Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ]5hGSl2
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Vv5#{+eT;
]QK@zb}x
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 #e(P~'A0
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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 `DcZpd.n
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。 $XO#qOW
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分页支持类: c!}f\ ]D
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java代码: 7s-ZRb[)1
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package com.javaeye.common.util; 4'ymPPY
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import java.util.List; YQk<1./}I
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/
publicclass PaginationSupport { 3gzcpFNqX
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W)R
publicfinalstaticint PAGESIZE = 30; 6su^yt
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privateint pageSize = PAGESIZE; *K1GX
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privateList items; NiTLQ"~e
9e:}qO5)
privateint totalCount; a;$'A[hq
sTALOL<
privateint[] indexes = newint[0]; Yh}F
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privateint startIndex = 0; |p1pa4%}
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public PaginationSupport(List items, int ,wvzY7%
8+7=yN(
totalCount){ ve|`I=?2
setPageSize(PAGESIZE); H _%yh,L
setTotalCount(totalCount); VD*xhuy$k
setItems(items); M!ra3Y
setStartIndex(0); ix=H=U]Q{
} (YJ]}J^
ORo +=2
public PaginationSupport(List items, int 5wws8w
;f8$vW];
totalCount, int startIndex){
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setPageSize(PAGESIZE); ^Q\O8f[u
setTotalCount(totalCount); "?~u*5
setItems(items); :RnFRAcr
setStartIndex(startIndex); *8*E\nZx!
} !hJ%
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public PaginationSupport(List items, int (y xrK
]k(n_+!
totalCount, int pageSize, int startIndex){ )!!xvyc
setPageSize(pageSize); L8FLHT+R-
setTotalCount(totalCount); Ih!D6
setItems(items); "c S?t
setStartIndex(startIndex); %7$oig\wE
} S}rW=hO
-Oro$=%
publicList getItems(){ LK^t](F
return items; !%x=o&
} Z~-A*{u?
\y%:[g}Fvw
publicvoid setItems(List items){ @YEdN}es
this.items = items; J6H3X;vxQw
} I&e,R
Q7]VB p4
publicint getPageSize(){ +=y ktf
return pageSize; 1z\>>N$7B
} T F !Lp:
U 6y
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publicvoid setPageSize(int pageSize){ U-$ B"w &
this.pageSize = pageSize; N2"4dVV;
} []{g9CO
#]yb;L
publicint getTotalCount(){ #<7ajmr
return totalCount; %`c?cB
} ( /cW
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publicvoid setTotalCount(int totalCount){ ^%v<I"<Uq5
if(totalCount > 0){ xpf\S10e
this.totalCount = totalCount; qR~s&SC#
int count = totalCount / TT429
&S.zc@rN
pageSize; hwmpiyu
if(totalCount % pageSize > 0) ?^F#}>C
count++; HHbkR2H1
indexes = newint[count]; _BcYS
for(int i = 0; i < count; i++){ x0])&':!
indexes = pageSize * S?}@2[
[`^x;*C
i; &8Cuu$T9)
} :B=p%C
}else{ ;a+>><x]
this.totalCount = 0; `A\
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} _|MY/SN4A
} z,nRw/o
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publicint[] getIndexes(){ `@{qnCNQ
return indexes; H~c+L'=
} FU0&EO
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publicvoid setIndexes(int[] indexes){ .E_`*[ 5=
this.indexes = indexes; g eaeOERc
} :~ 3/
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publicint getStartIndex(){ ,vQkvuz
return startIndex; uU`zbh}]L.
} +fzZ\
}k}5\%#li5
publicvoid setStartIndex(int startIndex){ Dyp'a
if(totalCount <= 0) FuaGr0]
this.startIndex = 0; M`umfw T
elseif(startIndex >= totalCount) /Mf45U<
this.startIndex = indexes U %Aj~K^b
G%anot
[indexes.length - 1]; L[+65ce%*
elseif(startIndex < 0) bTKzwNx
this.startIndex = 0; l\5qa_{z
else{ m%q#x8Fp
this.startIndex = indexes a2iaP
NF0} eom
[startIndex / pageSize]; PG)dIec
} b n^^|i
} 33couAP#
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publicint getNextIndex(){ yA(H=L-=!1
int nextIndex = getStartIndex() + Jx_ OT C
av
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pageSize; Q=~e|
if(nextIndex >= totalCount) +S|y)W8
return getStartIndex(); W;IvR
else _}`iLA!$I
return nextIndex; L<QqQ"`
} [ OMcSd|nf
Aye!@RjM8
publicint getPreviousIndex(){ Wuye:b!
