Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 v(Vm:oK,
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 i
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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 f+A!w8E
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分页支持类: a-nf5w>&q
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java代码: |n9q4*dN
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package com.javaeye.common.util; e[5=?p@|
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import java.util.List; {~cG'S Y%
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publicclass PaginationSupport { -s]
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publicfinalstaticint PAGESIZE = 30; %M?A>7b
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privateint pageSize = PAGESIZE; M{sn{
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privateList items; =^nb-9.
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privateint totalCount; s>d /9 b
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privateint[] indexes = newint[0]; ,gdf7&r
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privateint startIndex = 0; BbCt_z'
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public PaginationSupport(List items, int fDq`.ZW)s
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totalCount){ Z:TW{:lrI
setPageSize(PAGESIZE); X?3?R\/
setTotalCount(totalCount); IiX`l6L~W
setItems(items); A4C4xts]N
setStartIndex(0); FrPpRe %!
} hSBR9g
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public PaginationSupport(List items, int +i %,+3#6
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totalCount, int startIndex){ ux8:
setPageSize(PAGESIZE); HTpoYxn(
setTotalCount(totalCount); ^M51@sXI7
setItems(items); I $5*Puy#
setStartIndex(startIndex); f76bEe/B9
} fe,A\W&8
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public PaginationSupport(List items, int f;Cu@z{b
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totalCount, int pageSize, int startIndex){ gWqO5C~h
setPageSize(pageSize); S7/0B4[
setTotalCount(totalCount); E~k_4z%M
setItems(items); ;JNI$DR
setStartIndex(startIndex); x{Gdr51%
} xKol
@(;zU~l/
publicList getItems(){ yP&SA+
return items; GQU9UXe
} /.?m9O^
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publicvoid setItems(List items){ k@,&'imx
this.items = items; hqPpRSv'
} #5Zf6w
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publicint getPageSize(){ WJB/X"J
return pageSize; vai.w-}Z
} oH[4<K>
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publicvoid setPageSize(int pageSize){ kO1.27D
this.pageSize = pageSize; 4sj:%%UE
} ^CZ)!3qd1
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publicint getTotalCount(){ S6J7^'h
return totalCount; yUZ;keQ_Tw
} f]P&>j|
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publicvoid setTotalCount(int totalCount){ O{B[iy(C
if(totalCount > 0){ 3]*_*<D
this.totalCount = totalCount; 3`W=rIMli
int count = totalCount / %Q)3*L
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pageSize; 4{[cXM8*j
if(totalCount % pageSize > 0) 8SG*7[T7
count++; 3,7SGt
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indexes = newint[count]; /1h
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for(int i = 0; i < count; i++){ !jV}sp<Xp
indexes = pageSize * RsY7F;
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} ( k@%04c
}else{ w]BZgF.
this.totalCount = 0; ,+iREh;
} h^u 9W7.
} m'
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publicint[] getIndexes(){ o0f{ePZ=
return indexes; G^Z
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} ";I|\ T
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publicvoid setIndexes(int[] indexes){ ~"oxytJ
this.indexes = indexes; 71nI`.Z
} W6b5elH@
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publicint getStartIndex(){ ]3+xJz~=
return startIndex; j'z}m+_?
} 5CSihw/5
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publicvoid setStartIndex(int startIndex){ i2PPVT
if(totalCount <= 0) ql|ksios
this.startIndex = 0; GsYi/Z
elseif(startIndex >= totalCount) 7y4!K$c$
this.startIndex = indexes rUb`_ W@
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[indexes.length - 1]; ^'UJ&UfX
elseif(startIndex < 0) r9x.c7=O
this.startIndex = 0; :3,aR\
else{ L5E|1T
this.startIndex = indexes 1T{A(<:o$
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[startIndex / pageSize]; ~S\Ee 2e>
} *?k~n9n5U
} uC_&?
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publicint getNextIndex(){ %&c+}m
int nextIndex = getStartIndex() + E(5'vr0
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pageSize; xB1Oh+@i
if(nextIndex >= totalCount) _x.!,
g{
return getStartIndex(); \2F$FRWo
else E1atXx
return nextIndex; ews4qP
} 1gq(s2izy
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publicint getPreviousIndex(){ G8m:]!
int previousIndex = getStartIndex() - &x}a
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pageSize; H.8f-c-4we
if(previousIndex < 0) JN{.-k4Ha
return0; g$++\%k&
else i+I%]
return previousIndex; LuM[*_8
} rek89.p
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} Us4ijR d
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抽象业务类 {X=gjQ9
java代码: T.1*32cX
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/** dS7?[[pg9
* Created on 2005-7-12 D ^ mfWJS
*/ QLq^[>n
package com.javaeye.common.business; w7.I0)MH
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import java.io.Serializable; \r_-gn'1b
import java.util.List; O-rHfIxY
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import org.hibernate.Criteria; -}l iG
import org.hibernate.HibernateException; &N{XLg>
import org.hibernate.Session; /V66P@[>
import org.hibernate.criterion.DetachedCriteria; )qGw!^8
import org.hibernate.criterion.Projections; 67/&AiS?
import <&n\)R4C1
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org.springframework.orm.hibernate3.HibernateCallback; ;&|MNN^
import gZ!vRO<%
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org.springframework.orm.hibernate3.support.HibernateDaoS aS^
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upport; HPGMR4=ANS
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import com.javaeye.common.util.PaginationSupport; (Rqn)<<2
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public abstract class AbstractManager extends icq!^5BzL
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HibernateDaoSupport { b'
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privateboolean cacheQueries = false; 5iE-$,7#L
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privateString queryCacheRegion; 3h:"-{MW.
