Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ~&F|g2:
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 yM9>)SE5`
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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 5!$sQ@#}D
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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 O7LJ-M
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。 !
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分页支持类: |wQ3+WN|
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java代码: F s=x+8'M
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package com.javaeye.common.util; y!R9)=/M
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import java.util.List; fl9VokAT
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publicclass PaginationSupport { ;pOV; q3j
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publicfinalstaticint PAGESIZE = 30; Bj><0
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privateint pageSize = PAGESIZE; BI*0JKQu
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privateList items;
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privateint totalCount; IuAu_`,Ndi
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privateint[] indexes = newint[0]; O:T
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privateint startIndex = 0; ya^8mp-
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public PaginationSupport(List items, int H]wP\m)
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totalCount){ yENAc sv
setPageSize(PAGESIZE); ?Ov~\[) F
setTotalCount(totalCount); T@#?{eA
setItems(items); %{:pBt:Z
setStartIndex(0); h<$%y(lP
} N`fFYO
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public PaginationSupport(List items, int QLHEzEvf{/
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totalCount, int startIndex){ LN<rBF[_:f
setPageSize(PAGESIZE); @W$ha
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setTotalCount(totalCount); ~Jsu"kr
setItems(items); 88[u^aC
setStartIndex(startIndex); /Ix5`Q)
} F|.tn`j]U
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public PaginationSupport(List items, int y x#ub-A8
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totalCount, int pageSize, int startIndex){ _zzNF93Bn
setPageSize(pageSize); !?+0O]`}
setTotalCount(totalCount); #=ij</
setItems(items); 8No'8(dPX
setStartIndex(startIndex); <6,,:=#
} h>cjRH?e
cT/mi":8{
publicList getItems(){ ;YMg4Cs
return items; 3$5E1*ed
} ?P>4H0@I+
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publicvoid setItems(List items){ CAom4Sp'
this.items = items; K4]ZVMm/*
} `D=`xSEYl
UhkL=+PD
publicint getPageSize(){ O#O"]A
return pageSize; `T7TWv"M
} `l.bU3C
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publicvoid setPageSize(int pageSize){ o&z [d
this.pageSize = pageSize; DS7L}]
} v.>K
)%`#
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publicint getTotalCount(){ U,6sR
return totalCount; \*b
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} YN<vOv
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publicvoid setTotalCount(int totalCount){ 5=<KA
if(totalCount > 0){ ~$j;@4
this.totalCount = totalCount; A<TYt
M
int count = totalCount / Yh@2m9
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pageSize; |42;171
if(totalCount % pageSize > 0) +(afO~9
count++; S+wT}_BQ
indexes = newint[count]; ~%M*@fm
for(int i = 0; i < count; i++){ shy[>\w
indexes = pageSize * )uR_d=B&
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i; Dr=$ }Y
} ~!g2+^G7+P
}else{ Jmg9|g!f
this.totalCount = 0; 1-PlRQs.1
} (3!6nQj-t
} N'aq4okoL
`{
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publicint[] getIndexes(){ k\j_hu
return indexes; .\ya
} WQiRbb X
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publicvoid setIndexes(int[] indexes){ O`GF|
this.indexes = indexes; PE/uB,Wl
} P?n4B \!
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publicint getStartIndex(){ 7l=Tl[n
return startIndex; ~OvbMWu
} $_TS]~y4}
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publicvoid setStartIndex(int startIndex){ +S-60EN*A
if(totalCount <= 0) fR {_P
this.startIndex = 0; nHq4f&(H
elseif(startIndex >= totalCount) +,$pcf<[V
this.startIndex = indexes KfZb=v;-l
YX)Rs
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[indexes.length - 1]; r@vt.t0#
elseif(startIndex < 0) &nI>`Q'
this.startIndex = 0; Qo^(r$BD
else{ 3tJfh=r=1
this.startIndex = indexes !~R<Il|B
Gr/}&+S
[startIndex / pageSize]; 2QAP$f0Ln
} #-+Q]}fB4
} yZgWFf.X
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publicint getNextIndex(){ xDH#K0-#L
int nextIndex = getStartIndex() + w{k ^O7~
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pageSize; Z[]8X@IPe
if(nextIndex >= totalCount) zF>;7'\x
return getStartIndex(); B]()
else |mRlP5
return nextIndex; |j9aTv[`
} ePJ_O~c
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publicint getPreviousIndex(){ WcY_w`*L
int previousIndex = getStartIndex() - 42 lw>gzr!
