Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ?+]
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 JWQd6JQ_~V
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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
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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 ) C#>@W
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分页支持类: oPxh+|0?
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java代码: }F_=.w0
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package com.javaeye.common.util; U@".XIDQ
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import java.util.List; tHJahK:"k
. N5$s2t
publicclass PaginationSupport { YQ-V^e6
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publicfinalstaticint PAGESIZE = 30; *Fd(
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privateint pageSize = PAGESIZE; kc[<5^b5
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privateList items; pQCW6X
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privateint totalCount; T\TKgO=)
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privateint[] indexes = newint[0]; uF@DJX}>
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privateint startIndex = 0; e$-Y>Dd
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public PaginationSupport(List items, int F,xFeq$/{
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totalCount){ ZY)&Fam}
setPageSize(PAGESIZE); )%I62<N,z
setTotalCount(totalCount); 1[(/{CClB
setItems(items); \2[
setStartIndex(0); _W BWFGj
} 0w".o!2\U{
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public PaginationSupport(List items, int Z"9D1Uk
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totalCount, int startIndex){ YZc{\~d
setPageSize(PAGESIZE); 1{CVd m<9
setTotalCount(totalCount); $btk48a 7
setItems(items); P\2x9T
setStartIndex(startIndex); LHusy;<E[
} U1pwk[
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public PaginationSupport(List items, int sWMY
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)#Id=c
totalCount, int pageSize, int startIndex){ _3m\r*(vmQ
setPageSize(pageSize); 'q{d? K
setTotalCount(totalCount); "IzM:
setItems(items); `6Yk-5
setStartIndex(startIndex); z4s{a(Tsd
} iRI7x)^0"z
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publicList getItems(){ 8^qLGUxz
return items; Dp;6CGYl?
} oN.#q$\` k
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publicvoid setItems(List items){ +{&++^(}a
this.items = items; I*=
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} z?g\w6
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publicint getPageSize(){ 9y;8JO
return pageSize; }N#hg>;
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} QzD8
jk#
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publicvoid setPageSize(int pageSize){ q=/ck
this.pageSize = pageSize; O.'\GM
} dQPW9~g8Hg
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publicint getTotalCount(){ @l&>C#K\
return totalCount; w*IDL0#
} X[$FjKZh=F
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publicvoid setTotalCount(int totalCount){ f>ilk Q`
if(totalCount > 0){ 9Z. WR-}
this.totalCount = totalCount; {GQRJ8m
int count = totalCount / %g=SkQ&d
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pageSize; JrwR:_+|
if(totalCount % pageSize > 0) kSU]~x
count++; '>dx~v %
indexes = newint[count]; fqD1Ej
for(int i = 0; i < count; i++){ ??? ;H
indexes = pageSize * +IbQVU~/
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} p7]V1w :
}else{ sEEyN3 N
this.totalCount = 0; z-;{pPZ
} S,^)\=v
} hD>cxo
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publicint[] getIndexes(){ F@kd[>/[
return indexes; VK]sK e
} s92SN F}g
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publicvoid setIndexes(int[] indexes){ +jGSD@32>
this.indexes = indexes; bv4G!21]*;
} W3 2]#M=
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publicint getStartIndex(){ .a]9 rQQ&_
return startIndex; L
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} VgcLG ]tE[
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publicvoid setStartIndex(int startIndex){ {|/y/xYgy'
if(totalCount <= 0) "'*w_H0
this.startIndex = 0; Ggp. %kS6F
elseif(startIndex >= totalCount) q;=! =aRg
this.startIndex = indexes ?bH!|aW(H
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[indexes.length - 1]; \LQ54^eB
elseif(startIndex < 0) _*LgpZ-2(
this.startIndex = 0; W60C$*h
else{ +|TFxaVz
this.startIndex = indexes ;n;bap
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[startIndex / pageSize]; .{
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} @_C?M5v
} p2uZ*sY(D
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publicint getNextIndex(){ y-#01Z
int nextIndex = getStartIndex() + f,'9Bj.~
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pageSize; [mA\,ny9
if(nextIndex >= totalCount) ?Y\hC0a60
return getStartIndex(); -5sKJt]+i
else ,K~r':ht
return nextIndex; S_dM{.!Z(,
} M5T4{^i
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publicint getPreviousIndex(){ rJ)8KY>
int previousIndex = getStartIndex() - OVa38Aucr3
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pageSize; }+ZZO0
if(previousIndex < 0) U@<]>.$
return0; F*j0o
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else Ee 15Y$1
return previousIndex; (bo-JOOdY(
} qB8R4wCf
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}
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抽象业务类 hmM2c15T5
java代码: !pAb+6~T
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/** x4%1P w
* Created on 2005-7-12 PiZU_~A
*/ +jN%w{^=
package com.javaeye.common.business; 5tQZf'pHfd
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import java.io.Serializable; IT=<p60"
import java.util.List; mVNHH!
