Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 }<WJR Y6j
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 QVjHGY*R
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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 v_zt$bf{Y
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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 hwGK),?"+
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。 O}"oz3H
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分页支持类: PMP{|yEx"
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java代码: "=a3"/u
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package com.javaeye.common.util; jV2H61d
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import java.util.List; nZioFE}
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publicclass PaginationSupport { OH@"]Nc~
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publicfinalstaticint PAGESIZE = 30; ZFLmD|q#{
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privateint pageSize = PAGESIZE; SNqSp.>-U"
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privateList items; _\>y[e["p
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privateint totalCount; x/<ow4C
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privateint[] indexes = newint[0]; N[
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privateint startIndex = 0; k^oSG1F
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public PaginationSupport(List items, int a[hF2/*
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totalCount){ uUfw"*D
setPageSize(PAGESIZE); Ij(dgY
setTotalCount(totalCount); XEiVs\) G
setItems(items); \ZRII<k5)
setStartIndex(0); ()6%1zCO
} A'w+Lc.2
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public PaginationSupport(List items, int L<V20d9
b=Nsz$[
totalCount, int startIndex){ !5dn7Wuj
setPageSize(PAGESIZE); oVw4M2!"K
setTotalCount(totalCount); 21OfTV-+3
setItems(items); /K!)}f(6
setStartIndex(startIndex); 3@=<4$
} }!^h2)'7
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public PaginationSupport(List items, int Q%O9DCi
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totalCount, int pageSize, int startIndex){ .Vt|;P}
setPageSize(pageSize); K21Xx`XK
setTotalCount(totalCount); ;,-)Z|W
setItems(items); |Kd6.Mx
setStartIndex(startIndex); @ fMlbJq
} vE9"1M
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publicList getItems(){ '\{ OQH
return items; HVvm3qu4
} <uIPv
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publicvoid setItems(List items){ Fe[6Y<x+:
this.items = items; sA6HkB.
} ?e-rwaW
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publicint getPageSize(){ _,^f,WO~
return pageSize; F-@yH
} xLIyh7$t
_LF'0s*
publicvoid setPageSize(int pageSize){ 8!v|`Ky
this.pageSize = pageSize; `x=kb;
} DQhHU1
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publicint getTotalCount(){ I&|8
qx#
return totalCount; fyUW;dj
} qF3S\
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publicvoid setTotalCount(int totalCount){ _$*-?*V&
if(totalCount > 0){ 'tTlBf7#
this.totalCount = totalCount; cV:Q(|QC
int count = totalCount / +PYR
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pageSize; >]}VD "\
if(totalCount % pageSize > 0) 3=]/+{B
count++; TPb&";4ROf
indexes = newint[count]; a?Om;-i2`S
for(int i = 0; i < count; i++){ ip'v<%,Q3"
indexes = pageSize * -T+yS BO_3
[
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i; E2
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} Ew}GPJ
}else{ H?opG<R=ek
this.totalCount = 0; fx 08>r
} L,_U co
} -C^qN7Bz
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publicint[] getIndexes(){ >`30 ib
return indexes; NO*~C',cI/
} _)-2h[
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publicvoid setIndexes(int[] indexes){ N
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this.indexes = indexes; J'cE@(US
} .WOF:Nu4
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publicint getStartIndex(){ M-Nn \h$,
return startIndex; KI<x`b
} f`8fNt
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publicvoid setStartIndex(int startIndex){ ZbH6$2r
if(totalCount <= 0) D622:Y886
this.startIndex = 0; Zo-Au
elseif(startIndex >= totalCount) zh !/24p9
this.startIndex = indexes JmF`5
J!rZskd
[indexes.length - 1]; -'W:P'BG
elseif(startIndex < 0) P)TeF1~T
this.startIndex = 0; ?fs#K;w
else{ ^<yM0'0t
this.startIndex = indexes XSZjuQ<[3
:\#]uDT2=
[startIndex / pageSize]; VyU!r*
o
} r'}#usB(
} \@2sI
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publicint getNextIndex(){ /9y'UKl7[
int nextIndex = getStartIndex() + !x:w2
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pageSize; Y!E|X 3
if(nextIndex >= totalCount) 1?+)T%"
return getStartIndex(); Z?",+|4
else '.&,.E&{$
return nextIndex; y(#F&^|
} hYCyc-W
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publicint getPreviousIndex(){ ZG)C#I1;O
int previousIndex = getStartIndex() - Jf2:[Mq
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pageSize; a7NX~9g
if(previousIndex < 0) K3UG6S\B
return0; Q!%CU8!`&
else I(WND/&
return previousIndex; $PbN=@
} Y@'1}=`J
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} EZiGi[t7
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抽象业务类 1[`l`Truz
java代码: nBiA=+'v
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/** a( {`<F
* Created on 2005-7-12 &<i>)Ss
*/ U7fE6&g
package com.javaeye.common.business; g?o$:>c
/[#{#:lo2
import java.io.Serializable; ;/{Q4X{
import java.util.List; I0jEhg%JZ
Iei4yDv ;
import org.hibernate.Criteria; J&:0ytG
import org.hibernate.HibernateException; +TX
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import org.hibernate.Session; dl$l5z\
import org.hibernate.criterion.DetachedCriteria; _5YL !v&
import org.hibernate.criterion.Projections; ;1OTK6
import O,1u\Zy/
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org.springframework.orm.hibernate3.HibernateCallback; "AVj]jR
import yxQAO_C
\&qVr1|
org.springframework.orm.hibernate3.support.HibernateDaoS ?R{?Qv
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upport; f,a4LF
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import com.javaeye.common.util.PaginationSupport; Q}.y"|^
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public abstract class AbstractManager extends _&![s]
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`;}).
