Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ]h=y
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 `;Fs
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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 dr"@2=Z
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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 VhgcvS@V
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。 0|rdI,z
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分页支持类: ,;=is.h9
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java代码: BJZGQrsz
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#
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package com.javaeye.common.util; gF~
}
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import java.util.List; C*Y0GfW=
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publicclass PaginationSupport { cyI:dvg
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publicfinalstaticint PAGESIZE = 30; n4AQ
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privateint pageSize = PAGESIZE; vb\R~%@T,
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privateList items; ~?lmkfy
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privateint totalCount; !8J%%Ux&M
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privateint[] indexes = newint[0]; MWn[]'TpH
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privateint startIndex = 0; ?d)eri8,
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public PaginationSupport(List items, int ?)/H8n
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totalCount){ }M(XHw
setPageSize(PAGESIZE); _^w^tfH]
setTotalCount(totalCount); zhACNz4tJ
setItems(items); 7(zY:9|(
setStartIndex(0); SciEHI#
} ]=5D98B
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public PaginationSupport(List items, int g\?7M1~
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totalCount, int startIndex){ I9jzR~T
setPageSize(PAGESIZE); Z&y9m@
setTotalCount(totalCount); /}-LaiS
setItems(items); Y&*nj`n
setStartIndex(startIndex); `H|#l\
} _
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public PaginationSupport(List items, int % wh>_Ho
`S/;S<';
totalCount, int pageSize, int startIndex){ a#P{ [
setPageSize(pageSize); r1xhplHH@
setTotalCount(totalCount); -;[,`g(f
setItems(items); -<n]Sv;V
setStartIndex(startIndex); AkV8}>G?#A
} Y/n],(t)
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publicList getItems(){ =MMSmu5!
return items; <o_(,,P%
} j1P#({z[
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publicvoid setItems(List items){ Gn?<~8a
this.items = items; z_ia3k<
} >z69r0)>
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publicint getPageSize(){ 5!d'RBO
return pageSize; oOy_2fwZPp
} G9a6 $K)b
{rZ )!
publicvoid setPageSize(int pageSize){ JXF@b-c
this.pageSize = pageSize; ^eWD4Vp|4
} K<ok1g'0
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publicint getTotalCount(){ 3R$*G8v
return totalCount; xw&N[y5
} {vAv ;m
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publicvoid setTotalCount(int totalCount){ dht*1i3v
if(totalCount > 0){ g%f6D%d)A
this.totalCount = totalCount; ioS(;2F
int count = totalCount / RE75TqYW
[>U =P`
pageSize; NYp46;
if(totalCount % pageSize > 0) zvnR'\A_
count++; .uu[MzMIu
indexes = newint[count]; XSz)$9~hk
for(int i = 0; i < count; i++){ -85W/%
indexes = pageSize * xsdi\
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i; qFYM2
} ju?D=n@i
}else{ G^/8lIj
this.totalCount = 0; Mi&jl_&
} TbA=bkj[4
} \ POQeZ
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publicint[] getIndexes(){ _V-pr#lP1
return indexes; DS1_hbk
} nf9NJ_8}4H
16R0#Q/{+*
publicvoid setIndexes(int[] indexes){ V'&`JZK6
this.indexes = indexes; ww$Ec
} ^5BQ=
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publicint getStartIndex(){ h1.<\GO
return startIndex; #=\ nuT'oy
} /#I~iYPe
uiIS4S_
publicvoid setStartIndex(int startIndex){ 80;^]l
if(totalCount <= 0) lcYjwA
this.startIndex = 0; ae|j#!~oi
elseif(startIndex >= totalCount) K/ 5U;oC
this.startIndex = indexes 6E@qZvQ
&a
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[indexes.length - 1]; VgyY7INx9
elseif(startIndex < 0) _Kf8,|+
this.startIndex = 0; v)J(@>CZ[
else{ \t^h|<`
this.startIndex = indexes ~V6wcXd
n(tx'&U"R
[startIndex / pageSize]; L:E?tR}H
} >crFIkOJ
} _/`H<@B_U
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publicint getNextIndex(){ UCVdR<<Z
int nextIndex = getStartIndex() + ==)q{e5
Yb;$z'
pageSize; XdxSi"+
if(nextIndex >= totalCount) 3r-oZ8/n
return getStartIndex(); $;%k:&\f
else Th>ff)~e
return nextIndex; G"|`&r@
} lLi)?
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publicint getPreviousIndex(){ S{#L7S
int previousIndex = getStartIndex() - K]c\3[vR
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pageSize; dcbE<W#ss
if(previousIndex < 0) &Y3r'"
return0; OT{cP3;0*o
else !ZrU@T
return previousIndex; RJk4 2;]
} !b 4v}70,
!$L~/<&0g
} 5l[&-:(Lh
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mfCp@1;26
{q1u[T&r
抽象业务类 ^R7|x+
java代码: ^9fY%98
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/** -fCR^`UOS
* Created on 2005-7-12 ^e\H V4s
*/ )
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package com.javaeye.common.business; g`\5!R1
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import java.io.Serializable; R;3nL[{U
import java.util.List; ^bG91"0A
!@3"vd{^
import org.hibernate.Criteria; 5-?*Boi>i
import org.hibernate.HibernateException; My<.^~
import org.hibernate.Session; 2D)B%nM[
import org.hibernate.criterion.DetachedCriteria; 'B yB1NL
import org.hibernate.criterion.Projections; #bCQEhCy
import 1=z6m7@'-
4U>g0
org.springframework.orm.hibernate3.HibernateCallback; :Fh#"<A&&
import l#bE_PD;
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org.springframework.orm.hibernate3.support.HibernateDaoS +*L<"@
k$3Iv"gbx
upport; dwJnPJ=z
</]a`h]
import com.javaeye.common.util.PaginationSupport; #sM`>KG6T1
uF<}zFS
public abstract class AbstractManager extends x@#aOf4<U
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HibernateDaoSupport { as3*49^9
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privateboolean cacheQueries = false; jG["#5<?
