Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 X>8,C^~$1
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 M@R"-$Z
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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 Ea&|kO|
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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 xIGq+yd(
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分页支持类: rW)h?, b
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java代码: pcy;]U?
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package com.javaeye.common.util; kJJT`Ba&/
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import java.util.List; 5dm ~yQN/
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publicclass PaginationSupport { o]4]fLQ
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publicfinalstaticint PAGESIZE = 30; j(=w4Sd_W
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privateint pageSize = PAGESIZE; (-gomn
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privateList items; f' ?/P~[
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privateint totalCount; n9'3~qVZ
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privateint[] indexes = newint[0]; riDb!oC
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privateint startIndex = 0; wXKtQ#o}
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public PaginationSupport(List items, int =]%JTGdp(
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totalCount){ |NuMDVd+s
setPageSize(PAGESIZE); Wef%f]u
setTotalCount(totalCount); C|V7ZL>W
setItems(items); ;Z]Wj9iY
setStartIndex(0); w"v!+~/9
} r{;NGQYs
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public PaginationSupport(List items, int 3YHEH\60^
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totalCount, int startIndex){ 8zp?WUb
setPageSize(PAGESIZE); 4j={ 9e<
setTotalCount(totalCount); V4[-:k
setItems(items); 'z ?Hv
setStartIndex(startIndex); x4WCAqi/2
} cUY-
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public PaginationSupport(List items, int eFG/!b<17
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totalCount, int pageSize, int startIndex){ ;P91'B~t
setPageSize(pageSize); PVI Oe}N
setTotalCount(totalCount); /65YHXg,
setItems(items); -G(me"Cu
setStartIndex(startIndex); j'D%eQI,V
} WXy8<?s
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publicList getItems(){ w"j>^#8
return items; i#'K7XM2
} MgeC-XQM
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publicvoid setItems(List items){ o701RG~)
this.items = items; csy6_q(
} RlOy,/-<
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publicint getPageSize(){ g(@F`W[
return pageSize; ^Hx}.?1
} 7hHID>,o9%
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publicvoid setPageSize(int pageSize){ TxJk.c
this.pageSize = pageSize; OG5{oH#K
} t#^Cem<
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publicint getTotalCount(){ tu\XuDky
return totalCount; #_DpiiS,.Q
} tgF~5
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publicvoid setTotalCount(int totalCount){
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if(totalCount > 0){ ~<[+!&<U
this.totalCount = totalCount; =-r"@2HBq
int count = totalCount / if*V-$[I
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pageSize; 2P"643tz
if(totalCount % pageSize > 0) LKM018H>
count++; JWNN5#=fQ
indexes = newint[count]; WZ'<iI
for(int i = 0; i < count; i++){ >V"{]v
indexes = pageSize * 9<gW~
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} ?MH=8Cl1w
}else{ [U&k"s?
this.totalCount = 0; _}F&^
} *j3U+HV
} @NM0ILE
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publicint[] getIndexes(){ &]TniQH
return indexes; bJ:5pBJ3
} > "hP
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publicvoid setIndexes(int[] indexes){ d:'{h"M6
this.indexes = indexes; *$A`+D9
} hkPMu@BI
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publicint getStartIndex(){ c}@E@Y`@w
return startIndex; I'5[8
} T\gs
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publicvoid setStartIndex(int startIndex){ %e:+@%]
if(totalCount <= 0) F@<cp ?dR
this.startIndex = 0; >g$iO`2
elseif(startIndex >= totalCount) 1)~|{X+~
this.startIndex = indexes O C&BJNOi
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[indexes.length - 1]; f&vMv.
elseif(startIndex < 0) jRsl/dmy
this.startIndex = 0; Tb]7# v
else{ z};|.N}
this.startIndex = indexes ja9u?UbW
-
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[startIndex / pageSize]; v.RA{a 9
} -|V#U`mwF
} }1 O"?6
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publicint getNextIndex(){ S<T'B0r8
int nextIndex = getStartIndex() + KH2]:&6:Q
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pageSize; `oMZ9Gq2E
if(nextIndex >= totalCount) "}X+vd``
return getStartIndex(); /4+L2O[
else 9wx]xg4l"
return nextIndex; G ]h
} Ry+?#P+
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publicint getPreviousIndex(){ uihH")Mo
int previousIndex = getStartIndex() - OG{*:1EP
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pageSize; y{M7kYWtHV
if(previousIndex < 0) r1HG$^
return0; P].Eb7I
else >~ *wPoW
return previousIndex; ,|*Gr"Q=
} huZ5?'/Fg
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} q]1p Q)\'p
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抽象业务类 (c0L@8L
java代码: |cd"cx+
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/** !n;3jAl&$
* Created on 2005-7-12 <<-L,0
*/ w7`pbcY,
package com.javaeye.common.business; S0StC$$1
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import java.io.Serializable; U?dad}7
import java.util.List; 6Gg`ExcT5
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import org.hibernate.Criteria; [Q:mq=<Z%
import org.hibernate.HibernateException; =oVC*b
import org.hibernate.Session; &yP|t":HWX
import org.hibernate.criterion.DetachedCriteria; $%$zZJ@/
import org.hibernate.criterion.Projections; </'n={+q
import 0xZ^ f}@L
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org.springframework.orm.hibernate3.HibernateCallback; J#Q>dC7
import :^W}$7$T
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org.springframework.orm.hibernate3.support.HibernateDaoS yR~$i3Z*
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upport; Y*#xo7#B
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import com.javaeye.common.util.PaginationSupport; >NPK;Vu
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public abstract class AbstractManager extends k5>UAea_
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HibernateDaoSupport { 48z%dBmTT*
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privateboolean cacheQueries = false; TfJ*G6\7e#
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privateString queryCacheRegion; t;Z9p7rk
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publicvoid setCacheQueries(boolean )^8[({r~
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cacheQueries){ p8XvfM
this.cacheQueries = cacheQueries; 4RctYMz
} _N:$|O#
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publicvoid setQueryCacheRegion(String v5@4|u3ds
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queryCacheRegion){ X9PbU1o;
this.queryCacheRegion = )a0l:jEOc
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queryCacheRegion; r]-n,
} Ae=JG8Ht~
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publicvoid save(finalObject entity){ <V)z{uK
getHibernateTemplate().save(entity); NA$)qX_
} u`wD6&y*
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publicvoid persist(finalObject entity){ KaMg[G
getHibernateTemplate().save(entity); p*<I_QM!
