Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ?7Y6: zo$^
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ~$O.KF:
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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 X?'v FC
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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 }?0At<(d
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分页支持类: I}&`IUP
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java代码: rLU+-_
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package com.javaeye.common.util; ZT\=:X*e
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import java.util.List; Z?7XuELKV
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publicclass PaginationSupport { Vlk]
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publicfinalstaticint PAGESIZE = 30; _|!FhZ
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privateint pageSize = PAGESIZE; V@QWJZ"
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privateList items; yMQZulCWE
@w H+,]xE
privateint totalCount; Vh WF(*
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privateint[] indexes = newint[0]; <)vjoRv
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privateint startIndex = 0; K|n$-WDG}
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public PaginationSupport(List items, int |)7dh B
? ^EB"{
totalCount){ zj ?^,\{A
setPageSize(PAGESIZE); Y_H|Fl^
setTotalCount(totalCount); a<W[???m/M
setItems(items); ?W#>9WQi
setStartIndex(0); u9.x31^
} -W^jmwM
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public PaginationSupport(List items, int x2^Yvgc-
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B
totalCount, int startIndex){ 3(Y#*f|
setPageSize(PAGESIZE); *5\k1-$
setTotalCount(totalCount); z2Pnni7Ys
setItems(items); \5]${vs&s
setStartIndex(startIndex); MS Ml
} ?\
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public PaginationSupport(List items, int 1nt VM+
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totalCount, int pageSize, int startIndex){ `eF&|3!IYQ
setPageSize(pageSize); 4z_ >CiA
setTotalCount(totalCount); "I)*W8wTn
setItems(items); J73B$0FP
setStartIndex(startIndex); [_jd
} 8f^QO:
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publicList getItems(){ u9t@%H)lZ
return items; `*A!vO8
} 5BL4VGwJ
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publicvoid setItems(List items){ `W3;LTPEb
this.items = items; S690Y]:h$v
} "|2|Vju%
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publicint getPageSize(){ R::0.*FF
return pageSize; /``4!jU
} [>B`"nyNQ
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publicvoid setPageSize(int pageSize){ Kc6p||<
this.pageSize = pageSize; 2WP73:'t
} i.|zKjF'
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publicint getTotalCount(){ peA}/Jc
return totalCount; OZ/P@`kN.f
} Pl@3=s!~>~
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publicvoid setTotalCount(int totalCount){ Z*Sa%yf
if(totalCount > 0){ c
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this.totalCount = totalCount; aR
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int count = totalCount / '8auj
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pageSize; kl0!*j
if(totalCount % pageSize > 0) ;3nR_6\
count++; q'07
indexes = newint[count]; )zFPf]gz
for(int i = 0; i < count; i++){ &8l"Dl
indexes = pageSize * n/
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i; B,@<60u
} _TB,2 R
}else{ _K4Igq
this.totalCount = 0; d)G'y
} JGJXV3AT
} 7O_@b$Q
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publicint[] getIndexes(){ eV?._-G
return indexes; i2a""zac
} D{Zjo)&tF'
.|[5*-
publicvoid setIndexes(int[] indexes){ e|`QW|9 .
this.indexes = indexes; &\3k(j
} x*8lz\w
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publicint getStartIndex(){ C^}2::Qu
return startIndex; To x{Sk3L
} SJYy,F],V"
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publicvoid setStartIndex(int startIndex){ `zr%+
if(totalCount <= 0) *,/ADtL
this.startIndex = 0; //SH=>w2
elseif(startIndex >= totalCount) x@-bY
this.startIndex = indexes aoLYw 9
XZ@;Tyn0,
[indexes.length - 1]; lJ+05\pE
elseif(startIndex < 0) P/BWFN1
this.startIndex = 0; e <Hbm
else{ ;.=ZwM]C
this.startIndex = indexes O!0YlIvWv
3?Ml]=u
[startIndex / pageSize]; =hs
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} mSn>
} 24ojjxz+
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publicint getNextIndex(){ \DP*?D_}?
int nextIndex = getStartIndex() + )c'5M]V
Ca: jN0
pageSize; Tgpf0(
if(nextIndex >= totalCount) j,q8n`@
return getStartIndex(); P'.M.I@
else 8hx4s(1!
return nextIndex; 0!WF,)/T7i
} h$#QRH
K`=O!;
publicint getPreviousIndex(){ VDCG
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int previousIndex = getStartIndex() - '=|2, H]
=B}a +0u!
pageSize; #WBlEVx;Z
if(previousIndex < 0) _JlbVe[<
return0; taS2b#6\+
else )!h(o R
return previousIndex; /Iwnl
} ()< E?D=
RC_w 1:h
} OYw~I.Rq
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)7U^&I,
抽象业务类 sSisO?F!Z
java代码: e:SBX/\j
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/** w2-:!,X
* Created on 2005-7-12 <ptgFR+
*/ V SJGp`
package com.javaeye.common.business; tb^8jC
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import java.io.Serializable; sFqLxSo_I
import java.util.List; r(ej=aR
)E--E+j
import org.hibernate.Criteria; )ZxDfRjL
import org.hibernate.HibernateException; Xb0$BAP
import org.hibernate.Session; 72hN%l
import org.hibernate.criterion.DetachedCriteria; d|GQZAEJEt
import org.hibernate.criterion.Projections; (w31W[V'#
import Gp0H[-oF
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org.springframework.orm.hibernate3.HibernateCallback;
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import k)Y}X)\36
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org.springframework.orm.hibernate3.support.HibernateDaoS fE1B1j<
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upport; d~bZOy
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import com.javaeye.common.util.PaginationSupport; {!?
