ @~^5l
public Page(int everyPage){ J IUx
this.everyPage = everyPage; JB<Sl4
} ,$s8GAmq
n\*!CXc
/** The whole constructor */ ;$.J3!
public Page(boolean hasPrePage, boolean hasNextPage, Egg=yF>T
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A kC1z73<
int everyPage, int totalPage, %A1o.{H
int currentPage, int beginIndex){ TO]@
Zu1
this.hasPrePage = hasPrePage; ~*z% e*EL
this.hasNextPage = hasNextPage; RtTJ5@V(
this.everyPage = everyPage; ME46V6[LX]
this.totalPage = totalPage; =P't(<
this.currentPage = currentPage; zv0l,-o
this.beginIndex = beginIndex; Yc_8r+;(
} p<2L.\6"
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/** 6dabU*
* @return J8uLJ
* Returns the beginIndex. v+46QK|I&
*/ /:~\5}tW
publicint getBeginIndex(){ tn(JC%?^
return beginIndex; ,)Me
} MQ5R O;RY
T@2#6Tffo
/** m% -g ~q
* @param beginIndex f$e[u
Er
* The beginIndex to set. 7puFz4+f
*/ ObVGV
publicvoid setBeginIndex(int beginIndex){ X[]m _@ v
this.beginIndex = beginIndex; 6Ypc`
} Ql/cN%^j$
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/** ,?8qpEG~#+
* @return ORe(]I`Z
* Returns the currentPage. 7K,-01-:
*/ _x%7@.TB
publicint getCurrentPage(){ y{ibO}s
return currentPage; ^1iSn)&
} [$0p+1
g!@<n1 L
/** q rJ`1
* @param currentPage {XR6>]
* The currentPage to set. x+Ttl4
*/ H?<N.Dq
publicvoid setCurrentPage(int currentPage){ C'\-
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this.currentPage = currentPage; k1w_[w[
} Aw$x;3y
^t` k0<
/** XG{{ 2f
* @return $$|rr G
* Returns the everyPage. {MtpkUN
*/ CR8/Ke
publicint getEveryPage(){ _4"mAPt
return everyPage; {@6=Q 6L
} G`SUxhC k
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/** _ky,;9G]
* @param everyPage 5]KW^sL
* The everyPage to set. |^: cG4e
*/ B~ ]k#Ot)
publicvoid setEveryPage(int everyPage){ Aydm2!l1
this.everyPage = everyPage; )Xk0VDNp$/
} 7C,&*Ax,9
O@u?h9?cf>
/** ]op}y0
* @return 7mI:|G
* Returns the hasNextPage. t[ubn+
*/ QS%%^+E2
publicboolean getHasNextPage(){ nygbt<;?
return hasNextPage; K&vF0*gN3
} R<\F:9
od IV:(
/** d/PiiiFf,
* @param hasNextPage x'+T/zw
* The hasNextPage to set. |jI#"LbF
*/ xf<at ->
publicvoid setHasNextPage(boolean hasNextPage){ mw_~*Nc'9
this.hasNextPage = hasNextPage; 5's87Z;6
} XC4X-j3
9>l*lCA
/** Ov5"
* @return w`4=_J=GO
* Returns the hasPrePage. 7E!IF>`
*/ ^8 z R
publicboolean getHasPrePage(){ rf
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return hasPrePage; o)Iff)m$
} $;1#To
)m`<H>[Eb=
/** R n}l6kbM
* @param hasPrePage
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* The hasPrePage to set. *,e:]!*
*/ ]JCvyz
H
publicvoid setHasPrePage(boolean hasPrePage){ zz+$=(T:M
this.hasPrePage = hasPrePage; KC/=TSSXd.
