Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 T$;N8x[
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ~/kx
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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 rn8t<=ptH3
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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 v5o@ls
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分页支持类: zmMz6\ $
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java代码: gkyv[
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package com.javaeye.common.util; #r_&Q`!eU
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import java.util.List; D#,P-0+%
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publicclass PaginationSupport { <+c6CM$#}V
7&z`N^dz{
publicfinalstaticint PAGESIZE = 30; "ewB4F[
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privateint pageSize = PAGESIZE; kdrya
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privateList items; 5#U*vGVT
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privateint totalCount; FWbA+{8
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privateint[] indexes = newint[0]; mmj6YQ0a
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privateint startIndex = 0; IuQY~!
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public PaginationSupport(List items, int `<L6Q2Y>j
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totalCount){ ~^Y(f'{
setPageSize(PAGESIZE); |H4/a;]~
setTotalCount(totalCount); 3[L)q2;}$N
setItems(items); "K8<X
setStartIndex(0); 5b9>a5j1;
} -l!;PV S|
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public PaginationSupport(List items, int >Cjb|f3'i}
@: s |X
totalCount, int startIndex){ >aZ$x/U+Iw
setPageSize(PAGESIZE); QxmVImn"
setTotalCount(totalCount); @edi6b1W
setItems(items); \5%T'S@5
setStartIndex(startIndex); 0r+%5}|-K
} l%^'K%'b
c!BiGw,;
public PaginationSupport(List items, int /L1qdkG
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totalCount, int pageSize, int startIndex){ :B<lDcFKJ
setPageSize(pageSize); In)#`E` g.
setTotalCount(totalCount); &OiJJl[9
setItems(items); gn?
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setStartIndex(startIndex); UEJX0=
} }>w;(R
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publicList getItems(){ c4R6E~S
return items; S)[`Bm
} H!ZPP8]j>
or u.a
publicvoid setItems(List items){ Ve&(izIh
this.items = items; @^vVou_
} g|PVOY+|^
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publicint getPageSize(){ J0}OmNTzD
return pageSize; rBP!RSl1
} D'>yu"
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publicvoid setPageSize(int pageSize){ ;&|ja]r
this.pageSize = pageSize; TZq']Z)#
} :_tsS)Q2m
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publicint getTotalCount(){ 1x]U&{do
return totalCount; IiACr@[?e
} "YGs<)S
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publicvoid setTotalCount(int totalCount){ bf
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if(totalCount > 0){ _?3bBBy
this.totalCount = totalCount; +>oVc\$
int count = totalCount / aT#R#7<Eg
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pageSize; YXH9Q@Gn
if(totalCount % pageSize > 0) <BQ4x.[
count++; 6ZVJ2xs[%
indexes = newint[count]; .3,s4\.kT
for(int i = 0; i < count; i++){ JQ%`]=n(/
indexes = pageSize * iuq-M?1
GP uAIoBo
i; i` Es7 }
} }`yIO"{8n
}else{ :JqH.Sqk
this.totalCount = 0;
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} lhx6+w
} aU2O5 z&
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publicint[] getIndexes(){ EpeTfD
return indexes; "j9,3yJT
} 38%]GQ
s} ,p>8
publicvoid setIndexes(int[] indexes){ >U9*
this.indexes = indexes; jd=k[Yqr
} O'" &9
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publicint getStartIndex(){ {3C~cK{
return startIndex; &?*M+q34
} AFl]w'=
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publicvoid setStartIndex(int startIndex){ k:<yy^g$X
if(totalCount <= 0) u9e A"\s
this.startIndex = 0; r 9@W8](\
elseif(startIndex >= totalCount) j%b/1@I
this.startIndex = indexes O GrVy=rd
[,-MC7>]
[indexes.length - 1]; gmWRw{nS+
elseif(startIndex < 0) )2z
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this.startIndex = 0; VVvV]rU~
else{ :M1S*"&:
this.startIndex = indexes G6Z2[Ej1
4_`+&
[startIndex / pageSize]; .-[UHO05^8
} *:3flJt
} `Bnp/9q5
GLt#]I"LY
publicint getNextIndex(){ )=;0
int nextIndex = getStartIndex() + on+
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pageSize; 4W~pAruwr
if(nextIndex >= totalCount) KQ xKU?b1
return getStartIndex(); Uw5z]Jck
else &?/h#oF@\
return nextIndex; )`^t,x<S
} d$kGYMT"
s*:J=+D]G
publicint getPreviousIndex(){ "W|Sh#JF
int previousIndex = getStartIndex() - 3IZ^!J
7Rk eV
pageSize; $TL~SVHj;{
if(previousIndex < 0) _{KQQ5k\
return0; g%#"
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else >tqLwC."'
