Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 4}r\E,`*X
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 (to/9OrG
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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 u75)>^:I
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 pdcwq~4~%
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。 \KnD"0KW
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分页支持类: 'WM~
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java代码: "M5ro$qZ}
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package com.javaeye.common.util; o?Tp=Ge
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import java.util.List; _/z)&0DO
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publicclass PaginationSupport { upEPv
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publicfinalstaticint PAGESIZE = 30; WV!kA_
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privateint pageSize = PAGESIZE; &=6cz$]z
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privateList items; n|4D#Bd1w
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privateint totalCount; # 1qVFU
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privateint[] indexes = newint[0]; n[MIa]dK
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privateint startIndex = 0; eB/hyC1
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public PaginationSupport(List items, int #iqhm,u7D
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totalCount){ ad3z]dUZ9
setPageSize(PAGESIZE); }JpslY*aS
setTotalCount(totalCount); h2/1S{/n]
setItems(items); yZ(Nv $[5
setStartIndex(0); yK>0[6l
} i6g[E4nk
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public PaginationSupport(List items, int ncw?;
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totalCount, int startIndex){ .5[LQR
setPageSize(PAGESIZE); 5(MZ%-~l
setTotalCount(totalCount); {GH`V}Ob
setItems(items); 7L~ zI>2
setStartIndex(startIndex); h7W%}6Cqkw
} i37a}.;
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public PaginationSupport(List items, int VqO<+~M,E
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totalCount, int pageSize, int startIndex){ +VpE-X=T
setPageSize(pageSize); )r6SGlE[Y
setTotalCount(totalCount); {, *Y
setItems(items); p`l[cVQ<
setStartIndex(startIndex);
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} D'sboOY
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publicList getItems(){ B 1ZHV^
return items; 5 dNf$a0E
} tm36Lw
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publicvoid setItems(List items){ s*~jvL
this.items = items; w<F;&';@h
} )zLS,/pk^
f w>Gx9
publicint getPageSize(){ + x;ML
return pageSize; 5N3!!FFE
} 8|-mzb&
fe9& V2Uu
publicvoid setPageSize(int pageSize){ luz%FY:
this.pageSize = pageSize; Qpv}N*v^
} f$S
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publicint getTotalCount(){ W.6JnYLQ&
return totalCount; 2p;}wYt
} n.qxxzEN
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publicvoid setTotalCount(int totalCount){ /%q9hI
if(totalCount > 0){ +D-+}&oW
this.totalCount = totalCount; \F+o=
int count = totalCount / g
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pageSize; (7jB_ p%
if(totalCount % pageSize > 0) n\ ',F
count++; io33+/
indexes = newint[count]; acju!,G
for(int i = 0; i < count; i++){ r5qx! >
indexes = pageSize * c'Tu,-
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i; SnF[mN'
} _Il9s#NA%
}else{ 6 r-n6#=
this.totalCount = 0; 3w:Z4]J
} jUR#
} |e[0Qo@
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publicint[] getIndexes(){
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return indexes; _}9R}
} dVGUhXN6
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publicvoid setIndexes(int[] indexes){ GxDF7
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this.indexes = indexes; oY6|h3T=Q$
} NUnc"@
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publicint getStartIndex(){ <VxpMF
return startIndex; MJ/%$
} #|_UA}Y
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publicvoid setStartIndex(int startIndex){ '>mb@m
if(totalCount <= 0) ].f,3itg&
this.startIndex = 0; ;pyJ O_R[
elseif(startIndex >= totalCount) f]A6Mx6
this.startIndex = indexes ST8/
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[indexes.length - 1]; #bZ=R
elseif(startIndex < 0) q.b4m 'J
this.startIndex = 0; PXu<4VF
else{ g!Yh=kA'N
this.startIndex = indexes MH8%-UV
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[startIndex / pageSize]; 6F&]Mk]V8
} K2MNaB
} iEgM~
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publicint getNextIndex(){ W#\};P
int nextIndex = getStartIndex() + Z#:@M[HH{
m'"VuH?^
pageSize; }=m?gF%3
if(nextIndex >= totalCount) "/Q(UV<d
return getStartIndex(); xA'#JN<*
else 7Z~szD
return nextIndex; $,zM99
} ;xtb2c8HT
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publicint getPreviousIndex(){ 3v>,c>b([
int previousIndex = getStartIndex() - _7"W\gn:9
gH//
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pageSize; skx=w<YO6]
if(previousIndex < 0) 1nTaKK
q
return0; p}|wO&4h
else vfTG*jG
return previousIndex; G/3lX^Z>
} =}GyI_br;8
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} {ZEXlNPww
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抽象业务类 I%C:d#p
java代码: Bo\v-97
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/** F8;4Oj
* Created on 2005-7-12 EjE`S_i=
*/ XTaWd0Y
package com.javaeye.common.business; Or)c*.|\
j?hyN@ns
import java.io.Serializable; pz}hh^]t
import java.util.List; tUF]f6
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import org.hibernate.Criteria; &:f'{>3z
import org.hibernate.HibernateException; FH(+7Lz4;
import org.hibernate.Session; 9+Bq00-Z$
import org.hibernate.criterion.DetachedCriteria; Prx s2 i 8
import org.hibernate.criterion.Projections; kR?n%`&k
import 7tKft
sZBO_](S
org.springframework.orm.hibernate3.HibernateCallback; L(P:n-^
import 3v+}YT{>b
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org.springframework.orm.hibernate3.support.HibernateDaoS <U`Nb) &