} (\\eo
r[2ILe
/** }Ga\wV
* @return Returns the totalPage. ?3nR
* CnpV:>V=
*/ *!q1Kr6r
publicint getTotalPage(){ bSiYHRH.e
return totalPage; #r#1JtT
} T=iJGRctB
Id_2PkIN$~
/** r"C
* @param totalPage
#bUXgn>
* The totalPage to set. YM1'L\^
*/ TT2d81I3m
publicvoid setTotalPage(int totalPage){ F20E_2;@@
this.totalPage = totalPage; !Fca~31R'
} M$y+q
^
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} ?ATOXy
W}m)cn3@
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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 KV]X@7`@
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个PageUtil,负责对Page对象进行构造: JW{rA6?
java代码: q)Lu_6 mg
q"%_tS
8cU}I4|
/*Created on 2005-4-14*/ k,85Y$`'
package org.flyware.util.page; GC?ON0g5s
rm5bkJcg~
import org.apache.commons.logging.Log; ~ DBcIy?
import org.apache.commons.logging.LogFactory; \SN&G`o<
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/** s"0Y3x3
* @author Joa !F1M(zFD
* R@/"B8H
*/ o^^rJk
publicclass PageUtil { =8t]\Y?
:# .<[
privatestaticfinal Log logger = LogFactory.getLog ZG>PQA
V,mw[Hw
(PageUtil.class); }j^i}^Du,
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/** Hw7;;HK
7
* Use the origin page to create a new page B
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* @param page Ka[t75~;
* @param totalRecords xC{qV,
* @return uehDIl0\[b
*/ I/&%]"[^u
publicstatic Page createPage(Page page, int E8pB;\Z(
6{"$nF]
totalRecords){ "/3 db[
return createPage(page.getEveryPage(), vK9E
]Bcp;D
page.getCurrentPage(), totalRecords); E;Y;z
} M!/Cknm
]!I7Y.w6
/** $*AYcy7
* the basic page utils not including exception n&"B0y cF
P,xKZ{(
handler +_; l|uhT;
* @param everyPage 8.XoVW#
* @param currentPage X.Rb-@
* @param totalRecords `}(b2Hc>
* @return page Jz7!4mu
*/ e8pG"`wM8
publicstatic Page createPage(int everyPage, int F ~^Jmp7Y
`V`lo,"\
currentPage, int totalRecords){ luo
everyPage = getEveryPage(everyPage); '^No)n\`
currentPage = getCurrentPage(currentPage); O_ChxX0KP
int beginIndex = getBeginIndex(everyPage, QWD'!)Zb
xD5:RE~g
currentPage); j/fzzI0@
int totalPage = getTotalPage(everyPage, f|B=_p80
JBXrFC;
totalRecords); v3aYc:C
boolean hasNextPage = hasNextPage(currentPage, n\xX},
y0#u9t"Z;
totalPage); oXb;w@:
boolean hasPrePage = hasPrePage(currentPage); Fx;QU)1l3
)6q,>whI]
returnnew Page(hasPrePage, hasNextPage, K? y[V1,
everyPage, totalPage, XZsz/#
currentPage, mVVD!
S 5/R_5
beginIndex); D)j(,vt
} sejg&8
)/pU.Z/
privatestaticint getEveryPage(int everyPage){ DVSL [p?_
return everyPage == 0 ? 10 : everyPage; np8gKVD
} Hkwl>R$
*~t6(v?
privatestaticint getCurrentPage(int currentPage){ mS~o?q-n
return currentPage == 0 ? 1 : currentPage; *v9 2
} j6Yy6X]
K
P Oa|$
privatestaticint getBeginIndex(int everyPage, int yf[~Yl>Ogw
-=~| ."O
currentPage){ ~$)2s7
O
return(currentPage - 1) * everyPage; Pb1*\+
} VFRi1\G
"JlpU-8[0@
privatestaticint getTotalPage(int everyPage, int U*22h` S
ujlY!-GM
totalRecords){ _H j!2 '
int totalPage = 0; Xs~[&
;_rF;9z9
if(totalRecords % everyPage == 0) ,1 [q^-9
totalPage = totalRecords / everyPage; '}fzX2Q#
else )n2 re?S
totalPage = totalRecords / everyPage + 1 ; %Z):>'
| # 47O
return totalPage; \QYFAa
} 5*Y^\N
d@5[B0eH
privatestaticboolean hasPrePage(int currentPage){ L<ue$'
return currentPage == 1 ? false : true; 1][4.}?F[
} : cF[(i/k4
xT
privatestaticboolean hasNextPage(int currentPage, ~GL]wF2#
}+C2I
int totalPage){ ,.OERw
return currentPage == totalPage || totalPage == ";3zXk[#
`< xn8h9p
0 ? false : true; 2E}*v5b,
} "#{4d),r
>pp5;h8!