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privateString queryCacheRegion; i[/`9 AK
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publicvoid setCacheQueries(boolean 2$TwD*[
8h,=yAn5
cacheQueries){ .s-*aoj
this.cacheQueries = cacheQueries; vR4omB{
} 7!/!a*zg
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publicvoid setQueryCacheRegion(String F[KM0t!
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queryCacheRegion){ bJoP@s
this.queryCacheRegion = +$$5Cv5#<&
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queryCacheRegion; ~@mNR^W-W
} ^C'{# p"
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publicvoid save(finalObject entity){ Y^tUcBm\
getHibernateTemplate().save(entity); ;a 6Z=LB
} [*U.bRs
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publicvoid persist(finalObject entity){ =$SvKzN
getHibernateTemplate().save(entity); sA2esA@C<o
} . ZP$,
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publicvoid update(finalObject entity){ bT15jNa
getHibernateTemplate().update(entity); u0F{.fe
} MO%+rf0~w
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publicvoid delete(finalObject entity){ mO2u9?N
getHibernateTemplate().delete(entity); _%G;^ b
}
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publicObject load(finalClass entity, y({lE3P
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finalSerializable id){ [<WoXS1LX
return getHibernateTemplate().load dkg|
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(entity, id); L~Y^O`c
} jo'
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publicObject get(finalClass entity, Je4hQJ<h
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finalSerializable id){ :. u2^*<
return getHibernateTemplate().get G=er0(7<
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(entity, id); KAgxIz!^-1
} |$g} &P8;
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publicList findAll(finalClass entity){ ?[;>1+D
return getHibernateTemplate().find("from De2$:?
w=FU:q/
" + entity.getName()); o)n=n!A
} 0#CmB4!<O
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publicList findByNamedQuery(finalString $WXO1o(O
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namedQuery){ 2!R+5^Iy
return getHibernateTemplate 2~R%_r+<
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().findByNamedQuery(namedQuery); wjXv{EsMq
} 3L36
2
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publicList findByNamedQuery(finalString query, B=~uJUr
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finalObject parameter){ 0g9y4z{H
return getHibernateTemplate zkquXzlgB
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().findByNamedQuery(query, parameter); ~n$\[rQ
} Ehxu`>@N
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publicList findByNamedQuery(finalString query, p3>Md?e
Tp|>(~;ai
finalObject[] parameters){ Y]7 6y>|e
return getHibernateTemplate 9N<=,!;5~s
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().findByNamedQuery(query, parameters); ^B1$|C
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} >pp#>{}
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publicList find(finalString query){ Z/T(4
return getHibernateTemplate().find tSe[*V4{'
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(query); yb,X
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} #lO ^PK
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publicList find(finalString query, finalObject A/{!w"G
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parameter){ /P Tq.
return getHibernateTemplate().find vqZBDQ0
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(query, parameter); q0DRT4K
} {$#88Qa\-
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public PaginationSupport findPageByCriteria [] el4.J,
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(final DetachedCriteria detachedCriteria){ ?C- ju8]|
return findPageByCriteria m>RtKCtP
`X)A$lLr
(detachedCriteria, PaginationSupport.PAGESIZE, 0); {T-^xwc
} 1 e]D=2y
GaV} @Q
public PaginationSupport findPageByCriteria hxMV?\MYj
&;~?\>?I
(final DetachedCriteria detachedCriteria, finalint YrYmPSb=
7dv!