int previousIndex = getStartIndex() - IcPIOCmOc
rtf>\j+
pageSize; ykl./uY'
if(previousIndex < 0) tTF/$`Q#*
return0; ctdV4%^{
else ^b;.zhp8;N
return previousIndex; v"_hWJ)
} |/ZpZ7
b)$<aFl
} `6lc] r
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2}I1z_dq~
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抽象业务类 / $WEO[o
java代码: Q?7UiTZ
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/** tQz-tQg
* Created on 2005-7-12 -`iZBC50
*/ sqJ?dIBH
package com.javaeye.common.business; TS$ 2K
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import java.io.Serializable; v~ZdMQvwt
import java.util.List; 5cgDHs
h&[]B*BLr
import org.hibernate.Criteria; hM/|k0YV
import org.hibernate.HibernateException; 8>6+]]O
import org.hibernate.Session; ^C_Y[i
~|
import org.hibernate.criterion.DetachedCriteria; /V2^/`&;a
import org.hibernate.criterion.Projections; /u*((AJ?Qv
import ^l7u^j
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org.springframework.orm.hibernate3.HibernateCallback; C{-e(G`Yd
import
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org.springframework.orm.hibernate3.support.HibernateDaoS V
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_rY,=h{+
upport; \;.\g6zX
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import com.javaeye.common.util.PaginationSupport; R4]t D|
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public abstract class AbstractManager extends sZFjkfak
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HibernateDaoSupport { U<KvKg
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privateboolean cacheQueries = false; +I;b,p
*y='0)[BD
privateString queryCacheRegion; /3L1Un*
0.~QA+BD:S
publicvoid setCacheQueries(boolean 506B=
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cacheQueries){ imZi7o
this.cacheQueries = cacheQueries; cuB~A8H#}
} V ;
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publicvoid setQueryCacheRegion(String SirjWYap
p'0jdb :S
queryCacheRegion){ | -e*^|
this.queryCacheRegion = 2+s_*zM-
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queryCacheRegion; 'u@
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} (Ub=sC
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publicvoid save(finalObject entity){ -}/u?3^-
getHibernateTemplate().save(entity); >8"oO[U5>
} *!$4
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publicvoid persist(finalObject entity){ &na#ES$X,
getHibernateTemplate().save(entity); wc*5s7_
} -icOg6%
Hzcy'
publicvoid update(finalObject entity){ puF'w:I(
getHibernateTemplate().update(entity); <Bn^+u \
} n#uH^@#0
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publicvoid delete(finalObject entity){ =Mzg={)v
getHibernateTemplate().delete(entity); #=V%S
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} r Lg(J|^
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publicObject load(finalClass entity, jL(=<R(~y
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finalSerializable id){ w<3}(1
return getHibernateTemplate().load kTb.I;S
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(entity, id); ZF"f.aV8)
} !rZO~a0
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publicObject get(finalClass entity, rlT[tOVAY
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finalSerializable id){ \(Dq=UzQI
return getHibernateTemplate().get ^m;dEe&@F
.;yy=
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(entity, id); k_/hgO
} T)&J}^j
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publicList findAll(finalClass entity){ !sQ$a#Ea
return getHibernateTemplate().find("from I<e[/#5P\`
bN$`&fC0
" + entity.getName()); )f-u x5
} hLPg=8nJ_
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publicList findByNamedQuery(finalString <h^'x7PkW5
*Dtwr
namedQuery){ xT70Rp(2po
return getHibernateTemplate j}uFp|df<
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().findByNamedQuery(namedQuery); F@Y)yi?z
} 0@d )DLM?
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publicList findByNamedQuery(finalString query, Rn~FCj,-
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finalObject parameter){ #u~s,F$De
return getHibernateTemplate OLJb8kO
u
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().findByNamedQuery(query, parameter); mt3j- Mw
} Ni*f1[sI<
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publicList findByNamedQuery(finalString query, pA%XqG*=Y
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finalObject[] parameters){ 1{4d)z UB
return getHibernateTemplate hO(8v&ns3
kF.!U/C
().findByNamedQuery(query, parameters); ]vJZ v"ACn
} 4)BZ%1+
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publicList find(finalString query){ 3#huC=zbf
return getHibernateTemplate().find {MdxIp[
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(query); A!Zjcp|
} _=E))Kp{z
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publicList find(finalString query, finalObject @*q WV*$h
}uo5rB5D
parameter){ s<gZB:~
return getHibernateTemplate().find ~t[ #p:
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(query, parameter); vpXC5|9U
} B!GpD@U
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public PaginationSupport findPageByCriteria Mf7Q+_!
;Q&38qI
(final DetachedCriteria detachedCriteria){ <GPL8D
return findPageByCriteria ~R/w~Kc!/A
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); r|4jR6%<'m
} BM=`zGh"
t^ LXGQ
public PaginationSupport findPageByCriteria _ _cJ+%e
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(final DetachedCriteria detachedCriteria, finalint ?g|K"P<1
v{`Z
startIndex){ WsRG>w3"
return findPageByCriteria /_y%b.f^
44FK%TmtF
(detachedCriteria, PaginationSupport.PAGESIZE, "6_#APoP
@Tb
T
startIndex); 9|WBJ6
} _'<V<OjVM!
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public PaginationSupport findPageByCriteria #Z<pks2
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(final DetachedCriteria detachedCriteria, finalint wGa0w*$
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pageSize, 4NN-'Z>a
finalint startIndex){ 3lH#+@
return(PaginationSupport) Je_Hj9#M\d
ov: h4
getHibernateTemplate().execute(new HibernateCallback(){ /*p4(D_A
publicObject doInHibernate d,[.=Jqv[
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(Session session)throws HibernateException { uW%7X2K
Criteria criteria = ^@l_K +T
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detachedCriteria.getExecutableCriteria(session); ~ z4T
int totalCount = v:1l2Y)g
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((Integer) criteria.setProjection(Projections.rowCount ZiM#g1;
$_ub.g|
()).uniqueResult()).intValue(); BF8n: }9U
criteria.setProjection @_^QBw0
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(null); :,rD5aOQ
List items = Fn$/ K
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criteria.setFirstResult(startIndex).setMaxResults vLR)B@O,2
r5Ej
(pageSize).list(); +*,rOK`C
PaginationSupport ps = >C"cv^%c
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new PaginationSupport(items, totalCount, pageSize, 9(lIz{
lz\{ X
startIndex); !jY/}M~F1
return ps; +4\JY"oi
} *LcLYxWo
}, true); vM~/|)^0sW
} i0/gyK
s([9/ED
public List findAllByCriteria(final
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DetachedCriteria detachedCriteria){ +A8S 6bA[=
return(List) getHibernateTemplate Le9r7O:
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().execute(new HibernateCallback(){ z
publicObject doInHibernate _/ j44q
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(Session session)throws HibernateException { //@_`.