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publicvoid setCacheQueries(boolean \,YF['Qq
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cacheQueries){ N5>ioJj
this.cacheQueries = cacheQueries; by 'P}
} 9oOr-9t3
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publicvoid setQueryCacheRegion(String `|Aj3a3sND
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queryCacheRegion){ [O)
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this.queryCacheRegion = 9M3XHj
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queryCacheRegion; =Q#}
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} xgw[)!g^\
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publicvoid save(finalObject entity){ q; &\77i$
getHibernateTemplate().save(entity); FerQA9K)x
} QnsD,F; /
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publicvoid persist(finalObject entity){ gq[|>Rs75
getHibernateTemplate().save(entity); ,e6n3]W8
} ,+0#.Ns$
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publicvoid update(finalObject entity){ rkdf htpI
getHibernateTemplate().update(entity); 1P(5+9"s
} aS
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publicvoid delete(finalObject entity){ ,>H(l$n
getHibernateTemplate().delete(entity); gi26Dtk(h
} X?m"86L
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publicObject load(finalClass entity, V6opV&
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finalSerializable id){ J2rw4L
return getHibernateTemplate().load 4bV&U=
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(entity, id); (/x%zmY;/U
} nE$8-*BZ_
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publicObject get(finalClass entity, 13+f ^
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finalSerializable id){ r_8[}|7;
return getHibernateTemplate().get F:p'%#3rU/
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(entity, id); `zD]*i(
} M4MO)MYJ
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publicList findAll(finalClass entity){ T8nOb9Nrj
return getHibernateTemplate().find("from ZbmBwW_ 7
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" + entity.getName()); uBdS}U
} _gAU`aO^
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publicList findByNamedQuery(finalString uVnbOqR<X
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namedQuery){ dD%Sbb
return getHibernateTemplate j2@19YXe@
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().findByNamedQuery(namedQuery); ;ps0wswX
} 6N7^`ghTf
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publicList findByNamedQuery(finalString query, lB7 V4
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finalObject parameter){ 7w}PYp1Z'~
return getHibernateTemplate N0]C?+
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().findByNamedQuery(query, parameter); 5somoV B
} ,hMdxZJd
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publicList findByNamedQuery(finalString query, dfo_R
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finalObject[] parameters){ 33O O%rWi
return getHibernateTemplate y7iHB
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().findByNamedQuery(query, parameters); n U0
} -SyQ`V)T7N
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publicList find(finalString query){ rn$LZE
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return getHibernateTemplate().find -0pAj}_2}
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(query); mpsi{%gA
}
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publicList find(finalString query, finalObject /w5~ O:
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parameter){ P4h^_*d
return getHibernateTemplate().find %jS#DVxBR
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(query, parameter); #YABbwH
} u~JCMM$
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public PaginationSupport findPageByCriteria =Gl6~lJ{_
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(final DetachedCriteria detachedCriteria){ \{g;|Z1
return findPageByCriteria y{Fq'w!ap
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); @<^_ _."
} qD#E, "%
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public PaginationSupport findPageByCriteria Mk:k0,z
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(final DetachedCriteria detachedCriteria, finalint APne!
