Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Q59suL
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 TpaInXR
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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 <aw[ XFg
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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 qK+5NF|
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分页支持类: Wqnc{oq|$
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java代码: PnTu
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package com.javaeye.common.util; &m3lXl
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import java.util.List; dr(*T
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publicclass PaginationSupport { "%_+-C<L4
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publicfinalstaticint PAGESIZE = 30; gR**@t=;j
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privateint pageSize = PAGESIZE; #E?4E1bnB
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privateList items; \+etCo
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privateint totalCount; `uFdwO'DD
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privateint[] indexes = newint[0]; #spCtZE
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privateint startIndex = 0; ^~dWU>
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public PaginationSupport(List items, int x:;kSh
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totalCount){ e(sk[guvX
setPageSize(PAGESIZE); bOB\--:]
setTotalCount(totalCount); 7/H)Az@i45
setItems(items); uH]OEz\H'
setStartIndex(0); _w{Qtj~s|
} !VJoM,b8
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public PaginationSupport(List items, int 1x)J[fyId
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totalCount, int startIndex){ D-c4EV
setPageSize(PAGESIZE); w(/S?d
setTotalCount(totalCount); b-DvW4B
setItems(items); YVU7wW,1
setStartIndex(startIndex); 3Ul*QN{6
} S!UaH>Rh
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public PaginationSupport(List items, int M7T5
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totalCount, int pageSize, int startIndex){ Sf'CN8
setPageSize(pageSize); I0-MRU~[K
setTotalCount(totalCount); %{|p j
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setItems(items); \<' ?8ri#
setStartIndex(startIndex); L#J1b!D&<6
} fl(wV.Je|
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publicList getItems(){ s#11FfF`
return items; o4X{L`m
} Wc#24:OKe3
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publicvoid setItems(List items){ 6t$8M[0-U
this.items = items; khe}*y
} \85i+q:LuA
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publicint getPageSize(){ e=
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return pageSize; yAt^;
} WJ#[LF!e
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publicvoid setPageSize(int pageSize){ A&VG~r$
this.pageSize = pageSize; Ytkv!]"
} k:;r2f
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publicint getTotalCount(){ v+XJ*N[W
return totalCount; (HVGlw'`
} vzM^$V
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publicvoid setTotalCount(int totalCount){ ueudRb
if(totalCount > 0){ G[=c
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this.totalCount = totalCount; pP_LR
ks}
int count = totalCount / b=vkiO`2
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pageSize; )pa]ui\t
if(totalCount % pageSize > 0) ~}P,.QQ
count++; &ncvGDGi
indexes = newint[count]; ]G\}k
for(int i = 0; i < count; i++){ AH^/V}9H
indexes = pageSize * w<#!h6Y=
+[VXs~I
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} !g[Zfo2r"
}else{ V88p;K$+
this.totalCount = 0; vaLSH
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} *w&e\i|7
} ;uJMG
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publicint[] getIndexes(){ Hs8>anVo[
return indexes; &yg|t5o
} V!Uc(
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publicvoid setIndexes(int[] indexes){ &
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this.indexes = indexes; ZVBXx\{s
} KO [Yi
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publicint getStartIndex(){ COlqcq'qAu
return startIndex; *@5 @,=d
} 7#XzrT]
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publicvoid setStartIndex(int startIndex){ IxU/?Zm
if(totalCount <= 0) 0B2t"(&
this.startIndex = 0; 4x34u}l
elseif(startIndex >= totalCount) %J(:ADu]
this.startIndex = indexes I9Xuok!0>=
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[indexes.length - 1]; 9*gZ-#
elseif(startIndex < 0) jA1+x:Wq
this.startIndex = 0; -n
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else{ P:c w|Q
this.startIndex = indexes M3\AY30L
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[startIndex / pageSize]; N8jIMb'<
} <~)P7~$d?p
} k[xSbs'D
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publicint getNextIndex(){ pBHRa?Y5
int nextIndex = getStartIndex() + x5Bk/e'
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pageSize; >:-$+I
if(nextIndex >= totalCount) (`^1Y3&2
return getStartIndex(); 04ui`-c(
else }2jn[${ pr
return nextIndex; @d'j zs
} e'~3oqSvR
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publicint getPreviousIndex(){ 7!1S)dup
int previousIndex = getStartIndex() - ytImB`'\
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pageSize; ?<!|
if(previousIndex < 0) oH@78D0A
return0; |yCMt:Hk
else 6k%f
return previousIndex; e~OpofJNb
} 2y4bwi
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} 5pX6t
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抽象业务类 |!ELV7?(
java代码: "oyo#-5z
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/** .-zom~N-?
