Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 hsZ/Vnn`
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 \bA Yic
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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 C@rGa7
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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 bS.w<V
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分页支持类: cs9^&N:w[
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java代码: rr<E#w
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package com.javaeye.common.util; ab0Sx
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import java.util.List; C*9X;+S0J
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publicclass PaginationSupport { FhE{khc#
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publicfinalstaticint PAGESIZE = 30; %x)bZ=An
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privateint pageSize = PAGESIZE; z\YIwrq3*
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privateList items; /@os*c|je
ON ?Y
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privateint totalCount; D$>_W ,*V
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privateint[] indexes = newint[0]; c/{FDN
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privateint startIndex = 0; Fsx?(?tCMo
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public PaginationSupport(List items, int xQy,1f3s+
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totalCount){
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setPageSize(PAGESIZE); So:X!ljN(e
setTotalCount(totalCount); >}5?`.K~Q*
setItems(items); s-i|P
setStartIndex(0); xad`-vw
} yPyu)
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public PaginationSupport(List items, int Bd>~F7VWs
@Mk`Tl
totalCount, int startIndex){ [oWkd_dK
setPageSize(PAGESIZE); Bqx5N"
setTotalCount(totalCount); QYJ
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setItems(items); cHFi(K]|1
setStartIndex(startIndex); 0X$mT:=9
} 99m2aT()
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public PaginationSupport(List items, int QFh1sb)]d)
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totalCount, int pageSize, int startIndex){ _z5/&tm_H
setPageSize(pageSize); q5'S<qY^
setTotalCount(totalCount); I[Ra0Q>([k
setItems(items); T U%@_vYR
setStartIndex(startIndex); OvdT* g=8*
} &&ioGy}1
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publicList getItems(){ 6iC>CY3CG
return items; x)5}:b1B=
} dZM^?rq
4=PjS<Lu8
publicvoid setItems(List items){ A_9WSXR
this.items = items; f~IJ4T2#N
} )7q$PcY
[B0BHJ~
publicint getPageSize(){ a6p0_-MF
return pageSize; 0^;2
} K g@'mG
f%Q)_F[0D4
publicvoid setPageSize(int pageSize){ +`y(S}Z
this.pageSize = pageSize; +9)JtmoL
} ]5!3|UYS
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publicint getTotalCount(){ )0{`}7X
return totalCount; QV4|f[Ki%
} @SQsEq+A?\
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publicvoid setTotalCount(int totalCount){ b0P3S!E
if(totalCount > 0){ "gJ?LojB <
this.totalCount = totalCount; lH-VqkR\
int count = totalCount / )m%uSSx#
%1z;l. c
pageSize; MqmQ52HR
if(totalCount % pageSize > 0) b|#=kPVgL}
count++; 5'%I4@Qn+
indexes = newint[count]; K`*GZ+b|`
for(int i = 0; i < count; i++){ r924!zdbR
indexes = pageSize * %L|fTndKH
HR>Y?B{
i; p8Vqy-:
} ~o}:!y
}else{ PK\Z Rl
this.totalCount = 0; n.%QWhUB
} >KKWhJ
} q?,PFvs"
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publicint[] getIndexes(){ (f/(q-7VWt
return indexes; -YoL.`s1
} w,{h9f
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publicvoid setIndexes(int[] indexes){ &OR(]Wt0
this.indexes = indexes; ;$p !dI\-Q
} IUMv{2C
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publicint getStartIndex(){ D:P(;
return startIndex; Y2|i> 5/|<
} 9#8vPjXW}.
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publicvoid setStartIndex(int startIndex){ RQ+, 7Ir
if(totalCount <= 0) !V|{(>+<
this.startIndex = 0; ~(kEGEF
elseif(startIndex >= totalCount) osV6=
this.startIndex = indexes GT{4L]C
72HA.!ry
[indexes.length - 1]; D%SOX N
elseif(startIndex < 0) XM'tIE+|
this.startIndex = 0; w[~G^x&
else{ m^X51,+<
this.startIndex = indexes )g5?5f;
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[startIndex / pageSize]; 9>RkFV
} $b8[/],
} y6(PG:L
{!,K[QwcI
publicint getNextIndex(){ 6<&~R3dQ
int nextIndex = getStartIndex() + KsDS!O
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pageSize; hBgE%#`s
if(nextIndex >= totalCount) g 9,"u_
return getStartIndex(); F^,:p.ihm<
else $]7f1U_e
return nextIndex; Mj0,Y#=76
} ZmK=8iN9J
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publicint getPreviousIndex(){ ||+~8z#+,
int previousIndex = getStartIndex() - mhbczVw
>oh Cz@~
pageSize; 41
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if(previousIndex < 0) N8A)lYT]_u
return0; x&B&lFmo8
else }#z1>y!#
return previousIndex; ?v^NimcZ
} dx%z9[8~{.