HibernateDaoSupport { L,4^Of
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privateboolean cacheQueries = false; x?<5=,
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privateString queryCacheRegion; Q6W)rJ[|
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publicvoid setCacheQueries(boolean ti#sh{t
];2eIe
cacheQueries){ h+^T);h};|
this.cacheQueries = cacheQueries; n0i&P9@B1
} FfgJ
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publicvoid setQueryCacheRegion(String xNqQbkF
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queryCacheRegion){ B# H
this.queryCacheRegion = IFTW,9hh
q(p0#Mk,E
queryCacheRegion; eB@i)w?@o
} =K>Z{%i
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publicvoid save(finalObject entity){ aC$g(>xFt
getHibernateTemplate().save(entity); B+DRe 8
} \j;uN#)28
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publicvoid persist(finalObject entity){ lM1!2d'P
getHibernateTemplate().save(entity); R39R$\
} 5)oIPHXw
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publicvoid update(finalObject entity){ "=n8PNV/
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getHibernateTemplate().update(entity); ;Gs**BB&
} .}<B*e=y
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publicvoid delete(finalObject entity){ @
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getHibernateTemplate().delete(entity); pNJM]-D]m~
} .-Lqo=o\
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publicObject load(finalClass entity, \
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finalSerializable id){ &"h!SkX/
return getHibernateTemplate().load ,<
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(entity, id); QPcB_wUqu
} >oNk(.
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publicObject get(finalClass entity, GDB>!ukg
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finalSerializable id){ +=k|(8Js#
return getHibernateTemplate().get l.W:6",w
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(entity, id); KUyJ"q<W
} YcV~S#b
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publicList findAll(finalClass entity){ k0IU~y%
return getHibernateTemplate().find("from ~=mM/@HD
feW9>f;
" + entity.getName()); M<srJ8|'
} NFc8"7Mz}
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publicList findByNamedQuery(finalString RGLA}|
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namedQuery){ R*0F)M
return getHibernateTemplate 6v#G'M#r
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().findByNamedQuery(namedQuery); `@D4?8_
} !gf3%!%
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publicList findByNamedQuery(finalString query, VC(|t} L4
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finalObject parameter){ 0cUt"(]
return getHibernateTemplate ~m?~eJK#a
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().findByNamedQuery(query, parameter); j2Y(Q/i
} o?FUVK
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publicList findByNamedQuery(finalString query, { bn#:75r
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finalObject[] parameters){ 8Q -F
return getHibernateTemplate \W^+vuD8
hob$eWgr
().findByNamedQuery(query, parameters); >pvg0Fh
} J"%}t\Q
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publicList find(finalString query){ ,P@-DDJ
return getHibernateTemplate().find I7^X;Q
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(query); J6ShIPc
} S\;.nAR
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;
publicList find(finalString query, finalObject veg!mY2&
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parameter){ (v:ek_
return getHibernateTemplate().find _ng=5
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(query, parameter); jsd]7C
} >wO$Vu
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public PaginationSupport findPageByCriteria yGGB
qU*&49X
(final DetachedCriteria detachedCriteria){ {b0&qV
return findPageByCriteria X6GkJ
R
xevP2pYG:
(detachedCriteria, PaginationSupport.PAGESIZE, 0); '#PqI)P
} &Z!K]OSY
.]s(c!{y
public PaginationSupport findPageByCriteria >-5Gt
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(final DetachedCriteria detachedCriteria, finalint `{lAhZ5
ZWRRh^
startIndex){ RrdtU7i3
return findPageByCriteria xTFrrmxOf
Df:7P>
(detachedCriteria, PaginationSupport.PAGESIZE,
)1nCw
=Z .V+4+
startIndex); 3u0<v%Qi
} x36#x
L@n6N|[_
public PaginationSupport findPageByCriteria Z<|_+7T
-jtC>_/
(final DetachedCriteria detachedCriteria, finalint O0wCb
b}Hl$V(uD
pageSize, k3>ur>aW
finalint startIndex){ YG 5Z8@kH
return(PaginationSupport) IgVo%)n
q
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getHibernateTemplate().execute(new HibernateCallback(){ V l~Y
publicObject doInHibernate p=_XMh`;
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(Session session)throws HibernateException { 0YpiHoM
Criteria criteria = r3H}*Wpf
A`
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detachedCriteria.getExecutableCriteria(session); 2'<=H76
int totalCount = x #tu
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((Integer) criteria.setProjection(Projections.rowCount S}w.#tyEn
w~$c= JO#
()).uniqueResult()).intValue();
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criteria.setProjection 5&<d2EG6l'
k)5_1y
(null); _iGU|$a
List items = iL0jpa<}
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criteria.setFirstResult(startIndex).setMaxResults RF4$
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(pageSize).list(); Ac[|MBaF
PaginationSupport ps = S"P9Nf?9
;;YcuzQI3
new PaginationSupport(items, totalCount, pageSize, oF;%^XFp
Foe>}6~{?
startIndex); dgco*TIGO
return ps; v;fJM5PA
} s~Lfi.