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startIndex){ n ]K`ofjl^
return findPageByCriteria \J)ffEKIp
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(detachedCriteria, PaginationSupport.PAGESIZE, 0 It[Pa qG
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startIndex); XIS.0]~
} '4T]=s~N
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public PaginationSupport findPageByCriteria QTy xx
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(final DetachedCriteria detachedCriteria, finalint <'Ppu
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pageSize, Zze(Ik
finalint startIndex){ <Z0N)0|
return(PaginationSupport) $qvk9 B0E
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getHibernateTemplate().execute(new HibernateCallback(){ F:3*i^ L
publicObject doInHibernate RV%aFI )
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(Session session)throws HibernateException { 49e~/YY
Criteria criteria = _0razNk
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detachedCriteria.getExecutableCriteria(session); E~b Yk6
int totalCount = 2r0u[
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((Integer) criteria.setProjection(Projections.rowCount rM{3]v{~
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()).uniqueResult()).intValue(); %-A #7\
criteria.setProjection {}Q A#:V
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(null); *[ @k=!73
List items = y*f5_
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criteria.setFirstResult(startIndex).setMaxResults S4'\=w#
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(pageSize).list(); <`rl[C{
PaginationSupport ps = r )pg9}+
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new PaginationSupport(items, totalCount, pageSize, N:_U2[V^d
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startIndex); c)7i%RF'
return ps; 7aV(tMzd
} Os9;;^k
}, true); D>HX1LV
} qi ;X_\v
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public List findAllByCriteria(final :(^,WOf
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DetachedCriteria detachedCriteria){ rX^wNH
return(List) getHibernateTemplate _NkVi_UX
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().execute(new HibernateCallback(){ qYwEPGa\
publicObject doInHibernate O<:"Irq\qr
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(Session session)throws HibernateException { ]O\m(of
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Criteria criteria = DbL=2
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detachedCriteria.getExecutableCriteria(session); CP%?,\
return criteria.list(); bPe|/wp
} 5LIbHSK
}, true); gM5`UH|
} e1
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public int getCountByCriteria(final NrNxI'MG
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DetachedCriteria detachedCriteria){ (,i&pgVZ
Integer count = (Integer) aYmC LLj
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getHibernateTemplate().execute(new HibernateCallback(){ +VN&kCx)
publicObject doInHibernate 4ox[,
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(Session session)throws HibernateException { *k (|r>
Criteria criteria = L^7"I 4=(D
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detachedCriteria.getExecutableCriteria(session); 'f?=ks<
return b!pG&7P
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criteria.setProjection(Projections.rowCount 8
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()).uniqueResult(); ~zcHpxO^W
} d/m.VnW
}, true); IwR/4LYI
return count.intValue(); /c>@^
} =Eh~ wm
} sNF[-,a
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用户在web层构造查询条件detachedCriteria,和可选的 K).Gj2 $
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 [q%Rx!L
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PaginationSupport的实例ps。 +TWk}#G
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ps.getItems()得到已分页好的结果集 <6djdr1:b
ps.getIndexes()得到分页索引的数组 5V{>
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ps.getTotalCount()得到总结果数 !n?8'eqWru
ps.getStartIndex()当前分页索引 &F!Ct(c99
ps.getNextIndex()下一页索引 $N[R99*x8
ps.getPreviousIndex()上一页索引 (9_O||ee
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 lV*dQwa?i
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 j\uh]8N3<
q\`0'Z,
一下代码重构了。 >7[o=!^:4
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我把原本我的做法也提供出来供大家讨论吧: Q8~|0X\.g
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首先,为了实现分页查询,我封装了一个Page类:
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java代码: whoQA}X>
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/*Created on 2005-4-14*/ v{T%`WuPRf
package org.flyware.util.page; s_p\
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/** [|&V$
* @author Joa 9c}mAg4
* a9"1a'
*/ [@PD[-2QG3
publicclass Page { >,&@j,?']
o-f;$]yp>
/** imply if the page has previous page */ ;4!,19AT
privateboolean hasPrePage; |k:ecw
bRhc8#kw)
/** imply if the page has next page */ He}uE0^
privateboolean hasNextPage; $1F$3"k
G 5T{*
/** the number of every page */ !L=RhMI
privateint everyPage; b":3J)Y6.
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/** the total page number */ C;EC4n+s
privateint totalPage; y;r{0lTB
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/** the number of current page */ Vp.&X 8
privateint currentPage; !UV1OU
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/** the begin index of the records by the current QR#L1+Hn
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query */ 0|^/ e-^
privateint beginIndex; Z +vT76g3
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/** The default constructor */ W|yFjE&dr
public Page(){ 68
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} ;
{ MK
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/** construct the page by everyPage r) SG!;X
* @param everyPage 8F;f&&L"y
* */ yG ,oSp|
public Page(int everyPage){ #j?SdQ
this.everyPage = everyPage; x&N!SU6
} B'kV.3t
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/** The whole constructor */ ,+Bp>=pvs
public Page(boolean hasPrePage, boolean hasNextPage, w9W0j
K*]^0
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int everyPage, int totalPage, .GM}3(1fX`
int currentPage, int beginIndex){ _x&fK$Y)B
this.hasPrePage = hasPrePage; :1Y *&s
this.hasNextPage = hasNextPage; nz}}m^-j
this.everyPage = everyPage; bFv,.(h'
this.totalPage = totalPage; 4uV,$/
this.currentPage = currentPage; M`=bJO:
this.beginIndex = beginIndex; [JzOsi~R
} 5{esL4k
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/** 0)^$9Z
* @return G8Qo]E9-/
* Returns the beginIndex. !idQ-&
*/ jlA?JB
publicint getBeginIndex(){ yW!+:y_N_
return beginIndex; ?L'4*S]
} V|njgcn d
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/** @#?w>38y
* @param beginIndex J: T
* The beginIndex to set. 1vG]-T3VC
*/ =/6rX"\P
publicvoid setBeginIndex(int beginIndex){ nbhzLUK
this.beginIndex = beginIndex; n1mqe*Mvs/
} {Iu9%uR>@
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/** TlA*~HG<Q
* @return iax6o+OG|
* Returns the currentPage. F\H^=P
*/ Jm5&6=
publicint getCurrentPage(){ bTrQ(qp
return currentPage; yOQEF\
} \dG#hH4ZD
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/** u]Eyb),Gy
* @param currentPage *@C]\)
* The currentPage to set. yE80*C~d
*/ `~.0PnHf
publicvoid setCurrentPage(int currentPage){ UyWKE<
this.currentPage = currentPage; aV6l"A]
} M10u?