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upport; vm}.gQ
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import com.javaeye.common.util.PaginationSupport; -"9)c^KVx
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public abstract class AbstractManager extends Xtnmh)'K~#
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HibernateDaoSupport { f|1FqL+T]
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privateboolean cacheQueries = false; r74w[6(
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privateString queryCacheRegion; >M85xjXP
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publicvoid setCacheQueries(boolean *`'%tp"'+
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cacheQueries){ IVODR
this.cacheQueries = cacheQueries; Cs=i9.-A
} Qh%vh;|^
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publicvoid setQueryCacheRegion(String Jn&>Z? @
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queryCacheRegion){ Yx c >+mx
this.queryCacheRegion = 3-%~{(T/
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queryCacheRegion; @5GP;3T
} t1s@Ub5);I
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publicvoid save(finalObject entity){ 8@
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getHibernateTemplate().save(entity); g]JI}O*5
} 4<Y[L'UaA@
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publicvoid persist(finalObject entity){ #wuE30d
getHibernateTemplate().save(entity); g~u!,Zc
} *X5LyO3-gP
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publicvoid update(finalObject entity){ iqP0=(^m
getHibernateTemplate().update(entity); i.,B
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} uW_ /7ex
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publicvoid delete(finalObject entity){ IQY#EyTb
getHibernateTemplate().delete(entity); vu >@_hv
} vA~hkkj{
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publicObject load(finalClass entity, A1T;9`E
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finalSerializable id){ .sMi"gg
return getHibernateTemplate().load ~h|L;E"
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(entity, id); 1&E&8In]$r
} P"<ad
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publicObject get(finalClass entity, ~,1X>N"
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finalSerializable id){ RlIqH;n
return getHibernateTemplate().get oC>~r1.j
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(entity, id); * OFT)S
} m':m`,c!
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publicList findAll(finalClass entity){ ueo3i1
return getHibernateTemplate().find("from "+Rm4_
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" + entity.getName()); &_gmQ;%t:
} l%/,Ef*3
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publicList findByNamedQuery(finalString Ut@)<N
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namedQuery){ v9kzMxs,
return getHibernateTemplate 6Z:|"AwC2
M!@[lJ
().findByNamedQuery(namedQuery); |REU7?B
} 3E:<
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publicList findByNamedQuery(finalString query, vUA`V\
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finalObject parameter){ xSZw,
return getHibernateTemplate tF(mD=[
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().findByNamedQuery(query, parameter); a)b@en;v
} T3 Fh7S /
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publicList findByNamedQuery(finalString query, |3@]5f&
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finalObject[] parameters){ ]ORat.*0[T
return getHibernateTemplate $R4\jIewV
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().findByNamedQuery(query, parameters); 4f5$^uN$qA
} #{sb>^BF
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publicList find(finalString query){ \02e
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return getHibernateTemplate().find euK!JZ
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(query); ['j,S<Bu~
} oQO3:2a
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publicList find(finalString query, finalObject ,B><la87
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parameter){ iqYc&}k,
return getHibernateTemplate().find 54&2SU$kx
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(query, parameter); hG]20n2
} E}+A)7mA
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public PaginationSupport findPageByCriteria FT6cOMu
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(final DetachedCriteria detachedCriteria){ }_x oT9HUr
return findPageByCriteria 8%B @[YDe
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); __ [q`
} J4; ".Y=
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public PaginationSupport findPageByCriteria !j@ 8:j0WY
q\<vCKI-^
(final DetachedCriteria detachedCriteria, finalint oY: "nE
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startIndex){ g(Nf.hko
return findPageByCriteria 6(=:j"w0
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(detachedCriteria, PaginationSupport.PAGESIZE, 8wd2\J,]
gS ]'^Sr
startIndex); ),eiJblH
} $?YkgK
oR }
public PaginationSupport findPageByCriteria + h&V;
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(final DetachedCriteria detachedCriteria, finalint z?^p(UH
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pageSize, K||85l?<
finalint startIndex){ _ev^5`>p/
return(PaginationSupport) "%Ak[04'
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getHibernateTemplate().execute(new HibernateCallback(){ 1C{~!=6#
publicObject doInHibernate ~+Y;jAdU
$- L)>"
(Session session)throws HibernateException { RVe3@|9(G
Criteria criteria =
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detachedCriteria.getExecutableCriteria(session); 5+r#]^eQY-
int totalCount = CT : ac64
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((Integer) criteria.setProjection(Projections.rowCount -e ya$C
8V nZ@*
()).uniqueResult()).intValue(); UJI1n?~
criteria.setProjection 5`J.