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import org.hibernate.Criteria; Gx/kel[Y}
import org.hibernate.HibernateException; @z1pE@7jK
import org.hibernate.Session; kYnp$8
import org.hibernate.criterion.DetachedCriteria; y,cz;2
import org.hibernate.criterion.Projections; s?~lMm' !
import )0N^rw kW
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org.springframework.orm.hibernate3.HibernateCallback; W~qVZ(G*U
import \zM3{{mV/
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org.springframework.orm.hibernate3.support.HibernateDaoS W 2T6JFv
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upport; :oO
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import com.javaeye.common.util.PaginationSupport; ['jr+gIfQ
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public abstract class AbstractManager extends ZYo?b"6A
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HibernateDaoSupport { ibn(eu<uW
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privateboolean cacheQueries = false; q!4eVg*
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privateString queryCacheRegion; `|WEzW~
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publicvoid setCacheQueries(boolean L. DD
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cacheQueries){ cT(=pMt8>
this.cacheQueries = cacheQueries; KuJNKuHa.
} :jr`}Z%;y
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publicvoid setQueryCacheRegion(String GvI8W)d3,R
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queryCacheRegion){ >vKOG@I
this.queryCacheRegion = #bwGDF
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queryCacheRegion; o9]i
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} "< })X.t
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publicvoid save(finalObject entity){ CWa~~h<r-
getHibernateTemplate().save(entity); B!1Bg9D
} 7r o&Q%
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publicvoid persist(finalObject entity){ 4=qZ Z>[t
getHibernateTemplate().save(entity); 4~i?xo=;v
} 6<mlx'
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publicvoid update(finalObject entity){ PWk\#dJN&
getHibernateTemplate().update(entity); LDh,!5G-M
} }*?,&9/_)
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publicvoid delete(finalObject entity){ `lA_knS
getHibernateTemplate().delete(entity); ?Sr7c|a2
} >PK 6CR
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publicObject load(finalClass entity, ]\m>N]P]
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finalSerializable id){ Q)Q1a;o
return getHibernateTemplate().load | Pi! UZB
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(entity, id); -CLBf'a
} c<,R,DR
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publicObject get(finalClass entity, XNJ3.w:R
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finalSerializable id){ 6uIgyO*;k
return getHibernateTemplate().get +E-CsNAZ*"
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(entity, id); {"c`k4R
} c8LMvL
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publicList findAll(finalClass entity){ n?*r, )'
return getHibernateTemplate().find("from d9up!
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" + entity.getName()); X& mD/1
} H3LuRGe&2
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publicList findByNamedQuery(finalString L7]o^p{g}Q
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namedQuery){ i>O8q%BnJ
return getHibernateTemplate Xo$SQ0K
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().findByNamedQuery(namedQuery); 83J63Xa
} 28qlp>U
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publicList findByNamedQuery(finalString query, -&l%CR,U
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finalObject parameter){ 0D Lw
return getHibernateTemplate ?j&ZzK'#^
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().findByNamedQuery(query, parameter); Eq|5PE^7
} }N&?8s=
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publicList findByNamedQuery(finalString query, _y&XFdp
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finalObject[] parameters){ f,x;t-o+R
return getHibernateTemplate z*B?Hw),
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().findByNamedQuery(query, parameters); C1>zwU_zo
} 05:?5M4};
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publicList find(finalString query){ ST2:&xH(
return getHibernateTemplate().find OG9 '[o`8
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(query); Lt
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} i+F*vTM2,
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publicList find(finalString query, finalObject >#)%/Ti}DU
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parameter){ yi:}UlO
return getHibernateTemplate().find J/IRCjQ}
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(query, parameter); 1R;@v3
} O>'tag
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public PaginationSupport findPageByCriteria et"Pb_-U
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(final DetachedCriteria detachedCriteria){ xS>vmnW
return findPageByCriteria \d*ts(/a*
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 'iTY?
} #^BttI
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public PaginationSupport findPageByCriteria !9.FI{W
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(final DetachedCriteria detachedCriteria, finalint {,u})U2
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startIndex){ OE}FZCXF
return findPageByCriteria xZ6x`BET-
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(detachedCriteria, PaginationSupport.PAGESIZE, \KzH5 ?
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startIndex); 7377g'jL
} BeN]D
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public PaginationSupport findPageByCriteria DJ*mWi.