* Created on 2005-7-12 yi[x}ffdE
*/ Rq -ZL{LR7
package com.javaeye.common.business; -"x$ZnHU
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import java.io.Serializable; 0GwR~Z}Z
import java.util.List; 43cE`9~
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import org.hibernate.Criteria; KNl$3nX
import org.hibernate.HibernateException; 0GL M(JmK
import org.hibernate.Session; ~%oR[B7=|
import org.hibernate.criterion.DetachedCriteria; Eci\a]
import org.hibernate.criterion.Projections; P55fL-vo|}
import PCA4k.,T
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org.springframework.orm.hibernate3.HibernateCallback; C!gZN9-
import F|8&
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org.springframework.orm.hibernate3.support.HibernateDaoS gGYKEq{j(
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upport; T{"(\X$
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import com.javaeye.common.util.PaginationSupport; )X7A
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public abstract class AbstractManager extends Z+SRXKQ
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HibernateDaoSupport { y =@N|f!
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privateboolean cacheQueries = false; 6)J#OKZ
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privateString queryCacheRegion; /Oono6j
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publicvoid setCacheQueries(boolean +ZYn? #IQ
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cacheQueries){ !-bB559Nv
this.cacheQueries = cacheQueries; 2wn2.\v M
} `cO:<^%
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publicvoid setQueryCacheRegion(String xw%0>K[
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queryCacheRegion){ 1C.VnzRnJ
this.queryCacheRegion = :UdF
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queryCacheRegion; `oJ [u:b
} 2%1hdA<
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publicvoid save(finalObject entity){ ~[: 2I
getHibernateTemplate().save(entity); t^HRgY'NjM
} *j=%
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publicvoid persist(finalObject entity){ |ZBw<f
getHibernateTemplate().save(entity); *:1ey{w:
} y(Td/rY.
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publicvoid update(finalObject entity){ E7hhew
getHibernateTemplate().update(entity); zDp 2g)
} w!CNRtM:~
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publicvoid delete(finalObject entity){ B!yr!DWv
getHibernateTemplate().delete(entity); dx]>(e@(t{
} /?!u{(h }
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publicObject load(finalClass entity, q4q6c")zp
@x1-!
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finalSerializable id){ PH"%kCI:
return getHibernateTemplate().load $(
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(entity, id); V :eD]zq5
} =43auFY-P
@o^Ww
publicObject get(finalClass entity, ;jPXs
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finalSerializable id){ AGno6g
return getHibernateTemplate().get D$N/FJ8|G
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(entity, id); _wcNgFx
} .pq%?&
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publicList findAll(finalClass entity){ \jA~9
return getHibernateTemplate().find("from +"(jjxJm
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" + entity.getName()); #g=XUZ/"
} S'14hk<
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publicList findByNamedQuery(finalString *VeRVaBl
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namedQuery){ bcR_E5x$
return getHibernateTemplate H"KCK6
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().findByNamedQuery(namedQuery); -8Xf0_
} +#By*;BJ
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publicList findByNamedQuery(finalString query, ]9XDS[<2`
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finalObject parameter){ :EH=_"
return getHibernateTemplate /bEAK-
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().findByNamedQuery(query, parameter); r/sNrB1U"y
} U&xUfBDt
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publicList findByNamedQuery(finalString query, q=G+Tocv
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finalObject[] parameters){ .2pK.$.
return getHibernateTemplate 2%>FR4a
j9,P/K$:w
().findByNamedQuery(query, parameters); K#xvu1U
} 6#yUc_5 \
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publicList find(finalString query){ AEuG v}#
return getHibernateTemplate().find )i<j XZ:O
eq" ]%s
(query); Ug`djIL
} ^&)|sP
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publicList find(finalString query, finalObject bfO=;S]b!
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parameter){ ]{ kPrey
return getHibernateTemplate().find HqTjl4ai
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(query, parameter); nd(S3rct&
} .KC++\{HE
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public PaginationSupport findPageByCriteria m3ff;,
{^'HL
(final DetachedCriteria detachedCriteria){ 8] ikygt"
return findPageByCriteria J=L5=G7(
?}7p"3j'z
(detachedCriteria, PaginationSupport.PAGESIZE, 0); -F92 -jBM4
} 66 Tpi![
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public PaginationSupport findPageByCriteria ^J d
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(final DetachedCriteria detachedCriteria, finalint zT[!o
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startIndex){ LF7SS;&~f
return findPageByCriteria b[7]F
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(detachedCriteria, PaginationSupport.PAGESIZE, Df#l8YK#
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startIndex); &OBkevg
} MW{8VH6+
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public PaginationSupport findPageByCriteria XUw/2"D'?
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(final DetachedCriteria detachedCriteria, finalint c"Sq~X
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pageSize, .~}1+\~5
finalint startIndex){ 'RRE|L,
return(PaginationSupport) }75e:w[
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getHibernateTemplate().execute(new HibernateCallback(){ E E'!|N3
publicObject doInHibernate E"@wek.-
= f i$}>\
(Session session)throws HibernateException { Z/K{A`
Criteria criteria = sC ;+F*0g
?s _5&j7
detachedCriteria.getExecutableCriteria(session); L6LZC2N+2
int totalCount = ]~nKK@Rw
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((Integer) criteria.setProjection(Projections.rowCount :yjFQ9^?&
;GhNKPY
()).uniqueResult()).intValue(); 7)k\{&+P
criteria.setProjection km40qO@3
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(null); F>cv<l
=6l
List items = @K]|K]cby
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criteria.setFirstResult(startIndex).setMaxResults :lzrgsW
_? OG1t!