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/** JBCJVWUt
* @return {;kH&Pp
* Returns the everyPage. :AzP3~BI
*/ -$8M#n,
publicint getEveryPage(){ +~H mPQ
return everyPage; ' >F_y t9
} .AzGPcJY
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/** "V>7u{T
* @param everyPage R06zca
* The everyPage to set. R'.YE;leBG
*/ jxt^d
publicvoid setEveryPage(int everyPage){ VHUOI64*
this.everyPage = everyPage; 'h:[[D%H`
} U_/<tWl\[3
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/** 2Y2J)5,
* @return G]T A7~VT
* Returns the hasNextPage. UhX`BGpM{
*/ ` s}v6
publicboolean getHasNextPage(){ .).*6{_
return hasNextPage; `c-(1;Jb
} ~5f|L(ODX
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/** [8sL);pJO
* @param hasNextPage X` QfOs#\
* The hasNextPage to set. NUclF|G
*/ Ju~8C\Dd
publicvoid setHasNextPage(boolean hasNextPage){ BwN>;g_
this.hasNextPage = hasNextPage; gkN|3^
} OFtAT@=O
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/** :<`hsKy&
* @return 'aWzam>
* Returns the hasPrePage. OSvv\3=
*/ lk5}bnd5
publicboolean getHasPrePage(){ O0lQ1<=
return hasPrePage; SAa
hkX
} /wjL<
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/** tVf 1]3(_>
* @param hasPrePage LAoX'^6
* The hasPrePage to set. gXR1nnK
*/ %mda=%Yn
publicvoid setHasPrePage(boolean hasPrePage){ x7s75
this.hasPrePage = hasPrePage; $jDp ^ -
} m>@$T
x
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/** I&}Md73
* @return Returns the totalPage. !u}} V
* kdWk{ZT^
*/ X5@rPGc
publicint getTotalPage(){ CpAdE m{
return totalPage; qX(sx2TK
} 0CYm%p8!
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/** "ct_EPr`
* @param totalPage ?\7" A
* The totalPage to set. NINaOs
*/ Cu%|}xq
publicvoid setTotalPage(int totalPage){ [y>;[K
this.totalPage = totalPage; F?LTWm
} 0 w"&9+kV
4YVxRZ1[3
} XG5mfKMt+
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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 P2nb&lVdu
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个PageUtil,负责对Page对象进行构造: *lN>RWbM%
java代码: &k5 Z|d|
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/*Created on 2005-4-14*/ <tEN1i
package org.flyware.util.page; Ou
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import org.apache.commons.logging.Log; ACg5"
import org.apache.commons.logging.LogFactory; T[iwP~l
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/** 3
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* @author Joa x)hp3&L
* x.7Ln9
*/ Y%UfwbX!g
publicclass PageUtil { _fH.#C
8"a[W3b
privatestaticfinal Log logger = LogFactory.getLog
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(PageUtil.class); 5o~;0K]
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/** dpO ZqhRs.
* Use the origin page to create a new page (8<U+)[tPy
* @param page 1)aB']K%
* @param totalRecords :bLLN
* @return FuNc#n>
*/ zY<=r.m4
publicstatic Page createPage(Page page, int c}II"P
C?bq7kD:H
totalRecords){ +jFcq:`#UG
return createPage(page.getEveryPage(), |wKC9 O@%
CQo<}}-o
page.getCurrentPage(), totalRecords); %Ot22a
} Q']
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/** /?%zNkcxu
* the basic page utils not including exception 4VjP:>*p
qV$\.T>x
handler A0SEzX({[
* @param everyPage \:
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* @param currentPage C?e1 a9r
* @param totalRecords .0:twj
* @return page [s-Km/
*/ S
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publicstatic Page createPage(int everyPage, int "-Lbz)k
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currentPage, int totalRecords){ C>q,c3s5
everyPage = getEveryPage(everyPage); V:rq}F}
currentPage = getCurrentPage(currentPage); **V^8'W<
int beginIndex = getBeginIndex(everyPage, /jQW4eW0
ZqQJFyV*
currentPage); >!|Hns
int totalPage = getTotalPage(everyPage, wRL=9/5(8
0/d+26lR
totalRecords); 33lD`4i+
boolean hasNextPage = hasNextPage(currentPage, $UMxO`F
u@\]r 1
totalPage); H gMLh*
boolean hasPrePage = hasPrePage(currentPage); gaaW:* *y
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returnnew Page(hasPrePage, hasNextPage, ZPWY0&9
everyPage, totalPage, ~^QL"p:5|
currentPage, 3jIi$X06
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beginIndex); ?b0 VB
} MR/jM@8
\}Jy=[
privatestaticint getEveryPage(int everyPage){ TC1#2nE&T
return everyPage == 0 ? 10 : everyPage; k:nR'TI
} ;7"}I
8BC F.y
privatestaticint getCurrentPage(int currentPage){ JPQ[JD^]
return currentPage == 0 ? 1 : currentPage; W is_N3M
} 'v.i' 6
)A9K9pZj
privatestaticint getBeginIndex(int everyPage, int D.H$4[u;j
wt4uzg8
currentPage){ |;o#-YosP
return(currentPage - 1) * everyPage; 9"g=it2Rh6
}
,vEwck#
&B\tcF
privatestaticint getTotalPage(int everyPage, int > $0eRVL
"ZDc$v:Qa
totalRecords){ N.OC _H&
int totalPage = 0; wkK61ah6
/238pg~Cw5
if(totalRecords % everyPage == 0)
RKsr}-18
totalPage = totalRecords / everyPage; $:kG>R@\t
else \TSt
totalPage = totalRecords / everyPage + 1 ; eOa:%{Kj
:B?XNo
return totalPage; oR>o/$z$)g
} ,.tv#j|A
YB/A0 J
privatestaticboolean hasPrePage(int currentPage){ Tx%6whd/'
return currentPage == 1 ? false : true; &K5wCNX1
} i.Iiwe0G
R9Wh/@J]
privatestaticboolean hasNextPage(int currentPage, e0%?;w-TL
_Z'j%/-4@D
int totalPage){ OI"vC1.5
return currentPage == totalPage || totalPage == /gZrnd?