}, true); :J Gl>V
} 'n^2|"$sH
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public List findAllByCriteria(final Jm %ynW
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DetachedCriteria detachedCriteria){ !_U37Uj<m
return(List) getHibernateTemplate [arTx^
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().execute(new HibernateCallback(){ DIG0:)4R.
publicObject doInHibernate a1g6}ym\
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(Session session)throws HibernateException { jcEs10y
Criteria criteria = f`hyYp`d5
egI{!bZg'\
detachedCriteria.getExecutableCriteria(session); ,pyQP^u-
return criteria.list(); QGH
h;
} 1m>^{u
}, true); |oe!P}u
} ?{
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public int getCountByCriteria(final g>~cs_N@
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DetachedCriteria detachedCriteria){ 9Hf*cQ
Integer count = (Integer) 83KfM!w
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getHibernateTemplate().execute(new HibernateCallback(){ 3z,v#2
publicObject doInHibernate X~v4"|a
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(Session session)throws HibernateException { IjG5X[@
Criteria criteria = 1mJbQ#5
tS\=<T
detachedCriteria.getExecutableCriteria(session); ZjU=~)O}H
return GA|/7[I}
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criteria.setProjection(Projections.rowCount ^uyNv-'F
bKk CW
()).uniqueResult(); [1z{T(dh
} brg":V1a
}, true); j|VXC(6P,
return count.intValue(); d?:`n9`
} / <JY:1|
} 3<c*v/L{C\
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b/}'Vf[
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用户在web层构造查询条件detachedCriteria,和可选的 <fNGhmL
p QluGIX0V
startIndex,调用业务bean的相应findByCriteria方法,返回一个 [J~aAB
z*6$&sS\>
PaginationSupport的实例ps。 ZV!R#Xv
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ps.getItems()得到已分页好的结果集 sf Dg/ a
ps.getIndexes()得到分页索引的数组 &&;ex9
ps.getTotalCount()得到总结果数 P?^JPbfV
ps.getStartIndex()当前分页索引 mT96]V\
ps.getNextIndex()下一页索引 eh$G.-2N
ps.getPreviousIndex()上一页索引 XjX 2[*l
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 BSN6|W
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 GF&_~48GD
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一下代码重构了。 S#,+Z7
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我把原本我的做法也提供出来供大家讨论吧: xXORIlD
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首先,为了实现分页查询,我封装了一个Page类: PmHd9^C
java代码: ]de\i=?|
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/*Created on 2005-4-14*/ iBucT"d]
package org.flyware.util.page; 5i6VZv
UL&} s_
/** -(!uC+BZX
* @author Joa Kk7GZ
*
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*/ \fTTkpM
publicclass Page { fTBVvY4(
k!&:(]
/** imply if the page has previous page */ z^'n*h
privateboolean hasPrePage; 7m\vRMK
-!l^]MU
/** imply if the page has next page */ L${m/@9
privateboolean hasNextPage; :WVSJ,. !
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/** the number of every page */ f_rp<R>Uu
privateint everyPage; 6Z Xu,ks}
x.ba|:5
/** the total page number */ hqL+_|DW
privateint totalPage; 8yn4}`Nc@
0 <g{ V
/** the number of current page */ )Bo]=ZTJ^
privateint currentPage; ?z3]
DY8(g=TI|1
/** the begin index of the records by the current Yr=8!iR$
sds}bo
query */ s'TY[
privateint beginIndex; JRXRi*@
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K U$`!h
/** The default constructor */ /HZv
public Page(){ RpYcD
T<P0T<
} ]w!0u2K<Q\
wqP2Gw7jh6
/** construct the page by everyPage >VP5vkv=
* @param everyPage U9
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* */ 33 :@*
public Page(int everyPage){ yplG18
this.everyPage = everyPage; D*QYKW=)
} KU]ok '
Ps3~{zH`
/** The whole constructor */ `Ug tvo
public Page(boolean hasPrePage, boolean hasNextPage, $Zxt&a
t!jYu<P
"TNVD"RLY
int everyPage, int totalPage, @MOCug4
int currentPage, int beginIndex){ CcY7$D
this.hasPrePage = hasPrePage; NO2(vE
this.hasNextPage = hasNextPage; Vc _:*
this.everyPage = everyPage; ^^U%cuKg
this.totalPage = totalPage; pM9yOY
this.currentPage = currentPage; 2e59Ez%k6
this.beginIndex = beginIndex; ^&Q<tN7
} P#MK
&<Zdyf?[Ou
/** 8eN7VT eb
* @return \x(^]/@
* Returns the beginIndex. f}iU& 3S
*/ dw9Tf^V
publicint getBeginIndex(){ +P)ys#=
return beginIndex; {~'H
} &iBNO,v
!zR)D|w&
/** w#9_eq|3
* @param beginIndex n'M>xq_
* The beginIndex to set. w"~<h;
*/ \J3/keL
publicvoid setBeginIndex(int beginIndex){ u%B&WwHG
this.beginIndex = beginIndex; DW>ES/B8$(
} [EOVw%R
@PX\{6&
/** 2"X~ju
* @return id?E)Jy
* Returns the currentPage. OhFW*v
*/ "(f`U.
publicint getCurrentPage(){
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return currentPage; RgZOt[!.