(pageSize).list(); JG,%qFlk
PaginationSupport ps = MWL%
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new PaginationSupport(items, totalCount, pageSize, 63A.@mL
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startIndex); 7=DdrG<
return ps; >U3cTEs cj
} RGU\h[
}, true); A4ygW:
} `#gie$B{
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public List findAllByCriteria(final veRm2LSP
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DetachedCriteria detachedCriteria){ +U.I( 83F
return(List) getHibernateTemplate ]cN1c}
~= -RK$=
().execute(new HibernateCallback(){ F3N6{ysK#
publicObject doInHibernate BCcjK6'
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(Session session)throws HibernateException { VQ{fne<
Criteria criteria = +'@Dz9:>
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detachedCriteria.getExecutableCriteria(session); EyLu O-5
return criteria.list(); FEVlZ<PW3I
} .%OR3"9@
}, true); -R6)ROGl
} TuYCR>P[
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public int getCountByCriteria(final 4,0{7MLgK
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DetachedCriteria detachedCriteria){ h65-s
Integer count = (Integer) 65m"J'
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getHibernateTemplate().execute(new HibernateCallback(){ \r>6`-cs]
publicObject doInHibernate k: ;WtBC6j
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(Session session)throws HibernateException { pU7lnS[
Criteria criteria =
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detachedCriteria.getExecutableCriteria(session); r(2uu
return Lu0x
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criteria.setProjection(Projections.rowCount $DUZ!zaH!
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()).uniqueResult(); 7`hP?a=
} &(mR>
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}, true); -FCe:iY! A
return count.intValue(); !&Pui{F
} D#/Bx[
} [ps*uva
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用户在web层构造查询条件detachedCriteria,和可选的 I15{)o(8$
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 t@Nyr&|D
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PaginationSupport的实例ps。 P}G+4Sk
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ps.getItems()得到已分页好的结果集 8Dm%@*B^b
ps.getIndexes()得到分页索引的数组 K:Q<CQ2
ps.getTotalCount()得到总结果数 BFJnV.0M!
ps.getStartIndex()当前分页索引 [R7Y}k:9U
ps.getNextIndex()下一页索引 s&!a
ps.getPreviousIndex()上一页索引 '-/xyAzS
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 W1FI mlXS
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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 }k
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一下代码重构了。 N<KS(@v
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我把原本我的做法也提供出来供大家讨论吧: *~j@*{u
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首先,为了实现分页查询,我封装了一个Page类: *%t^;&x?
java代码: M>8A\;"
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/*Created on 2005-4-14*/ r s?R:+
package org.flyware.util.page; Y,e B|
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/** Uwx
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* @author Joa Y0K[Sm>
* ?vHU#
*/ :+|Z@KB
publicclass Page { [o5Hl^
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/** imply if the page has previous page */ 8d-t|HkN
privateboolean hasPrePage; M b1sF
M*HnM(
/** imply if the page has next page */ f\>M'{cV
privateboolean hasNextPage; "E?2xf|.
Hi`//y*92H
/** the number of every page */ @)&=%
privateint everyPage; n%s]30Xs
"?I y (*^
/** the total page number */ xDoC(
privateint totalPage; JOLaP@IPT
cFnDmtI:
/** the number of current page */ l.bYE/F0&
privateint currentPage; pWsDzb6?%
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/** the begin index of the records by the current T+K):ug
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query */ 8j\cL'
privateint beginIndex; \:ak ''
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/** The default constructor */ zEy N)
public Page(){ 8j %Tf;
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} !pdb'*,n
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/** construct the page by everyPage 5m(^W[u `
* @param everyPage Q &K
* */ rOOT8nkR#
public Page(int everyPage){ I4q9|'-yx
this.everyPage = everyPage; ,lA s
} 6@0OQb
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/** The whole constructor */ vucxt }Ti
public Page(boolean hasPrePage, boolean hasNextPage, Om@C
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!~D}/Q;#}\
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int everyPage, int totalPage, }m;,Q9:+m^
int currentPage, int beginIndex){ o-OHjFfB
this.hasPrePage = hasPrePage; iv;Is[<o
this.hasNextPage = hasNextPage; M`i\VG
this.everyPage = everyPage; {I #]@,
this.totalPage = totalPage; mFaZio0GK
this.currentPage = currentPage; D(RTVef
this.beginIndex = beginIndex; ^y1j.M@q
} /M4{Wc
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/** YLv'43PL
* @return m(#LhlX
* Returns the beginIndex. ?fjuh}Q5h
*/ #[~pD:qqM
publicint getBeginIndex(){ /}
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return beginIndex; 7 Vo$(kj
} kB|B
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/**
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* @param beginIndex D9
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* The beginIndex to set. MET' (m
*/ $79=lEn,
publicvoid setBeginIndex(int beginIndex){ iQ
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this.beginIndex = beginIndex; C3],n
} ~SF<,-Kg
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/** lXiKY@R#
* @return P5nO78
* Returns the currentPage. ]?
