Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 bE" J&;|
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 O9:J
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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 z2SR/[I?
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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 Jv D`RUh
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分页支持类: fXAD~7T*s
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java代码: *
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package com.javaeye.common.util; $)7Af6xD
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import java.util.List; ,jMV
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publicclass PaginationSupport { E>qe hs,g
cONfHl{
publicfinalstaticint PAGESIZE = 30; `aaT
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privateint pageSize = PAGESIZE; i-&"1D[&
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privateList items; DZX4c 2J
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privateint totalCount; S3YAc4
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privateint[] indexes = newint[0]; %l)~C%T
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privateint startIndex = 0; 9!Vp-bo
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public PaginationSupport(List items, int ~Nl`Zmn(A|
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totalCount){ @#| R{5=+
setPageSize(PAGESIZE); F2["Ak NM
setTotalCount(totalCount); "4i_}
setItems(items); (OHd} YQ
setStartIndex(0); PX,fg5s\b
} JT 5+d ,
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public PaginationSupport(List items, int o`[X _
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totalCount, int startIndex){ XBHv V05mv
setPageSize(PAGESIZE); Uc|MfxsL
setTotalCount(totalCount); 7=]Y7"XCf
setItems(items); +@K8:}lOW
setStartIndex(startIndex); Z!qF0UDj
} P+;@?ofB
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public PaginationSupport(List items, int M.}QXta
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totalCount, int pageSize, int startIndex){ 74*iF'f?c
setPageSize(pageSize); @EcY&mP)
setTotalCount(totalCount); BGVy
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setItems(items); &8 4Izs/[
setStartIndex(startIndex); QjwCY=PK!
} {m<!-B95
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publicList getItems(){ cOEzS
return items; j~rarR@NB)
} }sS1p6z
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publicvoid setItems(List items){ f= l*+QY8f
this.items = items; _fANl}Mf:
} J*O$)K%Hx
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publicint getPageSize(){ b1qli5
return pageSize; jRIm_)
} p h=[|P)
;^:$O6J7T~
publicvoid setPageSize(int pageSize){ hk1jxnQh
this.pageSize = pageSize; Mt`XHXTp
} #n}n
%
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publicint getTotalCount(){ Li\BRlebR{
return totalCount; 1_.#'U>
} MOW {g\{\
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publicvoid setTotalCount(int totalCount){ - dt<w;>W
if(totalCount > 0){ oJTsrc_-
this.totalCount = totalCount; Q CB~x2C
int count = totalCount / ~j2=hkS
H@WQO]PA
pageSize; QabYkL5@
if(totalCount % pageSize > 0) abM4G
count++; Y_<(~eN`
indexes = newint[count]; )z?Kq0
for(int i = 0; i < count; i++){ T3
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indexes = pageSize * mF !=H%
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i; 3
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} Aw *:5 I[
}else{ k)R>5?_
this.totalCount = 0; c F(]`49(
} JP<Z3
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} ~0>{PD$@
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publicint[] getIndexes(){ >h
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return indexes;
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} m=<;)
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publicvoid setIndexes(int[] indexes){ n`hes_{,g
this.indexes = indexes; s~6irf/
} 5K*-)F
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publicint getStartIndex(){ ?RD)a`y51
return startIndex; e?D,=A4mV"
} %C[ ;&
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publicvoid setStartIndex(int startIndex){ ai,Mez
if(totalCount <= 0) ]jzINaMav
this.startIndex = 0; $0zH2W
elseif(startIndex >= totalCount) gZs8BKO
this.startIndex = indexes (7rG~d1iS
S&P5##.u`
[indexes.length - 1]; 1`_i%R^
elseif(startIndex < 0) c};Qr@vpo
this.startIndex = 0; O({-lI
else{ :Y [r^=>
this.startIndex = indexes Yg#)@L
?%HtPm2< %
[startIndex / pageSize];
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} IczEddt@'
} ?D6rFUs9;
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publicint getNextIndex(){ w`Dzk.2
int nextIndex = getStartIndex() + EF{_-FXY
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pageSize; !lF|90=
if(nextIndex >= totalCount) 6X:-Z3
return getStartIndex(); #|8!0]n'
else Sk$XC
return nextIndex; U<NpDjc"
} g5to0
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publicint getPreviousIndex(){ m-a_<xo
int previousIndex = getStartIndex() - .-N9\GlJ,d
;r[=q u\
pageSize; um&e.V)N
if(previousIndex < 0) B%9[
return0; :OBggb#?!
else w|PZSOJ
return previousIndex; xZmKKKd0*
} /BVNJNhz
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} Bd"7F{H
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抽象业务类 ,Ql3RO,
java代码: 1)NX;CN
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/** *(d^k;
* Created on 2005-7-12 ^B?koU l^
*/ j>R7OGg'
package com.javaeye.common.business; -ij1%#t z
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import java.io.Serializable; xMhR;lKY
import java.util.List; Z#;ieI\
e= "/oo
import org.hibernate.Criteria; a+mq=K
import org.hibernate.HibernateException; lLtC9:
import org.hibernate.Session; ^O\tN\g;c
import org.hibernate.criterion.DetachedCriteria; \{+7`4g
import org.hibernate.criterion.Projections; m$hSL4N
import O,JthlAV4
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org.springframework.orm.hibernate3.HibernateCallback; uD:O[H-x
import INzQ0z-z
!1"~tA!+p=
org.springframework.orm.hibernate3.support.HibernateDaoS S_2I8G^A
hY'"^?OP
upport; G';oM;~/|
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import com.javaeye.common.util.PaginationSupport; J(/
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public abstract class AbstractManager extends :@b>,{*4zS
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HibernateDaoSupport { GJy,)EO6{
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privateboolean cacheQueries = false; )_2!1
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privateString queryCacheRegion; cB<0~&
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publicvoid setCacheQueries(boolean 3+ i(fg_
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cacheQueries){ (%+DE4?
