Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 w31Ox1>s
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 "^n,(l*4x
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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 4V')FGB$
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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 'j6O2=1
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分页支持类: tNi>TkC}`
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java代码: l}))vf=i
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package com.javaeye.common.util; .:r~?$(
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import java.util.List; ?BnU0R_r]
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publicclass PaginationSupport { D0r viO
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publicfinalstaticint PAGESIZE = 30; vjuFVJwL
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privateint pageSize = PAGESIZE; j<B9$8x&
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privateList items; hzqJ!
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privateint totalCount; kOYUxr.b
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privateint[] indexes = newint[0]; i+*!"/De
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privateint startIndex = 0; 0ns\:2)cEB
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public PaginationSupport(List items, int dZU#lg
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totalCount){ FE~D:)Xj'?
setPageSize(PAGESIZE); 6p9fq3~7Y
setTotalCount(totalCount); H@Z_P p?
setItems(items); \CL8~
setStartIndex(0); v`HER6
} HZyA\FS
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public PaginationSupport(List items, int >
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totalCount, int startIndex){ 3e_tT8
setPageSize(PAGESIZE); `\kihNkJn3
setTotalCount(totalCount); CL=%eSsuD
setItems(items); l|P"^;*zq
setStartIndex(startIndex); XcVN{6-z
} 53HA6:Q[
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public PaginationSupport(List items, int sT M;l,
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totalCount, int pageSize, int startIndex){ #De>EQ%
setPageSize(pageSize); G;Li!H
setTotalCount(totalCount); `H+"7SO
setItems(items); 2Y
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setStartIndex(startIndex); uU H4vUa
} .H" ?&Mf
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publicList getItems(){ j#l=%H
return items; Eb8pM>'qM
} _f1o!4ocx
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publicvoid setItems(List items){ 8dGsV5" *
this.items = items; !J$r|IX5
} `Ij@;=(
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publicint getPageSize(){ 6_CP?X+T
return pageSize; rq+_[!
} VmS_(bM
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publicvoid setPageSize(int pageSize){ oz)[-
this.pageSize = pageSize; F9K%f&0 a
} ARKM[]
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publicint getTotalCount(){ I'/3_AX
return totalCount; F2"fOS
} #@R0$x
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publicvoid setTotalCount(int totalCount){ >Bt82ibN
if(totalCount > 0){ U0x
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this.totalCount = totalCount; uYh!04u
int count = totalCount / AZj&;!}
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pageSize; Abc{<4 z0?
if(totalCount % pageSize > 0) ['d9sEv .
count++; %w`d
indexes = newint[count]; Un?|RF
for(int i = 0; i < count; i++){
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indexes = pageSize * @\K[WqF$$q
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} As:O|!F
}else{ q+ax]=w
this.totalCount = 0; 70'OS:J=\
} ~ao:9ynY
} ?uWUs )9
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publicint[] getIndexes(){ $0])%
return indexes; 'Y38VOI%
} ZpTDM1ro
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publicvoid setIndexes(int[] indexes){ 7=^{~5#
this.indexes = indexes; F/5&:e?( )
} R9XU 7_3B
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publicint getStartIndex(){ 0vY_
return startIndex; p3s i\Fm!
} c%H' jB[
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publicvoid setStartIndex(int startIndex){ {6i|"5_j
if(totalCount <= 0) `#""JTA"
this.startIndex = 0; u`bD`kfT>
elseif(startIndex >= totalCount) Uh}PB3WZ
this.startIndex = indexes W06aj ~7Z
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[indexes.length - 1]; !_fDL6a-
elseif(startIndex < 0) I)HO/i6>3
this.startIndex = 0; l;-Ml{}|0
else{ HDe\Oty_
this.startIndex = indexes S?~0)EXj(
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[startIndex / pageSize]; a6{Zp{"Y
} 9+ 'i(q
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} *+M#D^qo
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publicint getNextIndex(){ lY%I("2=
int nextIndex = getStartIndex() + ddHl&+G
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pageSize; _w^,j"
if(nextIndex >= totalCount) AuNUW0/
7
return getStartIndex(); E7Lqa
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else !~#zd]0x;
return nextIndex; : auR0FE
} '$ei3
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publicint getPreviousIndex(){ Z.VKG1e}
int previousIndex = getStartIndex() - 0 R6:3fV6R
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pageSize; 4 m:h&^`N
if(previousIndex < 0) (_FU3ZW!
return0; J%"BCbxW~B
else Yy *=@qu>g
return previousIndex; ]#:WL)@
} GJ9>i)+h;
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} Z?)g'n
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抽象业务类 +B*]RL[th
java代码: o1AbB?%=
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/** \n<!
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* Created on 2005-7-12 *HoRYCL
*/ 8dE0y P
package com.javaeye.common.business; s9Hxiw@D
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import java.io.Serializable; fyQOF ItM
import java.util.List; F0$w9p
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import org.hibernate.Criteria; Iz0$T.T
import org.hibernate.HibernateException; aTcz5g0"
import org.hibernate.Session; (/:m*x*6
import org.hibernate.criterion.DetachedCriteria; U,g8:M
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import org.hibernate.criterion.Projections; nPyn~3
import VbX P7bZ
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org.springframework.orm.hibernate3.HibernateCallback; /VYT](
import g p:0 Y
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org.springframework.orm.hibernate3.support.HibernateDaoS h/EIFve
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upport; 9c@M(U@Yh
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import com.javaeye.common.util.PaginationSupport; )Zq'r L<
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public abstract class AbstractManager extends |] 7c&`
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HibernateDaoSupport { oU\]#e^
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privateboolean cacheQueries = false; Z^kE]Ir#EV
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privateString queryCacheRegion; P~a@{n*8
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publicvoid setCacheQueries(boolean <K CI@
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cacheQueries){ a_b#hM/c;
this.cacheQueries = cacheQueries; aC1z.?!U
} p%DU1+SA
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publicvoid setQueryCacheRegion(String }#ink4dK:
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queryCacheRegion){ [Hh*lKg
this.queryCacheRegion = !)bZ.1o
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queryCacheRegion; gTj,I=3$?e
} a2P)@R
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publicvoid save(finalObject entity){ _r:Fmn_%-
getHibernateTemplate().save(entity); }m+Q(2
} o;@~uU
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publicvoid persist(finalObject entity){ cN@_5
getHibernateTemplate().save(entity); 6{6hz8
} ;"M6}5dQ4
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publicvoid update(finalObject entity){ \ ca<L
getHibernateTemplate().update(entity); iq' PeVo
} lC($@sC %
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publicvoid delete(finalObject entity){ g+B7~Z5,
getHibernateTemplate().delete(entity); r^5%0_F]
} ei-\t
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publicObject load(finalClass entity, UF-&L:s[
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finalSerializable id){ ==Egy:<:Q
return getHibernateTemplate().load Y"lEMY
@ T^FOTW
(entity, id); LG8h@HY&L
} Jg$<2CR&
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publicObject get(finalClass entity, u\ _yjv#
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finalSerializable id){ z)M#9oAM
return getHibernateTemplate().get NVRzthg%c_
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(entity, id); Mp/l*"(
} j""ZFh04
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publicList findAll(finalClass entity){ H=@KlSC^
return getHibernateTemplate().find("from lpXGsKH2
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" + entity.getName()); V8/4:Va7s
} uE.BB#
)
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publicList findByNamedQuery(finalString 1)k+v17]f5
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namedQuery){ S]fu
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return getHibernateTemplate {dZ]+2Z~+
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().findByNamedQuery(namedQuery); J$}]p
} _tHhS@
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publicList findByNamedQuery(finalString query, SVo ?o|<
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finalObject parameter){ P<IDb%W
return getHibernateTemplate %M`48TW)
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().findByNamedQuery(query, parameter); &%rM|
} #][i!9$
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publicList findByNamedQuery(finalString query, wW\[#Ku
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finalObject[] parameters){ y@!M<#SEzG
return getHibernateTemplate jRjeL'"G
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().findByNamedQuery(query, parameters); >OaD7
} ,gw9R9 x_
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publicList find(finalString query){ e' M&Eh
return getHibernateTemplate().find cCZp6^/<x
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(query); |OJWQU![by
} 8;?4rrS
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publicList find(finalString query, finalObject #DgHF*GG+>
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parameter){ XHU$&t`7>g
return getHibernateTemplate().find 8GP17j
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(query, parameter); I]C
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} ^:-GPr
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public PaginationSupport findPageByCriteria KFbB}oId
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(final DetachedCriteria detachedCriteria){ ^m%#1Zd
return findPageByCriteria u0L-xC$L
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ol"|?*3q
} y2I7Zd .
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public PaginationSupport findPageByCriteria YJv$,Z&;HO
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(final DetachedCriteria detachedCriteria, finalint Jx5`0?
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startIndex){ VVDN3
return findPageByCriteria upuN$4m&{
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(detachedCriteria, PaginationSupport.PAGESIZE, &MSU<S?1
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startIndex); WrGA7&!+
} 5VV}w R
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public PaginationSupport findPageByCriteria :rL%,o"
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(final DetachedCriteria detachedCriteria, finalint 3Cj)upc
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pageSize, w6s[|i)&
finalint startIndex){ 6&x\!+]F8
return(PaginationSupport) G[mqLI{q
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getHibernateTemplate().execute(new HibernateCallback(){ <(KCiM=E$
publicObject doInHibernate 5e+j51
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(Session session)throws HibernateException { /u$'=!<b;
Criteria criteria = fc+-/!v
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detachedCriteria.getExecutableCriteria(session); 2{h2]F
int totalCount = OV]xo8a;
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((Integer) criteria.setProjection(Projections.rowCount ,4H? + |!
? uYO]!VC
()).uniqueResult()).intValue(); 4"2%mx:
criteria.setProjection VwI
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(null); r)|~Rs!y,
List items = 4fKvB@O@.
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criteria.setFirstResult(startIndex).setMaxResults %k#+nad
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(pageSize).list(); 3 ZOD2:(
PaginationSupport ps = y8$3kXh
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new PaginationSupport(items, totalCount, pageSize, %"f85VfZ
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startIndex); #1%@R<`
return ps; E,m|E]WP
} BHY-fb@R]H
}, true); WVeNO,?ytS
} 4+hNP'e
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public List findAllByCriteria(final ''9]`B,:a0
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DetachedCriteria detachedCriteria){ MQP9^+f)O?
return(List) getHibernateTemplate {O>Td9
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().execute(new HibernateCallback(){ %$ya>0?mq
publicObject doInHibernate $}(Z]z}O ;
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(Session session)throws HibernateException { iOZ9A~Ywy
Criteria criteria = l?)>"^
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detachedCriteria.getExecutableCriteria(session); +~V_^-JG&
return criteria.list(); >IS4
} -dovk?'Gj
}, true); h>bjG
} 9C \}bT
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public int getCountByCriteria(final uM$b/3%s
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DetachedCriteria detachedCriteria){ n*9QSyJN]
Integer count = (Integer) diNSF-wi,,
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getHibernateTemplate().execute(new HibernateCallback(){ zmQQ/7K
publicObject doInHibernate h.?<(I
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(Session session)throws HibernateException { WblH}
Criteria criteria = N_
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detachedCriteria.getExecutableCriteria(session); 0dwD ?GG2
return #!_4ZX
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criteria.setProjection(Projections.rowCount eY`z\I
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()).uniqueResult(); A@~9r9Uf
} O_ r-(wE4
}, true); 7J3A]>qU
return count.intValue(); Srw`vql{(
} cl`kd)"v
} 2.nT k
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用户在web层构造查询条件detachedCriteria,和可选的 W
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 v "2A?
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PaginationSupport的实例ps。 ;ZJ. 7t'
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ps.getItems()得到已分页好的结果集 a:P+HU:
ps.getIndexes()得到分页索引的数组 4NRj>y
ps.getTotalCount()得到总结果数 !gyW15z'
ps.getStartIndex()当前分页索引 -^_^ByJe
ps.getNextIndex()下一页索引 M`7lYw\Or!
ps.getPreviousIndex()上一页索引 }`Wo(E}O
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 l^tRy_T:-
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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 ]/p>p3@1C
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一下代码重构了。 I<W<;A
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我把原本我的做法也提供出来供大家讨论吧: gr!!pp;
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首先,为了实现分页查询,我封装了一个Page类: HXh:83
java代码: 3 q8S
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/*Created on 2005-4-14*/ %Ze7d&
package org.flyware.util.page; 6[FXgCb
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/** {Gh9(0,B?
* @author Joa ( ?e
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* m+dQBsz\
*/ c8zok `\P_
publicclass Page { 25 U+L
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/** imply if the page has previous page */ 4K~>
privateboolean hasPrePage; 2.{zfr
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/** imply if the page has next page */ kTzO4s?
privateboolean hasNextPage; 6 %` h2Z
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/** the number of every page */ CG35\b;Q
privateint everyPage; dBM{]@bZ
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/** the total page number */ +s7w@
privateint totalPage; .f[z_%ar
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/** the number of current page */ c<Ud[x.
privateint currentPage; %<|<%~l&
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/** the begin index of the records by the current ([SJ6ff]&
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query */ +~1FKLu
privateint beginIndex; Y~r)WV!G
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/** The default constructor */ I!lR 7%
public Page(){ 1;,<UHF8N
NTGWI$
} AnE]
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/** construct the page by everyPage }t|i1{%_
* @param everyPage 0=9$k
* */ 6Xn9$C)
public Page(int everyPage){ |~v2~
this.everyPage = everyPage; }Q^*Zq9-
} w}97`.Kt!n
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/** The whole constructor */ y34 <B)Wy
public Page(boolean hasPrePage, boolean hasNextPage, fU.z_T[@
[s]
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int everyPage, int totalPage, 1bDXv,nD
int currentPage, int beginIndex){ VTX6_&Hc1g
this.hasPrePage = hasPrePage; ?5%o-hB|
this.hasNextPage = hasNextPage; XrXW6s;Z
this.everyPage = everyPage; v4X ` Ul*
this.totalPage = totalPage; |WT]s B0Eq
this.currentPage = currentPage; CLuQ=-[|
this.beginIndex = beginIndex; +'VYqu/
} zW`a]n.
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/** SUvrOl
* @return .rX,*|1x
* Returns the beginIndex. .jbxA2
*/ 0q]0+o*%
publicint getBeginIndex(){ @W, <8
return beginIndex; YB:}Lb
} d+
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/** 0xeY0!ux
* @param beginIndex v@J[qpX
* The beginIndex to set. &2ty++gC
*/ )tS;gn
publicvoid setBeginIndex(int beginIndex){ U?5G%o(q
this.beginIndex = beginIndex; *q[;-E(fZ#
} <29K!
[
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/** p3T:Y_
* @return L7.SH#m
* Returns the currentPage. 0fqycGSmU
*/ LEX @hkh
publicint getCurrentPage(){ )NqRu+j
return currentPage; YhqMTOw
} "^a"`?J
%qTIT?6'
/** .aVt d
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* @param currentPage B;W%P.<.