startIndex){ 3 NFo=Z8
return findPageByCriteria y` {|D*
s4QCun~m
(detachedCriteria, PaginationSupport.PAGESIZE, )%PMDG|
+prUau*
startIndex); ns*:mGh
} _8!x
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public PaginationSupport findPageByCriteria 3y,2RernK
slhMvHOk-
(final DetachedCriteria detachedCriteria, finalint ~KV{m
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pageSize, q6 ny2;/r
finalint startIndex){ Zd88+GS,#
return(PaginationSupport) #kh:GAp]
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getHibernateTemplate().execute(new HibernateCallback(){ |f/Uzd ~
publicObject doInHibernate VN(*m(b
t{QQ;'
(Session session)throws HibernateException { {9X mFa
Criteria criteria = vCNq2l^CW
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detachedCriteria.getExecutableCriteria(session); ;xiwyfqgE
int totalCount = axDa&7%
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((Integer) criteria.setProjection(Projections.rowCount ~)n[Vf
<*WGvCh%w
()).uniqueResult()).intValue(); *X{7m]5
criteria.setProjection IsShAi
8};kNW^2m
(null); KVr9kcs
List items = Gz BPI'C
l~w^I|M^C
criteria.setFirstResult(startIndex).setMaxResults seRf q&
/.=aA~|
(pageSize).list(); @56*r@4:q
PaginationSupport ps = 6yO5{._M
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new PaginationSupport(items, totalCount, pageSize, .6LRg
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startIndex); >MSK.SNh
return ps; >*opE I+
} Qc)i?Z'6
}, true); Dy>6L79G
} p*)I QM<B
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public List findAllByCriteria(final TUz4-Pd
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DetachedCriteria detachedCriteria){ r>7+&s*yk
return(List) getHibernateTemplate ^y qRa&
Aj=GekX{
().execute(new HibernateCallback(){ !h|,wq]k
publicObject doInHibernate ,Q3OQ[Nmh
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(Session session)throws HibernateException { x0jaTlU/
Criteria criteria = !icI Rqcf=
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detachedCriteria.getExecutableCriteria(session); s^SU6P/]
return criteria.list(); "(vK.-T
} ^1vKhO+p$
}, true); 2~l7WW+lx,
} F_9
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public int getCountByCriteria(final PH%'^YAl7
# ACT&J
DetachedCriteria detachedCriteria){ Rd5-ao4
Integer count = (Integer) EI7n|X
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@
getHibernateTemplate().execute(new HibernateCallback(){ p5tb=Zg_
publicObject doInHibernate (QL:7
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(Session session)throws HibernateException { 'S9o!hb'@
Criteria criteria = f6yj\qq]
]s\vc:cc?
detachedCriteria.getExecutableCriteria(session); c61OT@dZEA
return `/`iLso&-
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criteria.setProjection(Projections.rowCount ^<-)rzTI
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()).uniqueResult(); 6W{Nw<
} +Ugy=678Tr
}, true); >
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return count.intValue(); leb/D>y
} !=PH5jTY
} @TD=or .&
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用户在web层构造查询条件detachedCriteria,和可选的 D!!
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 2>o^@4PnZ
]u!s-=3s
PaginationSupport的实例ps。 ybqmPT'|_
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ps.getItems()得到已分页好的结果集 x {Utf$|
ps.getIndexes()得到分页索引的数组 *?d\Zcj85[
ps.getTotalCount()得到总结果数 O8b#'f~
ps.getStartIndex()当前分页索引 ^)Awjj9
ps.getNextIndex()下一页索引 M>Tg$^lm
ps.getPreviousIndex()上一页索引
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ~!~i_L\V
ga/zt-&
,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 .Z'NH
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h)ZqZ'k$
一下代码重构了。 }|2A6^FH.
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我把原本我的做法也提供出来供大家讨论吧: ^.iRU'{
KYw7Jx`l
首先,为了实现分页查询,我封装了一个Page类: 9xz@2b@
java代码: Um\HX6
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/*Created on 2005-4-14*/ zps=~|
package org.flyware.util.page; r>ed/<_>m;
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/** 7F0J*M
* @author Joa XXn3K BIf
* xtD(tiqh.;
*/ T=u"y;&L
publicclass Page { p *42
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}(!Uq
/** imply if the page has previous page */ HQ9tvSc
privateboolean hasPrePage; 2"Wq=qy\J
gAorb\iJ
/** imply if the page has next page */ Z;a)P.l.>
privateboolean hasNextPage; F7O*%y.';
4]m{^z`1
/** the number of every page */ dWkQ NFKF
privateint everyPage; 'A.5T%n-
e,p*R?Y{[
/** the total page number */ [(_,\:L${
privateint totalPage; ,)*[Xa_n
)uOtQ0
/** the number of current page */ #GlFm?/6K/
privateint currentPage; +em!TO
B-]bhA4|:
/** the begin index of the records by the current Mz(?_7
zEO~mJzo
query */ '+{yg+#/wV
privateint beginIndex; yp$jLBA
-hW>1s<
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/** The default constructor */ "Hz%0zP&
public Page(){ kP[fhOpn
}"WovU{*s
} (_ :82@c
Zl&ED{k<
/** construct the page by everyPage 2;"vF9WMm
* @param everyPage )e'F[
* */ #z&R9$
public Page(int everyPage){ 6M7GPHah
this.everyPage = everyPage; TA/hj>rV
} ~ !mY0odH
j0+D99{R
/** The whole constructor */ }%?or_f/
public Page(boolean hasPrePage, boolean hasNextPage, o96c`a u
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@]#[TbNo
int everyPage, int totalPage, 0aY\(@
int currentPage, int beginIndex){ IFew3!{\
this.hasPrePage = hasPrePage; qF$y
p>|#
this.hasNextPage = hasNextPage; $$.q6
this.everyPage = everyPage; ,.(:b82$
this.totalPage = totalPage; 5lD`qY
this.currentPage = currentPage; YHom9&A
this.beginIndex = beginIndex; }]dzY(
} 1+-Go}I
Kgi`@`
/** 7J5jf231
* @return eDP&W$s#
* Returns the beginIndex. 12'MzIsU's
*/ kG5+kwV=:
publicint getBeginIndex(){ o:ow"cOEf
return beginIndex; u? >x
} Q.eD:@%iE
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,
/** >gL&a#<S
* @param beginIndex n_]B5U
* The beginIndex to set. qvo!nr7
*/ HxW/t7Z(
publicvoid setBeginIndex(int beginIndex){ l
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this.beginIndex = beginIndex; RAu(FJ
} '[8w8,v(
@<$m`^H
/** v)O].Hd
* @return b49h @G
* Returns the currentPage. n(# yGzq
*/ YU6|/
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publicint getCurrentPage(){ `u_MdB}<x;
return currentPage; &F#eYEuy
} &E0^Jz
+RM!j9Rq
/** MHt
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* @param currentPage $v2t6wS,"
* The currentPage to set. jf1GYwuW*
*/ PE6,9i0ee
publicvoid setCurrentPage(int currentPage){ /^jl||'H,:
this.currentPage = currentPage; :oW 16m1`
} EX!`Zejf
xbw;s}B
/** u@:[ dbJ
* @return K@2"n|
S;
* Returns the everyPage. Z-4/xi7
*/ zmD7]?|
publicint getEveryPage(){ t+F_/_"B
return everyPage; ?MSwr_eZH
} seAPVzWUU
NQuqM`LSQ
/** `_1fa7,z
* @param everyPage ?RsPAL
* The everyPage to set. x\ #K2
*/ p>J@"?%^
publicvoid setEveryPage(int everyPage){ l44QB8
9
this.everyPage = everyPage; 6A=k;do
} xH`
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N$t<&5+
/** pN9U1!|uam
* @return LcA7f'GVK
* Returns the hasNextPage. *PFQ
*/ c+z [4"rYL
publicboolean getHasNextPage(){ Nc[N 11?O
return hasNextPage; t OJyj49^a
} GNuIcy
j-"34
/** +Tx_q1/f5X
* @param hasNextPage N8kNi4$mp=
* The hasNextPage to set. V'dw=W17V
*/ m##!sF^k~J
publicvoid setHasNextPage(boolean hasNextPage){ KrG,T5
this.hasNextPage = hasNextPage; NhTJB7
} >iG3!Td)y
HrZX~JnTmf
/** :|ahu
* @return 6XCFL-o-
* Returns the hasPrePage. Ja&S_'P[
*/ &M3KJ I0L
publicboolean getHasPrePage(){ GB}=
return hasPrePage; dP_bFU zg
} W?wt$'
\I}EWI
/** {fV$\^c
* @param hasPrePage %#&njP
* The hasPrePage to set. 4:**d[|1
*/ >)diXe}j
publicvoid setHasPrePage(boolean hasPrePage){ P {n*X
this.hasPrePage = hasPrePage; W{Z7=
} 2)0J@r'
1k)pJzsc
/** bd}[X'4d
* @return Returns the totalPage. :HrFbq
* Svo\+S
*/ 6yAZvX
publicint getTotalPage(){ !kb:g]X
return totalPage; [.Fq
l+
} [7r^fD
A
/uR/,R++
/** Bvj sl
* @param totalPage Eld[z{n"
* The totalPage to set. l.g.O>1
*/ ~9#x=nU:+V
publicvoid setTotalPage(int totalPage){ `s
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this.totalPage = totalPage; HIE8@Rv/3
} a(?)r[=
9MI9$s2y
} Z'!ORn#M
{{M/=WqC
E6O!e<ze^
W4k$m2
s>\^dtG7
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 GBpdj}2=
n=$ne2/
个PageUtil,负责对Page对象进行构造: *ej< 0I{
java代码: KDGrX[L:6
+|X`cmnuU
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/*Created on 2005-4-14*/ [dFcxzM-N
package org.flyware.util.page; |sFd5X
@+p(%
import org.apache.commons.logging.Log;
f.aa@>
import org.apache.commons.logging.LogFactory; {29aNm
dy5}Jn%L
/** kn$_X4^?
* @author Joa HRM-r~2:-]
* m`q&[:
*/ ewdTsgt'
publicclass PageUtil { L%\Wt1\[
52#6uBe
privatestaticfinal Log logger = LogFactory.getLog m2l9([u=^
)wD/<7;
(PageUtil.class); _
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%
_Ds,91<muQ
/** y`7<c5zD
* Use the origin page to create a new page Kj3Gm>B<y
* @param page Ac|dmu
* @param totalRecords %t!S 7UD
* @return .o C!~'
*/ YtWw)IK
publicstatic Page createPage(Page page, int TKAs@X,t
^^B_z|;Aa
totalRecords){ Y[R>?w
return createPage(page.getEveryPage(), OyK#Rm2A=
eu_ZsseZ
page.getCurrentPage(), totalRecords); -+Yark
} {~Jk (c~I
F$'u`
/** $Q'z9ghEg
* the basic page utils not including exception RU6c 8>"
sb8bCEm-\
handler #wRhR>6
* @param everyPage _TsN%)m
* @param currentPage 1t?OD_d!8
* @param totalRecords A9K$:mL<2
* @return page ]a~sJz!