@u?M
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public abstract class AbstractManager extends _zAHN0d
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HibernateDaoSupport { w! J|KM
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privateboolean cacheQueries = false; 6OBe^/ZRt
)
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privateString queryCacheRegion; Vu
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publicvoid setCacheQueries(boolean VrV
)qfG
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cacheQueries){ y v6V1gK
this.cacheQueries = cacheQueries; ws"{Y+L
} ~}uv4;0l]
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publicvoid setQueryCacheRegion(String uvNLm]*
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queryCacheRegion){ 6f"jl
this.queryCacheRegion = l(c2 B
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queryCacheRegion; :O`7kZ]=n
} 4o+SSS
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publicvoid save(finalObject entity){ 4(
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getHibernateTemplate().save(entity); / z<7gd~oU
} ^$8@B]*
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publicvoid persist(finalObject entity){
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getHibernateTemplate().save(entity); pbfIO47ZC
} 9Fo00"q
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publicvoid update(finalObject entity){ ;^XF;zpg
getHibernateTemplate().update(entity); 12 8aJ
} H1?t2\V4
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publicvoid delete(finalObject entity){ SM57bN
getHibernateTemplate().delete(entity); }ufzlHD
} W<f-
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publicObject load(finalClass entity, &cZQ,o
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finalSerializable id){ QO1pwrX<
return getHibernateTemplate().load dTV4 Q`Z
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(entity, id); 1NHiW
v
} I5nxY)v
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publicObject get(finalClass entity, ` ,lm:x+(0
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finalSerializable id){ KCBA`N8
return getHibernateTemplate().get L/ L#[
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(entity, id); 5j8aMnv s
} /
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publicList findAll(finalClass entity){ Sb2hM~
return getHibernateTemplate().find("from /+V}.
s ;3k#-w
" + entity.getName()); ?*oBevUnCY
}
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publicList findByNamedQuery(finalString NO)Hi)$X6Y
]=gNA
namedQuery){ tTjadnX
return getHibernateTemplate fwF&V^Dy
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().findByNamedQuery(namedQuery); /M,C%.-
} yL2sce[
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publicList findByNamedQuery(finalString query, 1K*`i(
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finalObject parameter){ gGaA;YW1
return getHibernateTemplate 8v<802
)WBp.j /#
().findByNamedQuery(query, parameter); c)*,">$#
} ojc m%yd
n-"(lWcp
publicList findByNamedQuery(finalString query, >PYLk{q
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finalObject[] parameters){ qjBF]3%t%
return getHibernateTemplate Wg!<V6}
c-`'`L^J
().findByNamedQuery(query, parameters); }1xD*[W
} Cs!z3QU
w"Q/ 6#!K
publicList find(finalString query){ 1"\^@qRv#
return getHibernateTemplate().find !:]/MpQ ?
{4F=].!
(query); QZh#&Qf;
} +g9CklJ
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publicList find(finalString query, finalObject q`Rc \aWB%
.](~dVp%~
parameter){ @u>:(9bp
return getHibernateTemplate().find gzMp&J
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(query, parameter); KgH_-REN
} 1
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+ L\Dh.Ir
public PaginationSupport findPageByCriteria gmqL,H#
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(final DetachedCriteria detachedCriteria){ 5cF7w
return findPageByCriteria QmKEl|/{u
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x
(detachedCriteria, PaginationSupport.PAGESIZE, 0); Al
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} _:1s7EC
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public PaginationSupport findPageByCriteria ,q K'!
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(final DetachedCriteria detachedCriteria, finalint A{ a4;`}5
.)g7s? K
startIndex){ ?3_^SRW&a
return findPageByCriteria RM3"8J
Op_(10|
(detachedCriteria, PaginationSupport.PAGESIZE, TpGnSD
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startIndex); u2E}DhV
} vWH)W?2
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public PaginationSupport findPageByCriteria ,%T
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(final DetachedCriteria detachedCriteria, finalint Xk(p:^ R
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pageSize, :^En\YcU
finalint startIndex){ X()yhe_
return(PaginationSupport) 4T>d%Tt+)
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getHibernateTemplate().execute(new HibernateCallback(){ Jm`{MzqL
publicObject doInHibernate $xqX[ocor
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(Session session)throws HibernateException { M:*)l(
Criteria criteria = u.@B-Pf[Eo
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detachedCriteria.getExecutableCriteria(session); @@3%lr71
int totalCount = w }=LC#le
pf`vH`r
((Integer) criteria.setProjection(Projections.rowCount XS(Q)\"
.)c+gyaQ
()).uniqueResult()).intValue(); M^&^g
criteria.setProjection 2{xf{)hO?
sh/4ui{
(null); !BjJ5m
List items = B'-n
^';
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criteria.setFirstResult(startIndex).setMaxResults s^"*]9B"
zXW)v/
ZD
(pageSize).list(); &a'mh
PaginationSupport ps = j"
5 +"j
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new PaginationSupport(items, totalCount, pageSize, em9nuXG
cB6LJ}R
startIndex); $EnBigb!