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*/ ?_vakJ
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publicint getCurrentPage(){ 4^~(Mh- Mw
return currentPage; OFv%B/O
} TQ*1L:X7M&
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/** 48qV>Gwf
* @param currentPage &c:Ad%
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* The currentPage to set. #( jw!d&
*/ ,5,!es@`b
publicvoid setCurrentPage(int currentPage){ /.M N
this.currentPage = currentPage;
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} U4-g^S[
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/** 4?7W+/~<&
* @return ytoo~n
* Returns the everyPage. ps%q9}J
*/ `t9?=h!
publicint getEveryPage(){ dEA6
return everyPage; O6/f5
} 4VCOKx
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/** An"</;HU
* @param everyPage VG5+CU
* The everyPage to set. gy0haW
*/ Vz)`nmO}5\
publicvoid setEveryPage(int everyPage){ #Xb+`'
this.everyPage = everyPage; &<J[Q%2
} WIf0z#JMJm
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/** /8g^T")
* @return Q&g^c2
* Returns the hasNextPage. x`mN U
*/ {{MRELipW
publicboolean getHasNextPage(){ DRgTe&+
return hasNextPage; ul2")HL];
} &twf,8
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/** ^Z#W_R\l
* @param hasNextPage V<@ o<R
* The hasNextPage to set. k"]dK,,
*/ _/!y)&4"
publicvoid setHasNextPage(boolean hasNextPage){ ;z:UN}
this.hasNextPage = hasNextPage; vIwCJN1C
} :1^R9yWA4
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/** b7tOo7a H)
* @return : b~6i%b
* Returns the hasPrePage. U1RpLkibQ
*/ QxOjOKAG
publicboolean getHasPrePage(){ rKf-+6Na
return hasPrePage; oifv+oY
} kO{s^_qR^c
/)(#{i*
/** BT"42#7_
* @param hasPrePage aKuSd3E@#
* The hasPrePage to set. h{p=WWK
*/ >ByXB!Wi+
publicvoid setHasPrePage(boolean hasPrePage){ aZ'Lx:)R
this.hasPrePage = hasPrePage; p2udm! )J
} y+6o{`0
pg%aI,
/** )>-ibf`#?
* @return Returns the totalPage. K7Wk6Aw
* ux3<l +jv^
*/ wG<(F}VX
publicint getTotalPage(){ :!b'Vk
return totalPage; 5<j%EQN|D
} FR!? #!
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/** ,|plWIl~
* @param totalPage bk^TFE1l
* The totalPage to set. GJp85B!PlO
*/ FMkzrs
publicvoid setTotalPage(int totalPage){ .]7Qu;L
this.totalPage = totalPage; z;wELz1L{
} wz.6du6-
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} {aJJ`t
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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 nn9wdt@.]
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个PageUtil,负责对Page对象进行构造: T%n2$
java代码:
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/*Created on 2005-4-14*/ 3lq Mucr
package org.flyware.util.page; j"@93D~
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import org.apache.commons.logging.Log; `TPOCxM Mo
import org.apache.commons.logging.LogFactory; dVo.Czyd
8Bq!4uq\5|
/** \7
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* @author Joa :C8$Xi_i}
* h"[+)q%L
*/ %-AE]-/HI
publicclass PageUtil { Yl$SW;@
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privatestaticfinal Log logger = LogFactory.getLog tpTAeQ*:d
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(PageUtil.class); D'hW|
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/** wgRsZ
* Use the origin page to create a new page T}=>C+3r
* @param page awUx=%ERtA
* @param totalRecords 4~OQhiJ
* @return R?EASc!b
*/ }AvcoD/b
publicstatic Page createPage(Page page, int !!nuAQ"E[
h<\_XJJ
totalRecords){ H<G4O02i_
return createPage(page.getEveryPage(), 3TZ*RPmFRm
kY&h~Q
page.getCurrentPage(), totalRecords); =@5x"MOz
} Iu35#j
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/** )CS.F=
* the basic page utils not including exception `K
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oo$MWN8a>r
handler aRJ>6Q}
* @param everyPage ?P7]u>H
* @param currentPage <(e8sNe
* @param totalRecords |J~eLh[d
* @return page CCGV~e+
*/ ACK1@eF
publicstatic Page createPage(int everyPage, int }V|{lvt.
@v*/R%rv t
currentPage, int totalRecords){ 5Fm=/o1
everyPage = getEveryPage(everyPage); |uH%6&\
currentPage = getCurrentPage(currentPage); Px>va01n
int beginIndex = getBeginIndex(everyPage, Q9`QL3LQD
a%Jx
`hx
currentPage); 5Y3i|cj
int totalPage = getTotalPage(everyPage, -sMyt HH.