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@by{
pageSize; L]!![v.VY
if(previousIndex < 0) #ley3rJW]
return0; ~I;x_0iY4
else -Q
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return previousIndex; v7KBYN
} =H;'.!77Hx
*)
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} p'%S{v@5((
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抽象业务类 ">3t+A
java代码: 1i~q~O,
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/** /VufL+q1
* Created on 2005-7-12 :3
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*/ MMpId
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package com.javaeye.common.business; '7oCWHq[
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import java.io.Serializable; GK1nGdT]
import java.util.List; Y*\h?p[,
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import org.hibernate.Criteria; & /T}
import org.hibernate.HibernateException; m;>G]Sbe
import org.hibernate.Session; "!AtS
import org.hibernate.criterion.DetachedCriteria; =SeQ- H#
import org.hibernate.criterion.Projections; !o?&{"#+
import Xa#.GrH6
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org.springframework.orm.hibernate3.HibernateCallback; cb0rkmO
import Ay 4P_>^
!m9hL>5vR
org.springframework.orm.hibernate3.support.HibernateDaoS /!?Tv8TPp
;|?_C8
upport; 6S3D#SY
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import com.javaeye.common.util.PaginationSupport; :Rv+Bm
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public abstract class AbstractManager extends ^gp]tAf
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HibernateDaoSupport { T$R#d&t
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privateboolean cacheQueries = false; f+s)A(?3
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privateString queryCacheRegion; lZ[J1:%
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publicvoid setCacheQueries(boolean .xmB8 R
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cacheQueries){ w@Q~ax/
this.cacheQueries = cacheQueries; L?j<KW
} <\Y(+?+uZ
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publicvoid setQueryCacheRegion(String Et(H6O8
j
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queryCacheRegion){ UYJ>L
this.queryCacheRegion = +}?%w|8||s
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queryCacheRegion; ?Sa,n^b*H
} J(/J;PW
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publicvoid save(finalObject entity){
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getHibernateTemplate().save(entity); Ij.mLO]
} u t4:LHF
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publicvoid persist(finalObject entity){ YlG#sBzl
getHibernateTemplate().save(entity); L xIKH
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} F02TM#Zi
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publicvoid update(finalObject entity){ Yu_
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getHibernateTemplate().update(entity); uE (5q!/
}
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publicvoid delete(finalObject entity){ GBRiU&D
getHibernateTemplate().delete(entity); /|UbYe,
} DBcR1c&<H
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publicObject load(finalClass entity, HDzeotD
@jMo/kO/A
finalSerializable id){ -X7x~x-
return getHibernateTemplate().load uaKbqX
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(entity, id); Z`GEF|eh
} SIR2 Kc0
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publicObject get(finalClass entity, ?f'`b<o
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finalSerializable id){ jCNR63/
return getHibernateTemplate().get Nb_Glf
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(entity, id); f-[.^/
} <b_K*]Z
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publicList findAll(finalClass entity){ ,%xat`d3,3
return getHibernateTemplate().find("from 4f8XO"k7t=
@g;DA)!(
" + entity.getName()); C Q iHk
} UukY9n];]
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publicList findByNamedQuery(finalString z@\mn
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namedQuery){ =+T0[|gc(r
return getHibernateTemplate ,98 F
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().findByNamedQuery(namedQuery); US9aW)8
} x$ TLj
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publicList findByNamedQuery(finalString query, g +gcH
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finalObject parameter){ 9 4lt?|3=
return getHibernateTemplate (yd(ZY
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().findByNamedQuery(query, parameter); %_p]6doF
} h]z 8.k2n
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publicList findByNamedQuery(finalString query, b 1Wz
[]
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finalObject[] parameters){ T8&sPt,f
return getHibernateTemplate u R5h0Fi
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().findByNamedQuery(query, parameters); iY2q^z/S
} ~.U\Y
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publicList find(finalString query){ f]?&R c2C
return getHibernateTemplate().find 06.8m;{N
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(query); ]K>bSK^TX
} z%+rI
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publicList find(finalString query, finalObject ;ud"1wH
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parameter){ "o u{bKe
return getHibernateTemplate().find i-4L{T\K
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(query, parameter); xpuTh"ED
} `#`C.:/n
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public PaginationSupport findPageByCriteria 8
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(final DetachedCriteria detachedCriteria){ 5{1=BZftZ
return findPageByCriteria Zn)o@'{}{
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); \/Q~C!
} M($GZ~ b%A
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public PaginationSupport findPageByCriteria HEa7!h[a'
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(final DetachedCriteria detachedCriteria, finalint ,`a8@
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startIndex){ Y@MxKK uj
return findPageByCriteria UM21Cfqex
'BgR01w J
(detachedCriteria, PaginationSupport.PAGESIZE, z/QYy)_j
(0_zp`)
startIndex); IIBS:&;+-
} x*TJYST
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public PaginationSupport findPageByCriteria j!k$SDA-
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(final DetachedCriteria detachedCriteria, finalint Z]k@pR !
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pageSize, !SGRK01
finalint startIndex){ x=x%F;
return(PaginationSupport) -*T0Cl.
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getHibernateTemplate().execute(new HibernateCallback(){ PX/^*
publicObject doInHibernate K~3Y8ca
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(Session session)throws HibernateException { 3X ',L*f
Criteria criteria = Uy)pEEu
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detachedCriteria.getExecutableCriteria(session); 2*
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int totalCount = D88IU9V&n
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((Integer) criteria.setProjection(Projections.rowCount Z }>;@c
hV)
`e"r\s
()).uniqueResult()).intValue(); N;>s|ET
criteria.setProjection " L,9.b
7,alZ"%W
(null); 4,Uqcw?!F'
List items = fN<Y3^i"
N0\<B-8+,>
criteria.setFirstResult(startIndex).setMaxResults b^}U^2S%
6^BT32,'
(pageSize).list(); Q:y'G9b
PaginationSupport ps = =9p3^:S
o^owv(
new PaginationSupport(items, totalCount, pageSize, m&(qr5>b
pbWjTI $
startIndex); jt* B0'Sa
return ps; q3K}2g
} % hH> %
}, true); Up_"qD6
} W* v3B.
