Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 )V%xbDd S
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 f@T/^|`mh
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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 k!b\qS~Q
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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 <ZxxlJS)6
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分页支持类: |\%[e@u
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java代码: E!&A[TlX\
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package com.javaeye.common.util; fDhV
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import java.util.List; lcHwKd
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publicclass PaginationSupport { u;p{&\(]
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publicfinalstaticint PAGESIZE = 30; fi^I1*S
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privateint pageSize = PAGESIZE; <61T)7
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privateList items;
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privateint totalCount; 9{@[l!]W
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privateint[] indexes = newint[0]; J^8(h R
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privateint startIndex = 0; nfET;:{
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public PaginationSupport(List items, int AM cHR=/
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totalCount){ !|;^
setPageSize(PAGESIZE); a|rN %hA4
setTotalCount(totalCount); YyEW}2
setItems(items); EjW3_ %
setStartIndex(0); ["Mq
} L)W1bW}
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public PaginationSupport(List items, int ^F2OTz4n
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totalCount, int startIndex){ ?,uTH
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setPageSize(PAGESIZE); @zo}#.g
setTotalCount(totalCount); 07 [%RG
setItems(items); |^9+c2
setStartIndex(startIndex); BK`NPC$a
} A2>rS
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public PaginationSupport(List items, int X^;[X~g
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totalCount, int pageSize, int startIndex){ FN jT?*
setPageSize(pageSize); @a-u_|3q
setTotalCount(totalCount); =OY&;d!C
setItems(items); ;^+#
setStartIndex(startIndex); 8axz`2 `
} 7{F(NJUO1
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publicList getItems(){ n[DQ5l
return items; XRoMD6qf;
} #=@H-ZuD7
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publicvoid setItems(List items){ M]9oSi
this.items = items; :sO^b*e /
} $7M/rF;N5X
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publicint getPageSize(){ nADt8
return pageSize; =2+';Xk\
} DXX(q k)6
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publicvoid setPageSize(int pageSize){ Arvxl(R\4
this.pageSize = pageSize; p }p1>-j
} "mT95x\NA\
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publicint getTotalCount(){ (EZ34,k'S
return totalCount; 2hB';Dv
} 5vxKkk&i4l
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publicvoid setTotalCount(int totalCount){ <eWGvIEP[
if(totalCount > 0){ "F_o%!l
this.totalCount = totalCount; |GmV1hN
int count = totalCount / }mGOEG|F2
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pageSize; bpe8
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if(totalCount % pageSize > 0) Cjvgf.>$
count++; "= H.$
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indexes = newint[count]; -Vj'QqZ
for(int i = 0; i < count; i++){ t<`h(RczHI
indexes = pageSize * Znl&.,c)
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i; 4Uz:zB
} ^v3+w"2
}else{ vg5zsR0u
this.totalCount = 0;
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} @"9y\1u
} MW9B
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publicint[] getIndexes(){ \3q{E",\>@
return indexes; :Puv8[1i
} Rn{q/h
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publicvoid setIndexes(int[] indexes){ %9mCgHQ9
this.indexes = indexes; HZQ I |
} ,|I\{J #C
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publicint getStartIndex(){ ~E^EF{h
return startIndex; if5Y!Tx?G
} G%YD2<V
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publicvoid setStartIndex(int startIndex){ UO"8 I2rB
if(totalCount <= 0) mC~W/KReA
this.startIndex = 0; ~Y)Au?d(a
elseif(startIndex >= totalCount) 3|:uIoR{
this.startIndex = indexes 5, Yk5?l<'
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[indexes.length - 1]; 54F([w
elseif(startIndex < 0) ^e>v{AE%
this.startIndex = 0; &s/aJgJhp
else{ -I=}SZ
this.startIndex = indexes ]^
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[startIndex / pageSize]; d+T]EpQJ*
} NkO$
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} n^Z?u9VR
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publicint getNextIndex(){ 66L*6O4
int nextIndex = getStartIndex() + @oRYQ|.R
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pageSize; A v2 _A
if(nextIndex >= totalCount) He!0&B\7h
return getStartIndex(); Kg](kP
else
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return nextIndex; .j&jf^a5
} #-lk=>
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publicint getPreviousIndex(){ Mx r#
int previousIndex = getStartIndex() - Y6N+,FAk+J
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pageSize; :&:>sd(QD
if(previousIndex < 0) V)(pe #P
return0; ]`4QJ;#
else ptDA))7M/
return previousIndex; 2! 6Kzq
} O3BU.X1'%
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} }bnkTC
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抽象业务类
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java代码: X1'Ze,34
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/** cXCczqabv
* Created on 2005-7-12 L"-&B$B:
*/ '#Fh
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package com.javaeye.common.business; CKR9APkv
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import java.io.Serializable; *oWzH_
import java.util.List; {r}}X@|5
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import org.hibernate.Criteria; "nefRz%j+
import org.hibernate.HibernateException; 5(|ud)v
import org.hibernate.Session; e/3hb)#;
import org.hibernate.criterion.DetachedCriteria; :)yM9^<D
import org.hibernate.criterion.Projections; 0q;] ;m
import {2Ibd i
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org.springframework.orm.hibernate3.HibernateCallback; ,5?MRqCM
import m{yON&y
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org.springframework.orm.hibernate3.support.HibernateDaoS NEH$&%OV?