8g>b
totalRecords); [!VOw@uz
boolean hasNextPage = hasNextPage(currentPage, Sj(F3wY
6R29$D|HFO
totalPage); *AIEl"29
boolean hasPrePage = hasPrePage(currentPage); !"TZ:"VZU
Ij'NC C
returnnew Page(hasPrePage, hasNextPage, 47T}0q,
everyPage, totalPage, ^-M^gYBR
currentPage, ._96*r=o
a/uo}[Y
beginIndex); ag4`n:1
} i$KpDXP\
OlQ,Ce
privatestaticint getEveryPage(int everyPage){ S|GWcSg
return everyPage == 0 ? 10 : everyPage; '?yCq$&
} Ab1/.~^
FCc=e{
privatestaticint getCurrentPage(int currentPage){ -6Mm#sX
return currentPage == 0 ? 1 : currentPage; B )JM%r
} O;]?gj 1@
Sb:T*N0gS
privatestaticint getBeginIndex(int everyPage, int vG2b:[W
<39!G7ny
currentPage){ lKEa)KF[
return(currentPage - 1) * everyPage; Y#01o&f0n
} kDz>r#%
yO>V/5`
privatestaticint getTotalPage(int everyPage, int V8z`qEPM
7e&\{*
totalRecords){ m$$?icA
int totalPage = 0; s-VSH
fH8!YQG8$
if(totalRecords % everyPage == 0) &VWlt2-R0h
totalPage = totalRecords / everyPage; Cv=GZGn-
else Ok%}|/P4
totalPage = totalRecords / everyPage + 1 ; '?GQ~Bf<>
^`qPs/b
return totalPage; em]xtya
} !@
YXZ
nD,{3B#
privatestaticboolean hasPrePage(int currentPage){ ;</Twm;:
return currentPage == 1 ? false : true; y^FOsr
} emA!Ew(g
YJ2ro-X
privatestaticboolean hasNextPage(int currentPage, []&(D_e"
qA/bg
int totalPage){ ^i:\@VA:
return currentPage == totalPage || totalPage == ]R_G{%
I&1!v8
0 ? false : true; C/v}^#cLD
} |&hU=J
o
0D)`2W
Z]-WFU_
N
} s!6=|SS7
p#_[
`!w^0kZ
8t.dPy<
8HoP(+?
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 qvLDfN
C 7nKk/r
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 !g0cC.'
XSB8z
做法如下: ?(im+2
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 amB@N6*
|tG+iF@4
的信息,和一个结果集List: T 0 FZ7
java代码: 9[|4[3K
(buw^
,NwZ
< `Z%O<X
/*Created on 2005-6-13*/ cINHH !v
package com.adt.bo; IF?xnu
-WT3)On
import java.util.List; e!o(g&wBj
cj(X2L
import org.flyware.util.page.Page; hswTn`f
<FmBa4ONU
/** #Mi|IwL
* @author Joa ^&:'NR
*/ O2H/rFx4
publicclass Result { c)1=U_6 1
wR7aQg
private Page page; c d%hW
_@ i>s,
private List content; AQci,j"
$ly0h W
/** }~*rx7p
* The default constructor lvufk VG|
*/ XN;/nU
public Result(){ pVOI5>f\
super(); ?*K<*wBw#
} ,ZK]i CGk
i f@W
]%
/** iUNnPJh
* The constructor using fields 5a$$95oL
* #O</\|aH)i
* @param page !s-/0ugZ
* @param content w<d*#$[,*
*/ *:QXz<_x+
public Result(Page page, List content){ piu0^vEEH
this.page = page; 8!j=vCv
this.content = content; 31 ]7z
} 4Vx+[8W
9U10d&M(
/** YY!!<2_
* @return Returns the content. ~.Q4c*_b
*/ h3h8lt_|
publicList getContent(){ P{lh)m>
return content; j<$R4A1
} f8!l7{2%q
sfC@*Y2XT
/** ;Prg'R[o;
* @return Returns the page. 2k3 z'RLG
*/ [s %\.y(q
public Page getPage(){ y#r\b6
return page; 6{^*JC5nj
} cMtJy"kK
Mw|SH;nM
/** #KJZR{
* @param content ' PL_~
* The content to set. s?<!&Y
*/ 3*\8p6G
public void setContent(List content){ i;HH !
TaN
this.content = content; V~c(]K)-
} 0|Q.U
jf7pl8gv
/** Y\>\[*.v
* @param page !47A$sQ
* The page to set. 'WzUu MCx
*/ Q=XA"R
publicvoid setPage(Page page){ t>@yv#
this.page = page; D'?]yyrf
} \I
xzdFF#
} Wy,"cT
w#d} TY
0hZxN2r
>%i9 oI<)
Dtt\~m;AR
2. 编写业务逻辑接口,并实现它(UserManager, j@V$Mbv
r
&c_4%y
UserManagerImpl) [+7"{UvT
java代码: Fi k@hu
Q^ q=!/qQ
j%GbgJ
/*Created on 2005-7-15*/ {"\q(R0
package com.adt.service; N
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7rPLnB]
import net.sf.hibernate.HibernateException; PoY>5
@d
P~X
import org.flyware.util.page.Page; Z#LUez;&t#
EUXV/QV{
import com.adt.bo.Result; }*ODM6
Z
c<]^QR
/** z}mvX.j7
* @author Joa ?PYNE
*/ V!}L<cN
publicinterface UserManager { yx 7loy$[
;HT0w_,
public Result listUser(Page page)throws XNK
43fkB.
e)br`CD%
HibernateException; M;> ha,x
cnC_#kp
} {!g?d<*
Xv]*;Bq:SK
hX %s]"
TR|;,A[%v#
ZG!x$yi$
java代码: R$v i!0
_=)!xnYf
;,FT&|3o
/*Created on 2005-7-15*/ O<Jwaap
package com.adt.service.impl; 4g S[D
7!mJhgGc
import java.util.List; 9c:5t'Qt5.