Qhb].V{utV
0 ? false : true; S~fQ8t70
} $e#p -z
l\7N R
'+1<7jl&I
} s0"S;{_#
',k0_n?t
K*Y.mM)
:nYl]Rm
}R:e[lKj
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 ^& ZlV
ab8uY.j
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 1TbY,3W
VyH'7_aU
做法如下: y6ntGrZ}$
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ^OKCvdS
<d~P;R(@
的信息,和一个结果集List: DytH} U"
java代码: ~TCz1UWV
aObWd5~
|i'V\"
hW
/*Created on 2005-6-13*/ Y<M,/Y_ !
package com.adt.bo; J
>Zd0Dn
/v"u4Ipj
import java.util.List; rH7|r\] r
~Emeo&X
import org.flyware.util.page.Page; 8qL*Nf
dABmK;
/** sh(G{Yz@
* @author Joa #?.Yc%5B
*/ yS0YWqv]6@
publicclass Result { @mBZu!,
N*w/\|
private Page page; kFmd):U!R
%7 h_D
private List content; <CIJg*
mw)KyU#l,:
/** F2!C^r,~L
* The default constructor !K^.r_0H.
*/ IBWUXG;
public Result(){ &3lg\&"
super(); _2+}_ >d
} &
.VciSq6
o5KpiibFM
/** XL>v$7`#
* The constructor using fields I*_@WoI*
* ^l|{*oj2
* @param page WCT}OiLsL
* @param content ;$Q`JN=
*/ bI.LE/yk
public Result(Page page, List content){ K5gh7
this.page = page; ^T`)ltI]V
this.content = content; X[b= 25Ct
} 1 zIFQ@
VAf"B5R
/** .w3.zZ0[
* @return Returns the content. vcs=!Ace
*/ R{GOlxKs C
publicList getContent(){ XB,
2+
return content; KB49~7XjQ@
} t98t&YUpm
s*{l}~fPkW
/** Pn|A>.)z
* @return Returns the page. i-[ic!RnKj
*/ hN*,]Z{
public Page getPage(){ uu L"o
return page; c'n EbelE
} /tI8JXcUK
n{JBC%^g
/** M72.
* @param content asqbLtQ
* The content to set. _4F(WC co
*/ wYy=Tl-N
public void setContent(List content){ c?B@XIl
this.content = content; f tW-
} $Kgw6
PjZsMHW%
/** {]1o($.u
* @param page Yl%1e|WV
* The page to set. `>&V_^y+
*/ a;JB8
publicvoid setPage(Page page){ (A(7?eq
this.page = page; p>Dv&fX
} gSQq
} }&A!h
$5kb3x<W
DXu915
FrBoE#
6lw)L
2. 编写业务逻辑接口,并实现它(UserManager, GlkTpX^b
NrH2U Jm
UserManagerImpl) FJo?~
java代码: _u TaN
-t~l!!N(
ApHs`0=(
/*Created on 2005-7-15*/ +{U0PI82
package com.adt.service; A\p'\@f
]OIB;h;3
import net.sf.hibernate.HibernateException; Zp@j*P
ax$ashFO/!
import org.flyware.util.page.Page; ~<
%%n'xmm
l,j7I3&~%
import com.adt.bo.Result; KvENH=oh
<[mT*
/** _'DT)%K
* @author Joa iJ n<
*/ jMv qKJ(<
publicinterface UserManager { -|;{/ s5
V45A>#?U
public Result listUser(Page page)throws Vb^P{F
KZoIjK]
HibernateException; %(lr.9.]H
R-8>,
} B].V|8h
nmIos]B
buV{O[
~ 8L]!OQ9=
T
DOOq;+
java代码: k4:$LFw@
K|JpkEw
D5lzrpg _e
/*Created on 2005-7-15*/ dqF]kP,VG
package com.adt.service.impl; IoO t n
BfZAK0+*$
import java.util.List; n;&08M5an}
EB R,j_
import net.sf.hibernate.HibernateException; ]}7FTMGbY
E4;vC ?K{
import org.flyware.util.page.Page; 8~*<s5H
import org.flyware.util.page.PageUtil; x!5b"
"
I/YBL
import com.adt.bo.Result; 8@;|x2=y
import com.adt.dao.UserDAO; k1Z"Qmz
import com.adt.exception.ObjectNotFoundException; f_A'.oq+
import com.adt.service.UserManager; +tO mKY
j9Qd
45
/** `pr$l
* @author Joa ?VCdT`6=
*/ U9w0kcUw#J
publicclass UserManagerImpl implements UserManager { #r5IwyL
(gW#T\Eln
private UserDAO userDAO; t~vOm
,U`:IP/L
/** ^h wF=
* @param userDAO The userDAO to set. 9! 'qLO
*/ \j
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publicvoid setUserDAO(UserDAO userDAO){ -Q3jK)1
this.userDAO = userDAO; >s0A.7,5
} RcJ.=?I!