this.cacheQueries = cacheQueries; }>frK#S
} \wDOE(>
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publicvoid setQueryCacheRegion(String p-KuCobz]
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queryCacheRegion){ 4?yc/F=kI
this.queryCacheRegion = ;- ]f4O8
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queryCacheRegion; ,CM$A}7[
}
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publicvoid save(finalObject entity){ ir,Zc\C
getHibernateTemplate().save(entity); BTd'bD~EA
} LK:|~UV?
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publicvoid persist(finalObject entity){ q}\\p
getHibernateTemplate().save(entity); GF/p|I D
} \v-> '
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publicvoid update(finalObject entity){ Ha+FH8rZ
getHibernateTemplate().update(entity); !&'xkw `
} b$Uwj<v
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publicvoid delete(finalObject entity){ dNJK[1e6
getHibernateTemplate().delete(entity); <&L;9fr
} =v;-{oN!
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publicObject load(finalClass entity, BgpJ;D+N4
Bgs~1E @8V
finalSerializable id){ 3.dUMJ$_
return getHibernateTemplate().load @JEr/yy
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(entity, id); T:!sfhrZ~<
} ,<vrDHR
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publicObject get(finalClass entity, $Jr`4s
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finalSerializable id){ 'Yd%Tb|*
return getHibernateTemplate().get dIpt&nH&$
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(entity, id); rf`Br\g8
} lMm-K%(2
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publicList findAll(finalClass entity){ }zobIfIF
return getHibernateTemplate().find("from &J~S $
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" + entity.getName()); H|TzD"2N
} Bw#ubQJ8}
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publicList findByNamedQuery(finalString I Mv^ 9T:
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namedQuery){ q;>BltU
return getHibernateTemplate eh`V#%S=
3,F/i+@
().findByNamedQuery(namedQuery); h?ia4t
} Fb``&-Qm:
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publicList findByNamedQuery(finalString query, <7jb4n<
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finalObject parameter){ ~F(+uJbO
return getHibernateTemplate RV$+g.4
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().findByNamedQuery(query, parameter); )Xh_q3=
} 9e1 6 g
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publicList findByNamedQuery(finalString query, ^c\ IZ5
?:?4rIZ<
finalObject[] parameters){ Lmwh`oOl
return getHibernateTemplate ;ULC|7rL
' 4~5ez|:
().findByNamedQuery(query, parameters); H< ;Fb;b
} *!'&:
f^)uK+:.
publicList find(finalString query){ +2zuIW.
return getHibernateTemplate().find O&,O:b:@
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(query); 9 <KtI7
} O$Vm#|$sq
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publicList find(finalString query, finalObject x}.d`=
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parameter){ PEBFN
return getHibernateTemplate().find ?nZ <?
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(query, parameter); @ >(u:.
} z9ShP&^4[
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public PaginationSupport findPageByCriteria B"PHJj
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(final DetachedCriteria detachedCriteria){ 5(|M["KK~
return findPageByCriteria -WUYE
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); }Hz-h4Z
} Q$)|/Y))
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public PaginationSupport findPageByCriteria <}
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(final DetachedCriteria detachedCriteria, finalint ,%h!% nz!
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startIndex){ &ZE\@Vc
return findPageByCriteria ;x-H$OZX
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(detachedCriteria, PaginationSupport.PAGESIZE, v{2DBr
tin|,jA =
startIndex); ;a#*|vx
} *9vA+uN
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public PaginationSupport findPageByCriteria 9*KMbd^T
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(final DetachedCriteria detachedCriteria, finalint U+;>S$
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pageSize, ^QAiySR`0
finalint startIndex){ fhV0S>*<
return(PaginationSupport) z8[H:W#G
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getHibernateTemplate().execute(new HibernateCallback(){ `.'i V[fr
publicObject doInHibernate lV<Tsk'
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(Session session)throws HibernateException { Lq-33#n/
Criteria criteria = |:9Ir^
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detachedCriteria.getExecutableCriteria(session); o}=.
int totalCount = ?Hi}nsw
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((Integer) criteria.setProjection(Projections.rowCount Mjj}E
>&
`x}
Dk<HF
()).uniqueResult()).intValue(); "XNu-_$N<a
criteria.setProjection =#(0)p$EC
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(null); Px?Ao0)Z,
List items = 'qV3O+@MF
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criteria.setFirstResult(startIndex).setMaxResults &|N%#pYS
fYhR#FVI
(pageSize).list(); D#7_TKX
PaginationSupport ps = ,?k%jcR
5#0e={X
new PaginationSupport(items, totalCount, pageSize, ]G0dS
Fh{j
w,Z"W;|
startIndex); gcg>Gjp
return ps; YZGS-+
} w(/DTQc~d
}, true); -@2'I++"@
} A)Qh
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public List findAllByCriteria(final 1TNz&=e
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DetachedCriteria detachedCriteria){ .Z=Ce!