I S.F
import net.sf.hibernate.HibernateException; 4'_L W?DS
s"#CkG
import org.flyware.util.page.Page; M$gvq:}kt
import org.flyware.util.page.PageUtil; my=*zziN
?!_u,sT
import com.adt.bo.Result; YlG;A\]k
import com.adt.dao.UserDAO; E#8J+7
import com.adt.exception.ObjectNotFoundException; .!!79 6hS
import com.adt.service.UserManager; \8
g.
1k0^6gE|
/** xqU^I5Z
* @author Joa -fhAtxkg
*/ jDFp31_X
publicclass UserManagerImpl implements UserManager { J,6!7a
Bfu/9ad
private UserDAO userDAO; %!>k#F^S
s}Xi2^x
/** -%saeX Wo
* @param userDAO The userDAO to set. d4[poi ~
*/ 2f s9JP{^0
publicvoid setUserDAO(UserDAO userDAO){ r
.{rNR
this.userDAO = userDAO; u;$I{b@M]
} e1:u1(".
a"MTQFm'
/* (non-Javadoc)
Cl%V^xTb
* @see com.adt.service.UserManager#listUser "<7$2!
`>dIF.
(org.flyware.util.page.Page) p, !1 3X
*/ (Be$$W
public Result listUser(Page page)throws R
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N=hSqw[
HibernateException, ObjectNotFoundException { 3`mC"ab /
int totalRecords = userDAO.getUserCount(); ::kpl2r\c
if(totalRecords == 0) B'NS&7+].
throw new ObjectNotFoundException zUvB0\{q
i%#th'C!P
("userNotExist"); 5R$=^gE
page = PageUtil.createPage(page, totalRecords); :Fw *r|
List users = userDAO.getUserByPage(page); ,P;8 }yQ
returnnew Result(page, users); W,0KBkkp
} ~oEXM?M
Xcs8zT
} :d, >d
oiIt3<BX
-i| /JH
g-4gI\
4;B=Qoxe
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 /5Gnb.zN)
1uK)1%vK
询,接下来编写UserDAO的代码: H57jBD
3. UserDAO 和 UserDAOImpl: l6r%nHP@
java代码: d@_'P`%-
h #$_<U
M80}3mgP~
/*Created on 2005-7-15*/ _Y}^%eFw
package com.adt.dao; !NlB%cF
]W89.><%14
import java.util.List; n=lggBRx
c80"8r
import org.flyware.util.page.Page; DN2hv2
KFCQYdI`d
import net.sf.hibernate.HibernateException; bEOOFs
|DdW<IT`0
/** .&aVx]
* @author Joa UHTb61Gs
*/ ~hxeD" w
publicinterface UserDAO extends BaseDAO { C.DoXE7
2b{@]Fp
publicList getUserByName(String name)throws ylo]`Nq
roK4RYJ7)
HibernateException; MVu[gB
<v1_F;{n
publicint getUserCount()throws HibernateException; d!a2[2Us
BxW||O|_N"
publicList getUserByPage(Page page)throws =|DkD-
O
$i5G7b
HibernateException; s.k`];wo
_rWTw+
L
} (7
]\p
{Tjtj@-
*X"F: 7
?dATMmT-
NK*:w *SOI
java代码: VLl&>Pbe-
[U+<uZzOC
2/a04qA#
/*Created on 2005-7-15*/ 7~Xu71^3s
package com.adt.dao.impl; see'!CjVo2
"N=&4<]I5
import java.util.List; :6HiP&<
z^SN#v$
import org.flyware.util.page.Page; Au\=ypK
{d{WMq$
import net.sf.hibernate.HibernateException; kC,DW%Ls
import net.sf.hibernate.Query; 1{Sx V
}K qw\]`
import com.adt.dao.UserDAO; A=@V LU4%
'RN"yMv7l
/** }&'yt97+
* @author Joa |\{J`5gr
*/ {/,+_E/
public class UserDAOImpl extends BaseDAOHibernateImpl wE.@0
noD7G2o
implements UserDAO { *axza~d
=#PudF.\
/* (non-Javadoc) a*e|>p DO
* @see com.adt.dao.UserDAO#getUserByName $[L)f|
l
=r@ie>*U
(java.lang.String) 6.(]}?g1f
*/ a'L7y%
publicList getUserByName(String name)throws dnhpWVhn
f{oxF?|89
HibernateException { hyr5D9d
String querySentence = "FROM user in class _3-,3ia
~"hAb2
com.adt.po.User WHERE user.name=:name"; hPX2 Bp
Query query = getSession().createQuery ))we\I__8
5,I*F9[3
(querySentence); u]++&~i
query.setParameter("name", name); Vo58Nz:%
return query.list(); :5qqu{GL
}
e>s.mH6A
^AC+nko*
/* (non-Javadoc) NJz*N%VWD
* @see com.adt.dao.UserDAO#getUserCount() WA)lk>(+
*/ 2{Lc^6i(t
publicint getUserCount()throws HibernateException { LVz%$Cq,0
int count = 0; itvy[b-*
String querySentence = "SELECT count(*) FROM ABS
BtH ?