return previousIndex; 2IqsBK`
} w:Tz&$&Y$
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} $Dd IY}
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抽象业务类 }f<.07
java代码: ykxjT@[
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/** GNqw]@'Yf
* Created on 2005-7-12 U"A]b(54
*/ 'AE)&56
package com.javaeye.common.business; %:N6#;l M
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import java.io.Serializable; Zk)]=<H
import java.util.List; MSoLx' <
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import org.hibernate.Criteria; \D<rT)Tl
import org.hibernate.HibernateException; ~a4htj
import org.hibernate.Session; sYiegX`1c
import org.hibernate.criterion.DetachedCriteria; }?^5\ot u
import org.hibernate.criterion.Projections; R>To
L
import ?7'uo$
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org.springframework.orm.hibernate3.HibernateCallback; M&~3fRb4
import Z[yQKy
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org.springframework.orm.hibernate3.support.HibernateDaoS &p^S6h
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upport; kz(%8qi8&
@U_w:Q<9u
import com.javaeye.common.util.PaginationSupport; xpKD 'O=T
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public abstract class AbstractManager extends xXE/pIXw
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HibernateDaoSupport { SgHLs
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privateboolean cacheQueries = false; .ZFs+8qU>
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privateString queryCacheRegion; E#`=xg
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publicvoid setCacheQueries(boolean \Q|1I
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cacheQueries){ 3aQWzEnh
this.cacheQueries = cacheQueries; :t8(w>oW
} =M>1;Qr<Z/
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publicvoid setQueryCacheRegion(String =2BGS\$#
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queryCacheRegion){ E5UI
this.queryCacheRegion = Xa.Qt.C
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queryCacheRegion; # nwEF QA
} n|Iy
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publicvoid save(finalObject entity){ w-2p'u['Z
getHibernateTemplate().save(entity); ns9iTU)
} znw\Dn?g
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publicvoid persist(finalObject entity){ Qa~o'
getHibernateTemplate().save(entity); 6&S;Nrg9
} (n05MwKu\
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publicvoid update(finalObject entity){ CDQ}C=4
getHibernateTemplate().update(entity); N0oBtGb
} :D8V*F6P
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publicvoid delete(finalObject entity){ Eg-3GkC
getHibernateTemplate().delete(entity); B\wH`5/KW
} sWP5=t(i+9
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publicObject load(finalClass entity, Cb7f-Eag
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finalSerializable id){ A,{X<mLFb
return getHibernateTemplate().load <f &z~y=
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(entity, id); X(U
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} ?~$0;5)QC
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publicObject get(finalClass entity, TYGUB%A
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finalSerializable id){ qv y~b
return getHibernateTemplate().get !Low%rP
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(entity, id); t8DySFT
} iUJqAi1o
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cf
publicList findAll(finalClass entity){ Q3vC^}Dmr
return getHibernateTemplate().find("from uV!Ax*'
L}*:,&Y/
" + entity.getName()); NK2Kw{c"iI
} i[/g&fx
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publicList findByNamedQuery(finalString tT'*Uu5
>j5)
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namedQuery){ uo;aC$US
return getHibernateTemplate 9>\P]:
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().findByNamedQuery(namedQuery); ,f8<s-y4Sg
}
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publicList findByNamedQuery(finalString query, \Z-T)7S
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@
finalObject parameter){ 55MrsiW
return getHibernateTemplate _\hZX|:]
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().findByNamedQuery(query, parameter); YhYcqE8
} 17AJT
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publicList findByNamedQuery(finalString query, mr
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finalObject[] parameters){ r|wB&
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return getHibernateTemplate }CnqJ@>C5
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().findByNamedQuery(query, parameters); 7p%W)=v
} knrR%e;
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publicList find(finalString query){ ++d(}^C;
return getHibernateTemplate().find xdb9oH
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hh
(query); 1t haQ"
} <7N8L
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publicList find(finalString query, finalObject \g<9_
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parameter){ Vw.c05 x
return getHibernateTemplate().find X~ |P
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(query, parameter); ):OGhWq
} 86igP
~CiVLSH=
public PaginationSupport findPageByCriteria ~L $B]\/A5
_i{$5JJ+K2
(final DetachedCriteria detachedCriteria){ S`HshYlE q
return findPageByCriteria =!u9]3)
)';Rb$<Qn
(detachedCriteria, PaginationSupport.PAGESIZE, 0); 5$Lo]H*
} M\O6~UFq!
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public PaginationSupport findPageByCriteria
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(final DetachedCriteria detachedCriteria, finalint 0f~7n*XH
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startIndex){ `X[L62D
return findPageByCriteria m8'B7|s
I{Hl2?CnI,
(detachedCriteria, PaginationSupport.PAGESIZE, y3l3XLI*b
i(P/=B
startIndex); 1cPm $=B
} jY>|>]4X
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public PaginationSupport findPageByCriteria 7KIOI,qb6
L".Qf|b*
(final DetachedCriteria detachedCriteria, finalint YoiM\gw
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pageSize, 6(Za}H
finalint startIndex){ *#+e_)d
return(PaginationSupport) 3]xe7F'`
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getHibernateTemplate().execute(new HibernateCallback(){ *lHI\5
publicObject doInHibernate @i'24Q[6
:K&>
(Session session)throws HibernateException { 62lG,y_L
Criteria criteria = mUW|4zl i}
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detachedCriteria.getExecutableCriteria(session); Q79& Q04XN
int totalCount = \Y.&G,?