return(List) getHibernateTemplate 8geek$FY x
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().execute(new HibernateCallback(){ st?gA"5w
publicObject doInHibernate 7qg<[
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(Session session)throws HibernateException { CE#\Roi x)
Criteria criteria = *bA+]&dj\
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detachedCriteria.getExecutableCriteria(session); 9g
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return criteria.list(); 3;a
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} Xsd$*F@<
}, true); \+k, :8s/
} ^/>Wr'w
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@
public int getCountByCriteria(final J/'M N
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DetachedCriteria detachedCriteria){ 5"JU?e59M
Integer count = (Integer) F7{R~mS;
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getHibernateTemplate().execute(new HibernateCallback(){ 1")FWN_K/T
publicObject doInHibernate p9-0?(]
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(Session session)throws HibernateException { G#H9g PY
Criteria criteria = bD35JG^&i
RF_[?O)Q
detachedCriteria.getExecutableCriteria(session); W+gpr|R2
return 4xm&pQo{V6
'>3`rsu
criteria.setProjection(Projections.rowCount x;]x_fz
.^i<xY
()).uniqueResult(); XGfzEld2"
} ]gu1#
}, true); 6Rcua<;2P
return count.intValue(); ~TDzq -U)
} 4`nqAX~'f
} :peqr!I+K
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用户在web层构造查询条件detachedCriteria,和可选的 %3M95UZ2
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 2 H[ ; v +
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PaginationSupport的实例ps。 T2wv0sHlt
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ps.getItems()得到已分页好的结果集 ~r<p@k=.#0
ps.getIndexes()得到分页索引的数组 Xo Y7/&&
ps.getTotalCount()得到总结果数 @,k7xm$u
ps.getStartIndex()当前分页索引 c/
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ps.getNextIndex()下一页索引 HsnG4OE
ps.getPreviousIndex()上一页索引 \c{R <Hh
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EX:{EmaT
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 c3] C:t+
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 {"m0)G,G
KmQ^?Ad-C
一下代码重构了。 LeSHRoD
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我把原本我的做法也提供出来供大家讨论吧: y"vX~LR
,/&Z3e
首先,为了实现分页查询,我封装了一个Page类: @`w n<%o$
java代码: OV[`|<C '
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/*Created on 2005-4-14*/ DLi?'K3t
package org.flyware.util.page; XJSa]P^B1
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/** 7^MX l
* @author Joa d+6]u_J
* ;i\C]*
*/ F$Q04Qw
publicclass Page { RN[]Jt#6
<Ct_d
Cc
/** imply if the page has previous page */ (#o t^
privateboolean hasPrePage; !v9lk9SV
)TU<:V
/** imply if the page has next page */ h*Je35
privateboolean hasNextPage; DyfsTx
Mra35
/** the number of every page */ O*G1 QX
privateint everyPage; l~J*' m2
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/** the total page number */ 5ZK&fKeCF
privateint totalPage; / p)F>WR
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/** the number of current page */ s+,&|;Q
privateint currentPage; m'x;,xfY&F
b,@aqu
/** the begin index of the records by the current ~Ky4+\6o>
J8<J8x4
query */ gnLn7?
privateint beginIndex; ?n]FNjd
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/** The default constructor */ aV6#t*\J
public Page(){ KX3KM!*
`8:K[gp
} $`ztiVu3
?6P.b6m}0
/** construct the page by everyPage *(QH{!-$s
* @param everyPage a1c1k}
* */ @dgH50o[
public Page(int everyPage){ WVX`<
this.everyPage = everyPage; Qi9-z'
} v`DI<Lt
sx
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/** The whole constructor */ A:# k
public Page(boolean hasPrePage, boolean hasNextPage, DBs DkkB{
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g"hJ{{<
int everyPage, int totalPage, B4g8
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int currentPage, int beginIndex){ Br5o7(AE
this.hasPrePage = hasPrePage; ,^$|R32
this.hasNextPage = hasNextPage; ,gx)w^WTm
this.everyPage = everyPage; 9}P"^N
this.totalPage = totalPage; Gy"%R-j7
this.currentPage = currentPage; UBZ9A
this.beginIndex = beginIndex; Tu m_aI
} g|%L"-%gJ
p_2pU)%
/** D WiBG
* @return
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* Returns the beginIndex. DN8}glVxV
*/ ~i0R^qfr
publicint getBeginIndex(){ / T
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return beginIndex; |/`%3'4H
} ,EpH4*e
A??@AP[7M
/** }#`:Qb \U
* @param beginIndex /)>S<X
* The beginIndex to set. cYNV\b4-
*/ lr@#^
publicvoid setBeginIndex(int beginIndex){ 8g~EL{'
this.beginIndex = beginIndex; q]% T:A=
} T:iP="?{
_.V?A*
/** Sq2P-y!w
* @return y$W|~ H
* Returns the currentPage. kkCZNQ~I
*/ X~9j$3lUBR
publicint getCurrentPage(){ HU ;#XU1
return currentPage; F<&!b2)ML
} LnsD
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/** DcD{*t?x
* @param currentPage 1Sz A3c
* The currentPage to set. :t("L-GPW
*/ SA"p\}"
publicvoid setCurrentPage(int currentPage){ s
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this.currentPage = currentPage; 'lz"2@4{
} p0:kz l4$
OO) ~HV4\
/** +IFw_3$
* @return /=?x{(B>
* Returns the everyPage.