FB{KH .
} ;<j0f~G`
@~YYD#'vNY
]x(e&fyHB
^,/RO5
^/\Of{OZ-
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。 PH+S};Uxv
B{'( L|
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 g^}8:,F_
{<R2UI5m5
做法如下: 8,?h~prc
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 {q`jDDM
+yk24
`>
的信息,和一个结果集List: g*03{l#P
java代码: 6L"%e!be6
Z0Vl+
|mGFts}0o'
/*Created on 2005-6-13*/ $}>+kHoT{
package com.adt.bo; }bdmomV
W-?()dX{
import java.util.List; E5I"%9X0H
ms*(9l.hOK
import org.flyware.util.page.Page; I%sFqh>
U%q7Ai7
/** 0K`#>}W#X
* @author Joa y5?RVlKJ
*/ Ji>o!
publicclass Result { n%-R[vW
W4pL ,(S
private Page page; 9~]~#Uj
mlJ!:WG
private List content; G Uon/G8
"4riSxEyF
/** 4dO~C
* The default constructor ;7?kl>5]
*/ 6{n!Cb[e
public Result(){ /s@o Z{h
super(); VyzS^AHK
} e4H A7=z
ew#B[[
/** 8<8:+M}
* The constructor using fields pTPi@SBaP{
* lI *o@wQg
* @param page = \'}g?
* @param content x:),P-~w
*/ m[~V/N3
public Result(Page page, List content){ Xejo_SV&?
this.page = page; jL%x7?*U0
this.content = content; /&
Jan:
} 8ZM&(Lz7u
6kpg+{;
/** &7PG.Ff!r
* @return Returns the content. Y9uC&/_C
*/ YG@t5j#b
publicList getContent(){ w<Wf?a G
return content; YG3J$_?y0
} 'gC_)rK*
/fZeWU0W
/** jcuB
* @return Returns the page. k5:G-BQ:
*/ 9
Vkb>yFX'
public Page getPage(){ Nl^;A><u
return page; $ M`hh{ -
} M?Dfu
.t
DI:]GED"=
/** QZ6D7tUc8
* @param content pR(jglm7-
* The content to set. NidIVbT.A
*/ B8f8w)m
public void setContent(List content){ `|{-+m
this.content = content; oW ::hB
} s5CXwM6cx
C-Q28lD}f
/** fI&t]
* @param page z\K"Rg~J
* The page to set. @ ;*Ksy@1O
*/ ,?>s>bHV
publicvoid setPage(Page page){ ~Sj9GxTe
this.page = page; * @ 3Ag(
} j[`j9mM8
} (;T^8mI2
qTdh eX/
a1EOJ^}0
B2>H_dmQ
#|L8tuWW
2. 编写业务逻辑接口,并实现它(UserManager, 0?s|i :
RRmz"j>
UserManagerImpl) (}Z@R#njH
java代码: \k .{-nh
8aK)#tNWN
t^+ik1.
