Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 >o#wP
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 gCr|e}w-
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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 f\U&M,L\'
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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 ZCFf@2&z8
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。 xcvr D
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分页支持类: wKS-O%?
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java代码: %`1CE\f
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package com.javaeye.common.util; ##FNq#F
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import java.util.List; Ca@=s
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publicclass PaginationSupport { 0&IXzEOr
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publicfinalstaticint PAGESIZE = 30; L"!ZY
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privateint pageSize = PAGESIZE; JOx,19r
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privateList items;
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privateint totalCount; &_/%2qs
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privateint[] indexes = newint[0]; 6eYf2sZ;J
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privateint startIndex = 0;
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public PaginationSupport(List items, int s7nX\:Bw:
9me}&Fdr
totalCount){ 1~5q:X
setPageSize(PAGESIZE); H4'DL'83
setTotalCount(totalCount); ''OInfd?
setItems(items); wYO"znd
setStartIndex(0); b}Hl$V(uD
} 1m<?Q&|m$
!H|82:`t+
public PaginationSupport(List items, int Ryba[Fz4Di
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gul&
totalCount, int startIndex){ h>Uid
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setPageSize(PAGESIZE); vo6[2.HS
setTotalCount(totalCount); .d~]e2x
setItems(items); V l~Y
setStartIndex(startIndex); C7 ]DJn
} d9-mWz(V+
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public PaginationSupport(List items, int l P$r
8\)U|/A7
totalCount, int pageSize, int startIndex){ iQ|,&K0d]
setPageSize(pageSize); Zp(=[n5
setTotalCount(totalCount); yI.}3y{^5
setItems(items); nJ*mEB
setStartIndex(startIndex); '`]n_$f'
} H/Ec^Lc+_
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publicList getItems(){ |v$%V#Bo
return items; \YlF>{LVe
} -M:hlwha
q]N?@l]
publicvoid setItems(List items){ }>;ht5/i/
this.items = items; wHOlj)CZ
} o\]:!#r{T
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publicint getPageSize(){ juCG?}di;
return pageSize; XnE
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} 9jMC|oE
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publicvoid setPageSize(int pageSize){ i'Y'HI
this.pageSize = pageSize; cNuHXaWp
} k~1j/VHv
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publicint getTotalCount(){ j(%gMVu
return totalCount; 'z-;* !A}j
} L`jB)wF/J
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publicvoid setTotalCount(int totalCount){ Cgz&@@j,]
if(totalCount > 0){ nrTv=*tDj
this.totalCount = totalCount; 9P7xoXJ@y
int count = totalCount / T,WKoB
bvipbf[m<
pageSize; nxyjL)!)0
if(totalCount % pageSize > 0) %wt2F-u
count++; [arTx^
indexes = newint[count]; <o&o=Y8
for(int i = 0; i < count; i++){ DIG0:)4R.
indexes = pageSize * 9U|<q
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i; msc 1^2
} OB?S kR
}else{ kRN|TDx(
this.totalCount = 0; :F7k{~
} NV}RRs
} =de<WoKnu2
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publicint[] getIndexes(){ b|sc'eP#?
return indexes; @PPR$4
} a{]g+tGH
l_c^ .D
publicvoid setIndexes(int[] indexes){ *?_qE
this.indexes = indexes; `E} p77
} <$jKy 3@
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publicint getStartIndex(){ Pgn_9Y?<
return startIndex; x?, ~TC4
} G&x'=dJ
p-5Pas
publicvoid setStartIndex(int startIndex){ 9W1;Kb|Z<
if(totalCount <= 0) G;(onJz
this.startIndex = 0; y$IaXr5L
elseif(startIndex >= totalCount) (O8,zqP9l
this.startIndex = indexes L!;^#g
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[indexes.length - 1]; |H ^w>mk
elseif(startIndex < 0) !}>eo2$r^
this.startIndex = 0; F2IC$:e
M
else{ '8)Wd"[
this.startIndex = indexes l60ikc4$I
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[startIndex / pageSize]; >vlQ|/C
} r0F_;
} RVc)")
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publicint getNextIndex(){ }FPM-M3y
int nextIndex = getStartIndex() + {UB%(E[Mr
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pageSize; paW'R +Rck
if(nextIndex >= totalCount) N0=-7wMk(Z
return getStartIndex(); CE~r4
else f%2%T'Q
return nextIndex; hzaLx8L
} :3*`IB !
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publicint getPreviousIndex(){ C/F@ ]_y
int previousIndex = getStartIndex() - W`#gpi)7N
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pageSize; mR" uhm}q
if(previousIndex < 0) {bN Y
return0; 6 -]>]Hr-
else za,6du6
return previousIndex; fC_zX}3
} #hIEEkCp +
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} k_]\(myq
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抽象业务类 YMi/uy
java代码: T3=(`
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/** S#,+Z7
* Created on 2005-7-12 s4(Wp3>3i
*/ $h,d?