=w8 YZs8w
upport; =>J#_Pprn
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import com.javaeye.common.util.PaginationSupport; zVa+5\Q
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public abstract class AbstractManager extends OR9){qP
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HibernateDaoSupport { ;CZcY] ol
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privateboolean cacheQueries = false; (Vv]:Y]
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privateString queryCacheRegion; QMY4%uyY!
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publicvoid setCacheQueries(boolean p'4P2
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cacheQueries){ `ahXn
this.cacheQueries = cacheQueries; VLN3x.BY
} tK
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publicvoid setQueryCacheRegion(String +bnw,B><
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queryCacheRegion){ NZ5~\k
this.queryCacheRegion = mK-:laIL"
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queryCacheRegion; <k6xScy$}
} U;@jl?jnG
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publicvoid save(finalObject entity){ ^ym{DSx
getHibernateTemplate().save(entity); 4vS!99v)
} Se8y-AL6x>
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publicvoid persist(finalObject entity){ tW>R 16zq
getHibernateTemplate().save(entity); | hM)e*"
} PEIr-qs%D
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publicvoid update(finalObject entity){ gj^]}6-P
getHibernateTemplate().update(entity); |GQ$UB
} w"i Zn
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publicvoid delete(finalObject entity){ u_8 22Z
getHibernateTemplate().delete(entity); Wp3l>:
} ;hJ*u
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publicObject load(finalClass entity, VAE?={-
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finalSerializable id){ )du{ZWr
return getHibernateTemplate().load qL.Y_,[[
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(entity, id); !
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} neFno5d j
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publicObject get(finalClass entity, b'5pQ2Mq
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finalSerializable id){ EsB'nf r
return getHibernateTemplate().get RsfTUb)<
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(entity, id); g GT,PP(k
} m(:qZW
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publicList findAll(finalClass entity){ WC*:\:mh
return getHibernateTemplate().find("from D D;+& fe
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" + entity.getName()); t>@3RBEK
} =e-aZ0P
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publicList findByNamedQuery(finalString HCkqh4
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namedQuery){ aEdJ ri
return getHibernateTemplate E(+wl
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().findByNamedQuery(namedQuery); Nw&}qSN
} |Umfq:W`y_
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publicList findByNamedQuery(finalString query, V?dK *8s
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finalObject parameter){ ixHZX<6zYT
return getHibernateTemplate '=G
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().findByNamedQuery(query, parameter); i3&B%JiLX
} cBR8HkP~
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publicList findByNamedQuery(finalString query, Bp{`%86SE
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finalObject[] parameters){ y{I[}$k
return getHibernateTemplate %<#3_}"T|
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().findByNamedQuery(query, parameters); lrX0c$)
} ~G:2iSi(#
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publicList find(finalString query){ N?{1'=Om
return getHibernateTemplate().find 8Y~=\(5>
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(query); {r2|fgi
} _ u|FJTk
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publicList find(finalString query, finalObject UK_aqB
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parameter){ j484b2uj1
return getHibernateTemplate().find \pD=Lv9
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(query, parameter); ZIL|
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} LSu^#B
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public PaginationSupport findPageByCriteria P9TBQW2G{
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(final DetachedCriteria detachedCriteria){ zP h\3B
return findPageByCriteria Xz.Y-5)
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); %::deV7
} YyJ{
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public PaginationSupport findPageByCriteria !MJe+.
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(final DetachedCriteria detachedCriteria, finalint )x8;.@U
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startIndex){ uQu/(5
return findPageByCriteria @6
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(detachedCriteria, PaginationSupport.PAGESIZE, iA3>X-x
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startIndex); ?cs]#6^
} ,c%K)KuPK.
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public PaginationSupport findPageByCriteria T~o{woq}g
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(final DetachedCriteria detachedCriteria, finalint b WbXh$
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pageSize, ?)'
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finalint startIndex){ { 8f+h
return(PaginationSupport) "\/^/vn?
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getHibernateTemplate().execute(new HibernateCallback(){ ^6aS]t
publicObject doInHibernate 5Z9 ~
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\/*Nf?;
(Session session)throws HibernateException { @ 2!C^}d3F
Criteria criteria = 6
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detachedCriteria.getExecutableCriteria(session); ,{?q^"
int totalCount = `l>93A
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((Integer) criteria.setProjection(Projections.rowCount J ;UBnCg
3ar=1_Ar
()).uniqueResult()).intValue(); 2'wr={>W
criteria.setProjection "F-Y^
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(null); Q !9HA[Ly
List items = &:V@2_6"
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criteria.setFirstResult(startIndex).setMaxResults B(j02<-
1$$37?FE
(pageSize).list(); _i3i HR?