/*Created on 2005-7-15*/ NjVYLn<.r
package com.adt.service; aI P
)
i;1*jK
import net.sf.hibernate.HibernateException; f(/lLgI(
Cn,d?H
import org.flyware.util.page.Page; g;pcZ9o
s'!Cp=xQF"
import com.adt.bo.Result; d' !]ZWe
RIlwdt
/** ]~9tYn
* @author Joa ZGexdc%
*/ wxKX{Bs
publicinterface UserManager { 8EW_V$>R
f.D?sH An
public Result listUser(Page page)throws MqW7cjg
dq(uVW^&ae
HibernateException; azCf
\y97W&AN
} gH12[Us'`
/sx@$cvW
JZ)RGSG i
,]|#[ 8
j'Gt&\4
java代码: PQy4{0 _
-.1y(k^4E
T-.%
/*Created on 2005-7-15*/ Bal$+S
package com.adt.service.impl; GzhYY"iif#
kjIAep0rT
import java.util.List; ^yW L,$
r(:5kC8K
import net.sf.hibernate.HibernateException; wo4;n9@I
h{%nC>m;
import org.flyware.util.page.Page; 3x`|
import org.flyware.util.page.PageUtil; "un]Gc
umjt]Gu[
import com.adt.bo.Result; V3&RJ k=b
import com.adt.dao.UserDAO; ]] !VK
import com.adt.exception.ObjectNotFoundException; ). <-X^@
import com.adt.service.UserManager; qraSRK5
WffQ :L?
/** &-;4.op
* @author Joa zNs55e.rx
*/ yMG1XEhuG
publicclass UserManagerImpl implements UserManager { (ceNO4"cZ
X3{G:H0\p
private UserDAO userDAO; yQU{zY
.CL[_;}
/** =O&%c%~q
* @param userDAO The userDAO to set. \K5DOM "#
*/ R cAwrsd
publicvoid setUserDAO(UserDAO userDAO){ h?AS{`.1
this.userDAO = userDAO; DVG(Vw
} N:S/SZI
|z9*GY6RU
/* (non-Javadoc) ZGBd%RWjG_
* @see com.adt.service.UserManager#listUser E%yNa]\P
%aHB"vi6
(org.flyware.util.page.Page) Bc(Y(X$PK
*/ 0]'7_vDs|
public Result listUser(Page page)throws ),0g~'I~D
p)jk>j B
HibernateException, ObjectNotFoundException { :y+2*lV
int totalRecords = userDAO.getUserCount(); G/k2Pe{SL
if(totalRecords == 0) uW=k K0E
throw new ObjectNotFoundException P0SQr?W
\MA+f~)9
("userNotExist"); ^UciW
page = PageUtil.createPage(page, totalRecords); gT3_RUF
List users = userDAO.getUserByPage(page); };mA^xO]j
returnnew Result(page, users); p#&h=,W}
} )mg:_K
6hw=
} |ax3sAg
sGi"rg#
S
^"y4-2
\RNNg
YpWPz %`:
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 {ME2ImD
oL!EYbFD'Z
询,接下来编写UserDAO的代码: rxe>}ZO
3. UserDAO 和 UserDAOImpl: ,-$LmECg
java代码: ,g%0`SO
D60aH!ft
cm&nd'A't
/*Created on 2005-7-15*/ x/NfZ5e0X
package com.adt.dao; O(#)m>A
&T+atL `N
import java.util.List; %D UH@j
F5LuSy+v
import org.flyware.util.page.Page; l>2E (Y|
$~~Jw]
import net.sf.hibernate.HibernateException; p2Z?T}fa}&
"An,Q82oHf
/** }QN1|mP2
* @author Joa JUsQ,ETn
*/ >NO[UX%yP
publicinterface UserDAO extends BaseDAO { D|lzGt
spGb!Y`mR
publicList getUserByName(String name)throws 5 f@)z"j
?L5zC+c!
HibernateException; ?274uAO'
]jtK I4
publicint getUserCount()throws HibernateException; J}*,HT *
qaqBOHI6G
publicList getUserByPage(Page page)throws ]S&&|Fc
'OE&/
C[
HibernateException; =qoWCmg"&
ls?~+\Jb
} 3oBtP<yG.