*/ n@;B_Bt7
publicstatic Page createPage(int everyPage, int E7@Gpu,o
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currentPage, int totalRecords){ :@-yK8q's
everyPage = getEveryPage(everyPage); !P^Mo> "
currentPage = getCurrentPage(currentPage); @sg.0GR
int beginIndex = getBeginIndex(everyPage, +5Dc5Bl
Y0EX{oxt1
currentPage); rrj.]^E_~
int totalPage = getTotalPage(everyPage, 3Os0<1@H
Y(kf<Wo
totalRecords); >.K%W*t
boolean hasNextPage = hasNextPage(currentPage, P\6:euI
a9{NAyl<oo
totalPage); V!^0E.?a
boolean hasPrePage = hasPrePage(currentPage); oxL<\4)WJ
dc1Zh
W4
returnnew Page(hasPrePage, hasNextPage, g<0K
i^#
everyPage, totalPage, BQg3+w:>
currentPage, &V(6N%A^U
vS0 ii
beginIndex); !-3;Qj}V
} Y\B6c^E)
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privatestaticint getEveryPage(int everyPage){ il!B={
return everyPage == 0 ? 10 : everyPage; N_iy4W(NU
} 5<v1v&
^5TVm>F@3
privatestaticint getCurrentPage(int currentPage){ 6<fG;:
return currentPage == 0 ? 1 : currentPage; ivq(eKy
} 6z6\xkr
pXN'vP
privatestaticint getBeginIndex(int everyPage, int #(Gz?kGAH`
*xsBFCRU
currentPage){ p!uB8F
return(currentPage - 1) * everyPage; ]|,}hsN
} rEj[XK
)qbkKCq/FB
privatestaticint getTotalPage(int everyPage, int ~v pIy -
Z/?{{}H+
totalRecords){ \({'Xo >(
int totalPage = 0; U1)Zh-aR
OM\1TD/-
if(totalRecords % everyPage == 0) S-gO
totalPage = totalRecords / everyPage; {dpDQP +!
else sHk>ek]2I
totalPage = totalRecords / everyPage + 1 ; a4 N f\7
>|kD(}Axf
return totalPage; 1eshuL
} w@cW`PlF
]2)A/fOW
privatestaticboolean hasPrePage(int currentPage){ oU\7%gQ
return currentPage == 1 ? false : true; \DZ.#=d
} ug2W{D
jLVD37 P^
privatestaticboolean hasNextPage(int currentPage, *OFG3 uM
H#;*kc
a4
int totalPage){ =tt3nfZ9
return currentPage == totalPage || totalPage == %ZWt 45A
C2v_],]
0 ? false : true; ={oNY.(Q
}
Fl=H5HR
-~~h1
d:K\W[$Bz
} 0,ryy,2
~d]v{<3
Y&O2;q/B
Jk\-e`eE
pIcg+~
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 9_:"`)]3B
;Hk3y+&]a
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 >iOf3I-ATt
NC-K`)
做法如下: Vl5>o$G|<.
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 H"AL@=
BK%B[f*[OA
的信息,和一个结果集List: L@(. i
java代码: [%dsq`b#
<5z!0m-G
NLL"~
/*Created on 2005-6-13*/ 2'S&%UyP
package com.adt.bo; aH_c84DS
v~L\[&|_
import java.util.List; @s-P!uCaT
;Y*K!iFWH
import org.flyware.util.page.Page; X<;.
p)/e;q^
/** gE\ ^ vaB
* @author Joa jerU[3
*/ N
{
oVz],
publicclass Result { IVSC7SBiT
T/P\j0hR
private Page page; q\o#<'F1J
AEyD?^?
private List content; x7zc3%T's
]z^jz#>um&
/** cl^UFlf[
* The default constructor u5}:[4N%I
*/ ]ouoRlb/
public Result(){ u$a K19K/
super(); La1:WYt
} |cY HH$
%;:![?M
/** .2JZ7
* The constructor using fields }NC$Ce
* ESV./~K
* @param page ,nteIR'??
* @param content u?72]?SM
*/ K _VIk'RB
public Result(Page page, List content){ ^R@)CIQ
this.page = page; 5 [~HL_u;,
this.content = content; (]'wQ4iQ
} tB>!1}v
z]8Mv(eL
/** s|<n7 =J
* @return Returns the content. ^aAs=KditO
*/ {"Sv~L|J;
publicList getContent(){ \UK}B
return content; 5\quh2Q_
} Ro2V-6/
PM84Z@Y
/** Jl\xE`-7
* @return Returns the page. X2Ak
*/ Fw&ImRMk
public Page getPage(){ PdO"e
return page; qA7,txQ:
} L%v@|COQ3
]j7`3%4uK
/** qLLrR,:
* @param content <Y"RsW9
* The content to set. F(`|-E"E;
*/ np^&cY]
public void setContent(List content){ b_ZvI\H
this.content = content; a.%ps:
} R&W%E%uj
bDWLHdu
a
/** 6Z#Nh@!+C
* @param page 30^q_|l:]
* The page to set. O.Pp*sQ^
*/ ++,I`x+p
publicvoid setPage(Page page){ A` _dj}UF
this.page = page; 6t; ;Fz
} q("XS
} $5 G(_
Iz+%wAZ|B6
O/#3QK
9~~NxWY%x
MS""-zn<
2. 编写业务逻辑接口,并实现它(UserManager, !8UIyw
+C!GV.q[
UserManagerImpl) QYo04`Rl
java代码: :&
Dv!z
kfas4mkc
*.nSv@F
/*Created on 2005-7-15*/ aWTurnee^
package com.adt.service;
ZJs~,Q
D1y`J&A>Q
import net.sf.hibernate.HibernateException; -hnNaA
G)s.~ T
import org.flyware.util.page.Page; ri4z^1\
"|(.W3f1
import com.adt.bo.Result; IWv5UmjN
#w|v.35%?