Mz#S5 s
user in class com.adt.po.User"; o::ymAj
Query query = getSession().createQuery z8rh*Rfxd
\ {E;u'F
(querySentence); 8Gzs
count = ((Integer)query.iterate().next
=z7Ay
n ;$}pg~
()).intValue(); pRyS8'
return count; ::h02,y;1%
} bB[*\
vU=k8
/* (non-Javadoc) 7dL=E"WL
* @see com.adt.dao.UserDAO#getUserByPage p>hCh5
:X'U`jE
(org.flyware.util.page.Page) )SO1P6
*/ V3Rnr8
publicList getUserByPage(Page page)throws -2mOgv
F$pd]F!#
HibernateException { & m ";D
String querySentence = "FROM user in class -O,O<tOm
eWt>^]H~
com.adt.po.User"; E*#60z7F
Query query = getSession().createQuery "NI>HO.U
d4rJ?qw
(querySentence); _}%#Yz
query.setFirstResult(page.getBeginIndex()) */@bNT9BgO
.setMaxResults(page.getEveryPage()); XVK[p=cIL
return query.list(); c`[uQXv
} ;Z<*.f'^fc
{b8 Y-
} QRc=-Wu_(
bJ5z??
FWx*&y~$
MjeI?k}LJ
#esu@kMU`
至此,一个完整的分页程序完成。前台的只需要调用 rzY@H }u
jMN@x]6w
userManager.listUser(page)即可得到一个Page对象和结果集对象 ^bgm0,M
ROiX=i
的综合体,而传入的参数page对象则可以由前台传入,如果用 0}3'h#33=
%QcG^R
webwork,甚至可以直接在配置文件中指定。 DT~y^h
9kiy^0
7G
下面给出一个webwork调用示例: [(ib9_`A'1
java代码: Hw-oh?=
< $/Yw
sA7K ;J})
/*Created on 2005-6-17*/ }u$aPS<$!
package com.adt.action.user; ?z36mj"`o
i /U{dzZ
import java.util.List; t
1'or
$@!&ML
import org.apache.commons.logging.Log; ?^A:~" ~
import org.apache.commons.logging.LogFactory; ,lG wW8$R
import org.flyware.util.page.Page; ?;kc%Rz
=kkA
import com.adt.bo.Result; 0BZOr-i
import com.adt.service.UserService; #~qp8
w
import com.opensymphony.xwork.Action; wEn&zZjx
ktJLpZ<0O
/** 79fyn!Iz<
* @author Joa BY2txLLB
*/ a[9OtZX<
publicclass ListUser implementsAction{ uS10P7N}
9>Z#o<*_/
privatestaticfinal Log logger = LogFactory.getLog g?Ty5~:lq
n\NDi22
(ListUser.class); xa axj
5nw9zW
:'
private UserService userService; [ESQD5&
o sH,(\4_
private Page page;
@(5RAYRV
?ew]i'9(
privateList users; N=Yi:+
}U1{&4Ph
/* WmBnc#>gK
* (non-Javadoc)
x a,LV
* KTREOOu .t
* @see com.opensymphony.xwork.Action#execute() d-2I_ )9
*/ |?Uc:VFF
publicString execute()throwsException{ B_G7F[/K
Result result = userService.listUser(page); ZuV
page = result.getPage(); \)
ONy9
users = result.getContent(); ?UZyu4O%
return SUCCESS; GM92yi!8
} #SUq.A
G#M]\)f%
/** eEFT(e5.>3
* @return Returns the page. &3/H
P)*<]
*/ f
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public Page getPage(){ *wx^mB9
return page; +Rd{ ?)2~
} 25KZe s)
t`D@bzLC%
/** XfDQx!gJ
* @return Returns the users. <]`2H}*U'
*/ ,6)y4=8 L
publicList getUsers(){ r+yLK(<zp
return users; spDRQ_qq
} !ry+ r!"