} Hhl-E:"H`
/8c&Axuv
/** -{{[cTI
* @param currentPage X#`dWNrN
* The currentPage to set. C?o6(p"b
*/ )+EN$*H
publicvoid setCurrentPage(int currentPage){ |>+uw|LtZ
this.currentPage = currentPage; |##GIIv;i
} t,HFz6
! %Ny0JkO
/** ?aWx(dVQ
* @return :o8MUXH$
* Returns the everyPage. '!Wvqs
*/ pO]8
dE0
publicint getEveryPage(){ 2hq\n<
return everyPage; cP rwW6
} vFhz!P~
e.8$ga{
/** 7u|B ](FS
* @param everyPage wk @,wOt
* The everyPage to set. [_.n$p-
*/ 24B<[lSK
publicvoid setEveryPage(int everyPage){ iKAusWj
this.everyPage = everyPage; 3i=Iu0
} HdNnUDb$B
!0"nx{7.
/** N'?u1P4G
* @return bK*~ol
* Returns the hasNextPage. ^RNOcM|
*/ S|AjL
Ng#
publicboolean getHasNextPage(){ O|'1B>X
return hasNextPage; Ll}yJ#3,
} U>Gg0`>
!20XsO
/** Bp_wnd
* @param hasNextPage D*2\{W/
* The hasNextPage to set. Gu;OVLR|
*/ bRsTBp;R`I
publicvoid setHasNextPage(boolean hasNextPage){ tj5giQ3DG)
this.hasNextPage = hasNextPage; z7T0u.4Ss
} tC)6
~x]9SXD%
/** Dl,`\b@Fw3
* @return 2*1ft>Uty
* Returns the hasPrePage. RN9;kB)c
*/ RUo9eQIPD
publicboolean getHasPrePage(){ -LWK*q[J;*
return hasPrePage; 4XJiIa?
} Gquuy7[&
$NG++N
/** Mvcfk$pA
* @param hasPrePage Z :nbZHByh
* The hasPrePage to set. $k%Z$NSN=
*/ s([dGD$i
publicvoid setHasPrePage(boolean hasPrePage){ RE"^
)-
this.hasPrePage = hasPrePage; (.23rVvnT@
} rx!=q8=0R
/,tAoa~FA
/** 6v732;^
* @return Returns the totalPage. >:
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* 5?u}#zO
*/ |yY`s6Uq
publicint getTotalPage(){ NNkP\oh\
return totalPage; uY#TEjGh]
} ;_+uSalt
qoX@@xr1
/** vHKlLl>*2
* @param totalPage <02m%rhuW
* The totalPage to set. qJv[MBjk3B
*/ r'4:)~]s
publicvoid setTotalPage(int totalPage){ 55DE\<r
this.totalPage = totalPage; yVJ%+d:6
} zT9JBMNE:
j*R,m1e8
} "484n/D
1hmc,c
)!W45"l-3M
z`3( ,V
l67Jl"v
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 diT=x52
q|(W-h+
个PageUtil,负责对Page对象进行构造: (<c7<_-H
java代码: =|U@
TzG]WsY_
LKF/u` 0dP
/*Created on 2005-4-14*/ ^J/)6/TMXm
package org.flyware.util.page; zI;0&
WF2-$`x
import org.apache.commons.logging.Log; 4P8*k[.
import org.apache.commons.logging.LogFactory; Jjm|9|C,
K[?Xm"4
/** EqB)sK/3
* @author Joa N{Qxq>6 G
* ,xsH|xW
*/ ip:LcGt
publicclass PageUtil { ;;U:Jtn2
9Kv|>#zff
privatestaticfinal Log logger = LogFactory.getLog b[ w;i]2
!CY&{LEYn0
(PageUtil.class); q_fam,9
}JgYCsF/f
/** 8|g<X1H{M
* Use the origin page to create a new page 8y2+&#$
* @param page dK9Zg,DZL
* @param totalRecords kLP0{A
* @return LHYLC>J
*/ X$n(-65
publicstatic Page createPage(Page page, int zu\`1W^
7/IlL
totalRecords){ 3iNkoBCg
return createPage(page.getEveryPage(), $lwz-^1t.
f'Mop= .
page.getCurrentPage(), totalRecords); ,_
2x{0w:>
} N_gD>6I
DBH#)4do@
/** &#{dWObh
* the basic page utils not including exception r6.d s^
~/#1G.H
handler vGd1w%J-
* @param everyPage &, a3@i
* @param currentPage Fke//- R
* @param totalRecords 7<\C?`q"
* @return page C(?blv-vM0
*/ V-yUJ#f8[
publicstatic Page createPage(int everyPage, int tT%/r,
+0$/y]k
currentPage, int totalRecords){ r%]Qlt~K
everyPage = getEveryPage(everyPage); Jh/ E@}'
currentPage = getCurrentPage(currentPage); X` YwP/D
int beginIndex = getBeginIndex(everyPage, >l5$9wO
6<'K~1do:
currentPage); &2.u%[gO[q
int totalPage = getTotalPage(everyPage, (R}ii}&
5TKJWO.