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package com.javaeye.common.business; ZQ|5W6c
<BSSa`N`
import java.io.Serializable; w{3ycR
import java.util.List; u[)_^kIE(n
W:WQaF`2x
import org.hibernate.Criteria; cI5N"U@yN
import org.hibernate.HibernateException; zei6S
import org.hibernate.Session; pg+b[7
import org.hibernate.criterion.DetachedCriteria; '?5S"??
import org.hibernate.criterion.Projections; +6
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import yKYl@&H/%
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org.springframework.orm.hibernate3.HibernateCallback; bV_j`:MD
import Z%#^xCz;w>
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org.springframework.orm.hibernate3.support.HibernateDaoS {t&*>ma6)
d [r-k 2
upport; J<rlz5':
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import com.javaeye.common.util.PaginationSupport;
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public abstract class AbstractManager extends x.ba|:5
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HibernateDaoSupport { -OWZ6#v(
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privateboolean cacheQueries = false; \Dfm(R
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privateString queryCacheRegion; +s ULo
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publicvoid setCacheQueries(boolean ^+wk
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cacheQueries){ Apmw6cc
this.cacheQueries = cacheQueries; K U$`!h
} /HZv
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publicvoid setQueryCacheRegion(String T<P0T<
]w!0u2K<Q\
queryCacheRegion){ wqP2Gw7jh6
this.queryCacheRegion = >VP5vkv=
b:1 L@8s;
queryCacheRegion; /[%w*v*'
} okstY4f'
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publicvoid save(finalObject entity){ D^|9/qm$
getHibernateTemplate().save(entity); K3L"^a
} .%IslLZ
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publicvoid persist(finalObject entity){ W!91tzs:
getHibernateTemplate().save(entity); /D'M 24
} ?_%u)S*g
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publicvoid update(finalObject entity){ xz8G}Ku
getHibernateTemplate().update(entity); FIS "Z(
} l[oe*aYN7
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publicvoid delete(finalObject entity){ s9i|mVtm8
getHibernateTemplate().delete(entity); q*bt4,D&Es
} tb,9a!?
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publicObject load(finalClass entity, t+O e)Ns
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finalSerializable id){ q_sEw~~@!
return getHibernateTemplate().load %m`zWg-
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(entity, id); 'OD)v
} h)cY])tGtK
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publicObject get(finalClass entity, 0q#"clw
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finalSerializable id){
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return getHibernateTemplate().get [9AM\n>g
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(entity, id); <( EyXV
} wt?o
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publicList findAll(finalClass entity){ Q+'nw9:;T
return getHibernateTemplate().find("from UV@0gdy[
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" + entity.getName()); Bd#
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} |55dbL$w
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publicList findByNamedQuery(finalString 64umul
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namedQuery){ Q|c|2byb
return getHibernateTemplate i%F<AY\O)
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().findByNamedQuery(namedQuery); nQ-mmY>#
} R,,Qt
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publicList findByNamedQuery(finalString query, :h*a
rT4{
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finalObject parameter){ 3{ "O,h
return getHibernateTemplate .3X Y&6
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().findByNamedQuery(query, parameter); +qy6d7^
} U\vY/6;JI
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publicList findByNamedQuery(finalString query, cG_Vc[
q.W>4 k
finalObject[] parameters){ G3a7`CD
return getHibernateTemplate Ej"u1F14J
jatr/
().findByNamedQuery(query, parameters); 5k$vlC#[H
} WU)Ss`s \
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publicList find(finalString query){ HID([Wk
return getHibernateTemplate().find NBOCt)C;H
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(query); zK;XFN#U^
} e;(
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publicList find(finalString query, finalObject E!mmLVa9
qZ+H5AG2
parameter){ v&;:^jJ8
return getHibernateTemplate().find D*2\{W/
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(query, parameter); ;;#`#v
} _A'{la~k
{/ 2E*|W~I
public PaginationSupport findPageByCriteria ?9xu{B>6
y{=>$C[
(final DetachedCriteria detachedCriteria){ ZA820A>2!
return findPageByCriteria |5MbAqjzC
`^6 ,kI-c
(detachedCriteria, PaginationSupport.PAGESIZE, 0); ~ap2m
} 6q/?-Qcy
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public PaginationSupport findPageByCriteria ."6[:MF
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(final DetachedCriteria detachedCriteria, finalint d%ME@6K)
Hj6'pJ4
startIndex){ ue{xnjw>U
return findPageByCriteria ,={t8lN
{' 5qv@3
(detachedCriteria, PaginationSupport.PAGESIZE, m;,xmEp
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startIndex); ^3~e/P KM
} ^?GmrHC)
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public PaginationSupport findPageByCriteria 1[PMDS_X
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(final DetachedCriteria detachedCriteria, finalint $B
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pageSize, /'wF2UR