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} *l5?_tF
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抽象业务类 ch
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java代码: SYJO3cY
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/** m*^)#
* Created on 2005-7-12 zt.kNb
*/ OqtGKda
package com.javaeye.common.business; reu[rZ&
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import java.io.Serializable; j~v`q5X
import java.util.List; @SX%q&-
j>8DaEfwx
import org.hibernate.Criteria; ;|Cdq
import org.hibernate.HibernateException; s5~k]"{j
import org.hibernate.Session; c^}G=Z1@
import org.hibernate.criterion.DetachedCriteria; .*zN@y3
import org.hibernate.criterion.Projections; ^O|fw?,
import y2W+YV*
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org.springframework.orm.hibernate3.HibernateCallback; pBtO1x6x/
import `[H^`
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org.springframework.orm.hibernate3.support.HibernateDaoS #GM^ :rF
D
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upport; AVT% AS
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import com.javaeye.common.util.PaginationSupport; U]hqRL
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public abstract class AbstractManager extends fPeS;
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HibernateDaoSupport { bBIh}aDN
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privateboolean cacheQueries = false; ^\}MG!l
W3:j Z:
privateString queryCacheRegion; aoy Be|H~=
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publicvoid setCacheQueries(boolean Av x`
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cacheQueries){ Jn+ -G4h$
this.cacheQueries = cacheQueries; ?Q:SVxzUd
} w=KfkdAJ*/
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publicvoid setQueryCacheRegion(String )KZMRAT-
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queryCacheRegion){ ]B>76?2W
this.queryCacheRegion = !MoAga_
j
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queryCacheRegion; )>@S8v,(
} ]_C"A
ns~]a:1yh
publicvoid save(finalObject entity){ ?%3dgQB'
getHibernateTemplate().save(entity); ; Z:[LJd
} YsmRY=3
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publicvoid persist(finalObject entity){ HK)m^!=
getHibernateTemplate().save(entity); 461g7R%r
} 8063LWV
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publicvoid update(finalObject entity){ JrcbJt
getHibernateTemplate().update(entity); b1Vr>:sK47
} 4,y7a=qf3
l~J d>9DwY
publicvoid delete(finalObject entity){ !Yof%%m$;
getHibernateTemplate().delete(entity); X>I3N?5
} r<!hEWO>v
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publicObject load(finalClass entity, U7WYS8
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finalSerializable id){ E#!N8fQ
return getHibernateTemplate().load B*tYp
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(entity, id); YR'F]FI
} l'I:0a
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publicObject get(finalClass entity, C0N
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finalSerializable id){ B[8bkFS>]
return getHibernateTemplate().get s{b\\$Rb
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(entity, id); ^N7H~CT"
} Pd7\Q]of
*)K\&h<{
publicList findAll(finalClass entity){ 1L,L/sOwB&
return getHibernateTemplate().find("from pU_3Z3CeE
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" + entity.getName()); !Cgj
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} _?-oPb
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publicList findByNamedQuery(finalString 5W)ST&YPL*
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namedQuery){ K]|Ud No
return getHibernateTemplate j(%N.f6
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().findByNamedQuery(namedQuery); qyM/p.mP
} J>(X0@eWz
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publicList findByNamedQuery(finalString query, xM%4/QE+
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finalObject parameter){ ??F* Z" x
return getHibernateTemplate u1meysa{0
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().findByNamedQuery(query, parameter); yzN[%/
} 1AAyzAP9`
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publicList findByNamedQuery(finalString query, OZ\6qMH3e
",,# q
finalObject[] parameters){ Mj;V.Y
return getHibernateTemplate H,} &=SCk
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().findByNamedQuery(query, parameters); uw \@~ ,d
} #gbB// <
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publicList find(finalString query){ [6a-d>e{
return getHibernateTemplate().find l!*_[r
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(query); Ef] Hpjvp
} 3en9TB
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publicList find(finalString query, finalObject :|;@FkQ
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parameter){ coAXYn
return getHibernateTemplate().find 5{'hsC
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(query, parameter); #,tT`{u1q
} _v&fIo
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public PaginationSupport findPageByCriteria ZA="Dac
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(final DetachedCriteria detachedCriteria){ 9rEBq&
return findPageByCriteria 6U{A6hH]
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); C@XS
} }xsO^K
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public PaginationSupport findPageByCriteria 6\8d6x>
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(final DetachedCriteria detachedCriteria, finalint HAn{^8"@
-+"#G?g
startIndex){ poBeEpbs
return findPageByCriteria 6nTM~]5.
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(detachedCriteria, PaginationSupport.PAGESIZE, 9w-\K]
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startIndex); [Vs\r&qL
} iaL@- dg
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public PaginationSupport findPageByCriteria i >3`V6
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(final DetachedCriteria detachedCriteria, finalint `O6#-<>
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pageSize, FW-I|kK.
finalint startIndex){ J];Sj
return(PaginationSupport) akvi^]x
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getHibernateTemplate().execute(new HibernateCallback(){
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publicObject doInHibernate IWE([<i}i[
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(Session session)throws HibernateException { `Na()r$T
Criteria criteria = ( eKgc
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detachedCriteria.getExecutableCriteria(session); +RJ{)Nec
int totalCount = 0%bCP/
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((Integer) criteria.setProjection(Projections.rowCount l>\EkUT
^BF}wQb:j
()).uniqueResult()).intValue(); [-\ Y?3
criteria.setProjection ]r;rAOWVV
wlNL;W@w
(null); dWn6-es
List items = WX4sTxJK
TOHz3=
criteria.setFirstResult(startIndex).setMaxResults %DSr@IX
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(pageSize).list(); b/_Zw^DPC
PaginationSupport ps = `Moo WG
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new PaginationSupport(items, totalCount, pageSize, m]?Z_*1
9\ "\7S/Z
startIndex); W^iK9|[qp
return ps; &%fcGNzJQ
} V,KIi_Z
}, true); <%^/uS
} QYbB\Y
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public List findAllByCriteria(final P3Ql[2
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DetachedCriteria detachedCriteria){ [ K?