bO 8 >w9MF
/* (non-Javadoc) yM* CA,(c
* @see com.adt.service.UserManager#listUser G<1)NT\u
r~f*aD
(org.flyware.util.page.Page) Nr~9] S
*/ z~Zu>Q1u[
public Result listUser(Page page)throws NTq#'O) f
2@7f^be
HibernateException, ObjectNotFoundException { KX8$j$yW
int totalRecords = userDAO.getUserCount(); FPAy.cljJ
if(totalRecords == 0) `FS)i7-o6
throw new ObjectNotFoundException ?\Fo|__
{ #?$p i[
("userNotExist"); >O0z+tj
page = PageUtil.createPage(page, totalRecords); J)R2O{ z
List users = userDAO.getUserByPage(page); _(A9k{
returnnew Result(page, users); 2;8I0BH*'
} sKE7U>mz|
GJTKqr|1O
} (]cM;
$MW-c*5a
=Sjr*)<@j
87&BF)]
YdgDMd-1
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 W=QT-4
S
^5EG;[
询,接下来编写UserDAO的代码: Ug}dw a
3. UserDAO 和 UserDAOImpl: Sr$&]R]^
java代码: D,$!.5OA
j%w}hGW%,
6?B'3~r
/*Created on 2005-7-15*/ Evjvaa^
package com.adt.dao; |[6jf!F
M:[rH
import java.util.List; &P2tzY'
}G{ 'Rb
import org.flyware.util.page.Page; `vbd7i
MxXf.iX&
import net.sf.hibernate.HibernateException; {TmrWFo
n,,hE_
/** #.Q3}[M
* @author Joa ~Qg:_ @@\
*/ |ZJ<J)y
publicinterface UserDAO extends BaseDAO { D./!/>@f
rN$U%\.I
publicList getUserByName(String name)throws W#|30RU.G
$!?tJ@{
HibernateException; 2il)@&^
z2.9l?"rfQ
publicint getUserCount()throws HibernateException; |gV$ks\<
^4G%*-
publicList getUserByPage(Page page)throws Re[x$rw
So6ZNh9
HibernateException; b\Wlpb=QZ
j<*
} c@|!0
U%j
O {hM
\r.{Ru
9`a1xnL
Q4H(JD1f)
java代码: h4iz(*
Y5dt/8Jo
1')_^]
/*Created on 2005-7-15*/ [ClDKswq
package com.adt.dao.impl; 2`Dqu"TWh
H$@5\pP>
import java.util.List; \]:}lVtxS
i(Xz3L#(
import org.flyware.util.page.Page; v0aV>-v
H\>0jr`
import net.sf.hibernate.HibernateException; rd
)_*{
import net.sf.hibernate.Query; G5l?c@o
a+-X\qN
import com.adt.dao.UserDAO; c}-ADr9
5%6{ ePh{
/** V/t/uNm
* @author Joa z~m{'O`
*/ Q
*]d[
public class UserDAOImpl extends BaseDAOHibernateImpl l* ap$1'
_L^(CFE
implements UserDAO { 8*bEsc|
/W|=Or2oR
/* (non-Javadoc) <<SUIY@X
* @see com.adt.dao.UserDAO#getUserByName 1WP(=7$.
S6d&w6
(java.lang.String) qOqU
CRUe:
*/ Xn%ty@8
publicList getUserByName(String name)throws H{d;,KfX
#9/^)^k
HibernateException { 7]8nW!h;
String querySentence = "FROM user in class Y3 V9
7u=R5
com.adt.po.User WHERE user.name=:name"; fO UW{s
Query query = getSession().createQuery -qJ%31Mr#
:lfUVa{HN
(querySentence); mVs<XnA47
query.setParameter("name", name); &i5MRw_]]
return query.list(); sw\O\%^
} W5SCm(QS5
W"meH~[Cp
/* (non-Javadoc) Gi+ZI{)
* @see com.adt.dao.UserDAO#getUserCount() W2`/z)[*>
*/ `;c{E%qeq
publicint getUserCount()throws HibernateException { 2=%R>&]*
int count = 0; )IFFtU~,
String querySentence = "SELECT count(*) FROM au;ZAXM|
!H^e$BA
user in class com.adt.po.User"; T?4I\SG
Query query = getSession().createQuery LkwjEJQf
;1MRBk,
(querySentence); +7V4mF!u
count = ((Integer)query.iterate().next }o:sU^Pwa
>qL-a*w:a
()).intValue(); 2R`dyg
return count; ?= RC?K
} 2mt
S\bAF
MXP3ZN'
/* (non-Javadoc) +
FG Xx
* @see com.adt.dao.UserDAO#getUserByPage K;'s+ZD
s[n*fV']A
(org.flyware.util.page.Page) 1w$X;q"
*/ #*tWhXU
publicList getUserByPage(Page page)throws {aoG60N
L5RBe
HibernateException { #wS/QrRE
String querySentence = "FROM user in class U3tA"X.K
~gi,ky^!