$'0u |Xy`
:I"2V
I.WvLLK2
XQrF4l
java代码: vV'EZ?
ob+b<HFv
aB*Bz]5;E
/*Created on 2005-7-15*/ 5<iV2Hx
package com.adt.dao.impl; )mI 05
[8.c8-lZ^
import java.util.List; fsmN)_T
XpIklL7
import org.flyware.util.page.Page; Km%]1X7T6
IrR7"`.i
import net.sf.hibernate.HibernateException; V8e>l[tH
import net.sf.hibernate.Query; P]<4R:yb
<m!h&_eg
import com.adt.dao.UserDAO; tf=6\p
!!qK=V|>
/** y>R=`A1b
* @author Joa 4qN{n#{+]
*/ Rh3eLt~|(
public class UserDAOImpl extends BaseDAOHibernateImpl 00<cYy
HpR]q05d
implements UserDAO { d4m=0G`
.0p0_f=
/* (non-Javadoc) _ftI*ni:<
* @see com.adt.dao.UserDAO#getUserByName R]Vt Y7}i,
G
!<Z.]
(java.lang.String) ~Xw"}S5
*/ !ds"9w
publicList getUserByName(String name)throws 5(Cl1Yse=r
JHW"-b
HibernateException { D_?K"E=fw
String querySentence = "FROM user in class MV!{j;g1<
+cWLjPD/}
com.adt.po.User WHERE user.name=:name"; &w 4?)#
Query query = getSession().createQuery `0rd26Qro
}Dp*}=?E
(querySentence); SIe="YG]<
query.setParameter("name", name); |$+3a
return query.list(); ZkgV_<M|
} G=)i{oC
+QB"8-
/* (non-Javadoc) IWBX'|}K
* @see com.adt.dao.UserDAO#getUserCount() > pgX^
*/ Q.bXM?V)
publicint getUserCount()throws HibernateException { A_n7w
int count = 0; pEw"8U
String querySentence = "SELECT count(*) FROM m9)p-1y@5
6f;fx}y
user in class com.adt.po.User"; 3yANv?$a
Query query = getSession().createQuery -1Jg?cPzk
+O'3|M
(querySentence); {Z{75}
count = ((Integer)query.iterate().next TH)"wNa
hrmut*<|
()).intValue(); yhlFFbU
return count; Pnw]Tm}g
} zh4#A
<e
1pQn8[sc@
/* (non-Javadoc) RFKtr
* @see com.adt.dao.UserDAO#getUserByPage YW-usvl&
m%rd0=}57
(org.flyware.util.page.Page) \:R%4w#Jv
*/ $v,dz_O*\
publicList getUserByPage(Page page)throws yH7F''O7
8][nmjk0
HibernateException { X$%'
String querySentence = "FROM user in class XV!6dh!
}{M#EP8q+
com.adt.po.User"; -HQQw$
Query query = getSession().createQuery z,|r*\dw
bAsYv*t%r
(querySentence); :s=NUw_^
query.setFirstResult(page.getBeginIndex()) VzBqjE_
.setMaxResults(page.getEveryPage()); ,l%CX.9
return query.list(); c _\YBe]wJ
} ;V@WtZv
7}1~%:6
} ;sfb 4x4
Ok{*fa.PK
$J4 *U
(
Wa
DvME1]7)
至此,一个完整的分页程序完成。前台的只需要调用 ~0?mBy!-O
Q)"C&)`l
userManager.listUser(page)即可得到一个Page对象和结果集对象 0YaA `
k $M]3}$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 h
a|C&G
n-5W*zk1
webwork,甚至可以直接在配置文件中指定。 'AzDP;6qFI
h1:aKm!
