Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 I9;,qd%<T
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 L4-v'Z;
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来
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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 hTVA^j(w
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分页支持类: e.jbFSnA
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java代码: mJ L=H
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package com.javaeye.common.util; %uy5la
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import java.util.List; 6#DDMP8;I
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publicclass PaginationSupport { #1oyRD-
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publicfinalstaticint PAGESIZE = 30; ErXzKf
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privateint pageSize = PAGESIZE; -oR P ZtW
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privateList items; k~=_]sLn
*'jI>^o
privateint totalCount; 5VR=D\j
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privateint[] indexes = newint[0]; GPs//
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privateint startIndex = 0; A{Dy3tm=
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public PaginationSupport(List items, int @pkQ2OM
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totalCount){ @[. 0,
setPageSize(PAGESIZE); T_/ n#e
setTotalCount(totalCount); 0l+[[ZTV
setItems(items); * faG0le
setStartIndex(0); <Po$|$_~
} ATscP hk
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public PaginationSupport(List items, int KO3X)D<3
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totalCount, int startIndex){ AMf{E
setPageSize(PAGESIZE); Jwt_d}ns
setTotalCount(totalCount); j9^V)\6)
setItems(items); N83c+vs%c
setStartIndex(startIndex); ;G|#i?JJ
} yeqHeZ
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public PaginationSupport(List items, int 5~GH*!h%;
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totalCount, int pageSize, int startIndex){ "cD MFu
setPageSize(pageSize); 5e}adHjM
setTotalCount(totalCount); V18A|]k
setItems(items); ^LAnR>mz^r
setStartIndex(startIndex); &Xh_`*]ox
} &.1qixXIr
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publicList getItems(){ ^Cy=L]
return items; <kOdd)X
} PQJw"[N/YM
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publicvoid setItems(List items){ ;(r,;S_`0
this.items = items; 5u=>~yK+
} X([p0W
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publicint getPageSize(){ kr>4%Ndm7
return pageSize; :e rfs}I
} V
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publicvoid setPageSize(int pageSize){ K;j0cxl
this.pageSize = pageSize; 45A|KaVpg
} gJBw6'Z
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publicint getTotalCount(){ "el}9OitC
return totalCount; ~1:_wni
} ^2C
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publicvoid setTotalCount(int totalCount){ _?v&\j
if(totalCount > 0){ !q!5D`
this.totalCount = totalCount; tE WolO[\
int count = totalCount / 7A"v:e
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pageSize; <%?!3 n*
if(totalCount % pageSize > 0) G3dA`3
count++; 4t,f$zk
indexes = newint[count]; _qa9wK/
for(int i = 0; i < count; i++){ Z;~ 7L*|
indexes = pageSize * /(8"9Sfm
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i; #5%ipWPHb
} YHzP/&0
}else{ (lg~}Jwq
this.totalCount = 0; ~@mNR^W-W
} g&I|@$\
} suHisc*
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publicint[] getIndexes(){ %>-?oor
return indexes; H5Bh?mw2
} 46U*70
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publicvoid setIndexes(int[] indexes){ V 5D8z
this.indexes = indexes; B&m6N,
} . ZP$,
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publicint getStartIndex(){ -% \LW1
return startIndex; 0K4A0s_R`
} ^h!}jvqE
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publicvoid setStartIndex(int startIndex){ mJZB@m u?
if(totalCount <= 0) ),J6:O&
this.startIndex = 0; `Wd4d2aLG
elseif(startIndex >= totalCount) ~9Qd83`UH
this.startIndex = indexes M>d^.n
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[indexes.length - 1]; zZ 94_8b
elseif(startIndex < 0) 08+\fT [
this.startIndex = 0; C#n.hgo>I
else{ tMH2
this.startIndex = indexes SP"t2LTP
*Hz]<b?