} 4r83;3WXs
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publicvoid update(finalObject entity){ _'mC*7+
getHibernateTemplate().update(entity); j=U"t\{
} EZ>(}
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publicvoid delete(finalObject entity){ N"<.v6Z
getHibernateTemplate().delete(entity); |%5pzYe
} O*/%zr
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publicObject load(finalClass entity, IAzFwlO9
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finalSerializable id){ .Y2Hd$rs
return getHibernateTemplate().load NRG06M
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(entity, id); $Tv~ *|a
} ,d*1|oUw
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publicObject get(finalClass entity, Y,L[0%
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finalSerializable id){ prt(xr4@
return getHibernateTemplate().get qi~-<qW
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(entity, id); 1`|Z8Jpocj
} 0827z
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publicList findAll(finalClass entity){ m+8:_0x "
return getHibernateTemplate().find("from :FU?vh$)
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" + entity.getName()); (X^,.qy
} s>G]U)d<'
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publicList findByNamedQuery(finalString WI| -pzg
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namedQuery){ Bx\ o8k
return getHibernateTemplate ugXDnM[S%
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().findByNamedQuery(namedQuery);
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} PA803R74
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publicList findByNamedQuery(finalString query, 9W(&g)`
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finalObject parameter){ |J`v
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return getHibernateTemplate w%TrL+v
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().findByNamedQuery(query, parameter); ts(u7CJd
} Gjq7@F'
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publicList findByNamedQuery(finalString query, SJX9oVJeZ
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finalObject[] parameters){ 4 a&8G
return getHibernateTemplate eD(5+bm
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().findByNamedQuery(query, parameters); {[:C_Up)f
} raOuD3
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publicList find(finalString query){ |*w)]2Bl
return getHibernateTemplate().find rZ+4kf6S
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(query); x&J\ swN9
} KwMt@1Z
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publicList find(finalString query, finalObject k7@QFw4 j
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parameter){ @=AQr4&
return getHibernateTemplate().find 'MX|=K!C
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(query, parameter); o:cTc:l)
} @,= pG
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public PaginationSupport findPageByCriteria p),*4@2<
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(final DetachedCriteria detachedCriteria){ A0@,^|]
return findPageByCriteria FXY>o>K%h
A{-S )Z3}
(detachedCriteria, PaginationSupport.PAGESIZE, 0); fnr8{sr.2Z
} OESKLjFt
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public PaginationSupport findPageByCriteria *^g]QQ
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(final DetachedCriteria detachedCriteria, finalint { Mb<onW
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startIndex){ &R.5t/x_
return findPageByCriteria ORP<?SG55u
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(detachedCriteria, PaginationSupport.PAGESIZE, tboQn~&4
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startIndex); q,#s m'S
} G Wa6FX:/
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public PaginationSupport findPageByCriteria 'ParMT
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(final DetachedCriteria detachedCriteria, finalint 6Hb a@Q1`
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pageSize, 6~ y'
finalint startIndex){ KC; o
return(PaginationSupport) Wk3-J&QbS
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getHibernateTemplate().execute(new HibernateCallback(){ r{d@74
publicObject doInHibernate h*JN0O<b
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(Session session)throws HibernateException { P}a$#a'!