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(final DetachedCriteria detachedCriteria, finalint &_u.q/~
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pageSize, bLSc=f&
finalint startIndex){ ^/6P~iK'
return(PaginationSupport) ;rF[y7\
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getHibernateTemplate().execute(new HibernateCallback(){ Oet+$ b
publicObject doInHibernate K7([Gc9
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(Session session)throws HibernateException { ;b:'i&r
Criteria criteria = shw"TF>?zG
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detachedCriteria.getExecutableCriteria(session); :w!hkUx#
int totalCount = 9K#3JyW*
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((Integer) criteria.setProjection(Projections.rowCount TQmrL
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()).uniqueResult()).intValue(); lx=tOfj8
criteria.setProjection ]%y>l j?Y
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(null); 7~F~ 'V
List items = xQ7U$QF|]
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criteria.setFirstResult(startIndex).setMaxResults :o .+<_&
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(pageSize).list(); !><asaB]1
PaginationSupport ps = ;g? |y(xv
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new PaginationSupport(items, totalCount, pageSize, o<%0|n_O&
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startIndex); k=[s%O6H
return ps; 92t.@!m`
} -fl6M-CYX
}, true); bc4 V&
} ]d-.Mw,'
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public List findAllByCriteria(final ! xG*W6IT
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DetachedCriteria detachedCriteria){ PCHspe9!y
return(List) getHibernateTemplate )Z:D}r8[
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().execute(new HibernateCallback(){ /.<v,CR
publicObject doInHibernate Y#XRn_2D
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(Session session)throws HibernateException { gK9d `5
Criteria criteria = !{(Bc8
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detachedCriteria.getExecutableCriteria(session); ^a_a%ws
return criteria.list(); 4k-Ak6s
} BjsT 9?6W/
}, true); qSB&Q0T
} WA"~6U*
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public int getCountByCriteria(final a!E22k?((z
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DetachedCriteria detachedCriteria){ |:&6eDlR
Integer count = (Integer) n\l?+)S *
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getHibernateTemplate().execute(new HibernateCallback(){ nAEyL+6U
publicObject doInHibernate No} U[u.O
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(Session session)throws HibernateException { |Z<\k x
Criteria criteria = n)98NSVDbT
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detachedCriteria.getExecutableCriteria(session); "mf$E|
return DkEv1]6JI_
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criteria.setProjection(Projections.rowCount +q'1P}e
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()).uniqueResult(); NFZ(*v1U
} j*G: 8Lg
}, true); robg1
return count.intValue(); \agZD+
} T5."3i
} 1.F&gP)9
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用户在web层构造查询条件detachedCriteria,和可选的 Td|u@l4B
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 %7)TiT4V
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PaginationSupport的实例ps。 v}6iI}r
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ps.getItems()得到已分页好的结果集 31a,i2Q4
ps.getIndexes()得到分页索引的数组 \X:e9~
ps.getTotalCount()得到总结果数 oT):#,s
ps.getStartIndex()当前分页索引 M}x%'=Pox
ps.getNextIndex()下一页索引 **Ioy+
ps.getPreviousIndex()上一页索引 hr
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 B2ln8NF#Q
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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 6iyl8uL0J
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一下代码重构了。 q`'f
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我把原本我的做法也提供出来供大家讨论吧: M?eP1v:<+G
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首先,为了实现分页查询,我封装了一个Page类: G+8)a$?v
java代码: E+@Q
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/*Created on 2005-4-14*/ O8@65URKx
package org.flyware.util.page; cERIj0~
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/** ?ZlXh51
* @author Joa h9H z6
>
* 4d@yAr}
*/ #c^]p/
publicclass Page { iWf+wC|
Q"XDxa'7"
/** imply if the page has previous page */ cmG27\c RO
privateboolean hasPrePage; |q*yuK/
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/** imply if the page has next page */ 4H-eFs%5
privateboolean hasNextPage; yxt"vm;
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/** the number of every page */ <T}U 3lL^
privateint everyPage; L7C ;l,ot
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/** the total page number */ |u>(~6
privateint totalPage; ?Ij(B}D
Z@0tZ^V{
/** the number of current page */ M*zpl}
privateint currentPage; @s LN
V!He2<
/** the begin index of the records by the current 2LtDS?)@
%} `` :
query */ yW|J`\`^T
privateint beginIndex; ^5sA*%T4
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/** The default constructor */ vhfjZ
public Page(){ ]].~/kC^3k
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} og}Ri!^
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/** construct the page by everyPage >3uNh:|>/
* @param everyPage ,eyh%k*hz
* */ 8_('[89m
public Page(int everyPage){ u9hd%}9Qd?
this.everyPage = everyPage; yJ $6vmQ
} _re# b?
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/** The whole constructor */ c;VqEpsbl
public Page(boolean hasPrePage, boolean hasNextPage, zC2:c"E
I
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int everyPage, int totalPage, =0ZRGp
int currentPage, int beginIndex){ EK';\}
this.hasPrePage = hasPrePage; u<ed O+
this.hasNextPage = hasNextPage; &u>dKf)5
this.everyPage = everyPage; 3a?-UT!
this.totalPage = totalPage; QHR,p/p
this.currentPage = currentPage; [CJ<$R !
this.beginIndex = beginIndex; ^K?-+
} $tmdE)"&
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/** o}rG:rhIh
* @return h9)S&Sk{s
* Returns the beginIndex. -5<[oBL;
*/ |R}=HsYey
publicint getBeginIndex(){ >w
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return beginIndex; k>($[;k|b
} (P|[<Sd
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/** (7Z+ De?
* @param beginIndex U~x]2{}
* The beginIndex to set. DDeU:
*/ T*x2+(r
publicvoid setBeginIndex(int beginIndex){ _,J+b R+b
this.beginIndex = beginIndex; |MwV4^
} I1<WHq
6'# 5Dqw"r
/** TjUwe@&Rw
* @return G}nJ3
* Returns the currentPage. lFzVd
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*/ =1IK"BA2?
publicint getCurrentPage(){ }DhqzKl
return currentPage; ok:uTeJI
} S1QMS
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/** AF'<
* @param currentPage mku@n;Hl_
* The currentPage to set. v;]rFc#Px[
*/ $mQ0w~:@
publicvoid setCurrentPage(int currentPage){ up5f]:!
this.currentPage = currentPage; A=<7*E
} V
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/** |:eTo<
* @return <z<>E1ZLI
* Returns the everyPage. M"3"6U/ e
*/ , PlH|
publicint getEveryPage(){ ,H]%4@]|o
return everyPage; I C
} [HILK`@@
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/** *#=Ij r~
* @param everyPage nR_Zrm
* The everyPage to set. :G _
*/ q'mh*
publicvoid setEveryPage(int everyPage){ #V>R#Oh}
this.everyPage = everyPage; P 9?cp{*
} qf? "v;
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/** Sm'Tz&!