* The currentPage to set. a ~W
*/ 6]kBG?m0
publicvoid setCurrentPage(int currentPage){ FouN}X6
this.currentPage = currentPage; x{tlC}t
} "Aw)0a[j1
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/** g|7o1{
* @return cO5zg<wF
* Returns the everyPage. Ym!e}`A\F
*/ I0z 7bx
publicint getEveryPage(){ \g
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return everyPage; ;ko6igx)+
} PLMC<4$s
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/** evYn}
* @param everyPage i1-%#YYF(
* The everyPage to set. gZ7R^]
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*/ />/e
publicvoid setEveryPage(int everyPage){ o[iN/
this.everyPage = everyPage; ( N};.DB1Y
} js@L%1r#L
;FRUB@:
/** x&0kIF'lq
* @return y$SUYG'v
* Returns the hasNextPage. :zPK
*/ 2zW IB[
publicboolean getHasNextPage(){ s.Ai_D
return hasNextPage; LdN[N^n[H
} PPIO<K 3`
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/** l:uQ#Z)
* @param hasNextPage $T^q>v2u
* The hasNextPage to set. 6w,"i#E!
*/ J{Kw@_ypP
publicvoid setHasNextPage(boolean hasNextPage){ f:<BUqa
this.hasNextPage = hasNextPage; p\lR1
} dIlpo0; F
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/** :Ev
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* @return >RAg63!`
* Returns the hasPrePage. 3IlVSR^py
*/ C49\'1\6
publicboolean getHasPrePage(){ Ez5t)l-
return hasPrePage; ;p`to"6IFD
} 'ET];iZ2
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/** Opc szq5n
* @param hasPrePage 7Y(Dg`8G
* The hasPrePage to set. aaT3-][
*/ A@)Q-V8*9s
publicvoid setHasPrePage(boolean hasPrePage){ (EY@{'.&
this.hasPrePage = hasPrePage; 85q/|9D
} ]Z8u0YtM)
/}8Au$nA
/** Sq ]gU
* @return Returns the totalPage. ~io. TS|r
* k1f<(@*`
*/ wTU$jd1;+
publicint getTotalPage(){ 4=Ru{ewRV
return totalPage; fI<LxU_n:
} ;'8P/a$
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/**
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* @param totalPage v7wyQx+Q
* The totalPage to set. Sl,DZ!
*/ \]]K{DO
publicvoid setTotalPage(int totalPage){ XNJZ~Mowb
this.totalPage = totalPage; nLz;L r!
} klT?h[I!
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} t8EI"|
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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 ?96r7C|
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个PageUtil,负责对Page对象进行构造: K9%rr_ja!
java代码: Za|iU`e\
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/*Created on 2005-4-14*/ pxTtV g.
package org.flyware.util.page; SQ4^sk_!
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import org.apache.commons.logging.Log; FXJ0
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import org.apache.commons.logging.LogFactory; 8fP2qj0
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/** -J+1V{
* @author Joa xn2 nh@;
* |> STb\
*/ `KA==;0
publicclass PageUtil { B.5+!z&7
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privatestaticfinal Log logger = LogFactory.getLog &@oI/i&0B
w gS'/
(PageUtil.class); gPk,nB
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/** p]RQ-0
* Use the origin page to create a new page erEB4q+ #O
* @param page Ip{R'HG/
* @param totalRecords VU,G.eLW
* @return <?7qI8 5OT
*/ 1cOR?=G~
publicstatic Page createPage(Page page, int ,M3hE/rb/
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totalRecords){ Ct)58f2
return createPage(page.getEveryPage(), ({t^/b*8
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page.getCurrentPage(), totalRecords); RQ8d1US
} .yy*[56X
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/** T4.wz
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* the basic page utils not including exception !lNyoX/
c<|y/n
handler 68u?}8}
* @param everyPage X|{T ljn
* @param currentPage rah"\f2
* @param totalRecords iuY,E
* @return page NuR7pjNMZ
*/ ~
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publicstatic Page createPage(int everyPage, int O^~IY/[
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currentPage, int totalRecords){ <K^a2 D
everyPage = getEveryPage(everyPage); _ZhQY,
currentPage = getCurrentPage(currentPage); /";tkad^
int beginIndex = getBeginIndex(everyPage, % vUU
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w~6UOA8}
currentPage); 6a,8t
int totalPage = getTotalPage(everyPage, 5wV J.B~s
8C3oi&av/{
totalRecords); 5m~9Vl-&
boolean hasNextPage = hasNextPage(currentPage, ;"Gy5
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totalPage); `qhT
boolean hasPrePage = hasPrePage(currentPage); $4g{4-)
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returnnew Page(hasPrePage, hasNextPage, Y
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everyPage, totalPage, x[{\Aw>$.
currentPage, aU(.LC
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beginIndex); 6m?<"y8]
} 3*</vo#`
iG54 +]
privatestaticint getEveryPage(int everyPage){ Qg/FFn^Kg*
return everyPage == 0 ? 10 : everyPage; M6p\QKi
} s_y8+BJaV
htbE
Q NW
privatestaticint getCurrentPage(int currentPage){ fPD.np}
return currentPage == 0 ? 1 : currentPage; X,w X)9]J
} W_M#Gi/AL
&qg6^&
privatestaticint getBeginIndex(int everyPage, int P0}B&B/a:
VrRF2(Kn?
currentPage){ +45SKu=
return(currentPage - 1) * everyPage; GV0@We~
} vgy.fP"@
];w}?LFb
privatestaticint getTotalPage(int everyPage, int *S*49Hq7c
)$S=iL8(
totalRecords){ gNW+Dq|X%
int totalPage = 0; ^(:~8 h
PyfWIU7O
if(totalRecords % everyPage == 0) _3 3 b %
totalPage = totalRecords / everyPage; \#%GVru!
else eaf-_#qb
totalPage = totalRecords / everyPage + 1 ; m:)&:Y0 (a
_R ]s1
return totalPage; op`9(=DJ]
} 7k*
y\_+,G0
privatestaticboolean hasPrePage(int currentPage){ NC~?4F[
return currentPage == 1 ? false : true; TQck$&
}
n}a`|Nbk
SN@>m pcJS
privatestaticboolean hasNextPage(int currentPage, 2*75*EQCH
&fB=&jc*j
int totalPage){ .;7V]B1o
return currentPage == totalPage || totalPage == q!Ek
EW\n
8D)1ZUx7`
0 ? false : true; LujLC&S
} :dW\Q&iW
#3*cA!V.<
CsZm8oL$
} &V*MNi,4Z
GwF8ze+cH
)dfhy
j.] ]VA
pZS]i
"
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。 -sA&1n"W&5
3}\ z&|
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 goiI*"6M
C0f%~UMwd
做法如下: 1"CWEL`i
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 X(/fE?%;
w` +,
的信息,和一个结果集List:
VX&g[5zr
java代码: >g !Z|ju
~OX\R"aZBW
a%c <3'
/*Created on 2005-6-13*/ % WDTnEm
package com.adt.bo; H,TApF89A
MuWZf2C
import java.util.List; /#T {0GBXe
424iFc[
import org.flyware.util.page.Page; 3A^AEO
:"#
"{P
/** ~"%'(j_4
* @author Joa !B Pm{_C
*/ `r1j>F7Xb
publicclass Result { <b"^\]l
&Y1h=,KR9
private Page page; 6rbR0dSgx
Fq~Zr;A
private List content; =KQIrS:
%' WC7s
/** mRAt5a#is
* The default constructor cr -5t4<jK
*/ ! xM=7Q
k
public Result(){ !x-__[#
super(); =_=%1rI~
} yg8= G vO
G.O;[(3ab
/** [?N,3
* The constructor using fields j xI;clr
* iC
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* @param page 1 .@{5f3T
* @param content G HQ~{
*/ #tg\
bb
public Result(Page page, List content){ <EqS
,cO^
this.page = page; K?,?.!ev
this.content = content; q1xSylE
} }ACg#;>/+
-cU bIbW
/** T\.~!Q
* @return Returns the content. 3c#^@Bj(-e
*/ [@/p 8I
publicList getContent(){ $yU}56(z~
return content; ;g8v7>p
} *\#<2 QAe
7R[7M%H
/** o% Q7 el$f
* @return Returns the page. R%r25_8
*/ G)YmaHeI;[
public Page getPage(){ ncadVheKt
return page; ;\}dQsX
} E8PwA.
+cXi|Zf
/** ,#BD/dF
* @param content + R6X
* The content to set. :I"22EH
*/ <WWZb\"{
public void setContent(List content){
TR*vZzoy
this.content = content;
}BW&1*M{
} S=S/]]e
o_=4Ex
"
/** ye(av&Hn
* @param page z2Wblh"_
* The page to set. lGK7XAx,
*/ \nyqW4nTm
publicvoid setPage(Page page){ 5h Sd,#:
this.page = page; .nEMd/pX
} @$kzes\
} S=kO9"RB]
H(Wiy@cJn
416}# Mk
s+_8U}R
8[,R4@
2. 编写业务逻辑接口,并实现它(UserManager, D&K9!z"]
Ok)f5")N %
UserManagerImpl) (qR;6l
java代码: ze9n}oN
x ]}'H
' xaPahx;
/*Created on 2005-7-15*/ 8cvSA&l(D
package com.adt.service; tU Je-3,
hFtjw6
import net.sf.hibernate.HibernateException; T1RY1hb|g>
BE&8E\w
import org.flyware.util.page.Page; ^^
SMr l
)@U~Li/+
import com.adt.bo.Result; %AqI'ObC
E0HE@pqr
/** "+ {2!
* @author Joa )gU:Up24|"
*/ GNwFB)?j
publicinterface UserManager { f6SXXkO+
K5bR7f:
public Result listUser(Page page)throws ^wSGrV'
FeZW S>N
HibernateException; "ivVIq2
N`,,sw
} Omn$O>
~#so4<A`3
OhaoLmA}6
HnFH|H<Uf
I)jAdd
java代码: i&m6;>?`
l{?9R.L
QCDica `+*
/*Created on 2005-7-15*/ Je"XIhBr
package com.adt.service.impl; &\5bo=5V
FncP,F$8
import java.util.List; yXtQfR
W:WRG8(F
import net.sf.hibernate.HibernateException; %RwWyzm#\
? YIe<
import org.flyware.util.page.Page; ZF#lh]
import org.flyware.util.page.PageUtil; c;t3I},
)B-[Q#*A-
import com.adt.bo.Result; .2rpQa/h
import com.adt.dao.UserDAO; yO\bVu5V
import com.adt.exception.ObjectNotFoundException; p}I\H
^"8+
import com.adt.service.UserManager; pFu!$.Fr
is%ef
/** 2.@IfBF6
* @author Joa eLHhfu;k
*/ I3Z\]BI
publicclass UserManagerImpl implements UserManager { i-WP#\s
C[ KMaB
private UserDAO userDAO;
BlT)hG(M>
G:|]w,^i
/** gd%Ho8,T
* @param userDAO The userDAO to set. |Q%nnN
*/ ?hp,h3s;n$
publicvoid setUserDAO(UserDAO userDAO){ cj2^wmkB
this.userDAO = userDAO; _\@zq*E
} U? U3?Y-k`
Mxd7X<\$
/* (non-Javadoc) |XQ\c.A
* @see com.adt.service.UserManager#listUser hSps9*y
siV]NI':|
(org.flyware.util.page.Page) gCL}Ba
*/ oj?y_0}:^
public Result listUser(Page page)throws ofYZ!-V
RA+M.
HibernateException, ObjectNotFoundException { gHXvmR"
int totalRecords = userDAO.getUserCount(); lF7".
if(totalRecords == 0) 1Z(9<M1!M
throw new ObjectNotFoundException j39"iAn
931GJA~g
("userNotExist"); ]}&HvrOld
page = PageUtil.createPage(page, totalRecords); Gt,VSpb~s
List users = userDAO.getUserByPage(page); ]_L;AD
returnnew Result(page, users); NSzTl-eS
} m("KLp8
<
jX5}@`z
} O
~[[JAi[
~e]l
Oq}7q!H
-" r4
7^#O{QYol
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 11 A$#\,
9A`^ (
询,接下来编写UserDAO的代码: Z;dR:|%)
3. UserDAO 和 UserDAOImpl: G ,`]2'(@
java代码: C(xsMO'k,,
?ZhBS3L
#rz!d/)Q
/*Created on 2005-7-15*/ ?jbx7')
package com.adt.dao; Iy4REP|
%_39Wa
import java.util.List; :[C|3KKe"
m.5@qmQ
import org.flyware.util.page.Page; B\ZCJaMb
G]Im.x3O-
import net.sf.hibernate.HibernateException; Wrm3U/>e
)2jH&}K
/** (K ]wk9a
* @author Joa f$?`50D"1
*/ &!+1GI9z
publicinterface UserDAO extends BaseDAO { DoN]v
3r?T|>|
publicList getUserByName(String name)throws {uqP+Cs
S[l z>I
HibernateException; p~-)6)We?
szOa yAS
publicint getUserCount()throws HibernateException; ZxCXru1
oy=ej+:
publicList getUserByPage(Page page)throws 7PO]\X^(zE
W=n
Hi\jLV
HibernateException; 9T2y2d!X
x_(K%0+Ca
} zTn.#-7y
ZpwFC7LW
i\K88B&24
w[^lxq
GN+,9
java代码: A`I1G9s
|B2>}Y/
raMtTL+
/*Created on 2005-7-15*/ ,L\KS^>
package com.adt.dao.impl; 6>b#nFVJ
h6:|RGF
import java.util.List; [XP\WG>s
|uJjO>8]|
import org.flyware.util.page.Page; oRmA\R*
[a#*%H{OC
import net.sf.hibernate.HibernateException; :vFYqoCn
import net.sf.hibernate.Query; Ozsvsa
~UwqQD1p
import com.adt.dao.UserDAO; T9>,Mx%D[
2Fbg"de3-
/** "2"2qZ*h}
* @author Joa @~i :8
*/ Ou|kb61zg
public class UserDAOImpl extends BaseDAOHibernateImpl 6x16?x
0.U-
tg0
implements UserDAO { $A98h-*x
8(!?y[
/* (non-Javadoc) &i*e&{L7
* @see com.adt.dao.UserDAO#getUserByName b>& 3XDz
fV!~SX6S
(java.lang.String) YgQb(umK
*/ TO/SiOd
publicList getUserByName(String name)throws aL8Z|*
D@
BP<
HibernateException { \.=,}sV2Z
String querySentence = "FROM user in class w6AG:u
V'l9fj*E
com.adt.po.User WHERE user.name=:name"; Rvj[Csgi
Query query = getSession().createQuery LiEDTXRz
A%EGu4
(querySentence); {w v{"*Q9Q
query.setParameter("name", name); aM\Ph&c7e'
return query.list(); OXV9D:bIa
} jZ<f-Ff0
-]:1zU
/* (non-Javadoc) c:-n0m'i
* @see com.adt.dao.UserDAO#getUserCount() ca'c5*Fs
*/ EB
p(^rj
publicint getUserCount()throws HibernateException { H<l0]-S{
int count = 0; K6nNrd}p:
String querySentence = "SELECT count(*) FROM h-%RSei5
=BeJ.8$@VC
user in class com.adt.po.User"; sGGi7%
Query query = getSession().createQuery 8y]{I^z}
ca:Vdrw`
(querySentence); n?v$C:jLN
count = ((Integer)query.iterate().next Co:Rg@i(F
2bOFH6g
()).intValue(); T?{F7
return count; 0E^S!A7
} oLt%i:, A
V"A*B
/* (non-Javadoc) F^cu!-L
* @see com.adt.dao.UserDAO#getUserByPage `OWwqLoeA
/)V8X#,
(org.flyware.util.page.Page) 8HDI]
*/ Shu=oweJ
publicList getUserByPage(Page page)throws t28 y=nv
wkD"EuW(
HibernateException { }t1J`+x%
String querySentence = "FROM user in class o^x,JT
Nkk+*(Z
com.adt.po.User"; (_Rl
f$D
Query query = getSession().createQuery !PEP`wEKdp
X7)B)r}AG
(querySentence); 1sXVuto
query.setFirstResult(page.getBeginIndex()) lkb,UL;V
.setMaxResults(page.getEveryPage()); 8q|T`ac+N
return query.list(); D|/
4),v
} q]gF[&QZ
%5<Xa
} vk3C&!M<a
+QEiY~i
P A$jR
fQ
bD V/$@p
piAFxS<6
至此,一个完整的分页程序完成。前台的只需要调用
9-Xr
nOU.=N
v`
userManager.listUser(page)即可得到一个Page对象和结果集对象 ;2547b[]
A7aW]
的综合体,而传入的参数page对象则可以由前台传入,如果用 B?;P:!/1
+<sv/gEt
webwork,甚至可以直接在配置文件中指定。 'I@l$H
3d(:Y6D)
下面给出一个webwork调用示例: {\n?IGP?wd
java代码: \!4_m8?
$kY ]HI
F7JF1HfCP
/*Created on 2005-6-17*/ A7zL\U4
package com.adt.action.user; GNM+sdy+
+{s -F g
import java.util.List; h:<?)g~U
.\"8H1I\T
import org.apache.commons.logging.Log; Url8&.pw
import org.apache.commons.logging.LogFactory; _{?-=<V'_
import org.flyware.util.page.Page; _k Utj(re
+y|Q7+
import com.adt.bo.Result; }}zY]A
import com.adt.service.UserService; $u::(s}
x<
import com.opensymphony.xwork.Action; oN=>U"<\1
otdm rw|
/** C]ef
`5NR]
* @author Joa ulNMqz\.
*/ B[;aNyd<
publicclass ListUser implementsAction{ Dn+hI_"#_
dg@'5.ApPu
privatestaticfinal Log logger = LogFactory.getLog VH<-||X/4
;~( yv|f6
(ListUser.class); }EN-WDJD\
;AJ6I*O@+
private UserService userService; 8l
>Xbz
nc.:Wm6Mj
private Page page; G/yYIs
D[3QQT7c
privateList users; +*x9$LSD
uevhW
/* yG,uD!N]|
* (non-Javadoc) 6-f-/$B
* [s~6,wz
* @see com.opensymphony.xwork.Action#execute() 6K5mMu#4
*/ wfQImCZ>l
publicString execute()throwsException{ &|fWtl;43
Result result = userService.listUser(page); xi15B5_Ps
page = result.getPage(); 5GDg_9Bz
users = result.getContent(); yMJ(Sf
return SUCCESS; F?b"Rv
} YGOhUT |
Z~ u3{
/** @81N{tg-
* @return Returns the page. E*d UJ.>
*/ 'm.+ S8
public Page getPage(){ |P7FPmn
return page; %g~zEa-g
} Sn[/'V^$a
@oQ"FLF.
/** (9v%66y
* @return Returns the users. deCi\n
*/ Qn)AS1pL+
publicList getUsers(){ N, 4hh?
return users; =kBN&v_(!
} jt3=<&*Bm
'q1cc5(ueV
/** I8{
mk h
* @param page M[ ON2P;
* The page to set. K7wU
tg
*/ TEi1,yc
publicvoid setPage(Page page){ !HKW_m^3J
this.page = page; @x_0AkZU
} L)"CE].
+6:jm54
/** D_ XOYzN}
* @param users 2W}jbOy
* The users to set. Gyb|{G_
*/ ~"r(PCa@
publicvoid setUsers(List users){ $>rKm
this.users = users; g1~wg$`S8S
} 8LUl@!4b
\w)ddc!ZS
/** p;~oIy\,
* @param userService x;A.Ll
* The userService to set. me$nP}%C&
*/ m|Sf'5fK
publicvoid setUserService(UserService userService){ 2IXtIE
this.userService = userService; n_kE
} L9d|7.b
} A+(+PfU
jOm7:+H
|qpFR)l
D/+l$aBz
$4hi D;n
上面的代码似乎看不出什么地方设置了page的相关初值,事实上,
Ru4M7%
#x \YA#~
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 "G@(Cb*+T
FSYs1Li_C
么只需要: M9?f`9
java代码: fpJ%{z2
0{-?Wy
~U5Tn3'~
<?xml version="1.0"?> ahFK^ #s
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork iqKs:v@+x
/z :1nq
1.0//EN" "http://www.opensymphony.com/xwork/xwork- dF*M"|[
9U Hh#
1.0.dtd"> g!^mewtd
p5l|qs
<xwork> ,h<xY>
[}dPn61
<package name="user" extends="webwork- FcyFE~>2
. Ctd$
interceptors"> z>)lp$
oWEzzMRz
<!-- The default interceptor stack name /#zs
Y$s4 *)%
--> uZ'(fnZ$
<default-interceptor-ref &joP-!"
OxUc,%e9P
name="myDefaultWebStack"/> 5F#FC89Kk
O^@F?CG :1
<action name="listUser" = BbG2k
p!DOc8a.\e
class="com.adt.action.user.ListUser"> ^fmuBe}d{
<param N?O^"
&"7+k5O
name="page.everyPage">10</param> wj5,_d)
<result vOv"^X
^tIYr<I
name="success">/user/user_list.jsp</result> t#w,G
</action> pJuD+v
dA <_`GFR
</package> $F NH:r<
59i2*<k
</xwork> Ctx>#uN6
.9?GKD
q/ (h{cq
N6> rU
5
ed|]LP
u"m TS&
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 kSEgq<i!
ct<XKqbI
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 AQ,"):ofvT
D
!{e
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 t+\<i8
~(B%E'
|;&I$'i
}$g"|;<ha
/:"^,i\t
我写的一个用于分页的类,用了泛型了,hoho 5sNN:m
+ R~!G
java代码: ;aD?BD__Z
Q<KF<K'0hg
$ wDSED -
package com.intokr.util; c6AwO?x/
C|[x],JCS
import java.util.List; W|"bV 6d3
5\h 6'
/** vU(fd!V ?
* 用于分页的类<br> Z4E6J'B8
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 1hzf+*g
* T Qx<lw
* @version 0.01 e)m6xiZ
* @author cheng p<?lF
*/ 2EYWX!Bx
public class Paginator<E> { {fjBa,o
#
privateint count = 0; // 总记录数 MWK)Bn
privateint p = 1; // 页编号 rhZp
privateint num = 20; // 每页的记录数 6/ T/A+u
privateList<E> results = null; // 结果 %LD(S* >7
9c[bhGD?
/** sH'0utD#Y
* 结果总数 lCBH3-0^
*/ e+:X%a4\
publicint getCount(){ |WSpWsr,
return count; ,X;$-.
} _18Z]XtX
rY8(`a
publicvoid setCount(int count){ /I{K_G@
this.count = count; f2&6NC;
} R%q:].
'Yh`B8
/** YB!f =_8
* 本结果所在的页码,从1开始 f.bw A x
* Z9q4W:jyS
* @return Returns the pageNo. =e0MEV#s.
*/ -$Kc"rX
publicint getP(){ c;!|=
return p; U<>@)0~7g!
} hwQ|'^(@O
i_QiE2d
/** "]Uj _d
* if(p<=0) p=1 />pAZa
* <:T/hm$
* @param p F! Cn'*
*/ T 1_B0H2
publicvoid setP(int p){ hl] y):
if(p <= 0) oiC@ /
p = 1; /m,i,NX07
this.p = p; GN=8;Kq%
} ?L H[,8z
r!w*y3
/** cLvnLaA}
* 每页记录数量 _[i.)8$7
*/ U2tgBF?)A
publicint getNum(){ 7/_|/4&
return num; qh&q<M
} g{uiY|
jTZi<
Y:bB
/** #W
l^!)#j?
* if(num<1) num=1 ,fN <I
*/ aY;34SF
publicvoid setNum(int num){ vu}U2 0@
if(num < 1) 1zw,;m n
num = 1; =<)/lz] H
this.num = num; A7&/3C6{H
} JUXBMYFus
Evqy e;
/** 2"j&_$#l5X
* 获得总页数 l-!"
*/ wZbT*rU
publicint getPageNum(){ g\?07@Zd|
return(count - 1) / num + 1; g>eWX*Pa|
} $}5M`p\&C
xDSiTp=)O
/** |nr;OM
* 获得本页的开始编号,为 (p-1)*num+1 J7e/+W~
*/ w@O)b-b|w
publicint getStart(){
"*V'
return(p - 1) * num + 1; &B=z*m
} nD>X?yz2
k`]76C7
/** zlTLp-^Y
* @return Returns the results. N~or.i&a
*/
j0O1??
publicList<E> getResults(){ 9&<c)sS&B
return results; K`ygW|?gt
} ~k?t
G&MO(r}B
public void setResults(List<E> results){ n<HF]
this.results = results; s|Vs#o.P)
} 3[l\l5'm8
S;2UcSsQl
public String toString(){ a9_2b}t
StringBuilder buff = new StringBuilder M195[]
wdV)M?
(); fIatp
buff.append("{"); %u<r_^w5
buff.append("count:").append(count); K;s`
buff.append(",p:").append(p); /k^j'MMQs6
buff.append(",nump:").append(num); RU=g|TL
buff.append(",results:").append K:Z,4Y
?duw0SZ
(results); #q9BU:
buff.append("}"); 5H 1x-b
return buff.toString(); @T.F/Pjhc
} h"}F3E
}v?l0Gk(
} Z3ODZfu>
wLt0Fq6QG
Et}%sdS