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public List findAllByCriteria(final C,LosAd
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DetachedCriteria detachedCriteria){ #67 7,dn
return(List) getHibernateTemplate %CgV:.,K
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().execute(new HibernateCallback(){ ,\RR@~u'
publicObject doInHibernate (#z6w#CU(
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(Session session)throws HibernateException { ^/x\HGrw
Criteria criteria = Rs"G8Q9Q
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detachedCriteria.getExecutableCriteria(session); vO/ 3bu}
return criteria.list(); AKk&
} HN5,MD[
}, true); SdnO#J}{
} GWWaH+F[h
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public int getCountByCriteria(final :Y9/} b{
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DetachedCriteria detachedCriteria){ 42}8es.aa
Integer count = (Integer) pW>{7pXn
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getHibernateTemplate().execute(new HibernateCallback(){ AUIp
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publicObject doInHibernate WNKP';(a@G
8`]yp7ueS
(Session session)throws HibernateException { ]0|A\bE\S
Criteria criteria = 1_Av_X
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detachedCriteria.getExecutableCriteria(session); iY&I?o!Ch
return E8p,l>6(f
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criteria.setProjection(Projections.rowCount P46Q3EE
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()).uniqueResult(); @A*>lUo
} *8)va
}, true); 8B(v6(h
return count.intValue(); ~$"2,&
} P4/~_$e
} L*vKIP<EMM
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用户在web层构造查询条件detachedCriteria,和可选的 %&V%=-O_7
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 %*Uc,V
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PaginationSupport的实例ps。 -R\dg S3
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ps.getItems()得到已分页好的结果集 E\;%,19Ob
ps.getIndexes()得到分页索引的数组 ~mi4V
ps.getTotalCount()得到总结果数 '!,(G3
ps.getStartIndex()当前分页索引 1v,R<1)&
ps.getNextIndex()下一页索引 uxh>r2Xr=
ps.getPreviousIndex()上一页索引 Eciu^
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 }@tgc?CD
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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 rzLW@k
zEukEA^9`
一下代码重构了。 N>]J$[j
#k`gm)|
我把原本我的做法也提供出来供大家讨论吧: #Q*V9kvU/H
qc\D=3#Yp
首先,为了实现分页查询,我封装了一个Page类: ]6A wd A
java代码: ZKpJc'h
9
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/*Created on 2005-4-14*/ [+xsX*+
package org.flyware.util.page; S9r+Nsn
v_WQ<G?
/** NuD|%Ebs
* @author Joa MxKTKBxQ
* `<M>"~W
*/ RgQs`aI
publicclass Page { `+>K)5hrR
2+~gZxHq
/** imply if the page has previous page */ :Q@/F;Z?
privateboolean hasPrePage; :XG~AR/
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/** imply if the page has next page */ gw[Eu>I
privateboolean hasNextPage; n^O!93a
uN>5Eh&=Pf
/** the number of every page */ h8(>$A-
privateint everyPage; Q>rr?L`
cY kb3(
/** the total page number */ a
}*i [
privateint totalPage; (}.MB3`#C
p3{Ff5FZ
/** the number of current page */ ]t`SCsoo
privateint currentPage; gTU5r4xm~
B.~]
7H5"(
/** the begin index of the records by the current ; D/6e6
iR88L&U>
query */ jC{KI!kPt
privateint beginIndex; ctjQBWE
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/** The default constructor */ '=#fELMW
public Page(){ >8=lX`9f{
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} 9:-7.^`P
}f?[m&<
/** construct the page by everyPage /sT?p=[.
* @param everyPage ctLNzJes%
* */ f% )9!qeW
public Page(int everyPage){ [Z#Sj=z
this.everyPage = everyPage; 5\#I4\
} ~QxW^DGa7]
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/** The whole constructor */ _6ck@
public Page(boolean hasPrePage, boolean hasNextPage, c1jRj=\
LCtVM70
_N^w5EBC]
int everyPage, int totalPage, &r4|WM/ec
int currentPage, int beginIndex){ s*<T'0&w0S
this.hasPrePage = hasPrePage; )`R}@(r.
this.hasNextPage = hasNextPage; Y_!+Y<x7v
this.everyPage = everyPage; Y68A+
B.