return ps; AQGl}%k_
} XI>HC'.0
}, true); $}JWJ\-]
} >x*ef]aS
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public List findAllByCriteria(final Ys>Z=Eky
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DetachedCriteria detachedCriteria){ @Yw>s9X
return(List) getHibernateTemplate 6Zx)L|B
ncpNesB
().execute(new HibernateCallback(){ QT4&Ix,4T1
publicObject doInHibernate sdBB(
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(Session session)throws HibernateException { 2f5YkmGc";
Criteria criteria = f&I5bPS7}
}BWT21'-Y
detachedCriteria.getExecutableCriteria(session); F):1@.S
return criteria.list(); ODxCD%L
} eyuQ}R
}, true); 7 &iav2q
} J|u_45<
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public int getCountByCriteria(final Z4dl'v)9
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DetachedCriteria detachedCriteria){ 39bw,lRPV
Integer count = (Integer) @2~;)*
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getHibernateTemplate().execute(new HibernateCallback(){ YRyaOrl$<
publicObject doInHibernate skF}_
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(Session session)throws HibernateException { -
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Criteria criteria = zym6b@+jN
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detachedCriteria.getExecutableCriteria(session); l\37/Z
return MxqIB(5k
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criteria.setProjection(Projections.rowCount @!*I
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0.&-1pw
()).uniqueResult(); ;!B,P-Z"g
} bb}Fu/S
}, true); _2WW0
return count.intValue(); A$n:
} <m> m"|G
} !
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<=!FB8 .
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用户在web层构造查询条件detachedCriteria,和可选的 24k;.o
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 O f]/tdPp
sZ0)f!aH:_
PaginationSupport的实例ps。 HfEl
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ps.getItems()得到已分页好的结果集 a>&dAo}
ps.getIndexes()得到分页索引的数组 r`sG!
ps.getTotalCount()得到总结果数 XHm6K1mGZ
ps.getStartIndex()当前分页索引 De\Ocxx
ps.getNextIndex()下一页索引 kBtzJ#j B
ps.getPreviousIndex()上一页索引 lL,0IfC,
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ;pqS|ayl
v?l*jr1-2
,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 GQYB2{e>
1-.(pA'
一下代码重构了。 }?*$AVs2q
'VV"$`Fu"
我把原本我的做法也提供出来供大家讨论吧: <CWOx&hr
tlgg~MViS
首先,为了实现分页查询,我封装了一个Page类: ^*F'[!. p
java代码: 1aezlDc*
7>3+]njw
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/*Created on 2005-4-14*/ WH<\f|xR
package org.flyware.util.page; f%yNq6l
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/** <m*j1|^{t
* @author Joa `We?j7O
* l - ~PX
*/ MAD t$_
publicclass Page { {d%hkbN+{
+A1xqOB
/** imply if the page has previous page */ !.7m4mKzo
privateboolean hasPrePage; \"P$*y4Le
:ay`Id_tm
/** imply if the page has next page */ j07b!j:"\}
privateboolean hasNextPage; } a!HbH
cHJ4[x=
/** the number of every page */ Y8/&1s_
privateint everyPage; u6
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oN,9#*PVL
/** the total page number */ !gi3J @
privateint totalPage; zANsv9R~
tcD5"ALJ
/** the number of current page */ V]/$ dJ
privateint currentPage; :/6u*HwZh
>fp_$bjd
/** the begin index of the records by the current of>H&G)@
vb$i00?
query */ h5lngw
privateint beginIndex; 5s<.qDc
]3
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/** The default constructor */ D 1(9/;9
public Page(){ HFX,EE
_+<AxE9\
} G#3$sz
~I@ %ysR
/** construct the page by everyPage ~sTn?~
* @param everyPage ootkf=
* */ 1$ENNq#0
public Page(int everyPage){ -Zqw[2Q4
this.everyPage = everyPage; c@$W]o"A
} L"}2Y3
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/** The whole constructor */ v %S$5
public Page(boolean hasPrePage, boolean hasNextPage, -pQ0,/}K
uCj)7>}v{M
2,p= %
int everyPage, int totalPage, Zig3WiD&
int currentPage, int beginIndex){ +XAM2uN5_.
this.hasPrePage = hasPrePage; fwSI"cfM
this.hasNextPage = hasNextPage; RA}Y$ }^#'
this.everyPage = everyPage; `rpmh7*WV
this.totalPage = totalPage; a lyA#zao|
this.currentPage = currentPage; &&Otj-n5
this.beginIndex = beginIndex; C <H$}f
} zS `>65}e
> (W\Eh{J
/** E :UJ"6
* @return rji<g>GQ
* Returns the beginIndex. j#9n.i
%h
*/ z=TuUl@
publicint getBeginIndex(){ JR|P]}
return beginIndex; AZnFOS
} p e$WSS J
L7N>p4h]Xj
/** Bb7Vf7>
* @param beginIndex gh%Q9Ni-
* The beginIndex to set. T8Ye+eP}
*/ q]v{o8:U
publicvoid setBeginIndex(int beginIndex){ 2 '8I/>-
this.beginIndex = beginIndex; Sv[+~co<l
} V# JuNJ
2K2_-
/** B";Dj~y
* @return qcfg 55]'c
* Returns the currentPage. jNAboSf2Y
*/ r:,"k:C
publicint getCurrentPage(){ oMKG M@V
return currentPage; WISeP\:^
} *-s':('R
+`TwBN,kp-
/** p9eTrFDy?