totalRecords); OjE`1h\
boolean hasNextPage = hasNextPage(currentPage, OS-f(qXd+
3`.P'Fh(k
totalPage); 4@3[
boolean hasPrePage = hasPrePage(currentPage); %
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d
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returnnew Page(hasPrePage, hasNextPage, Wd,a?31|
everyPage, totalPage, 2tQ`/!m>v$
currentPage, $&I'o
5g5'@vMN
beginIndex); umEVy*hc
} v
$({C
LRb,VD:/Y
privatestaticint getEveryPage(int everyPage){ [\z/Lbn
,.
return everyPage == 0 ? 10 : everyPage; $4=f+ "z
} RVw9Y*]b
a:STQk V
privatestaticint getCurrentPage(int currentPage){ *?p|F&J
return currentPage == 0 ? 1 : currentPage; ^eq</5q D
} 3,X/,'
:Ixx<9c.
privatestaticint getBeginIndex(int everyPage, int 9"{W,'r&d
j7QX,_Q
currentPage){ `TLzVB-j3
return(currentPage - 1) * everyPage; {tP%epQ
} B2=\2<
o2H1N~e#c
privatestaticint getTotalPage(int everyPage, int \E1U@6a
Rqipkx
totalRecords){ uRV<?y%
int totalPage = 0; l,|%7-
a6xj\w
if(totalRecords % everyPage == 0) 7*+]wEs
totalPage = totalRecords / everyPage; >p\e0n
else `6=-WEo
totalPage = totalRecords / everyPage + 1 ; pL1i|O
hf6f.Z
return totalPage; )$%Z:
} $D1w5o-
RBKOM$7
privatestaticboolean hasPrePage(int currentPage){ :*514N
return currentPage == 1 ? false : true; ]jMKC8uz
} dtStTT
-NGK@Yk22
privatestaticboolean hasNextPage(int currentPage, X@N$Z{
I,@r5tKo
int totalPage){ ZfAzc6J?\
return currentPage == totalPage || totalPage == OTWkUB{
M)-6T{[IT
0 ? false : true; >pyj]y^3
} Njc%_&r
dhPKHrS
XUMX*
} w&h2y4
&7mW9]
.1 )RW5|c
I5ss0JSl/
={2!c0s
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。 nwI3|&
gO?44^hMe
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 @LE[ac
5/><$06rq
做法如下: ^?"\?M1
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 bp<^R
|H}sYp
的信息,和一个结果集List: ^y.nDs%ZT7
java代码: q-$`k
-F/st
BcWcdr+}9
/*Created on 2005-6-13*/ 6(&Y(/
package com.adt.bo; F4#g?R::U
'vV$]/wBF
import java.util.List; o?Nu:&yE
}3 m0AQ;K
import org.flyware.util.page.Page; }l0&a!C
0X|_^"!
/** eitu!=u
* @author Joa +%>:0mT
*/ NLd``=&
publicclass Result { 0BPMmk
K<sCF[
private Page page; k8nLo.O
rZ1Hf11C
private List content; v5ur&egVs
w FtN+
/** LE^G&<!
* The default constructor 'XOX@UH d
*/ -4#2/GXNO
public Result(){ b4 #R!
super(); ^4Am
%yyT
} 's
x\P[a
2(!fg4#+
/** =1;=
* The constructor using fields t/oN>mQG
* vEe NW
* @param page ?kw&=T!
* @param content Oc?+M 5
*/ +#J,BKul
public Result(Page page, List content){ f7de'^t9
this.page = page; XEM'}+d
this.content = content; <-Bx&Q
} T5Eseesp
?NNn:tiD
/** ._:nw=Y0<}
* @return Returns the content. X26
*/ %bXtKhg5eJ
publicList getContent(){
xFv;1Q
return content; JOnyrks
} 4JIYbb-a'
lG<hlYckv
/** I,6/21kO
* @return Returns the page. p4u5mM
*/ cTZ.}eLh
public Page getPage(){ ,38Eq`5&W
return page; Tsb{25`+
} 'fwU]Hm
n_D8JF
/** VzS&`d.h
* @param content @gGRm
* The content to set. 6~meM@
*/ DrW#v-d
public void setContent(List content){ ?wpB`
this.content = content; VxO%rq3
} M.}7pJ7f
#b0{#^S:
/** _1Z=q.sC
* @param page lt'I,Xt
* The page to set. Eu<1Bse;
*/ Mq%,lJA\
publicvoid setPage(Page page){ 7YWNd^FI
V
this.page = page; HHk)ZfWRo
} ni&*E~a
} 6X
g]/FD
}*U[>Z-eO
{[Q0qi =
@{
;XZb^
:B*}^g
2. 编写业务逻辑接口,并实现它(UserManager, OU DcY@x~
^
?hA@{T/1
UserManagerImpl) %%%fL;-y
java代码: Wk;5/
=/Aj
vW,snxK6y&
/*Created on 2005-7-15*/ q(^Q3
package com.adt.service; Ac k}QzXO
q]&.#&h
import net.sf.hibernate.HibernateException; U$&hZ_A
DmqX"x%P
import org.flyware.util.page.Page; t-%Q`V=[
8
}'|]JK
import com.adt.bo.Result; }71LLzG`/
=(AtfW^H
/** wz8PtfZ
* @author Joa Nw J:!
*/ ]bCq=6ZKR
publicinterface UserManager { e=P
"HMP$)d
public Result listUser(Page page)throws G*[P<<je_
$e%2t^ i.g
HibernateException; |V[9}E:
h
[K~]&
} 3-s}6<0v1
9W*+SlH@!