PaginationSupport ps = 9W*.lf
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new PaginationSupport(items, totalCount, pageSize, tTotPPZf}
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startIndex); NJZXs_%>$
return ps; of9q"h
} [}>#YPZ
}, true); zwK
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} +}Xr1fr{jw
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public List findAllByCriteria(final T yU&QXb
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DetachedCriteria detachedCriteria){ NQ?x8h3
return(List) getHibernateTemplate 4d!S#zx
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().execute(new HibernateCallback(){ ]Ap`
publicObject doInHibernate %drJ p6n%
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^
(Session session)throws HibernateException { wGPotPdE2
Criteria criteria = #wr2imG6
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detachedCriteria.getExecutableCriteria(session); Hk,lX r
return criteria.list(); D9~}5
} J"-_{)0lD
}, true); TMK'(6dH
} b\?3--q
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public int getCountByCriteria(final $,TGP+vH
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DetachedCriteria detachedCriteria){ ( :{"C6x
Integer count = (Integer) 80Ag
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)
getHibernateTemplate().execute(new HibernateCallback(){ 2B^~/T<\
publicObject doInHibernate dLZjB(0eO
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(Session session)throws HibernateException { )R~aA#<>
Criteria criteria = +P|2m"UA
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detachedCriteria.getExecutableCriteria(session); > @+#
return /}=a{J
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criteria.setProjection(Projections.rowCount 40 2x<H
, ;%yf?
()).uniqueResult(); #4><r.v3
} qIh #~
}, true); g` [` P@
return count.intValue(); ^;r+W-MQ
} |g<* Rk0
} FQROK4x%"
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用户在web层构造查询条件detachedCriteria,和可选的 EY=FDl V
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 *tc{vtuu~^
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PaginationSupport的实例ps。 ZY cd.? :6
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ps.getItems()得到已分页好的结果集 s]H^wrg&
ps.getIndexes()得到分页索引的数组 YTQps&mD.
ps.getTotalCount()得到总结果数 fxgU~'
ps.getStartIndex()当前分页索引 B[F-gq-
ps.getNextIndex()下一页索引 ,PECYwegkt
ps.getPreviousIndex()上一页索引 Gr: 3{o`
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 {q3:Z{#>7
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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 }gGkV]
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一下代码重构了。 0 [8=c&F
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我把原本我的做法也提供出来供大家讨论吧: ]]BOk
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首先,为了实现分页查询,我封装了一个Page类: j U[
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java代码: r-IT(DzkD
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/*Created on 2005-4-14*/ }]+xFj9[>
package org.flyware.util.page; yGj.)$1},@
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/** W^\d^)
* @author Joa `t(D!
* +fNvNbtA
*/ ?LaUed'
publicclass Page { @Uo6>-WF
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/** imply if the page has previous page */ L]d-33.c!H
privateboolean hasPrePage; bZ 443SG
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/** imply if the page has next page */ _S@aGw
privateboolean hasNextPage; |Au ]1}
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/** the number of every page */ \or G63T:
privateint everyPage; .*YD&(
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/** the total page number */ jS<_ )
privateint totalPage; )92r{%N
o[1ylzk}+
/** the number of current page */ 8K"+,s(%R
privateint currentPage; bKDA!R2
][;G=oCT
/** the begin index of the records by the current Kw5Lhc1V
}{[mrG
query */ 7KjUW\mN2Z
privateint beginIndex; hBU\'.x
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/** The default constructor */ ]; Wx
public Page(){ o<i,*y88
x@>&IBiL
} 51BlM%
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/** construct the page by everyPage "v-(g9(
* @param everyPage !j:`7PT\
* */ ^W?Z
public Page(int everyPage){ h8e757z
this.everyPage = everyPage; w5=tlb
} od' /%
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/** The whole constructor */ 1O/
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public Page(boolean hasPrePage, boolean hasNextPage, t.Nb?/
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int everyPage, int totalPage, R&f^+0%f
int currentPage, int beginIndex){ E:`v+S_h
this.hasPrePage = hasPrePage; %@"!8Y(j
this.hasNextPage = hasNextPage; Ro(Zmk\t
this.everyPage = everyPage; (la[KqqCO
this.totalPage = totalPage; U_G gCI)
this.currentPage = currentPage; eLD|A=X?
this.beginIndex = beginIndex; KhbYr$
} q.YfC
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/** x#.C4O09
* @return V5F%_,No
* Returns the beginIndex. UBv@+\Y8m
*/ v
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publicint getBeginIndex(){ @%ip7Y]e
return beginIndex; \!]hU%Un
} kX`[Y@nUN
j=?'4sF
/** SMH<'F7i
* @param beginIndex 2{Vcb
* The beginIndex to set. M$4[)6Y
*/ }Z-Z|G)#
publicvoid setBeginIndex(int beginIndex){ <
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this.beginIndex = beginIndex; X1{[}!
} B~
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%V9ZyQg%*
/** ?S$i?\Qh
* @return l:#-d.z#
* Returns the currentPage. XQ%4L-rhN
*/ YKmsQ(q`N
publicint getCurrentPage(){ %WTEv?I{Ga
return currentPage; d[p;T\?"
} L|-98]8>
SP* fv`
/** v3d&*I
* @param currentPage ".^VI2T
* The currentPage to set.