5sJi- ^
((Integer) criteria.setProjection(Projections.rowCount '}\{4Qst
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()).uniqueResult()).intValue(); O%? TxzX;
criteria.setProjection .Rt_j
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(null); v~^c-]4I
List items = ?^]29p_
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criteria.setFirstResult(startIndex).setMaxResults w5*?P4P
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(pageSize).list(); )zw}+z3st
PaginationSupport ps = ,Q|[Yr
]~S,K}T
new PaginationSupport(items, totalCount, pageSize, }p-<+sFo
ly`p)6#R=
startIndex); C =fs[
return ps; Y4*ezt:;Q
} +g36,!q
}, true); 'Okitq+O
} *p!K9$4
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public List findAllByCriteria(final hKq <e%oVH
vqh@)B+)
DetachedCriteria detachedCriteria){ r~q*E'n
return(List) getHibernateTemplate s+Qm/ h2
s@C KZ`
().execute(new HibernateCallback(){ 9L3#aE]C
publicObject doInHibernate c%1<O!c
*&p `8:
(Session session)throws HibernateException { zTi%j$o
Criteria criteria = `P1jg$(eA
2yqm$i9C
detachedCriteria.getExecutableCriteria(session); NJJsg^'
return criteria.list(); >XzCHtEP
} v4]7"7GuW
}, true); d"zbY\`
} uv*OiB"
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public int getCountByCriteria(final pT Yq#9
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DetachedCriteria detachedCriteria){ 2w`k h=
Integer count = (Integer) v~-z["=}!
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getHibernateTemplate().execute(new HibernateCallback(){ 4u5^I;4pL
publicObject doInHibernate :ie7HF
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(Session session)throws HibernateException {
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Criteria criteria = S0.
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detachedCriteria.getExecutableCriteria(session); PMr
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return S-^y;#=
`_{'qqRhe
criteria.setProjection(Projections.rowCount .<JD'%?"
"B`yk/GM]
()).uniqueResult(); e6s-;
} nA8]/r1k
}, true); YpQ/ )fSEV
return count.intValue(); zjd]65P
} dtJaQ`
} +gb2>fei&
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用户在web层构造查询条件detachedCriteria,和可选的 Alh"G6
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 k#k !AcC
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PaginationSupport的实例ps。 Nx4_Oc^hY
PN0l#[{EN
ps.getItems()得到已分页好的结果集 N*JWd
ps.getIndexes()得到分页索引的数组 .Ajs0 T2
ps.getTotalCount()得到总结果数 ^T\JFzV
ps.getStartIndex()当前分页索引 Ikiv+Fq(
ps.getNextIndex()下一页索引 (mXV5IM
ps.getPreviousIndex()上一页索引 ,2u-<8
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 )_!t9gn*wr
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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 l= 5kd.{
xy`aR< L
一下代码重构了。 C/dqCUX:
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我把原本我的做法也提供出来供大家讨论吧: =g'7 xA
Mj5=t:MI
首先,为了实现分页查询,我封装了一个Page类: *ie#9jA
java代码: m;o \.s
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/*Created on 2005-4-14*/ ^!H8"CdC3
package org.flyware.util.page; pLMki=.Ld
'3=[xVnv
/** Uxx=$
* @author Joa OI B~W
* u{=(]n
*/ 'LIJpk3J
publicclass Page { Q%~b(4E^7P
{>>ozB.
/** imply if the page has previous page */ p"ht|x
privateboolean hasPrePage; FCQI fJ#
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/** imply if the page has next page */ !$hrK6o
privateboolean hasNextPage; ~$w-I\Q!
k{Yj!C>
#
/** the number of every page */ 4VLrl8$K
privateint everyPage; cF_`m
5{qFKo"g@,
/** the total page number */ [r_,BH\nu
privateint totalPage; m *8[I
l){l*~5zl2
/** the number of current page */ [La=z7*
privateint currentPage; +jzpB*@
1g{`1[.QO
/** the begin index of the records by the current 0rY<CV;fZ
9ZUG~d7_
query */ JE,R[` &
privateint beginIndex; E,E:W uB
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csT_!sII
/** The default constructor */ u$x HiD
public Page(){ Ac<V!v71
]hTYh^'e
} X<ZIeZBn
)K>XLaG)
/** construct the page by everyPage u*`acmS>N
* @param everyPage *>rpcS<l
* */ rP,i,1Ar 4
public Page(int everyPage){ /Q5pAn -u
this.everyPage = everyPage; %).phn"ij[
} <||F$t
i{PRjkR
/** The whole constructor */ #B:J7&@fn
public Page(boolean hasPrePage, boolean hasNextPage, K^?yD
VcIsAK".4[
V|
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int everyPage, int totalPage, \\
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int currentPage, int beginIndex){ LlL\7?_;
this.hasPrePage = hasPrePage; eSoOJ[&$
this.hasNextPage = hasNextPage; Wcn3\v6_
this.everyPage = everyPage; Y&`Vs(
this.totalPage = totalPage; $bh2zKB)
this.currentPage = currentPage; 2fTkHBhn&
this.beginIndex = beginIndex; ~}w(YQy=y
} &$jg *Kr
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/** qO[6?q=c:
* @return 3Gf^IV-
* Returns the beginIndex. A_T-]YQ
*/ zMt "ST.
publicint getBeginIndex(){ g"(
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return beginIndex; Y'S xehx
} EnA) Rz
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/** Xj"/6|X
* @param beginIndex LslQZ]3MY
* The beginIndex to set. `R0>;TdT
*/ L 7_Mg{
publicvoid setBeginIndex(int beginIndex){ U2/H,D
this.beginIndex = beginIndex; 5.F.mUO
} @no]*?Gpa
%m!o#y(hD`
/** (qlIQC
* @return Q[scmP^$^
* Returns the currentPage. Df02#493
*/ zC!]bWsD
publicint getCurrentPage(){ z|F>+6l"Y7
return currentPage; tc\LK_@$/F
} j{>E.F2.