Criteria criteria = \<|a>{`7]i
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detachedCriteria.getExecutableCriteria(session); }#zE`IT
return criteria.list(); nQK@Uy5Yr
} ;hF >iw
}, true); B)
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} R<LW*8
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public int getCountByCriteria(final :i0xer
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DetachedCriteria detachedCriteria){ G+4a%?JH
Integer count = (Integer) 0K>rc1dy
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getHibernateTemplate().execute(new HibernateCallback(){ 7}Z.g9<
publicObject doInHibernate QI~s~j
\sHM[nF0
(Session session)throws HibernateException { g _;5"
Criteria criteria = W6'+#Fp
pW8pp?
detachedCriteria.getExecutableCriteria(session); 9UOx~Ty
return 1jo.d
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criteria.setProjection(Projections.rowCount w$A*|^w1
TCU|k ,
()).uniqueResult(); z%ljEI"<C
} kr8NKZ/
}, true); (~-q}_G;Q
return count.intValue(); hw_7N)}
} ./kmI#gaV
} QC~B8 ]
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用户在web层构造查询条件detachedCriteria,和可选的 uI%h$
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ;Iw'TF
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PaginationSupport的实例ps。 R- `{W:S
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ps.getItems()得到已分页好的结果集 Y8.0R-:ZAN
ps.getIndexes()得到分页索引的数组 ~FZLA}
ps.getTotalCount()得到总结果数 fouy??
ps.getStartIndex()当前分页索引 '7>Vmr6
ps.getNextIndex()下一页索引 QC4_\V>[
ps.getPreviousIndex()上一页索引 tt|U,o
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 a6WE,4T9
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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 Aplqxvth
RfN5X}&A
一下代码重构了。 'ZT!a]4
d q:M!F
我把原本我的做法也提供出来供大家讨论吧: NXeo&+F
V$q%=Sip
首先,为了实现分页查询,我封装了一个Page类: U{>!`RN
java代码: m{%_5 nW
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/*Created on 2005-4-14*/ ,)]ZD H
package org.flyware.util.page; \`>Y
t T-]Vj.
/** "j$}'uK<
* @author Joa [FiXsYb.8
* q6j]j~JxB
*/ /unOZVr(
publicclass Page { Q2rZMK
m
7 Fz&bN
/** imply if the page has previous page */ )QBsyN<x6
privateboolean hasPrePage; *tRJ=
"45BOw&72G
/** imply if the page has next page */ Tj:+:B(HB
privateboolean hasNextPage; 9\Xl3j!
3M1(an\nW
/** the number of every page */ e1<28g
privateint everyPage; "a,Tc2xk
@Zq,mPaR$
/** the total page number */ _LK>3Sqd
privateint totalPage; S^x9 2&!
y]?$zbB
/** the number of current page */ "g=ux^+X\
privateint currentPage; g LpWfT29V
w_U5w
/** the begin index of the records by the current tD4IwX
@~63%6r#4M
query */
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privateint beginIndex; U4N
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`M7){
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/** The default constructor */ r<|\4zIo/
public Page(){ >F-J}P
._FgQ``PL
} v(: VUo]H
Zfb:>J@h6
/** construct the page by everyPage n]j(tP
* @param everyPage #=O0-si]P
* */ B;K{Vo:C
public Page(int everyPage){ !)\`U/.W
this.everyPage = everyPage; xE6y9"}!h
} s?`)[K'-
erqm=)
/** The whole constructor */ P$pl
public Page(boolean hasPrePage, boolean hasNextPage, P?0b-Qr$a
)bK<t
6]rrj
int everyPage, int totalPage, zP9 HYS
int currentPage, int beginIndex){ hM8G"b
this.hasPrePage = hasPrePage; qQ1m5_OD`z
this.hasNextPage = hasNextPage; G3U+BC23E
this.everyPage = everyPage; -y/?w*Cx
this.totalPage = totalPage; [j!0R'T
this.currentPage = currentPage; fptW#_V2
this.beginIndex = beginIndex; iww h,(
} S[u<vHy
)>[(HxvfJU
/** d>AVUf<o~
* @return 8\a)}k~4
* Returns the beginIndex. a"&Z!A:Z=
*/ sztnRX_
publicint getBeginIndex(){ Mys;Il"
return beginIndex; L>L4%?