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(null); @`yfft
List items = jZGmTtx
9}-,dgAB
criteria.setFirstResult(startIndex).setMaxResults 8b/yT4f
(|-/S0AV
(pageSize).list(); aSj$62G"
PaginationSupport ps = xab[
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new PaginationSupport(items, totalCount, pageSize, 03xQ%"TU<
x]:mc%4-Z
startIndex); 4_ 3\4
return ps; G2rvi=8=
} = FQH
}, true); PHoW|K_e
} $8Zw<aEJ
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public List findAllByCriteria(final !O\r[c
'*pq@|q;t
DetachedCriteria detachedCriteria){ {`: !=
return(List) getHibernateTemplate `` ={FaV~m
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().execute(new HibernateCallback(){ ~I'hiV^-
publicObject doInHibernate @`3)?J[w
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(Session session)throws HibernateException { h1"#DnK7
Criteria criteria = 'ySWf,Q^
6Z3v]X
detachedCriteria.getExecutableCriteria(session); e&:fzO<~I
return criteria.list(); +XQ6KG&
} #f[yp=uI:
}, true); X'5te0v`3
} yF*JzE 7,
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public int getCountByCriteria(final -V\33cA
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DetachedCriteria detachedCriteria){ c;Li~FLR
Integer count = (Integer) 5d)G30
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getHibernateTemplate().execute(new HibernateCallback(){ K3jno+U&
publicObject doInHibernate u5lj+?
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(Session session)throws HibernateException { Qr/?tMALc
Criteria criteria = `VHm,g2
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detachedCriteria.getExecutableCriteria(session); DQ,Q yV
return Y$N|p{Z
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criteria.setProjection(Projections.rowCount 6ik6JL$AI
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()).uniqueResult(); &Z9b&P
} iVFnt!
}, true); E*kS{2NAq
return count.intValue(); re<"%D
} @sVBG']p
} -V9Cx_]y
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用户在web层构造查询条件detachedCriteria,和可选的 i22R3&C
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 0-=QQOART\
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PaginationSupport的实例ps。 Tux~4W
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ps.getItems()得到已分页好的结果集 !OiP<8 ,H
ps.getIndexes()得到分页索引的数组 1[!Idl ?m
ps.getTotalCount()得到总结果数 HzWZQ6o
ps.getStartIndex()当前分页索引 \PL92HV
ps.getNextIndex()下一页索引 0ya_[\
ps.getPreviousIndex()上一页索引 2-8<uU y
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 4pF%G
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 0evG
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一下代码重构了。 'A4Lr
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我把原本我的做法也提供出来供大家讨论吧: ?L|@{RS{|
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首先,为了实现分页查询,我封装了一个Page类: 2f4 *r^
java代码: >b/Yg:t
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/*Created on 2005-4-14*/ 55hJRm3
package org.flyware.util.page; [j&>dE
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/** Dtn|$g,
* @author Joa +&JF|#FQ`
* puDy&T
*/ rGx1>xd(k
publicclass Page { (R.k.,z
sjztT<{Q^-
/** imply if the page has previous page */ t@b';Cuv
privateboolean hasPrePage; #*?a"
~B/|#o2
/** imply if the page has next page */ )5bhyzSZI
privateboolean hasNextPage; R\6#J0&Y-
.0Cpqn,[
/** the number of every page */ 16xM?P
privateint everyPage; pp/Cn4"w
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/** the total page number */ ytHa[U
privateint totalPage; az7L0pp
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/** the number of current page */ `$Q
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privateint currentPage; 24]O0K
g(|p/%H
/** the begin index of the records by the current GT`:3L
:;rd!)5
query */ u2o6EU`
privateint beginIndex; :*Sl\:_X)
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/** The default constructor */ E}yl@8g:#
public Page(){ 5q@o,d
ix,5-j
} :QB Wy
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/** construct the page by everyPage KK/~W
* @param everyPage _epi[zf@
* */ -SZ^;t
public Page(int everyPage){ ^?w6
this.everyPage = everyPage; F~z4T/TN%G
} 9^>nZ6
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/** The whole constructor */ BIS5u4
public Page(boolean hasPrePage, boolean hasNextPage, ga0W;Vq&X
kx*=1AfU+Y
vxY7/ _]
int everyPage, int totalPage, [Nsv]Yz
int currentPage, int beginIndex){ HP"5*C5D
this.hasPrePage = hasPrePage; *b~$|H-\
this.hasNextPage = hasNextPage; DCFYpkR%
this.everyPage = everyPage; J!~?}Fq/z
this.totalPage = totalPage; OlQ7Yi>
this.currentPage = currentPage; %E,s*=j
this.beginIndex = beginIndex; @/yef3
} [iB`- dE,
67%o83\
/** ^DM^HSm
* @return #|xK>;
* Returns the beginIndex. l '<gkwX
*/ @'jC>BS8`
publicint getBeginIndex(){ Em %"]B
return beginIndex; ;y
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} ){ArZjG>
[$
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/** FlgK:=Fmj
* @param beginIndex
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* The beginIndex to set. I~gU3(
*/ 7J.alV4`/
publicvoid setBeginIndex(int beginIndex){ vSX71
this.beginIndex = beginIndex; TlQu+w|
} Si.3Je[q
d>VerZZU
/** ,FlF.pt
* @return /2tgxm$}
* Returns the currentPage. ;gP@d`s
*/ XN'x`%!*3#
publicint getCurrentPage(){ 9YwK1[G6/
return currentPage; s:~3|D][
} #0zMPh /U}
ej4xW~_
/** 3T+#d-\
* @param currentPage L?23Av0W
* The currentPage to set. LSs!U
3"
*/ 8%@7G*
publicvoid setCurrentPage(int currentPage){ ZEiW\ V
this.currentPage = currentPage; S8TJnv`?'