Criteria criteria = q$yg^:]2
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detachedCriteria.getExecutableCriteria(session); =AzkE]
int totalCount = 'xai5X
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((Integer) criteria.setProjection(Projections.rowCount S}h
d, "I
4<}@hk
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()).uniqueResult()).intValue(); "]p&7
criteria.setProjection DFZ@q=ZT
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(null); HH6H4K3Zj
List items = ^|vk^`S
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criteria.setFirstResult(startIndex).setMaxResults r|ZB3L|7
$$0<
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(pageSize).list(); t1
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PaginationSupport ps = e~)4v
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new PaginationSupport(items, totalCount, pageSize, zb[kRo&a0W
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startIndex); PCgr`($U
return ps; ]Z\ W%'q+
} l}-k>fug
}, true); ziO(`"v
} [cEGkz
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public List findAllByCriteria(final &,PA+#
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DetachedCriteria detachedCriteria){ [ywF!#'){
return(List) getHibernateTemplate Mi(6HMA.SF
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().execute(new HibernateCallback(){ FdnLxw
publicObject doInHibernate [bo"!Qk%
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(Session session)throws HibernateException { cy
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Criteria criteria = .Xf_U.h$*@
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detachedCriteria.getExecutableCriteria(session); *UW 8|\;
return criteria.list(); BH^*K/^
} $,r%@'= &
}, true); 0)h.[O8@>
} {U3jJ#K
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public int getCountByCriteria(final `g(#~0R
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DetachedCriteria detachedCriteria){ x~Z7p)D_<
Integer count = (Integer) {P?DkUO}
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getHibernateTemplate().execute(new HibernateCallback(){ t'W6Fmwkx
publicObject doInHibernate B[8RBTsA
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(Session session)throws HibernateException { [D+PDR
Criteria criteria = GFbn>dY
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detachedCriteria.getExecutableCriteria(session); <x;g9Z>(
return jM6$R1HX
]
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criteria.setProjection(Projections.rowCount B&59c*K
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()).uniqueResult(); .@mZG<vg
} s/~[/2[bnf
}, true); RDQ]_wsyKG
return count.intValue(); zn= pm#L
} t W
} V?^qW#AG
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用户在web层构造查询条件detachedCriteria,和可选的 "tk1W>liIN
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ;{iTSsb
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PaginationSupport的实例ps。 Z9% u,Cb
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ps.getItems()得到已分页好的结果集 >yVrIko
ps.getIndexes()得到分页索引的数组 ^56D)A=
ps.getTotalCount()得到总结果数 3#udzC
ps.getStartIndex()当前分页索引 d1^5r
31
ps.getNextIndex()下一页索引 ^"/TWl>jB
ps.getPreviousIndex()上一页索引 *CF80DJ
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 vft7-|8T
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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 #|:q"l9
#X!seQ7a
一下代码重构了。 ],R\oMYy|P
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我把原本我的做法也提供出来供大家讨论吧: 1T~`$zS7
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首先,为了实现分页查询,我封装了一个Page类: =.m/X>
java代码: srImk6YD
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/*Created on 2005-4-14*/ ZS_
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package org.flyware.util.page; T|YMU?4
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/** 98zJ?NaD&
* @author Joa UNrO$aX!1'
* ph2
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*/ Vn/FW?d7
publicclass Page { |N^8zo :
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/** imply if the page has previous page */ %_5?/H@%3z
privateboolean hasPrePage; iY sQ:3s
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/** imply if the page has next page */ ),
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privateboolean hasNextPage; 9a1R"%Z
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/** the number of every page */ Esj1Vv#
privateint everyPage; ^q}phj3E
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/** the total page number */ a[!:`o1U
privateint totalPage; V2 ;?
pnv)D}"
/** the number of current page */ ESS1 L$y
privateint currentPage; X1u\si%.4S
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/** the begin index of the records by the current h2+"e# _
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query */ e5n"(s"G*[
privateint beginIndex; +rrA>~
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/** The default constructor */ ?FZ)
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public Page(){ mI^S% HT
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} uD4W@*PYr
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/** construct the page by everyPage -7I%^u
* @param everyPage J]NMqiq
* */ bSTTr<W
public Page(int everyPage){ z=rSb4"W
this.everyPage = everyPage; >dDcm
} mLHl]xs4
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b(KR
/** The whole constructor */ !i{5mc\
public Page(boolean hasPrePage, boolean hasNextPage, @GQtyl;q
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int everyPage, int totalPage, @_#]7
int currentPage, int beginIndex){ qs
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this.hasPrePage = hasPrePage; u@4khN:
^p
this.hasNextPage = hasNextPage; 0SZ:C(]
this.everyPage = everyPage; B-$ps=G+z
this.totalPage = totalPage; /5f=a
this.currentPage = currentPage; cdL0<J b,
this.beginIndex = beginIndex; |Yi_|']#
} \&v)#w
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/** #Y'ub
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* @return [&p/7
* Returns the beginIndex. |L
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*/ #J$z0%P
publicint getBeginIndex(){ C8 $KVZ
return beginIndex; TPi{c_
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} j'SGZnsy*
4"+v:t)z6{
/** <+<,$jGC-
* @param beginIndex v +?'/Q%
* The beginIndex to set. GRgpy
*/ )Y=ti~?M(
publicvoid setBeginIndex(int beginIndex){ !@)tkhP
this.beginIndex = beginIndex; drB$q[Ak9
} (%]M a
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/** 3+vMi[YO
* @return h& Ezhv2
* Returns the currentPage. <ZoMKUuB
*/ ^%33&<mB}
publicint getCurrentPage(){ 6.3qux9
return currentPage; #4& <d.aw'
} AT"!Ys|
jXyK[q&O&
/** kl5Y{![/&f
* @param currentPage A^7}:[s20
* The currentPage to set. :rN5HOg^9
*/ 7}Jn`^!
publicvoid setCurrentPage(int currentPage){ MBFn s/
this.currentPage = currentPage; }Szs9-Wns
} ]ex2c{
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/** arn7<w0
* @return o{MmW~/o&
* Returns the everyPage. g+ cH
*/ J['?ud}@
publicint getEveryPage(){ |
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return everyPage; 8ao>]5Rs3
} ztaSIMZ
^ Mq8jw(2
/** P)06<n1">Z
* @param everyPage %T~LK=m
* The everyPage to set. +?C7(-U>
*/ 8wzQr2:
publicvoid setEveryPage(int everyPage){ wgKM6?
this.everyPage = everyPage; $"{I|UFC
} ^cI RP
@9h6D<?
/** [F^j(qTR
* @return e:iqv?2t
* Returns the hasNextPage. J<ZG&m362p
*/ /h K/t;
publicboolean getHasNextPage(){ iaQ3mk#
return hasNextPage; m/1;os5+8
} R-BN}ZS
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/** !;&{Q^}
* @param hasNextPage MZ<BCRB
* The hasNextPage to set. (L7%V !
*/ +C`zI~8
publicvoid setHasNextPage(boolean hasNextPage){ R"{oj]d;$F
this.hasNextPage = hasNextPage; ,) 3Eog\-
} 0d #jiG
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/** YR0.m%U,
* @return x`zE#sD
* Returns the hasPrePage. kwpbg Q
*/ jsIT{a*]
publicboolean getHasPrePage(){ SHUn<+/e
return hasPrePage; jRSY`MU}t+
} zFO#oW,D
]*yUb-xY
/** sj% \lq
* @param hasPrePage hXP'NS`iv
* The hasPrePage to set. o<i\1<eI
*/ ,V #r
publicvoid setHasPrePage(boolean hasPrePage){ ey) 8q.5
this.hasPrePage = hasPrePage; "I^pb.3
} "I&,':O+
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/** n~v*
* @return Returns the totalPage. bc*CP0t|
* #TG.weTC
*/ FK`M+ j
publicint getTotalPage(){ S1d{! ` 3
return totalPage; G297)MFF
} C_V5.6T!
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/**
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* @param totalPage ?H(']3X5@
* The totalPage to set. =sh]H$
*/ ?89_2W
publicvoid setTotalPage(int totalPage){ :P20g](
this.totalPage = totalPage; Mp`i@pm+
} [[vb w)u
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} !1ZrS
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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 'n4
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个PageUtil,负责对Page对象进行构造: qZ DP-
java代码: dp#'~[ j
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/*Created on 2005-4-14*/ n*vhCeL
package org.flyware.util.page; Ox}a\B8
J={IGA
import org.apache.commons.logging.Log; l*>,:y
import org.apache.commons.logging.LogFactory; }Jk=ZBVjT7
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/** Vh5Z'4N
* @author Joa B/ACU
* E3,Nc`'m9
*/ f|-%.,
publicclass PageUtil { uUI@!)@2
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privatestaticfinal Log logger = LogFactory.getLog gC\^"m
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(PageUtil.class); D;WQNlTU
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/** Dro2R_j{
* Use the origin page to create a new page b;Uqyc
* @param page +C){&/=#
* @param totalRecords u(Y?2R
* @return Y SD|#0
*/ 4WZ"8
publicstatic Page createPage(Page page, int L&h90Az1W
/yO|Q{C}M8
totalRecords){ \N"=qw^ t
return createPage(page.getEveryPage(), w2e9Ue~WH
+'QE-#%{=
page.getCurrentPage(), totalRecords); ^%~ux0%^T
} ZT%Q:]B+
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/** ?_Y2'O
* the basic page utils not including exception VqK/GWg
!_#2$J*s^D
handler
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* @param everyPage 2C_/T8
* @param currentPage ;Zow C#j
* @param totalRecords f<v:Tg.[
* @return page J}3 7 9
*/ bO\E)%zp
publicstatic Page createPage(int everyPage, int l!YjDm{E
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currentPage, int totalRecords){ m*Q*{M_e
everyPage = getEveryPage(everyPage); bf1EMai"
currentPage = getCurrentPage(currentPage); "fX9bh^
int beginIndex = getBeginIndex(everyPage, m03]SF(#3
(n3MbVi3LU
currentPage); RYem(%jq
int totalPage = getTotalPage(everyPage, Z/w "zCd
x;p7n2_
totalRecords); 47
*,
boolean hasNextPage = hasNextPage(currentPage, [Uw/;Kyh
z9)I@P"
totalPage); L>Soj|WUy(
boolean hasPrePage = hasPrePage(currentPage); U|}Bk/0.
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returnnew Page(hasPrePage, hasNextPage, ?wQaM3 |^:
everyPage, totalPage, =`%"-A
currentPage, [W{WfJ-HwG
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beginIndex);
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} @#= ail
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privatestaticint getEveryPage(int everyPage){ pz]#/Ry?
return everyPage == 0 ? 10 : everyPage; Zbobi,
} ppu WcGo
:*MqYny&
privatestaticint getCurrentPage(int currentPage){ >qhoGg
return currentPage == 0 ? 1 : currentPage; zOzobd
} ^ H )nQ
re;^,
privatestaticint getBeginIndex(int everyPage, int HHU0Nku@ho
Q1?09
currentPage){ sGdlS&08(
return(currentPage - 1) * everyPage; Az"(I>VfD
} }"CX`
[[sfuJD
privatestaticint getTotalPage(int everyPage, int R x>>0%e.
6 (@U+`
totalRecords){ 6~_TXy/
int totalPage = 0; rfVHPMD0
P&0o~@`cL
if(totalRecords % everyPage == 0) I"1H]@"=
totalPage = totalRecords / everyPage; mcB8xE
else /9..hEq^
totalPage = totalRecords / everyPage + 1 ; NiCB.a
!?u{2D
return totalPage; ~gAp`Q
} q!+&|F
L 2k?Pl
privatestaticboolean hasPrePage(int currentPage){ <5wk~|@t
return currentPage == 1 ? false : true;
<B%s9Zy
} V<%eWT)x7C
9;*-y$@
privatestaticboolean hasNextPage(int currentPage, &>]c"?C*
;5(ptXX1W
int totalPage){ 8vL2<VT;
return currentPage == totalPage || totalPage == 2y0J~P! I
,m)k;co^
0 ? false : true; !QTfQ69Y0
} ;@R=CQ6
2GRdfX
]s))O6^f
}
l,n
V*Z
1ae,s{|
GV"Hk E;
VX<jg #(
-4!9cE
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。 l#;DO9
2iJ)K rw
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 >.)m|,
:g`j
gn0
做法如下: ][IEzeI_LN
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 )* \N[zm
d}2$J1`
的信息,和一个结果集List: wG\ +C'&~
java代码: Jiv%Opo/|
WE|-zo
'zg; *)x1/
/*Created on 2005-6-13*/ wcI?.
package com.adt.bo; S);SfNh%CL
i:coNK)4
import java.util.List; qP}187Q1
+%%Ef]
import org.flyware.util.page.Page; }+{?
Ms
} qf=5v
/** C=6.~&(
* @author Joa X*^^W_LH.
*/ $k|:V&6SV
publicclass Result { :p@.aD5
&Oih#I
private Page page; jrKRXS
UbnX%2TW
private List content; Hido[
?2zbZ
/** v,VCbmc
* The default constructor $xK2M
*/ 'fGB#uBt
public Result(){ ip`oL_c
super(); jrl'?`O
} y|7sh
~.*G%TW &V
/** .a0]1IkatV
* The constructor using fields $k,wA8OZ-
* &P@dx=6d
* @param page Q,f~7IVX
* @param content b-+~D9U<
*/ 0S%xm'|N
public Result(Page page, List content){ z3bRV{{YqN
this.page = page; nN]GO}
this.content = content; 1j!LK-
} )#H&lH
u3B[1Ae:K
/** 6Kbc:wlR
* @return Returns the content. E<~Fi.M;\
*/ o^!_S5zKe.
publicList getContent(){ !'jZ
!NFO
return content; Xj Rk1~
} Biva{'[m
%lbDcEsf9
/** A%[BCY_
* @return Returns the page. s.#%hPX{
*/ |}-bMQ|
public Page getPage(){ .yF@Ow
return page; cOq'MDr
} 0'3f^Ajf
&&daQg4Ha
/** P5K=S.g
* @param content +}.~"
* The content to set. vR)f'+_Nz
*/ s<XAH7?0
public void setContent(List content){ w!j 'k|b>
this.content = content; QH d^?H*
} GI[TD?s
O?=YY@j
/** 2I@d=T{K
* @param page $5]}]
* The page to set. 2I|`j^
*/ +I$,Y~&`>
publicvoid setPage(Page page){ /FthT
this.page = page; Xv&&U@7
} (^@rr[.o7
} ;J>upI
-91*VBrOd
yd|ro G/
Km)VOX[ZZ
d$H
2. 编写业务逻辑接口,并实现它(UserManager, k Xg&}n7
Lhz*o6)
UserManagerImpl) +v.<Fw2k#
java代码: 9zL(PkC%\
$SOFq+-T
L7`=ec<
/*Created on 2005-7-15*/ zzH^xxg
package com.adt.service; m}$7d5
E^`-:L(_
import net.sf.hibernate.HibernateException; ]wZlJK`K
{M^BY,%*
import org.flyware.util.page.Page; [KMNMg
*/6lyODf
import com.adt.bo.Result; TFAd
3cA'9
/** * @=ZzL
* @author Joa $VxKv7:
*/ GiK4LJ~cH)
publicinterface UserManager { E~y(@72)
Vm*E^ v
public Result listUser(Page page)throws >lV'}0u)
ib\_MNIb
HibernateException; Tfz_h~D
E Xxv
} _qO'(DKylC
Tpd|+60g
F+SqJSa
4~K%,K+Du
LG+2?+tE"
java代码: 0sA+5*mdM
KSAE!+
;I/ A8<C
/*Created on 2005-7-15*/ PWBcK_4i%
package com.adt.service.impl; KDS}"/
j>`-BN_
import java.util.List; |pG%]?A
.nzN5FB
U
import net.sf.hibernate.HibernateException; dLfB){>S
KK}ox%j
import org.flyware.util.page.Page; VTwDa*]AhB
import org.flyware.util.page.PageUtil; bgYUsc*uR
NXCvS0/h
import com.adt.bo.Result; %6W%-`
import com.adt.dao.UserDAO; bs&>QsI?j
import com.adt.exception.ObjectNotFoundException; 8Drz
i!}
import com.adt.service.UserManager; gkmV;0
.]e_je_
/** .|e8v _2J
* @author Joa kW7$Gw]-
*/ ]5r@`%9
publicclass UserManagerImpl implements UserManager { !T#EkMM
B#G:aBCM
private UserDAO userDAO; mt]^d;E
4Ql9VM%y
/** #:NY9.\o
* @param userDAO The userDAO to set. lc$wjK[w[
*/ 5HaI$>h6
publicvoid setUserDAO(UserDAO userDAO){ c;Gf$9?iC
this.userDAO = userDAO; SJ2l6
} al" =ld(
f~10 iD
/* (non-Javadoc) bE;c&g
* @see com.adt.service.UserManager#listUser )|=4H>?%
I.[Lv7U-
(org.flyware.util.page.Page) }/lyrjV
*/ w>o/)TTJL
public Result listUser(Page page)throws G*f\
/
+[rQf<*
HibernateException, ObjectNotFoundException { 2FcNzAaV
int totalRecords = userDAO.getUserCount(); brX[-
if(totalRecords == 0) \(MIDCZ@-
throw new ObjectNotFoundException ^
-4~pDv^
9:P\)'y?
("userNotExist"); <L+1
&H
page = PageUtil.createPage(page, totalRecords); fC".K
Yjp
List users = userDAO.getUserByPage(page); !nsx!M
returnnew Result(page, users); %:v<&^oDlm
} ?>Ngsp>-P
k<|}&<h
} 9:*[Q"v
6>]w1
H
;0U*N &
f
aaP6zJXi
iB|htH'T
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 nV`U{}x
DL<;qhte
询,接下来编写UserDAO的代码: U&ytZ7iB
3. UserDAO 和 UserDAOImpl: #jh5% @
java代码: THlQifA!
=I aWf
@,j,GE%
/*Created on 2005-7-15*/ +n<W#O%
package com.adt.dao; "x vizvR
U:z5`z!
import java.util.List; 3RanAT.nu:
@qpj0i+>*
import org.flyware.util.page.Page; (:I]v_qEYS
Qvty;2$o@
import net.sf.hibernate.HibernateException; T 5F)
%fnG v\uI
/** Y1ks'=c>
* @author Joa SpImd IpD
*/ jfiUf1Mj
publicinterface UserDAO extends BaseDAO { B
6z 'Q
/Kh,
publicList getUserByName(String name)throws {-lpYD^k3
ah%Ws#&
HibernateException; <D P8a<{{
$
x:N/mMu`
publicint getUserCount()throws HibernateException;
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q^:VF()d_z
publicList getUserByPage(Page page)throws 5rmU9L
j XH9Pq4
HibernateException; 3FtL<7B'.
\_
} 9;'#,b*(
IJ~j(.W
|RXQ_|
OLqV#i[K#9
b8_F2
java代码: |j-ng;
Jt[,V*:#
LRg]'?
/*Created on 2005-7-15*/ v3aPHf
package com.adt.dao.impl; B]H8^
@({=~
W^
import java.util.List; 7nPcm;Er
F}7sb#G
import org.flyware.util.page.Page; 5.*,IedY
? 3OfiGX?
import net.sf.hibernate.HibernateException; X i1|%
import net.sf.hibernate.Query; >[Wjzg
0k{\W
import com.adt.dao.UserDAO; b"Q8[k |d
YVwpqOE.=
/** Xl<iR]lda
* @author Joa |iI
dm
*/ bU}v@Uk
public class UserDAOImpl extends BaseDAOHibernateImpl x\U[5d
^Fh*9[Zf$
implements UserDAO { 1*yxSU@uY
SDC'S]{ew
/* (non-Javadoc) N[e,%heR
* @see com.adt.dao.UserDAO#getUserByName 5 ty2e`~K
/IG{j}
(java.lang.String) Eamt_/LKf
*/ lKw-C[
publicList getUserByName(String name)throws B,cFvS
e.skE>&
HibernateException { |$b8(g$s)
String querySentence = "FROM user in class y]0O"X-G
x};~8lGT>t
com.adt.po.User WHERE user.name=:name"; >x JzV
Query query = getSession().createQuery ~1%*w*
IJ&Lk=2E]
(querySentence); W-l+%T!
query.setParameter("name", name); L7Hv)
return query.list(); v@soS1V!