6Q|k7*,B
3ucP(Ex@tg
CCijf]+
java代码: 6w3R'\9
pz^<\
XP[uF ;w
/*Created on 2005-7-15*/ K5Wg"^AHY/
package com.adt.service.impl; I lR\
#
?gGt2O1J
import java.util.List; yQS+P8x&|]
yWPIIWHx!
import net.sf.hibernate.HibernateException; EER`?Sa(
S|AM9*k9
import org.flyware.util.page.Page; "pxzntY|
import org.flyware.util.page.PageUtil; &YP#M|
USJ-e
import com.adt.bo.Result; DbX{#4lx
import com.adt.dao.UserDAO; {aKqXL[UP
import com.adt.exception.ObjectNotFoundException; F#|O@.tDG
import com.adt.service.UserManager; P'@<:S|
UAS@R`?cI
/** Y+%sBqo@
* @author Joa < O*6T%;
*/ ;d.K_P
publicclass UserManagerImpl implements UserManager { Q }k.JS~#
8Chj
w wB
private UserDAO userDAO; !4@G3Ae22
#4LFG\s
/** ~Z/
^c,[:
* @param userDAO The userDAO to set. }Y(]6$uS
*/ $V>98M>j
publicvoid setUserDAO(UserDAO userDAO){ A?5E2T1L%.
this.userDAO = userDAO; `D7C?M#j]
} w^k;D,h
}]1BO
/* (non-Javadoc) 8cx=#Me
* @see com.adt.service.UserManager#listUser <hnCUg1
zZ-wG
(org.flyware.util.page.Page) -a Gcf]6
*/ f},oj4P\
public Result listUser(Page page)throws ^he=)rBb?
>M!xiQX
HibernateException, ObjectNotFoundException { _GQz!YA
int totalRecords = userDAO.getUserCount(); jo+w>
if(totalRecords == 0) |aQ"3d
throw new ObjectNotFoundException EUYCcL'G
YKZrEP4^
("userNotExist"); WnFG{S{s
page = PageUtil.createPage(page, totalRecords); *="8?Z
List users = userDAO.getUserByPage(page); `[#x_<\t
returnnew Result(page, users); :m=m}3/:
} OIHz I2{
?{"mP 'dD
} :yT-9Ze%q
$5`!Z%>/
+Z2MIC|Ud
3
vP(SIF
5M]z5}n/
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ek aFN\
cR-~)UyrO
询,接下来编写UserDAO的代码: Ax3W2s
3. UserDAO 和 UserDAOImpl: )Ag/Qep
java代码: !;@_VWR
38V3o`f
7DW]JK l
/*Created on 2005-7-15*/ lor8@Qz
package com.adt.dao; 3LR p2(A
;Lw{XqT
import java.util.List; M_0zC1
1xNVdI
import org.flyware.util.page.Page; :R6bq!
^_I} x)i*@
import net.sf.hibernate.HibernateException; M/D)".;
B
(/U3}w-
/** C`rLj5E%
* @author Joa |4)
*/ >4m'tZ8
publicinterface UserDAO extends BaseDAO { -37a.
a^qNJ?R!
publicList getUserByName(String name)throws Y-piL8Xc
_,Fny_u=;
HibernateException; 7x]4`#u
31^cz*V
publicint getUserCount()throws HibernateException; :vx$vZb
A|#`k{+1-
publicList getUserByPage(Page page)throws L(;WxHL
,iNv'
HibernateException; JN/UUfj
?q`0ZuAg\<
} \2[<XG(^
TG48%L
m4K* <
"\"DCDKmG
Eu}b8c
java代码: 5/",<1
6[qA`x#
1L7{p>;-dO
/*Created on 2005-7-15*/ 4!62/df
package com.adt.dao.impl; c97{Pu
?[TfpAtQ`
import java.util.List; 9A,Z|q/z5
idc`p?XP
import org.flyware.util.page.Page; seFGJfN\?f
t22;87&|
import net.sf.hibernate.HibernateException; `Ycf]2.,$
import net.sf.hibernate.Query; =d
2r6%v
-F&U
import com.adt.dao.UserDAO; h-a!q7]l
gieN9S
/** h+.{2^x
* @author Joa ! hd</_#
*/ yfQ5:X
public class UserDAOImpl extends BaseDAOHibernateImpl :nHKl
}K1 0Po'
implements UserDAO { 'XQ`g CF=
vD/NgRBww
/* (non-Javadoc) S>G?Q_&}?D
* @see com.adt.dao.UserDAO#getUserByName W+wA_s2&D
%t=kdc0=_
(java.lang.String) ~9^)wCM+
*/ 2I3h
MD0
publicList getUserByName(String name)throws K`&oC8p
O-]mebTvw
HibernateException { %R#L
String querySentence = "FROM user in class UsGa
vzzE-(\\e
com.adt.po.User WHERE user.name=:name"; -\ZcOXpMx=
Query query = getSession().createQuery
OV2-8ERS
.Ig+Dj{)
(querySentence); $CTSnlPq
query.setParameter("name", name); 2n><RZ/9
return query.list(); ~"pKe~h
} H>Q%"|
c0c|z
Ym
/* (non-Javadoc) `
8W*
* @see com.adt.dao.UserDAO#getUserCount() g
6]epp[8
*/ h'J|K^na
publicint getUserCount()throws HibernateException { hc
(e$##
int count = 0; ]3ONFa
String querySentence = "SELECT count(*) FROM &uP~rEJl+
[=O/1T
user in class com.adt.po.User"; sAo&
uZ
Query query = getSession().createQuery ^Jb
H?
bQe^Px5
!.