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*/ b$%0.s
publicvoid setCurrentPage(int currentPage){ x<Vm5j
this.currentPage = currentPage; 2d%}- nw
} k3?rp`V1
;W>Cqg=
/** c~QS9)=E
* @return =OIw*L8C"I
* Returns the everyPage. Wq*b~Lw
*/ D:^$4}h
f
publicint getEveryPage(){ WrPUd{QM
return everyPage; WQyLf;!Lz
} wNFz*|n
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/** g~V+4+
* @param everyPage qd3Q}Lk
* The everyPage to set. h$eEn l}
*/ d8-A*W[
publicvoid setEveryPage(int everyPage){ F
this.everyPage = everyPage; WE]e
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} BH]Yn u&o
akw,P$i
/** bVP"(H]
* @return STZPYeXE
* Returns the hasNextPage. _@S`5;4x
*/ xGTP;NT_H
publicboolean getHasNextPage(){ ljl^ GFo
return hasNextPage; @36u8pE
} z[`@}}Q
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/** ;XM{o:1Y[
* @param hasNextPage F}Vr:~
* The hasNextPage to set. 2'=T[<nNB
*/ ifN64`AhRX
publicvoid setHasNextPage(boolean hasNextPage){ uqz]J$
this.hasNextPage = hasNextPage; }D+}DPL{^
} X7k.zlH7T
iq(
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/** `al<(FwGE
* @return >pUtwIP
* Returns the hasPrePage. *m?/O}R
*/ bfo["
publicboolean getHasPrePage(){ lHgs;>U$
return hasPrePage; Xpzfm7CB/
} cGjPxG;
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/** 9tF9T\jW
* @param hasPrePage H"A7Zo
* The hasPrePage to set. %|s+jeUDn|
*/ (vT+IZEI
publicvoid setHasPrePage(boolean hasPrePage){
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this.hasPrePage = hasPrePage; boDt`2=
} }&_/PA0j
MEB it
/** RX/hz|
* @return Returns the totalPage. vWAL^?HUP
* I`NjqyTW
*/ #g6.Glz3
publicint getTotalPage(){ U&O:
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return totalPage; e7wSOs
} P.gb1$7<
'7O3/GDK
/** Gea\,{E9xA
* @param totalPage N7e"@Ic
* The totalPage to set. #%DE;
*/ ):iA\A5q[
publicvoid setTotalPage(int totalPage){ -GxaV #{
this.totalPage = totalPage; B}^w_C2
} Hh+ 2mkg
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} c/sC&i;%O
dAuJXGo
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S]+:{9d
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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 =>-Rnc@
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个PageUtil,负责对Page对象进行构造: 'inFKy'H
java代码: )ut&@]
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H
/*Created on 2005-4-14*/ Ofs<EQ
package org.flyware.util.page; $< JaLS
9 AJ(&qY(
import org.apache.commons.logging.Log; <7~'; K
import org.apache.commons.logging.LogFactory; q<M2,YrbAI
nrjE.+v
/** a|X a3E
* @author Joa /'/Xvm3
* $&=S#_HQS
*/ vam;4vyu
publicclass PageUtil { 7' Mm205\
$ ` ""
privatestaticfinal Log logger = LogFactory.getLog Hl,W=2N
*WuID2cOI
(PageUtil.class); zolt$p
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/** 7<*yS310
* Use the origin page to create a new page :=Nz}mUV
* @param page ,y#Kv|R
* @param totalRecords ;=MU';o
* @return *}*FX+px)
*/ Fe4(4
publicstatic Page createPage(Page page, int p>huRp^w
h'{ C[d
totalRecords){ x<ZJb
return createPage(page.getEveryPage(), -Fe?R*-g
#pnI\
page.getCurrentPage(), totalRecords); K|[*t~59
} jW A(C;W
'd9INz.
/** )?anOD[
* the basic page utils not including exception /V'A%2Cl=T
@J/K-.r
handler
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* @param everyPage "]}
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* @param currentPage dl.p\t(1
* @param totalRecords 3ca (i/c
* @return page %WjXg:R
*/ 1n;0?MIZ
publicstatic Page createPage(int everyPage, int ?82xdpg
7fZDsj:
currentPage, int totalRecords){ Wi)_H$KII
everyPage = getEveryPage(everyPage); 9dx/hFA
currentPage = getCurrentPage(currentPage); |Y,b?*UF
int beginIndex = getBeginIndex(everyPage, Hquc
o
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currentPage); m+]K;}.}R
int totalPage = getTotalPage(everyPage, X aMJDa|M
,?^ p(w
totalRecords); vg32y /l]S
boolean hasNextPage = hasNextPage(currentPage, &i6),{QN
u 7>],<
totalPage); ?67Y-\}
boolean hasPrePage = hasPrePage(currentPage); Q' {ML4
n-tgX?1'
returnnew Page(hasPrePage, hasNextPage, k%WTJbuG<)
everyPage, totalPage, +V{kb<P
currentPage, *nkoPVpC
R{SF(g3
beginIndex); nksLWfpG?B
} ;,%fE2c
gCB |DY
privatestaticint getEveryPage(int everyPage){
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return everyPage == 0 ? 10 : everyPage; | ATvS2
} +%h8r5o1
_@
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privatestaticint getCurrentPage(int currentPage){ 286jI7 T
return currentPage == 0 ? 1 : currentPage; pmyXLT
} 2K/4Rf0;
nAsh:6${
privatestaticint getBeginIndex(int everyPage, int <L8'! q}
TNe l/
currentPage){ P@V0Mi),
return(currentPage - 1) * everyPage; 8V`WO6*
} 6d<r= C=
aC8} d
privatestaticint getTotalPage(int everyPage, int C)ERUH2i
0z6R'Kjy A
totalRecords){ KQ% GIz x
int totalPage = 0; dO!