} o0]YDX@T
= V2Rq(jH
/* (non-Javadoc) O-X(8<~H=
* @see com.adt.dao.UserDAO#getUserCount() Xg96I:r'p
*/ :Y\ ~[Y
publicint getUserCount()throws HibernateException { **L&I5Hhm
int count = 0; W`_JERo
String querySentence = "SELECT count(*) FROM 1,%`vlYv
F5qA!jZ1]
user in class com.adt.po.User"; \1jThJn
Query query = getSession().createQuery yAryw{(
H oABo:
(querySentence); ?UAuUFueA
count = ((Integer)query.iterate().next C[<}eD4bV
{KNaJ/:>W
()).intValue(); 9gcW;
return count; {#qUZ z-
} zPa2fS8
~c35Y9-5
/* (non-Javadoc) JI[8n$pr]
* @see com.adt.dao.UserDAO#getUserByPage -0d9,,c
eO <N/?t
(org.flyware.util.page.Page) S(Af o`
*/ |E7J5ha
publicList getUserByPage(Page page)throws \Q|-Npw
ZK8)FmT_<O
HibernateException { ]JjS$VMauX
String querySentence = "FROM user in class X|T|iB,vT
!xfDWbvHV
com.adt.po.User"; SjB"#E)
Query query = getSession().createQuery \jwG*a
1H-Y3G>jN
(querySentence); B18BwY
query.setFirstResult(page.getBeginIndex()) T0tX%_6`
.setMaxResults(page.getEveryPage()); Y2x|6{ #
return query.list(); Gu*y7I8
} 2L~Vr4eHG
{6v.(Zlh$
} TQT3]h6
bO\++zOF
^x\VMd3*w
P+o"]/7U
G0UaE1n
至此,一个完整的分页程序完成。前台的只需要调用 {P8d^=#q
4{YA['
userManager.listUser(page)即可得到一个Page对象和结果集对象 lH4Nbluc^
x(TF4W=j
的综合体,而传入的参数page对象则可以由前台传入,如果用 ks0Q+YW
?Fl}@EA#M
webwork,甚至可以直接在配置文件中指定。 n?fy@R
R%WY!I8C
下面给出一个webwork调用示例: fWmc$r5n](
java代码: ,2fi`9=\
]ZcivnN#
x
vs=T
/*Created on 2005-6-17*/ .jCGtR )%
package com.adt.action.user; X[o+Y@bc
!0,q[|m
import java.util.List; Wlhh0uy
9r].rzf9
import org.apache.commons.logging.Log; fEZuv?@
import org.apache.commons.logging.LogFactory; >J7slDRo
import org.flyware.util.page.Page; FMVAXOO
lV$JCNe
import com.adt.bo.Result; =HCEUB9Fs
import com.adt.service.UserService; B-MS@<2
import com.opensymphony.xwork.Action; JD$g%hcVZa
YGo?%.X
/** 4u:SE
* @author Joa }gkLO
TJ/,
*/ tn5%zJ#+
publicclass ListUser implementsAction{ $xWwI(SaB
eL}w{Hlk
T
privatestaticfinal Log logger = LogFactory.getLog CT[9=wV)m%
r tuaU=U
(ListUser.class); y(J~:"}7)
^/"}_bR
private UserService userService; nqo{]fn
='h2z"}\Bn
private Page page; NfvPE ]S
!q2zuxq!R
privateList users; D.a>i?W
=\O#F88ui
/* GOc
* (non-Javadoc) MT-Tt
* F@u7Oel@m
* @see com.opensymphony.xwork.Action#execute() ]Lub.r
*/ }3{eVct#|
publicString execute()throwsException{ m.K cTM%j
Result result = userService.listUser(page); 9r? Z'~,Za
page = result.getPage(); bTum|GWf
users = result.getContent(); #dZs[R7h
return SUCCESS; 1C<cwd;9
} CeYhn\m5K0
4-yK!LR
/** CVfV
* @return Returns the page. e34>q:#5l
*/ :0r,.)
public Page getPage(){ e=0]8l>\V
return page; %y RGN
} XRV]u|w=g
^p3GT6
/** E8!`d}\#
* @return Returns the users. v)+g<!