* @return CRb*sfKDL
* Returns the hasNextPage. mnpk9x}m
*/ 8b/$Qp4d
publicboolean getHasNextPage(){ YG\#N+D
return hasNextPage; QEyL/#Q
} 2"ax*MQH<^
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/** _T\ ~%
* @param hasNextPage (nqry[g&
* The hasNextPage to set. *ID=X!v
*/ 8['R D`O
publicvoid setHasNextPage(boolean hasNextPage){ .+:iAnf
this.hasNextPage = hasNextPage; Q#eMwM#~
} T[\1=h]
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/** '`jGr+K,wU
* @return :v^/k]S
* Returns the hasPrePage. D3o,2E(o
*/ > 80{n8
publicboolean getHasPrePage(){ /!5Wd(:
return hasPrePage; ] ?DU8
} m{q'RAw
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/** *'Yy@T8M
* @param hasPrePage R"t#dG]1t
* The hasPrePage to set. .QvD603%5
*/ m+c-"arIpA
publicvoid setHasPrePage(boolean hasPrePage){ uxfh?gsL
this.hasPrePage = hasPrePage; DDrR9}k
} iH(7.?.r
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/** {$frR "K
* @return Returns the totalPage. 2-4N)q
* rq%]CsRY5
*/ zhn?;Fi
publicint getTotalPage(){ /oPW0of
return totalPage; w#.3na
} u&zY>'}zm
5 ^{~xOM5
/** *Soi
* @param totalPage Tz,-~ mc
* The totalPage to set. U)(R4Y6 v
*/ gVG^R02#<k
publicvoid setTotalPage(int totalPage){ -`L`kL<
this.totalPage = totalPage; l(>6Yq
} a{8a[z
"| '~y}v_
} dseI~}
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 r^
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个PageUtil,负责对Page对象进行构造: Z
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java代码: YSnh2 Bq
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/*Created on 2005-4-14*/ Myc-lCE
package org.flyware.util.page; P+CV4;Xz
rNN>tpZ}
import org.apache.commons.logging.Log; 8Ths"zwn
import org.apache.commons.logging.LogFactory; 5:@bNNX'j
?mH=3
:~
/** YmljHQP
* @author Joa !u7KgB<=/F
* 1Yb &E7j
*/ H!;N0",]N
publicclass PageUtil { 'w:ugb9]
7
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privatestaticfinal Log logger = LogFactory.getLog +/B
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(PageUtil.class); T!jh`;D+
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/** 8\{!*?9!
* Use the origin page to create a new page x1:mT[[$
* @param page t24`*'
* @param totalRecords W?Z>g"
* @return 'n|U
*/ FVXsu!R
publicstatic Page createPage(Page page, int P>_O :xD
jIKg* @
totalRecords){ g9C;JmU
return createPage(page.getEveryPage(), czRBuo+k+
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page.getCurrentPage(), totalRecords); hj];a,Br&
} {\>4)TA
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/** ?0~g1"Y-*K
* the basic page utils not including exception !*l /Pr^8
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handler SS/vw%
* @param everyPage JE O$v|X
* @param currentPage *<\`"C;
* @param totalRecords O/eZ1YAC
* @return page wH"9N+82M
*/ (^yaAy#4
publicstatic Page createPage(int everyPage, int ;Am3eJa*-
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currentPage, int totalRecords){ +"84.PZ
everyPage = getEveryPage(everyPage); !w7/G
currentPage = getCurrentPage(currentPage); C).\ J !
int beginIndex = getBeginIndex(everyPage, @Z/jaAjUC
F
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currentPage); 6vNW)1{nn
int totalPage = getTotalPage(everyPage, (H:c80/V
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totalRecords); _sy{rnaqvb
boolean hasNextPage = hasNextPage(currentPage, 4`?PtRX
5 =;cN9M@
totalPage); |ts0j/A]Pi
boolean hasPrePage = hasPrePage(currentPage); r
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3?E7\\/R
returnnew Page(hasPrePage, hasNextPage, B2r[oT R
everyPage, totalPage, +kWWx#L#
currentPage, bofI0f}5.
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beginIndex); <HnJD/g
} O n0!>-b,
`GE8?UO-
privatestaticint getEveryPage(int everyPage){ [w}- )&c
return everyPage == 0 ? 10 : everyPage; sd4eG
} D@p{EH
ET^?>YsA
privatestaticint getCurrentPage(int currentPage){ u""26k51
return currentPage == 0 ? 1 : currentPage; /BgXY}JC.