* @param currentPage nu6v@<<F>
* The currentPage to set. [-1Yyy1}
*/ ]F4|@+\9
publicvoid setCurrentPage(int currentPage){ Y~UWUF%aK
this.currentPage = currentPage; nW ]T-!
} Su k;##I
|q 0iX2W
/** qO>A6
* @return vcSb:('
* Returns the everyPage. MwWN;_#EO)
*/ NZuylQ)0
publicint getEveryPage(){ ":L d}~>
return everyPage; Ar`U/ %Cu
} BsYJIKfW
sl*&.F,v=
/** OmaG|2u
* @param everyPage 4x" je
* The everyPage to set. R'aA\k-
*/ 8-)@q|
publicvoid setEveryPage(int everyPage){ }QJ6"s
this.everyPage = everyPage; sDXQ{*6a
} D#11
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|k)Nf+(}W
/** $wqi^q*)
* @return m[A$Sp_"-h
* Returns the hasNextPage. ,sn
9&E
*/ ZV`o:Gd
publicboolean getHasNextPage(){ I_na^sh*
return hasNextPage; ^/7Y3n!|3
} a7e.Z9k!
_@sSVh$+
/** 27UnH: =
* @param hasNextPage %kiPE<<x
* The hasNextPage to set. 6{2 9cX.
*/ \C`2z]V%
publicvoid setHasNextPage(boolean hasNextPage){ t,qz%J&a
this.hasNextPage = hasNextPage; 4M>E QF&
} } BnPNc[I
z?(QM:
/**
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* @return S[RVk=A1
* Returns the hasPrePage. 8&v%>wxR@
*/ {Pe+d3Eoo
publicboolean getHasPrePage(){ bYy7Ul6]
return hasPrePage; p;LF-R
} :JzJ(q/
''B}^yKEW
/** kDWvjT
* @param hasPrePage n<MreKixE
* The hasPrePage to set. :SVWi}:Co1
*/ iuEQ?fp
publicvoid setHasPrePage(boolean hasPrePage){ d'b q#r
this.hasPrePage = hasPrePage; %~qY\>
} JPkI+0
kSO:xS0 _N
/** ?^
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* @return Returns the totalPage. Med0O~T%
* $%5!CD1)
*/ DZV U!J
publicint getTotalPage(){ oqy}?<SQ
return totalPage; $~:|Vj5iZ\
} <O]B'Wc [
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/** \>
* @param totalPage /@]@Tz@'
* The totalPage to set. ]D|Hq4ug
*/ N"2P]Zr
publicvoid setTotalPage(int totalPage){ x: 2 o$+v3
this.totalPage = totalPage; .$"69[1H
} \rmge4`4
2-gI@8NPI
} TRQH{O\O
&y.6Hiy&
mjbV^^>
Y> PC>
IJofbuzw:
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 Nrk/_0^
Eb9{
个PageUtil,负责对Page对象进行构造: hB-<GGcO <
java代码: M}`G}*
b "5WsJ:'#
rfhvd wwD
/*Created on 2005-4-14*/ };]f 3
package org.flyware.util.page; 4GqE%n+ta~
W>rx:O+
import org.apache.commons.logging.Log; U,GY']J
import org.apache.commons.logging.LogFactory; TAZ+2S# #7
3Uni{Z]Q)
/** fnudu0k
* @author Joa |%5nV=&\
* %1e{"_$O9
*/ :faB7wduW;
publicclass PageUtil { -LEpT$v|
2f.4P]s`T
privatestaticfinal Log logger = LogFactory.getLog o'p[G]NQ1o
+v"%@lC};
(PageUtil.class); qn~:B7f
!gFUC<4bu
/** "SN+ ^`
* Use the origin page to create a new page VtJyE}
* @param page i{6wns?KMj
* @param totalRecords |iB
svI:
* @return %Dm:|><V$b
*/ /S&8%fb
publicstatic Page createPage(Page page, int K!_''Fg
"\1QJ
totalRecords){ W1p5F\ wt
return createPage(page.getEveryPage(), nN!R!tJPa
xsSX~`
page.getCurrentPage(), totalRecords); ^_pJEX
} 6*=7ifS
\o{rw0w0
/** t'L#8MJ
* the basic page utils not including exception Com`4>0>I
xzTF| Z\
handler qn|~z@"
* @param everyPage nV&v@g4Tt
* @param currentPage 9U~sRj=D
* @param totalRecords $|r
p5D6
* @return page !x1ivP
*/ s+XDtO
publicstatic Page createPage(int everyPage, int oY0`igH
f3HleA&&
currentPage, int totalRecords){ xEvm>BZi
everyPage = getEveryPage(everyPage); T&~7*j(|e
currentPage = getCurrentPage(currentPage); xl;0&/7e
int beginIndex = getBeginIndex(everyPage, c %.vI
\h 1 T/_4
currentPage); lT~A~O
int totalPage = getTotalPage(everyPage, ;OfZEy>7
wQ/Z:
totalRecords); *IBCThj
boolean hasNextPage = hasNextPage(currentPage, k>q}: J9V
F 5FzT^
totalPage); YUsMq3^&
boolean hasPrePage = hasPrePage(currentPage); m kHcGB!~
3Mt Alc0xp
returnnew Page(hasPrePage, hasNextPage, x$Tf IFy
everyPage, totalPage, =
~^
currentPage, MJ0UZxnl
(YH/#n1"{
beginIndex); (GI]Uyn
}
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gtV*`g
privatestaticint getEveryPage(int everyPage){ KHJk}]K
return everyPage == 0 ? 10 : everyPage; 3Y+
bIz!