*/ h$02#(RHJ
publicList getUsers(){ ~&<#H+O
return users; 4CM'I~
} %hVR|K|J
h!w::cV
/** 8}0wSVsxV$
* @param page 17s~mqy
* The page to set. 1@|+l!rYF
*/ JXc.?{LL
publicvoid setPage(Page page){ (GC]=
this.page = page; UY(T>4H+h
} @"7S$@cO
bT,_=7F
/** ?\o~P
* @param users Xq 135/d
* The users to set. cwmS4^zt8
*/ ME)Tx3d
publicvoid setUsers(List users){ qfDG.Zee#
this.users = users; Af _4Z]F
} 4mvR]:G
E.K^v/dNdq
/** joe)b
* @param userService d/; tq
* The userService to set. h1_Z&VJ
*/ }-oba_
publicvoid setUserService(UserService userService){ \|,| )
this.userService = userService; yx]9rD1cz
} P{o)Ir8Tt
} ^QS`H@+Z
]X6<yzu&+l
w/6X9d
{'IO
11oNlgY&
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, kOydh(yE
r07u6OA
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 DB|1Sqjsn
7a"06Et^
么只需要: PeJ#9hI~rQ
java代码: njs:
dxX`\{E
]rv\sD`[
<?xml version="1.0"?> !6(3Y
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork qZd*'ki<
`Z;Z^c
1.0//EN" "http://www.opensymphony.com/xwork/xwork- '[#y|
u9"=t
1.0.dtd">
|3]/CrR_
~Zr}QO}G
<xwork> O*~,L6# }
&ksuk9M
<package name="user" extends="webwork- Pe@#6N`
Y9^l|,bm5
interceptors"> kE:[6reG
a}yb~:TC
<!-- The default interceptor stack name e0P[,e*0
q/b+V)V
--> IhNX~Jg'^
<default-interceptor-ref 5MnP6(3$
l 2Sar1~1
name="myDefaultWebStack"/> vD#U+
(=!At)O
<action name="listUser" {[!<yUJ`S#
,`HweIq(
class="com.adt.action.user.ListUser"> R #wZW&N
<param ,j_js8r
E;a,].
name="page.everyPage">10</param> T~E;@weR
<result z x-[@G
j}u L
name="success">/user/user_list.jsp</result> I-R7+o
</action> -qP)L;n
<e UsMo<
</package> H7+"BWc
]yPK}u
</xwork> L3%frIUd
ogFo/TKM
ia5%
vqeH<$WHvy
*p(_="J,
$}&a*c>
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 c]M+|R5
U"r*kO%
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。 _WZx].|A=
g7zl5^o3j
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 $]DuO1H./
6\7c:
t<v.rb
:`N&BV
TanWCt4r
我写的一个用于分页的类,用了泛型了,hoho hQ|mow@Zmz
5k0iVpjQ
java代码: _m9k2[N!
"B3jq^
AY52j
package com.intokr.util; IS]A<}j/-
SMZ*30i
import java.util.List; p :xyy*I
2PQBUq
/** '/I`dj
* 用于分页的类<br> ')q0VaohC
* 可以用于传递查询的结果也可以用于传送查询的参数<br> NZ1B#PG,c
* {bXN[=j
* @version 0.01 *ak0(yLn)
* @author cheng T~xVHk1
*/ (u 7Lh>6%
public class Paginator<E> { 6y^
zC?
privateint count = 0; // 总记录数 \Eh5g/,[
privateint p = 1; // 页编号 Zv
%>m
privateint num = 20; // 每页的记录数 LaJvPOQ
privateList<E> results = null; // 结果 J&aN6 l?
$]|3^(y``
/** gCghWg{S
* 结果总数 ]H/,Q6Q
*/ pb97S^K[
publicint getCount(){ UCVYO.
9"
return count; )xcjQkb
} VZqCFE3
:<aGZ\R5
publicvoid setCount(int count){ !}6'vq
this.count = count; gfggL&t(
} V(TtOuv
I">">
/** .!4'Y}
* 本结果所在的页码,从1开始 hF-QbO
* KiXfR\S~C
* @return Returns the pageNo. 8[@,i|kgg0
*/ +'m9b7+v
publicint getP(){ zLl-{Kk
return p; }5fd:B m;
} FsqH:I4O
5X^\AW
/** X4o#kW
* if(p<=0) p=1 NV./p`k
* (A?>U_@
* @param p YW7w>}aW
*/ %f;v$rsZ
publicvoid setP(int p){ RJ?)O#}
if(p <= 0) "[
S[vkI
p = 1; x;W!sO@$
this.p = p; qXtC7uNj$
} cpk\;1&t
=Z.0-C>W
/** Sd6O?&(
* 每页记录数量 7Q!ksp
*/ [7><^?t
V
publicint getNum(){ diXWm-ZKL
return num; #f(a,,Uu'
} .M:&Aj)x16
(7X
/** QI[WXxp
* if(num<1) num=1 uT]$R
*/ _EMXx4J
publicvoid setNum(int num){ ?Q_ @@)
if(num < 1) q# j[0,^ $
num = 1; ?sHZeWZ(
this.num = num; g}`g>&l5
} "vk]y
gbMA-r:IC
/** Vn_&q6Pa
* 获得总页数 f8-`bb
*/ #_ulmB;
publicint getPageNum(){ Ho(MO!(
return(count - 1) / num + 1; 5"h4XINZ
} pq0Z<b;2
iU+SXsXLR4
/** ir'<H<t2
* 获得本页的开始编号,为 (p-1)*num+1 MZ%J
]Nd
*/ 1R_@C.I
publicint getStart(){ w&IYCYK_
return(p - 1) * num + 1; P:g!~&Q
} \:h7,[e
&</)k|.A6\
/** =H7p&DhD