k!t5>kPSQ
/** Fp+^`;j
* @param currentPage uDK`;o'F
* The currentPage to set. inZMq(_@$
*/ D4G*K*z,w4
publicvoid setCurrentPage(int currentPage){ &D[dDUdHs
this.currentPage = currentPage; KM< +9`
} COc1np
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/** ^i&/k
* @return rw8O<No4.o
* Returns the everyPage. uCF+Mp
*/ 7<x0LW
publicint getEveryPage(){ AUcq\Ys
return everyPage; |OF<=GGO+
} ;#78`x2
-aLBj?N c[
/** M:6H%6eT
* @param everyPage "w=p@/C
* The everyPage to set. DUEA"m h
*/ j\q1b:pE
publicvoid setEveryPage(int everyPage){ wd~e3%JM
this.everyPage = everyPage; ,!F'h:
} ?+D_*'65D
%MU<S9k
/** 1sYwFr 5
* @return HB {w:
* Returns the hasNextPage. (<s7X$(]e
*/ R+P,kD?
publicboolean getHasNextPage(){ xO9,,w47
return hasNextPage; $%`OJf*k
} )9##mUt'}
dP
T)&
/** f|WNPFQ$x
* @param hasNextPage 'SYj Ehvw
* The hasNextPage to set. n7
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*/ muT+H(Z p}
publicvoid setHasNextPage(boolean hasNextPage){ `5<
this.hasNextPage = hasNextPage; UY*Hc
} 2$yKa5SaX
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/** i' %V}2
* @return >*,Zc
* Returns the hasPrePage. {a `kPfP
*/ :m_0WT
publicboolean getHasPrePage(){ 6S])IA&VJ
return hasPrePage; 5ap}(bO
} Y~dRvt0_w
)M#~/~^f+
/** |Q`}a %
* @param hasPrePage }C"EkT!F
* The hasPrePage to set. 60[f- 0X
*/ PDREwBX
publicvoid setHasPrePage(boolean hasPrePage){ +Nv&Qu%
this.hasPrePage = hasPrePage; &.an-
} Ooc,R(
i
cQsA
/** lEQ63)Z
* @return Returns the totalPage. J;+tQ8,AP
* S"CsY2;
*/ 1m|Oi%i4
publicint getTotalPage(){ }<uD[[FLB
return totalPage;
?Vbe
} 9Vxsv*OR,
$.R$I&U
/** r&A#h;EQX2
* @param totalPage ;dRTr *
* The totalPage to set. ? =_l=dR
*/ 3*CF !Y%
publicvoid setTotalPage(int totalPage){ <\8dh(>
this.totalPage = totalPage; =:P9 $
} @Rig@
93kSBF#
} Cj"k
Fq4
#AyM!
@bmu4!"d
SY`NZJK
f5
wn`a~h
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 hx+a.N
kMo;<Z
个PageUtil,负责对Page对象进行构造: L'J$jB5cP
java代码: mJc'oG-
P%xk
1Nx%uz
/*Created on 2005-4-14*/ 9j49#wG0"B
package org.flyware.util.page; $f_;>f2N
*hF5cM[
import org.apache.commons.logging.Log; ?:s `}b
import org.apache.commons.logging.LogFactory; zbddn4bW9
$d:/cN
8E
/**
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* @author Joa VHM ,W]
* |n=m8X
*/ p !AQ
publicclass PageUtil { 1oFU4+{ 4
B*zb0hdo:
privatestaticfinal Log logger = LogFactory.getLog {}D8Y_=9\
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p
(PageUtil.class); nrUrMnlg
9^4^EY#
/** Sl:Qq!
* Use the origin page to create a new page N1\u~%AT"
* @param page ]8htJ]<|Q
* @param totalRecords C;oP"K]4=
* @return )U>q><
*/ +VdYT6{p
publicstatic Page createPage(Page page, int ) Y\} ,O
NlU:e}zGR
totalRecords){ 16ke CG\
return createPage(page.getEveryPage(), J}i$ny_3OB
rxI?|}4
page.getCurrentPage(), totalRecords); 8|d lt$
} j08G-_Gjn
FnP/NoZa>
/** uB
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* the basic page utils not including exception tJUMLn?
U/&?rY^|
handler $ZK4Ps -$
* @param everyPage GTYGm
* @param currentPage D(~6h,=m
* @param totalRecords |LcN_,}6
* @return page 8/-GrdyE
*/ \kzxt/Ow
publicstatic Page createPage(int everyPage, int G( nT.\
I=D`:u\H
currentPage, int totalRecords){ >
9JzYI^
everyPage = getEveryPage(everyPage); _Eq:Qbw#
currentPage = getCurrentPage(currentPage); \$VtwVQ,b
int beginIndex = getBeginIndex(everyPage, yh]#V"W3
X3!btxa%t
currentPage); bRLmJt98P
int totalPage = getTotalPage(everyPage, *Mg=IEu-6[
jzI\Q{[m'
totalRecords); ~~;fWM '
boolean hasNextPage = hasNextPage(currentPage, GJy><'J,!>
00%$?Fyk
totalPage); ro}plK(<WQ
boolean hasPrePage = hasPrePage(currentPage); >J 3N,f
w]"Y1J(i
returnnew Page(hasPrePage, hasNextPage, >LgV[D#=&o
everyPage, totalPage, s)375jCga
currentPage, 9C-F%te7
"2'nLQ""q
beginIndex); d7It}7@9
} W2%(a0p
@-qxNw
privatestaticint getEveryPage(int everyPage){ {u9(qd;;
return everyPage == 0 ? 10 : everyPage; fF_1ZKx+#!