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*/ H^%lDz
publicint getEveryPage(){ L1{GL #qV
return everyPage; 5z}w}zdg
} 23F/\2MSG
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/** u{<"NR h
* @param everyPage |*5 =_vF
* The everyPage to set. LNYKm~cN
*/ =='Td[
publicvoid setEveryPage(int everyPage){ J:*-gwv9*m
this.everyPage = everyPage; y046:@v(
} "SxLN
8.:
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+_
/** K5>p89mZ
* @return 2}6%qgnT-
* Returns the hasNextPage. l |2D/K5
*/ V9yl4q-bL
publicboolean getHasNextPage(){ s^Nw%KAv
return hasNextPage; \Q?ip&R
} rqPo)AL
d*8 $>GA
/** @$^bMIj@W
* @param hasNextPage DTRJ/@t
* The hasNextPage to set. o G*5f
*/ G3P&{.v
publicvoid setHasNextPage(boolean hasNextPage){ 6fo3:P*O
this.hasNextPage = hasNextPage; K)tQ]P
} /*FH:T<V
uA tV".
/** d[^KL;b?6
* @return z4%uN|V
* Returns the hasPrePage. C$h<Wt=<
*/ HAz By\M{
publicboolean getHasPrePage(){ 2jJmE&)7,
return hasPrePage; s9;#!7ms
} 6 gL=u-2
Rk<@?(l!6x
/** E51dV:l
* @param hasPrePage }_/Hdmmx
* The hasPrePage to set. q%n6K
*/ p@!nYPr.
publicvoid setHasPrePage(boolean hasPrePage){ Z%zj";C
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this.hasPrePage = hasPrePage; AN:sQX`
} $4kH3+WJ
(/d5UIM{&
/** P9Yy9_a|x
* @return Returns the totalPage. }"vW4
* vy2Q g
*/ Y`7~Am/r;&
publicint getTotalPage(){ j`'`)3f
return totalPage; T3UMCqc=
} QZp6YSz.4
: JzI>/
/** ,j;m!V
* @param totalPage )UgX3+@
* The totalPage to set. (s<Dd2&.H
*/ x9/H/'
publicvoid setTotalPage(int totalPage){ iX u]e;6
this.totalPage = totalPage; RpWTpT1
} '|]e<Mt-
Q)m4_+,d
} ?&G`{Ey
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T{wpJ"F5<]
n~"$^Vr
<?-YTY|
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 `g8E1-]l
f0<hE2
个PageUtil,负责对Page对象进行构造: 2]GdD*
java代码: 1_fZm+oW!
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/*Created on 2005-4-14*/ YBYZ=,"d
package org.flyware.util.page; K8n4oz#z
t*z~5_/
import org.apache.commons.logging.Log; 'E/*d2CDM(
import org.apache.commons.logging.LogFactory; 0iULCK
H9h@ sSg
/** IEKU-k7}Z
* @author Joa 4c
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* U~h'*nV&
*/ xq-17HKs
publicclass PageUtil { GRb*EeT
T2}FYVj?!g
privatestaticfinal Log logger = LogFactory.getLog F(4?tX T
t*@2OW`!
(PageUtil.class); rg0ma
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/** Hsih[f
* Use the origin page to create a new page QK0h6CX
* @param page vS\%3A4^+5
* @param totalRecords TG}*5Z`
* @return 0TfS=scT
*/ tz#gClo
publicstatic Page createPage(Page page, int mRB
xe7O/',pa=
totalRecords){ !d<"nx[2`
return createPage(page.getEveryPage(), ,Y3W?
+!QJTn"3
page.getCurrentPage(), totalRecords); ?)bS['^1)
} 6KD `oUx
<%xS{!'}
/** kb[P\cRa
* the basic page utils not including exception iA8U Yd3Q
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handler y=In?QN{6*
* @param everyPage M?= ;JJ:
* @param currentPage da1]mb=4 5
* @param totalRecords GN KF&M
* @return page uB!kM
*/ N`)$[&NG]
publicstatic Page createPage(int everyPage, int b-3*Nl _%
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currentPage, int totalRecords){ qwIa?!8o
everyPage = getEveryPage(everyPage); 4iW'kuK
currentPage = getCurrentPage(currentPage); D:Q
21Ch
int beginIndex = getBeginIndex(everyPage, {Fzs@,|W.