PQ|x?98
/** :G)x+0u
* @param page 4s2ex{$+MA
* The page to set. P Qay
sdb
*/ +u.L6GcB
publicvoid setPage(Page page){ f%l#g ]]
this.page = page; D1/$pA+B
} =jHy6)6w
NP/2gjp
/** 51usiOq
* @param users :S2MS{>Mo
* The users to set. L zy|<:K+$
*/ $ {"St&(
publicvoid setUsers(List users){ p0@mumh
this.users = users; <6 $%Y2
} ]<_+uciP5[
t`{Fnf
/** hidweg*7
* @param userService t0(hc7`
* The userService to set. ,5WDYk-
*/ <:o><f+
publicvoid setUserService(UserService userService){ XcneH jpR
this.userService = userService; $*ZHk0
7x
} Re>e|$.T
} }_TdXY
#w\
8h2?Q
[b'fz
KfS^sT
} 4^UVdz
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, >{8H==P
3 g&mND
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 rKq]zHgpo
mK4A/bsE
么只需要: - d6>
java代码: OkXOV
\aozecpC`
bp_@e0
<?xml version="1.0"?> C I0^eaFs
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork Czn7,KE8X
4v$AM8/o
1.0//EN" "http://www.opensymphony.com/xwork/xwork- i{0_}"B
#a:C=GV;4
1.0.dtd"> N<%,3W_-_
: Tl?yGF
<xwork> N<WFe5
L1BpY-=
<package name="user" extends="webwork- 'z:p8"h}
b.+\qaR
interceptors"> .(ir2g
ya=51~ by"
<!-- The default interceptor stack name I'hQbLlG
`$HO`d@0*R
--> %cL:*D4oz
<default-interceptor-ref TMBdneS-s
I&c#U+-A'
name="myDefaultWebStack"/> on$a]zx'@
l|{<!7a
<action name="listUser" v2Y=vr
){~.jP=-#
class="com.adt.action.user.ListUser"> 1g+<`1=KT
<param V}?5=f'
DEhA8.v
name="page.everyPage">10</param> CXA8V"@&b/
<result ~sD'pS
/jAs`"U
name="success">/user/user_list.jsp</result> T~Cd=s(T"
</action> '
r/1+.
WDq3K/7\
</package> -M}iDBJx>#
AH+J:8k
</xwork> 0Og =H79<
I6_+3}Hm{
oxZ(qfjS
~c"c9s+o
y-mmc}B>N
cA kw5}P
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 P<~y$B
ikC;N5Sw
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。 Nx__zC^r
5ZLH=8L
注:上面的<param>的配置,还需要webwork和Spring整合的配合。
'(}BfD P
(ydeZx
Rx.0P6s
nYHk~<a
J4<*KL~a
我写的一个用于分页的类,用了泛型了,hoho
Nnw iH
;N|6C+y
java代码: \=JKeL|6[S
'
BpRi N
R0WJdW#
package com.intokr.util; "d'@IN
>8Y >B)
import java.util.List; B4C`3@a
$Fj7'@1(
/** dj#<,e\
* 用于分页的类<br> o<y7Ut
* 可以用于传递查询的结果也可以用于传送查询的参数<br> '4iu0ie>D
* Jx]`!dP3
* @version 0.01 U\N`[k.F
* @author cheng bZ)Jgz
*/ ;FUd.vg{
public class Paginator<E> { n"JrjvS
privateint count = 0; // 总记录数 Kfh"XpWc$
privateint p = 1; // 页编号 6 S8#[b
privateint num = 20; // 每页的记录数 [(hENX}o:
privateList<E> results = null; // 结果 (Jm_2CN7X
E+gUzz5
/** B^
h!F8DC
* 结果总数 P06K0Fxf
*/ yI!K
quMC
publicint getCount(){ fXN;N&I
return count; Xs`/q}R
} dFlx6H+R!0
YeQX13C"Z
publicvoid setCount(int count){ &^Io\
this.count = count; H5n"!!
} ][Kj^7/
kF?\p`[a
/** UU_k"D~
* 本结果所在的页码,从1开始 lPH]fWt<
* _<8n]0lX3
* @return Returns the pageNo. \*7Tj-#
*/ `k+k&t
publicint getP(){ y(HR1vQ;Z
return p; q(C+D%xB
} ev>: 3_ s
+Fk.B@KT,
/** P)3e^~+A
* if(p<=0) p=1 BkcOsJIz
* nxG vh4'i8
* @param p plca`
*/ 4H'9y3dk
publicvoid setP(int p){ WVVqH_
if(p <= 0) +XsY*$O
p = 1; B,676~I
this.p = p; {x+jFj.
} _+GCd8d
d(tq;2-
/** /<@oUv
* 每页记录数量 ?D#Vh a
*/ ']V 2V)t
publicint getNum(){ h
/on
return num; fQ<V_loP.@
} [bAv|;
m2_B(-
/** W6Hiqu+
* if(num<1) num=1 (t <Um
Vd
*/ 8u>E(Vmpu
publicvoid setNum(int num){ nD!^0?
if(num < 1) RxqXGM`4
num = 1; %9IM|\ulp
this.num = num; :U~[%]
} {pVD`#Tl[
*w!H -*`
/** 9 eP @} C6
* 获得总页数 +s`n]1HC
*/ JI.ad_IR
publicint getPageNum(){ $Uzc
return(count - 1) / num + 1; @r#> -p
} Lm8cY
)ZT&V