/** eowwN>-2C
* @author Joa Tfh2>
*/ /A0_#g:2*#
publicinterface UserManager { iqB5h|
`
feyc
public Result listUser(Page page)throws o
A2oX
)e0kr46
HibernateException; P@UE.0NYX
~ `}),aA
} <MJU:m$3
vai w*?jV
5T.U=_ag
$>#0RzU
u4FD}nV
java代码: 6ZE`'pk<
=At" Q6-O
%R?7u'=~
/*Created on 2005-7-15*/ QErdjjgE
package com.adt.service.impl; \9`E17i
V.
i{IW
import java.util.List; &X:;B'
=M-=94
import net.sf.hibernate.HibernateException; F&!vtlV)
]CLM'$
import org.flyware.util.page.Page; DQK?y=vf
import org.flyware.util.page.PageUtil; [(Z(8{3i
^=^\=9"
b
import com.adt.bo.Result; &=)O:Jfa
import com.adt.dao.UserDAO; A{\?]]/
import com.adt.exception.ObjectNotFoundException; e
bpt/q[
import com.adt.service.UserManager; oQ-m
"[7-1} l
/** mmJnE
* @author Joa %2dzx[s
*/ u3qxG3
publicclass UserManagerImpl implements UserManager { ;8PO}{rD
giu{,gS0?M
private UserDAO userDAO; E`_T_O=P
B /uaRi%
/** %C`P7&8m=O
* @param userDAO The userDAO to set. N,lr~6)
*/ C[%Qg=<
publicvoid setUserDAO(UserDAO userDAO){ Az y`4
this.userDAO = userDAO; .g}N@
} BNJ0D
Z:^#9D{
/* (non-Javadoc) M>5OC)E
* @see com.adt.service.UserManager#listUser + Fo^NT
BAXu\a-C_
(org.flyware.util.page.Page) (/$-2.@
*/ Y _`JS;
public Result listUser(Page page)throws z4_B/Q
OR6vA5J
HibernateException, ObjectNotFoundException { :z P:4NW
int totalRecords = userDAO.getUserCount(); ^BLO}9A{P
if(totalRecords == 0) 1_S]t[?I/
throw new ObjectNotFoundException nZnqXclzxn
TO89;O
("userNotExist"); \{ | GK
page = PageUtil.createPage(page, totalRecords);
0<v5_pB
List users = userDAO.getUserByPage(page); PP$2s]{
returnnew Result(page, users); AP%R*0]
} >?K=l]!(*
W7A!QS
} Ox#vW6;)
G7CkP
U&6A)SW,k
(${:5W
,Tar?&C:
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 \&+Y;:6
}*rS g .
询,接下来编写UserDAO的代码: ]wDqdD y7S
3. UserDAO 和 UserDAOImpl: qdZ ^D
java代码: eY#^vB
Kd 1=mC
3'x>$5W
/*Created on 2005-7-15*/ v@Eb[7Kq/1
package com.adt.dao; _+9i
|U1 [R\X
import java.util.List; "{~FEx4
]cP%d-x}
import org.flyware.util.page.Page; zAM9%W2v_
@~s5 {4
import net.sf.hibernate.HibernateException; dakHH@Q
;UgwV/d
/** @k;65'"Q
* @author Joa Dks n
*/ Drtg7v{@\
publicinterface UserDAO extends BaseDAO { OKm,iIp]
?bM%#x{e
publicList getUserByName(String name)throws Uf+y$n-
TYD( 6N
HibernateException; !m:WoQ/
;"IWm<]h;-
publicint getUserCount()throws HibernateException; Sak^J.~G[
;6R9k]5P%
publicList getUserByPage(Page page)throws kJ"rRsK
kwUUvF7w
HibernateException; 9Br+]F_i
g7?[}?]3"p
} 8K9HFT@yV
w^8Q~3|7
|sr\SCx
9^g8VlQdT
sx azl]
java代码: !VIxEu^ke
}iDRlE,
C ibfuR
/*Created on 2005-7-15*/ Dti-*LB1
package com.adt.dao.impl; PTe$dPB
5P<1I7d
import java.util.List; 0vLx={i
1J1Jp|j.
import org.flyware.util.page.Page; *A!M0TK?i,
A4(L47^
import net.sf.hibernate.HibernateException; XM!oN^
import net.sf.hibernate.Query;
,d/$!Yf
{@L{l1|0
import com.adt.dao.UserDAO; gQik>gFr
!bLCha\
/** mY"Dw^)
* @author Joa 6{i0i9Tb
*/ u,iiS4'Ze
public class UserDAOImpl extends BaseDAOHibernateImpl "JmbYb#Z
yxx_%9 X
implements UserDAO { 4w%hvJ
Bn8&~
/* (non-Javadoc) !lzj.|7=1
* @see com.adt.dao.UserDAO#getUserByName ynra%"sd
"UD)3_R
(java.lang.String) 0y<9JvN$9
*/ 9Oj b~
publicList getUserByName(String name)throws ,9^ 5
[wSoZBl
HibernateException { U7fpaxc-
String querySentence = "FROM user in class hb~d4J=S
=CFg~8W
com.adt.po.User WHERE user.name=:name"; *g}==o`
Query query = getSession().createQuery PT,*KYF_O"
,e$RvFB
(querySentence); <hy!B4
query.setParameter("name", name); 8bMw.u=F
return query.list(); m8L %!6o
} \4$Nx/@Q}
?~.9:93
/* (non-Javadoc) E l.eK9L
* @see com.adt.dao.UserDAO#getUserCount() dk]
*/ (:~_#BA
publicint getUserCount()throws HibernateException { pvt/{
int count = 0; Ap\]v2G
String querySentence = "SELECT count(*) FROM 3@eI? (N
~7}no}7
user in class com.adt.po.User"; sR PQr?