kk"qn
T $ >&[f$6
if(totalRecords % everyPage == 0) ?]_$Dcmx
totalPage = totalRecords / everyPage; iL-(O;n
else vc;$-v$&
totalPage = totalRecords / everyPage + 1 ; KQ!8ks]
)Q&(f/LT
return totalPage; rr],DGg+B]
} 0d)M\lG
IL#"~D?
privatestaticboolean hasPrePage(int currentPage){ wDal5GJp
return currentPage == 1 ? false : true; `ts$(u.w
} k8&;lgO'
k<CJ{u0<
privatestaticboolean hasNextPage(int currentPage, 7rc0yB
&[?\k>
int totalPage){ 'CM|@Zz%
return currentPage == totalPage || totalPage == Tztu}t]N
a/4T>eC
0 ? false : true; '}53f2%gKa
} ?jv/TBZX4
$]/{[@5
N2^=E1|_
} !C':
uP)'FI
_^Ubs>d=*
/L
g)i\R;
g[' ^L+hd
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。 8Z8gRcv{p
2j[=\K]
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 C!<Ou6}!b
H(ARw'M
做法如下: ~D j8z+^
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 'urafE4M
we//|fA<
的信息,和一个结果集List: cJ=6r
:
java代码: $f
<(NM6?
]nn98y+
%D{6[8
/*Created on 2005-6-13*/ i
&nSh ]KK
package com.adt.bo; ]g3JZF-
EU/C@B2*Dl
import java.util.List; C_}]`[
{H>gtpVy
import org.flyware.util.page.Page; mp1@|*Sn
F]O`3e=!
/** Cw3a0u
* @author Joa ?=sDM& '
*/ J/y83@
publicclass Result { O3,jg|,
TQF| a\M'
private Page page; .5_2zat0H
gD@){Ip
private List content; cA?W7D
AofKw
/** SwGx?U
* The default constructor R`qFg/S
*/ Qz1E 2yJ
public Result(){ pI\]6U
super(); ?(1y
} rH Lm\3
&jJL"gq"
/** 6Pl<'3&
* The constructor using fields y'q$|
* AO4U}?
* @param page 1v27;Q<+Q
* @param content k(nW#*N_
*/ `Y$4 H,8L
public Result(Page page, List content){ _1\v
this.page = page; _
]ipajT
this.content = content; D#C~pdp
} $bR~+C
eu-*?]&Di
/** 0Th&iA4
* @return Returns the content. %YscBG
*/ Czu9o;xr
publicList getContent(){ 194)QeoFw
return content; CY5Z{qiX
} )mT<MkP
S9y}
/** v@L;x [Q
* @return Returns the page. U?Zq6_M&
*/ 6<QQ@5_
public Page getPage(){ 4xje$/_d
return page; QZ
} *L^,|
Z@S3ZGe
/** N=}A Z{$
* @param content 83_h J
* The content to set. 013x8!i
*/ #=A)XlZMd
public void setContent(List content){ L L~%f
&_
this.content = content; *])
`z8Ox
} vpr.Hn
qR8Lh( "i
/** FcU SE
* @param page R__OP`!
* The page to set. hL{KRRf>
*/ tS=(}2Q
publicvoid setPage(Page page){ [RhO$c$[\
this.page = page; ea
'D td
} ^}o 2
} ",; H`V
~B?y{
8cIKvHx
Ve; n}mJ?
/
zPO
2. 编写业务逻辑接口,并实现它(UserManager, @qAS*3j
*^ZV8c}
UserManagerImpl) }S-O&Z
java代码: $<EM+oJ|ER
p_%Rt"!
?0SJfh
/*Created on 2005-7-15*/ hHnYtq
package com.adt.service; }19\.z&J
\_f(M|
import net.sf.hibernate.HibernateException; n{mfn*r.
+ye3HGD
import org.flyware.util.page.Page; m;QMQeGz
hz@bW2S.
import com.adt.bo.Result; @*((1(q
8<Av@9 *}
/** <0!):zraS
* @author Joa W/h[A3 `3N
*/ }K|oicpUg
publicinterface UserManager { H* *Xu;/5@
s.C_Zf~3
public Result listUser(Page page)throws &V/MmmT
b8 likP"T
HibernateException; M .mfw#*
D'Q\za
} EaN6^S=
s2'h
-[.[>&`/
u'BaKWPS
4|?;TE5
java代码: `[i r}+S
SwMc
pNo
XwaXdvmK
/*Created on 2005-7-15*/ q(84+{>B
package com.adt.service.impl; fNFY$:4X
&%J08l6
import java.util.List; X'iWJ8
S"H2 7
import net.sf.hibernate.HibernateException;
.?$gpM?i
$=4QO
import org.flyware.util.page.Page; W'M*nR|xo
import org.flyware.util.page.PageUtil; Ysv"
6b}
vdwsJPFbc
import com.adt.bo.Result; a&? :P1$
import com.adt.dao.UserDAO; . $vK&k
import com.adt.exception.ObjectNotFoundException; ZJiG!+-j
import com.adt.service.UserManager; S)@j6(HC4
G4"F+%.
/** 5r^(P
* @author Joa Cw&KVw*
*/ G"A#Q"
publicclass UserManagerImpl implements UserManager { xJ.M;SF4
nBYZ}L q
private UserDAO userDAO; 0</);g}
UkFC~17P
/** ,z=LY5_z)
* @param userDAO The userDAO to set. Qo|\-y-#
*/ tKXIk9e
publicvoid setUserDAO(UserDAO userDAO){ SE*g;Cvg1
this.userDAO = userDAO; j0q&&9/Jj
} 4j^
@wV'
3u0RKLc\
/* (non-Javadoc) r9?Mw06Wc5
* @see com.adt.service.UserManager#listUser EfT=?
h/Y'<:
(org.flyware.util.page.Page) LrpM\}t
*/ scV5P Uq
public Result listUser(Page page)throws 1?l1:}^L
SOIN']L|V[
HibernateException, ObjectNotFoundException { do'GlU oMC
int totalRecords = userDAO.getUserCount(); 'LDQgC*%
if(totalRecords == 0) \s\?l(ooq"
throw new ObjectNotFoundException wUJcmM;
A@#E@;lm
("userNotExist"); k+*u/neh
page = PageUtil.createPage(page, totalRecords); _lq`a\7e
List users = userDAO.getUserByPage(page); Tw<q,O
returnnew Result(page, users); 6_B]MN!(
} ,PDQzJY
MF'JeM;H
} 6ik$B
o)/ 0a
"#g}ve,
<1TAw.
<F'\lA9
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 J<lW<:!3]
JW&gJASGC
询,接下来编写UserDAO的代码: gjlx~.0d
3. UserDAO 和 UserDAOImpl: !5!<C,U
java代码: {{!-Gr
Q+{n-? :
%(Icz?
/*Created on 2005-7-15*/ );YDtGip J
package com.adt.dao; %BQ`MZ
r.U`Kh]K
import java.util.List; Q,Eo mt
|w3M7;~eF
import org.flyware.util.page.Page; gRzxLf`K
19#\+LWA
import net.sf.hibernate.HibernateException; D2O~kNd
3OB"#Ap8<
/** &7s.`
* @author Joa 4skD(au8
*/ %a7$QF]
publicinterface UserDAO extends BaseDAO { e|r`/:M
x?<FJ"8"k
publicList getUserByName(String name)throws MHwIA *R
A@u@ift
HibernateException; N$tGQ@
*n!J=yS
publicint getUserCount()throws HibernateException; NxILRKwO
`d(ThP;g
publicList getUserByPage(Page page)throws Iga024KR
\b>]8Un"
HibernateException; U$UIN#
?q [T
} y1#1Ne_
L"aeG
\{D"
!e
7j{?aza
w!XD/jN
java代码: -Qe'YBy:
Uw:"n]G]D?
}-`4DHgq
/*Created on 2005-7-15*/ nr#|b`J]
package com.adt.dao.impl; u%!@(eKM-
'c~4+o4co
import java.util.List; W%Fv p;\`
moE2G?R
import org.flyware.util.page.Page; !'O@2{?B
C_Wc5{
import net.sf.hibernate.HibernateException; '<uq3?5
import net.sf.hibernate.Query; \)Cl%Em
v` r:=K
import com.adt.dao.UserDAO; #LNED)Vg
e#q}F>/L
/** P2nu;I_&
* @author Joa Yr|4Fl~U
*/ {c0`Um3&>
public class UserDAOImpl extends BaseDAOHibernateImpl 4Po_-4
Ea=P2:3*
implements UserDAO { 2t,zLwBdnJ
," ql5Q4
/* (non-Javadoc) "Rl}VeDY
* @see com.adt.dao.UserDAO#getUserByName K<J9~
DaVa}
(java.lang.String) F:ELPs4"
*/ &c #N)U
publicList getUserByName(String name)throws T]$U""
#A.@i+Zv
HibernateException { `$NP>%J-
String querySentence = "FROM user in class BJ0?kX@
%|4UsWZ
com.adt.po.User WHERE user.name=:name"; y+q5UC|
Query query = getSession().createQuery WEpoBP
CL
bPMhfK2 %
(querySentence); )`}:8y?
query.setParameter("name", name); y+;|Fz
return query.list(); R}ecc
} !!y a
.wr>]yN
/* (non-Javadoc) nj4/#W
* @see com.adt.dao.UserDAO#getUserCount() i mM_H;-X
*/ 0CvUc>Pj`"
publicint getUserCount()throws HibernateException { -{A<.a3P}=
int count = 0; J8D,ZfPN`d
String querySentence = "SELECT count(*) FROM o" SMbj
GKCroyor
user in class com.adt.po.User"; 9!tW.pK5
Query query = getSession().createQuery \j.:3Xr
tg/H2p^Y
(querySentence); F1hHe<)
count = ((Integer)query.iterate().next h7@6T+#WoT
g
`4<9RMun
()).intValue(); mVmGg,
return count; jFb?b6b
} mBC+6(5V
YbLW/E\T
/* (non-Javadoc) |nF 8gh~}
* @see com.adt.dao.UserDAO#getUserByPage L=h'Qgk%
,[;G|et
(org.flyware.util.page.Page) H']+L~j
*/ :H[6Lg\*
publicList getUserByPage(Page page)throws z$Qbj
0(btA~'*
HibernateException { SY8C4vb'h
String querySentence = "FROM user in class a: K[ y
CH/rp4NeSy
com.adt.po.User"; t>sE x:
Query query = getSession().createQuery 8$|=P!7EO
)CyS#j#=
(querySentence); F&Hrk|a
query.setFirstResult(page.getBeginIndex()) F<w/PMb
.setMaxResults(page.getEveryPage()); RT5T1K08I
return query.list(); MY/}-*|
} LIdF 0
h1(4Ic
} Np)lIGE
:i7;w%B
]N[ 5q=A5
GH
xp7H
Q7A MRrN
至此,一个完整的分页程序完成。前台的只需要调用 |D.ND%K&
;=UsAB]
userManager.listUser(page)即可得到一个Page对象和结果集对象 &-=5Xc+Z
07 $o;W@
的综合体,而传入的参数page对象则可以由前台传入,如果用 xwty<?dRW1
|)G<,FJQE_
webwork,甚至可以直接在配置文件中指定。 Xry47a
)
RFH0
下面给出一个webwork调用示例: {BHO/q3
java代码: $mB;K]m
PxE3K-S)G
Lh<).<S
/*Created on 2005-6-17*/ [1KuzCcK}
package com.adt.action.user; b u"!jHPB
0|b>I!_"g
import java.util.List; &VcV$8k
]+$?u&0?w
import org.apache.commons.logging.Log; W}1
;Z(.*
import org.apache.commons.logging.LogFactory; Tb-F]lg$
import org.flyware.util.page.Page; .}*"Nv
UY2O Z&&
import com.adt.bo.Result; 2Hv+W-6v
import com.adt.service.UserService; Tac$LS\Q
import com.opensymphony.xwork.Action; m#F`] {
!g.?
/** qjc4.,/
* @author Joa RX5dO%
*/ 8KNZ](Dj
publicclass ListUser implementsAction{ cs'{5!i]
4'Zp-k?5`
privatestaticfinal Log logger = LogFactory.getLog d`6 'Z
V470C@
(ListUser.class); +t;7tQDVB
e~':(/%|5;
private UserService userService; "wHFN>5B
~3 bPIg7D
private Page page; E+JqWR5
V2G6Kw9gt
privateList users; ]$_NyAoBb
1!gbTeVlY
/* '`<w#z}AF
* (non-Javadoc) !v0LBe4
* >dG[G>
* @see com.opensymphony.xwork.Action#execute() N.{D$"
*/ 6MkP |vr6
publicString execute()throwsException{ w+{LAS
Result result = userService.listUser(page); OydwE
page = result.getPage(); O0y_Lm\
users = result.getContent(); veh<R]U
return SUCCESS; m9Hit8f@Q
} *D3/@S$B
""|Qtubv
/** >e"#'K0?\
* @return Returns the page. YUIi;
*/ :08,JL{
public Page getPage(){ }Z,x~G
return page; XvlU*TO~(~
} 8ITdSg
k)Qtfj}uij
/** 680o)hh4m>
* @return Returns the users. :Zz
'1C
*/ \K!VNB>h
publicList getUsers(){ xK\d4"
return users; \;"=QmRD%:
} 9
|vLwQ
\} :PLCKT
/** 5o8EC"
0
* @param page d{7+w/Zi
* The page to set. tC9n
k5~
*/ HoL
Et8Q
publicvoid setPage(Page page){ N'`A?&2ru
this.page = page; 3jC_AO%T
} 7x4PaX(
qm o9G
/** sp*v?5lW
* @param users #?9;uy<j.q
* The users to set. 1PV'?tXp(
*/ \)?HJ
publicvoid setUsers(List users){ "!%l/_p?