com.adt.po.User"; &_o.:SL|
Query query = getSession().createQuery tj1M1s|a
Nu[0X
(querySentence); DQ`\HY
query.setFirstResult(page.getBeginIndex()) (X?et
&
.setMaxResults(page.getEveryPage()); [B1h0IR
return query.list(); ' 2:HBJ
} (WuJ9
[rO TWN
} ^ fqco9^;
y{#9&ct&
HxnWM\ p
tPz!C&.=
rk)h_zN
至此,一个完整的分页程序完成。前台的只需要调用 Y7GHIzX
7H$wpn
Zln
userManager.listUser(page)即可得到一个Page对象和结果集对象 9k*1_
Mrly(*!U"@
的综合体,而传入的参数page对象则可以由前台传入,如果用 sIz*r Gz
:YUQKy
webwork,甚至可以直接在配置文件中指定。 tg"NWp6
G|+naZ
下面给出一个webwork调用示例: B4RP~^
java代码: /DxeG'O
py%_XL=w,
slH3c:j\
/*Created on 2005-6-17*/ ]1dnp]r
package com.adt.action.user; @#1T-*
vD91t/_+
import java.util.List; Z~Vups#+f
8-geBlCE,
import org.apache.commons.logging.Log; \wb0%>
0
import org.apache.commons.logging.LogFactory; /s[D[:P_
import org.flyware.util.page.Page; 1MYA/l$
TO]7 %aB
import com.adt.bo.Result; zi?G
wh~
import com.adt.service.UserService; F- l!i/
import com.opensymphony.xwork.Action; =67tQx58
\Pt_5.bTs[
/** $/|2d4O:{
* @author Joa >`)IdX
*/ Xo/0lT
publicclass ListUser implementsAction{ p;P
cD
BW{&A&j
privatestaticfinal Log logger = LogFactory.getLog Uy;e5<<
U%4s@{7
(ListUser.class); hMQh?sF/
k3VRa|Y")
private UserService userService; t_NnQ4)=
@mm~i~~KA
private Page page; :&\^r=D
iT,Ya-9"
privateList users; =&x
u"V
met`f0jw
/* 0~=>:^H'`q
* (non-Javadoc) JL:\\JT.
* ,k+F8{Q.
* @see com.opensymphony.xwork.Action#execute() ?:c:D5N
*/ oeF0t'%
publicString execute()throwsException{ ~Blsj9a2
Result result = userService.listUser(page); 9`|~-b
page = result.getPage(); o?((FW5.;
users = result.getContent(); <:!;79T\
return SUCCESS; Bnu5\P
} )^[PW&=W|x
>>R,P
Ow-
/** 9 =zZ,dg
* @return Returns the page. 0s o27k
*/ t(r}jU=qw
public Page getPage(){ k35E,?T
return page; %C=?Xhnv
} /PTk296@
.yN.
/** Xb\de_8!
* @return Returns the users. yl UkVr
*/ <}n"gk1is
publicList getUsers(){ \\v1\
return users; vQsI^p
} Gid6,J
h $2lO^
/** *sYvV,
* @param page v i~NfD@s
* The page to set. Cy2)M(RW
*/ .e1Yd8
publicvoid setPage(Page page){ k^e;V`(
this.page = page; [;, Xp/
} gkMyo`
XyrQJ}WR|
/** i=aK ?^+
* @param users xk@fBa }
* The users to set. W*.6'u)9
*/ s%Ir h;Bs
publicvoid setUsers(List users){ 344E4F"ph
this.users = users; ~pG,|\9
} 0.!!rq,
\
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/** ;^9y#muk
* @param userService ~=i<O&nai
* The userService to set. "e@?^J)
*/ YAJr@v+Ls
publicvoid setUserService(UserService userService){ 6o=Q;Mezl
this.userService = userService; _n=,H
} LY1dEZ-)A
} Jt|W%`X>D
l#^weXSlk
&8M^E/#.^;
ZJ'Tb<fP
; wKsi_``@
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, _}3NLAqg
la{Iqm{i
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 GPLq$^AH
>A
?{cbJ
么只需要: &N:`Rler
java代码: )9s
6(Iu
kcio]@#
,l7',@6Y
<?xml version="1.0"?> PCZ %<>v
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork i;I!Jc_b'
hjx=?