} F2:7UNy,
"QlCcH`g
/** _nRshTt`V&
* @param beginIndex C#r`oZS1
* The beginIndex to set. J]~fv9~P
*/ C$(t`G
publicvoid setBeginIndex(int beginIndex){ 6*LU+U=`
this.beginIndex = beginIndex; qq?>ulu*W
} }40/GWp<f
n!N;WL3k
/** A>4k4*aFm#
* @return l y%**iN
* Returns the currentPage. .K7A!;
*/ cX=` Tl
publicint getCurrentPage(){ C>03P.s4c
return currentPage; Vm.u3KE
} 22*t%{(
I|LS_m
/** z$<6;2
* @param currentPage {?jdPh
* The currentPage to set. z%AIv%
*/ J%A`M\
publicvoid setCurrentPage(int currentPage){ \hq8/6=4s
this.currentPage = currentPage; sZbzY^P
} O%)9tFT
MkYem6
/** z44uhR h
* @return 21WqLgT3 4
* Returns the everyPage. z`Q5J9_<cV
*/ $}F]pa[
publicint getEveryPage(){ b1&{%.3[
return everyPage; KYl^{F
} P"]+6sm&es
EjF}yuq[
/** hZ#tB
* @param everyPage ,Utw!]
* The everyPage to set. SP*5 W)6
*/ ,AD| u_pP
publicvoid setEveryPage(int everyPage){ JZtFt=>q
this.everyPage = everyPage; HaC3y[ LJ0
} B`WfJ2*2
=L=#PJAPj
/** '^J/aV
* @return o|}%pc3
* Returns the hasNextPage. ~d%Q1F*,=
*/ m3XH3FgKz
publicboolean getHasNextPage(){ (Q4_3<G+
return hasNextPage; y-@!, @e
} g 764wl
HcVPJuD
/** I{AU,
* @param hasNextPage "TV.$s$.
* The hasNextPage to set. C>u 3n^
*/ >4VU
publicvoid setHasNextPage(boolean hasNextPage){ !'gz&3B~h
this.hasNextPage = hasNextPage; bOFLI#p&
} 0iE).Za0g
eHJ7L8#
/** b{ozt\: M
* @return ."^dJ |fN
* Returns the hasPrePage. 2%<jYm#'z-
*/ }?~uAU-
publicboolean getHasPrePage(){ O}`01A!u;
return hasPrePage; :aqh8bv
} \|pAn
ZB2'm3'bh
/** 3D.S[^s*
* @param hasPrePage [!q&r(-K
* The hasPrePage to set. ]EcZ|c7o9y
*/ 0>;#vEF*1
publicvoid setHasPrePage(boolean hasPrePage){ {x4[Bx1
this.hasPrePage = hasPrePage; FezW/+D
} UbibGa=
)
9j2I6lGQ
/** |)4$\<d
* @return Returns the totalPage. w@ 5/mf?
* Hb+#*42v
*/ ]dK]a:S
publicint getTotalPage(){ rO`g~>-
return totalPage; *0hiPj:
} )f!dG(\
'=~y'nPG7
/** Z+dR(9otH3
* @param totalPage 5muW*7
* The totalPage to set. Gh|!FRK[$
*/ X@:fW @
publicvoid setTotalPage(int totalPage){ /T(\}Z
this.totalPage = totalPage;
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} 4@V]zfu^Q
5p|@ )
} j>Z]J'P
{^kG<v.vV
|Hm'.-
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,?`1ve_K<
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 IeB6r+4|
$.N~AA~0
个PageUtil,负责对Page对象进行构造: H|)1T-%
java代码: :ky<`Jfr`
9$,gTU_a
P{Z71a5
/*Created on 2005-4-14*/ a!:8`X~[/$
package org.flyware.util.page; WDGGT.h G
;F""}wzn
import org.apache.commons.logging.Log; ^!<7#kX
import org.apache.commons.logging.LogFactory; 3N"&P@/0x
jDX<iX%e
/** ]`sIs= _[
* @author Joa M',D
* 6XAr8mw9
*/ AMd)d^;
publicclass PageUtil { bVeTseAG
--twkD
privatestaticfinal Log logger = LogFactory.getLog j?f <hQ
{~t4
(PageUtil.class); ww($0A`ek
qZJ*J+
/** o w_y
* Use the origin page to create a new page 6lWFxbh
* @param page e^NEj1
* @param totalRecords
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* @return 1mJ_I|98
*/ uvDoo6'
publicstatic Page createPage(Page page, int 1bJ]3\
~snF20
totalRecords){ PS(j)I3
return createPage(page.getEveryPage(), -?nT mzRc
m_$I?F0
page.getCurrentPage(), totalRecords); +qj*P9
} /HuYduGdP
WQ}!]$<"y
/** = (gmd>N
* the basic page utils not including exception eAsX?iaH
R-Q1YHUQM
handler )SX6)__
* @param everyPage 6rQpK&Jx
* @param currentPage v$m[#&O^V?
* @param totalRecords 0BCGJFZ{
* @return page OJsd[l3xR
*/ m6r )Z5}f
publicstatic Page createPage(int everyPage, int XLmMK{gs
H@MFj>~
currentPage, int totalRecords){ [-t> G!)
everyPage = getEveryPage(everyPage); '95E;RV&
currentPage = getCurrentPage(currentPage); )6>|bmpU
int beginIndex = getBeginIndex(everyPage, a*':W%7
K@P`_yxN
currentPage); EotwUT|
int totalPage = getTotalPage(everyPage, e?| URW
T]6c9_
totalRecords); V<vPFxC
boolean hasNextPage = hasNextPage(currentPage, 2]} Uov
+&7Kk9^
totalPage); ,=Nw(GI
boolean hasPrePage = hasPrePage(currentPage); F[CT l3X
k9)u3
returnnew Page(hasPrePage, hasNextPage, i6md fp|k
everyPage, totalPage, Yxd{&47
currentPage, 'dc+M9u)_q
lP*
beginIndex);
f5aF6FBH
} 6%kJDY.