return(List) getHibernateTemplate ;^/ruf[t
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().execute(new HibernateCallback(){ _&l8^MD
publicObject doInHibernate [r`KoHwdm
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(Session session)throws HibernateException { =%|`gZ
Criteria criteria = xVPSL#>
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detachedCriteria.getExecutableCriteria(session); 3#t9pI4
return criteria.list(); $$ND]qM$M
} #ksDU
}, true); 2BC!,e$Z
} 1NP
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public int getCountByCriteria(final Lc~m`=B
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DetachedCriteria detachedCriteria){ HwFg;r
Integer count = (Integer) TFkG"ev
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getHibernateTemplate().execute(new HibernateCallback(){ *z[vp2
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publicObject doInHibernate 9i\}^ s2
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(Session session)throws HibernateException { |V5BL<4
Criteria criteria = !EIH"`>!
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detachedCriteria.getExecutableCriteria(session); r $S9/
return 2xN7lfu1RB
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criteria.setProjection(Projections.rowCount g/C 7wc
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()).uniqueResult(); %uo8z~+
} !IOmJpl'
}, true); 6Y2,fW8i,
return count.intValue(); D#<y
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} L9/'zhiZBx
} %ZoJu
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}!^h2)'7
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用户在web层构造查询条件detachedCriteria,和可选的 SLuQv?R}9
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 p>)1Z<D"a
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PaginationSupport的实例ps。 (m1m}* @
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ps.getItems()得到已分页好的结果集 ++~
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ps.getIndexes()得到分页索引的数组 1tXc7NA<
ps.getTotalCount()得到总结果数 d*+}_EV)Y3
ps.getStartIndex()当前分页索引 k
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ps.getNextIndex()下一页索引 %# uw8V
ps.getPreviousIndex()上一页索引 Wqv7
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 :G#%+,
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 8TYh&n=r
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一下代码重构了。 pJg:afCg
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我把原本我的做法也提供出来供大家讨论吧: Vc'p+e|(
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首先,为了实现分页查询,我封装了一个Page类: m:Rx<E
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java代码: 7eq.UyUxs
RPa]VL1W
M}jl\{
/*Created on 2005-4-14*/ _$*-?*V&
package org.flyware.util.page; 'tTlBf7#
cV:Q(|QC
/** +PYR
* @author Joa T\wOGaCW
* x75;-q
*/ 3=]/+{B
publicclass Page { <=uO*s>%
ruqE]Hx9(
/** imply if the page has previous page */ JK)|a@BtOT
privateboolean hasPrePage; W{IP}mM
NHZMH!=4:n
/** imply if the page has next page */ crd|r."
privateboolean hasNextPage; yYOV:3!"
rREev
/** the number of every page */ ~(m6dPm$}m
privateint everyPage; M/V"Ke"N
_BG`!3U+
/** the total page number */ Q3lVx5G>4
privateint totalPage; >ptI!\i}
N
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/** the number of current page */ JBQ>"X^
privateint currentPage; 5YZ\@<|rH
@W+8z#xr'
/** the begin index of the records by the current ,,XHw;{
w;VUP@Wm
query */ m";8 nm
privateint beginIndex; "~C\Z} ;
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/** The default constructor */ Ahd{f!
public Page(){ unL1/JY z
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} FlS)m`
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/** construct the page by everyPage Rpcnpo
* @param everyPage jbOzbxR?
* */ 'H1"z!]
public Page(int everyPage){ AF{o=@
this.everyPage = everyPage; ,^xsdqpe
} uJ*|SSN~
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/** The whole constructor */ C~iFFh6:
public Page(boolean hasPrePage, boolean hasNextPage, b(ryk./ogx
Vfw +m1sS
_}Gs9sHr0K
int everyPage, int totalPage, RkdAzv!Y7
int currentPage, int beginIndex){ :Z
]E:f0P
this.hasPrePage = hasPrePage; 7Ph+Vs+h
this.hasNextPage = hasNextPage; %4To@#c
this.everyPage = everyPage; 0@f7`D
this.totalPage = totalPage; ,Ur~DXY
this.currentPage = currentPage; hYCyc-W
this.beginIndex = beginIndex; GLl@
6S>v
} ZG)C#I1;O
-JF|770i
/** \No22Je6d
* @return a7NX~9g
* Returns the beginIndex. K3UG6S\B
*/ Q!%CU8!`&
publicint getBeginIndex(){ I(WND/&
return beginIndex; ~?A,GalS
} cmh/a~vYaY
#iGz&S3iN$
/** P3XP=G`E
* @param beginIndex ( Gxv?\
* The beginIndex to set. j1toV$)P
*/ 1/qiE{NW
publicvoid setBeginIndex(int beginIndex){ [laX~(ND{
this.beginIndex = beginIndex; .yj=*N.
} 48%a${Nvvj
c9E9Rx
/** T{K+1SPy4
* @return
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* Returns the currentPage. p|%Y\!