} I`8jJpGA
5D%gDw+"
privatestaticint getCurrentPage(int currentPage){ zaoC
return currentPage == 0 ? 1 : currentPage; Wx-vWWx*Q
} eGh7 ,wngH
auT'ATW7i
privatestaticint getBeginIndex(int everyPage, int |=W=H6h*
hCKx%&[^7
currentPage){ FkJX)
return(currentPage - 1) * everyPage; 1xE*quhrh
} 8'6$t@oT9w
Jh)K0>R
privatestaticint getTotalPage(int everyPage, int cPm-)/E)i
Z-B b,8
totalRecords){ K{x FhdW
int totalPage = 0; ~^R?H S
U?d4 ^
if(totalRecords % everyPage == 0) Y94/tjt
totalPage = totalRecords / everyPage; &33.mdBH
else nlkQ'XGAI
totalPage = totalRecords / everyPage + 1 ; eq#x~O4
'{(/C?T
return totalPage; j1{\nP/
} cXo^.u
auS.q5
%
privatestaticboolean hasPrePage(int currentPage){ q=40l
return currentPage == 1 ? false : true; 1-bQ
( -
} n%YG)5;
1_z6O!rx
privatestaticboolean hasNextPage(int currentPage, ;c;n.o.)/#
5pI=K/-
int totalPage){ ST[+k
return currentPage == totalPage || totalPage == 2>bV+[@B
GxR, 3
0 ? false : true; {BlKVsQ
} Ud8*yB
';hTGLq\X
oz- k_9%
} 9?_ybO~Oq
OnKPD=<
AZTn!hrU
_p`@/[(|
s"solPw
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 bG6<=^
G]- wN7G
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 MlM2(/ok
f;"6I
做法如下: 4fCg{
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 -=A W. Zo
;dh8|ujh
的信息,和一个结果集List: \O7Vo<B&D
java代码: "<J%@
ToB^/
n[
5@{+V!o,
/*Created on 2005-6-13*/ Mn=5yU
package com.adt.bo; +.b@rU6H
)5Bkm{v3
import java.util.List; a} w%k
khW9n*
import org.flyware.util.page.Page; X0.-q%5
P6E=*^^m(
/** EdPN=
* @author Joa F|DKp[<]8
*/ ]U,K]y[Bj
publicclass Result { U|%y`PZ
k<M~co;L
private Page page; I:qfB2tL)O
n6a*|rE
private List content; 426)H_wx
8zRb)B+
/** %ycCNS
* The default constructor r_kw "9
*/ ab=s+[r1
public Result(){ hR$lX8
super(); IHg)xZ
} L#`9# Q
v0dFP0.;&
/** f~.w2Cna
* The constructor using fields /~LXY<-(
* ecH-JPm'
* @param page Z-{!Z;T)z
* @param content (&6C,O~n^.
*/ /I'n]
public Result(Page page, List content){ ?]=fC{Rh
this.page = page; lK?
Z38
this.content = content; / h6(!-"
} Z`?<A da
q-.e9eoc\
/** !vQ!_|g1
* @return Returns the content. 1@ j>2>i
*/ B=;pyhc
publicList getContent(){ J9LS6~
7
return content; I@=h|GM
} TgaDzF,j{A
LaZF=<w(
/** _e.b#{=9
* @return Returns the page. (jD..qMs#
*/ a .5s5g)8
public Page getPage(){ )Q\ZYCPOr
return page; K;f'&9-+i,
} ?;,Al`/^
'^l/e: (H3
/** ]k mOX
* @param content gkpNT)
* The content to set. wYf=(w\c
*/ ]
%*970
public void setContent(List content){ WRAW%?$
this.content = content; (%>Sln5hq
} NEO~|B*oDU
`~(C\+gUp
/** Siw9_c
* @param page r2T?LO0N{
* The page to set. LoG@(g&)
*/ Yi[dS`,d
publicvoid setPage(Page page){ t.pg;#
this.page = page; Uc0AsUu}?
} Q:~w;I
} @2_s;!K
+k"dN^K]D
Et'C4od s
wN)R !6
| 4I x2GD
2. 编写业务逻辑接口,并实现它(UserManager, 04;y%~,}U/
S'-<p<;D\B
UserManagerImpl) ZZC=
7FB
java代码: dW7dMx
Z-<v5aF
YeJ95\jf
/*Created on 2005-7-15*/ g]xZ^M+
package com.adt.service; 6\,^MI
)
WIlj
import net.sf.hibernate.HibernateException; FbM5Bqv
^@L[0Z`
import org.flyware.util.page.Page; U8-9^}DBA
~+>M,LfK
import com.adt.bo.Result; wZa;cg.-q
(r[<g*+3
/** A2&&iL=j/
* @author Joa f
5i`B*/
*/ =zA=D.D2
publicinterface UserManager { 1MJ]Gh]5
ID+'$u&
public Result listUser(Page page)throws nu0bJ:0aLd
dr6 dK
HibernateException; Xy*X4JJh^
\ b9,>
} na']{a1K
;(0:6P8I
`A
<yDy
UxicqkX
24N,Bo
3
java代码: Dlj=$25
N/?MsrZw
HHnabSn}{q
/*Created on 2005-7-15*/ MF\n@lX
package com.adt.service.impl; jX&&@zMq
\wRr6-!_
import java.util.List; \>=YxB q
J#V`W&\,6
import net.sf.hibernate.HibernateException; w78Ius,
lIjHd#q-C
import org.flyware.util.page.Page; Aq'%a)Y2
import org.flyware.util.page.PageUtil; =cC]8Pz?
cn\& ;55v
import com.adt.bo.Result; f!$J_dz
import com.adt.dao.UserDAO; >qF KXzI
import com.adt.exception.ObjectNotFoundException; sf*SxdoZU
import com.adt.service.UserManager; "(efd~.]
x#8=drh.:C
/** ,t+ATaOF
* @author Joa r3j8[&B"
*/ Zc4hjg
publicclass UserManagerImpl implements UserManager { ''v1Pv-
[S4\fy0
private UserDAO userDAO; pV("NJj!
w|nVK9.
/** ,;d9uG2
* @param userDAO The userDAO to set. mTP.W#N
*/ [d&Faa[`
publicvoid setUserDAO(UserDAO userDAO){ Fcr@Un'
this.userDAO = userDAO; 78QFaN$
} ?3Jh{F_+
2mlE;.}8
/* (non-Javadoc) $GO'L2oLwn
* @see com.adt.service.UserManager#listUser ^p7(
=hs@W)-O
(org.flyware.util.page.Page) PRz oLzr
*/ %xZ.+Ff%
public Result listUser(Page page)throws F{"%ey">
kN$70N7I;
HibernateException, ObjectNotFoundException { H0(zE*c~
int totalRecords = userDAO.getUserCount(); Fp]8f&l8
if(totalRecords == 0) -.*\J|S@g
throw new ObjectNotFoundException tJu<#hX
sMS`-,37u
("userNotExist"); "G,*Z0V5
page = PageUtil.createPage(page, totalRecords); %@&)t?/=
List users = userDAO.getUserByPage(page); &V:dcJ^Q
returnnew Result(page, users); ]czy8n$+
} )[K3p{4
ibuI/VDF
} |"-,C}O
~Op1NE
rka:.#!
UA8!?r-cR
h@DJ/&;u@
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 V0AX1?H~ w
>ATW/9r
询,接下来编写UserDAO的代码: kxmS
3. UserDAO 和 UserDAOImpl: |K_B{v.
java代码: f!J^vDl
%xfy\of+Nk
j&Aq^aI
/*Created on 2005-7-15*/ F:@Ixk?E
package com.adt.dao; }6bLukv
$ vjmW!
O
import java.util.List; $~YuS_sYg
-0X> y
import org.flyware.util.page.Page; )mPlB.
-&EmEXs%
import net.sf.hibernate.HibernateException; JgB# EoF
heKI<[8l
/** 2$o[
* @author Joa 0/ Ht;(
*/ 'oHR4O*
publicinterface UserDAO extends BaseDAO { _Nn!SE
.;:xx~G_Q
publicList getUserByName(String name)throws :}JZKj!}M
JB(;[# '~
HibernateException; R,\
r{@yrz
0c5_L6_z
publicint getUserCount()throws HibernateException; O%&@WrFq
\$C4H
publicList getUserByPage(Page page)throws SHk[X ]Uo
+Y~+o-_
HibernateException; W =zG
g=C<E2'i*
} E%^28}dN
yx2.7h3
}SV3PdE
v/czW\z
fI1;&{f
java代码: Du>HF;Fv
3I5WDuq
QRlzGRueR&
/*Created on 2005-7-15*/ Ng"vBycy
package com.adt.dao.impl; i-?zwVmn
@;6}xO2
import java.util.List; cWc)sb
$P(nh'\
import org.flyware.util.page.Page; #FB>}:L{h*
[!&k?.*;<
import net.sf.hibernate.HibernateException; A,{D9-%
import net.sf.hibernate.Query; xiF%\#N
M: "ci;*$
import com.adt.dao.UserDAO; rl%Kn^JJ~
9>R|k$`
/** 6EU4
* @author Joa \vsrBM
*/ 5gD)2Q6
public class UserDAOImpl extends BaseDAOHibernateImpl Y/0O9}hf
j>*SJtq7
implements UserDAO { $Jm2,Yv
hPxI&
:N
/* (non-Javadoc) `&_k\/
* @see com.adt.dao.UserDAO#getUserByName 1[l>D1F?