} kkyn>Wxv
V*5:Vt7N
privatestaticint getCurrentPage(int currentPage){ RT)0I;
return currentPage == 0 ? 1 : currentPage; lh7{2WQ
} T_[W=9
>`5iq.v
privatestaticint getBeginIndex(int everyPage, int n2Dnpe:
O(~`fN?n
currentPage){ Q'*-gg&)
return(currentPage - 1) * everyPage; }}cVPB7
} BtBy.bR
HpDU:m
privatestaticint getTotalPage(int everyPage, int @2CYv>
l"IBt:
totalRecords){ %Q1v8l.}
int totalPage = 0; R@=ve
%a-
Rk"VFe>r
if(totalRecords % everyPage == 0) &I:X[=;g
totalPage = totalRecords / everyPage; Gd%6lab
else 6\\B{%3R2
totalPage = totalRecords / everyPage + 1 ; ]o6yU#zn~e
#bsR L8@
return totalPage; KT{<iz_
} RNRMw;cT
E0ud<'3<
privatestaticboolean hasPrePage(int currentPage){ 6xk"bIp
return currentPage == 1 ? false : true; 9{70l539
} /-^gK^
WE|L{
privatestaticboolean hasNextPage(int currentPage, fS1N(RZ1
y"cK@sOo
int totalPage){ `Wn0v2@a(~
return currentPage == totalPage || totalPage == Ea!}r|~]0
#8;^ys1f
0 ? false : true; V,|l&-
} m ~fqZK
y<BiR@%,7
A{x&5yX8
} ]8+%57:E
/:ma}qGy
NZ{kjAd3c
L@CN0ezQs
jn]hqTy8
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 duXv
[1
nP 2 rN_:4
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 eff6=DP
^._)HM
做法如下: n_$lRX5
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ?tqTG2! (
e>nRJH8pK
的信息,和一个结果集List: H$(%FWzQ%
java代码: "}7K>|a
kVkV~
@ewQx|
/*Created on 2005-6-13*/ o[+1O
package com.adt.bo; v :6`(5
$'L(}gNv5
import java.util.List; [%P_
Y/
Tud[VS?99
import org.flyware.util.page.Page; ;lW0p8
0u'2f`p*
/** TQE 3/I L
* @author Joa OjJlGEl w
*/ (mt,:hX
publicclass Result { [g=yuVXNZZ
}4cLU.L8O
private Page page; U
g]6i+rp
d";+8S
private List content; cFGP3Q4{
!uO|1b
/** Ywr^uy1V,/
* The default constructor t.lm`=
*/ A[htG\A` 0
public Result(){ l=
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super(); >W.Pg`'D
} B964#4&
9
>I]t|RT])
/** Z7k {7
* The constructor using fields 5y}}?6n+
* RBt"7 '
* @param page j\@s pbE@
* @param content iknB c-TLD
*/ 9Hlu%R
public Result(Page page, List content){ hd/5*C{s
this.page = page; qIA!m
.GC
this.content = content; f
IQ$a>
} !?O:%QG
)"t=sFxaB
/** bC?t4-W
* @return Returns the content. Wj.)wr!
*/ =]-!
publicList getContent(){ c!{.BgGN
return content; pR`.8MMc8
} 9zi/z_G
H'?Bx>X
/** -("79v>#
* @return Returns the page. Pa0tf:
*/ jY87NHg
public Page getPage(){ s67$tlV
return page; ;Qk* h'}f
} Rp}6}4=d
d cPh@3
/** @_1$
<8
* @param content k5g\s9n]
* The content to set. =J0FT2 d
*/ DrHMlk5
public void setContent(List content){ LeQ2,/7l:
this.content = content; gOgG23 x
} Qi6vP&
Zm&Zz^s
/** 8{%/!ylJz
* @param page L!mQP
* The page to set. akJ{-
*/ mQVduG
publicvoid setPage(Page page){ 1m}'Y@I
this.page = page; rZ:
} &rcr])jg[
} W
86S)+h
'qQDM_+
!Aunwq^
?D57HCd`n
\m5:~,p=
2. 编写业务逻辑接口,并实现它(UserManager, 4\Y=*X
[RC|W%<Z>
UserManagerImpl) I>L
lc Y
java代码: jqb,^T|j;m
\
{"8(ELX
kJJQcjAP:
/*Created on 2005-7-15*/ .7~Kfm@2
package com.adt.service; oUltr
:T%,.sH
import net.sf.hibernate.HibernateException; (Clf]\_II
k(%RX_]C
import org.flyware.util.page.Page; $dorE~T
F3';oyy
import com.adt.bo.Result; rAP+nh ans
j1**Ch/
/** *Vv ;NA/
* @author Joa E<-}Jc1
*/ 4zJ9bF4
publicinterface UserManager { "/ @
;6
P4R.~J ;8
public Result listUser(Page page)throws /xrt,M@
nfRo:@
HibernateException; ,1^)JshZ~
zs[t<`2
} O!Mm~@MoA
Pbm;@V
Wd~}O<"
9FPl
Cv;z^8PZJz
java代码: `n5RDz/f0
z0g$+bhy
bgYM
/*Created on 2005-7-15*/ $Cc4Sggq
package com.adt.service.impl; ;h/Y9uYn
_IT,>#ba