*/ <Q-ufF85)
publicint getCurrentPage(){ zT+yZA.L
return currentPage; cfe[6N
} =Jl1D*B*
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/** TAJ 9Y<
* @param currentPage Y=rW.yK8
* The currentPage to set. Js#c9l{{
*/ -+I! (?
publicvoid setCurrentPage(int currentPage){ <F.Ol/'h
this.currentPage = currentPage; 7#|NQ=yd
} Sdt2D
&FvNz
/** lB\j>.c
* @return ?y45#Tk]
* Returns the everyPage. LveqG
*/ +Vf|YLbhJ
publicint getEveryPage(){ S(-=I!.G{
return everyPage; iii$)4V
} =yNHJHRA#
#XY]@V\
/** cwC,VYVl
* @param everyPage J2[QHr&tn
* The everyPage to set. qP<,"9!I
*/ \M532_w
publicvoid setEveryPage(int everyPage){ }w]xC
this.everyPage = everyPage; L,4^Of
} R+JI?/H
x?<5=,
/** 2RXGY
* @return |95/'a*
* Returns the hasNextPage. z=Vvb
*/ w./EJkKI
publicboolean getHasNextPage(){ Q#r 0DWo\
return hasNextPage; /eMZTh*1P
} qiF~I0_0
t@ JPnA7~
/** H62*8y8
* @param hasNextPage ft6^s(t
* The hasNextPage to set. A0X0t
*/ EhUy7b,1_
publicvoid setHasNextPage(boolean hasNextPage){ RK3/!C`
this.hasNextPage = hasNextPage; X5/{Mx`8Oz
} coFg69\^
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/** x[^A9
* @return r;T/
* Returns the hasPrePage. QF;<%QF:
*/ /[IQ:':^
publicboolean getHasPrePage(){ l{a&Zy)
return hasPrePage; \mu9ikZ<
} ,]{NZ9
EXFxiw
/** rYS D-Kq
* @param hasPrePage *f#4S_ws`
* The hasPrePage to set. "AK3t'
jF*
*/ jrl6):x
publicvoid setHasPrePage(boolean hasPrePage){ E\*",MGL
this.hasPrePage = hasPrePage; 9cmJD5OO
}
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Wkk Nyg,
/** 1;gSf.naG
* @return Returns the totalPage. 2!otVz!Mh
* ">QY'r
*/ bgK(l d`
publicint getTotalPage(){ rpT<cCem1
return totalPage; FVmg&[
.
} C|J1x4sb@
85{vz|(':
/** ~&/Gx_KU
* @param totalPage _z 5CplO
* The totalPage to set. C|zH {.H
*/ wf@2&vJ
publicvoid setTotalPage(int totalPage){ Qd4T?5 vG
this.totalPage = totalPage; &P3vcB
} LI<5;oE;
w;$+7
} qU
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VT7NWTJ,
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 "'#Hh&Us
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个PageUtil,负责对Page对象进行构造: 7&)F;;H
java代码: 6v#G'M#r
6 {Z\cwP)c
6<Wr
8u,
/*Created on 2005-4-14*/ $bosGG
package org.flyware.util.page; [alXD_
0cUt"(]
import org.apache.commons.logging.Log; ~m?~eJK#a
import org.apache.commons.logging.LogFactory; K-u/q6ufK
y21uvp'
/** Sh6Cw4 R
* @author Joa { bn#:75r
* >2
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*/ wS0bk<(
publicclass PageUtil { ?&m]du#6
U9 *2< c
privatestaticfinal Log logger = LogFactory.getLog Ohag%<1#
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(PageUtil.class); hFfaaB
!VZj!\I
/** >pvg0Fh
* Use the origin page to create a new page [9_ (+E[}
* @param page Gnt!!1_8L
* @param totalRecords uP2a\C,$
* @return odf^W
*/ ,P@-DDJ
publicstatic Page createPage(Page page, int *$C[![
np^<HfYV
totalRecords){ p'k+0=
return createPage(page.getEveryPage(), J6ShIPc
5qSZ>DZ
page.getCurrentPage(), totalRecords); "\r~,S{:
} #aX@mPm
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/** 4"x;XVNM[
* the basic page utils not including exception iBC>w+t14
QS*cd|7J;
handler X",0VO
* @param everyPage f94jMzH9z
* @param currentPage H<}eoU.
* @param totalRecords :&)/vq
* @return page O
f @#VZ
*/ {dXBXC/Ju
publicstatic Page createPage(int everyPage, int '\B"g@if
"nno)~)u
currentPage, int totalRecords){ _i@eOqoC
everyPage = getEveryPage(everyPage); B~zg"
currentPage = getCurrentPage(currentPage); .<^YE%
int beginIndex = getBeginIndex(everyPage, /'fDXSdP
{WeXURp&nF
currentPage); `lezJ(Xm
int totalPage = getTotalPage(everyPage, s[@>uP
2\B9o `Y
totalRecords); A=d$ir
K[
boolean hasNextPage = hasNextPage(currentPage, 6H,=S`V]EK
/JubiLEK
totalPage); :;;WK~*#
boolean hasPrePage = hasPrePage(currentPage); .]s(c!{y
9XqAjez\
returnnew Page(hasPrePage, hasNextPage, ZNpExfGEU
everyPage, totalPage, A{x
7
currentPage, )z235}P
{a8^6dm*E
beginIndex); ]j2v"n
} Pph8"`mv.m
zZ"U9!T
privatestaticint getEveryPage(int everyPage){ )]c3bMVE-
return everyPage == 0 ? 10 : everyPage; s[2ZxCrCw
} )QCM2
&_/%2qs
privatestaticint getCurrentPage(int currentPage){ "=\_++
return currentPage == 0 ? 1 : currentPage; 6eYf2sZ;J
} =l2Dm
_c
]3nzIr
privatestaticint getBeginIndex(int everyPage, int 66@3$P%1p
s7nX\:Bw:
currentPage){ 9me}&Fdr
return(currentPage - 1) * everyPage; 1~5q:X
} H4'DL'83
''OInfd?