YF+n
b.0.
currentPage); dw.F5?j`b
int totalPage = getTotalPage(everyPage, Wf{O[yL*
V([~r,
totalRecords); P&Pj>!T5
boolean hasNextPage = hasNextPage(currentPage, ?"z]A7<Hj
mxb06u_
totalPage); h" H2z1$
boolean hasPrePage = hasPrePage(currentPage); k}KC/d9.z
"t^URp3
returnnew Page(hasPrePage, hasNextPage, hJzxbr
<
everyPage, totalPage, <hwy*uBrD
currentPage, a0Ik`8^`
Fg Lrb#
beginIndex); _fZZ_0\Q
} WK="J6K5
*^([ ~[
privatestaticint getEveryPage(int everyPage){ ',GS#~
return everyPage == 0 ? 10 : everyPage; 4t)%<4
} %pXAeeSY`;
<C9 XX~
privatestaticint getCurrentPage(int currentPage){ {O|'U'
return currentPage == 0 ? 1 : currentPage;
{EdH$l>94
} 0rGSH*(
' B
privatestaticint getBeginIndex(int everyPage, int ICAH G7 ,
Me6+~"am/
currentPage){ lN9=TxH1(;
return(currentPage - 1) * everyPage; ~+Z{Q25R
} 1heS*Fwn'
"B_K
XL
privatestaticint getTotalPage(int everyPage, int cUDoN`fSl,
V/LQ<Yke
totalRecords){ RT>{*E<I
int totalPage = 0; VXR]"W=
%lg=YGLQB
if(totalRecords % everyPage == 0) ;Ag
3c+
totalPage = totalRecords / everyPage; WD'#5]#Y
else N{-]F|XX
totalPage = totalRecords / everyPage + 1 ; z5W@`=D
<cA/<3k)
return totalPage; J)mhu}
} [!%![E
Fq9Q+RNMZL
privatestaticboolean hasPrePage(int currentPage){ zD3mX<sw
return currentPage == 1 ? false : true; UX]L;kI
} F#|:`$t
,t)x{I;C)
privatestaticboolean hasNextPage(int currentPage, !?^b[
nC%
2>*%q%81
int totalPage){ e[Abp~@M1
return currentPage == totalPage || totalPage == =TqQbadp
yjJ5P`j]
0 ? false : true; /O]t R
} D5~n/.B"
/x{s5P3
Py`N4y~
} P,sjo u^
>AJSqgHQ,
S~]mWxgZ
WW~+?g5
G|\^{5
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。 f<A5?eKw
.Vq)zi1<
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 ]tY
^0a
Dde]I_f}
做法如下: M4xi1M#%
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 0-{tFN
h5yzwj:C?
的信息,和一个结果集List: :UJ a&$)
java代码: b*ef);
':R,53tjl
7mm1P9Z
/*Created on 2005-6-13*/ f-nz{U
package com.adt.bo; .k[o$z\EkF
x1 1U@jd+1
import java.util.List; )*c>|7G
:a:l
j
import org.flyware.util.page.Page; "[:iXRu
k<+0o))
/** S.!UPkW H
* @author Joa :$+-3_oLMQ
*/ L],f3<
publicclass Result { S(:l+JP
t20PP4FWM
private Page page; .UoOO'1K
ZIdA\_c
private List content; fb da
LSQz"Ll
l
/** TY(bPq
* The default constructor BPr^D0P
*/ xJ2*LM-
public Result(){ Ma|qHg
super(); tTU=+*Io
} P9T5L<5
.Yw'oYnS
/** e*j.
* The constructor using fields ZtHm\VTS
* lD{Aa!\
* @param page ?uMQP NYs
* @param content {D g_?._d
*/ &QNWL]
public Result(Page page, List content){ l1]p'Liuu
this.page = page; dJ?XPo"Cm=
this.content = content;
y<C<_2
} cQ:"-!ff
n[YEOkiG
/** ;+1RUv
* @return Returns the content. XhsTT2B
*/ ~8aJ S,u
publicList getContent(){ X0*QV- RN
return content; ps$7bN C
} LK"
bC
fIGFHZy,
/** e|4&b@
* @return Returns the page. *._|- L
*/ LW:o8ES33
public Page getPage(){ [31p&FxM
return page; 4d:{HLX,
} s_.]4bl.8
,#W
/** 5<L_|d)0"
* @param content |y20Hi':
* The content to set. m5G \}8|
*/ 2&Nb
public void setContent(List content){ $BmmNn#
this.content = content; !.1%}4@Q]
} NA,CZ
c#N<"cy>
/** _lW+>xQ
* @param page HG'{J ^t
* The page to set. y0~Ia:y
*/ 5X.e*;
publicvoid setPage(Page page){ `pd&se'p
this.page = page; 09o~9z0
} d*pF> j
} F_uY{bg
3?E8\^N\n
j]0^y}5f+s
-G,^1AL>
[Pe#kzLX
2. 编写业务逻辑接口,并实现它(UserManager, !se0F.K
W0jZOP5_.$
UserManagerImpl) 7kKy\W
java代码: H&b3{yOa
)rLMIk
u9=SpgB#
/*Created on 2005-7-15*/ G#Ou[*O'
package com.adt.service; #GaxZ
LflFe@2
import net.sf.hibernate.HibernateException; j'i0*"x
ZtVAEIZ)
import org.flyware.util.page.Page; y$hp@m'@C
:ug4g6;#H0
import com.adt.bo.Result; fx8EB8A7K7
QCPID:
/** bN^O}[
* @author Joa ENh!N4vbO
*/ @xsCXCRWVV
publicinterface UserManager { ~](fFa{
OPBt$Ki
public Result listUser(Page page)throws UueD(T;p
z=&z_}M8
HibernateException; 0:KE@=
e$c?}3E!z
} (SVWdgb
)x#5Il
H
]<DNo&fw
Pag63njg?