this.totalPage = totalPage; gD4vV'|
this.currentPage = currentPage; dpylJ2
this.beginIndex = beginIndex; 3Ke6lV)uq
} m|{^T/kIbQ
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/** =r7!QXPH}
* @return 6kdbbGO-
* Returns the beginIndex. F4==a8
*/ f(~N+2}
publicint getBeginIndex(){ ]7Sf)
return beginIndex; 8(L2w|+B<
} AD?XJ3
M\{\WyeX
/** s hH2/.>
* @param beginIndex js5VgP`
* The beginIndex to set. ,1N|lyV
*/ P~=yTW
publicvoid setBeginIndex(int beginIndex){ |vl~B|",
this.beginIndex = beginIndex; OoH-E.lp
} sVw:d_ E
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/** m:[I$b6AY
* @return p^<(.+P4
* Returns the currentPage. UF#!6"C@
*/ jga \Ry=nw
publicint getCurrentPage(){ /[\g8U{5B}
return currentPage; 1(IZ,*i
} :;]9,n
v
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/** d!0rq4v7
* @param currentPage TPk?MeVy%W
* The currentPage to set. Wtcib-
*/ SM4`Hys;p
publicvoid setCurrentPage(int currentPage){ B\)Te9k'
this.currentPage = currentPage; ;..z)OP_
} b(;u2 8
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/** c:7F
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* @return n-" (~
* Returns the everyPage. ka\{?:r,8
*/ 52tc|j6~#
publicint getEveryPage(){ 0
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return everyPage; L#byYB;E{
}
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__.MS6"N
/** A`f"<W-m
* @param everyPage 8TeOh1\
* The everyPage to set. F!ztU8,
*/ u*)/e9C
publicvoid setEveryPage(int everyPage){ \j62"
this.everyPage = everyPage; "N6HX*
} /u4RZ|&as
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/** ;6[6~L%K}
* @return 8$\j| mN
* Returns the hasNextPage. wPjq
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*/ DMG~56cTO,
publicboolean getHasNextPage(){ /ta}12Z
return hasNextPage; KxX [8
} yef\Y3X
_Ik?WA_;
/** bAZoi0LR
* @param hasNextPage m]>zdP+
* The hasNextPage to set. e!*]y&W
*/ %(/E
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publicvoid setHasNextPage(boolean hasNextPage){ d,98W=7
this.hasNextPage = hasNextPage; .c+U=bV-
} Y|fD)zG_
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/** \~E?;q!
* @return WT<}3(S'?
* Returns the hasPrePage. HdqB B
*/ Bc"MOSV0
publicboolean getHasPrePage(){ P|$n
return hasPrePage; W4^zKnH
} uv/\1N;V3
jj2iF/
/** 6-_g1vq
* @param hasPrePage zY_J7,0g
* The hasPrePage to set. [q2:d^_FA
*/ JfN
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publicvoid setHasPrePage(boolean hasPrePage){ y%i9 b&gDd
this.hasPrePage = hasPrePage; d/Q#Z
} F~
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.))jR:{3
/** 3&^hf^yg
* @return Returns the totalPage. vY m:V:7Y2
* "@eGgQ
*/ /f1]U
LmC:
publicint getTotalPage(){ nD
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return totalPage; t[`LG)
} l'EO@D/M
]i.N'O<p
/** \DQu!l@1U
* @param totalPage <
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* The totalPage to set. 1 Q(KZI
*/ l2St)`K8
publicvoid setTotalPage(int totalPage){ o{,IO!q
this.totalPage = totalPage; FprdP*/
} ]{6/6jl
u>fMO9X}2
} ?;CIS$$r
iN
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w<`0D)mQ
8)1q,[:M
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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 0* F` h
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X[xZGV,
个PageUtil,负责对Page对象进行构造: ~-A"j\gi"
java代码: UF!qp
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/*Created on 2005-4-14*/ RBrb7D{
package org.flyware.util.page; =Q(J!f
hAf/&yA@
import org.apache.commons.logging.Log; R BHDfm'~7
import org.apache.commons.logging.LogFactory; P!+Gwm{
z;1dMQ,#
/** 7?whxi Qs
* @author Joa D5c
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* Q0R05*
*/ MWv@]P_0p!
publicclass PageUtil { a
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privatestaticfinal Log logger = LogFactory.getLog + kKanm[!v
n\((#<&
(PageUtil.class); v@%4i~N
n/5T{ NfG
/** O.B9w+G=
* Use the origin page to create a new page 2/4zg
* @param page wH o}wp
* @param totalRecords 1;( h0j
* @return JW[6
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*/ 6NX#=A
publicstatic Page createPage(Page page, int Gf"TI:xa
(s;W>,~q
totalRecords){ U~][
ph
return createPage(page.getEveryPage(), %cSx`^`6j
$@'BB=i
page.getCurrentPage(), totalRecords); X3}eq|r9
} \:J=tAC
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/** IADHe\.
* the basic page utils not including exception 3Tu]-.