Query query = getSession().createQuery _d~GY,WTdO
|:(B I5&S
(querySentence); k(>J?\iNW
count = ((Integer)query.iterate().next 6k,@+@]t.
0|va}m`<3G
()).intValue(); nq7)0F%e
return count; >/.jB/q
} /:A239=+ ?
gjT`<CW
/* (non-Javadoc) oIE(`l0l
* @see com.adt.dao.UserDAO#getUserByPage n$j B"1
hHw1<! M
(org.flyware.util.page.Page) jc6~V$3
*/ nC/T$
#G
publicList getUserByPage(Page page)throws \K9Y@jnr
coaJDg+
HibernateException { 7m8:odeF
String querySentence = "FROM user in class 6"?#s/fk
lKI]q<2
com.adt.po.User"; ,trh)ZZYW|
Query query = getSession().createQuery \iEJ9V
ZKI` ;
(querySentence); Ca"i<[8
query.setFirstResult(page.getBeginIndex()) !Y^$rF-+
.setMaxResults(page.getEveryPage()); &e[Lb:Uk)
return query.list(); _jkJw2+s\
}
v/KTEM
B7{j$0fm*
} ]6=opvm
+W>tdxOh
V /OW=WCzN
R'K /\
~c1~)QzZ
至此,一个完整的分页程序完成。前台的只需要调用 u_WW
uo
NFIFCy!
userManager.listUser(page)即可得到一个Page对象和结果集对象 }?{. 'Hv0
\<%FZT_4~
的综合体,而传入的参数page对象则可以由前台传入,如果用 @J@bD+Q+0
#lVSQZO~a
webwork,甚至可以直接在配置文件中指定。 r
Z5eXew6
YRl4?}r2
下面给出一个webwork调用示例: v Ma$JPauI
java代码: 71&`6#
rUiUv(q
)[sSCt]
/*Created on 2005-6-17*/ #@5 jOi
package com.adt.action.user; CA"`7<,
n |,}
import java.util.List; 4P24ySy9F
B;{sr'CP
import org.apache.commons.logging.Log; 9qZ|=r]y'
import org.apache.commons.logging.LogFactory; SLd9-N}T
import org.flyware.util.page.Page; MT&q~jx*
gY=+G6;=<
import com.adt.bo.Result; HZ2 zL17
import com.adt.service.UserService; KRcg
import com.opensymphony.xwork.Action;
93`
QPF[D7\
/** |4Q><6"G
* @author Joa ',RR*{I
*/ +n`^W(
publicclass ListUser implementsAction{ v:j4#pEWD
P|)SXR
privatestaticfinal Log logger = LogFactory.getLog Sag\wKV8
VHws9)
(ListUser.class); Xg"Mjmr
LyXABQ]
private UserService userService; 1hp@.Fv
@1[LD[<
private Page page; 9=~jKl%\vJ
)=D9L
privateList users; 7
~ Bo*UM
wY}+d0Ch
/* ~RE`@/wQ]
* (non-Javadoc) Y.Ew;\6U
* 0MzHr2?'P
* @see com.opensymphony.xwork.Action#execute() 3?/}
*/ |y=D^NTG
publicString execute()throwsException{ #$fFp
Result result = userService.listUser(page); *m]%eU(
page = result.getPage(); |b7>kM}"
users = result.getContent(); {k~$\J?.
return SUCCESS; 17qrBG-/MD
} ck<4_?1]
K<_H`k*x
/** PwNLJj+%
* @return Returns the page. q+G1#5
*/ vqxTf)ys
public Page getPage(){
n#]G!7
return page; `0 F"zu
} %BHq2~J
+Q_Gm3^
/** pV-.r-P
* @return Returns the users. qC|re!K
*/ $S cjEG:6
publicList getUsers(){ d ly 0874
return users; &k{@:z
} ;[zx'e?!
h/w- &7t
/** ,wEM
* @param page Em.?
* The page to set. `RzM)ILl
*/ =XS'V*
publicvoid setPage(Page page){ wYawG$@_
this.page = page; p9sxA|O=y
} :3Jh f$
I5"=b}V5
/** u})JQ<|
* @param users \)"qN^we
* The users to set. ?%0i,p@<
*/ -jw=Iyv
publicvoid setUsers(List users){ "7
4 L
this.users = users; ]V]o%onW
} ,^,J[F
bU,&|K/
/** BPOWo8TqD^
* @param userService &]c9}Ic
* The userService to set. dCyQC A[
*/ wb9zJAsc
publicvoid setUserService(UserService userService){ }w@nZG ^&
this.userService = userService; Y\x
Xo?
} Qqaf\$X
} J8D-a!