a'\By?V]
java代码: ')S;[= v
iAMtejw
6{d6s#|%
/*Created on 2005-7-15*/ U-wLt(Y<
package com.adt.service.impl; ~{>?*Gd&T
t"j|nz{m
import java.util.List; B@Nt`ky0*
h?\2_s
import net.sf.hibernate.HibernateException; b=a!j=-D
ea=83 Zj
import org.flyware.util.page.Page; Wi n8LOC
import org.flyware.util.page.PageUtil; cD1o"bq
&$`hQgi
import com.adt.bo.Result; {+zJI-XN/
import com.adt.dao.UserDAO; URcR
import com.adt.exception.ObjectNotFoundException; %[<Y9g,:Q
import com.adt.service.UserManager; o-7>eE}+
vtJV"h?e"3
/** N12:{U
* @author Joa bt+,0\Vg5
*/ A{o 'z_zC
publicclass UserManagerImpl implements UserManager { uQLlA&I"
$N$ FtpB
private UserDAO userDAO; 1-I
Swd'u
*5%*|>
/** (\puf+
* @param userDAO The userDAO to set. [-*F"}D,
*/ ~#:e *:ro
publicvoid setUserDAO(UserDAO userDAO){ AV&yoag1
this.userDAO = userDAO; jn9 ShF
} ~c{:DM
cd;NpN
/* (non-Javadoc) h$C@j~
* @see com.adt.service.UserManager#listUser DJhb
u"$a>S_
(org.flyware.util.page.Page) 0BkV/v1Uc
*/ PM$Ee #62R
public Result listUser(Page page)throws 5CJZw3q
p@&R0>6j
HibernateException, ObjectNotFoundException { BX;5wKfA
int totalRecords = userDAO.getUserCount(); 2^exL h
if(totalRecords == 0) &A!KJ.
throw new ObjectNotFoundException Y ?]G}5
F>|9 52
("userNotExist"); "C%!8`K{a*
page = PageUtil.createPage(page, totalRecords); D1,O:+[;.
List users = userDAO.getUserByPage(page); #:3r4J%+~
returnnew Result(page, users); \9)[#Ld
} <2
p}]q d4j
} Wf02$c0#K
}F`beoMAkM
VmQh$&h
@kngI7=E
1TqF6`;+
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 urY`^lX~
PB~_I=
询,接下来编写UserDAO的代码: &yH#s
8^8
3. UserDAO 和 UserDAOImpl: w`yx=i#
java代码: 6X+}>qy
coQ[@vu
){Z
/*Created on 2005-7-15*/ &B-[oqC?
package com.adt.dao; 1JTbCS
9+CFRYC
import java.util.List; s*,cF6
sz09+4h#
import org.flyware.util.page.Page; si/er"&o
qc!xW,I
import net.sf.hibernate.HibernateException; 4sY[az
9rj('F&1
/** &R]pw`mTH
* @author Joa f[/.I,9U^
*/ hd^x}iK"
publicinterface UserDAO extends BaseDAO { G_oX5:J*
$fArk36O#
publicList getUserByName(String name)throws GXb47_b^
`ypL]$cW
HibernateException; Md(JIlh3
M|CrBJv+F
publicint getUserCount()throws HibernateException; 2tr
:xi@
$>vy(Y
publicList getUserByPage(Page page)throws m^$5K's&
qMgfMhQ7DU
HibernateException; ^E@@YV
'_Wt}{h
} #MTj)P,
, p0KLU\-
EnscDtf(
A|vP$zy
_%IqjJO{=r
java代码: rnvQ<671W
KVijs1q
hYvNcOSks
/*Created on 2005-7-15*/ BF|*"#s
package com.adt.dao.impl; 4: sl(r
5gNLO\
import java.util.List; `mErF%b
IhW7^(p\
import org.flyware.util.page.Page; L~MpY{!3
Qyj(L[K J
import net.sf.hibernate.HibernateException; .w'vD/q;
import net.sf.hibernate.Query; R`He^
&tBA^igXK
import com.adt.dao.UserDAO; R<&FhT]
$Xt;A&l2?
/** KSOO?X0j
* @author Joa u( 9X
*/ UD*+"~
public class UserDAOImpl extends BaseDAOHibernateImpl >~&(P_<b
x YT}>#[
implements UserDAO { 3_J>y
+Jw{qQR/*
/* (non-Javadoc) WFh@%j
* @see com.adt.dao.UserDAO#getUserByName aF])"9
6GOg_P
(java.lang.String) ;:_(7|
*/ wW()Zy0)
publicList getUserByName(String name)throws xKW"X
:Y.e[@!1x
HibernateException { ~L){O*Z
String querySentence = "FROM user in class TSXTc'
A9n41,h
com.adt.po.User WHERE user.name=:name"; Ygx,t|?7
Query query = getSession().createQuery h2&y<Eg >
HXP;0B%4
(querySentence); $nFAu}%C
query.setParameter("name", name); 6h@+?{F.
return query.list(); hNVMz`r
} =~",/I?
6H6Law!)