} !:'%'@uc
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/** G n>#Mvq
* @return =TE6R 0b
* Returns the everyPage. 6p=AzojoB
*/ p;,Cvw{.;%
publicint getEveryPage(){ Zx@/5!_n.
return everyPage; k}(C.`.
} 6av]LY K
:}i
#ODJ
/** E%FCOKw_
* @param everyPage 8*k#T\
* The everyPage to set. H<92tP4M
*/ *VmJydd
publicvoid setEveryPage(int everyPage){ 2WE_NEpJI
this.everyPage = everyPage; \=P+]9
} ]k-<[Z;I,
1Y'9|+y+
/** *F42GiBZR
* @return URz$hcI8
* Returns the hasNextPage. Y&6vTU
*/ N<}{oIsZ+
publicboolean getHasNextPage(){ Y_ b;1RN
return hasNextPage; Bb_R~1
l
} !vH7vq
[7]Kvb2t
/** 5ztHar~f
* @param hasNextPage 6p|*H?|It
* The hasNextPage to set. T:p,!?kc7
*/ :FcYjw
publicvoid setHasNextPage(boolean hasNextPage){ |]kcgLqj
this.hasNextPage = hasNextPage; y9kydu# q
} ?nZQTO7
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/** i"V2=jTeBv
* @return @F%H 1
* Returns the hasPrePage. ]A+q:kP
*/ f?}~$agc
publicboolean getHasPrePage(){ o&g-0!"
return hasPrePage; ~"6/OJA
} \D}K{P
)FVW/{NF@q
/** U{6i5;F#H
* @param hasPrePage aZ"9)RJe
* The hasPrePage to set. 1iyd{r7|
*/ F0
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publicvoid setHasPrePage(boolean hasPrePage){ d}#G~O+y3v
this.hasPrePage = hasPrePage; @62QDlt;
} HIM>%
Wyh
/** a7KP_[_(
* @return Returns the totalPage. qw={gZ
* P4@<`Eb
*/ hYOUuC
publicint getTotalPage(){ 8#b>4Dx
return totalPage; 5:ca6H
} t
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Hry*.s -
/** )xwWig.
* @param totalPage HMDQEd;
* The totalPage to set. vF,\{sgW
*/ B]jN~CO?
publicvoid setTotalPage(int totalPage){ J}a 8N.S
this.totalPage = totalPage; 46^LPC"x
} DWT4D)C,U
OJ0Dw*K<
} 2O}UVp>
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2@ 4^ 81
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 sY,q*}SLD
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个PageUtil,负责对Page对象进行构造:
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java代码: (NPDgR/
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/*Created on 2005-4-14*/ lB_&Lq8G
package org.flyware.util.page; l'h[wwEXm{
NgH"jg-
import org.apache.commons.logging.Log; *p)1c_
import org.apache.commons.logging.LogFactory; p<%76H
A
<~ E'% 60;
/** =<~/U?
* @author Joa `}uOlC]I
* 3e~X`K1Q<
*/ 96M?tTa
publicclass PageUtil { e]N?{s
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privatestaticfinal Log logger = LogFactory.getLog 'Y`.0T[&
}ti+tM*
(PageUtil.class); Z[+H$ =$%
eyPh^c]?`8
/** ~]t/|xep
* Use the origin page to create a new page ODE9@]a
* @param page eLC}h %
* @param totalRecords NY]`1yy
* @return
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*/ eq>E<X#<
publicstatic Page createPage(Page page, int r[2N;U
GWP;;x%
totalRecords){ X2ShxD|
return createPage(page.getEveryPage(), 7|=*z
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page.getCurrentPage(), totalRecords); i^hgs`hvU
} eO<:X|9T
Ya$JX(aUe
/** ;Kb]v\C:
* the basic page utils not including exception l+$e|F
WR;"^<i9
handler LeY!A#j
* @param everyPage zD8q(]: A
* @param currentPage %DJxUuh
* @param totalRecords \ dpsyc
* @return page @r.u8e)l
*/ ,]ALyWGuX
publicstatic Page createPage(int everyPage, int h9Zf4@w
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currentPage, int totalRecords){ G4Y]fzC
everyPage = getEveryPage(everyPage); b.jxkx\nt
currentPage = getCurrentPage(currentPage); WgBV,{C
int beginIndex = getBeginIndex(everyPage, "+^d.13+]
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currentPage); dL9QYIfP
int totalPage = getTotalPage(everyPage, hGc')
{.
r/tV5IH
totalRecords); N?j,'gy4
boolean hasNextPage = hasNextPage(currentPage, tmAc=?|Wa
q#W7.8 Z@
totalPage); cB5|%@$I
boolean hasPrePage = hasPrePage(currentPage); q*Xp"yBTo
u#tLY/KA
returnnew Page(hasPrePage, hasNextPage, -#XNZy!//
everyPage, totalPage, imE5$;
currentPage, lH_S*FDa
,$ICv+7]
beginIndex); "WKE%f
} J?Kgev%
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privatestaticint getEveryPage(int everyPage){ n1Ag o3NM
return everyPage == 0 ? 10 : everyPage; 7QdU|1]
} v5i?4?-Z
P<iS7Ys+
privatestaticint getCurrentPage(int currentPage){ ^:0NKq\
return currentPage == 0 ? 1 : currentPage; x+h7OvW{
} H^s@qh)L
>j]*=&,7
privatestaticint getBeginIndex(int everyPage, int |qra.\
IyE9G:fY
currentPage){ $;<h<#_n;
return(currentPage - 1) * everyPage; ; *G[3kk
} TI-#\v9
-B\`O*Q
privatestaticint getTotalPage(int everyPage, int 2fc8w3
22?9KZ`Z=
totalRecords){ #+Lo&%p#3
int totalPage = 0; h#bpog
A/NwM1z[o)
if(totalRecords % everyPage == 0) "yMr\jt~-
totalPage = totalRecords / everyPage; 6"Tr$E
else 64s9Dy@%F
totalPage = totalRecords / everyPage + 1 ; ~g2ColFhu
7{oG4X!
return totalPage; |L{<=NNs:D
} GXaCH))TO
B^(0>Da\
privatestaticboolean hasPrePage(int currentPage){ D]+tr%
return currentPage == 1 ? false : true; l'N>9~f
} UQz8":#V
wL 5p0Xl
privatestaticboolean hasNextPage(int currentPage, qIQvix$8
_\ n'uW$
int totalPage){ ,cm;A'4]
return currentPage == totalPage || totalPage == DBi3 j
:xd&V%u`
0 ? false : true; F]Zg9c{#
} h+$1+Es
g5TXs^g
kKVq,41'
} XQ:HH 8
ZMJ\C|S:
1 'EMYQ
Z2B59,I
LV=!nF0
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。 d87pQ3e:&
^r=#HQGt
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 /IVw}:G
fw^mjD
做法如下: FK!9to>
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 g#=^U`y
R{.wAH(
的信息,和一个结果集List: Ki-CJy
java代码: 57+^T}/>
?,|_<'$4T
6X5m1+ Oi^
/*Created on 2005-6-13*/ r2QC$V:0
package com.adt.bo; <u44YvLBm
C78d29
import java.util.List; ^sH1YE}0
=1n>vUW+J
import org.flyware.util.page.Page; (J Fa
V]}/e!XK\
/** t]FFGnBZ
* @author Joa I_xJ[ALdm
*/ w`1qx;/!
publicclass Result { BU:s&+LYUv
-tx)7KV-
private Page page; qd3B>f
2!dIW5I
private List content; UR-e'Z&]
u
` 9Eh;
/** Uy ;oJY
* The default constructor I}Q3B3Byg
*/ Fg4eIE-/M
public Result(){ wr*A%:
super(); /H^bDUC :r
} (m3p28Q?
[sz#*IJ
/** ..;LU:F
* The constructor using fields (B]Vw+/
* l%B1JGu*F
* @param page %8
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* @param content _a*Wk
*/ hUGIy(
public Result(Page page, List content){ ~2A<fL,-
this.page = page; sut j
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this.content = content; snj4MA@I]
} zGZe|-
S%&l(=0X
/** O0b8wpFf
* @return Returns the content. 9>@_};l
*/ scL7PxJ5
publicList getContent(){ 3{CGYd]_u
return content; TaM,9MAu
} ]RnX'yw^
*/\dH<
/** RWA|%/L
* @return Returns the page. B5B'H3@
*/ &;9<a^td
public Page getPage(){ /q='~t
return page; 6mdJ
=b#
} Mw'd<{
:g<dwuVO
/** AH=6xtS-
* @param content Y<#7E;aL
* The content to set. XfbkK )d
*/ `!m+g0
public void setContent(List content){ ['-ln)96.