2NknC>9(\
(java.lang.String) @'*#]YU8
*/ CLfb`rF
publicList getUserByName(String name)throws !)3s <{k#
cf'}*$[S
HibernateException { -mJ&N
String querySentence = "FROM user in class ?0mJBA
0lCd,a2:
com.adt.po.User WHERE user.name=:name"; RuNH
(>Eb
Query query = getSession().createQuery ~Ls I<z
-^H5z+"^
(querySentence); ~{YgM/c|dt
query.setParameter("name", name); xD#I&.
return query.list(); o'7ju~0L
} #L.}CzAz
!2|`aa
/* (non-Javadoc) kA<r:/
* @see com.adt.dao.UserDAO#getUserCount() ?ev G=S4>
*/ 8MeXVhM
publicint getUserCount()throws HibernateException { P$/A! r
int count = 0; pMp9O/u%
String querySentence = "SELECT count(*) FROM 3Z:!o$
htYrv5q=M
user in class com.adt.po.User"; -Y=c g;
Query query = getSession().createQuery d:pm|C|F
%`T5a<
(querySentence); M3@fc,Ch
count = ((Integer)query.iterate().next 6Y)^)dOi
!*Z)[[
()).intValue(); e K1m(E.=
return count; pE/3-0;}N
} d4>-a^)V
8ex:OTzn|
/* (non-Javadoc) y/I~x+y
* @see com.adt.dao.UserDAO#getUserByPage q;../h]Ne
J+ZdZa}Ob
(org.flyware.util.page.Page) $lAb6e$n
*/ Q(5:~**I
publicList getUserByPage(Page page)throws 'eDgeWt/CQ
0nz@O^*g(
HibernateException { bC>>^?U1m
String querySentence = "FROM user in class /B@%pq
~wf~bzs
com.adt.po.User"; N E2sD
Query query = getSession().createQuery @b*T4hwA.
uAS8F=9xP
(querySentence); >?W;>EUH
query.setFirstResult(page.getBeginIndex()) Xb@z7X#O!
.setMaxResults(page.getEveryPage()); FP9<E93br
return query.list(); uU(G_E ?
} :.[5('
|vDoqlW
} ws2j:B
ENXW#{N.v
6a]f&={E
oB06{/6
0/P-> n~
至此,一个完整的分页程序完成。前台的只需要调用 W|rFl]~a
5;MK1l
userManager.listUser(page)即可得到一个Page对象和结果集对象 [{p?BTs
- )a_ub
的综合体,而传入的参数page对象则可以由前台传入,如果用 8pL>wL
&C
Ky9No"o
webwork,甚至可以直接在配置文件中指定。 XBWSO@M'
O4d^ig-xaH
下面给出一个webwork调用示例: xDA,?i;T
0
java代码: f+TBs_
z?uQlm*We
aRO_,n9
/*Created on 2005-6-17*/ @z$pPo0fW
package com.adt.action.user; D0y,TF
`-K)K<
import java.util.List; /zG-\e U
v(@+6#&
import org.apache.commons.logging.Log; S5E,f?l
import org.apache.commons.logging.LogFactory; OZB}aow
import org.flyware.util.page.Page; .A"T086
K~y9zF{
import com.adt.bo.Result; TaQ "G
import com.adt.service.UserService; .)^3t~
import com.opensymphony.xwork.Action; _/%]:
FQ|LA[~
/** n?e@):
* @author Joa o eJC
*/ Z!RRe]"y
publicclass ListUser implementsAction{ `YmI'
Q0q)n=i}]
privatestaticfinal Log logger = LogFactory.getLog )'
x/q
(m3I#L
(ListUser.class); nL+YL
W:{PBb"x8
private UserService userService; 1_j<%1{sZ
Tu=eQS|'
private Page page; @[>+Dzn[6
uU[[[LQq
privateList users; bV )PT`-,
J!A/r<
/* WrHgF*[
* (non-Javadoc) [Z5}2gB&
* \p3nd!OIG
* @see com.opensymphony.xwork.Action#execute() g=oeS%>E
*/ 76IALJ00V
publicString execute()throwsException{ yNqm]H3<MP
Result result = userService.listUser(page); DNm7z[t{
page = result.getPage(); X$uz=)
users = result.getContent(); q]iKz%|Z/
return SUCCESS; %KJhtd"q
} @q{:Oc^
k{}[>))Q
/** rtYb"-&
* @return Returns the page. ~E3SC@KL
*/ C:s^s
public Page getPage(){ `hK>bHj
return page; =N*%f%
} ND e[2
@ yg|OA}
/** c_-" Qo
* @return Returns the users. ?HEtrX,q
*/ J:~[j
publicList getUsers(){ p-Rm,xyL%
return users; -VreBKn
} 3lLW'g&=
XUQW;H
/** oieQ2>lYh
* @param page \~z?PA.$
* The page to set. mI?* Z%>g
*/ 7}#*3*]
publicvoid setPage(Page page){ y?*[}S
this.page = page; $/<"Si&(
} i)@U.-*5m
<@U.
/** \N`fWh8&
* @param users MAwC\7n+X
* The users to set. 9*-pden
l
*/ M\\e e3Ih
publicvoid setUsers(List users){ "UhK]i*@l
this.users = users; H IPcZ!p
} IFC%%It5,
0.J1!RIK/
/** {FV,j.D
* @param userService vB{;N
* The userService to set. .-('C> @
*/ k7yv>iN
publicvoid setUserService(UserService userService){ }sTH.%
this.userService = userService; (E"&UC[
} uKR\Xo}
} so?pA@O
cotxo?)Zv
o;M.Rt\A
|n|U;|'^
-!'Oy%a#
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, V_ +}^
F.~n
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 )){PBT}t]
&jXca| wAR
么只需要: 629~Uc6]
java代码: 9atjK4+o
Z;j/K
||{T5E-.F
<?xml version="1.0"?> 5YTb7M
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork *}
*!+C3
QQ^Gd8nQ
1.0//EN" "http://www.opensymphony.com/xwork/xwork- L~*|,h
xQNw&'|UU
1.0.dtd"> _dYf
P3wU#qU
<xwork> D rF
PtVo7zOye
<package name="user" extends="webwork- 86;+r'3p.