privatestaticint getTotalPage(int everyPage, int -N8cjr4l
O< tnM<"(
totalRecords){ 1m<?Q&|m$
int totalPage = 0; !H|82:`t+
Ryba[Fz4Di
if(totalRecords % everyPage == 0) Hn9F
gul&
totalPage = totalRecords / everyPage; h>Uid
&:?
else vo6[2.HS
totalPage = totalRecords / everyPage + 1 ; .d~]e2x
V l~Y
return totalPage; C7 ]DJn
} F\=Rm
Ep\
privatestaticboolean hasPrePage(int currentPage){ k/_8!^:'
return currentPage == 1 ? false : true; |[owNV>
} 7XVzd]jH
e4=FU&RpNH
privatestaticboolean hasNextPage(int currentPage, >PJtG]D
{#1j"
int totalPage){ 2'<=H76
return currentPage == totalPage || totalPage == De
nt?
Awa|rIM
0 ? false : true; g7 Md
} -<51CD w,
UhSh(E8p>
71l"m^Z3zy
} MzR1<W{ O
YF! &*6m
d]7|v
r]
tSb?]J
uqa4&2(I=j
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。 UROj9COv
?H[5O+P[
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 8{G?92
{rN
'o/N}E!Pt
做法如下: X$- boe?
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 %]chL.s
m+Q5vkW
的信息,和一个结果集List: fys5-1@-p
java代码: %[Zqr;~l
XJmFJafQD
&gA6+b'
/*Created on 2005-6-13*/ 29Z!p2{hk
package com.adt.bo; T,WKoB
MjQ[^%lfL
import java.util.List; QOT)x4!)
Z#4JA/c!
import org.flyware.util.page.Page; r*6"'W>c6
;V(H7
ZM
/** ){+[$@9
* @author Joa a
IpPL8a
*/ 'T )Or,d
publicclass Result {
m%oGzx+
2#AeN6\@
private Page page; OB?S kR
kRN|TDx(
private List content; :F7k{~
NV}RRs
/** ).NcLJw_
* The default constructor W&+y(Z-t
*/ t{R5
E U
public Result(){ G Sz @rDGY
super(); 6_R\l@a
} _/,SZ-C#L4
v)@,:u)
/** oe(9mYWKa6
* The constructor using fields t1e4H=d>
* 01LZE,.
* @param page %bIsrQ~B
* @param content /~i.\^HX
*/ Gr5`1`8|
public Result(Page page, List content){ ~@T+mHny
this.page = page; GA|/7[I}
this.content = content; JsmbW|t^
} ^uyN v-'F
E tJ~dL)
/** VLcyPM@"Q!
* @return Returns the content. 0LWdJ($?
*/ F+ffl^BQ
publicList getContent(){ 81g9ZV(4
return content; Ro'jM0(KE
} Md8(`@`o
\f(Y:}9
/** r0F_;
* @return Returns the page. uu}a:qrY
*/ 1P_Fe[8
public Page getPage(){ 5ZnSA9?
return page; Y 3o^Euou
} +w "XNl
{]&R8?%
/** JAc@S20v\
* @param content .Qd}.EG
* The content to set. R{*_1cyW
*/ p{NPcT%&
public void setContent(List content){ ^DBD63N"
this.content = content; ( "_Q
} !xkj30O(G
EVR! @6@
/** 3PsxOb+
* @param page d,)}+G
* The page to set. [ZuVUOm
*/ AK6=Ydu
publicvoid setPage(Page page){ B ,V(LTE
this.page = page; +.w[6
} @. "q
} gf+o1\5t@
F?7u~b|@{
Q"A_bdg5
Ay2b,q
uu}'i\Q
2. 编写业务逻辑接口,并实现它(UserManager, 8{oZi]ob
F4Rr26M
UserManagerImpl) );=Q] >
java代码: Q}=fVY
s4(Wp3>3i
$h,d?
.u6w
/*Created on 2005-7-15*/ ZQ|5W6c
package com.adt.service; <BSSa`N`
aZ$/<|y~:_
import net.sf.hibernate.HibernateException; FIH@2zA
M3ZOk<O<R
import org.flyware.util.page.Page; 5i6VZv
(I[s3EnhS
import com.adt.bo.Result; > 84e`aGE
4bnt=5]
/** *t^eNUA
* @author Joa NN^QUB
*/ "c6<zP
publicinterface UserManager { bV_j`:MD
i&JpM]N
public Result listUser(Page page)throws +vf:z?I8
-!l^]MU
HibernateException; L${m/@9
:WVSJ,. !