(querySentence); g71[6<D
count = ((Integer)query.iterate().next _(J&aY\
@3fn)YQ'
()).intValue(); 4=uhh
return count; Vc^HVyAx@n
} tH=P6vY
4tg<iH{
/* (non-Javadoc) f)]%.>
* @see com.adt.dao.UserDAO#getUserByPage MT(o"ltQ
%1pYEHn
(org.flyware.util.page.Page) #T`t79*N
*/ js1!9%BV
publicList getUserByPage(Page page)throws Sxjub&=
nEzf.[+9/
HibernateException { vVGDDDz/
String querySentence = "FROM user in class =4GSg1Biy
'|;X0fD
com.adt.po.User"; imQURC
Query query = getSession().createQuery 6y%0`!
b~dIk5>O
(querySentence); 1[_mEtM:]B
query.setFirstResult(page.getBeginIndex()) kq\)MQ"/X
.setMaxResults(page.getEveryPage()); |t$Ma'P
return query.list(); m*e{\)rd#
} .ROznCe}
!lo/xQ<
} rD>*j~_+P
=PGs{?+&O
4Llo`K4
j}b\Z9)!
XMG]Wf^%\<
至此,一个完整的分页程序完成。前台的只需要调用 cqxVAzb
x8GJY~:SW
userManager.listUser(page)即可得到一个Page对象和结果集对象 @p\}pY$T
(8_\^jJ
的综合体,而传入的参数page对象则可以由前台传入,如果用 U]a*uF~h
!3T&4t
webwork,甚至可以直接在配置文件中指定。 <nEi<iAY>U
|>@W
]CX[
下面给出一个webwork调用示例: -G6U$
java代码: +iOKbc'
!!Z?[rj
UA|u U5Q
/*Created on 2005-6-17*/ |Ph3#^rM?
package com.adt.action.user; j65<8svl
A$6$,h
import java.util.List; X$/2[o#g
>:lnt /N3
import org.apache.commons.logging.Log; ws4cF
N9P?
import org.apache.commons.logging.LogFactory; HaIM#R32T
import org.flyware.util.page.Page; ,AT[@
(XoH,K?{z
import com.adt.bo.Result; vm>b m
import com.adt.service.UserService; K_&4D'
import com.opensymphony.xwork.Action; [=~pe|8:
R:B^
/** .bio7c6
* @author Joa $\9~)Rq6
*/ v0L\0&+
publicclass ListUser implementsAction{ @IXsy
4[N^>qt =
privatestaticfinal Log logger = LogFactory.getLog j&k6O1_
jlxpt)0i
(ListUser.class); .1LCXW=
.YuJJJv
private UserService userService; av~5l4YL
6uR^%W8]
private Page page; n?V+dC=F}
_o8?E&d
privateList users; <I;2{*QI2
P9 Z}H(?C
/* 4WK3.6GN
* (non-Javadoc) 9?k_y ZV
* #KO,~]k5|e
* @see com.opensymphony.xwork.Action#execute() i&n'N8D@
*/ 0iJue&
publicString execute()throwsException{ j1(D]Z=\
Result result = userService.listUser(page); %;D.vKoh
page = result.getPage(); Q%f|~Kl-hd
users = result.getContent(); rXHv`ky
return SUCCESS; 9+pmS#>_
} {^N[("`
,UuH}E
/** =Qn ;_+Ct
* @return Returns the page. '}9JCJ
*/ /soKucN"h
public Page getPage(){ SV(]9^nW
return page; &
GreN
} PsZ
>P|e1
Ox-|JJ=
/** 12+>5BA
* @return Returns the users. {*ob_oc
*/ }-@`9(o`)
publicList getUsers(){ z0do;_x]E
return users; @62Mk},9 c
} h*<P$t
-!
K-Htb-
/** l\n@cQR
* @param page Rx+p.
* The page to set. wT{nu[=GH*
*/ CH<E,Z
C1T
publicvoid setPage(Page page){ gatB QwJb9
this.page = page; .e3+s*
} Q6r7.pk"SU
2j&AiD
/** ]H1I,`=@
* @param users T|6a("RL
* The users to set. ]i)j3WDz]
*/ mN19WQ(r
publicvoid setUsers(List users){ n9xAPB }
this.users = users; X<*U.=r)
} VZl6t;cn
0xXC^jx:
/** %p0xM
* @param userService f-71~
* The userService to set. $81*^
*/ :dqn h
publicvoid setUserService(UserService userService){ ih;]nJ]+-
this.userService = userService; "^]cQ"A
} TG5XSy
} I2nhqJy^
_> *jH'
~7Tc$
"I
6}oXP_0U
>cCR2j,r
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, E}tqQ*u
I}vmU^Y>
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
7?%k7f
B[4KX
么只需要: mFZ?hOyP.
java代码: 5EebPXBzB
\<)9?M :
AlIpsJ[UU
<?xml version="1.0"?>
MEGv}
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork KPj\-g'A
4sT88lG4n
1.0//EN" "http://www.opensymphony.com/xwork/xwork- u9EgdpD
e;[F\ov%
1.0.dtd"> os]8BScx
#hsx#x||
<xwork> c. 2).Jt,
Ch3jxgQY
<package name="user" extends="webwork- 7!JQB
#Q`dku%V:
interceptors"> la+[bm<v
$
.