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handler HQP.7.w7 5
* @param everyPage Li6|c*K'
* @param currentPage MMFg{8
* @param totalRecords G*N[t w
* @return page <rE>?zvm
*/ j$q5m 24L
publicstatic Page createPage(int everyPage, int YYn8!FIe
kZG .Id
currentPage, int totalRecords){ d MR?pbD
everyPage = getEveryPage(everyPage); 5=C?,1F$A
currentPage = getCurrentPage(currentPage); kC. !cPd
int beginIndex = getBeginIndex(everyPage, FB?~:7+'
=Mx"+/Yo*
currentPage); 5c]:/9&
int totalPage = getTotalPage(everyPage, 1@p,
u"qVT9C$=
totalRecords); \~*<[.8~
boolean hasNextPage = hasNextPage(currentPage, "M5
C Imp,k0
totalPage); 8Ij<t{Lps
boolean hasPrePage = hasPrePage(currentPage); QZ&(e2z
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returnnew Page(hasPrePage, hasNextPage, Br9j)1;
everyPage, totalPage, <Ja&z M
currentPage, 1+Gq<]@G
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beginIndex); 1M&Lb.J6
} >Y08/OAI.2
jlP*RX
privatestaticint getEveryPage(int everyPage){
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return everyPage == 0 ? 10 : everyPage; `*vO8v
} l48$8Mgrr
'UsR/h5T
privatestaticint getCurrentPage(int currentPage){ `TJhH<z"%
return currentPage == 0 ? 1 : currentPage; @6G)(NGD
} Hq}g1?b
/.0K#J:
privatestaticint getBeginIndex(int everyPage, int >"2jCR$/
i-wRwl4aEF
currentPage){ HZAT_
return(currentPage - 1) * everyPage; 'l^Bb#)"
} vm|u~Yd,s
8S#$'2sT
privatestaticint getTotalPage(int everyPage, int X "7CN Td
iKaX8c,zI
totalRecords){ 8s6[-F5
int totalPage = 0; {*O%A
.9vS4C
if(totalRecords % everyPage == 0) F&6#j
totalPage = totalRecords / everyPage; bBs{PI2(p1
else U*a#{C7"
totalPage = totalRecords / everyPage + 1 ; {%3WHGr%L
"yw{A%J
return totalPage; Jai]z
} e=(Y,e3
{'4#{zmp
privatestaticboolean hasPrePage(int currentPage){ eWDXV-xD
return currentPage == 1 ? false : true; @}4>:\es
} :o^ioX.J
X&zGgP/
privatestaticboolean hasNextPage(int currentPage, +zMhA p
:<P4=P P
int totalPage){ GPHb-
return currentPage == totalPage || totalPage == +
-Rf@
6HCg<_j]
0 ? false : true; q#3T
L<
} %J1'>nI!q
c)#7T<>*'
GG>53}7{
} ^)9/Wz _x
h/tCve3Z
SOR\oZ7
nqH[
y0
[UXVL}tk
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 2B$dT=G
IQ<G.
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 Sk53Lc
bQ>wyA+G&E
做法如下: %EU_OS(u.{
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 F8?,}5j
f0g/`j@Up
的信息,和一个结果集List: n@+?tYk*e
java代码: W\Pd:t
IB#
ua:
"m^gCN}c
/*Created on 2005-6-13*/ qe&|6 M!
package com.adt.bo; ynA_Z^j
75;RAKGi
import java.util.List; Xd:{.AXW
}T.>p#z
import org.flyware.util.page.Page; $Zyuhji^
A]m*~Vj]
/** Cl3vp_
* @author Joa aiX&`
*/ 9c]$d
publicclass Result { vx?KenO}
\9,lMK[b
private Page page; "*#f^/LS
eWqS]cM#
private List content; \{<ml n
D-@6 hWh~
/** Ru`afjc
* The default constructor 5*2hTM!
*/ &]a(5
public Result(){ 8US35t:M
super(); Gs"lmX-{$j
} FMCA~N
W2XWb<QSEV
/** :a Cf@:']
* The constructor using fields yI8O#
* TkTGYh
* @param page fASklcQ
* @param content {s@!N
*/ Ydsnu
public Result(Page page, List content){ Q#yHH]U)X
this.page = page; 1^o})9
this.content = content; 2n>mISy+
} @{qcu\sZ
H%n/;DW
/** j6^.Q/{^
* @return Returns the content. ^kK")+K
*/ pWzYC@_W
publicList getContent(){ sB:e:PK
return content; XC6 |<pru
} I;jH'._k#
br88b`L
/** :@&e~QP(
* @return Returns the page. JGq9RB]D$
*/ @8J*vY =e
public Page getPage(){ G?F!Z"S
return page; Ke^/aGi}O
} IrRy1][Qr
"T /$K
/** y+B iaD!U
* @param content 9*j"@Rm
* The content to set. )X#$G?|Hn
*/ v89tV9O)
public void setContent(List content){ 3U?gw!M>
this.content = content; W!el[@
} G:+D1J]
w@WtW8
p^
/** w`boQ_Ir
* @param page L7 FFa:#
* The page to set. ) 5`^@zx
*/ _Iy)p{y
publicvoid setPage(Page page){ b6e2a/x
this.page = page; HHyN\
} <AVWT+,
} }6u}?>S
'GW~~UhdW
T:'<:*pD
q\P{h ij
7KC2%s#7
2. 编写业务逻辑接口,并实现它(UserManager, CiU^U|~ 'L
qu1! KS
UserManagerImpl) 4%v-)HGh
java代码: P<1&kUZL
4Vj]bm
ve/.q^JeJ
/*Created on 2005-7-15*/ 2bXCFv7}
package com.adt.service; 3NwdE/x\
,|+{C~Ojx
import net.sf.hibernate.HibernateException; t:.X=/02
U>n.+/ss
import org.flyware.util.page.Page; p&XuNk
<!W9EM
import com.adt.bo.Result;
fCb&$oRr!