} OZ=Cp$
f_rp<R>Uu
Wj&nUp{
$|k%@Q>
l_6e I
java代码: z?)He)d
/N>} 4Ay
{#N%Bq}
/*Created on 2005-7-15*/ E30Ln_^o
package com.adt.service.impl; d ,UCH
NddO*`8+)
import java.util.List; ^}J<)}Q
sZKEUSFD #
import net.sf.hibernate.HibernateException; RB[/q:
[_V:)
import org.flyware.util.page.Page; ul$,q05nb
import org.flyware.util.page.PageUtil; 6(Vhtr2(*
J smB^
import com.adt.bo.Result; ;`+`#h3-V
import com.adt.dao.UserDAO; m^Glc?g<
import com.adt.exception.ObjectNotFoundException; Ls1B\Aw _
import com.adt.service.UserManager; _B3zRO
TKo<~?
/** 1eHe~p ,
* @author Joa +Juh:1H
*/ 6|5H=*)DH
publicclass UserManagerImpl implements UserManager { `^x9(i/NE
H'Nq#K
private UserDAO userDAO; -G-3q6A
tF^g<)S;t
/** eQ;Q4
* @param userDAO The userDAO to set. gX^ PSsp
*/ %&h c"7/k
publicvoid setUserDAO(UserDAO userDAO){ J#''q"rZ
this.userDAO = userDAO; n}JPYu
} 9Sz7\W0
*}w+68eO
/* (non-Javadoc) LL.x11o3
* @see com.adt.service.UserManager#listUser pw\P<9e=
oR#Ob#&
(org.flyware.util.page.Page) tb,9a!?
*/ P\AqpQv
public Result listUser(Page page)throws t+O e)Ns
,:UX<6l
R
HibernateException, ObjectNotFoundException { q_sEw~~@!
int totalRecords = userDAO.getUserCount(); %m`zWg-
if(totalRecords == 0) GJ,aRI
throw new ObjectNotFoundException 'OD)v
h)cY])tGtK
("userNotExist"); :b@igZ<
page = PageUtil.createPage(page, totalRecords); 0q#"clw
List users = userDAO.getUserByPage(page); n1,S_Hs
returnnew Result(page, users);
JRY_nX
} Zj!Abji=O
Ys3uPs
} 35_)3R)
s6n`?,vw
APq7 f8t
@^&7$#jq%
mlB~V3M'G
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 moZm0`WR
D"^'.DL@wG
询,接下来编写UserDAO的代码: e)b%`ntF
3. UserDAO 和 UserDAOImpl: ($8t%jVWJJ
java代码: {[W(a<%bXm
]Lm'RlV
C6]OAUXy:F
/*Created on 2005-7-15*/ $gvr
-~
package com.adt.dao; ?:uNN
VD[pZ2;4
import java.util.List; "VTF}#Uo
)R &,'`\
import org.flyware.util.page.Page; DpvrMI~I_
<#*.}w~
import net.sf.hibernate.HibernateException; 3{ "O,h
Ryv_1gR!
/** d:rGyA]
* @author Joa $FX,zC<=
*/ g`[$XiR
publicinterface UserDAO extends BaseDAO { IPtvuEju\
>{nH v)
publicList getUserByName(String name)throws rt}^4IqL
?lKhzH.T
HibernateException; i\Wdo/c-H
%\6Q .V#s
publicint getUserCount()throws HibernateException; *yez:qnx
9]7u_
publicList getUserByPage(Page page)throws h/m6)m.D
+TSSi em
HibernateException; v* ~3Z1
suVmg-d
} FFvCi@oT
*x(Jq?5O7X
>2lwWXA
pj8azFZ
g7n"
java代码: ?fK1
BC7 7<R!E)
\Y5W!.(%w
/*Created on 2005-7-15*/ q-_' W,
package com.adt.dao.impl; Z
a(|(M H
3CZS)
import java.util.List; 6gU{(H
"#4dW 7E
import org.flyware.util.page.Page; k ;KdW P
r\qz5G *6
import net.sf.hibernate.HibernateException; /.Q4~Hw%}
import net.sf.hibernate.Query; eR;!(Oy=A
5/@UVY9_
import com.adt.dao.UserDAO; uQ3[Jz`y
orfp>B) 0
/** H"Dn]$Q\Z
* @author Joa PJ\0JR7a
*/ {_>em*V b
public class UserDAOImpl extends BaseDAOHibernateImpl 5o0Ch
kbI/4IRW
implements UserDAO { |"Z{I3Umg
<+tD z (
/* (non-Javadoc) Adx`8}N8
* @see com.adt.dao.UserDAO#getUserByName $/Ov2z
VW<0Lt3
(java.lang.String) (.23rVvnT@
*/ j.|U=)E
publicList getUserByName(String name)throws ,D=fFpn
caq} &A]C
HibernateException { tef^ShF]
String querySentence = "FROM user in class
QG3&p<
!mnUdR|>(
com.adt.po.User WHERE user.name=:name"; D1T@R)j
Query query = getSession().createQuery 'EhBRU%
L%h/OD
(querySentence); >I'%!E;
query.setParameter("name", name); i.y)mcB4
return query.list(); .*5 Z"Q['G
} >)**khuP7
ELD!{bMT
/* (non-Javadoc) JAjku6
* @see com.adt.dao.UserDAO#getUserCount() \ |!\V
*/ K$[$4 dX]
publicint getUserCount()throws HibernateException { U[\Vj_?(I
int count = 0; z5 m>H;P
String querySentence = "SELECT count(*) FROM 2A:,;~UH
wCKj7y[
user in class com.adt.po.User"; {/8Q)2*>0
Query query = getSession().createQuery {eT.SO
I 3$dVls}
(querySentence); TO#Pz.)>B6
count = ((Integer)query.iterate().next .~D>5 JnEk
!8Rw O%c(
()).intValue(); tWPO]3hW
return count; {D`T0qPT[
} osP\DiQ
$l[Rh1z`;+
/* (non-Javadoc) ftbpqp'
* @see com.adt.dao.UserDAO#getUserByPage 01@t~v3!Z
md Gwh7/3
(org.flyware.util.page.Page) zsQoU&D 5
*/ l*=aMjd?
publicList getUserByPage(Page page)throws EqB)sK/3
N{Qxq>6 G
HibernateException { L>9R4:g
String querySentence = "FROM user in class ip:LcG t
;;U:Jtn2
com.adt.po.User"; 9Kv|>#zff
Query query = getSession().createQuery b[ w;i]2
5Av=3[kh"%
(querySentence); E-2eOT
query.setFirstResult(page.getBeginIndex()) Y]g?2N=E
.setMaxResults(page.getEveryPage()); G4-z3e,crr
return query.list(); ,xi({{L*
} AC- )BM';
]0j9>s2|Z
} Z;DCI-Wg
dJk9@u
,!QV>=
;0%OB*lcgE
iThSt72
至此,一个完整的分页程序完成。前台的只需要调用 83Ou9E!W
zGo|JF
userManager.listUser(page)即可得到一个Page对象和结果集对象 K\?]$dK5
DBH#)4do@
的综合体,而传入的参数page对象则可以由前台传入,如果用 {dWObh
r6.d s^
webwork,甚至可以直接在配置文件中指定。 ~/#1G.H
mTDVlw0dh
下面给出一个webwork调用示例: &, a3@i
java代码: Fke//- R
o>]`ac0b}Y
dY!Z
/*Created on 2005-6-17*/ bn9;7`>.
package com.adt.action.user; zw@'vncc
o^p
import java.util.List; M[]A2'fS
5"KlRuv%
import org.apache.commons.logging.Log; 2umv|]n+l|
import org.apache.commons.logging.LogFactory; #1nJ(-D+
import org.flyware.util.page.Page; 6p;m\
}j{!-&
import com.adt.bo.Result; pox,Im
import com.adt.service.UserService; R{hf9R ,
import com.opensymphony.xwork.Action; I/J7rkf
sy5 Fn~\R
/** ?}P5p^6
* @author Joa ^"8wUsP
*/ Hf gz02Z$
publicclass ListUser implementsAction{ b7:0#l$
s][24)99
privatestaticfinal Log logger = LogFactory.getLog [U{UW4
&:#h$`4
(ListUser.class); =6nD sibf
5jcte<
5I_
private UserService userService; $7Jo8^RE
}:Z9Vc ZP`
private Page page; N_C;&hJN$w
9)dfL?x8V{
privateList users; $%k1fa C
$4=f+ "z
/* RVw9Y*]b
* (non-Javadoc) clO,}Ph>
* k+ o|0
* @see com.opensymphony.xwork.Action#execute() 7 A$B{
*/ vb{i
publicString execute()throwsException{ r#i?j}F}
Result result = userService.listUser(page); \_6OC Vil
page = result.getPage(); ,El!fgL
users = result.getContent(); 2\D8.nQr
return SUCCESS; ;t#]2<d*
} LJlZ^kh
aBuoHdg;
/** V&{MQWy
* @return Returns the page. S_(d9GK<
*/ KFRw67^
public Page getPage(){ (]2H7X:b
return page; PXKJ^fa
} <cN~jv-w$
m:QG}{<.h
/** &]6)LFm
* @return Returns the users. {}~: &.D
*/ YvL?j
publicList getUsers(){ Y$>-%KcKeI
return users; bzpFbfb
} m!n/U-^
W~n.Xeu{C
/** >`RRP}u=u
* @param page Ut@RGg+f8
* The page to set. >H][.@LyR
*/ \*T"M*;
publicvoid setPage(Page page){ OR6ML-|
this.page = page; jyS=!ydn+
} fK}h"iH+K
6]cryf&b
/** KxGX\
* @param users \ gwXH
* The users to set. J97R0
*/ koG{
|elgB
publicvoid setUsers(List users){ ]$-cMX
this.users = users; 8TV;Rtl
} ed 59B)?l
Q[n\R@
/** 3Mjj'5KH!
* @param userService ~`8hwR1&z
* The userService to set. SUCUP<G
*/ 9Ru;`
publicvoid setUserService(UserService userService){ uLeRZSC
this.userService = userService; 5v.DX`"
} sfT+i;p
} , :n|
?7
yY{kG2b,
+>^7vq-\'
]w).8=I
<z+:j!~
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,
%V G/
BcWcdr+}9
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 `bI)<B
`1` f*d
v
么只需要: <Cpp?DW_
java代码: YB))S!;Ok
^WYQ]@rh3
QWnndI_4p
<?xml version="1.0"?> fN%jJ-[d
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork >u+q1j.
ZM#=`k9
1.0//EN" "http://www.opensymphony.com/xwork/xwork- }l0&a!C
\BV
0zKd
1.0.dtd"> U
5w:"x
z$lF)r:Bc
<xwork> w?vVVA
5MTgK=c
<package name="user" extends="webwork- Lm*VN~2
.
v)mZp
interceptors"> &[R8Q|1j
8^^[XbH
<!-- The default interceptor stack name .9G<y 4
XE3aXK'R
--> {QaNAR=)
<default-interceptor-ref P,pnga3Wu
H!IshZfktn
name="myDefaultWebStack"/> 4DWwbO
[dX`K`k
<action name="listUser" z2c5m
M(q'%XL^
class="com.adt.action.user.ListUser"> e&q?}Ho
<param l]!9$
'(+<UpG_Q}
name="page.everyPage">10</param> Tpp &
<result /?-7Fg+,
6R UrF
name="success">/user/user_list.jsp</result> 0[A9b,MMVO
</action> (P|~>k
5r{;CKKz
</package> "VxWj}+]
,{eUP0]
</xwork> h&@R| N
4 {GU6v)f
4\5uY
QrG`&QN
V,v[y\
f7de'^t9
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 (n{wg(R
pI[ZBoR~
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。 ,3DXFV'uxb
Fig&&b a
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 `D5HC
;,'igdold
oS,I~}\kQ
NVV}6TUV
AN:@fZ
我写的一个用于分页的类,用了泛型了,hoho Pi2|
" K*
java代码: SF]@|
1M3%fW
rEZ8eeB[3
package com.intokr.util; m#H3:-h,
Ei>m0
~<\
import java.util.List; C_:k8?
n}-3o]ku
/** Ok-.}q>\Mv
* 用于分页的类<br> ;(6g\'m
* 可以用于传递查询的结果也可以用于传送查询的参数<br> Rs& @4_D
* xgsjm))
* @version 0.01 "$HbK
@]!h
* @author cheng [f~N_G6I^o
*/ o/cjXun*
public class Paginator<E> { ^,Ydr~|T
privateint count = 0; // 总记录数 <oMUQ*OtV
privateint p = 1; // 页编号 }1 vT)
privateint num = 20; // 每页的记录数 _1Z=q.sC
privateList<E> results = null; // 结果 lt'I,Xt
Eu<1Bse;
/** Mq%,lJA\
* 结果总数 7YWNd^FI
V
*/ HHk)ZfWRo
publicint getCount(){
Y]aW)u
return count; `:{B(+6
} p^m5`{1]x
0Sl]!PZR1
publicvoid setCount(int count){ 72T I
this.count = count; eHg3}b2r
} "](6lB1Oe
7XrfuG*L$
/** cvsz%:Vs
* 本结果所在的页码,从1开始 z+2V4s =
* wgeNs9L
* @return Returns the pageNo. pj|pcv^
*/ Q'B6^%:<~
publicint getP(){ ?@6b>='!
return p; q(^Q3
} ]Z<_ "F
c/W=$3
/** RWq{Ff}Hk
* if(p<=0) p=1 /G{_7cb
* Jwn AW}=
* @param p f6<g3Q7Mu
*/ U4?(A@z9^
publicvoid setP(int p){ m@Ev~~;
if(p <= 0) /Wk9-uH
p = 1; )w~Fo,
this.p = p; }71LLzG`/
} /Poet%XvRx
(3vHY`9
/** I XA>`D
* 每页记录数量 (n(
fI f
*/ z;u>
Yz+3
publicint getNum(){ )(Iy<Y?#
return num; Tm]nEl)_
} ,0$)yZ3*3,
R/b4NGW@
/** J a,d3K
* if(num<1) num=1 r~[vaQQ6L
*/ m,LG=s
publicvoid setNum(int num){ lEL78l.
if(num < 1) 01a-{&
num = 1; u8b2$D
this.num = num; JEn3`B!*
} 1nj(hg
`<\}FS`'
/** <T?oKOD ]
* 获得总页数 OqhD7 +
*/ 6V9doP ]i
publicint getPageNum(){ &`|:L(+
return(count - 1) / num + 1; n
?[/ufl
} Zzua17
&6 -k#r
/** X##1!
ad
* 获得本页的开始编号,为 (p-1)*num+1 !SOrCMHx
*/ eZhPu'id\s
publicint getStart(){ dP$GThGl
return(p - 1) * num + 1; M
s9E@E
} qgt[ ~i*
3{Nbp
/** %rQuBi# 1f
* @return Returns the results. `\>.h
*/ +y+"Fyl
publicList<E> getResults(){ xk~IN%\
return results; &tR(n$M@>
} W3W'oo
}`VDD?M
public void setResults(List<E> results){ <c[U#KrvJ
this.results = results; E&$_`m;
} v'2[[u{7*
4\t1mocCSN
public String toString(){ W~T}@T:EN
StringBuilder buff = new StringBuilder #PvB/3
Q3W#`6jpF
(); $V>98M>j
buff.append("{");
,"-Rf<q/
buff.append("count:").append(count); n]W_e
buff.append(",p:").append(p); K?x,T8<aW
buff.append(",nump:").append(num); SM 0M%
buff.append(",results:").append 5`/@N{e
.@ C{3$,VG
(results); Rn%N&1
Ef
buff.append("}"); Ko>&)%))$X
return buff.toString(); f67NWFX
} }0hL~i
R$kpiqK
} =tTqN+4
2],_^XBvB
@*N)i?>