1.0//EN" "http://www.opensymphony.com/xwork/xwork- T)tf!v3v
K</="3
HK
1.0.dtd"> rLx'.:
KGNBzy~9
<xwork> T%[!m5
Z<W`5sop^
<package name="user" extends="webwork- cd:VFjT
ObEp0-^?
interceptors"> WR5W0!'Tf
}/g1s71
<!-- The default interceptor stack name y vo4 .u
~?<VT
k
--> ^gdv:[m
<default-interceptor-ref 7?a!x$-U(
E)]RQ~jY?
name="myDefaultWebStack"/> >@uF ye$
vR?E'K3
<action name="listUser" SnFAv7_
Kl]LnN%A{
class="com.adt.action.user.ListUser"> /\u1q<
<param 8G?OZ47k#
_ Y8jl,J
name="page.everyPage">10</param> J*m~fZ^
<result 8c5%~}kG
|jJ9dTD8/
name="success">/user/user_list.jsp</result> #5=!ew
</action> H0?Vq8I?
#1<Jwt+
</package> .y^T3?}I
\oy8)o/Gb
</xwork> %hV]vm
{<L|Z=&k`
R(W}..U0R"
-,^Z5N#\|
$@@@</VbP
-cL wjI
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 L2{b~`UvP
r9!,cs
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。 <)VNEy'
vCsJnKqK
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 6<m9guv
08F~6e6a8
jV~+=(w)
bm#/ KT_8
Yrmd
hSY
我写的一个用于分页的类,用了泛型了,hoho <-O^ol,fX
eg(1kDMpn
java代码: <jIuVX
{^_K
A? T25<}
package com.intokr.util; v/~Lf i
w*krPaT3
import java.util.List; N`rz>6,k1
0W!S.]^1
/** $i"IOp
* 用于分页的类<br> h}yfL@
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ;I!Vba
* Cm~z0c|T
* @version 0.01 9Je+|+s]
* @author cheng zx`(ojfu
*/ 6![}Jvu>
public class Paginator<E> { QM4O|x[
privateint count = 0; // 总记录数 @nxpcHj
privateint p = 1; // 页编号 )POU58$
privateint num = 20; // 每页的记录数 U}^`R,C
privateList<E> results = null; // 结果 H.#zbKj
!A'3Mw\Nm
/** f=T&$tZ<
* 结果总数 ?C* }NM
*/ wjfc9z
publicint getCount(){ VX]Ud\(
return count; -E>LB\[t)
} `tH:oP0=
`=19iAp.
publicvoid setCount(int count){ zr^"zcfz&
this.count = count; <P0&!yN
} ?eOw8Rom
Fb<fQIa
/** DQ9}('^
* 本结果所在的页码,从1开始 z(Q 5?+P
* IA^*?,AZy
* @return Returns the pageNo. ]@
N::!m
*/ &*9' 0
publicint getP(){ M {Hy=:K+
return p; JV@b(x`
} \fJ _,
J>Bc-%.Q
/** *IIuGtS
* if(p<=0) p=1 &2,^CG
* Hd?#^X
* @param p -$ha@bCWO
*/ QR{>]I
publicvoid setP(int p){ ,| ~Pa
if(p <= 0) :YM1p&|fS
p = 1; "P8(R
this.p = p; m
e2$ R>@
} CMC9%uq
$mcq/W
/** _E8doV
* 每页记录数量 h1Logm+m
*/ O>[B"mMt
publicint getNum(){ Z!*k 0<Z
return num; rH9[x8e
} Z=zD~ka
?$~5ti#\
/** Q&8epO |J
* if(num<1) num=1 5;X3{$y
*/ qv)%)n
publicvoid setNum(int num){ g
[c^7
if(num < 1) |C}= 1
num = 1; 8RjFp2)W
this.num = num; b/obHB+:
} DMiB \o
B~47mw&b
/** A+ LX37B
* 获得总页数 h]DzX8r}
*/ -~ H?R
publicint getPageNum(){ /5m ~t.Z9M
return(count - 1) / num + 1; ]BaK8mPl
} |SuN3B4e
l09SWug
/** <~n%=^knE
* 获得本页的开始编号,为 (p-1)*num+1 M s Q=1
*/ +%?\#E QJ
publicint getStart(){ Y}
crE/
return(p - 1) * num + 1; YSux#*#H
} !XQ)>T^G5
*&tv(+P
/** T4h&ly5
f
* @return Returns the results. oD=+
*/ lD6PKZ\RIj
publicList<E> getResults(){ mO&zE;/[
return results; n7pjj
} ]:.9:RmEV
x\5v^$
public void setResults(List<E> results){ %s ">:
this.results = results; M"5S
} !NTt'4/F{
PE<(eIr
public String toString(){ yeIcQ%
StringBuilder buff = new StringBuilder li9>zjz
S)x5.vo^
(); MR/gLm(8(
buff.append("{"); d'[]
buff.append("count:").append(count); ')>D*e
buff.append(",p:").append(p); _zDf8hy
buff.append(",nump:").append(num); Xk }\-&C7
buff.append(",results:").append Y@limkN:
lK3{~\J-
(results); 9YY*)5eyD
buff.append("}"); =i>i,>bv
return buff.toString(); gXe`G(w
} ?u~?:a@K
0X4I-xx#
} H0-v^H>^
La
r9}nx0
SHRn$<