bqrJP3
privatestaticint getEveryPage(int everyPage){ qggk:cN1
return everyPage == 0 ? 10 : everyPage; (~Uel1~@
} }@14E-N=
;}WtJ&y=M
privatestaticint getCurrentPage(int currentPage){ |[Ie.&)
return currentPage == 0 ? 1 : currentPage; ,MM>cOQ
} )@,90Vhh
1/2V.:bg
privatestaticint getBeginIndex(int everyPage, int #$=8g
RZj
H=&/ Q
currentPage){ WBr:|F+~s
return(currentPage - 1) * everyPage; 4Oy.,MDQP
} ojx'g8yO
bEBBwv
privatestaticint getTotalPage(int everyPage, int yQZ/,KX
*`ZB+ \*
totalRecords){ #*$_S@
int totalPage = 0; "J
pTE \/
-XVEV
if(totalRecords % everyPage == 0) Jq$_=X&
totalPage = totalRecords / everyPage; +YkW[a\4
else i_=?eUq%q/
totalPage = totalRecords / everyPage + 1 ; F#1 Kk#t
1l+kO,X]
return totalPage; 5L-lpT8P
} [0u.}c;(
EmX>T>~#D
privatestaticboolean hasPrePage(int currentPage){ 9zZ5Lr^21
return currentPage == 1 ? false : true; 8QVE_ Eu
} StU 4{
mDQEXMD
privatestaticboolean hasNextPage(int currentPage, [eNkU">}
|rHG%VnBH
int totalPage){
u>}w-
return currentPage == totalPage || totalPage == U g}8y8
!/Iq{2LX
0 ? false : true; 0]T.Lh$3
} rQ~ \~g[tP
B;Xoa,
ItI0x
} +@emX$cFV
ME$2P!o
q=6Cc9FN
yo\N[h7
EBoGJ_l
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 b
, juF2
M{?zvq?d
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 C.J`8@a]?
Oj4v#GK]
做法如下: 4\LZD{
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 `$s)X$W?
kSbO[)p
的信息,和一个结果集List: 4_PCqEp)
java代码: pOC% oj
f64(a\Rw!^
M1oPOC\0.
/*Created on 2005-6-13*/ $hkq>i \
package com.adt.bo; 5D,.^a1 A
|KL')&"
import java.util.List; XE_ir
Et
?y~TC qV
import org.flyware.util.page.Page; I=K!)X$
NO-k-
/** 10wvfRhng
* @author Joa ?X\3&Ujy$
*/ `|$'g^eCL
publicclass Result { {5^K Xj$B
\6{krn|
private Page page; qysTjGwa]
9G0D3F
private List content; s\[LpLt
KZ=u54
/** &V'519vmoZ
* The default constructor CuH2E>wz
*/ 7vn%kW=$
public Result(){ ~C&*.ZR
super(); 9O;cJ)tXY
} qG<7hr@x]
t\h$&[[l'z
/** pSHSgd~&
* The constructor using fields
#j;Tb2&w
* |%
z^N*
* @param page f-;$0mTQ
* @param content @q K]JK
*/ a1Hz3y~S/
public Result(Page page, List content){ *G9sy_
this.page = page; xwRhs!`t1
this.content = content; 9lf*O0Z&n
} 6{q;1-8j+j
<,"4k&0Q>V
/** +`@M*kd
* @return Returns the content. q\%cFB}
*/ <aJ$lseG
publicList getContent(){ ,`k_|//}=
return content; K]c4"JJ
} =;0wFwSz
!b8uLjd;
/** \v+u;6cx_
* @return Returns the page. <$%X<sDkq
*/ -$(Jk<
public Page getPage(){ jMM$ d,7B
return page; E@-ta):
} bLzs?eos
UXT
p
/** ~C-,G"zw&G
* @param content e,>%Z@92(
* The content to set. Lxv6!?v|
*/ a5@z:i
public void setContent(List content){ >nzu],U
this.content = content; UiH!Dl}<
} cvnB!$eji
,R?np9wc
/** (D<(6?
* @param page NQfYxB1Yr:
* The page to set. O.,3|
*/ !gF9k8\Yr$
publicvoid setPage(Page page){ ~*M$O &
this.page = page; r> k-KdS
} "g>.{E5
} )"Q*G/+2Ie
KzjC/1sd
c~0{s>
oc7$H>ET1
M*sR3SZ
2. 编写业务逻辑接口,并实现它(UserManager, mMSh2B
\ \06T`
UserManagerImpl) \P;rES'
java代码: o! OMm!
f$.?$
FS6<V0pil
/*Created on 2005-7-15*/ +uo{ m~_4
package com.adt.service; UH?
p]4Nz
'OkGReKt
import net.sf.hibernate.HibernateException; xe4Oxo
DZ$`
4;C[
import org.flyware.util.page.Page; W#'c5:m
4
08s_v=cF
import com.adt.bo.Result; lx |5?P
,E;;wdIt
/** )? =YT
* @author Joa BHA923p?
*/
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publicinterface UserManager { b>\?yL/%+?
zce`\ /:
public Result listUser(Page page)throws U!(@q!>G
{D`'0Z1"
HibernateException; S?ujRp
7%MbhlN.