this.content = content; N.eSf
} 7SAu">lIl
oL}FD !}
/** z=)5M*h
* @param page "P<~bw5
* The page to set. E pM
4+
*/ ,{z$M
publicvoid setPage(Page page){ >wcsJ{I
this.page = page; F w{8MQ2
} Zb2 B5(0
} SCxzT}#J
<;9vwSH>
Vg[U4,
`q_7rrkO
RSmxwx^
2. 编写业务逻辑接口,并实现它(UserManager, MiOSSl};
wV56LW
UserManagerImpl) B0Z*YsbXL
java代码: L4kYF~G:4
W97Ka}Y
>+oQxml6nI
/*Created on 2005-7-15*/ 9@D,ZSi
package com.adt.service; I8^z\ef&
j-{WPJa4\
import net.sf.hibernate.HibernateException; 8-8=
\
,u]kZ ]
import org.flyware.util.page.Page; J_P2% b=C
4TR:bQZs
import com.adt.bo.Result; XTW/3pB
y'pG'"U]_
/** U?|s/U
* @author Joa (Z `Y
*/ +oQ@E<)H
publicinterface UserManager { M5) 6|T
=:a3cr~
public Result listUser(Page page)throws pm )A*][s
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HibernateException; 8KoPaq
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} iv;;GW{2
7CG_UB
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ku
;#xhlR* ~
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java代码: L7Skn-*tnA
(x=NA
)
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/*Created on 2005-7-15*/ #lVVSrF,-
package com.adt.service.impl; kP;Rts8JD
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i
import java.util.List; D]oS R7h
54}s:[O
import net.sf.hibernate.HibernateException; .-Ao%A W
Lwv9oa|
import org.flyware.util.page.Page; +U6!
bu>C
import org.flyware.util.page.PageUtil; TD3R/NP
_bMs~%?~/
import com.adt.bo.Result; 'Y"q=@Ei9
import com.adt.dao.UserDAO; vkR"A\:
import com.adt.exception.ObjectNotFoundException; ![Jxh,f
import com.adt.service.UserManager; }){hQt7
;\iQZ~
/** lXz<jt@5
* @author Joa cIgFSwQ4
*/ X)uT-F y
publicclass UserManagerImpl implements UserManager { J-,T^Wv
bq
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private UserDAO userDAO; l_}c[bAUu
/-4%ug tD$
/** a<\m`
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* @param userDAO The userDAO to set. @ObsW!g
*/ p(x[zn+%Y
publicvoid setUserDAO(UserDAO userDAO){ fwl
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this.userDAO = userDAO; "ht2X
w
} 7x1jpQ-
zxsnrn;|
/* (non-Javadoc) \<z{@
* @see com.adt.service.UserManager#listUser ]q?<fEG2<
{=R=\Y?r&
(org.flyware.util.page.Page) $!fz87-p>
*/ J\ 3~
public Result listUser(Page page)throws +w}5-8mH&>
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HibernateException, ObjectNotFoundException { TAGqRYgi
int totalRecords = userDAO.getUserCount(); &_-~kU1K^
if(totalRecords == 0) 1P[!B[;c
throw new ObjectNotFoundException 4s$))x9p
da2BQ;
("userNotExist"); 52%.^/
page = PageUtil.createPage(page, totalRecords); wPG3Ap8L
List users = userDAO.getUserByPage(page); !J6k\$r
returnnew Result(page, users); Crey}A/N
} 'vCFT(C-
b9\=NdyCY
} lR-4"/1|y
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\
isDr|g$S
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 nq$^}L3&~
L:%h]-
询,接下来编写UserDAO的代码: 0,VbB7 z
3. UserDAO 和 UserDAOImpl: thq(tK7
java代码: I/'jRM
5B@&]-'~
B6ys5eQ
/*Created on 2005-7-15*/ s=KA(4p
package com.adt.dao; ,Ma$:6`f
61wGIN2,
import java.util.List; -$mzzYH
<GR]A|P
import org.flyware.util.page.Page; ZB%7Sr0
w1iQ#.4K_
import net.sf.hibernate.HibernateException; \9 ^wM>U
8~4{e,} ,
/** 7W 4[1
* @author Joa sM-k,0z
*/ 0gnr@9,X
publicinterface UserDAO extends BaseDAO { ?N`W,
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publicList getUserByName(String name)throws YgVZq\AV"
Y%Saz+
HibernateException; Lo !kv*
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publicint getUserCount()throws HibernateException; ThFI=K
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publicList getUserByPage(Page page)throws q`qbaX\J3
|~uCLf>
HibernateException; L-$GQGk{
*!B,|]wq=
} /oh[Nu1D
eLl;M4d
RX#:27:
g.z/%LpK
i5:fn@&
java代码: J/)Q{*`_
%"{SGp
1vQ*Br
/*Created on 2005-7-15*/ ZfIQ Fh>
package com.adt.dao.impl; gl HHr
HQ4o^ WC
import java.util.List; Wny{qj)=
?HU(0Vgn'
import org.flyware.util.page.Page; ?n[+0a:8E
Y2Y/laD
import net.sf.hibernate.HibernateException; :5p`H
import net.sf.hibernate.Query; W${0#qq
Xi$uK-AHpj
import com.adt.dao.UserDAO; S{&;
_W&.{
7
/** (?oK+,v?L
* @author Joa 7TlOF
*/ .p <!2
public class UserDAOImpl extends BaseDAOHibernateImpl 3rOv j&2
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implements UserDAO { ])vM# f
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/* (non-Javadoc) Dy0RZF4_
* @see com.adt.dao.UserDAO#getUserByName i?||R|>;"'
5Vf#(r f
(java.lang.String) 7)<&,BWc
*/
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publicList getUserByName(String name)throws Sh=z
n{=vP`V_
HibernateException { lP0'Zg(
String querySentence = "FROM user in class +.gZILw
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com.adt.po.User WHERE user.name=:name"; | [P!9e
Query query = getSession().createQuery $M#G;W5c
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(querySentence); O*T(aM3r
query.setParameter("name", name); ,D;d#fJ
return query.list(); Pe~[qETv
} X`#vH8
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/* (non-Javadoc) -PoW56
* @see com.adt.dao.UserDAO#getUserCount() _-^a8F>/19
*/ qgDd^0
publicint getUserCount()throws HibernateException { j%Usui<DL
int count = 0; +<&_1%5+
String querySentence = "SELECT count(*) FROM f6u<.b
p~BEz?e
user in class com.adt.po.User"; [Vc8j&:L
Query query = getSession().createQuery 1Sx2c
RMDzPda.