finalint startIndex){ :dnJY%/q
return(PaginationSupport) bF-"tm
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getHibernateTemplate().execute(new HibernateCallback(){ E6A/SVp
publicObject doInHibernate ;['a
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(Session session)throws HibernateException { ,o#kRWRG
Criteria criteria = HdX2YPYn;
8%:]W^
detachedCriteria.getExecutableCriteria(session); ))T>jh
int totalCount = WAPhv-6
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((Integer) criteria.setProjection(Projections.rowCount p]T"|! d
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()).uniqueResult()).intValue(); {?8B,G2r
criteria.setProjection 7E7dSq
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(null); *?%
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List items = egR-w[{
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criteria.setFirstResult(startIndex).setMaxResults tWPO]3hW
{D`T0qPT[
(pageSize).list(); osP\DiQ
PaginationSupport ps = $l[Rh1z`;+
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new PaginationSupport(items, totalCount, pageSize, 01@t~v3!Z
7hw .B'7
startIndex); 04@cLDX8uB
return ps; RHY4P4B<v>
} 9
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}, true); AMCyj`Ur
} L>9R4:g
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public List findAllByCriteria(final ;;U:Jtn2
9Kv|>#zff
DetachedCriteria detachedCriteria){ b[ w;i]2
return(List) getHibernateTemplate !CY&{LEYn0
[iS$JG-
().execute(new HibernateCallback(){ }JgYCsF/f
publicObject doInHibernate 8|g<X1H{M
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(Session session)throws HibernateException { dK9Zg,DZL
Criteria criteria = kLP0{A
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detachedCriteria.getExecutableCriteria(session); =H`Q~Xx
return criteria.list(); i@P}{
} jLVl4h&
}, true); W;_E 4
} kU l
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public int getCountByCriteria(final WcUJhi^\C
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DetachedCriteria detachedCriteria){ \Y|*Nee}XP
Integer count = (Integer) YTaLjITG
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getHibernateTemplate().execute(new HibernateCallback(){ 8Cx^0
publicObject doInHibernate 1Y j~fb(
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(Session session)throws HibernateException { "&+3#D
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Criteria criteria = 5FeFN)
@'2m$a
detachedCriteria.getExecutableCriteria(session); +0$/y]k
return r%]Qlt~K
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criteria.setProjection(Projections.rowCount X` YwP/D
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()).uniqueResult(); 6<'K~1do:
} &2.u%[gO[q
}, true); (R}ii}&
return count.intValue(); 5TKJWO.
} OjE`1h\
} wIvo"|%
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`)$_YZq|SR
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用户在web层构造查询条件detachedCriteria,和可选的 7Ke&0eAw
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ){;02^tX
kL*0M<0 (
PaginationSupport的实例ps。 qdD)e$XW,
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ps.getItems()得到已分页好的结果集 ed!>)Cb
ps.getIndexes()得到分页索引的数组 V
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ps.getTotalCount()得到总结果数 pW\'ZRj
ps.getStartIndex()当前分页索引 {p<Zbm.
ps.getNextIndex()下一页索引 ()T[$.(
ps.getPreviousIndex()上一页索引 G=9d&N
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Rd*[%)
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 vG41C k1
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一下代码重构了。 ?9+@+q
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我把原本我的做法也提供出来供大家讨论吧: >h~IfZU1
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首先,为了实现分页查询,我封装了一个Page类: PXKJ^fa
java代码: <cN~jv-w$
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/*Created on 2005-4-14*/ CB\{!
package org.flyware.util.page; z`@^5_
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/** iP@6hG`:
* @author Joa iPG0o
%
* {}~: &.D
*/ YvL?j
publicclass Page { Dh|w^Q
C@\{ehG
/** imply if the page has previous page */ V<Z'(UI
privateboolean hasPrePage;
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/** imply if the page has next page */ -NGK@Yk22
privateboolean hasNextPage; N3BL3:@O
8,T4lb<<
/** the number of every page */ IIFMYl gF
privateint everyPage; UPU+ver
2!1.E5.I
/** the total page number */ Rfb?f}j
privateint totalPage; hS [SRa'.
#Il_J\#
/** the number of current page */ PG%0yv%
privateint currentPage; Xf'=+f2p
`(y(w-:W1
/** the begin index of the records by the current w&h2y4
6rti '
query */ Pn.bVV:
privateint beginIndex; TA18 gq
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/** The default constructor */ @LE[ac
public Page(){ f7urJ'!V
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} bp<^R
l(W[_ D
/** construct the page by everyPage 4Aes#{R3v
* @param everyPage ,Dmc2D
* */ ]:]H:U]p
public Page(int everyPage){ +]xFoH
this.everyPage = everyPage; Pf_F59"
} B0}~G(t(
-XK0KYhgW
/** The whole constructor */ F4#g?R::U
public Page(boolean hasPrePage, boolean hasNextPage, rt7<Q47QE
Z [Xa%~5>5
`NRH9l>B7
int everyPage, int totalPage, `m@U!X
int currentPage, int beginIndex){ : 9!%ZD
this.hasPrePage = hasPrePage; "bQ[CD
this.hasNextPage = hasNextPage; j F"YTr6
this.everyPage = everyPage; | $^;wP
this.totalPage = totalPage; U
5w:"x
this.currentPage = currentPage; z$lF)r:Bc
this.beginIndex = beginIndex; CBT>"sYE1
} c{#yx_)V&
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/** *O$CaAr\s
* @return f|EUqu%E
* Returns the beginIndex. 7v}x?I
*/ 2RtHg_d_l
publicint getBeginIndex(){ '!h/B;*(
return beginIndex; 4Cb9%Q0
}
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&a)eJF]:!