} Y ^KTkS0D
uR;gVO+QC
#m<tJnEO
M;w?[yEZ
:~F :/5
java代码: fX~'Zk\u
aAE>)#f(
:#5xA?=*
S
/*Created on 2005-7-15*/ oVvc?P
package com.adt.service.impl; 2S"Nf8>zp
D&G"BZx|
import java.util.List; 2)X4y"l
vI1i,x#i
import net.sf.hibernate.HibernateException; Ea6
&~"
tZyo`[La
import org.flyware.util.page.Page; 0'5/K ,
import org.flyware.util.page.PageUtil; Rk6deI]
({s6eqMhDd
import com.adt.bo.Result; S4UM|`
import com.adt.dao.UserDAO; '1?\/,em
import com.adt.exception.ObjectNotFoundException; 1'.7_EQ4T
import com.adt.service.UserManager; z~*g ~RKS!
@"-</x3o
/** n">u mM;Eh
* @author Joa ;U9J++\d<A
*/ 5xCT~y/a
publicclass UserManagerImpl implements UserManager { 8:=n*
+Hvc_Av''
private UserDAO userDAO; P{OAV+cG
T9W`?A
/** rxnFrx
* @param userDAO The userDAO to set. p)aeH`;O
*/ =m89z}Ot
publicvoid setUserDAO(UserDAO userDAO){ _VE^/;$"l
this.userDAO = userDAO; 3`E=#ff%
} pM;vH]|
&H}r%%|A
/* (non-Javadoc) Wj|alH9<
* @see com.adt.service.UserManager#listUser gr-9l0u
}jH7iyjD
(org.flyware.util.page.Page) o?L'Pg
*/ YB<*"HxM)}
public Result listUser(Page page)throws ; Uc0o!1
qgIb/6;xQ
HibernateException, ObjectNotFoundException { >Y7a4~ufko
int totalRecords = userDAO.getUserCount(); &LO"g0w
if(totalRecords == 0) ]aP=Ks%
throw new ObjectNotFoundException :x.7vZzxs
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Htr<+
("userNotExist"); :y*NM,s
page = PageUtil.createPage(page, totalRecords); SIO&rrT.
List users = userDAO.getUserByPage(page); 7tUA>;++
returnnew Result(page, users); +#U|skl
} &Z(K6U#.
**9x?s
} F+R?a+e
^;!0j9"*:
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u:tbP
,.eWQK~
FZjHw_pP
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 lC:k7<0Ji
|4$M]M f0
询,接下来编写UserDAO的代码: b@RHc!,>jV
3. UserDAO 和 UserDAOImpl: `&\Q +W
java代码: X%z }VA
+$4(zPs@
dS^T$sz.co
/*Created on 2005-7-15*/ Vk<
LJ
S
package com.adt.dao; |*Z$E$k:
Lg8nj< TF
import java.util.List; zp\8_ U@
|,9JNm$
import org.flyware.util.page.Page; #/PA A
afjtn_IB
import net.sf.hibernate.HibernateException; !.2<| 24
8.F~k~srA
/** *6HTV0jv
* @author Joa COH<Tj
*/ J>fQNW!{
publicinterface UserDAO extends BaseDAO { mF` B#
UOQEk22
publicList getUserByName(String name)throws
+)JpUqHa
<: &*
HibernateException; a]Lp?
ga?*DI8w
publicint getUserCount()throws HibernateException; zdXkR]
$kR N
h6
publicList getUserByPage(Page page)throws OL4z%mDZi
Y5fLmPza
HibernateException; {U&.D
[{&
vJAZ%aW
} !9 fz(9
:W b j\
Ol4+_n8xj
2WUT/{:X
Uj&W<'I
java代码: xsWur(> ]
\*=7#Vd
'SQG>F Uy
/*Created on 2005-7-15*/ (sVi\R
package com.adt.dao.impl; nUkaz*4qU
'_|h6<.k[
import java.util.List; XL7h}
[M+f-kl
import org.flyware.util.page.Page; aF03a-qw<
cuOvN"nuNj
import net.sf.hibernate.HibernateException; [@yV!#2
import net.sf.hibernate.Query; =8U&[F
Q:J^"
import com.adt.dao.UserDAO; >X*Mio8P#
sz9L8f2
/** CI3XzH\IX*
* @author Joa `/Y{ l
*/
yf&7P;A
public class UserDAOImpl extends BaseDAOHibernateImpl re> rr4@
?%H):r
implements UserDAO { Y@PI {;!
cQ9q;r`%
/* (non-Javadoc) {Zp\^/
* @see com.adt.dao.UserDAO#getUserByName asJ)4ema
L(X6-M:
(java.lang.String) T#bu
V
*/ ZvcJK4hi
publicList getUserByName(String name)throws g-Pwp[!qkf
Web|\CH
HibernateException { OyqNLR
String querySentence = "FROM user in class fu~+8CE.