/* (non-Javadoc) ^f0(aYWx
* @see com.adt.dao.UserDAO#getUserCount() 86{ZFtv
*/ ~>w:;M=sV8
publicint getUserCount()throws HibernateException { _FFv#R*4
int count = 0; -$ali[
String querySentence = "SELECT count(*) FROM ! OfO:L7-
paYz[Xq
user in class com.adt.po.User"; ^?sSx!:bZ
Query query = getSession().createQuery V g6S/-
~*kK4]lP
(querySentence); h&$Py
count = ((Integer)query.iterate().next I9,8HtnA
HqRCjD
()).intValue(); IdmD.k0pJ
return count; 0lf"w@/
} /1N)d?Pcl
Xr2 Wa
/* (non-Javadoc) cE2R r
* @see com.adt.dao.UserDAO#getUserByPage DCK_F8
rT<1S?jR
(org.flyware.util.page.Page) `r9^:TMN
*/ CwB] )QV?
publicList getUserByPage(Page page)throws (ic@3:xR
EGEMZCdk2
HibernateException { `=v@i9cTZ
String querySentence = "FROM user in class rxArTpS{.#
X_!$Pk7ma
com.adt.po.User"; _;VYFs
Query query = getSession().createQuery .Map
|QMT
A5
(querySentence); Y}ky/?q
query.setFirstResult(page.getBeginIndex()) @QX4 \
.setMaxResults(page.getEveryPage()); 5 Af?Yxv
return query.list(); acy"ct*I
} 4zwif&
5Ny0b|+p
} !&6-(q9
WSSaZ9
=
T5V$wmB\W
Ul9b.`6
=3pD:L
至此,一个完整的分页程序完成。前台的只需要调用 Lm.Ik}Gli
fW[_+r]
userManager.listUser(page)即可得到一个Page对象和结果集对象 ~"\P~cg0J
.;j"+Ef
的综合体,而传入的参数page对象则可以由前台传入,如果用 y
"<JE<X
}Uq/kei^P
webwork,甚至可以直接在配置文件中指定。 ![j(o!6&
;wpW2%&
下面给出一个webwork调用示例: R<t&F\>
java代码: 8db6(Q~P
*eMLbU7
`}ZL'\G
/*Created on 2005-6-17*/ )y5iH){!
package com.adt.action.user; FmR\`yY_,
lej^gxj/2
import java.util.List; Wl?<c
uw00
`dP? 2-Z
import org.apache.commons.logging.Log; -IGMl_s
import org.apache.commons.logging.LogFactory; NCp%sGBmG
import org.flyware.util.page.Page; x9TuweG
cFe V?a
import com.adt.bo.Result; ;,R[]B01u
import com.adt.service.UserService; E=3#TBd
import com.opensymphony.xwork.Action; :E}6S
&(GopWR`e
/** 8 `yB
* @author Joa v)TUg0U=,
*/
$.=5e3
publicclass ListUser implementsAction{ &C\=!r0j^
+~@7"
|d
privatestaticfinal Log logger = LogFactory.getLog tYF$#Nor#k
K T%i,T
(ListUser.class); x!Y( Y=i>
IwOfZuS
private UserService userService; tP -5
% 1OC#&
private Page page; E`U&Z
tvv[$b&
privateList users; ]Pz|Oi+]
uT#Acg
/* oXvdR(Sb^
* (non-Javadoc) #vnefIcBf
* <d3PDO@w/
* @see com.opensymphony.xwork.Action#execute() 4,o
%e,z
*/ `e4o 1*
publicString execute()throwsException{ ZE{aS4c
Result result = userService.listUser(page); dVij <! Lu
page = result.getPage(); N;e}dwh&
users = result.getContent(); /vMQF+
return SUCCESS; jo]m12ps
} )j$b9ZBk
p|xs|O6{
/** D:+)uX}MOf
* @return Returns the page. >B @i
E
*/ tj`tLYOZ@-
public Page getPage(){ AEi WL.*.
return page; HCI'q\\
} yIn/Y 0No
7uWJ6Wk
/** \H},ouU
* @return Returns the users. W*1d
X"S
*/ #i'C
publicList getUsers(){ T2;v<(
return users; .~FKyP>[$
} #JHy[!4
3U :YA&K(
/** cg>!<T*
* @param page k8!hvJ)?
* The page to set. UUt~W
*/ ay!6T`U`
publicvoid setPage(Page page){ <L[T'ZE+
this.page = page; yBUZVqqDa
} r@N39O*Wq
LG"BfYy6
/** L{+&z7M
* @param users &ryl$!!3H
* The users to set. .aVHd<M
*/ 6{Krw\0
publicvoid setUsers(List users){ Tw`F?i~
this.users = users; H8(0.IR
} we6+2
(CKhY~,/u
/** ,(1vEE[9-
* @param userService (,d4"C
* The userService to set. @]?? +f}#
*/ :mCw.Jz<h
publicvoid setUserService(UserService userService){ LZ=wz.'u
this.userService = userService; <(u3+`f1s
} G_4K+
-K
} }z9I`6[
a>;3
j
+xoyKP!
A52LH,
c+)36/; X
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, kMfc"JXF
dXf]G6
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 OX#eLco
o(v"?Y 6
么只需要: &etL&s v
java代码: =!I8vQ>
u&?yPR
b<29wL1
<?xml version="1.0"?> llTQ\7zP
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork /6i Tq^.%
Mm:a+T
1.0//EN" "http://www.opensymphony.com/xwork/xwork- Zpn*XG
Y&1!Z*OL;
1.0.dtd"> @'k,\$ /
rw40<SS"Z
<xwork> v%69]a-T
e{qp!N1!