import java.util.List; 8b6:n1<fn
F^`sIrZvs
import net.sf.hibernate.HibernateException; P5] cEZ n
*$ ^ME
import org.flyware.util.page.Page; nU`vj`K
import org.flyware.util.page.PageUtil;
"thfd"-
&W.tjqmw
import com.adt.bo.Result; 1(On.Y=
import com.adt.dao.UserDAO; -pg7>vO q
import com.adt.exception.ObjectNotFoundException; 4XX21<yn
import com.adt.service.UserManager; Fo~C,@/Qt
2<u vz<B
/** Z( xn-
* @author Joa V :d/;~
*/ hDmVv;M:
publicclass UserManagerImpl implements UserManager { &,NHk9.aq
YdC:P#
Nf
private UserDAO userDAO; J0o U5d=3
_ogT(uYyr
/** e[Q(OV5(R
* @param userDAO The userDAO to set. H~x0-q<8
*/ Eq'{uV:
publicvoid setUserDAO(UserDAO userDAO){ zg8m(=k'
this.userDAO = userDAO; IXd&$h]Lq
} ~j F5%Gu
r"5]U`+
/* (non-Javadoc) $2;YJjz(
* @see com.adt.service.UserManager#listUser
n-H0cm
g*Cs/w
(org.flyware.util.page.Page) 2Ybz`O!
*/ ,:=E+sS
public Result listUser(Page page)throws "#[Y[t\Ia
x`C;
HibernateException, ObjectNotFoundException { k`\DC\0RG
int totalRecords = userDAO.getUserCount(); CgEeO,N]j
if(totalRecords == 0) 7p u*/W~
throw new ObjectNotFoundException FUq@
dUv
9W'#4
("userNotExist"); .lTGFeJqZ4
page = PageUtil.createPage(page, totalRecords); p(f)u]1`
List users = userDAO.getUserByPage(page); 3y 0`G8P'h
returnnew Result(page, users); -qx Z3
} Kj-:'jzW
ijyj}gpWha
} F\Tlpp9
H+*o @0C\~
T*A_F
[
wW!*"z
0 w@~ynW[
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 -*?a*q/#nQ
,$}v_-:[l
询,接下来编写UserDAO的代码: $lV0TCgba8
3. UserDAO 和 UserDAOImpl: \>,{)j q;
java代码: <=19KSGFt
\Sm.]=br
[lyB@) 6.
/*Created on 2005-7-15*/ <V>vDno\
package com.adt.dao; tYmWze.j
S~Nx;sB
import java.util.List; C7q bofoV
of{wZU\J+9
import org.flyware.util.page.Page; 8?I(wn
Q&n
import net.sf.hibernate.HibernateException; `'
6]Z*
E$8GXo00v
/** gDAA>U3|$
* @author Joa
].:S!QO
*/ (M5=8g%>d
publicinterface UserDAO extends BaseDAO { >@TZYdl
!>t|vgW
publicList getUserByName(String name)throws rJ!xzge;G
UXIq>[2Z1
HibernateException; .F
3v)
2v%~KV
publicint getUserCount()throws HibernateException; GHYgSS
hiP^*5h
publicList getUserByPage(Page page)throws N],A&}30
O \lt!p3F
HibernateException; q[dls_
chfj|Ce]x
} $ n
7dIE
$i~DUT(
Pf@8C{I
k[G? 22t
Cww$ A %}
java代码: _W?}%;
oN)K2&M0
:X2B+}6_&
/*Created on 2005-7-15*/ c&F"tLl
package com.adt.dao.impl; >@y5R^B`
>`s2s@Mx
import java.util.List; A")B<BK
$&lS7}
import org.flyware.util.page.Page; y4M<L. RO
H>_%ZXL
import net.sf.hibernate.HibernateException; YSv\T '3
import net.sf.hibernate.Query; bU_9GGG|
HjV83S;
import com.adt.dao.UserDAO; :K2N7?shA
Q1s`d?P/`
/** &t%ICz&3
* @author Joa JH<q7Y6!y
*/ Ybd){Je"z
public class UserDAOImpl extends BaseDAOHibernateImpl *"1]NAz+
j.ANBE96>
implements UserDAO { 3haY{CEr
D97oS!*
/* (non-Javadoc) SDdK5@1O4o
* @see com.adt.dao.UserDAO#getUserByName ?c=l"\^x
f]o DZO%^
(java.lang.String) 9e8@0?0
*/ oa;[[2c
publicList getUserByName(String name)throws wf8vKl#Kfw
1Qf5H!5vx
HibernateException { Mgf80r=
String querySentence = "FROM user in class &)\0mpLK9
JJ7-$h'0q
com.adt.po.User WHERE user.name=:name"; <\Y>y+$3
Query query = getSession().createQuery m6'YFpf)V
!|Vjv}UO
(querySentence); u%h]k ,(E
query.setParameter("name", name); p?8>9
return query.list(); :
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GG
} 1Pn!{ bU3@
;~/
/* (non-Javadoc) o+6Y/6Xp@
* @see com.adt.dao.UserDAO#getUserCount() 1VJE+3
*/ ,n&Dg58K
publicint getUserCount()throws HibernateException { G7zfyw}W
int count = 0; }$g5:k!