]$)};8;7W
/** 1iqgTi>
* @author Joa Ktuv
a3=>N
*/ pTQ7woj}
publicinterface UserManager { _NuHz
F+zHgE
public Result listUser(Page page)throws qCk`398W
(Gzq 1+B
HibernateException; Ey&A\
gvjy'Rm
} >0N$R|B&
(F R
K#v @bu:'
sN[<{;K4
LD|T1.
java代码: l
Hu8ADva
+^,&z}(
Ak
}i;!p
Ue$
/*Created on 2005-7-15*/ i[vN3`*B
package com.adt.service.impl; 0}_1ZU
sZa>+
import java.util.List; r_^]5C\
1- GtZ2
import net.sf.hibernate.HibernateException; $KRpu<5i}
YTe8C9eO
import org.flyware.util.page.Page; mk-L3H1@J3
import org.flyware.util.page.PageUtil; tpV61L
0a$hK9BH
import com.adt.bo.Result; ewYk>
import com.adt.dao.UserDAO; KmF+3g~#s
import com.adt.exception.ObjectNotFoundException; k
V'0rb
import com.adt.service.UserManager; vO;:~
"8[Vb#=*e
/** Ip,0C8T`Q
* @author Joa K]U8y$^
*/ f xD|_
publicclass UserManagerImpl implements UserManager { L~M6ca"
Gnqun%
private UserDAO userDAO; (j)>npOd9
<ot%>\C
/** :; 3y^!
* @param userDAO The userDAO to set. FbPoyh
*/ t-hN4WKH_A
publicvoid setUserDAO(UserDAO userDAO){ !\Q/~p'jS
this.userDAO = userDAO; Y,%G5X@S<
} W<H^V"^
ra\2BS)X
/* (non-Javadoc) &2Cu"O'.i
* @see com.adt.service.UserManager#listUser JR/^Go$^
SI l<\
(org.flyware.util.page.Page) q'[yYPDX5x
*/ K@=_&A!
public Result listUser(Page page)throws -QydUr/(o
5~omZ,qe
HibernateException, ObjectNotFoundException { J$Ba*`~!!
int totalRecords = userDAO.getUserCount(); u $T'#p1
if(totalRecords == 0) /#4BUfY
f
throw new ObjectNotFoundException A.S:eQvS%
q1M16qv5
("userNotExist"); CY8=prC
page = PageUtil.createPage(page, totalRecords); 0'y3iar
List users = userDAO.getUserByPage(page); c:`&QDF
returnnew Result(page, users); Y4/ !b
} ?37Kc,o
r`=!4vY2
} !7kca#,X
N5GQ2V
qg-?Z,EB
Xn8r3Nb$A
y$pT5X G
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 (AgM7H0
gcs8Gl2
询,接下来编写UserDAO的代码: DU[vLe|Z
3. UserDAO 和 UserDAOImpl: !bD`2m[Q
java代码: ^,Y#_$oR
\Mod4tQ
$zV[-d
/*Created on 2005-7-15*/
XS"lR |
package com.adt.dao; yu62$d
c_bIadE{
import java.util.List; (A8X|Y
`_&7-;)i*\
import org.flyware.util.page.Page; O!\\m0\e
{-Y% wM8<i
import net.sf.hibernate.HibernateException; 4qEeN-6h
GCPSe A~cx
/** HveOG$pT
* @author Joa (%EhkTb
*/ IE9A _u*
publicinterface UserDAO extends BaseDAO { xk5Z&z
/7<l`RSr
publicList getUserByName(String name)throws KrT+Svm
l<RztzUw
HibernateException; (f|3(u'e?
pVm'XP
publicint getUserCount()throws HibernateException; GKKf#r74
fg1["{\
publicList getUserByPage(Page page)throws snyg
vSy#[9}
HibernateException; @RF!p
{__"Z<
} 6rOd80\
sjV>&eb
!j?2HlIK+
<}$o=>'
8wqHr@}p
java代码: sP5\R#
_(s|@UT#
<ibEo98
/*Created on 2005-7-15*/ L?e N(L
package com.adt.dao.impl; %<w)#eV?
']ussFaQ
import java.util.List; Cuq=>J
?F9:rUyN
import org.flyware.util.page.Page; r9uuVxBD
~vIQ-|8r:
import net.sf.hibernate.HibernateException; (1(dL_?
import net.sf.hibernate.Query; 3Vl?;~ :5
Q<V?rPAcx
import com.adt.dao.UserDAO; *w538Vb
V'4sOn
/** Q}M%
\v
* @author Joa Yvu!Q
*/ \j]i"LpWb
public class UserDAOImpl extends BaseDAOHibernateImpl }?=$?3W
gUB%6v G\I
implements UserDAO { -&*
4~
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/* (non-Javadoc) BV X6
* @see com.adt.dao.UserDAO#getUserByName C-abc+/
;X
]+r$_
(java.lang.String) dk9'C
*/ }Q?,O
publicList getUserByName(String name)throws "-+5`!Y
j\D_Z{m2
HibernateException { |BGQ|7DyG
String querySentence = "FROM user in class hX~d1.]Y
WBgS9qiB
com.adt.po.User WHERE user.name=:name"; OFTyN^([@
Query query = getSession().createQuery }Zue?!KQ
I|*w?i*
(querySentence); 0[JJ
query.setParameter("name", name); p] V
return query.list(); [Az<E3H"
} /L8Q[`;.