} 6EC',=)6R
n]6'!Eo
privatestaticint getBeginIndex(int everyPage, int OK4r)
,LZA\XC
currentPage){ v
RD/67
return(currentPage - 1) * everyPage; 38sLyoG=i
} n\;;T1rM
pYcs4f!?p
privatestaticint getTotalPage(int everyPage, int #j7&2L
L%H\|>k`
totalRecords){ MO0t
int totalPage = 0; ((Av3{05H&
4evN^es'I_
if(totalRecords % everyPage == 0) >4@w|7lS
totalPage = totalRecords / everyPage; $mK;{9Z
else <e! TF@
totalPage = totalRecords / everyPage + 1 ; nql1I<I
-f ?
return totalPage; 6,4vs+(|\
} Wpf~Ji6||
a6zWg7 PN
privatestaticboolean hasPrePage(int currentPage){ RQ0^
1
R
return currentPage == 1 ? false : true; A*BN
} b81^756
`[$>S
privatestaticboolean hasNextPage(int currentPage, ty5# a
:Xy51p`.;]
int totalPage){ NcbW"Qv3
return currentPage == totalPage || totalPage == Z>UM gu3c
F
u5zj\0J
0 ? false : true; !hJ!ck]M
} 7/M[T\c
O-.G("
)09ltr0@"
} ?h1g$SBxk
w3i74C&0
2iKteJ@h)
E6R\DM
kJ%a;p`O
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。 4,@jSr|I3i
pj7al;
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 +PBl3
p+ReQ.5|
做法如下: HJb^l 4Q
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 aAP86MHO
s5v}S'uO{
的信息,和一个结果集List: "%Ief4
java代码: w15a~\Qu
J:)ml
HjzAFXRG
/*Created on 2005-6-13*/ qsEFf(9G
package com.adt.bo; k]AL\)
&W
Zk~Pq%u
import java.util.List; 6W:]'L4!
Hxy=J
import org.flyware.util.page.Page; tSni[,4Kq
[c;0eFSi2
/** 63'%+
* @author Joa <iH
*/ L{1[:a)']B
publicclass Result { $ r-rIW5\
djoP`r
private Page page; 'w1ll9O
Zqf
ovG
private List content; F <iV;+
9s!R_R&W.
/** ;dfIzi
* The default constructor \PZ;y=]p}
*/ e34g=]"
public Result(){ pub?%
super(); +BM[@?"hrh
} b7+(g[O
S.>fB7'(?=
/** uMm`j?Y23q
* The constructor using fields (I6Q"&h]
* %p7onwKq0
* @param page Ik,N/[
* @param content 9W-"mD;
*/ i"+TKo-
public Result(Page page, List content){ ve"tbNL
this.page = page; QxbG-B^)=
this.content = content; x8c>2w;6x^
} PYNY1|3
vo:h"ti
/** *6][[)(
* @return Returns the content. <Vt"%C
*/ Myn51pczl
publicList getContent(){ F(/Ka@
return content; X]2x0
} ,*9gy$
zgGJ<=G.
/** YADXXQ"
* @return Returns the page. xEq? [M
*/ GBBp1i
public Page getPage(){ ru/{s3
return page;
KR R)pT
} [ns==gDD
A!^r9 ?<
/** JbitRV@a
* @param content f8UJ3vB
* The content to set. `H9+]TWj<
*/ B@ z ng2[
public void setContent(List content){ a*&&6Fo
this.content = content; tCRsaDK>
} A"qDc
Z<=L
/** ugj I$u
* @param page 2[1t
)EW
* The page to set. uK#2vgT
*/ u] G
publicvoid setPage(Page page){ `SZ-o{
this.page = page; vxi_Y\r=T
} !?J-Y
} 5-H"{29
PQ;9iv
B>I:KGkV
_d^d1Q}V
+BhJske
2. 编写业务逻辑接口,并实现它(UserManager, S{)K_x
<gFisc/#r
UserManagerImpl) &Cm]*$?
java代码: "&`>+Yw
m;1/+qs0
9s7TLT k
/*Created on 2005-7-15*/ N9*QQ0
package com.adt.service; I\M
}Dxpp
(!efaj
import net.sf.hibernate.HibernateException; ;bHS^
QX&Y6CC`]
import org.flyware.util.page.Page; @KHY8y7
o!&+ _BKw
import com.adt.bo.Result; Vo.~1^
z TPNQ0=|
/** rXBCM
* @author Joa +T4}wm
*/ WjSu4
publicinterface UserManager { 9&6P,ts%Q
)J+A2>
public Result listUser(Page page)throws ^ rUq{
#_K<-m%9
HibernateException; <$Sl%DoS
k!bJ&} Q(b
} z;/8R7L&
Bva2f:)K|
B~@Gfb>`'
}L%2K"8?}
9KJ}Ai
java代码: r1}1lJ>7H
Eht8~"fj
>vYb'%02
/*Created on 2005-7-15*/ xsy45az<ip
package com.adt.service.impl; ( *K)D$y
,&fZo9J9
import java.util.List; hM>.xr
,Jn` qvmi
import net.sf.hibernate.HibernateException; 9`"#OQPn1
JBZ1DZAWC
import org.flyware.util.page.Page; tGbx/$Y
import org.flyware.util.page.PageUtil; .yD
6$!6
bC) <K/Q9
import com.adt.bo.Result; 0V^I.S/q
import com.adt.dao.UserDAO; T2tvU*[=
import com.adt.exception.ObjectNotFoundException; {^:NII]
import com.adt.service.UserManager; m~P30)
]$sb<o
.a
/** J6>tGKa+e
* @author Joa kd]CV7(7
*/ 1,]FLsuy
publicclass UserManagerImpl implements UserManager { `CBXz!v!O
Xh3b=i|K
private UserDAO userDAO; \1n (Jr.<
EwuRIe;D
/** J~oxqw}
* @param userDAO The userDAO to set. .)p%|A#^
*/ .c @Y?..+
publicvoid setUserDAO(UserDAO userDAO){ DnG9bVm>
this.userDAO = userDAO; W2zG"Q
} F;kKn:X L
YU)%-V\
/* (non-Javadoc) ~F-lO1
* @see com.adt.service.UserManager#listUser bKzG5|Qu
6U$e;cr6
(org.flyware.util.page.Page) `_i|\}tl
*/ v<<ATs%w
public Result listUser(Page page)throws Dsc0;7~6
njO~^Hl7
HibernateException, ObjectNotFoundException { Yo=$@~vN]
int totalRecords = userDAO.getUserCount(); o~L(;A]yN
if(totalRecords == 0) ~Lg ;7i1L
throw new ObjectNotFoundException EE`[J0 (
uqa
pj("
("userNotExist"); BIew\N
page = PageUtil.createPage(page, totalRecords); V}7)>i$A
List users = userDAO.getUserByPage(page); bhbTloCR
returnnew Result(page, users); %;= ?r*]
} FKL@,>!<e
0E,QOF{o
} fR+{gazk
n
#b:YY^{g_
gu~R4@3
B.;@i;7L
3^-R_
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 "USzk7=&.
%6Vb1?x
询,接下来编写UserDAO的代码: kzNRRs\e
3. UserDAO 和 UserDAOImpl: KK4e'[Wf
java代码: )PYh./_2
%|^,Q -i,
?9!9lSH6%
/*Created on 2005-7-15*/ H+]h+K9\7
package com.adt.dao; fo`R=|L[
UUZm]G+
import java.util.List; p5w9X+G%
#Ufb
import org.flyware.util.page.Page; Ex|Z@~T12
1^V.L+0s]
import net.sf.hibernate.HibernateException; Bg zq
uudd'L
/** DHuvHK0#
* @author Joa 5} ur,0{
*/ <sM_zoprc
publicinterface UserDAO extends BaseDAO { U>bIQk"4
'irwecd8
publicList getUserByName(String name)throws }$qrNbLJ
skTaIGRL
HibernateException; r$'.$k\
]@Z
nP,8
publicint getUserCount()throws HibernateException; ,O:p`"3`0=
1ah,Zth2
publicList getUserByPage(Page page)throws ,Shzew+
wq!9wk9
HibernateException; :hW(2=%
tX@y ]"
} _T~&kwe
MU2kA&LH
Soe2Gq
v6Y[_1
rz-61A) _
java代码: Z(tO]tQE
0aI@m
<Kr`R+Q$DN
/*Created on 2005-7-15*/ ADB)-!$xoi
package com.adt.dao.impl; O;McPw<&\:
*8;<w~
import java.util.List; ' S,g3
gzH;`,
import org.flyware.util.page.Page; @JLN3
}NGP!
import net.sf.hibernate.HibernateException; hNkv lk'Ui
import net.sf.hibernate.Query; PVdN)tG5
~)>.%`v&
import com.adt.dao.UserDAO; ZGI<L
?p 4iXHE
/** >"b\$",~6
* @author Joa c93 Ok |
*/ &`vThs[x
public class UserDAOImpl extends BaseDAOHibernateImpl #.fJ
M:"tG
dn?'06TD
implements UserDAO { a.JjbFL
?$tD
/* (non-Javadoc) L]"$dF
* @see com.adt.dao.UserDAO#getUserByName b\o>4T
< .e4
(java.lang.String) f#!nj]}#
*/ 1q5S"=+W[
publicList getUserByName(String name)throws Q8QB{*4
:sLg$OF
HibernateException { (JnEso-V
String querySentence = "FROM user in class TgDT
K3h7gY| .
com.adt.po.User WHERE user.name=:name"; nR@mm
j
Query query = getSession().createQuery q@XJ,e1A
w'$>E4\
(querySentence); +ug/%Iay{k
query.setParameter("name", name); Ygkf}n
return query.list(); ?1Vx)j>|
} T"C.>G'[B
,)J>8eV
/* (non-Javadoc) (a-Lx2 T
* @see com.adt.dao.UserDAO#getUserCount() z
j#<X
*/ S
Te8*=w
publicint getUserCount()throws HibernateException { F0zaA
int count = 0; YPq:z"`-y4
String querySentence = "SELECT count(*) FROM .V0fbHYTJ
G?\eO&QG{"
user in class com.adt.po.User"; Ex*{iJ;\
Query query = getSession().createQuery {}iS5[H]
u8|CeA
(querySentence); '73}{" '
count = ((Integer)query.iterate().next
t]]Ig
0:4>rYBC
()).intValue(); _K'Y`w']
return count; \+Y=}P>
} 0c!^=(
KD+&5=Y
/* (non-Javadoc) Bj><0
cNF
* @see com.adt.dao.UserDAO#getUserByPage KU0Ad);e
q(hBqU W
(org.flyware.util.page.Page) 9kqR-T|Q
*/ fZsw+PSy
publicList getUserByPage(Page page)throws vSoG] :1
N=T}
HibernateException { )8}k.t>'s
String querySentence = "FROM user in class WJa7
F:jtzy"
com.adt.po.User"; 9xw"NcL
Query query = getSession().createQuery dBovcc
7^M$u\a)U
(querySentence); p W5D!z
query.setFirstResult(page.getBeginIndex()) j;D$qd'J
.setMaxResults(page.getEveryPage()); D0kz;X
return query.list(); 8*{jxN'M
} :)B1|1
}0@@_Y]CC
} s?->2gxhx
Y+vIU*O
+\&6Zbn
~=[5X,Ta
U#iW1jPE2
至此,一个完整的分页程序完成。前台的只需要调用 #6[F&
l7VTuVGUJ
userManager.listUser(page)即可得到一个Page对象和结果集对象 F|.tn`j]U
zzo93d
的综合体,而传入的参数page对象则可以由前台传入,如果用 8<C@I/
$9X?LGUz
webwork,甚至可以直接在配置文件中指定。 vJVh%l+
}''0N1,/
下面给出一个webwork调用示例: 3c wBPqH
java代码: #;@I.
a$^)~2U{
Pw7uxN`
/*Created on 2005-6-17*/ P,WQN[(+
package com.adt.action.user; <}8G1<QZ'.
S0:Oep
import java.util.List; k&f/f
]F>#0Rdc
import org.apache.commons.logging.Log; eK*oV}U-k
import org.apache.commons.logging.LogFactory; Mk973'K'
import org.flyware.util.page.Page; 9h)8Mq+M
:~srl)|)
import com.adt.bo.Result; *HGhm04F{
import com.adt.service.UserService; v+79#qWK|n
import com.opensymphony.xwork.Action; W_ Hoa*~
.;ofRx<
/** RF'nwzM3
* @author Joa s] ;P<
*/ D2gyn-]\
publicclass ListUser implementsAction{ um_J%v6ER
" Qyi/r41
privatestaticfinal Log logger = LogFactory.getLog *f>\X[wN
Jq? zr]"A
(ListUser.class); a'Zw^g
Wc!]X.|9*
private UserService userService; HyKA+7}
1n7'\esC*
private Page page; $G }9iV7
h# Z,ud_
privateList users; }m5()@Q}a
Q{'4,J-w
/* *vIP\NL?H
* (non-Javadoc) 2*#i/SE_
* PN<VqtW
* @see com.opensymphony.xwork.Action#execute() EfpMzD7/(
*/ Ij =NcP
publicString execute()throwsException{ ]SPuNBsy)
Result result = userService.listUser(page); :2
:VMIa
page = result.getPage(); 1-PlRQs.1
users = result.getContent(); (3!6nQj-t
return SUCCESS; N'aq4okoL
} ]vs}-go
k\j_hu
/** "%a<+D
* @return Returns the page. %,
iAngF'
*/ JZ5 ";*,
public Page getPage(){ birc&<
return page; -U
A &Zt
} JXq!v:w6
~jHuJ`]DF
/** /N<aN9Z<x,
* @return Returns the users. mXS]SE
*/ XK@&$~iA3
publicList getUsers(){ 3RvDX p
return users; mv~?1aIKD
} zb"4_L@m2
PeqW+Q.
/** 3tJfh=r=1
* @param page !~R<Il|B
* The page to set. !.t D.(XP
*/ 74:~F)BP
publicvoid setPage(Page page){ rKFnivGT
this.page = page; $M!iQ"bb
} w4}Q6_0v
K{`R`SXD
/** lA1
* @param users y06**f)
* The users to set. Tbv w?3
*/ ~tRGw^<9
publicvoid setUsers(List users){ Is<XMR|{
this.users = users; j%w^8}U>G
} hAc|a9 o
LW.j)wB]
/** \)o.Y
zAo@
* @param userService X/vyb^:U
* The userService to set. $\/^O94-l
*/ JN` $Fq+
publicvoid setUserService(UserService userService){ HQ7g0:-^a>
this.userService = userService; A?}[rM
Z
} w $-q&
} i|AWaG)
I=<Qpd4
u7RlxA:
:#?_4D!r
/d:hW4}<}.
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, hxM{}}.E
b)e;Q5Z(.