<package name="user" extends="webwork- .P|+oYT&g
7$Z)fkx.
interceptors"> T2/v}
46Y7HTwE
<!-- The default interceptor stack name 0{U ]STj
{y+v-v/#
--> )zk?yY6
<default-interceptor-ref 2yi*eR
B J:E,P`_
name="myDefaultWebStack"/> dd?x5|/#
#Of<1
<action name="listUser" #2ZrdD"5kQ
;:8jxkx6%
class="com.adt.action.user.ListUser"> e$p1Th*|]4
<param
Xv?
S
$w";*">:0
name="page.everyPage">10</param> 1%]{0P0?[
<result kp#c:ym
W[jW;uk
name="success">/user/user_list.jsp</result> f//j{P[
</action> n{qa ]3
"R\\\I7u
</package> ^Yf)lV&[
dctA`W@:-
</xwork> ~,M;+T}[r
Kc-A-P &Ry
o%N0K
I49=ozPP
n41\y:CAo
{$u@6&
B
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 gs`27Gih
FzsS~C$wH{
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。 K_<lO,[S
7DHT)9lD/
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 qI4R`P"
}{w_>!ee
+i q+
$J;=Ux)$
W:;`
我写的一个用于分页的类,用了泛型了,hoho 2\iD;Z#gM
9^C!,A{u4
java代码: ^c[CyZ:a
=w;xaxjL
Rm[rQ}:
package com.intokr.util; i+T0}M<
q9a
wzj
import java.util.List; ~;O=
7
J~yd]L>
/** *fuGVA
* 用于分页的类<br> zM9) .D
H
* 可以用于传递查询的结果也可以用于传送查询的参数<br> =%nqMV(y
* CB{k;H
* @version 0.01 :'^dy%&UB
* @author cheng -c<1H)W
*/ rTH[?mkf4
public class Paginator<E> { ?XTg%U
privateint count = 0; // 总记录数 |]2eGrGj4
privateint p = 1; // 页编号 3Oig/KZ
privateint num = 20; // 每页的记录数 2}xFv2X
privateList<E> results = null; // 结果 |Z^c#R
)lngef
/D_
/** 1+PNy d
* 结果总数 gp|7{}Q{
*/ 'k(~XA}X:
publicint getCount(){ Q+%m+ /Zq
return count; aBA#\eV
} GO:1
Z?^
J?,!1V=
publicvoid setCount(int count){ ,[K)E
this.count = count; n9-q5X^e>
} 2YP"nj#
@ T~#Gwv
/** WY.\<$7
* 本结果所在的页码,从1开始 l.NkS
* |2t7mat
* @return Returns the pageNo. qeO6}A"^|
*/ $0`$)(Y
publicint getP(){ k~s>8N:&G
return p; <K.C?M(9
} ZZ.0'
JXR/K=<^
/** L!}j3(I
* if(p<=0) p=1 ?\p%Mx?
* /o06h y
* @param p !A^w6Q;`V
*/ 2O)Kn
q
publicvoid setP(int p){ wGQ hr="
if(p <= 0) %H 6ZfEO
p = 1; RT+30Q?
this.p = p; hK9oe%kU~
} >J75T1PH=
yOCcp+`T}
/** 4`5Qt=}
* 每页记录数量 E,yzy[gl
*/ =x.v*W]F`
publicint getNum(){ ([XyW{=h!
return num; "62Ysapq+
} Go+,jT-
!&:W1Jkp(
/** OXCml(>{
* if(num<1) num=1 ^[?+=1
k
*/ 2.L6]^N p(
publicvoid setNum(int num){ dgqJ=+z 0y
if(num < 1) ^9V8 M9
num = 1; e!x-:F#4j
this.num = num; h'q0eqYeu)
} _R<V8g1f
uc (yos
/** RO3e
* 获得总页数 )+{omQ7v
*/ ujp,D#xHP
publicint getPageNum(){ L!Zxc~
return(count - 1) / num + 1; NVh>Q>B$_
} 2,QApW_Y
kE(-vE9
/** 6Oqnb+
* 获得本页的开始编号,为 (p-1)*num+1 D30Z9_^%:
*/ mM^8YL
publicint getStart(){ LVcy.kU@]
return(p - 1) * num + 1; ppo$&W
&z
} H=SMDj)s+
mt6uW+t/
/** wTuRo
J
* @return Returns the results. bFdg'_
*/ J<:D~@qq
publicList<E> getResults(){ hE`%1j2(
return results; 3'@jRK
} >U
Ich
g:6}zHK
public void setResults(List<E> results){ ]X;*\-
this.results = results; *z:lq2"G
} LFM5W&?
(IQ L`3f%
public String toString(){ XK9*,WA9r
StringBuilder buff = new StringBuilder VqT[ca\
52R.L9Ai
(); RuEnr7gi
buff.append("{"); *wZV*)}
buff.append("count:").append(count); -EIMh^
buff.append(",p:").append(p); hnLgsz
buff.append(",nump:").append(num); 7}7C0mV3
buff.append(",results:").append BCDf9]X
]qG5Ne_
(results); vh3iu+
buff.append("}"); <yaw9k+P
return buff.toString(); IG@&l0ARL
} 0_Z|y/I.
iP\&fZY_
} I8wVvs;k
E6\~/=X=%
^9~%=k=