*eAsA(;
/* (non-Javadoc) Yp1;5Bbp
* @see com.adt.dao.UserDAO#getUserCount() e:E:"elr]
*/ sF$$S/b
publicint getUserCount()throws HibernateException { B6&;nU>;
int count = 0; %EuJ~;x(Mg
String querySentence = "SELECT count(*) FROM qJ b9JL$s
6.| {l8%r
user in class com.adt.po.User"; :O}= $[
Query query = getSession().createQuery i"~J -{d}
]CD
(querySentence); 'Tni;
count = ((Integer)query.iterate().next m?]XNgT
^#T@NN0T
()).intValue(); ?H\K];
return count; @-9I<)Z/2
} "|yuP1;L
Qx-/t 9`!Z
/* (non-Javadoc) 3: 'eZcM
* @see com.adt.dao.UserDAO#getUserByPage oz(V a!
ab5 a>w6}
(org.flyware.util.page.Page) /*)zQ?N
*/ ~.?,*q7
publicList getUserByPage(Page page)throws pPSmSWD?
=ILE/pC-|
HibernateException { *"\QR>n
String querySentence = "FROM user in class ]uN}n;`12
r%*,pN7O
com.adt.po.User"; LE!xj 0
Query query = getSession().createQuery Tji G!W8
bhqBFiuhH
(querySentence); |kPjjVGF{
query.setFirstResult(page.getBeginIndex()) '%.:97
.setMaxResults(page.getEveryPage()); b!C\J
return query.list(); K!c "g,S
} rz%8Vigb
xx`xDD
} ztcV[{[g
n.&z^&$w\)
K}e%E&|>
/UP&TyZ
;x/do?FbT
至此,一个完整的分页程序完成。前台的只需要调用 ^Oy97Y
?/Bp8q(
userManager.listUser(page)即可得到一个Page对象和结果集对象 )N4!zuSVf
K(
: NshM
的综合体,而传入的参数page对象则可以由前台传入,如果用 X}@^$'W
N?Byp&rqI<
webwork,甚至可以直接在配置文件中指定。 o
gec6u}
5eP8nn.D
下面给出一个webwork调用示例: I8R#EM%C#
java代码: s&UuB1
V*X6 <}
OPVF)@"ptM
/*Created on 2005-6-17*/ $on"@l%U
package com.adt.action.user; By&T59
'MLp*3djF,
import java.util.List; Y.XNA]|
n7g}u
import org.apache.commons.logging.Log; u^HC1r|%
import org.apache.commons.logging.LogFactory; ^U"$uJz!c
import org.flyware.util.page.Page; #NU@7Q[4
P%VEJ5,]b
import com.adt.bo.Result; 5bKBVkJ'
import com.adt.service.UserService; wKxw|Fpn
import com.opensymphony.xwork.Action; Nm;yL
*3.K; Ic;
/** =lB+GS%
* @author Joa '3BBTr%aZ
*/ 7Gwn ,&)
publicclass ListUser implementsAction{ HSXv_
"DN0|%`M/
privatestaticfinal Log logger = LogFactory.getLog SlU?,)J}
d 8YP<"V&
(ListUser.class); MI^@p`s
~s3X&!#
private UserService userService; L|B/'
Q=YIAGK
private Page page; *0vq+C
O;zq(/,-l
privateList users; ?4k/V6n@y
.|\}]O`
/* cQg:yoF
* (non-Javadoc) 4= 7#=F1
* _C`&(?}
* @see com.opensymphony.xwork.Action#execute() z$64Ep#
*/ +D7>$&BD
publicString execute()throwsException{ x*H,eY3
Result result = userService.listUser(page); * {avx
page = result.getPage(); 6,wi81F,}
users = result.getContent(); 2IfcdYG
return SUCCESS; 0d>|2QV
} F9ytU> zh
>:o$h2
/** {}.M(nPtv;
* @return Returns the page. 7+!FZo{?
*/ dC'8orFG+
public Page getPage(){ P 2-^j)
return page; Dq07Z^#'
} F,dPmR
h^QLvOuR
/** u[:-^H
* @return Returns the users. rY?]p Mp
*/ v2Ft=_*G|
publicList getUsers(){ s9# WkDR
return users; PHAM(iC&D
} 7%j1=V/
1U)U {i7j
/** h(~@
nd{
* @param page wH?]kV8Q
* The page to set. aB_~Vh
*/ 2ezk<R5q+
publicvoid setPage(Page page){ nYsB^Nr6
this.page = page; b=L4A,w~a
} Z= +Tw!wR>
;*c8,I;
/** "?*B2*|}`
* @param users ,=a+;D]'
* The users to set. ]F{F+r
*/ $)YalZ
publicvoid setUsers(List users){ "xI70c{
this.users = users; QLm#7ms*y
} t6q7w
d Dg[ry
/** (Sv=R(_s
* @param userService ;W 3#q:
* The userService to set. H\%^n<]#
*/ "g5<j p
publicvoid setUserService(UserService userService){ ge#0Q L0K
this.userService = userService; 5)c B\N1u
} Lo<WK
} ?]%ZJd
>b7Yk)[%
xe4`D>LUo
9^?2{aP%
ZGw6Bd_I
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, %!\iII
+@^FUt=tq
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 :
uxJGx
(.J6>"K<
么只需要: M!`&Z9N
java代码: 01n7ua*XX
f8?hEa:js
eK[9wEdn
<?xml version="1.0"?> H2S/!Q;K
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork [-0=ZKH?