String querySentence = "SELECT count(*) FROM ?^,GaZ^V
<}i\fJX6
user in class com.adt.po.User"; ng<|lsZd
Query query = getSession().createQuery gEPCXf
uOm fpg O
(querySentence); c;(}Ih(#
count = ((Integer)query.iterate().next ;k!Ej-(
rQ~%SUM7
()).intValue(); 63F0Za}h
return count; \n+`~< i
} B>9D@fmzs
bjD0y
cB[
/* (non-Javadoc) Xo]FOJ5
* @see com.adt.dao.UserDAO#getUserByPage H(n_g
QAX
7J0PO}N
(org.flyware.util.page.Page) Yxi.A$g
*/ <0&];5
on
publicList getUserByPage(Page page)throws _K/h/!\n
@R`OAdy
HibernateException { i,b>&V/Y$
String querySentence = "FROM user in class #(XP=PUj
3MkF
com.adt.po.User"; ?i9LqHL
Query query = getSession().createQuery Lqwc:%Y:_
g($ y4~#
(querySentence); N2q'$o
query.setFirstResult(page.getBeginIndex()) ~-'nEA TE
.setMaxResults(page.getEveryPage()); aD%")eP%&
return query.list(); X0P<ifIv
} Pm"
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L;grH5K5
} Pf(z0o&
5 _] i==M
7j._3'M=Kc
K$f~Fft
ob-be2EysH
至此,一个完整的分页程序完成。前台的只需要调用 O%
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97<Y.
0
userManager.listUser(page)即可得到一个Page对象和结果集对象 w[]7{D];
+O\6p
的综合体,而传入的参数page对象则可以由前台传入,如果用 1gCp/m2r7
l_QpPo!a
webwork,甚至可以直接在配置文件中指定。 |bB..b
b\6w[52m
下面给出一个webwork调用示例: MUVp8!*@
java代码: s}/YcUK
OG}0{?
zXp{9P\c
/*Created on 2005-6-17*/ 8 I,(\<Xv
package com.adt.action.user; "64pVaT4
<R_3;5J%
import java.util.List; e$Md?Pq
H|75, !<
import org.apache.commons.logging.Log; u9k##a4.E
import org.apache.commons.logging.LogFactory; QeU>%qKT
import org.flyware.util.page.Page; BA
L!6
W\FKAvS
import com.adt.bo.Result; WS2TOAya)
import com.adt.service.UserService; g[:5@fI#*
import com.opensymphony.xwork.Action; a Se.]_
vmW4a3
/** d+"KXt5CV
* @author Joa fZXd<Fg+
*/ [=.. #y!U
publicclass ListUser implementsAction{ N[r@Y{
ygT,I+7\
privatestaticfinal Log logger = LogFactory.getLog rP#@*{";
/C3=-Hp
(ListUser.class); &/Tx@j^.C
= `70]%
private UserService userService; 85Ms*[g
Y@;bA=Du}
private Page page; /kNr5s
vC+mC4~/(
privateList users; Q7`zrCh
.8fOc.h8h
/* W6~<7
* (non-Javadoc) v)rN]b]
* +h*&r~T
* @see com.opensymphony.xwork.Action#execute() RC\TPG/8!
*/ ib uA~\5
publicString execute()throwsException{ +ZGOv,l
Result result = userService.listUser(page); NE3G!qxL
page = result.getPage(); +.[#C5
users = result.getContent(); gy~M]u{
return SUCCESS; 5M*q{kX)
} ZhM-F0;`
o<T>G{XYB
/** dI'C[.zp[
* @return Returns the page. 'Y>!xm
*/ u4fTC})4{C
public Page getPage(){ vjbot^W9
return page; 6U# C
} 5C{X$7u
r|rV1<d
/** QT^(
oog=
* @return Returns the users. I]ywO4
*/ E39:}_IV
publicList getUsers(){ >-+MWu=
return users; lL%7lO
} ?mgr#UN
kZF\V7k
/** {TUCa
* @param page {`l]RIig
* The page to set. IcaIB)
*/ qY#*zx
publicvoid setPage(Page page){ c|ZZ+2IYd
this.page = page; _VR4|)1g
} XTHrf'BU
'KyT]OObS
/** |oO0%#1H
* @param users bu@Pxz%_
* The users to set. *GD 1[:
*/ nc@ul')
publicvoid setUsers(List users){ x-Xb4?{
this.users = users; 2Uu,Vv
} "B)DX*-\?