G*P[z'K=
interceptors"> h.4qlx|
ysSjc
<!-- The default interceptor stack name 38V $ <w
^3Z7dIUww
--> $
7UDz
<default-interceptor-ref UC8vR>e\
%+AS0 JhB
name="myDefaultWebStack"/> Cp .1/
YXczyZA`x
<action name="listUser" cPA~eZbX
7.wR"1p#
class="com.adt.action.user.ListUser"> wFK:Dp_^
<param MuDFdbtR
io1S9a(y
name="page.everyPage">10</param> \]Y\P~n
<result c8^+^.=pX
tyc8{t#Z
name="success">/user/user_list.jsp</result> WW@JVZxK
</action> MxM](ew~7
dIoF ~8V
</package> l?3vNa FeR
/M0l
p
</xwork> 3[MdUj1y[
:`:xP
RpHpMtvNo/
<MPeh&_3#
f|-
m ^/y
/HB+ami,
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 (\Rwf}gyR
C/mg46
v2W
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。 @MNl*~'$.[
[MV`pF)x
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 ry$tK"v/
*hv=~A
$q
_oQtk^fp
[GtcaX{Zz
+\+Uz!YS
我写的一个用于分页的类,用了泛型了,hoho th5,HO~
*e(:["v
java代码: T&o,I
m(2G*}
\w{@u)h
package com.intokr.util; xL9:4'I
AyE%0KmraK
import java.util.List; pp/#Am
8# 6\+R
/** ^36M0h|R
* 用于分页的类<br> VYL@RL'
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 6P0y-%[Gk
* cDfx)sL
* @version 0.01 LiiK3!^i
* @author cheng 4st~3,lR$
*/ t{+M|Y
public class Paginator<E> { o)0C-yO0qf
privateint count = 0; // 总记录数 77+|#<J
privateint p = 1; // 页编号 /uK)rG
F
privateint num = 20; // 每页的记录数 Bs_S.JP<`
privateList<E> results = null; // 结果 [?;`x&y~y
gsnP!2cR
/** X7e>Z)l
* 结果总数 qIB>6bv#x
*/ x$~3$E
publicint getCount(){ U'rr?,RML
return count; A|2 <A
!
} Q}WL/X5
V]r hr
publicvoid setCount(int count){ r %+Bc Y
this.count = count; ?lF mXZy`
} \|v `l{
V@B7P{gH
/** `Ac:f5a
* 本结果所在的页码,从1开始 +T-@5v[
* YKc>6)j
* @return Returns the pageNo. )V=0IZi
*/ 3 t/ R 2M
publicint getP(){ 6hp{,8|D"m
return p; I|H,)!Z
} 7 n\mj\
$2Ka u 1
/** iwvt%7
* if(p<=0) p=1 Vre=%bGw
* dAL0.>|`0
* @param p (RExV?:
*/ Kl2}o|b
publicvoid setP(int p){ #>BX/O*D
if(p <= 0) $+7 ci~gs
p = 1; *U
M!(
this.p = p; >H$;Z$o*(
} o1e4.-xI
3 sl=>;-
/** kmIoJH5
* 每页记录数量 I=U+GY:
*/ l(gJLjTH%
publicint getNum(){ 3QIdN
return num; -RGPtD@
} B#1:Y;Z
S)+CTVVE
/** UIQQ\,3
* if(num<1) num=1 ~
W@X-
*/ :]yg
publicvoid setNum(int num){ `Uv)Sf{
if(num < 1) JwjI{,jY
num = 1; ` ovgWv
this.num = num; `n6/ A)
} Sobtz}A*
2%5?Fn=
/** %Mh Q
* 获得总页数 <3lUV7!
*/ #$FY+`
publicint getPageNum(){ n"iNKR>nW
return(count - 1) / num + 1; CldDr<k3
} Mxo6fn6-46
h!v/s=8c
/** vmvFBzLR
* 获得本页的开始编号,为 (p-1)*num+1 ZBF1rx?
*/ ("OAPr\2dw
publicint getStart(){ vm|!{5l:=y
return(p - 1) * num + 1; W,DZ ;).%
} WK*S4c
R+d<
fe
/** w(Gz({l+
* @return Returns the results. kymn)Ea
*/
aV<^IxE;
publicList<E> getResults(){ xHHV=M2l(s
return results; &-=K:;x
} "NKf0F
V'j@K!)~xR
public void setResults(List<E> results){ 9_GokU P_
this.results = results; yQ'eu;+]
} ;@9e\!%
G)8ChnJa!m
public String toString(){ vnTq6:f#M
StringBuilder buff = new StringBuilder kQIfYtT
Q70bEHLA
(); .9OFryo
buff.append("{"); IfMpY;ow=
buff.append("count:").append(count); 9qr UM`z$g
buff.append(",p:").append(p); Z^*NnL.'
buff.append(",nump:").append(num); )yrAov\z*
buff.append(",results:").append ./7v",#*.'
Sl"BK0:%7
(results); K^aj@2K{
buff.append("}"); nS.2C>A
return buff.toString(); 9KyZEH;pY
} BRa{\R^I
9_UN.]
} +bUW!$G
-TTs.O8P|<
x#mtS-sw2Q