this.users = users; %F4%H|G
} `lt"[K<
Gk /fBs
/** A=wh@"2
* @param userService ~O&:C{9=
* The userService to set. .=jay{
*/ %Q dn
publicvoid setUserService(UserService userService){ 7{I0s;R
this.userService = userService; 1^(ad;BCy
} ;x@~A^<el
} "~C,bk
3x'|]Ns
_t #k,;
r
# cGop]
lv+TD!b
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, hNmJ!Uo
*6DB0X_-}
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 8C9-_Ng`
"u^H#L>-q
么只需要: P! #[mio
java代码: zuy4G9P
I75DUJqy]
o="M
<?xml version="1.0"?> -fHy-Oh
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 8&`LYdzt
u frL<]A
1.0//EN" "http://www.opensymphony.com/xwork/xwork- pohp&Tcm
}oGA-Qc}B
1.0.dtd"> ~gZLY ls
Q:k}Jl
<xwork> j yUCH*@
DwE[D]7o
<package name="user" extends="webwork- T!WT;A
AogVF
interceptors"> !\.pq 2
jQ^|3#L\
<!-- The default interceptor stack name R3&Iu=g
wHMX=N1/
--> DjQFi
<default-interceptor-ref
MC.)2B7
ofw3S|F6
name="myDefaultWebStack"/> qm8B8&-
JNXq.;:`Q
<action name="listUser" CSq4x5!_7>
hAnPXiD
class="com.adt.action.user.ListUser">
>rKIG~P_
<param !0L Wa"
=QiI :|eRA
name="page.everyPage">10</param> mQ26K~
<result (b-MMr
c>:wd@w
name="success">/user/user_list.jsp</result> 9} M?P
</action> ?:I* 8Fj
hVAn>_(
</package> NzOx0WLF
=BAW[%1b
</xwork> ryUQU^v
Tc`=f'pP)4
peuZ&yK+"
'UX!*5k<:
[H^z-6x:0
9oR@UW1
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 ^sEYOX\
PB`Y
g
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。 jrr*!^4|
Mhf5bN|wQ
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 &n}f?
O#~yKqB
}1i`6`y1
gANuBWh8T
Rmt~,cW!\
我写的一个用于分页的类,用了泛型了,hoho ][h%UrV
?2{Gn-{
java代码: $f=J2&D,Cz
{xB!EQ"
=I;ZMJR
package com.intokr.util; Tc &z:
zFws:_ i
import java.util.List; oiT[de\S
j2.|ln"!
/** {Y=WW7:Qx
* 用于分页的类<br> ~{B7 k:
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ju8q?Nyhs
* MvHm)h
* @version 0.01 j94=hJVKi
* @author cheng BBRR)
*/ KNpl:g3{<Q
public class Paginator<E> { +LZLy9iKt
privateint count = 0; // 总记录数 uHvp;]/0\
privateint p = 1; // 页编号 lC("y'
::
privateint num = 20; // 每页的记录数 a85$K$b>
privateList<E> results = null; // 结果 xU>WEm2
RD'Q :W
/** #crQ1p) \
* 结果总数 5Y'qaIFR
*/ ~f1%8z
publicint getCount(){ lVR~Bh
return count; T?soJ]A
} E=CsIK
Cc' 37~6~P
publicvoid setCount(int count){
+wvWwie
this.count = count; R_ ,U Mt
} Ug t.&IA
K'Tm_"[u
/** ," Wr"
* 本结果所在的页码,从1开始 I{9QeRI
* >WQMqQ^t@
* @return Returns the pageNo. NI}yVV
*/ st3l2Q
publicint getP(){ EZy)A$|
return p; QP^Cx=
} l7259Ro~
_A5e{Gb
/** (vPN5F
* if(p<=0) p=1 _jI,)sr4ic
* XQs1eP'{
* @param p zRl3KjET
*/ '}JhzKNj
publicvoid setP(int p){ k_qd|
if(p <= 0) qL&[K>2z
p = 1; EC6DW=
this.p = p; DV+xg3\(>1
} ox>^>wR*
+xSHL|:b
/** ^aMg/.j
* 每页记录数量 5uNJx5g
*/ 4 \K7xM!
publicint getNum(){ S)k*?dQ##R
return num; C'+YQ]u
} EXwo,?I
" 4K(jXq|
/** goRL1L,5
* if(num<1) num=1 f/NH:1)y
*/ |`Ntv}
publicvoid setNum(int num){ |`f$tj
if(num < 1) }~jlj
num = 1; 1N^[.=
this.num = num; z8~NZ;A
} \oXpi$
+p_CN*10H
/** I^]2K0+x x
* 获得总页数 yw[g!W
*/ NP#w+Qw
publicint getPageNum(){ /k6MzFoid
return(count - 1) / num + 1; *{@Nq=fE
} c9'vDTE%~
&)Tdc
/** OwUhdiG
* 获得本页的开始编号,为 (p-1)*num+1 5\sd3<:+
*/ +L|?~p`V
publicint getStart(){ /y#f3r+*2
return(p - 1) * num + 1; [f-?ymmT
} mpEK (p
n Fg~< $d
/** !/*\}\'4
* @return Returns the results. r
CHl?J
*/ )!Z*.?
publicList<E> getResults(){ -M~:lK]n
return results; OU(8V^.
} GR.^glG?6
u+e{Mim
public void setResults(List<E> results){ Z{Qu<vy_
this.results = results; Y3cMC)
} hh)`645=x
B6nX$T4zP
public String toString(){ '!cCMTj
StringBuilder buff = new StringBuilder (KD RkE|=
ks qQM
(); 6V:U(g
buff.append("{"); m
3hrb-
buff.append("count:").append(count); ]z;I_-
buff.append(",p:").append(p); qQ/^@3tXL
buff.append(",nump:").append(num); #7$
H
buff.append(",results:").append )VS=E7[
/P3 <"?#k
(results); R)(T^V`{
buff.append("}"); :WS@=sZN
return buff.toString(); B=T'5&
} =/+-<px
j'<<4.(
} D~fl JR
b-?gw64#
sPQQ"|wU