/** q0mOG^
* @param beginIndex l;X|=eu'
* The beginIndex to set. ?9MVM~$
*/ 4DWwbO
publicvoid setBeginIndex(int beginIndex){ [dX`K`k
this.beginIndex = beginIndex; z2c5m
} M(q'%XL^
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/** DC+wD
Bp;
* @return SS|z*h
Z
* Returns the currentPage. ;oOv/3
*/ }u{gR:lZ
publicint getCurrentPage(){ gYAF'?
return currentPage; we7c`1E
} .aOnGp
{i~8 :
/** )vB2!H/
* @param currentPage y %8op:'
* The currentPage to set. H5>hx{
*/ /
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publicvoid setCurrentPage(int currentPage){ :6kj EI
this.currentPage = currentPage; Oc?+M 5
} &p
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q6P
wZ_
/** hIv@i\`
* @return (n{wg(R
* Returns the everyPage. pI[ZBoR~
*/ \kamcA
publicint getEveryPage(){ )U<Y0bZA!
return everyPage; T5Eseesp
} i7[uLdQ
NVV}6TUV
/** (WlIwKP
* @param everyPage K!AAGj`
* The everyPage to set. W1aa:hEf
*/ qf)$$ qi
publicvoid setEveryPage(int everyPage){ H&}ipaDO
this.everyPage = everyPage; ^t"iX9
} "I-
w
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/** ,"}Rg1\4t
* @return >cmE
t
* Returns the hasNextPage. 9?T{}| ?
*/ ^D67y%
publicboolean getHasNextPage(){ ?wpB`
return hasNextPage; M.}7pJ7f
} uZKP"Oy
$WQq?1.9
/** TB6m0qX(
* @param hasNextPage >"3>s%
* The hasNextPage to set. #Sg\q8(O
*/ HHk)ZfWRo
publicvoid setHasNextPage(boolean hasNextPage){
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this.hasNextPage = hasNextPage; `:{B(+6
} p^m5`{1]x
0Sl]!PZR1
/** 72T I
* @return eHg3}b2r
* Returns the hasPrePage. "](6lB1Oe
*/ 7XrfuG*L$
publicboolean getHasPrePage(){ cvsz%:Vs
return hasPrePage; z+2V4s =
} wgeNs9L
pj|pcv^
/** Y OyX[&oi
* @param hasPrePage }]P4-KqI
* The hasPrePage to set. q!'rz
*/ Z@D*1\TG=
publicvoid setHasPrePage(boolean hasPrePage){ X+8B!F
this.hasPrePage = hasPrePage; |tMn={
} Fr?z"
e59dVFug.U
/** P3tx|:gV
* @return Returns the totalPage. G1T^a>tj4
* Q'apG)0I
*/ !v#xb3"/
publicint getTotalPage(){ fg%&N2/(.B
return totalPage; Y o0FUj
} .~lKBkS`!
jLg@FDb~
/** -#`c5y}P
* @param totalPage "7%:sty
* The totalPage to set. omZO+=8Q
*/ -PB[-CX
publicvoid setTotalPage(int totalPage){ [^H"FA[
this.totalPage = totalPage; w&&2H8
} '$|UwT`s
T0HuqJty
} W\*-xf|"d
sE(HZR1
8Ad606
%6j)=IOts
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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 `A%^UCd
9e!NOl\_;.
个PageUtil,负责对Page对象进行构造: f}%D"gz
java代码: Rxpn~QQ
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.o{0+fC#
/*Created on 2005-4-14*/ 1tzV8(7
package org.flyware.util.page; u }hF8eD
yQS+P8x&|]
import org.apache.commons.logging.Log; <M?:
import org.apache.commons.logging.LogFactory; EER`?Sa(
S|AM9*k9
/** "pxzntY|
* @author Joa &Y P#M|
* USJ-e
*/ DbX{#4lx
publicclass PageUtil { {aKqXL[UP
F#|O@.tDG
privatestaticfinal Log logger = LogFactory.getLog P'@<:S|
84zTCX
(PageUtil.class); %bXx!x8(
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/** zkM"cb13q/
* Use the origin page to create a new page .uo.N
* @param page C=Fzu&N}
* @param totalRecords |C \}P
* @return 4fV3Ear=j
*/ $
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publicstatic Page createPage(Page page, int }Y(]6$uS
$V>98M>j
totalRecords){ !H][LXB~H
return createPage(page.getEveryPage(), ^^` Jcd/
ewNz%_2
page.getCurrentPage(), totalRecords); l|`9:H
} ',7??Q7j&v
=]R3& ]#n
/** wbyE;W
* the basic page utils not including exception '&O/g<Z}q
2],_^XBvB
handler p4> $z& _
* @param everyPage #h!*dj"
* @param currentPage \/7i-B]G7
* @param totalRecords oz'\q0
* @return page !M<{E*
*/ iL{M+Ic
publicstatic Page createPage(int everyPage, int o;"OSp
*=" 8?Z
currentPage, int totalRecords){ jdeV|H} u
everyPage = getEveryPage(everyPage); }G46g#_6d>
currentPage = getCurrentPage(currentPage); [36,eK
int beginIndex = getBeginIndex(everyPage, u]^N&2UW
[mxTa\
currentPage); /76 1o\Q
int totalPage = getTotalPage(everyPage, D-imL;|
m%+IPZ2m
totalRecords); %m5Q"4O
boolean hasNextPage = hasNextPage(currentPage, {MAQ/5
;32#t[ib
totalPage); nq}Q
boolean hasPrePage = hasPrePage(currentPage); `7aDEzmJ
y]..=z_ql
returnnew Page(hasPrePage, hasNextPage, >C WKH~
everyPage, totalPage, 5(2|tJw-H;
currentPage, "bg'@:4F
g3@Rl2yQJ
beginIndex); !
ueN|8'
} I[MgIr^
h 6G/O`:
privatestaticint getEveryPage(int everyPage){ >>[/UFC)n
return everyPage == 0 ? 10 : everyPage; ln*icaDqf
} ~sQjl]
?zJpD8e
privatestaticint getCurrentPage(int currentPage){ /5AW?2)
return currentPage == 0 ? 1 : currentPage; #0I{.Wy]
} |4)
>4m'tZ8
privatestaticint getBeginIndex(int everyPage, int -37a.
a^qNJ?R!
currentPage){ Y-piL8Xc
return(currentPage - 1) * everyPage; Ou>u%
} q+SD6qM
7x]4`#u
privatestaticint getTotalPage(int everyPage, int Sydh2d
,7Y-k'7Kop
totalRecords){ a~h:qpgc
int totalPage = 0; bo"%0?3n
5\mTr)\R
if(totalRecords % everyPage == 0) 1:C:?ZC#c
totalPage = totalRecords / everyPage; n6WY&1ZE~
else :WGtR\tK
totalPage = totalRecords / everyPage + 1 ; 6SJ"Tni8
pi( -A
return totalPage; D8{D[fJ;
} zxb/
i[C~5}%
privatestaticboolean hasPrePage(int currentPage){ @ufo$?D
return currentPage == 1 ? false : true; [@<sFP;g
} >$67 7
>t,M
privatestaticboolean hasNextPage(int currentPage, %1
KbS
[
vq*Q.0 M+
int totalPage){ VO3pm6r5
return currentPage == totalPage || totalPage == 5F+APz7
K`}{0@ilCw
0 ? false : true; QR?yG+VU
} )CPM7>
JG`Q;K
<E;pgw!
} seFGJfN\?f
=-cwXo{Q.O
72W,FU~OD
I7+9~5p
~8 H_u
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。 +1JH
p1pQU={<
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 u*S=[dq
qIUfPA=/_
做法如下: %A1@&xrbl
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 rj]F87"
PupM/?57
的信息,和一个结果集List: !"Yj|Nu6
java代码: s1Ok|31|
s>_V
'z@ 0
/*Created on 2005-6-13*/ Kr'f- {
package com.adt.bo; c'6g*%2k
'XQ`g CF=
import java.util.List; 0Q,g7K<d
}uHrto3M
import org.flyware.util.page.Page; iF5'ygR-Z
c:S] R"
/** W+wA_s2&D
* @author Joa qL6c`(0
*/ "@@I!RwA
publicclass Result { [97:4.
+[@z(N-h
private Page page; j| Wv7
\?>Hu
v
private List content; @53k8
'X).y1'
/** 0<"k8
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* The default constructor <tpmUA[]
*/ 'crlA~/
public Result(){ zepop19
super(); 5IOFSy`
} _$NIp `d
+;BAV
/** 7*Qk`*Ii
* The constructor using fields >4Y3]6N0.F
*
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* @param page eg<bi@C1|
* @param content *D4hq=
*/ ;Mm7n12z C
public Result(Page page, List content){ bawJ$_O_
this.page = page; k$5 s{q
this.content = content; f:*vr['d
} 2 &/v]
1"8yLvtn
/** :(dHY
* @return Returns the content. a8u9aEB
*/ J]W5[)L
publicList getContent(){ <9ig?{'
return content; o)6p A^+
} h1 WT
sAo&
uZ
/** W)'*m-I
* @return Returns the page. MUOa@O,
*/ bQe^Px5
!.
public Page getPage(){ 4p;aS$Q
return page; 4v
p
} ~/NKw:
g&dPd7
/** IcP)FB4
* @param content 4=uhh
* The content to set. 64Lx-avf
*/ R [H+qr
public void setContent(List content){ Yw _+`,W
this.content = content; 0![
+Q4"
} a{!QOX%K
8u[-'pV!
/** i'stw6*J
* @param page ,F&g5'
* The page to set. tg^sCxz9]
*/ RMO,ZVq
publicvoid setPage(Page page){ ]# t6Jwk
this.page = page; gVeEdo`$<
} xI,2LGO
} Sxjub&=
l4T7'U>`
FZreP.2)!
vVGDDDz/
_%'},Xd.z
2. 编写业务逻辑接口,并实现它(UserManager, gTRF^knrY
'
|-JWH
UserManagerImpl) e \O/H<
java代码: '=][J_
~['Kgh_;
/iG*)6*^k
/*Created on 2005-7-15*/ Pxn,Qw*
package com.adt.service; P"sA
p=/m
import net.sf.hibernate.HibernateException; XdH\OJ
TAjh"JJIV
import org.flyware.util.page.Page; ;lYHQQd!,
P`r55@af4
import com.adt.bo.Result; d[rv1s>i
a >\vUv*
/** Ym;*Y !~[
* @author Joa cqxVAzb
*/ 8Sz})UZ
publicinterface UserManager { Spt?>sm
Y8flrM2CwG
public Result listUser(Page page)throws J>d.dq>r
O-)-YVU
HibernateException; "
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0!v->Dk
} 1;<R#>&,*
x@8a''
KZ~*Nz+H2
R$zH]
6q
2_WX
java代码: `6+"Z=:
#c^^=Z
+iOKb c'
/*Created on 2005-7-15*/ 9@+5LZR
package com.adt.service.impl; 8,dBl!G=
O12eH
import java.util.List; g+X}c/".
k4 F"'N
import net.sf.hibernate.HibernateException; Cu6%h>@K$
$1SUU F\.
import org.flyware.util.page.Page; TX
import org.flyware.util.page.PageUtil; SwZA6R&
e{Z &d
import com.adt.bo.Result; EJ2yO@5O
import com.adt.dao.UserDAO; <FZ@Q[RP
import com.adt.exception.ObjectNotFoundException; e}1uz3Rh
import com.adt.service.UserManager; ^pHq66d%Z
},|M9I0
/** HaIM#R32T
* @author Joa qWw\_S
*/ $AHQmyg<
publicclass UserManagerImpl implements UserManager { EqI(|bFwy
=-p$jXVW%
private UserDAO userDAO; 7g_]mG[6
'uy/o)L
/** nB .G
* @param userDAO The userDAO to set. [=~ pe|8:
*/ o6 $4/I
publicvoid setUserDAO(UserDAO userDAO){ sH\5/'?
this.userDAO = userDAO; o.I6ulY8
} l&?ii68/
)=Jk@yj8x
/* (non-Javadoc) y(
y8+ZT
* @see com.adt.service.UserManager#listUser B#9{-t3Vf
@IXsy
(org.flyware.util.page.Page) ->N8#XH2=
*/ zXRlo]
public Result listUser(Page page)throws /hO1QT}xd
orb_"Qw
HibernateException, ObjectNotFoundException { +
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int totalRecords = userDAO.getUserCount(); G8Du~h!!U
if(totalRecords == 0) oY, %Iq
throw new ObjectNotFoundException Nz)l<S9>
{s;U~!3aY
("userNotExist"); ElUEteZ
page = PageUtil.createPage(page, totalRecords); 6uR^%W8]
List users = userDAO.getUserByPage(page); }NB}"%2
returnnew Result(page, users); B$Kn1 k
} "yW:\
7%sdtunf`
} 08*v~(T
-IV]U*4
++E3]X|
Z@r.pRr'
6^DR0sO
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 m4*@o?Ow
G z)NwD
询,接下来编写UserDAO的代码: Po%(~ )S>
3. UserDAO 和 UserDAOImpl: \QB;Ja_
java代码: a0Zv p>Ft
[+P#tIL
jVq(?Gc
/*Created on 2005-7-15*/ 2PG [7u^
package com.adt.dao; /7
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import java.util.List; {26ONa#i
bcupo:N
import org.flyware.util.page.Page; n93=8;&
9YBv|A
import net.sf.hibernate.HibernateException; fDP$ sW
nl9P,
d
/** HJY2#lSha6
* @author Joa CJhL)0Cs
*/ 3)RsLI9
publicinterface UserDAO extends BaseDAO { vY_-Ranj#.
ZWS`\M
publicList getUserByName(String name)throws W|o'&
N
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HibernateException; 2@
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"]G\9b)
publicint getUserCount()throws HibernateException; AQ='|%
\Acqr@D
publicList getUserByPage(Page page)throws Pfs;0}h5
M.>l#4s,'
HibernateException; 'g{9@PkGn
S<J}[I7V
} y\x+
3*@5S]]
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Q1z;/A$Al
C$5[X7'
java代码: %!1Q P[}K
`ta7Gc/:UY
plZ>03(6Q
/*Created on 2005-7-15*/ x)_0OR2lkp
package com.adt.dao.impl; n\Lb.}]1~
l\n@cQR
import java.util.List; kTvd+TP4
9 '2_
import org.flyware.util.page.Page; ERN>don2
wT{nu[=GH*
import net.sf.hibernate.HibernateException; LWt&3
import net.sf.hibernate.Query; /Js7`r=Rx
CH<E,Z
C1T
import com.adt.dao.UserDAO; 3=L.uXVb
Ft!],n-n*
/** Tq~=TSD
* @author Joa vz!s~cAt
*/ h3;bxq!q
public class UserDAOImpl extends BaseDAOHibernateImpl RG4 sQ0
/7YF mI/0
implements UserDAO { YSe.t_K2C
9tqF8pb7v
/* (non-Javadoc) PV=5UyjW
* @see com.adt.dao.UserDAO#getUserByName Gmz6$^D
?pzaG{
(java.lang.String) 5;{H&O9Q
*/ @n": w2^B
publicList getUserByName(String name)throws "T- `$'9
X<*U.=r)
HibernateException { Alxx[l\<J
String querySentence = "FROM user in class eD#hpl
2TA*m{\Hr
com.adt.po.User WHERE user.name=:name"; L5\WpM=
Query query = getSession().createQuery eET}r24
>MvDVPi~+
(querySentence); >HS W]"k
query.setParameter("name", name); Zp#v Hs
return query.list(); XSZ k%_
} Ny%(VI5:
,11H.E
Z
/* (non-Javadoc) :]1TGfS
* @see com.adt.dao.UserDAO#getUserCount() #&7}-"Nd
*/ eh5gjSqx
publicint getUserCount()throws HibernateException { fP `b>]N_
int count = 0; 1N>|yQz
String querySentence = "SELECT count(*) FROM aUtnR<6
uF3qD|I\
user in class com.adt.po.User"; t0T"@t#c
Query query = getSession().createQuery m
RO~aD!N
4%3Mb-#Y]
(querySentence); yT,.z 0
count = ((Integer)query.iterate().next ok4@N @
1{r)L{]
()).intValue(); }7.PH'.8
return count; ;y2/-tL?
} oTuOw|[
.?Gd'Lp
/* (non-Javadoc) se>MQM5 )
* @see com.adt.dao.UserDAO#getUserByPage #"5 Dk#@
aqc?pqM
(org.flyware.util.page.Page) v3jg~"!
*/ $"H{4x`-
publicList getUserByPage(Page page)throws E 0?iXSJ
ZKckAz\#
HibernateException { JQ@E>o7_
String querySentence = "FROM user in class Os1>kwC
n0e1k.A
com.adt.po.User"; Z7?~S2{c
Query query = getSession().createQuery '`uwJ&@
wL:flH@
(querySentence); 3z&Fi;<+j
query.setFirstResult(page.getBeginIndex()) "UJ
S5[7$
.setMaxResults(page.getEveryPage()); & J2M1z%
return query.list(); cu/5$m?xx
} 9*1,!%]
ML>[^F
} W!>.$4Q9
k|H:
9c6gkt9eB
D'Y-6W3
m-*hygkcDu
至此,一个完整的分页程序完成。前台的只需要调用 vCwe'q`1
H"dJ6
userManager.listUser(page)即可得到一个Page对象和结果集对象 iB& 4>+N+
j_.5r&w
的综合体,而传入的参数page对象则可以由前台传入,如果用 t8+X%-r
]@Uq=?%
webwork,甚至可以直接在配置文件中指定。 |VNnOM
nPy$D-L,
下面给出一个webwork调用示例: _<OSqE
java代码: % V8U(z
#Ibp(
2P@sn!*{1
/*Created on 2005-6-17*/ uvG]1m#
package com.adt.action.user; dKxyA"@
_`:1M2=
import java.util.List; csW43&
L=sYLC6d
import org.apache.commons.logging.Log; Nu?-0>
import org.apache.commons.logging.LogFactory; K%RxwM
import org.flyware.util.page.Page; #a8B/-
VN\W]jT
import com.adt.bo.Result; (j3xAA
import com.adt.service.UserService; YS *9t
Q{
import com.opensymphony.xwork.Action; -3=#u_
?qWfup\S
/** @6]sNm
* @author Joa L$E{ycn
*/ 8Hn|cf0
publicclass ListUser implementsAction{ #kaY0M
@dPTk"P
privatestaticfinal Log logger = LogFactory.getLog y3o25}"
io{@^1ab
(ListUser.class); Qh'ATo
1NgCw\
private UserService userService; 9vvx*rD
5E zw
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private Page page; Pf\D-1gi
m4l&
eEp
privateList users; WL?\5?G9l
rcC<Zat,|
/* 2vWx)Drb6
* (non-Javadoc) .Lsavpo
* }%_ b$
* @see com.opensymphony.xwork.Action#execute() \}"$ ?d'f
*/ 9|gr0~j
publicString execute()throwsException{ 2h1vVF3
Result result = userService.listUser(page); t_$2CRG#
page = result.getPage(); "C{}Z
users = result.getContent(); .xm.DRk3
return SUCCESS; vRHd&0
} xk5@d6Y{r
HV{wI1
/** m0;CH/D0
* @return Returns the page. P;ci9vk
*/ +
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public Page getPage(){
c_'OPJ
return page; \Ani}qQ%|
} |m^k_d!d
G2Qlt@.T
/** )W;o<:x3
* @return Returns the users. e'~J,(fB
*/ Hn%xDJ'
publicList getUsers(){ H?&Mbw
d
return users; I J(
} $JMXV
<FcG
oGK
/** ~&7MkkftM
* @param page 06c>$1-?
* The page to set. OHb[qX\
*/ +RYls|f
publicvoid setPage(Page page){ '":lB]hS
this.page = page; ]pNvxXbeW
} 1+jAz`nA:T
qQ?"@>PALD
/** -y8`yHb_
* @param users =E.t`x=
* The users to set. ]%wVHC
*/ N`L0Vd
publicvoid setUsers(List users){ =WyZX 7@R
this.users = users; LE9(fe) fe
} ToXki,
MbZJ;,e?
/** N D(/uyI
* @param userService di6QVRj1
* The userService to set. _/6!yyl
*/ zxbpEJzpn
publicvoid setUserService(UserService userService){ MHX?@.
v
this.userService = userService; $_o-~F2i5
} =}DR)
9
} Rn9m]x
(`c
[#0=n
-bT)]gA2
%yW3VL
ifUGY[ L
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, Z{ X|6.
jB$IyQ;@
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 tG9BfGF
<UV1!2nv*
么只需要: E[@ u
3i8
java代码: $RIecv<e_
t\{'F7
&]v4@%<J
<?xml version="1.0"?> vY${;#~|
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork R`DKu=
Nn~~!q
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ||hb~%JK6
\{Z;:,S
1.0.dtd"> si`A:14R
52 fA/sx
<xwork> Crho=RJPR
%|g>%D3Z?