Bn>8&w/P
com.adt.po.User WHERE user.name=:name"; ^ns@O+Fk
Query query = getSession().createQuery eb*#'\~'
~on(3|$
(querySentence); ayAo^q
query.setParameter("name", name); >}(CEzc8
return query.list(); J,b&XD@m
} #A]-ax?Qc}
?
w^-
/* (non-Javadoc) y\&>ZyOY
* @see com.adt.dao.UserDAO#getUserCount() Wh&8pH:
*/ L/"0ws_
publicint getUserCount()throws HibernateException { LzYO$Ir:g
int count = 0; Y#g4$"G9
String querySentence = "SELECT count(*) FROM \W%UZs
id$Ul?z8
user in class com.adt.po.User"; 02Ia2e.f
Query query = getSession().createQuery <})'Y~i
7
[g/TB
(querySentence); P6MRd/y |
count = ((Integer)query.iterate().next gzeQ|m2]
hR.@b*q?R
()).intValue(); L<fvKmo(fw
return count; JgHM?AWg|
} `U2DkY&n
Mg^e3D1_
/* (non-Javadoc) o=nsy]'&
* @see com.adt.dao.UserDAO#getUserByPage umdG(osR
T~b>B`_
(org.flyware.util.page.Page) 29reG,>
*/ w |l1'
publicList getUserByPage(Page page)throws KM`eIw>8
}2ZsHM^]%
HibernateException { Ko^c|}mh*!
String querySentence = "FROM user in class `c'W-O/
Yq/.-4y
com.adt.po.User"; YBnA+l*
Query query = getSession().createQuery 'g9"Qv?0{`
[V}S<Xp
(querySentence); ]D,MiDph
query.setFirstResult(page.getBeginIndex()) 5aa<qtUjH
.setMaxResults(page.getEveryPage()); j^`hzh3S
return query.list(); (!:cen~|[
} A4ISNM7R[
J/3_C6UZ
} 'TAUE{{
Zy_V9j[n
M?;y\vS?.
+&["HoKg}&
b=/curl&
至此,一个完整的分页程序完成。前台的只需要调用 oHs2L-G
.$#rV?7
userManager.listUser(page)即可得到一个Page对象和结果集对象 ,k G>?4
mg,j:,
的综合体,而传入的参数page对象则可以由前台传入,如果用 8#Q$zLK42N
1 `KN]Nt
webwork,甚至可以直接在配置文件中指定。 D0BI5q
w;l<[q?_
下面给出一个webwork调用示例: Q3"}Hl2
java代码: CA +uKM^"6
%8~3M75$
$U/YR&vcw
/*Created on 2005-6-17*/ {8I. `U
package com.adt.action.user; %e@#uxm
pT$f8xJ
import java.util.List; r
6Q Q
/6_|]ijc
import org.apache.commons.logging.Log; :f$x Qr4Qz
import org.apache.commons.logging.LogFactory; uB7 V?A
import org.flyware.util.page.Page; bb
d.
%sRUh0AL
import com.adt.bo.Result; N;+[`l
import com.adt.service.UserService; [{X^c.8G)
import com.opensymphony.xwork.Action; ?:Bv
iF);/
)IJQeC
/** *FJZiPy
* @author Joa _.-;5M-
*/ OaL\w
D^
publicclass ListUser implementsAction{ 7h)iu9j
J"FC%\|
privatestaticfinal Log logger = LogFactory.getLog qL94SW;
)TmHhNo
(ListUser.class); ^OErq&`u
CXCpqcC
private UserService userService; Dnc<sd;
ce6__f5?
private Page page; C R|lt
,$eK-w
privateList users; \Y}3cE
mZUfn%QXb(
/* 3 LdQ]S
* (non-Javadoc) X*L;.@xA
* )P|[r
* @see com.opensymphony.xwork.Action#execute() ti &J
*/ 8?FbtBAn
publicString execute()throwsException{ HQ{JwW!m
Result result = userService.listUser(page); W}|'#nR
page = result.getPage(); <?D\+khlq
users = result.getContent(); Dn>%%K@0
return SUCCESS; WlYs~(=9
} Q%-di=
,E.' o=Z
/** ]
7 _`]7p
* @return Returns the page. y?SyInt
*/ nQGQWg`
public Page getPage(){ F V,4pi
return page; ,y%3mR_~
} _Ob@`
A0%}v*
/** =f(cH152T
* @return Returns the users. V
_c@ b%
*/ 3 R&lqxhg
publicList getUsers(){ _`#3f1F@[
return users; 1xc~`~
} yObuWDA9
al`3Lu0
/** kapC%/6"
* @param page z%/N!RLW
* The page to set. smm]6
*/ ]!IVz)<E&
publicvoid setPage(Page page){ }(<%`G6N
this.page = page; C.kxQ<
} ~n/
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*SO{\bu
/** +t2SzQ j>
* @param users
U?!>Nd
* The users to set. O 1oxZj
<
*/ A_;8IlW
publicvoid setUsers(List users){ j:w{;(1=W
this.users = users; KzQ3.)/q
} ]QuM<ms
!d&C>7nb
/** .SWt3|Pi5
* @param userService 2y%,p{="
* The userService to set. mYc.x
*/ 7u[j/l,
publicvoid setUserService(UserService userService){ Gy[O)PEEh
this.userService = userService; 3/#:~a9Q
} cJgBI(S5
} ,TRTRb;
\u&_sBLKV
.%zy`n
GQ_p-/p
R
\cLSf=
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, 0<TD/1wN
GHQ;hN:
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 kPjd_8z2n
QORN9SY
么只需要: r_YIpnJ
java代码: 7#<c>~
w{dIFvQ"$
|7KeR-
<?xml version="1.0"?> rDdzxrKg{
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork )NR Q2
BA=,7 y&;j
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ]m#5`zGK1|
4:9KR[y/
1.0.dtd"> {s3z"OV
8UkKU_Uso
<xwork> 0R0{t=VJZ
LB/C-n.`
<package name="user" extends="webwork- K 0hu:1l)
>E,U>@+
interceptors"> m4:^}O-#
T}3v(6ew4
<!-- The default interceptor stack name >h+349
9dzdrT
--> wDwH.~3!