(querySentence); !CY:XQm
count = ((Integer)query.iterate().next ~"#qG6dP
?7*.S Lt
()).intValue(); 5{L~e>oS9
return count; ]]V|[g&aJ
} ?
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(gQP_Oa(
/* (non-Javadoc) Rcc9Tx(zvQ
* @see com.adt.dao.UserDAO#getUserByPage xo
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3c}@_Yn
(org.flyware.util.page.Page) fl9`Mgu
*/ 3fM8W>
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publicList getUserByPage(Page page)throws Iw~R@,
WBK6Ug
HibernateException { BF
b<"!Y
String querySentence = "FROM user in class T]HeS(
))66_bech
com.adt.po.User"; QVJq% P
Query query = getSession().createQuery ,` 6O{Z~
2Jo|]>nl}u
(querySentence); kNR -eG
query.setFirstResult(page.getBeginIndex()) F2QFQX(j
.setMaxResults(page.getEveryPage()); ~}pc&jz>q
return query.list(); _Dr9 w&;<
} 8BE] A_X
%|AebxB'o
} m}hEi
^CO{86V
c#(Hh{0
XXPn)kmWR
vhIZkz!9
至此,一个完整的分页程序完成。前台的只需要调用 ;-#2p^
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userManager.listUser(page)即可得到一个Page对象和结果集对象 FUzN}"\1
JlR$"GU
的综合体,而传入的参数page对象则可以由前台传入,如果用 ~@ =(#tO.
SO4?3wg7
webwork,甚至可以直接在配置文件中指定。 \Kr8k`f
2*Zk^h=
下面给出一个webwork调用示例: G%iTL"6
java代码: )Fon;/p
=gNPS0H
n&OM~Vs
/*Created on 2005-6-17*/ '.EO+1{a
package com.adt.action.user; mX 3p
>m]LV}">O
import java.util.List; J?{@pA
_Ne fzZWUJ
import org.apache.commons.logging.Log; ~-R%m
import org.apache.commons.logging.LogFactory; mC2K &'[
import org.flyware.util.page.Page; ~(nc<M[
76H>ST@G|
import com.adt.bo.Result; >Q$ph=
import com.adt.service.UserService; l^F ?^kP
import com.opensymphony.xwork.Action; dq,j?~ _}
Yw] 7@
/** plL|Ubn
* @author Joa
J-#V_TzJ?
*/ NNt
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publicclass ListUser implementsAction{ i/j53towe
&S,_Z/BS;
privatestaticfinal Log logger = LogFactory.getLog 0vETg'r
vjjVZ
(ListUser.class); Z_Wzm!:
`AYq,3V
private UserService userService; }@eIO|
Hz\@#
private Page page; m/z,MT74*J
w 5 yOSz
privateList users; Nv=78O1
&1(- 8z*
/* X NgcBSD
* (non-Javadoc) i.k7qclL`
* 8EI9&L>
* @see com.opensymphony.xwork.Action#execute() 8~tX>q<@q
*/ U%q-#^A
publicString execute()throwsException{ F+"_]
Result result = userService.listUser(page); * xCY^_
page = result.getPage(); h PL]B_<
users = result.getContent(); }R`Rqg-W
return SUCCESS; |lt]9>|
} ,AmwsXN"F
)/?H]o$NU
/** Aa=:AkrH
* @return Returns the page. AdVc1v&>
*/ q.p.$)
public Page getPage(){ ,jOJ\WXP
return page; 8[;vC$
} ,DZvBS
v\GVy[Qyv
/** M?!@L:b[
* @return Returns the users. #=t/wAE y:
*/ T]ls&cW5
publicList getUsers(){ u<Y#J,p`e
return users; =*&[K^
} l|=4FIMD
+LF#XS@
/** w8XCU>
|
* @param page f. "\~
* The page to set. xNzGp5H
*/ N ai5!_'
publicvoid setPage(Page page){ ?u|@,tQ[
this.page = page; CJ*
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} _Z23lF9
8LbwEKl
/** XEgJ7h_
* @param users VGmvfhf#"
* The users to set. 6|zhqb|s
*/ 5BJE
publicvoid setUsers(List users){ -~mgct5
this.users = users; )V\@N*L`ik
} TWzLJ63*
1h&`mqY)L.