RRb>]oD
1.0//EN" "http://www.opensymphony.com/xwork/xwork- H73 r3BH
Pk3b#$+E
1.0.dtd"> ^/ff)'.J
79z/(T+
<xwork> t`-
[
'WNq/z"X
<package name="user" extends="webwork- tjLG$M1z`
v8"Zru
interceptors"> z8dBfA<z
'F%h]4|1
<!-- The default interceptor stack name ;S9
z@`a.
XZ=%XB:?
--> M?00n< vM
<default-interceptor-ref n v
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Ofc
u4pi
name="myDefaultWebStack"/> /pC60y}O0
:-Wh'H(
<action name="listUser" HPY;UN
gXj3=N(l
class="com.adt.action.user.ListUser"> j.yh>"de
<param
/s~BE ,su
6/.kL;AI
name="page.everyPage">10</param> U6F7dT
<result sis1Dh9:
c;,-I
name="success">/user/user_list.jsp</result> b{CS1P
</action> %0zp`'3Y
mKLWz1GZ
</package> cte
Wl/v
12V-EG i
</xwork> M_O) w^
'
~#dfZa&
*EPJeblAV
6o1[fr
9T\\hM)k
!S'!oinV
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 8{
+KNqz
cpm *m"Nk
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 o?d`o$
L@S1C=-/
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 R].xT-1
@dn&M9Z
><C9PS@
;>%wf3e
gSHN,8.
`
我写的一个用于分页的类,用了泛型了,hoho RNopx3
',1[rWyc
java代码: \('WS[$2
?^ R"a##
`[&%fTW+
package com.intokr.util; Z kBWVZb
50dx[v8
import java.util.List; R"{P#U,HNO
$T_>WUiK
/** ? r}2JHvN
* 用于分页的类<br> ( m7qc
* 可以用于传递查询的结果也可以用于传送查询的参数<br> :<H4hYt2
* N>iNz[a
q
* @version 0.01 \D-X
_.v
* @author cheng _=9m[
*/ wn.UjxX.
public class Paginator<E> { \"X_zM
privateint count = 0; // 总记录数 @ %o'
privateint p = 1; // 页编号 mMT\"bb'
privateint num = 20; // 每页的记录数 ba)hWtenH
privateList<E> results = null; // 结果 tqpSir
u
p]>UX8
/** /A-VT
* 结果总数 P\h1%a/D
*/ oz%{D@CF
publicint getCount(){ 7e[&hea
return count; RJ-J/NhWyI
} jw)c|%r>
`*xSn+wL`_
publicvoid setCount(int count){ <Wd_m?z
this.count = count; BO+to.
} S
rhBU6K
TCK#bJ
/** {]iM5?
* 本结果所在的页码,从1开始 5'[yw:P-8
* )1g\v8XT
* @return Returns the pageNo. ~lbm^S}-
*/ R ^"*ut
publicint getP(){ @o&UF-=MW(
return p; +.v+Opp,
} O' Mma5
@P">4xVX{
/** M
9 N'Hk=
* if(p<=0) p=1 EL6<%~,V"I
* As??_=>4
* @param p W]D+[mpgK
*/ `69xR[f
publicvoid setP(int p){ u~!Pzz3"
if(p <= 0) \Hu?K\SWs
p = 1; zpy&\#Vc
this.p = p; }vZTiuzC
} KDr)'gl&
V$ho9gQ!l[
/** k;<F33v;Mh
* 每页记录数量 xv7nChB
*/ XvZ5Q
publicint getNum(){ R8|FqBs
return num; Yez
} aW#^@||B
-h 21
/** ?SX0e(+}}
* if(num<1) num=1 1]aya(
*/ ,w,)n^
publicvoid setNum(int num){ +$R%Vbd
if(num < 1) _@Y17L.
num = 1; LbnF8tj}h
this.num = num; 'EB5#
} b{,vZhP-
j?(@x>HA
/** ,U fB{BW
* 获得总页数 RPkOtRKL=w
*/ DCgiTT\
publicint getPageNum(){ 7??j}ob>
return(count - 1) / num + 1; E6xWo)`%5s
} hOe$h,E']
q X]ej2
/** _<jccQ
* 获得本页的开始编号,为 (p-1)*num+1 Mvk#$:8e
*/ %p};Di[V
publicint getStart(){ !^3j9<|@'
return(p - 1) * num + 1; Y|<1|wGG
} ROj=XM:+
J!:v`gb#@A
/** h)T-7b
* @return Returns the results. F5<GGEQb
*/ _p| KaT``
publicList<E> getResults(){ gWy2E;"a
return results; [jF\"#A
} $I a-go2W
^Y^5 @x=
public void setResults(List<E> results){ NTSKmCvQG
this.results = results; HgRfMiC
} ]2xoeNF/W{
BtP*R,>
public String toString(){ [,qb)
&_
StringBuilder buff = new StringBuilder DO?
bJ01
=e]Wt/AQ
(); ]K%D$x{+\
buff.append("{"); 8;P_KRaE
buff.append("count:").append(count); _1?Fyu&<5
buff.append(",p:").append(p); |9
4xRC
buff.append(",nump:").append(num); nmrdqSV
buff.append(",results:").append @3>nVa
!7anJl
(results); MM Nz2DEy[
buff.append("}"); D"n
3If%
return buff.toString(); dUpOg{I.x
} B'D4]EB
\8SHX
} WR>2t&;E
,DbT4Ul c
Vt
U