C|z`hNp
/** ~oSLWA9
* @param userService c.jnPVf:
* The userService to set. _FAwW<S4B
*/ T /[)U
publicvoid setUserService(UserService userService){ B(b[Dbb
this.userService = userService; FKL}6W:
} M(oW;^B
} <2|x]b8
5Ko"-
9DPf2`*$
ls#O0
'[Nu;(>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, .%~
L
&QCqaJ-
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 V 9=y@`;
{SK8Mdn
么只需要: 5dYIL`
java代码: &+%CC
Z<ke!H
oJXZ}>>iT
<?xml version="1.0"?> tDIzn`$z
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork B-M|}T
hhYo9jTHW
1.0//EN" "http://www.opensymphony.com/xwork/xwork- |a^ydwb
i?*&1i@
1.0.dtd"> h1)p{5}H
1F[;
)@
<xwork>
{n.g7S~
MZL~IX
<package name="user" extends="webwork- /[{?zS{
Td8'z'
interceptors"> <-FZ-asem
T5Pc2R
<!-- The default interceptor stack name ?&/9b)c S
G-,PsXSwe
--> :5@7z9 >
<default-interceptor-ref p'xj:bB
VFG)|Z
name="myDefaultWebStack"/> .@=d I
:i:Zc~%
<action name="listUser" wl(}F^:/`
RZ?>>Ll6
class="com.adt.action.user.ListUser"> ?8vjHEE
<param _>3GNvS
!kmo%+
name="page.everyPage">10</param> (v(_XlMK
<result `bt]v $
frGUT#9?n
name="success">/user/user_list.jsp</result> (S9"(\A
</action> O7rm(
q{KRM\ooYs
</package> _L# Tp
Blaj07K
</xwork> gdkO|x
hA/FK
8U\ +b?}
ncS^NH(&
rEddX
S93NsrBbY
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 5HOhk"
;5 IS58L
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。 X>*zA?:
G. <9K9K
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 C'zMOR6c
`=CF
|I
-U;s,>\)
KZD&Ih(vC
tK8\Ib J
我写的一个用于分页的类,用了泛型了,hoho E}"&?oY
%M'"%Yn@(y
java代码: hi.{
;B1}so1]
lkw[Z}\
package com.intokr.util; M_*w)<
e@F&/c
import java.util.List; yChC&kX
Z+
q:?g?v
/** 0imz}Z]
* 用于分页的类<br> uy`U1>
* 可以用于传递查询的结果也可以用于传送查询的参数<br> S6]D;c8GE
* 's&Vg09D,
* @version 0.01 '*)!&4f
* @author cheng U?>zq!C&R
*/ ;#f%vs>Y7i
public class Paginator<E> { faMUd#o&
privateint count = 0; // 总记录数 *23
privateint p = 1; // 页编号 q)@.f.
privateint num = 20; // 每页的记录数 O`@$YXuD
privateList<E> results = null; // 结果 EDnmYaa)dZ
!)LR41>?
/** WpmypkJA#
* 结果总数 ;q$<]X_S)}
*/ 6] <?+#uQ
publicint getCount(){ J'B;
return count; I
s8|
} \&e+f#!u
^g~-$ t<!
publicvoid setCount(int count){ M{nz~W80
this.count = count; UejG$JyHP
} B]]M?pS
=Oo*7|Z
/** JaIj9KLNX
* 本结果所在的页码,从1开始 -u8@ .
* OgOu$.
* @return Returns the pageNo. qqkZbsN
*/ 9Ft)VX
publicint getP(){ ;M'R/JlUN
return p; kWoy%?|RRa
} />f`X+d
^2=Jv.2{|
/** mTs[3opg
* if(p<=0) p=1 ^[id8
* 4|XE
f,
* @param p )<3WVvB
*/ 3>S.wyMR4
publicvoid setP(int p){ -Mv`|odY/
if(p <= 0) x80~j(uVf
p = 1; B}?/oZW4
this.p = p; &/7GhZRt
} k+s<;{
Mq*Sp
UR
/** } [75`pC~O
* 每页记录数量 c)Y I3G$
*/ b!`:|!7r'
publicint getNum(){ 'fg`td
return num; ~xHr/:
} w$&10
y XS/3_A{
/** if`/LJsa
* if(num<1) num=1 :$94y{
*/ nQ/ha9v=n
publicvoid setNum(int num){ kB~: HQf
if(num < 1) XPY66VC&_
num = 1; G1P m!CM=
this.num = num; k@wT,?kD
} 9Y/c<gbY
HVk3F|]V
/** :b.#h7Qt<
* 获得总页数 <p<gx*%
*/ z?yADYr9
publicint getPageNum(){ $'&`k,a3|P
return(count - 1) / num + 1; bBDgyFSI<
} u' r;-|7
H5qa7JMZ
/** _
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* 获得本页的开始编号,为 (p-1)*num+1 IWMqmCbv
*/ 6.By)L
publicint getStart(){ @<w$QD
return(p - 1) * num + 1; V;)'FJ)]
} ,q:6[~n
: ;d&m
/** #s]]\
* @return Returns the results. #}B~V3UD
*/ Yq2mVo
publicList<E> getResults(){ XKR?vr7A2
return results; jh=:Q P/
} }K&K{ 9}
;Y)?6^"
public void setResults(List<E> results){ Z4t9q`}h
this.results = results; ^ S%4R'
} p?dMa_g
v#nFPB=z
public String toString(){ [u-~<80
StringBuilder buff = new StringBuilder g0ug:- R
o}NKqA3
(); ;vd%=vR
buff.append("{"); @9QHv
buff.append("count:").append(count); 0<o#;ZQ]
buff.append(",p:").append(p); 1`h`-dqr#
buff.append(",nump:").append(num); OCRx|
buff.append(",results:").append S"}FsS;k<?
vK$T$SL
(results); ;f6G&>p
buff.append("}"); 38 B\ \
return buff.toString(); F1/f:<}
} Oz n7C?\*
:v&GAs6H
} _b#9^2o
FiIN\
(zTr/