Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 [7g-M/jvY
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 O:
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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 DsD? &:
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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 @*- 6DG-f
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分页支持类: %tZrP$DQ
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java代码: 45$aq~%as
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package com.javaeye.common.util; &
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import java.util.List; 0PsQ
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publicclass PaginationSupport { jUgx
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publicfinalstaticint PAGESIZE = 30; ;sq xFF@
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privateint pageSize = PAGESIZE; 6Z2|j~
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privateList items; q">}3`k
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privateint totalCount; 7zJ2n/`m*
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privateint[] indexes = newint[0]; 5J1a8RBR
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privateint startIndex = 0; [!8bjc]c
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public PaginationSupport(List items, int 1<MJ3"60
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totalCount){ ;ceg:-Zqo
setPageSize(PAGESIZE); ccp9nXv
setTotalCount(totalCount); $J,$_O6
setItems(items); -m mQ]'.0
setStartIndex(0); kC6Y?g
} 4FZ/~Y1}
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public PaginationSupport(List items, int i~R+g3oi
p~""1m01,D
totalCount, int startIndex){ Sm?|,C3V
setPageSize(PAGESIZE); HDKY7Yr
setTotalCount(totalCount); Fp[49
setItems(items); W
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setStartIndex(startIndex); q5@Nd3~h
} MpvGF7H
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public PaginationSupport(List items, int _x#y
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totalCount, int pageSize, int startIndex){ 3>73s}3
setPageSize(pageSize); ]` A*7
setTotalCount(totalCount); VM\\.L
setItems(items); n<<arO"cv
setStartIndex(startIndex); ?~#[cx
} Z7[S698
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publicList getItems(){ nn$^iw`
return items; EM!S ;i
} s*Z
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publicvoid setItems(List items){ BI<9xl]a
this.items = items; 8}4.x3uw
} =MD)F
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publicint getPageSize(){ 8m
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return pageSize; aG4 ^xOD
} JP
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jUR*
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publicvoid setPageSize(int pageSize){ $ndBT+i
this.pageSize = pageSize; ]Y76~!N
} LTH,a?lD
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publicint getTotalCount(){ dnXu(e%
return totalCount; x_?K6[G&}
} ~i'!;'-_}
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publicvoid setTotalCount(int totalCount){ "&^KnWk=
if(totalCount > 0){ 7^UY%t
this.totalCount = totalCount; _v,Wl/YAp
int count = totalCount / $AMcU5^b7
nGc'xQy0
pageSize; _FS #~z'j
if(totalCount % pageSize > 0) nU\.`.39
+
count++; kApD D[ N
indexes = newint[count]; TlX:05/V8
for(int i = 0; i < count; i++){ ]VtP7Y
indexes = pageSize * KbK!4
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i; YN:Sn\`D 8
} M
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}else{ P6ka'!z
this.totalCount = 0; ]~f-8!$$R
} TeR bW
} !bnnUCTb\
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publicint[] getIndexes(){ Ukf:m&G
return indexes; 0JR)-*
} CtD<%v3`
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publicvoid setIndexes(int[] indexes){ j>
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this.indexes = indexes; yT7{,Z7t
} BePb8
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publicint getStartIndex(){ 85] 'I%gT
return startIndex; h4Arg~Or
} lU&2K$`
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publicvoid setStartIndex(int startIndex){ EQZ/v gho
if(totalCount <= 0) .RmoO\
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this.startIndex = 0; p<l+js(5|
elseif(startIndex >= totalCount) !,5qAGi0
this.startIndex = indexes DZb0'+jQ
aM,g@'.=
[indexes.length - 1]; 2~r2ErtS
elseif(startIndex < 0) 6Rq +=X
this.startIndex = 0; e},:QL0X
else{ xt`a":lr u
this.startIndex = indexes nKtRJ,>
:fy,%su
[startIndex / pageSize]; _z.CV<
} s*i,Ph
} HxLuJ
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publicint getNextIndex(){ IEJ)Q$GI#
int nextIndex = getStartIndex() + Txpj#JD
H/8u?OC
pageSize; (R RRG;*n#
if(nextIndex >= totalCount) 6!*zgA5M'
return getStartIndex();
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else J\'f5)k
return nextIndex; bS55/M w
} ^U,C])n
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publicint getPreviousIndex(){ ^r7KEeVD
int previousIndex = getStartIndex() - .i` -t"
%P#|
}
pageSize; a8k`Wog
if(previousIndex < 0) {c drMP@""
return0; 9]tW; ?
else M.)z;[3O
return previousIndex; >Apa^Bp
} ["ocZ? x
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} iF.f*3-NJB
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抽象业务类 92b}N|u
java代码: JV/:QV
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/** 5,|{|/
* Created on 2005-7-12 H,j_2JOY=
*/ ]f wW
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package com.javaeye.common.business; qk0cf~gz
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import java.io.Serializable; 2t{Tz}g*
import java.util.List; XZ8]se"C
&rG]]IO
import org.hibernate.Criteria; iP$>/ [I
import org.hibernate.HibernateException; &Fk|"f+
import org.hibernate.Session; X .K*</(g
import org.hibernate.criterion.DetachedCriteria; :inVwc
import org.hibernate.criterion.Projections; RcO.1@2
import [?2?7>D8
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org.springframework.orm.hibernate3.HibernateCallback; FS('*w&bP
import <5ULu(b&$
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org.springframework.orm.hibernate3.support.HibernateDaoS vn@sPT
/&c>*4)
upport; Uhyf
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import com.javaeye.common.util.PaginationSupport; 6W;`}'ap
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public abstract class AbstractManager extends {!.w}
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HibernateDaoSupport { Q!7mN?l
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privateboolean cacheQueries = false; n2[h`zm1{B
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privateString queryCacheRegion; yaHkWkl
=
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publicvoid setCacheQueries(boolean %?S[{ 4A&
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cacheQueries){ \3F)M`g
this.cacheQueries = cacheQueries; bIV9cpW
} 3z"%ht~;
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publicvoid setQueryCacheRegion(String Dx9k%G)!
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queryCacheRegion){ jz\>VYi(7
this.queryCacheRegion = 6hXh;-U
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queryCacheRegion; iI*qx+>f?
} 7|!Zx-}
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publicvoid save(finalObject entity){ 'I2[}>mj2
getHibernateTemplate().save(entity); TA#pA(k
} h 3 J&
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publicvoid persist(finalObject entity){ s)sT\crP@
getHibernateTemplate().save(entity); [DtMT6F3
} oj,;9{-
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publicvoid update(finalObject entity){ $lUz!mjG
getHibernateTemplate().update(entity); vrvi]
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} a5w E{K
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publicvoid delete(finalObject entity){ dXU6TCjU7
getHibernateTemplate().delete(entity); AD6 b
} H87k1^}HV
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publicObject load(finalClass entity, v|3mbApv
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finalSerializable id){ !!~r1)zN
return getHibernateTemplate().load G=kW4rAk
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(entity, id); Ov.oyke4
} O8LIKD_I[
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publicObject get(finalClass entity, v~YGef;D
)2:U]d%pk
finalSerializable id){ 6/Z_r0^O
return getHibernateTemplate().get Scmew
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(entity, id); )E6E}
} ^Q!A4qOQ
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publicList findAll(finalClass entity){ &nY#GHB
return getHibernateTemplate().find("from B?
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" + entity.getName()); C7&L9k~jf
} ;iUO1t)^
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publicList findByNamedQuery(finalString :n?rk/ F
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namedQuery){ u|Ng>lU
return getHibernateTemplate ~cfvL*~5
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().findByNamedQuery(namedQuery); SxX
} iU#"G" &
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publicList findByNamedQuery(finalString query, bhfC2@
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finalObject parameter){ i> {0h3Y
return getHibernateTemplate UcB2Aauji
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().findByNamedQuery(query, parameter); YH{n
} 4-C'2?
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publicList findByNamedQuery(finalString query, F-D$Y?m
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finalObject[] parameters){ &NI\<C7_Gw
return getHibernateTemplate }CrWmJu0
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T
().findByNamedQuery(query, parameters); 6ywOL'OBM
} J{nA
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publicList find(finalString query){ hE4qs~YB!
return getHibernateTemplate().find ^ Qxv5HS2
)X8N|W>vh
(query); ! 'Hd:oD<
} =RofC9,
mRC
publicList find(finalString query, finalObject 7(<r4{1?
6E_YUk?KW
parameter){ *mW 2vJ/B
return getHibernateTemplate().find TW1#'G_#
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(query, parameter); nrbP3sf*
} +IlQZwm~
+Y>oNX1KN
public PaginationSupport findPageByCriteria df&.!7_R`
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(final DetachedCriteria detachedCriteria){ hsYv=Tw3C
return findPageByCriteria b]N&4t
s$^2Qp
(detachedCriteria, PaginationSupport.PAGESIZE, 0); nB4+*=$E+-
} Y6(=cm
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public PaginationSupport findPageByCriteria yI%q3lB}^
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(final DetachedCriteria detachedCriteria, finalint isFxo,R9r
4Wa*Pcj
startIndex){ y'O<*~C(X
return findPageByCriteria 1r3}
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(detachedCriteria, PaginationSupport.PAGESIZE, Xu|2@?l9
*dsI>4%m
startIndex); h]j>S
} ;f}
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public PaginationSupport findPageByCriteria 4AKPS&k;
9xFI%UOb#
(final DetachedCriteria detachedCriteria, finalint t~8H~%T>v
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pageSize, :Vw{ lB
finalint startIndex){ o3h>)4
return(PaginationSupport) Q2*
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\[ 4y
getHibernateTemplate().execute(new HibernateCallback(){ =uR3|U(.|u
publicObject doInHibernate (]zi;
.=9d3uWJ/
(Session session)throws HibernateException { 9q\_UbF
Criteria criteria = CW]Th-xc
@R (Op|9
detachedCriteria.getExecutableCriteria(session); A>_,tt
int totalCount = Q&/WVRD
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((Integer) criteria.setProjection(Projections.rowCount ]<C]&03))
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()).uniqueResult()).intValue(); j}6h}E&dEr
criteria.setProjection V~do6[(
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(null); i>dFpJ
List items = jWdZ]0m
F&
criteria.setFirstResult(startIndex).setMaxResults aP
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{xh5s<uOj
(pageSize).list(); )mjGHq2
PaginationSupport ps = h67{qY[J[
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new PaginationSupport(items, totalCount, pageSize, iU(B#ohW"
@ 'U`a4
startIndex); <-,y0Y'
return ps; '~1Zr uO
} nC)"% Sa
}, true); WuTkYiF
} L$y~\1-
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public List findAllByCriteria(final VCvf'$4(X
vJS}_j]_@
DetachedCriteria detachedCriteria){ oe!4ng[
return(List) getHibernateTemplate YGRb|P-
q$Ms7` a
().execute(new HibernateCallback(){ 0f_A"K
publicObject doInHibernate V/zmbo)
*p9k> )'J
(Session session)throws HibernateException { kfZ(:3W$
Criteria criteria = 0|8cSE<
i
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detachedCriteria.getExecutableCriteria(session); -<M+ $hK\
return criteria.list(); (!YJ:,!so
} Bx6,U4o*
}, true); @.`k2lxGd~
} fzvyR2 I
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public int getCountByCriteria(final .L]5,#2([
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DetachedCriteria detachedCriteria){ O\)Kg2
Integer count = (Integer) s!>9od6^
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getHibernateTemplate().execute(new HibernateCallback(){ ai;Q,Vy
publicObject doInHibernate .?LRt
$: |`DCC
(Session session)throws HibernateException { p(K^Zc
Criteria criteria = =E^/gc%X
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detachedCriteria.getExecutableCriteria(session); &0fV;%N
return yrl7
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criteria.setProjection(Projections.rowCount 5(E&jKn&
Mc!LC
.8
()).uniqueResult(); F^S]7{
} q8FpJ\
}, true); rS8\Vf]F
return count.intValue(); 'GiN^Y9dcc
} .w'b%M
} -=5~-72~
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用户在web层构造查询条件detachedCriteria,和可选的 ]@#wR
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 q/d?cLgl
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PaginationSupport的实例ps。 >Gk<a
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ps.getItems()得到已分页好的结果集 %[M0TE=J
ps.getIndexes()得到分页索引的数组
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ps.getTotalCount()得到总结果数 H)EL0
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ps.getStartIndex()当前分页索引 GIn%yB'
ps.getNextIndex()下一页索引 {2q0Ko<
ps.getPreviousIndex()上一页索引 8eYEi
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 (n7{?`Yid
#g0N/
,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 Fq5u%S
9yWf*s<
一下代码重构了。 I,HtW ),
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我把原本我的做法也提供出来供大家讨论吧: /e^) *r
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y
首先,为了实现分页查询,我封装了一个Page类: ` aF8|tc_
java代码: DT)][V^w
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/*Created on 2005-4-14*/ E)f9`][
package org.flyware.util.page; pV_zePyOn
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/** .:B>xg~2
* @author Joa );6f8H@G
* ?%Tx%
dB
*/ m<kJH<!j
publicclass Page { `Syfl^9B
x?0K'
/** imply if the page has previous page */ .XiO92d9
privateboolean hasPrePage; vyB{35p$
$p&eS_f
/** imply if the page has next page */ 3dLqlJ^7B
privateboolean hasNextPage; +`>E_+Mp
s/s&d pT*
/** the number of every page */ wU<j=lY?f
privateint everyPage; n:) [%on
GKSF(Tnj
/** the total page number */ KG9-ac
privateint totalPage; _~ei1
G.R
O!XSU,
/** the number of current page */ W*#5Sk
privateint currentPage; -C}"1|P!
?A_+G 5
/** the begin index of the records by the current JX[]u<h?
(xVx|:R[<H
query */ <eS/-W%n6
privateint beginIndex; wVnmT94
T]tu#h{
a
JMo r[*
/** The default constructor */ (w5cp!qW9J
public Page(){ %N&W_.F6
?wCX:?g
} F ]Zg
yRl
/** construct the page by everyPage Bp5ra9*5+~
* @param everyPage 9+s&|XS*
* */ YM'4=BlJHv
public Page(int everyPage){ l&e$:=;8
this.everyPage = everyPage; 3oH/34jj
} 9&.md,U '
C4.GtY8,d
/** The whole constructor */ K%mR=u#%&
public Page(boolean hasPrePage, boolean hasNextPage, Y,Rr[i"j
G)t-W%D&
q/ 54=8*h0
int everyPage, int totalPage, `XK\',
}F
int currentPage, int beginIndex){ l'wu-
this.hasPrePage = hasPrePage; nqUnDnP2c
this.hasNextPage = hasNextPage; -.8K"j{N
this.everyPage = everyPage; |pWu|M _'
this.totalPage = totalPage; t&q~ya/C
this.currentPage = currentPage; w4\
3*
this.beginIndex = beginIndex; #{J~
km /
} N#"l82^H*
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/** eL(<p]
* @return GN!
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* Returns the beginIndex. ;DYS1vG o
*/ y_Urzgm(
publicint getBeginIndex(){ F`x_W;\
return beginIndex; g)r{LxT# +
} =RRv&
"2r
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/** LPu*Lkx
* @param beginIndex (PGw{_
* The beginIndex to set. S2*sh2-&6
*/ ckY#oRQ1
publicvoid setBeginIndex(int beginIndex){ {j]cL!Od
this.beginIndex = beginIndex; 43M.Hj]
} bo\Ah/.
Q*PcO \Y!y
/** I#O"<0
*r
* @return a~_JTH4=t
* Returns the currentPage. ]YFjz/f
*/ .IdbaH
_a
publicint getCurrentPage(){ 4* >j:1
return currentPage; )?(Ux1:w)
} ln=fq:
/NCN wAj7
/** v^t7)nx^
* @param currentPage 2z;3NUL$n
* The currentPage to set. WlvT&W
*/ 4=|Q2qgFV
publicvoid setCurrentPage(int currentPage){ M80Q6K
this.currentPage = currentPage; pFNU~y'Kf
} NiW9/(;xB
(&/4wI^M
/** l9a81NF{s
* @return 4aBVO%t
* Returns the everyPage. ,-E'059
*/ Komdz/g
publicint getEveryPage(){ }s<;YC
return everyPage; z7`|N`$Z#s
} NFEr ,n
iz`>'wpC
/** hB.8\-}QMq
* @param everyPage md'wre3
* The everyPage to set. Er~KX3vF
*/ 0q-lyVZ^X
publicvoid setEveryPage(int everyPage){ ut560,h~
this.everyPage = everyPage; C{uT1`
} }kvix{
$[fq Th
/** 8_HBcZWs
* @return Nr2,m"R{
* Returns the hasNextPage. F9K0
*/ +<F3}]]
publicboolean getHasNextPage(){ PLs`Ci|`
return hasNextPage; tR'RB@kJ
} M`'DD-Q
8Z9>h:c1
/** 'ZMh<M[
* @param hasNextPage f7Nmvla[q
* The hasNextPage to set. Ul]7IUzsu
*/ e8xq`:4Y
publicvoid setHasNextPage(boolean hasNextPage){ <%uEWb)
this.hasNextPage = hasNextPage; ?VE'!DW
} l_:P|
Nr>UZlU8
/** L{F]uz_[x
* @return jwE=
* Returns the hasPrePage. *.>@
*/ <zn)f@W
publicboolean getHasPrePage(){ Tt~[hC
h
return hasPrePage; QA0uT{x90
} +39uKOrZ
zM&ro,W
/** zqNzWX
* @param hasPrePage rY^uOrR>j*
* The hasPrePage to set. w$f_z*/
*/ HSG Ln906
publicvoid setHasPrePage(boolean hasPrePage){ H6 x
this.hasPrePage = hasPrePage; T&pCLvkz
} oydP}X
=&UE67eK,
/** JnK<:]LcK
* @return Returns the totalPage. ^" ?a)KC
*
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*/ )?#K0o[<
publicint getTotalPage(){ @hg[v`~
return totalPage; N^[
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} >VIFQ\
2ak]&ll+h
/** k
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* @param totalPage TU~y;:OJ
* The totalPage to set. mp$IhJ6#
*/ %+j/nA1%S
publicvoid setTotalPage(int totalPage){ N)Q_z9b=
this.totalPage = totalPage; v0 :n:q
} A9BoH[is7
qfJ2iE|o2.
} dyn)KDS
~%>i lWaHB
0$Rn|yqf%
~\NQkaBkY
|Vz)!M
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 ms}o[Z@n
\X*y~)+K`
个PageUtil,负责对Page对象进行构造: LZ_VLW9wE
java代码: ,S`n?.&& 7
(!{*@?S
U~ a\v8l~
/*Created on 2005-4-14*/ @Drl5C}+
package org.flyware.util.page; SQK82/
8ly)G
import org.apache.commons.logging.Log; !|4]V}JQ
import org.apache.commons.logging.LogFactory; 06AgY0\
gw,K*ph}q
/** >^g2Tg:
* @author Joa QEt"T7a[/
* (jU_lsG
*/ UwS7B~
publicclass PageUtil { )GG9[%H!
xgIb6<qwY
privatestaticfinal Log logger = LogFactory.getLog aIa<,
'12*'Q+{+
(PageUtil.class); RDDA^U7y#
uNuFD|aQ.
/** T=-UcF
* Use the origin page to create a new page y-.{){uaD
* @param page \v-I<"::
* @param totalRecords au50%sA~
* @return U'" #jT
*/ [#@lsI
publicstatic Page createPage(Page page, int qtAt=` s
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totalRecords){ 3h.,7,T
return createPage(page.getEveryPage(), y'^U4# (
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h
page.getCurrentPage(), totalRecords); L{jx'[C
} D
)`(b
&\6},JN
/** aeN #<M&$<
* the basic page utils not including exception 9Xg7=(#
FvVC 2Z
handler Lwi"K8.u
* @param everyPage NYHK>u/5c
* @param currentPage z~`X4Segw
* @param totalRecords 7$%G3Q|)L
* @return page $ dI
mA
*/ &UnhYG{A
publicstatic Page createPage(int everyPage, int d*Mqs}8
fNAW4I I}
currentPage, int totalRecords){ $[`rY D/.
everyPage = getEveryPage(everyPage); F%p DF\
currentPage = getCurrentPage(currentPage); ["&{^
int beginIndex = getBeginIndex(everyPage, }Em{?Hqy
00i MU
currentPage); Ddq*}Pf0K
int totalPage = getTotalPage(everyPage, J2x}@p
ZHZxr
totalRecords); , 2#Q>
boolean hasNextPage = hasNextPage(currentPage, dO z|CfUhI
E]n]_{BN]
totalPage); HEFgEYlO
boolean hasPrePage = hasPrePage(currentPage); T8g\_m
Ot47.z
returnnew Page(hasPrePage, hasNextPage, #lqH/>`>
everyPage, totalPage, SN{A@dyt
currentPage, '/UT0{2;rS
UVlB=
beginIndex); 7NT}
Zwf
} s|XWw<Sa
(Ox&B+\v+v
privatestaticint getEveryPage(int everyPage){ @:CM<+
return everyPage == 0 ? 10 : everyPage; cA4?[F
} .F@Lx45
en{p<]H
privatestaticint getCurrentPage(int currentPage){ :35h0;8+
return currentPage == 0 ? 1 : currentPage; n[!QrEeR},
} 4t =Kt
Pf4zjc
privatestaticint getBeginIndex(int everyPage, int v4Ag~Evcx
{:"<E?+
currentPage){ vzfMME17
return(currentPage - 1) * everyPage; 25`W"x_
} N}VoO0 I
)! rD&l$tE
privatestaticint getTotalPage(int everyPage, int u{=h%d/
\,/ozfJ7dT
totalRecords){ S) zw[m
int totalPage = 0; [I%eRo[
g,WTXRy
if(totalRecords % everyPage == 0) v7@"9Uw}
totalPage = totalRecords / everyPage; ] H;E(1iU
else @BnK C&{
totalPage = totalRecords / everyPage + 1 ; NVkYm+J#
6<\dQ+~
return totalPage; rMJ@oc
} ~.^:?yCA
m=E/um[D
privatestaticboolean hasPrePage(int currentPage){ :kI[Pf!z
return currentPage == 1 ? false : true; X4:84
} jbe:"Stw
P]^8Enp
privatestaticboolean hasNextPage(int currentPage, B0yGr\KJ
. mO8~Z
int totalPage){ }OcrA/
return currentPage == totalPage || totalPage == ?+=,t]`!m
p@Os
0 ? false : true; @Yb8CB
} l[5** ?#
<astIu Au
Z)xcxSo
} :
^}!"4{
Y{e,I-"{
: I";&7C
bt1bTo
K'8?%&IQ
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。 4IW90"uc
7lF;(l^Z>}
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 l<=k#d
N4VZl[7?
做法如下: X(d:!-_m *
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 /o$6"~t
xG
edY*[`
的信息,和一个结果集List: GBg
java代码: Iw?^
d=+zOF
YSB> WBS-<
/*Created on 2005-6-13*/ 9({ 9 r[U
package com.adt.bo; ;6 d-+(@
)N^fSenFBn
import java.util.List; {c?{M.R
^|h_[>
import org.flyware.util.page.Page; 2.);OFk+
7?k3jDK
/** W=S^t_F
* @author Joa ^oC>,%7
*/ qrOesSdc
publicclass Result { j3w~2q"r
~IO'"h'w
private Page page; U%1M?vT/
;A"i.:ZT
private List content; q2B'R
wH=7pS"s
/** b?Q$UMAbH
* The default constructor w(+L&IBC
*/ ?en-_'}~a
public Result(){ fOSJdX0e|Q
super(); mBrZ{hqS
} h8M}}
/;q3Q#
/** ;H%'K
* The constructor using fields ,{iMF
(Nj
* po]<sB
* @param page g] IPNW^n
* @param content i/8OC
*/ \N? lG q
public Result(Page page, List content){ >3 p8o@:
this.page = page; *hFJI9G
this.content = content; UDkH'x$=
} +('xzW
Xsb.xxK.
/** (Y&gse1}!
* @return Returns the content. ;gJAxVD<
*/ <|WXFjn
publicList getContent(){ 33}p02#
return content; 2}P{7flDY
} g(jn
/Cx
6eB~S)Ko
/** kJ.7C
* @return Returns the page. HCktgL:E=
*/ c0jTQMe4yl
public Page getPage(){ J~@W":v
return page; ;6]ag< Q
} bS|h~B]rd
S[8nGH#m
/** Wa?\W&
* @param content )!zg=}V
* The content to set. )WEOqaR]
*/ T9}dgf
public void setContent(List content){ vXdI)Sx[
this.content = content; A$P Oc<
} a(-t"OL\
6]!Jo)BF
/** N^[MeG,8
* @param page 5P);t9O6
* The page to set. Ho%%voJBS
*/ @O6
2}F
publicvoid setPage(Page page){ _!vuDv%
this.page = page; 9j;!4AJ1t
} 4
;6,h6a
} &ML-\aSal
s/;S2l$`
#cJ1Jj $
~-yq,x
z^KBV^n
2. 编写业务逻辑接口,并实现它(UserManager, n?^oQX}.\
l~1l~Gx_&n
UserManagerImpl) =jG."o
java代码: )ZZ6 (O
K[V#Pj9
gZz5P>^
/*Created on 2005-7-15*/ mX@xV*
package com.adt.service; gazX2P[D
FYg{IKg
import net.sf.hibernate.HibernateException; /5>A 2y
\3rgwbF
import org.flyware.util.page.Page; T%TO?[cN
oSR;Im<2
import com.adt.bo.Result; sw(|EZ7F
c/-'^+9
/** r/+~4W5
* @author Joa );p:[=$71
*/ @&Af[X4s
publicinterface UserManager { ){tTB
gHH[QLD=I
public Result listUser(Page page)throws IV`+B<3
)\izL]=!t
HibernateException; eN TKX
{I$zmVG
} ,G$<J0R1
%x^ U3"7
*M~BN}.
;T!ZO@1X
Z7MGBwP(
java代码: %F0.TR!!n
ge&!GO
v?q)E%5j
/*Created on 2005-7-15*/ p"Di;3!y!
package com.adt.service.impl; f F9=zrW
Is (
Ji
import java.util.List; ^"J)^3j<
{%Q+Pzl.
import net.sf.hibernate.HibernateException; 7a%)/)<D
/ \k\HK8
import org.flyware.util.page.Page; u-wj\BU
import org.flyware.util.page.PageUtil; ^K'XlM`a
H|d"45J_
import com.adt.bo.Result; )f`oCXh
import com.adt.dao.UserDAO; eyByAT~W,
import com.adt.exception.ObjectNotFoundException; 6l(HD([_p
import com.adt.service.UserManager; 0ol*!@?
_/}/1/y$Y
/** io$fL_R=
* @author Joa $viZ[Lu!m
*/ yzL6oU-{&
publicclass UserManagerImpl implements UserManager { u5P2*
f5t/=/6>F
private UserDAO userDAO; j@jUuYuDgl
0SDyE
/** @ql S #(
* @param userDAO The userDAO to set. HUGhz
*/ " ,45p@
publicvoid setUserDAO(UserDAO userDAO){ vSJ#
}&
this.userDAO = userDAO; ;c# jO:A5
} x?G"58
K|wB0TiXP
/* (non-Javadoc)
OGnuBK
* @see com.adt.service.UserManager#listUser %Wg8dy|
V.kf@
(org.flyware.util.page.Page) 1n>(CwLG"
*/ ^r
9
public Result listUser(Page page)throws EUuk%<q7C(
WQltUaF
HibernateException, ObjectNotFoundException { ggzcANCD<
int totalRecords = userDAO.getUserCount(); AKUmh
if(totalRecords == 0) c"S{5xh0&
throw new ObjectNotFoundException ZcrFzi
3m/XT"D
("userNotExist"); /,^AG2]( f
page = PageUtil.createPage(page, totalRecords); k :`yxxYIh
List users = userDAO.getUserByPage(page); .QM>^(o$Z
returnnew Result(page, users); }m.45n/
} GsNZr=;C
.vtV2lq
} Uf\U~wM<
$xq$
9at_F'>R
I73=PfS:m
2j-^F
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 T5+9#
w@hbY:Z9z
询,接下来编写UserDAO的代码: :Mnl 1;oh
3. UserDAO 和 UserDAOImpl: d`J~w/]
`\
java代码: X32{y973hT
9 EV. ![
bm-&H
/*Created on 2005-7-15*/ cFloaCz
package com.adt.dao; t'bhA20Z\
3V0^v
import java.util.List; ~y8KQ-1n"
eDS,}Z'
import org.flyware.util.page.Page; {*K7P> &
Nu7lPEM
import net.sf.hibernate.HibernateException; %"BJW
QJtO~~-
/** %@Nu{?I
* @author Joa <4%vl+qW
*/ _+}#
publicinterface UserDAO extends BaseDAO { wF$z ?L
o%[swoM@
publicList getUserByName(String name)throws Zd8`95
u\o~'Jz
HibernateException; {Z^q?~zC[
e#z#bz2<
publicint getUserCount()throws HibernateException; $'93:9tg
F0/!+ho
publicList getUserByPage(Page page)throws T3h 1eU
*w[0uQL5Z
HibernateException; NbUbLzE
Eanwk` Rx
} 6=g! Hs{
V ^hR%*i'
i&\cDQ 3
#=
@?)\~
k83S.*9Mx
java代码: L=V.@?
WXe]Q bg
Mk!bmFZOZ
/*Created on 2005-7-15*/ #]@|mf
q
package com.adt.dao.impl; zAH6SaI$
b
r\_
import java.util.List; IRT0
n|eM}ymF+
import org.flyware.util.page.Page; Nyl)B7/w
ecyN};V>
import net.sf.hibernate.HibernateException; o4nDjFhh
import net.sf.hibernate.Query; :*WiswMFm
w7b\?]}@
import com.adt.dao.UserDAO; WlmkM?@
;2l|0:
/** W?D-&X^ny
* @author Joa _[$,WuG1
*/ \"6?*L|]
public class UserDAOImpl extends BaseDAOHibernateImpl C!W0L`r
>- U+o.o
implements UserDAO { {fS~G2@1
Y |9
/* (non-Javadoc) 0?O$->t
* @see com.adt.dao.UserDAO#getUserByName b!`{fwV
%{&,5|8
(java.lang.String) Q+ZZwqyxD
*/ hd@jm^k
publicList getUserByName(String name)throws 3>mAZZL5[
j?1wP6/NP
HibernateException { 1x^Vv;K
String querySentence = "FROM user in class Q AX3*%h
heQyz|o
com.adt.po.User WHERE user.name=:name"; PP8627uP
Query query = getSession().createQuery %F13*hOu
8T88
(querySentence); -lm)xpp1
query.setParameter("name", name); hRZYvZ3
return query.list(); 8~y&" \
} ew<_2Xy"<
cc 0Tb
/* (non-Javadoc) 'PWA
* @see com.adt.dao.UserDAO#getUserCount() @S1Z"%S
*/ Ty} Y/jW
publicint getUserCount()throws HibernateException { =:'\wx
X
int count = 0; k{D0&
String querySentence = "SELECT count(*) FROM st)qw]Dn;Y
i@mS8%|l
user in class com.adt.po.User"; i(>
WeC+
Query query = getSession().createQuery 06]"{2
slAR<8
(querySentence); ]EdZ,`B4
count = ((Integer)query.iterate().next B_
bZa
&cwN&XBY
()).intValue(); `RXlqj#u
return count; k%VYAON
} 0X5b32
K
#}t\
/* (non-Javadoc) /h8100
* @see com.adt.dao.UserDAO#getUserByPage r+;k(HMY}[
w@pJ49
(org.flyware.util.page.Page) q7<=1r+
*/ '3?-o|v@D
publicList getUserByPage(Page page)throws k/1S7X[
hDXaCift
HibernateException { [9G=x[
String querySentence = "FROM user in class "RgP!
AkCy
C1
com.adt.po.User"; >R5A@0@d5
Query query = getSession().createQuery 8Oz9 UcG
6Ta+f3V
(querySentence); xxA^A
query.setFirstResult(page.getBeginIndex()) HvmE'O8
.setMaxResults(page.getEveryPage()); A?ho<@^
return query.list(); u~PZK.Uf0
} RAWzQE}
i|m8#*Hd
} 2#/23(Wc
#x`K4f)
|AS~sjWSJ
ae" o|Q
A]ZQ?-L/
至此,一个完整的分页程序完成。前台的只需要调用 LW k/h1
W8F@nY
userManager.listUser(page)即可得到一个Page对象和结果集对象 GL~
Wnt
-fp/3-
的综合体,而传入的参数page对象则可以由前台传入,如果用 o`G6!
-ijzo%&qA
webwork,甚至可以直接在配置文件中指定。 cbl>:ev1h
_D$1CaAYo
下面给出一个webwork调用示例: +;4;~>Y
java代码: e+)y6Q=
; tQ(l%!
;YSe:m*
/*Created on 2005-6-17*/ _>ZC;+c?
package com.adt.action.user; suE8"v!sk
[5ncBY*A7
import java.util.List;
i[I&m]N
Ve${g`7&
import org.apache.commons.logging.Log; a,(nf1@5
import org.apache.commons.logging.LogFactory; <@[;IX`YN
import org.flyware.util.page.Page; (V1;`sI8
)O5@R
import com.adt.bo.Result; (H"{r
import com.adt.service.UserService;
q*94vo-
import com.opensymphony.xwork.Action; $41<ldJ
"?<(-,T
/** /GX>L)
* @author Joa ^4NRmlb
*/ .)=*Yr M
publicclass ListUser implementsAction{ 9yaTDxB>
&nwS7n1eb
privatestaticfinal Log logger = LogFactory.getLog pU'${Z~b
M?DZShkV_
(ListUser.class); EV-sEl8ki
_>BYUPY
private UserService userService; bDudETl
v(GnG
private Page page; QO0@Ax\b
<-fvYer
privateList users; Hpa6;eT
w,up`W7,
/* K\xnQeS<W
* (non-Javadoc) QT
zN
* m.!LL]]
* @see com.opensymphony.xwork.Action#execute() bI|{TKKN&P
*/ *JfGGI_E
publicString execute()throwsException{ L>mM6$l
Result result = userService.listUser(page); v9FR
page = result.getPage(); ,]nRnI^
users = result.getContent(); v\CBw"
return SUCCESS; A FBH(ms't
} P3-O)m]jv
o.w/?
/** SP/b4
* @return Returns the page. y10W\beJ
*/ [PB73q8
public Page getPage(){ IZm6.F
return page; `"PHhCG+z
} ! L|l(<C
ju3@F8AI
/** 7)[2Ud8
* @return Returns the users. q,<l3r In
*/ [[]yQ
"
publicList getUsers(){ bCr
W'}:de
return users; ~k-'
} %rJDpB{
<bo^u w
/** #pgD-0_
* @param page .P7q)lj36h
* The page to set. '
`c \Dq
*/ f3qR7%X?
publicvoid setPage(Page page){ Er|&4-9
this.page = page; &bfM`h'
} qo7<g*kf~
Mpyza%zj
/** 5'+g[eNyBV
* @param users }No #_{
* The users to set. R.2i%cU
*/ n0gjcDHQ
publicvoid setUsers(List users){ -?:8sv*X
this.users = users; 1Az&BZU[
} qTRP2rH,L&
h.]^ o*DJ
/** SmD#hE[
* @param userService \)wVO*9*0
* The userService to set. v;5-1
*/ Q]GS#n
publicvoid setUserService(UserService userService){ d}fd^x/
this.userService = userService; Sz<:WY/(x
} Gey-8
} _<jU! R
,mvFeo;@f
H)E,([
g.Qn,l]X/p
6Iv};f"Y
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, a@&qdp
TCzlu#w
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 H7P}=YW".
)quQI)Ym
么只需要: HJJ)D E7;
java代码: G~.VW48{n
x=a#|]ngG
y7CXE6Y
<?xml version="1.0"?> COm^ti-p
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 3!@&7@p
@HB=hN
1.0//EN" "http://www.opensymphony.com/xwork/xwork- +PLJ
#K@!jh)y^
1.0.dtd"> LgX2KU"
8YE4ln
<xwork> YU0pWM
Iurz?dt4w
<package name="user" extends="webwork- 2-qWR<E
42hG}Gt
interceptors"> f%t
N2k
9[*P`*&
<!-- The default interceptor stack name 3hBYx@jTO
RrrlfF ms
--> 0Bp0ScE|FA
<default-interceptor-ref 7Dl^5q.|
'Kkp!eZQ~
name="myDefaultWebStack"/> I]5){Q"S
h(}#s1Fzq
<action name="listUser" s/~pr.>-l
.,(x7?
class="com.adt.action.user.ListUser"> P8=J0&5
<param y]obO|AH
?P9VdS1-
name="page.everyPage">10</param> r/0#D+A
<result
il{x?#Wrb
/8`9SS
name="success">/user/user_list.jsp</result> @>~S$nw/
</action> UHi^7jQ
P|?nx"c
</package> qFDy)4H)
#')]~Xa
</xwork> [:e>FXV
y6sY?uu
Yz0HBEA
-:L7iOzgD
PIFZ '6gn
R6>*n!*D@
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 &1=,?s]&
Fd80T6[
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 `LIlR8&@aX
WTt
/y\'6
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 d3?gh[$
1
rbc}e
>2}*L"YC
v[x 5@$
_h=h43'3
我写的一个用于分页的类,用了泛型了,hoho s:,fXg25J
#\Q)7pgi.
java代码: W0U|XX!&
F/A)2 H_
CnY dj~
package com.intokr.util; 4U)%JK.ta
$1)NYsSH/H
import java.util.List; Sqmjf@o$>
Y%]g,mG
/** 6~s{HI!
* 用于分页的类<br> c(?O E'
"Z
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ?&1%&?cg9
* aa!1w93?i
* @version 0.01
b^8"EBo
* @author cheng _Bn8i(
*/ k^k1>F}yx
public class Paginator<E> { (lit^v,9
privateint count = 0; // 总记录数 )F'hn+(B|G
privateint p = 1; // 页编号 7A<}JaE!,
privateint num = 20; // 每页的记录数 )0;O<G] d
privateList<E> results = null; // 结果 {EU]\Mp0j
c No)LF
/** ,<OS:]
* 结果总数 Wk-.dJ
*/ ND 8;1+3
publicint getCount(){ b_~KtMO
return count; 'e
x/IqbK
} T[0CD'|E
"6?Y$y/wm
publicvoid setCount(int count){ rHjR 4q
this.count = count; T z+Y_
} MI8c>5?
E*9W'e~=
/** =`gFwH<
* 本结果所在的页码,从1开始 `wLmGv+V
* 2V+[:>F
* @return Returns the pageNo. g@>y`AFnr
*/ CFY4PuI"!
publicint getP(){ /h&>tYVio
return p; ZhoB/TgdL
} wYHyVY2tj2
)GC[xo4bg
/** aO\@5i_r
* if(p<=0) p=1 dUceZmAl
* :J5CmU$
* @param p wLQM]$O
*/ (%M:=zm
publicvoid setP(int p){ +w@/$datI
if(p <= 0) ,(#n8|q4
p = 1; )7rMevF(xJ
this.p = p; VN@ZYSs
} 5hiuBf<
zjx'nK{eI
/** QO,ge<N+N
* 每页记录数量 .7#04_aP
*/ <*{(>
publicint getNum(){ -f(<2i
return num; gBd~:ZUa
} _Nbh Wv
dFpP_U
/** L w/ZKXDU2
* if(num<1) num=1 MS%h`Ypo
*/ 8ax3"G
publicvoid setNum(int num){ 'DH_ihZ
if(num < 1) n ZS*"O#L
num = 1; gi\UNT9x
this.num = num; K9'AYFse
} `&/ zOMp
C1~Ro9si
/** ,rQPs
* 获得总页数 MWc{7,
*/ _~ 7cn
publicint getPageNum(){ =j1Q5@vS
return(count - 1) / num + 1; 3+%L[fW`/
} |G-o&m"
'P-FeN^
/** RK=YFE 0
* 获得本页的开始编号,为 (p-1)*num+1 W&a<Q)o*I
*/ {D&:^f
publicint getStart(){ K:sC6|wG
return(p - 1) * num + 1; 1FC1*7A[
} !1?Nc}T0Q&
( KG>lTdN
/** s^AZ)k~J(
* @return Returns the results.
D'Sdz\:4
*/ .gHL(*1P
publicList<E> getResults(){ ;0\
return results; j2{ '!
} %OsV(7
BhJ~ jV"
public void setResults(List<E> results){ <^jW
this.results = results; *,__\/U98
} ~ +z'pK~c
I#hzU8Cc
public String toString(){ ;tLu
StringBuilder buff = new StringBuilder {mV,bg,}~
c7N`W}BZ
(); T\Q)"GB
buff.append("{"); X*C4NF0
buff.append("count:").append(count); F%QVn.
buff.append(",p:").append(p); Ndx ]5
buff.append(",nump:").append(num); 4;d9bd)A
buff.append(",results:").append .W%{j()op
|"a%S,I'
(results); o%tvwv
buff.append("}"); <El6?ml@
return buff.toString(); e c`3Qw
} G@QZmuj&KH
|+i?FYA\
} dmD':1
C_Z[ul
X\1'd,V