下面给出一个webwork调用示例: KN$}tCU
java代码: `/_o!(Z`
)S`jFQ1
ktI/3Mb@
/*Created on 2005-6-17*/ n 9\
C2r
package com.adt.action.user; tc_286'x
j0Bu-sO$w
import java.util.List; pa#d L!J
yPM3a7-Bm
import org.apache.commons.logging.Log; L93l0eEt
import org.apache.commons.logging.LogFactory; A01AlK_B
import org.flyware.util.page.Page; I[b}4M6E
1[kMOp
import com.adt.bo.Result; nYWvTvZ
import com.adt.service.UserService; Z -,J)gW
import com.opensymphony.xwork.Action; @vpf[j
HfcL%b%G8
/** _C.BFE_p
* @author Joa Fd?"-
*/ +$X#q8j06
publicclass ListUser implementsAction{ A3vUPWdDk
1<+2kBuY
privatestaticfinal Log logger = LogFactory.getLog kR]!Vr*yh
)=\#UE+W
(ListUser.class); ktnuNsp
XIvn_&d;G
private UserService userService; jxiC
Kx,G
;?W|#*=R
private Page page; D*Ik7Pe
?aC'.jH+
privateList users; Sa\!*e_sN
f?oa"
/* tS|9fBdCs
* (non-Javadoc) :
m)
* KQcs3F@t
* @see com.opensymphony.xwork.Action#execute() DvPlV q~
*/ H(2!1?N+
publicString execute()throwsException{ GFfq+=se
Result result = userService.listUser(page); #BJG9DFP4`
page = result.getPage(); !icT/5
users = result.getContent(); iZPCNS"
return SUCCESS; 0OT\"O~S[
} ~ns7O
HQ|MhM/"
/** klQC2drS
* @return Returns the page. +zu(
*/ m~@;~7I x
public Page getPage(){ ?s\
OUr
return page; OS4q5;1#
} #
S}Z8
7a#4tqM#
/** hdnTXs@z
* @return Returns the users. "8~:[G#
*/ N+LL@[
publicList getUsers(){ _2k]3z?
return users; 1^_U;O:I
} I/M _p^
4
SHU
/** jx.[#6e
* @param page LVc4CE
f
* The page to set. O:TlIJwW
*/ Q?8R[i
publicvoid setPage(Page page){ CqHK %M
this.page = page; ^Y u6w\QM
} nt;haeJ
@mE)|.f
/** af#pR&4}
* @param users ixW@7m
* The users to set. t|9 GS|
*/ |u0(t,T
publicvoid setUsers(List users){ AtU v71D:
this.users = users; CNQC^d\ h
} TT50(_8
XW -2~?$
/** .,7JAkB%t
* @param userService zUkN 0
* The userService to set. YoN*:jB<M
*/ T<JwD[(
publicvoid setUserService(UserService userService){ ?+g`HTY u
this.userService = userService; Dq36p${\W
} P&j(,7
} )+6v
e{X6i^%
m_
c1$ngH0
u5 {JQO
>H(i^z/c
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, nB%;S
D?C)BcN
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 aO@7O*
tp6M=MC%
么只需要: eh4gQ^l
java代码: J8M$k/"X
Zm"{V iv]
ndjx|s)E
<?xml version="1.0"?> 5Xl/L
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 'fcMuBc+4
T[,/5J
1.0//EN" "http://www.opensymphony.com/xwork/xwork- FP0G]=ME
HDda@Jy
1.0.dtd"> {fha`i
p8kr/uMP ;
<xwork> UA4J>1 i
B3H|+
<package name="user" extends="webwork- ?lbH02P{v
vKq^D(&cl
interceptors"> |o2sbLp
!).}u,*'no
<!-- The default interceptor stack name (RUT{)p[
] GHt"
--> [/ !;_b\X
<default-interceptor-ref 1G0fp:\w
7]x3!AlV
name="myDefaultWebStack"/> %]gn?`O
Rw6;Z
<action name="listUser" s:2|c]wQ#R
~6pr0uyO`
class="com.adt.action.user.ListUser"> UK$ms~H
<param lqowG!3H
6*qL[m.F[o
name="page.everyPage">10</param> wO:Sg=,
<result
U3izvM
26dUA~|KJ
name="success">/user/user_list.jsp</result> S@}1t4Ls:
</action> \S*$UE]uG
,bM-I2BR
</package> |\dZ'
kaxvPv1
</xwork> !IC-)C,q
bae\Zk%`^
&-czStQ
[U@*1
WYIQE$SEv
/erN;Oo%<
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 Dy]I8_
T;diNfgg
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。 s-Aw<Q)d
OdQT2PA_
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 Qd_Y\PzS
hY*0aZ|(
&n[~!%(
PN$X N<
osOVg0Gyj
我写的一个用于分页的类,用了泛型了,hoho =\,uy8HX
zP:cE
java代码: T1`|~Z?g-
Q|,B*b
K*IxUz(
package com.intokr.util; l
akp
#Ei,(xiP
import java.util.List; &f>eQS=(
l{:a1^[>y
/** j7MO'RX`&
* 用于分页的类<br> Xt{*N-v\
* 可以用于传递查询的结果也可以用于传送查询的参数<br> -UZ@G~K
* F,GN[f-
* @version 0.01 4D$;KokZ
* @author cheng lJzl6&
*/ tM,%^){p$
public class Paginator<E> { Q\Gq|e*
privateint count = 0; // 总记录数 x$wd
O
privateint p = 1; // 页编号 [xfaj'j=@
privateint num = 20; // 每页的记录数 v[TYc:L=
privateList<E> results = null; // 结果 ~1*A
!mRx$
%ul
/** q8Nn%o=5V
* 结果总数 nx:KoB"ny
*/ `e]6#iJ^
publicint getCount(){ .6m "'m0;
return count; aup6?'G;
} tu>{
[EY`am8[
publicvoid setCount(int count){ nRb^<cZf
this.count = count; c=[q(|+O!