<default-interceptor-ref 1T)Zh+?)}
`m.eM
name="myDefaultWebStack"/> )+H[kiN
y&_m4Zw"
<action name="listUser" B??J@+Nf
_hG;.=sr
class="com.adt.action.user.ListUser"> r ]>\~&?^F
<param R4Rb73o
,p;_\\<
name="page.everyPage">10</param> VYw%01#
<result IcIOC8WC
2 3KyCV5
name="success">/user/user_list.jsp</result> j6(?D*x
</action> u>pBB@
7DlOW1|
</package> )~jqW=d
2
K)Zlc0e
</xwork> #'4OYY.
E|:!Q8"%w
joul<t-
gh6d&ucQ^
!AJ]j|@VBd
iqW1#)3'R
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 $mGvJ*9
(5^ZlOk3
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。 %PJhy 2
ftBq^tC
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 $<p8TtI=YQ
h.K(P+h
oVCmI"'
I?Q+9Rmm`J
fa.0I~
我写的一个用于分页的类,用了泛型了,hoho F>gmj'-^
(c v!Y=]
java代码: !G_jGc=v
[0[M'![8M
BGzI
package com.intokr.util; @
\2#Dpr
amQz^^
import java.util.List; 7-_vY[)/
=l<iI*J.
M
/** uIMe
* 用于分页的类<br> 9N[EZhW
* 可以用于传递查询的结果也可以用于传送查询的参数<br> `B8tmW#
* nT#JOmv
* @version 0.01 x|eeRf|
* @author cheng 5jq=_mHt
*/ @6o]chJo
public class Paginator<E> { djT5X
privateint count = 0; // 总记录数 d77r9
privateint p = 1; // 页编号 N_75-S7Cm
privateint num = 20; // 每页的记录数 #fhEc;t
privateList<E> results = null; // 结果 ^%y`u1ab
{F|48P;J
/** .I$}KE)
* 结果总数 H;WY!X$x
*/ ezTZnutZ
publicint getCount(){ G[idN3+#
return count; .]Mn^2#j
} y|_Eu:
OY"6J@[z
publicvoid setCount(int count){ ZkB3[$4C=5
this.count = count; /,|CrNwY*
} 6gOe!mm
NBl
__q
/** NHX>2-b
* 本结果所在的页码,从1开始 \Btk;ivg
* [RU
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* @return Returns the pageNo. oQ+61!5>
*/ #f'DEo<b
publicint getP(){ Y@ F
return p; pw'wWZE'
} h7qBp300
MEwdw3
/** |)_-Bi;MW`
* if(p<=0) p=1 :u%$0p>
* ZI ?W5ISdg
* @param p 6ew "fCrH!
*/ 2H?d+6Pt3
publicvoid setP(int p){ n"aCt%v
if(p <= 0) wX1ig
p = 1; fMK#x\.4
this.p = p; H l j6$%.
} FquFRx
Tvf~P w
/** L*?!Z^k
* 每页记录数量 e&X>F"z2
*/ lj &>cScC
publicint getNum(){ Zzd/K^gg
return num; 8V4V3^_xs
} /c+)C"
nbd Gt
/** #\If]w*j
* if(num<1) num=1 %hT4qzJj
*/ aW5~Be$
_
publicvoid setNum(int num){ 7el<5chZ
if(num < 1) 9EF~l9`'U
num = 1; L~FTr
this.num = num; ACBQ3
} BH :
r>qA $zD^
/** _LfHs1g4
* 获得总页数 I6OSC&A`
*/ CdhSp$>
publicint getPageNum(){ |LYKc.xo
return(count - 1) / num + 1; &+nRIv S_`
} J l7z|Q S
H)JS0
G0
/** {sS_|sX
* 获得本页的开始编号,为 (p-1)*num+1 K^i"9D)A
*/ T'rjh"C&|
publicint getStart(){ Ex($
return(p - 1) * num + 1; 6GOcI#C9C
} V;9 }7mw
<lFY7'aY
/** m7 XjP2
* @return Returns the results. IKf`[_,t]
*/ )bWrd$X
publicList<E> getResults(){ O<,r>b,
return results; ,@Z_{,b
} a20w,
4'At.<]jL
public void setResults(List<E> results){ LR$z0rDEM
this.results = results; E5x]zXy4
} .1ddv4Hk
dl/X."iv!
public String toString(){ 2Ug.:![
StringBuilder buff = new StringBuilder kG3!(?:
r#~K[qb
(); I5pp "*u
buff.append("{"); t9*=
buff.append("count:").append(count); <lld*IH
buff.append(",p:").append(p); =l|>.\-
buff.append(",nump:").append(num); <NQyP{p
buff.append(",results:").append {$TZ}z"DA
E#h~V5Tf
(results); .Dv=pB,u
buff.append("}"); X!0kK8v
return buff.toString(); VJ1*|r,
} q`loOm=y
:Ee ?K
} Q#rt<S1zW
IrO+5 w
M]ap: