Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 wz.6du6-
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 /E5 5Pec
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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 ?Wt$6{)
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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 'ao"9-c
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。 Ch%m
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分页支持类: y>|{YWbp?
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java代码: adi[-L#
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package com.javaeye.common.util; DHT&,=
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import java.util.List; @b~fIW_3>
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publicclass PaginationSupport { (N=5.7"T
{ e5/+W
publicfinalstaticint PAGESIZE = 30; B8%{}[q
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privateint pageSize = PAGESIZE; j"@93D~
*[R
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privateList items; 0Ir<y
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privateint totalCount; ;6{@^
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privateint[] indexes = newint[0]; +@K09ge
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privateint startIndex = 0; 3y~r72J
t
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public PaginationSupport(List items, int <P;}unq.kw
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totalCount){ [wB9s{CX
setPageSize(PAGESIZE); ]UG*r%9
setTotalCount(totalCount); g}U3y'
setItems(items); la?Wnw
setStartIndex(0); t/PlcV_M"
} $4T2z-
p/
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public PaginationSupport(List items, int $<|lE/_]
?cEskafb>
totalCount, int startIndex){ 3#45m+D
setPageSize(PAGESIZE); e=QK}gzX
setTotalCount(totalCount); uH;-z_Wpn!
setItems(items); D'hW|
setStartIndex(startIndex); c9nH}/I_
} .ol'.t,S
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public PaginationSupport(List items, int UD y(v ]
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totalCount, int pageSize, int startIndex){ hw~a:kD
setPageSize(pageSize); yj(vkifEB
setTotalCount(totalCount); ^@_m "^C
setItems(items); [
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setStartIndex(startIndex); @ Ehn(}
} a`u
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'iY*6<xS<
publicList getItems(){ 34R!x6W0
return items; zPKr/
} e~T@~(fft
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publicvoid setItems(List items){ Mf#83<&K
this.items = items; ,*@AX>
} xlR2|4|8
6k/U3&R
publicint getPageSize(){ :ECi+DxBK
return pageSize; O!Z|r?
} 56Z\-=KAU
a3>zoN
publicvoid setPageSize(int pageSize){ GBC*>Y
this.pageSize = pageSize; N=)z
} io3yLIy,
L~^*u_U]
publicint getTotalCount(){ M-uMZQe
return totalCount; lRP1&FH0
} B,(Heg
cubk]~VD
publicvoid setTotalCount(int totalCount){ n!E2_
if(totalCount > 0){ T=YzJyQC)
this.totalCount = totalCount; {+g[l5CR[
int count = totalCount / =)OC|?9C\
.6pOvGKb
pageSize; JkA|Qdj~Mr
if(totalCount % pageSize > 0) $Vv}XMxw
count++; p=QYc)3F
indexes = newint[count]; <vbIp&
for(int i = 0; i < count; i++){ %AnW~v
indexes = pageSize * l~Lb!; ,dN
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i; 7a$G@
} {hO`6mr&t
}else{ t=#Pya
this.totalCount = 0; \ U-vI:J_
} il:nXpM!
} @oG)LT
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publicint[] getIndexes(){ H_IGFZ Ch
return indexes; )hj|{h7
} GW2')}g
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publicvoid setIndexes(int[] indexes){ YO:&;K%
this.indexes = indexes; jec:i-,
} `4CWE_k
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publicint getStartIndex(){ 7e&\{*
return startIndex; vVs#^"-nW
} /LQ:Sv7
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publicvoid setStartIndex(int startIndex){ zG
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if(totalCount <= 0) ?&l)W~S
this.startIndex = 0; 7nHTlI1b
elseif(startIndex >= totalCount) 4rU!4l
this.startIndex = indexes 4o9$bv
$'[q4 wo<
[indexes.length - 1]; 1{2eY%+C
elseif(startIndex < 0) !|m9|
this.startIndex = 0; ! ]Mc4!E
else{ \`,xgC9K
this.startIndex = indexes Ca $c;
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M
[startIndex / pageSize]; X^@[G8v%
} BZF,=v
} }1%r%TikY
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publicint getNextIndex(){ px9>:t[P
int nextIndex = getStartIndex() + %>XN%t'6aT
<5Mrp"C[i
pageSize; p#_[
if(nextIndex >= totalCount) /b.oEGqZX
return getStartIndex(); Y&'8VdW
else 8HoP(+?
return nextIndex; qvLDfN
} C 7nKk/r
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publicint getPreviousIndex(){ XSB8z
int previousIndex = getStartIndex() - ?(im+2
amB@N6*
pageSize; KC&`x|
if(previousIndex < 0) +|C[-W7Sw
return0; :J(sXKr[C
else @PcCiGZ
return previousIndex; nJVp.*S
} {(vOt '
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} GzdgL"M[
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抽象业务类 D&[Z;,CHMA
java代码: [{PqV):p
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/** i@$-0%,
* Created on 2005-7-12 *e<_; Kr?
*/ _F8T\f|
package com.javaeye.common.business; LC'2q*:'
( D}"&2
import java.io.Serializable; |@`"F5@,
import java.util.List; gGKKs&n7
: z~!p~
import org.hibernate.Criteria; w4:<fnOM
import org.hibernate.HibernateException; \X@IkL$r
import org.hibernate.Session; 56s*A*z$
;
import org.hibernate.criterion.DetachedCriteria; -fux2?8M
import org.hibernate.criterion.Projections; dokuyiN\
import Uh+jt,RB`
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org.springframework.orm.hibernate3.HibernateCallback; 5L&:_iQZy
import AA7#c7
aii'}c
org.springframework.orm.hibernate3.support.HibernateDaoS BQ#jwu0e
<"I?jgo
upport; VC=6uB
8!j=vCv
import com.javaeye.common.util.PaginationSupport; uJPH~mdW
b|E/LKa
public abstract class AbstractManager extends uiK:*[
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HibernateDaoSupport { B+D`\ Nl o
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privateboolean cacheQueries = false; n|]N7 b'
^W['A]l
privateString queryCacheRegion; MxN]7
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publicvoid setCacheQueries(boolean ~_}4jnC
J<_ 1z':W)
cacheQueries){ XZ@>]P
this.cacheQueries = cacheQueries; R`C.ha
} ^I./L)0=}
X RRJ)}P
publicvoid setQueryCacheRegion(String >q &L/N5
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queryCacheRegion){ f%1wMOzx
this.queryCacheRegion = $SF3odpt
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queryCacheRegion; hgj0tIi/
} k6g|7^es2
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publicvoid save(finalObject entity){ 2B'^`>+8S
getHibernateTemplate().save(entity); *dVD
} F`D9Zfd
Nz @8
publicvoid persist(finalObject entity){ !pS~'E&q
getHibernateTemplate().save(entity); v|To+P6b
}
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publicvoid update(finalObject entity){ ./)j5M
getHibernateTemplate().update(entity); J/gQQ.s
} (lb`#TTGx
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publicvoid delete(finalObject entity){
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getHibernateTemplate().delete(entity); |QqWVelc
} q @*UUj@
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publicObject load(finalClass entity, WnO DDr
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finalSerializable id){ U;>B7X;`E4
return getHibernateTemplate().load >";%2u1
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(entity, id); YRu%j4Tx
} ^~*8 @v""
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publicObject get(finalClass entity, 6DO0zNTY
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finalSerializable id){ I`#EhH
return getHibernateTemplate().get p1uN]T7>
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(entity, id); ~W/}:;
} Bx%=EN5.
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publicList findAll(finalClass entity){ <M`-`v6H
return getHibernateTemplate().find("from "j
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" + entity.getName()); =G[H,;W
} [5-!d!a|st
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publicList findByNamedQuery(finalString Q{`@
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namedQuery){ mf#fA2[
return getHibernateTemplate f!^)!~
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().findByNamedQuery(namedQuery); =>.DD<g"
} j@_nI~7f}
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publicList findByNamedQuery(finalString query, {Wr\DVp
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finalObject parameter){ B_b8r7Vn`
return getHibernateTemplate d[yrNB6|
r \9:<i8
().findByNamedQuery(query, parameter); i~(#S8U4d
} 69?I?,7
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publicList findByNamedQuery(finalString query, -aA<.+
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finalObject[] parameters){ ?!_u,sT
return getHibernateTemplate YlG;A\]k
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().findByNamedQuery(query, parameters); -uO%[/h;N
} iczs8gj*
z{@=_5;
publicList find(finalString query){ A"`L~|&
return getHibernateTemplate().find M3)v-"
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(query); h#v L5At
} 3s#|Y,{?6R
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publicList find(finalString query, finalObject W&WB@)ie
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parameter){ X"laZd947>
return getHibernateTemplate().find (=6P]~,
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(query, parameter); sn2r>m3
} yo'q[YtP'
5
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public PaginationSupport findPageByCriteria DI L)7K4
D[+|^,^>
(final DetachedCriteria detachedCriteria){ |>M-+@gj
return findPageByCriteria UU*0dSWr
tbL1g{Dz,
(detachedCriteria, PaginationSupport.PAGESIZE, 0); ks)fQFSbu
} aA7S'[NjB
Yjpb+}
public PaginationSupport findPageByCriteria ;|2Uf
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(final DetachedCriteria detachedCriteria, finalint YmdsI+DbIu
2K5}3<KD/
startIndex){ cq-e
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return findPageByCriteria *G8'Fjin'T
Qf/j:
(detachedCriteria, PaginationSupport.PAGESIZE, %?U"[F1
j*zB
{ s
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startIndex); fp`U?S6
} n5/ZJur
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public PaginationSupport findPageByCriteria @WMj^t1D+
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(final DetachedCriteria detachedCriteria, finalint 3 (Gygq#
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pageSize, O8!!UA8V
finalint startIndex){ l#mqV@?A~
return(PaginationSupport) JDIz28 Ww
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getHibernateTemplate().execute(new HibernateCallback(){ zS&7[:IRs'
publicObject doInHibernate =>E44v
(or =f`
(Session session)throws HibernateException { qpH j4
Criteria criteria = /&y,vkZTT
@^w!% ?J
detachedCriteria.getExecutableCriteria(session); Pc di
int totalCount = 8^&fZL',
! hOOpZf7
((Integer) criteria.setProjection(Projections.rowCount @ J?-a m>
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()).uniqueResult()).intValue(); RlG'|xaT
criteria.setProjection |:`?A3^m#
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(null); Y/QK+UMW*
List items =
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criteria.setFirstResult(startIndex).setMaxResults Pl`Bd0
W$x K^}
(pageSize).list(); n^g-`
PaginationSupport ps = d
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new PaginationSupport(items, totalCount, pageSize, {&6l\|
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<
startIndex); Th I
return ps; $D0)j(v
} 0B#rqTEKu
}, true); mP`,I"u
} #t5JUi%in*
<"j"h=tm}
public List findAllByCriteria(final _dH[STT
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DetachedCriteria detachedCriteria){ 7z0;FW3>9
return(List) getHibernateTemplate \`p |,j
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().execute(new HibernateCallback(){ Lx4H/[$6D
publicObject doInHibernate q[We][Nrzb
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(Session session)throws HibernateException { xLGTnMYd
Criteria criteria = exa}dh/uC
r(`8A:#d
detachedCriteria.getExecutableCriteria(session); \Ho#[k=y*/
return criteria.list(); <3J=;.\6
} -h.3M0
}, true); )aO!cQ{s
} ]J0Y^dM
o9(#KC?3
public int getCountByCriteria(final 0Zp<=\!;
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l
DetachedCriteria detachedCriteria){ ;9- 4J
Integer count = (Integer) eN7yjd'Y6
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getHibernateTemplate().execute(new HibernateCallback(){ ;_;H(%uY
publicObject doInHibernate r.W"@vc>
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(Session session)throws HibernateException { ~>wq;T:=
Criteria criteria = +&@l{x(,
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detachedCriteria.getExecutableCriteria(session); [eTck73
return ]mDsUZf<
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criteria.setProjection(Projections.rowCount O,z%7><
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()).uniqueResult(); z8rh*Rfxd
} 9/^Bj
}, true); [~rk`
return count.intValue(); pRyS8'
} G5Dji_ |
} YfYL?G
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N"Nd $4
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用户在web层构造查询条件detachedCriteria,和可选的 \6PIw-)
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 2QQYXJ^
^IegR>
PaginationSupport的实例ps。 d3q/mg 5a
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ps.getItems()得到已分页好的结果集 97=YFK~*
ps.getIndexes()得到分页索引的数组 mf_9O
ps.getTotalCount()得到总结果数 {;rpgc
ps.getStartIndex()当前分页索引 YuZ
ps.getNextIndex()下一页索引 GA@Q:n8UuR
ps.getPreviousIndex()上一页索引 %QcG^R
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 +_K;Pj]x
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 W}i$f -K
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一下代码重构了。 {xx;zjt%}}
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我把原本我的做法也提供出来供大家讨论吧: :JG}%
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首先,为了实现分页查询,我封装了一个Page类: Y:Tt$EQ
java代码:
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/*Created on 2005-4-14*/ ?ew]i'9(
package org.flyware.util.page; @g5]w&o_
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/** ;SP3nU))
* @author Joa ZQ8Aak
*
Y2$`o4*3
*/ 5rSth.&
publicclass Page { ~./u0E
I z@x^s
/** imply if the page has previous page */ FnU;n
privateboolean hasPrePage; nff ]Y$FB
q\=[v
/** imply if the page has next page */ 5~6y.S
privateboolean hasNextPage; *qOCo_=P8
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/** the number of every page */ h$h`XBVZe;
privateint everyPage; /]>{"sS(
I>zn$d*0
/** the total page number */ h^X.e[
privateint totalPage; l3$?eGGM
p;01a
/** the number of current page */ r>eXw5Pr7
privateint currentPage; XfDQx!gJ
<]`2H}*U'
/** the begin index of the records by the current ,6)y4=8 L
cjpl_}'L:
query */ spDRQ_qq
privateint beginIndex; !ry+ r!"
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0]W/88ut*u
/** The default constructor */ OH~qJ<
public Page(){ '0?E|B]Cp%
bHG>SW\]`?
} ?':'zT
t;6/bT-
/** construct the page by everyPage T}On:*&
* @param everyPage 0w&1wee(
* */ >U.uRq
public Page(int everyPage){ 8# AXK{
this.everyPage = everyPage; PUo&>
} .
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/** The whole constructor */ hY'%SV
p
public Page(boolean hasPrePage, boolean hasNextPage, ;sJ2K"c
<C xet~x
W%:zvqg
v
int everyPage, int totalPage, f>PU# D@B
int currentPage, int beginIndex){ 7 {<lH%Tn
this.hasPrePage = hasPrePage; P;[mw(
this.hasNextPage = hasNextPage; 4h(Hy&1C
this.everyPage = everyPage; hQeZI+
this.totalPage = totalPage; ?uv%E*TU
this.currentPage = currentPage; #$QY[rf=6
this.beginIndex = beginIndex; Qgi:q
} 9|DC<Zn&B#
IA!Kpg
W
/** EeJ]>
1
* @return lvffQ_t
* Returns the beginIndex. =Q/i<u
*/ =jh:0Q<43+
publicint getBeginIndex(){ upKrr
return beginIndex; #nz$RJsX
} 3~'F^=T.Y
XCoOs<O:@
/** &GAx*.L
* @param beginIndex <Z[R08 k
* The beginIndex to set. 4[wP$
*/ :r=_\?
publicvoid setBeginIndex(int beginIndex){ 'Mtu-\
this.beginIndex = beginIndex; f{oWd]eAhb
} 9NAlgET
s q$|Pad[
/** Uk4">]oct
* @return 8&bj7w,K
* Returns the currentPage. #U6qM(J
*/ mYvm_t9
publicint getCurrentPage(){ <hdCO<
0(
return currentPage; `$HO`d@0*R
} %cL:*D4oz
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/** I&c#U+-A'
* @param currentPage Y#,MFEd
* The currentPage to set. ,vj^AXU
*/ ){~.jP=-#
publicvoid setCurrentPage(int currentPage){ 4YC`dpO'
this.currentPage = currentPage; xOlkG*3c
} g11K?3*%Q
g(^l>niF:
/** =\.|'
* @return w8Yff[o
* Returns the everyPage. |Sq>uC)
*/ $G[##j2
publicint getEveryPage(){ he #iWD'
return everyPage; C/=ZNl9"fn
} J^cDa|j
I(SE)%!%S
/** |)?T([
* @param everyPage U$}]zaB
* The everyPage to set. th{h)( +H
*/ Yaqim<j
publicvoid setEveryPage(int everyPage){ fz*6 B NJ
this.everyPage = everyPage; "-sz7}Mb
} 3 a`-_<
TEtZPGFl
/** B=7L+6
* @return WD:5C3;
* Returns the hasNextPage. 9 )qx0
*/ V'B 6C#jT
publicboolean getHasNextPage(){ FgxQ}VvlH
return hasNextPage; 0Qz
\"gr
} p*Cbe\
v*pVcBY>
/** 9viC3bj. o
* @param hasNextPage hpU7
* The hasNextPage to set. ~JJv 2
*/ *zcH3a,9"x
publicvoid setHasNextPage(boolean hasNextPage){ `/O_6PQ}
this.hasNextPage = hasNextPage; tx.sUu6
} o<y7Ut
'4iu0ie>D
/** Jx]`!dP3
* @return U\N`[k.F
* Returns the hasPrePage. bZ)Jgz
*/ ;FUd.vg{
publicboolean getHasPrePage(){ n"JrjvS
return hasPrePage; Kfh"XpWc$
} 6 S8#[b
z3,z&Ra
/** (Jm_2CN7X
* @param hasPrePage E+gUzz5
* The hasPrePage to set. B^
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*/ P06K0Fxf
publicvoid setHasPrePage(boolean hasPrePage){ 1<*-,f
this.hasPrePage = hasPrePage; fXN;N&I
} Xs`/q}R
dFlx6H+R!0
/** YeQX13C"Z
* @return Returns the totalPage. &^Io\
* t0Uax-E(
*/ ][Kj^7/
publicint getTotalPage(){ pVr,WTr6E
return totalPage; fqi584
} :Vg,[\I{
+J2=\YO
/** {r"HR%*u
* @param totalPage Cpl\}Qn
* The totalPage to set. lH[N*9G(
*/ e>[QF+e)y
publicvoid setTotalPage(int totalPage){ %}@^[E)
this.totalPage = totalPage; &\A$Rj)
} F[lHG,g-
?w.Yx$Z"
} : v]< h
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_$\T;m>'A
Ky+TgR
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 P_9O8"W
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个PageUtil,负责对Page对象进行构造: ~o+u: ]
java代码: j=7 ]"%
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/)|*Vzu
/*Created on 2005-4-14*/ _M?:N:e
package org.flyware.util.page; "|hmiMdGB
2`;
0y M
import org.apache.commons.logging.Log; 7w9) ^
import org.apache.commons.logging.LogFactory; b3Do{1BV
*@yYqI<1a
/** Kh27[@s
* @author Joa PpbW+}aCF
* ZEB1()GB
*/ IgVxWh#
publicclass PageUtil { ^OUkFH;dG?
Vry#
privatestaticfinal Log logger = LogFactory.getLog `=oN &!
R{.ku!w
(PageUtil.class); r8mE
JI.ad_IR
/** 9%4rO\q
* Use the origin page to create a new page e|`&K"fnq
* @param page Lm8cY
* @param totalRecords ^uYxeQY[
* @return bH&[O`vf
*/
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publicstatic Page createPage(Page page, int )yjHABGJ
IuPwFf)
totalRecords){ ztf (.~
return createPage(page.getEveryPage(), es.`:^A
2lQ'rnqS)
page.getCurrentPage(), totalRecords); MVV<&jho{^
} Zcc6E2
xX}vxhN
/** IKpNc+;p
* the basic page utils not including exception 67d0JQTu
-E.EI@"
handler AE@*#47
* @param everyPage =_,w<
* @param currentPage hF6EOCY6D
* @param totalRecords )4j#gHN\
* @return page &0M^UvO
*/ 98x(2fCvF(
publicstatic Page createPage(int everyPage, int WFtxEIrl3j
GX\/2P7CZ
currentPage, int totalRecords){ " 4s,a
everyPage = getEveryPage(everyPage); oSxHTbp?
currentPage = getCurrentPage(currentPage); .a$][Jny
int beginIndex = getBeginIndex(everyPage, Jyvc(~x
y>|7'M*+
currentPage); &}rh+z
int totalPage = getTotalPage(everyPage, r3#H]c
vQztD_bX%
totalRecords); `6UW?1_Z5
boolean hasNextPage = hasNextPage(currentPage, 9hcZbM]
uRJLSt9m
totalPage); f ^z7K
boolean hasPrePage = hasPrePage(currentPage); R7+k=DI
!
XA07O[@
returnnew Page(hasPrePage, hasNextPage, e%"L79Of6)
everyPage, totalPage, ceAK;v
o
currentPage, lv,<[Hw1
<jfi"SJu
beginIndex); 2Ui)'0
} {4UlJ,Z.n
"#(]{MY
privatestaticint getEveryPage(int everyPage){ IS"UBJ6p
return everyPage == 0 ? 10 : everyPage; Yk[yG;W
} 9;kWuP>k4u
'R= r9_%
privatestaticint getCurrentPage(int currentPage){ (eHvp
return currentPage == 0 ? 1 : currentPage; <Cm:4)~
} )t0t*xu#
jRzR`>5
privatestaticint getBeginIndex(int everyPage, int .BZw7
YV
l1a=r:WhH
currentPage){ ~,.Agx
return(currentPage - 1) * everyPage; TR|G4l?
} ^KmyB6Yg
BT>8
privatestaticint getTotalPage(int everyPage, int Z3=t"
Es1Yx\/:
totalRecords){ >AV?g8B;
int totalPage = 0; zS]Yd9;X1
_<&IpT{w+
if(totalRecords % everyPage == 0) KD=T04v
totalPage = totalRecords / everyPage; J %URg=r
else u
JGYXlLE
totalPage = totalRecords / everyPage + 1 ; }Z"<KF
^2XoYgv
return totalPage; &H<-joZ)Z\
} ewD61Y8-
"C%;9_ig$
privatestaticboolean hasPrePage(int currentPage){ FX 0^I 0
return currentPage == 1 ? false : true;
n~k;9`
} (yn!~El3
L3'o2@$
privatestaticboolean hasNextPage(int currentPage, IKH#[jW'IB
5Tkh6 s
int totalPage){ =]E;wWC
return currentPage == totalPage || totalPage == qVx0VR1:
8g^OXZ
0 ? false : true; c(i-~_
} (WX,&`a<$
dyD=R
I"y=A7Nq
} OiZPL" Q(K
t
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hBOI:4u[
&K|<7Efx
oe# :EfT
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。 8 }nA8 J
}r9f}yX9Q
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 fo^M`a!va0
esWgYAc3{
做法如下: x/R|i%u-s
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象
JstX# z
>n{(2bcFs
的信息,和一个结果集List: 9co1+y=i{
java代码: k5P&F
T[*=7jnJQ
X2/`EN\
/*Created on 2005-6-13*/ s+$l.aIO!
package com.adt.bo; %HpTQ
fOF02WP^
import java.util.List; 1Hp0,R}
#92:h6
import org.flyware.util.page.Page; 1ki##v[ W8
8J7xs6@
/** ]@)X3}"!
* @author Joa W:ih#YW_F
*/ %DbL|;z1
publicclass Result { y!h$Z6.
g< M\zD
private Page page; l!EfvqWX
,0[bzk
private List content; ==l p\
YR=<xn;m.
/** cL7je
* The default constructor p9y
"0A|
*/ {|O8)bW'
public Result(){ &NL=Bd
super(); pdngM8n
} rc<^6HqD
dc|"34;^"
/** T4F}MVK
* The constructor using fields { %vX/Ek
* ;lB%N
t<,
* @param page &Ru|L.G`
* @param content 4t|ril``]
*/ Eo!1
WRruF
public Result(Page page, List content){ a]Bm0gdrO
this.page = page; tK`sVsm>
this.content = content; XTUxMdN
} "@;q! B.qo
O&!+ni
/** (dLt$<F
* @return Returns the content. c 5+oP j
*/ pej/9{*xg(
publicList getContent(){ b54<1\&
return content; -SGR)
} HpC|dtro
Ks(+['*S
/** *RD9gIze
* @return Returns the page. dP=1*
*/ _>9|"seR
public Page getPage(){ DGz'Dn
return page; .9#4qoM'
} )O#]Wvr
4L 85~l
/** mVcpYyD|k
* @param content b'p bf
* The content to set. RFU(wek
*/ YR@@:n'TP
public void setContent(List content){ 1Thr74M
this.content = content; :z_D?UQ
} EW%%W6O6
s/Fc7V!;
/** Z,M?!vK
* @param page ;cH|9m:Y
* The page to set. +y! dU{L^
*/ iW(HOsA
publicvoid setPage(Page page){ sU^2I v\%
this.page = page; M`*B/Fh2
} N6S0(%
} s4<[f%^
9x0B9&
3ZGU?Z;R
dQVV0)z
<*3{Twa1T
2. 编写业务逻辑接口,并实现它(UserManager, MUh)
zW,m3~XX:
UserManagerImpl) (C={/waJ
java代码: OB)Vk
qAUqlSP5
^0_ *AwIcN
/*Created on 2005-7-15*/ 'S@%
package com.adt.service; >"q0"zrN,
rk*Igqf
import net.sf.hibernate.HibernateException; a,b;H(em
LzB)o\a
import org.flyware.util.page.Page; [yM{A<\L
Y5&Jgn.l
import com.adt.bo.Result; B$1nq#@
0APwk
}
/** )tl=tH/$
* @author Joa TS^(<+'
*/ }jBr[S5
publicinterface UserManager {
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#Z;ziM:
public Result listUser(Page page)throws A8&yB;T$y
-sm{Hpf_b
HibernateException; $9Hod-Z1
.\= GfF'
} 9:4PJ%R9
=B4U~|k
{(]B{n
s
Z(LT'}
2hdi)C,7Y
java代码: O Ul+es
M,"4r^%k
9a 9<I
/*Created on 2005-7-15*/ eUPG){"
package com.adt.service.impl; '31pb9@fH
jv>l6)
import java.util.List; E@^`B9;Q7
o\vIYQ
import net.sf.hibernate.HibernateException; U~-Z`_@^-
rQg7r>%Q
import org.flyware.util.page.Page; A(X~pP&oF
import org.flyware.util.page.PageUtil; .",E}3zn
an={h,
import com.adt.bo.Result; 1v!Xx+}
import com.adt.dao.UserDAO; +6@".<
import com.adt.exception.ObjectNotFoundException; I~y[8
import com.adt.service.UserManager; 3C 84b/A
${0+LhST
/** ftq&<8
* @author Joa y;<^[
*/ XmXp0b7
publicclass UserManagerImpl implements UserManager { ,u^i0uOg
zD}dvI}
private UserDAO userDAO; "P\k_-a'
Y,I0o{,g
/** Q<B=m6~
* @param userDAO The userDAO to set. P$S>=*`n
U
*/ {c`kC]9
publicvoid setUserDAO(UserDAO userDAO){ }C!N$8d,
this.userDAO = userDAO; lfG]^id'
} tX$%*Uy
#X'!wr|-
/* (non-Javadoc) P0uUVU=B|
* @see com.adt.service.UserManager#listUser Sq8 `)$\
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(org.flyware.util.page.Page) zm4Okg)w@
*/ li;Np5P
public Result listUser(Page page)throws +RQlMAB
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HibernateException, ObjectNotFoundException { Bi/=cI
int totalRecords = userDAO.getUserCount(); 4]0|fi3}>
if(totalRecords == 0) 5jD2%"YUV
throw new ObjectNotFoundException 9$8B)x
+:pjQ1LsJ
("userNotExist"); ~f0Bu:A)
page = PageUtil.createPage(page, totalRecords); NF&R}7L
List users = userDAO.getUserByPage(page); gd^1c}UZX
returnnew Result(page, users); )pLde_ k
} Zc(uK{3W-
wG6>.`:
} hd1(q33
hE0
p>R8
&dp<i[ec^
U1G"T(;s:
u!?cKZw
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 :pj#t$:!
\E1[ /
询,接下来编写UserDAO的代码: 7y.$'<
3. UserDAO 和 UserDAOImpl: ce!0Ws+
java代码: wZ/Zc}
.
zY_BnJ^
E7@0,9AU
/*Created on 2005-7-15*/ { \9vW; '
package com.adt.dao; ,0O9!^
,<s'/8Ik
import java.util.List; [t/7hx"2t
AeR3wua
import org.flyware.util.page.Page; ce-5XqzY@
|1C=Ow*"
import net.sf.hibernate.HibernateException; VCfa<hn
{eA0I\c(C
/** C"no>A^
* @author Joa 4%>iIPXi.(
*/ :"5'l>la
publicinterface UserDAO extends BaseDAO { ZZk6 @C
B
3<T#
publicList getUserByName(String name)throws p+#$S4V
dlkxA^
HibernateException; ?
hU0S
`7$0H]*6
publicint getUserCount()throws HibernateException; {#"[h1
k)j,~JH
publicList getUserByPage(Page page)throws fvnj:3RK
#vCtH2
HibernateException; :MPWf4K2s
<yzgZXxIaS
} gE2k]`[j]
YLs%u=e($
:4RD.l
N T+%u-
|35"V3bs
java代码: aoj6/
Ve\^(9n
2VObj7F
/*Created on 2005-7-15*/ 46`(u"RP
package com.adt.dao.impl; ;LEO+,6
{ ]Tb
import java.util.List; B>sSl1opI
0\XG;KA
import org.flyware.util.page.Page; A'Q=DoE
Mg3>/!
import net.sf.hibernate.HibernateException; 2;X{ZLo
import net.sf.hibernate.Query; p2T<nP<Pt
5n,?&+*L
import com.adt.dao.UserDAO; USBU?WDt
#nG?}*#
/** =(\
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0-[
* @author Joa 2MS-e}mi
*/ vzDoF0Ts*p
public class UserDAOImpl extends BaseDAOHibernateImpl AA$+ayzx9{
nGb%mlb
implements UserDAO { h# R;'9*V
W
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/* (non-Javadoc) ^APPWQUl
* @see com.adt.dao.UserDAO#getUserByName \$; Q3t3
@hC ,J
(java.lang.String) M.B0)
*/ '?7?"v
publicList getUserByName(String name)throws rjsqXo:9
8K(3{\J[V
HibernateException { 7i(U?\A;.
String querySentence = "FROM user in class EVs.'Xg<
v&}+ps_W
com.adt.po.User WHERE user.name=:name"; ,au-g)IFZ
Query query = getSession().createQuery AcC'hr.N+
I!\;NVhv
(querySentence); |ci1P[y
query.setParameter("name", name); 3O % u?
return query.list(); um.s:vj$
} .CU~wB@h
7O)j]eeoL
/* (non-Javadoc) [fVtQ@-S!
* @see com.adt.dao.UserDAO#getUserCount() fd Vye|%
*/ PeCU V6
publicint getUserCount()throws HibernateException { WGy3SV )
int count = 0; lM0`yh
String querySentence = "SELECT count(*) FROM 08*O|Ym,
\~j6}4XS1.
user in class com.adt.po.User"; MZ9{*y[z
Query query = getSession().createQuery >wsS75n1
T\}?
(querySentence); t4HDt\}&k~
count = ((Integer)query.iterate().next St9+/Md=jQ
&dA{ <.
()).intValue(); [Ol}GvzJ7
return count; #fT1\1[]
} ~r(/)w\
/eFudMl
/* (non-Javadoc) 2RW^Nqc9
* @see com.adt.dao.UserDAO#getUserByPage Y<1]{4Wt
@C\>P49
(org.flyware.util.page.Page) 47]?7GU,
*/ fg[]>:ZT.
publicList getUserByPage(Page page)throws SU.9;I
!
`8 Q3=^)3
HibernateException { X MkyX&y
String querySentence = "FROM user in class sf""]c$
m5Q?g8
com.adt.po.User"; /%O+]#$`0
Query query = getSession().createQuery ^uG^XY&ItC
Z?XgY\(a(Q
(querySentence); k2]Q~
query.setFirstResult(page.getBeginIndex()) 3RYg-$NK[
.setMaxResults(page.getEveryPage()); Xgq-r $O2X
return query.list(); z>n<+tso
} ZAKNyA2
ykq9]Xqhv
} >$^v@jf
=^nb-9.
{R5{v6m_
s>d /9 b
X9:4oMux7
至此,一个完整的分页程序完成。前台的只需要调用 g7>p,
pxj}%LH
userManager.listUser(page)即可得到一个Page对象和结果集对象 s#f6qj
I@sXmC2$\
的综合体,而传入的参数page对象则可以由前台传入,如果用 CqF=5z:A
]J`yh$a
webwork,甚至可以直接在配置文件中指定。 t,CC~
<OYy;s
下面给出一个webwork调用示例: x{=@~c%eh
java代码: DM*GvBdR
nMz~.^Q-
| dLA D4%
/*Created on 2005-6-17*/ _1<zpHp
package com.adt.action.user; ^F}HWpF_
I $5*Puy#
import java.util.List; >pS@;t'
vbol70
import org.apache.commons.logging.Log; ,[ogh
import org.apache.commons.logging.LogFactory; Y(:.f-Du
import org.flyware.util.page.Page; O(P
,!
47(/K2
import com.adt.bo.Result; hvc%6A\nm
import com.adt.service.UserService; naQ0TN,
import com.opensymphony.xwork.Action; *{/L7])gm
/Ah|Po
/** ,{KjVv<
* @author Joa
*jAw
*/ vocXk_
publicclass ListUser implementsAction{ {{3n">s}:
fJjtrvNy)
privatestaticfinal Log logger = LogFactory.getLog bU(H2Fv
>_ )~"Ra
(ListUser.class); d&!ZCq#_e
]GSs{'UhB
private UserService userService; >Ei-Spy>Xl
i/Nd
private Page page; 6f$h1$$)^
k1EAmA
l
privateList users; <%@S-+D`]
~-1!?t/%
/* d;Uzl1;
* (non-Javadoc) pO2Y'1*
* aP%&-W$D|
* @see com.opensymphony.xwork.Action#execute() ZO`{t1
*/ 5LPyPL L
publicString execute()throwsException{ |~6X:
M61
Result result = userService.listUser(page); N*dO'ol
page = result.getPage(); cqr4P`Oj
users = result.getContent(); EPY64{
return SUCCESS; dWg09 sx
} .6@qU}
qTGEi
/** 6"
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* @return Returns the page. zsQhydTR
*/ 7DG{|%\HF
public Page getPage(){
"F,d}3}
return page; ( k@%04c
} w]BZgF.
%B;e7
UJ
/** ywPFL/@
* @return Returns the users. OS
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*/ %*>ee[^L ,
publicList getUsers(){ \~3g*V
return users; G! y~Y]e
} kQr\ktN\
K):MT[/"
/** SBj9sFZ
* @param page U\_-GS;1
* The page to set. =h`yc$
A(2
*/ $m.e}`7SF!
publicvoid setPage(Page page){ c<'Pt4LY
this.page = page; Z+zx*(X
} >bKN$,Qen
ql|ksios
/** GsYi/Z
* @param users 7y4!K$c$
* The users to set. m{U+aqAQK
*/ JWu^7}@~=
publicvoid setUsers(List users){ ^>g7Kg"0
this.users = users; |{KZ<
} ,ZVC@P,L
-I#]#i@gX
/** LD'eq\vO
* @param userService {x$h K98
* The userService to set. Dm,*G`Js
*/ -^y$RJC
publicvoid setUserService(UserService userService){ YQB. 3
this.userService = userService; X,zqI
} 8x`?Yc
} Zcaec#
-SZW[T<N"
yJt0KUw@!
a<Ru )Q?=
LX4*3c|i,
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, I?).D?o
C
*\
=Q
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 Ab]`*h\U
wKjL}1.k
么只需要: MjO.s+I
java代码: rtl|zCst
PMDx5-{A/t
]F,mj-?4x
<?xml version="1.0"?> l s(lL\
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ~*Fbs! ;,
CS:"F) at
1.0//EN" "http://www.opensymphony.com/xwork/xwork- cU,]^/0Y
rt\i@}
1.0.dtd"> A4}6hG#
hFDY2Cp]D
<xwork> $'SWH+G
$6BD6\@
<package name="user" extends="webwork- '.n0[2>
Gw"H#9J}
T
interceptors"> ,ux?wa+
!nQ!J+ g
<!-- The default interceptor stack name 1-@[th
9-<EeV_/
--> }Q 7~tu
<default-interceptor-ref Et\z^y
e 1W9Z $m
name="myDefaultWebStack"/> AE:IXP|c
g~5$X{
<action name="listUser" 93zoJiLRf
=WaZy>n}7
class="com.adt.action.user.ListUser"> ]fN\LY6p
<param
5jj<sj!S
dtK[H+
name="page.everyPage">10</param> pi>,>-Z
<result t)Iu\bP
'\I.P
name="success">/user/user_list.jsp</result> p'lL2n$E
</action> !,rp|
, _K /e
</package> wnaT~r@U'
[25[c><:w"
</xwork> /8S g<
@M[t|
(Rqn)<<2
7*bUy)UZ
dgLE/r?
oDY
$F%
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 d ] J5c
z(sfX}%
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 C;#-2^h
alQMPQVin
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 VdrqbZ
+|#lUXC
!d@q T.
),#%jc2_^
h J*2q"
我写的一个用于分页的类,用了泛型了,hoho Lh0qB)>
X.u&4SH
java代码: s?=v@|vz)
;pK/t=$
D4e*Wwk
package com.intokr.util; U)Cv_qe
9M3XHj
import java.util.List; F iZe4{(p
-YF]k}|
/** ,>6s~'
* 用于分页的类<br> ^_6.*Mvx
* 可以用于传递查询的结果也可以用于传送查询的参数<br> sEpY&6*
* Eiqx1ZM
* @version 0.01 OhC%5=a7
* @author cheng ]L/h,bVI1
*/ huj 6Ysr
public class Paginator<E> { "~
1:7{k
privateint count = 0; // 总记录数 'CE3
|x\%K
privateint p = 1; // 页编号 `Sh#>
Jp
privateint num = 20; // 每页的记录数 *VJT]^_
privateList<E> results = null; // 结果 c{YBCWA
aRPpDSR?l
/** W(^R-&av
* 结果总数 FsZW,
*/ #G'Y2l
publicint getCount(){ qmNg Ez%
return count; ,(h:0L2v7d
} 8ZY F%
KI* erK
[d
publicvoid setCount(int count){ y|sU-O2}Dl
this.count = count; U ?vG?{A
} BCH{0w^D
}.j<kmd
/** b`?$;5
* 本结果所在的页码,从1开始 oMM+af
* ZCdlTdY
* @return Returns the pageNo. i98>=y~
*/ zcF`Z{&+
publicint getP(){ 6[r-8_
return p; x+? P/Ckg
} Mf7Z5
={HYwP;
/** Lt\Wz'6Y
* if(p<=0) p=1 l~|x*JTq
* L'=mDb
* @param p 1}O&q6\"J
*/ *fz]Q>2g a
publicvoid setP(int p){ )U6-&-07
if(p <= 0) X~m*` UH
p = 1; 1y\-Iz^
this.p = p; *>m,7} L
} TR@*tfS
;ps0wswX
/** 6N7^`ghTf
* 每页记录数量 Ie12d@
*/ dvPK5+0W?
publicint getNum(){ 2n/cqK
return num; 3aD\J_
} 0l.\KF
'/2u^&W
/** pDw^~5P
* if(num<1) num=1 BKd03s=
*/ X\\c=[#8-
publicvoid setNum(int num){ 0keqtr
if(num < 1) 28/At
num = 1; hUL5V1-j
this.num = num; /UwB6s(
} O,$
?Pj6
bl/tl_.p00
/** ;nzzt~aCC
* 获得总页数 PWavq?SR
*/ s{QS2G$5
publicint getPageNum(){ %Z:07|57I[
return(count - 1) / num + 1; S,Y\ox-
} =g]Ln)jc
<B+xE?v4
/** Z@Tb3N/[
* 获得本页的开始编号,为 (p-1)*num+1 p#k>BHgnF
*/ gb_r <j:w
publicint getStart(){ |.asg
return(p - 1) * num + 1; o@o0V
} 8`I/\8;H'p
`~~.0QC
/** .ty^ k@J|]
* @return Returns the results. U};~ff+
*/ "Uk "
publicList<E> getResults(){ F.N4Q'2Z
return results; ZvQ~K(3
}
Iu3*`H
F<W`zQ46
public void setResults(List<E> results){ #b^x! lR
this.results = results; e!eUgD
} d]fo>[%Xr
Sj,>O:p
public String toString(){ HU~,_m
StringBuilder buff = new StringBuilder ap
5D6y+
~s$
jiA1
(); JPsR7f
buff.append("{"); IJ#G/<ZJZ
buff.append("count:").append(count); _^Ds[VAgA
buff.append(",p:").append(p); )&jE<C0
buff.append(",nump:").append(num); { \r1A
buff.append(",results:").append 0=WZ 8|R
Q!%C:b
(results); I;=HXL
buff.append("}"); 8 !{;yz
return buff.toString(); 5.]eF$x2
} e9F\U
|i/Iv
} =|Q7k +b
RV%aFI )
~|FKl%