<package name="user" extends="webwork- TDFkxB>
#LL?IRH9^
interceptors"> _aad=BrMK
k.vBj~xU
<!-- The default interceptor stack name 9F)z4
J'SZ
--> q)S^P>
<default-interceptor-ref }z _
jkiFLtB@V
name="myDefaultWebStack"/> ![YX]+jqNp
5NS[dQG5
<action name="listUser" 9`I _Et
+*ZO&yJQ^<
class="com.adt.action.user.ListUser"> 6y+Kjd/D
<param -@yh>8v
[ sN EHf
name="page.everyPage">10</param> (@<lRA
^
<result 4)h]MOZ
ysxb?6
name="success">/user/user_list.jsp</result> ko.(pb@+
</action> R?~Yp?B^
)0"wB
</package> ,2j&ko1
?Z Rs\+{vG
</xwork> 7
%Oa;]|
<>s`\ %
>}`:Ac
q3.j"WaP
`k[-M2[
Szq/hv=Q
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 L;VoJf
uC+V6;
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。 %{AO+u2i
U3T#6Rptl
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 4
N H
b$ve sJ
<tF9V Jq
;1`fC@rI
1crnmJ!C
我写的一个用于分页的类,用了泛型了,hoho "= 6_V?&w
$@^pAP
java代码: '(f&P=[b
Q1O}ly}JS
4}_j`d/8|
package com.intokr.util; BSYzC9h`
_LMM,!f
import java.util.List; 8YZbP5'
t]y
D-3'l&
/** GN ]cDik
* 用于分页的类<br> ud xZ0
* 可以用于传递查询的结果也可以用于传送查询的参数<br> $ACvV"b
* LJk@Vy <?
* @version 0.01 Q<h-FW8z
* @author cheng eqP&8^HP
*/ ),U X4%K=
public class Paginator<E> { Bg&i63XL$$
privateint count = 0; // 总记录数 :`-,Lbg
privateint p = 1; // 页编号 56+s~hG
privateint num = 20; // 每页的记录数 X%Z{K-
privateList<E> results = null; // 结果 P|.] DJ
i`QKH
/** J8S'/y(LE<
* 结果总数 g .onTFwN
*/ biSz?DJ>
publicint getCount(){ eoai(&o0$
return count; [q/Abz'i
} ?&|5=>u2}$
b%<9Sn
publicvoid setCount(int count){ LV\DBDM
this.count = count; :p]'32FA!
} Qr^|:U!;[z
: YXX8|>
/** &j4 xgh 9
* 本结果所在的页码,从1开始 v%"|WV[N
* SnE(o)Q
* @return Returns the pageNo. 1u:
gFUb
*/ NWM8[dI
publicint getP(){ h3bff#<K
return p; JHz
[ 7
} ]z l[H7
FrTi+& <
/** RoU55mL
* if(p<=0) p=1 EQf[,
* ep2k%?CX 1
* @param p Z @^9PQG$
*/ J3n-`k8
publicvoid setP(int p){ ]}U*_rM:
if(p <= 0) JsDpy{q
p = 1; W#KpPDgZE
this.p = p; `Jzp Sw
} @&X|5p"[g
-7S g62THS
/** Ezr:1 GJ
* 每页记录数量 /lo2y?CS*
*/ `&D|>tiz
publicint getNum(){ i%/Jp[e\W>
return num; LG<J;&41~S
} J@4 Bf
xYmxc9)2
/** ,=Mt`aN
* if(num<1) num=1
|QU <e
*/ }
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publicvoid setNum(int num){ R $&o*K`?
if(num < 1) S<4c
r
num = 1; MrDc$p W G
this.num = num; %kdEun
} $Hj.{;eC/k
}HY-uQ%@g
/** w+yC)Rmz
* 获得总页数 BsEF'h'Owh
*/ hS)'a^FV
publicint getPageNum(){ huJ&]"C
return(count - 1) / num + 1; *QLI3B9V
} b*`lk2oMa/
ZaL.!g
/** 7cTV?nc
* 获得本页的开始编号,为 (p-1)*num+1 w)Q0_2p.
*/ Vl:^>jTki
publicint getStart(){ D'J0wT#
return(p - 1) * num + 1; CbwJd5tk
} #wV8X`g
a'2$nbp}
/** B)qWtMZx
* @return Returns the results. k&,~qoU
*/ Q
aS\(_
publicList<E> getResults(){ G&4&-<
return results; sOU1n
} !"\80LP
J[4mLU
public void setResults(List<E> results){ i70wrW#k
this.results = results; ]=>F.GE
} DP3PYJ%+B
BDR.AZ
public String toString(){
8xccp4
StringBuilder buff = new StringBuilder 3?1`D/
;i<|9{;
(); tE)suU5Y
buff.append("{"); prTw'~(B
buff.append("count:").append(count); FLGk?.x$\
buff.append(",p:").append(p); fpFhn
buff.append(",nump:").append(num); R)mu2^
buff.append(",results:").append [uI|DUlI6o
Bh;7C@dq
(results); @JyK|.b#0
buff.append("}"); vSi.txV2
return buff.toString(); 5 N#3a0)
} )?X-(4
v
8$>rwB
} )i!o8YB
YbTxn="_
H;YP8MoQ