QBo^{],
tr} $82Po
wLbnsqa
NV;tsuA|
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, \^:f4ZT
Te13Af~
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 gy[uqm_ T
0\o'd\
么只需要: ?k?Hp:8?=
java代码: s`2o\]
zc(7p;w#p
ZqGq%8\.s
<?xml version="1.0"?> S9BJjo
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork n(+:l'#HJ
pVY.&XBZ$
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 5VcYdu3
#,;k>2j0
1.0.dtd"> ouI0"R&@
M;bQid@BG
<xwork> *]=)mM#
m
;vNA
<package name="user" extends="webwork- 5f5`7uVJF
s_8!x
interceptors"> uQNoIy J)
1WKDG~
<!-- The default interceptor stack name W2k~N X#@
sOW|TN>y\
--> J.d `tiN
<default-interceptor-ref w?C\YKF7
?m.4f&X
name="myDefaultWebStack"/> $p@g#3X`
{Q"<q`c
<action name="listUser" tpD?-`9o
StVv"YY
class="com.adt.action.user.ListUser"> b6(yyYdF
<param BkF[nL*|
5*r6#[S\
name="page.everyPage">10</param> ~eP2PG
<result ;D7jE+
A!~o?ej
name="success">/user/user_list.jsp</result> g/J!U8W"
</action> @wPmx*SF
zkOgL9
(_8
</package> 73.b9mF
\4[Ta,;t
</xwork> tQ67XAb
{mQJ6
G'ny
pf_ /jR
2^aTW`>L
>seB["C
BSY#xe V
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 SOL=3hfb^
>vU
Hf`4T
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 bW]+Og
yN.D(ZwF:
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 GdU
W$.
%ab79RS]C
;<A/e
5dk,!Cjg
YovY0nO
我写的一个用于分页的类,用了泛型了,hoho v=>Gvl3&U
ccSS au5N
java代码: v#FUD-Z
C(t/:?(y
96avgyc
package com.intokr.util; luT8>9X^:a
qu%s 7+
import java.util.List; S8VR#
'Ot[q^,KRG
/** l?o-
p
* 用于分页的类<br> 4o3GS8
* 可以用于传递查询的结果也可以用于传送查询的参数<br> `N|CL
* %K7}yy&9C
* @version 0.01 cw.7YiU
* @author cheng (% P=#vZ
*/ s|T7)PgR
public class Paginator<E> { F{,O+\
privateint count = 0; // 总记录数 I\~V0<"jI
privateint p = 1; // 页编号 *zWn4BckN
privateint num = 20; // 每页的记录数 (/U1J
privateList<E> results = null; // 结果 @\?f77Of6
+IYSWR
/** z<>_*Lfj
* 结果总数 ^@2Vh*k
*/ #Au&2_O
publicint getCount(){ 6]S.1BP
return count; "_j7kYAl
} v_0!uT5~NE
ay4xOwcR
publicvoid setCount(int count){ k Dt)S$N4n
this.count = count; MavO`m&Cg
} =jt_1L4
4#q JX)/
/** FF/R_xnx
* 本结果所在的页码,从1开始 E,@UM$alP
* ZZ*k3Ce
* @return Returns the pageNo. [B`P]}gL:
*/ ;G]'}$`/q
publicint getP(){ :\_MA^<
return p; F.D1;,x
} C6~dN&q
/p0LtUMu
/** us%RQ8=k
* if(p<=0) p=1 zQ}N
mlk
* CaBS0'
n
* @param p 8zWPb
*/ [Gy'0P(EQ
publicvoid setP(int p){ V?BVk8D};
if(p <= 0) Pltju4.:C
p = 1; K3DJ"NJ<Ji
this.p = p; -d'|X`^nE
} GNc|)$
,0]28D
/** z_@zMLs
* 每页记录数量 FaE orQ
*/ g"S+V#R
publicint getNum(){ d
A{Jk
return num; |"w<CKlQ
} J94YMyOo
GuvF
/** |LE++t*X~
* if(num<1) num=1 GQq'~Lr5
*/ LB7I`W
publicvoid setNum(int num){ uTGvXKL7
if(num < 1) lG>e6[Wc
num = 1; ^\jX5)2{
this.num = num; W%K8HAP "
} `|Z@UPHzG
z,YUguc|
/** S=SncMO nE
* 获得总页数 Cpv%s 1M
*/ $4JX#lkt
publicint getPageNum(){ }tO<_f))
return(count - 1) / num + 1; PM!t"[@&
} $i~`vu*
y/hvH"f
/** v=1S
* 获得本页的开始编号,为 (p-1)*num+1 i!x5T%x_
*/ @|%ICG c
publicint getStart(){ eh4"_t
return(p - 1) * num + 1; S@NhEc
} 3MJWC o-[
%MZDm&f>Kk
/** O \8G~V
5"
* @return Returns the results. Ia:puks=
*/ mIEaWE;E"
publicList<E> getResults(){ _J~ta.
return results; ik0Q^^1?Y
} n4T2'e
p+UHJ&
public void setResults(List<E> results){ 4Xk;Qd
this.results = results; F6]!?@
} 4 ~YQ\4h=
Prz+kPP
public String toString(){ :k(t/*Nl3
StringBuilder buff = new StringBuilder E/$@ud|l"
{<4?o?
1g
(); X]U"ru{1q
buff.append("{"); yPG\ &Bo
buff.append("count:").append(count); `+BaDns
buff.append(",p:").append(p); IYg3ve`x
buff.append(",nump:").append(num); TxxB0
buff.append(",results:").append nk$V{(FJ
o+Ti$`2<O7
(results); ur,"K'w
buff.append("}"); bTy)0ta>AF
return buff.toString(); <;0N@
} ';|>`<
| 4oM+n;Y
} J~'Q^O3@
uNZ>oP>
NF(IF.8G