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 _kMHF
YVgH[-`,
么只需要: 5XB]p|YU~s
java代码: MMpId
Uhr
'7oCWHq[
ITqAy1m@C
<?xml version="1.0"?> 3c,4 wyn
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 39
zfbxX
U!uJ )mm
1.0//EN" "http://www.opensymphony.com/xwork/xwork- E0fMFG^P
~|O; Sdo=
1.0.dtd"> )`'a1y|
S5ai@Ksf
<xwork> {,h_T0D^j
bfZt <-
<package name="user" extends="webwork- ~]d 9 J
fpC":EX@r
interceptors"> k+P3z&e
(hZNWQ0
<!-- The default interceptor stack name :):vB
,]: <l
--> *c/V('D/
<default-interceptor-ref m;{HlDez
!9KDdU
name="myDefaultWebStack"/> W#NZnxOX"
\#Jq%nd
<action name="listUser" -=gI_wLbM
x7<l*WQ
class="com.adt.action.user.ListUser"> fKr_u<|
<param v^s?=9
0|j44e}
name="page.everyPage">10</param> ~?fl8RF\
<result MD<x{7O12>
n w`rH*
name="success">/user/user_list.jsp</result> YsVKdh
</action> e Ru5/y~
HK<S|6B7V
</package> u pUJF`3
{^N,$,Ab.
</xwork> O#18a,o@
G7+ {O7
*C+[I
=>3,]hnep
gzSm=6Qw0
"9aFA(H6w
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 er-0i L@
[hg9 0Q6
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。 K39I j_3
/.!&d^
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 >yP>]r+
- ry
Yu_
eCq5/
4~$U#$u_
~J+
qIZge
我写的一个用于分页的类,用了泛型了,hoho e],(d7 Jo
RfD#/G3|
java代码: U_gkO;s%
*!BQ1] G
;^0ok'P\~9
package com.intokr.util; =LK`mNA
.B2e$`s$
import java.util.List; M!!vr8}
!]A/ID0K
/** N5=}0s]e
* 用于分页的类<br> ^mFsrw
* 可以用于传递查询的结果也可以用于传送查询的参数<br> w_@{v wM$A
* qk3~]</
* @version 0.01 iM:-750n/
* @author cheng G:lhrT{
*/ ps,Kj3^T<
public class Paginator<E> { zZRLFfz<9
privateint count = 0; // 总记录数 tB`"gC~
privateint p = 1; // 页编号 Viw,YkC
privateint num = 20; // 每页的记录数 <b_K*]Z
privateList<E> results = null; // 结果 sg}<()
4f8XO"k7t=
/** u #}1
M
* 结果总数 V/"RCqY4
*/ ;Wk3>\nT-
publicint getCount(){ +,ar`:x&a
return count; H\<0{#F
} C\BKdx5;
yY49JZ
publicvoid setCount(int count){ h;r^9g
this.count = count; |P|2E~[r
} &Fuk+Cu{
Zj ` ;IYFG
/**
fB]2"(
* 本结果所在的页码,从1开始 OiZ-y7;k^
* '@#(jY0_
* @return Returns the pageNo. /`aPV"$M
*/ t4:/qy
publicint getP(){ 7zE1>.
return p; m
zoH$@
} =X[?d/[
Nr,I`x\N
/** GtIAsC03
* if(p<=0) p=1 )y:))\>
* RN@)nc_
* @param p bZfq?
*/ 4,X CbcC
publicvoid setP(int p){ bVN?7D(
if(p <= 0) _]Ob)RUVH
p = 1; qyKR]%yzi
this.p = p; =+DhLH}8
} nC??exc
eUCBQK
/** 7iM@BeIf
* 每页记录数量 BLqK5~
*/ <^KW7M}w*c
publicint getNum(){ _G<Wq`0w)
return num; G}NqVbZ9]
} ><S2o%u~
5pY|RV6:
/** saQ
~v@
* if(num<1) num=1 Y*#TfWv:
*/ ls9Y?
publicvoid setNum(int num){ 8JR&s
if(num < 1) :ntAU2)H
num = 1; #FRm<9/j
this.num = num; 46 \!W(O~y
} '4~I%Z7L
a"g\f{v0AR
/** zn^ G V
* 获得总页数 Rh
]XJM
*/ Qu8=zI>t
publicint getPageNum(){ ZDI?"dt{
return(count - 1) / num + 1; O6b+eS
} ?LU>2!jN
>zfx2wh\a
/** A8S9HXL
* 获得本页的开始编号,为 (p-1)*num+1 8$iHd
*/ |{ZdAr.;
publicint getStart(){ x*TJYST
return(p - 1) * num + 1; k_?OEkgUh
} | lzcyz
Nqd9)WQ
/** N,VI55J:y>
* @return Returns the results. 4JO16
*/ KE5>O1
publicList<E> getResults(){ xc`O\z_)
return results; M80O;0N%A
} 7aPA+gA/
c3PA<q[
public void setResults(List<E> results){ <)sL8G9Y
this.results = results; *(]ZdB_2
} `}$bJCSF.n
Jx`7W1%T
public String toString(){ +eLL)uk
StringBuilder buff = new StringBuilder }jWg&<5+z
mC0Dj O
(); i=P}i8,^=
buff.append("{"); THK^u+~LM
buff.append("count:").append(count); *a{WJbau]
buff.append(",p:").append(p); /!p}H'jl
buff.append(",nump:").append(num); f;,*P,K
buff.append(",results:").append 0blbf@XA
[fvjvN`
(results); r5(efTgAd+
buff.append("}"); s+&0Z3+
return buff.toString(); N$:-q'hX
} JlRNJ#h>
WI&}94w
} H%Lln#
_E6N*ORV
zq ?xY`E