} a`E*\O'd
_Cy:]2o
/** #5&jt@NS
* 本结果所在的页码,从1开始 .fzu"XAPu
* kvGCbRC
* @return Returns the pageNo. 'r} zY-FM`
*/ <w>/^|]#
publicint getP(){ ?Pwx~[<1""
return p; D-IR!js ]
} ~:lKS;PRuK
:%JC^dV(
/** T#!lPH :&h
* if(p<=0) p=1 _Mc>W0'5@
* "BVdPS DBk
* @param p lFUWV)J\
*/ h(B,d,q"
publicvoid setP(int p){ NQ|xM"MqD
if(p <= 0) z[#Fog
p = 1; +'#oz+
this.p = p; b[@VYa
} |<`.fOxJP
}wwe}E-e
/** \aP6_g:N}
* 每页记录数量 JR9$.fGJ
*/ (QB+%2v
publicint getNum(){ `@`1pOb
return num; RGD]8mw
} 64j|}wJ$
hzY[
G:
/** | A:@&|
* if(num<1) num=1 Y'`"9Db
*/ .wK1El{bf
publicvoid setNum(int num){ !&]z*t
if(num < 1) oc{EuW{Ag
num = 1; p"`%
this.num = num; m@rSz
} w7-WUvxl
%*z-PT22
/** DB`QsiC)
* 获得总页数 GZ}/leR
*/ %G?K@5?j?
publicint getPageNum(){ {SG>'KXZ
return(count - 1) / num + 1; F6S~$<
} ~ eN8|SR
nhdTTap&9
/** z,*:x4}F
* 获得本页的开始编号,为 (p-1)*num+1 (A/0@f1#
*/ beZ(o?uK
publicint getStart(){ }Ia 0"J4
return(p - 1) * num + 1; zPZF|%|
} PI|`vC|yy&
%85Icg
/** Jm(ixekp
* @return Returns the results.
FfM nul
*/ ~U}Mv{y
publicList<E> getResults(){ ]UNZd/hIL
return results; o;`!kIQ
} QLbMPS
@qK<T
public void setResults(List<E> results){ ilEi")b=
this.results = results; b; 9n'UX\
} }uX|5&=~f
kI*Uk M-
public String toString(){ eZF'Ck y
StringBuilder buff = new StringBuilder -!*p*3|03|
Q
e1oT)
(); #Ws53mT
buff.append("{"); 6E9N(kFYs
buff.append("count:").append(count); ,EhVSrh)_4
buff.append(",p:").append(p); X<MpN5%|Wo
buff.append(",nump:").append(num); 6Dm+'y]l
buff.append(",results:").append :%_q[}e
HdQj?f3
(results); Li`hdrO'ii
buff.append("}"); ]TK=>;&
return buff.toString(); a&/HSf_G
} t&c&KFK)I&
pZ+j[!
} vC9@,[
Q5E:|)G
<jd/t19DB