/** IdQ./@?
* @param userService %WgN+A0
* The userService to set. b~J)LXj]w
*/ 1~*1W4};F8
publicvoid setUserService(UserService userService){ Zge(UhZ
this.userService = userService; b,Oh8O;>
} .qgUD
} Zz0e4C
G18w3BFx
]K"&Vd
O\6U2b~
GC{M"q|_
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, JVYH b 60Z
#;$]M4
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 xWxc1tT`
9 3>4n\
么只需要: Qc; kj
java代码: x@t?7 o\&
gcU*rml
2yZr!Rb~*
<?xml version="1.0"?> "f,{d}u
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork lH}KFFbp
$KK~KEZ2
1.0//EN" "http://www.opensymphony.com/xwork/xwork- )S
caT1I
p+;& Gg54
1.0.dtd"> qhEv6Yxfw6
FQ]/c#J
<xwork> zaqX};b
xG9Sk
<package name="user" extends="webwork- >?, Zn
;]u9o}[
2
interceptors"> VPe0\?!d
FEaT}/h;
<!-- The default interceptor stack name ?, S/>SP
DN*5q9.
--> l3>S{
<default-interceptor-ref \84t\jKR
AcC &Q:g
name="myDefaultWebStack"/> yD7BZI
xW
;-+q*@sa]
<action name="listUser" or/gx 3
1~5DIU^
class="com.adt.action.user.ListUser"> qN $t_
<param 0cd_l
2f#g
S6TNu+2w4
name="page.everyPage">10</param> x HRSzYn$
<result bGPE0}b
l/&.H F
name="success">/user/user_list.jsp</result> j/FLEsU!R
</action> ={qcDgn~C
eU[g@Pq:Y
</package> 4:`D3
D 2X_Yv
</xwork> xN 1P#
JvpGxj
]~({;;3o-
Q&} 0owe
L*6'u17y
rbZbj#
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 .%zcm
=V^-@ji)b
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。 l8\UO<^fY
\|]mClj#
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 N3%X>*'
2 !s&|lI
%rzPh<>e
k }=<51c
kZ40a\9
Ye
我写的一个用于分页的类,用了泛型了,hoho Zf'*pp T&q
z
p E|
java代码: apvcWF%
eS`VI+=@0
%FO{:@CH
package com.intokr.util; O tG\Uw8
rE3dHJN;
import java.util.List; {& o^p!
UUah5$Iy
/** i0vm00oT
* 用于分页的类<br> D(!^$9e9b
* 可以用于传递查询的结果也可以用于传送查询的参数<br> X8nos
* o
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* @version 0.01 : T*Q2
* @author cheng BOs/:ZbK0W
*/ Shm> r@C?
public class Paginator<E> { /^.|m3
privateint count = 0; // 总记录数 KZm&sk=QM-
privateint p = 1; // 页编号 aurs~
privateint num = 20; // 每页的记录数 2u"lc'9v
privateList<E> results = null; // 结果 1F@k9[d~
=BJe)!b
/** +r:g }iR
* 结果总数 iUx\3d,
*/ .tngN<f
publicint getCount(){ ~zVxprEf_
return count;
hAGHb+:
} YH&=cI@
z/@_?01T=
publicvoid setCount(int count){ 1U 6B$(V^i
this.count = count; 7]ieBUfS
} 0> f!S` *
iOE. .xA:
/** K7
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* 本结果所在的页码,从1开始 [a=exK
* Y
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* @return Returns the pageNo. } M#e\neii
*/ ,g*!NK_:5t
publicint getP(){ S@qp_!
return p; +>$]leqa
} Q;h.}N8W
_Nx
/<isdL
/** e#"h@kZP
* if(p<=0) p=1 $|K
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* aeqz~z2~8s
* @param p VYvfx
*/ K_7pr~D]@r
publicvoid setP(int p){ %y1!'R:ZW
if(p <= 0) jc^QWK*q
p = 1; Lb*KEF% s
this.p = p; ^ Ltho`
} Q8p6n
.Y)[c.,j
/** !Ok(mgV$/
* 每页记录数量 j8Z, :op
*/ U1RU2M]v
publicint getNum(){ Q$jEmmm%V[
return num; Dk1& <} I
} 5!-TLwl`j\
%fS9F^AK
/** Oy6fl'FIt
* if(num<1) num=1 n3^(y"q
*/ ho]:)!|VY
publicvoid setNum(int num){ jHLs
5%
if(num < 1) D=tZ}_'{t
num = 1; &q