9V&
<!-- The default interceptor stack name (X3Tav
hs$GN]
-->
S :<Nc{C
<default-interceptor-ref C
.~+*"Vw
LpqO{#ZG
name="myDefaultWebStack"/> e!=kWc
fV'ZsJ N
<action name="listUser" L=sYLC6d
20nP/e
class="com.adt.action.user.ListUser">
VN\W]jT
<param DRi<6Ob
N<-gI9_
name="page.everyPage">10</param> 1BpiV-]=
<result Us0EG\Y
#kaY0M
name="success">/user/user_list.jsp</result> ?}U(3
</action> ub\MlSr
/q`xCS
</package> Gf<'WQ[
Pf\D-1gi
</xwork> S9~+c
ap+JQ@b
zPjHsulK
X6@WwM~qz
~U@;gLoD
9E"vN
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 Wg<(ms dj
~ijVmWNk
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。 \(^nSy&N
P>NF.BCq
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 ;E3>ay6m8
*&^:T~|=!
U$WxHYo
M$>1L
O\"3J(y,
我写的一个用于分页的类,用了泛型了,hoho 4O)1uF;
V`XNDNJ:
java代码: JSCZ{vJ$
b2OQtSr a
H?&Mbw
d
package com.intokr.util; 'kL#]
0+kH:dP{
import java.util.List; \%f q
sP;nGQ.eN
/** B1>/5hV}
* 用于分页的类<br> 4GY[7^
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ]v]qChZHd
* Of[XKFn_
* @version 0.01 =E.t`x=
* @author cheng VFURAYS
*/ I+[>I=ewa
public class Paginator<E> { ebUBrxZX
privateint count = 0; // 总记录数 7!EBH(,z
privateint p = 1; // 页编号 kT"Kyd
privateint num = 20; // 每页的记录数 0 yuW*z
privateList<E> results = null; // 结果 kt["m.
\KQ71yqY
/** (`c
[#0=n
* 结果总数 JGsx_V1t
*/ X[PZg{
publicint getCount(){ AGQ#$fh>7=
return count; J;{N72
} V'8s8H
$c:ynjL|P-
publicvoid setCount(int count){ :U3kW8;UMP
this.count = count; T|7}EAR=b
} :D%"EJ
C)@y5. G;
/** XWS%zLaK
* 本结果所在的页码,从1开始 [y'f|XN
* ZniB]k1
* @return Returns the pageNo. ]B%v+uaW
*/ v9w'!C)b
publicint getP(){ q Gw -tPD<
return p; mpI5J'>]
} &,c``z
0=* 8
/** ur$
_
* if(p<=0) p=1 G7qG$wd8h
* Tx|Ir+f6L
* @param p 2Ga7$q
*/ Y;@>b{s
publicvoid setP(int p){ [ sN EHf
if(p <= 0) x(etb<!jd
p = 1; B$ajK`x&I
this.p = p; p^%YBY#,H
} 7n8~K3~;
)uj Ex7&c
/** Rot@x r7Hc
* 每页记录数量 "?ucO4d
*/ }!"A!~&
publicint getNum(){ =(NB%}
return num; E^ P,*s
} yj;sSRT
PP;}e
/** !UG
7Uer
* if(num<1) num=1 3 Nreqq
*/ }.3nthgz
publicvoid setNum(int num){ J
pFfzb
if(num < 1) 1crnmJ!C
num = 1; ?t/~lv
this.num = num; x(hE3S#+
} '(f&P=[b
#E?(vA1
/** x_|UPF
* 获得总页数 4}_j`d/8|
*/ uw[<5
publicint getPageNum(){ *5vV6][
return(count - 1) / num + 1; %_+2@\
} TH; R
??PC
k1X
/** C\/xl#e<@
* 获得本页的开始编号,为 (p-1)*num+1 co~Pyj
*/ :=/85\P0SU
publicint getStart(){ i@P)a'W_
return(p - 1) * num + 1; <,Ue
0
} ?ooe'V@
wfU7G[
/** eqP&8^HP
* @return Returns the results. "^w]_^GD$d
*/
0Sle
publicList<E> getResults(){ q*\x0"mS/
return results; p<TpK )
} ?]Pmxp
H}
CN#+U,NZV
public void setResults(List<E> results){ xIxn"^'
this.results = results; 6|aKL[%6
} jGXO\:sO
ofPHmh`
public String toString(){ S0~2{G"v
StringBuilder buff = new StringBuilder =U#dJ^4P
CK,7^U
(); _d"b;4l
buff.append("{"); ^HV>`Pjd}=
buff.append("count:").append(count); (eCJ;%%k
buff.append(",p:").append(p); h\5OrD@L
buff.append(",nump:").append(num); x^kp^
/f
buff.append(",results:").append DB-l$rj
lDOCmdt@N
(results); :p]'32FA!
buff.append("}"); gCioq.
return buff.toString(); 4SlADvGl
} :YXX8|>
AG!w4Ky`
} Cnbz=z
:bz}c48%
[z9`)VIe