[startIndex / pageSize]; U".5x~UC
} upnX7as
} ;FJFr*PM
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publicint getNextIndex(){ CbwQbJ/v7
int nextIndex = getStartIndex() + {r%T_BfY
'^`iF,rg
pageSize; QXW>}GdKZ
if(nextIndex >= totalCount) OwPXQ 3S
return getStartIndex(); Jl<pWjkZZ
else w=FU:q/
return nextIndex; ^l<!:SS
} 0#CmB4!<O
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publicint getPreviousIndex(){ $WXO1o(O
int previousIndex = getStartIndex() - 8[;AFm ?,`
2!R+5^Iy
pageSize; 2~R%_r+<
if(previousIndex < 0) 5Q\ hd*+g
return0; (TU/EU5
else 3L36
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return previousIndex; aNBwb9X
} B=~uJUr
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} .F N
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抽象业务类 wI;sZJc
java代码: qh+&Z x~
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/** Tgl >
* Created on 2005-7-12 R90#T6^
*/ j2%fAs<
package com.javaeye.common.business; @}2EEo#
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import java.io.Serializable; sX-@
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import java.util.List; c
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import org.hibernate.Criteria; Y<V$3h
import org.hibernate.HibernateException; M:dH>
import org.hibernate.Session; f!H/X%F
import org.hibernate.criterion.DetachedCriteria; H%>^_:h
import org.hibernate.criterion.Projections; B<ue}t
import Sp2DpGs~
3 .K #,
org.springframework.orm.hibernate3.HibernateCallback; B#?rW*yEe
import 'S|7<<>4k
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org.springframework.orm.hibernate3.support.HibernateDaoS M2\c0^R
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upport; ^#IE
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import com.javaeye.common.util.PaginationSupport; Z1Qv>@u
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public abstract class AbstractManager extends vCXmu_S4^>
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HibernateDaoSupport { j^WYMr,
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privateboolean cacheQueries = false; pXvys]@
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privateString queryCacheRegion; t fD7!N{
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publicvoid setCacheQueries(boolean _zJ /z
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cacheQueries){ nM ?Nf}
this.cacheQueries = cacheQueries; Lz!JLiMEET
} @|5B}%!
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publicvoid setQueryCacheRegion(String ?^2nrh,n+
q!W=U8`
queryCacheRegion){ 81C;D`!K
this.queryCacheRegion = M6bM`wHH>
{3.n!7+
queryCacheRegion; CRD=7\0(D+
} Ql%B=vgKL
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publicvoid save(finalObject entity){ z~==7:Os
getHibernateTemplate().save(entity); D/JSIDd
} }+Q4s]
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publicvoid persist(finalObject entity){ C"$~w3A k
getHibernateTemplate().save(entity); *l;S"}b*,_
} JU.!<
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publicvoid update(finalObject entity){ 00{a}@n
getHibernateTemplate().update(entity); 2r;h">
} ca3SE^
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publicvoid delete(finalObject entity){ u!&T}i:
getHibernateTemplate().delete(entity); RRpY%-8M
} ^G2M4+W|
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publicObject load(finalClass entity, H
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finalSerializable id){ ];"40 /X
return getHibernateTemplate().load o"FR%%
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(entity, id); '7/F]S0K
} N{~P}Sw
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publicObject get(finalClass entity, }+bo?~2E&
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finalSerializable id){ wy
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return getHibernateTemplate().get ^<;CIXo
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(entity, id); aSu^
} LnKgT1
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publicList findAll(finalClass entity){ !h|,wq]k
return getHibernateTemplate().find("from ,Q3OQ[Nmh
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" + entity.getName()); ;']u}Nh
} @x!,iT
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publicList findByNamedQuery(finalString ExSM=
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namedQuery){ l qwy5#
return getHibernateTemplate +/l@ou'
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().findByNamedQuery(namedQuery); lS#:u-k
} &M@c50&%
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publicList findByNamedQuery(finalString query, ?|/K(}
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finalObject parameter){ rMHh!)^#W
return getHibernateTemplate C:}1r
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().findByNamedQuery(query, parameter); RgUQ:
} t72u%M6
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publicList findByNamedQuery(finalString query, KvEv0L<ky
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finalObject[] parameters){ iw=e"6V
return getHibernateTemplate XzSl"U PYH
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().findByNamedQuery(query, parameters); U,Uy0s2r
} dNNXMQ0"
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publicList find(finalString query){ \#LDX,=
return getHibernateTemplate().find 2G$px
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(query); 5>+@.hPX
} 'W4B
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publicList find(finalString query, finalObject t&EizH$
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parameter){ -j]c(Q MA]
return getHibernateTemplate().find tpEy-"D&
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(query, parameter); (]T[n={Y
} S{N4[U?V>
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public PaginationSupport findPageByCriteria :$k1I-^R
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(final DetachedCriteria detachedCriteria){ Z37Dv;&ZD
return findPageByCriteria dor1(@no|
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); G+Z ,ic
} s>I]_W)Pt
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public PaginationSupport findPageByCriteria fS/:OnH
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(final DetachedCriteria detachedCriteria, finalint ymqv@Byi8A
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startIndex){ NK/y,f6
return findPageByCriteria #::+# G
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fg
(detachedCriteria, PaginationSupport.PAGESIZE, u"V,/1++\
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startIndex); " "m-5PGYo
} 9
@ <
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public PaginationSupport findPageByCriteria gC(S(osF
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(final DetachedCriteria detachedCriteria, finalint }T(=tfv@
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pageSize, %(p9AE
finalint startIndex){ *EvW: <
return(PaginationSupport) )mf|3/o
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getHibernateTemplate().execute(new HibernateCallback(){ VgIk '.
publicObject doInHibernate GiX3c^V"1
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(Session session)throws HibernateException { R*2N\2
Criteria criteria = 3IQI={:k|D
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detachedCriteria.getExecutableCriteria(session); ?!U.o1
int totalCount = s|A[HQUtJ
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((Integer) criteria.setProjection(Projections.rowCount }A@:JR+|
*cCx]C.~
()).uniqueResult()).intValue(); AVw oOvJ
criteria.setProjection i0/QfB%O
gBhX=2%
(null); GvG8s6IZ
List items = L~{(9J'(
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criteria.setFirstResult(startIndex).setMaxResults hBnUpYec
g[1>|Ax`'
(pageSize).list(); B>:U
PaginationSupport ps = i6k6l%
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new PaginationSupport(items, totalCount, pageSize, \ui'~n_t]
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startIndex); RHn3\N
return ps; M0xhcU_
} G .<0^q,
}, true); WwTl|wgvyI
} M>m!\bb%.
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public List findAllByCriteria(final u9KT_`
)
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DetachedCriteria detachedCriteria){ ^gx~{9`RR
return(List) getHibernateTemplate D
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().execute(new HibernateCallback(){ x$` lQ%
publicObject doInHibernate $Z]@N
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[ !#Dba#
(Session session)throws HibernateException { /"st
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Criteria criteria = jQm~F`z
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detachedCriteria.getExecutableCriteria(session); ~Yg)8
return criteria.list(); +@!\3a4!
} \RR`
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}, true); BWxJ1ENM
} "1^tVw|
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public int getCountByCriteria(final 5j.@)XXe
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DetachedCriteria detachedCriteria){ "Hz%0zP&
Integer count = (Integer) kP[fhOpn
}"WovU{*s
getHibernateTemplate().execute(new HibernateCallback(){ (_ :82@c
publicObject doInHibernate
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(Session session)throws HibernateException { %La7);SeY
Criteria criteria = 7glf?oE
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detachedCriteria.getExecutableCriteria(session); pXl qE,
return CKZEX*mPC
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criteria.setProjection(Projections.rowCount oY0b8=[
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()).uniqueResult(); 1G12FV>M
} 2HBey
}, true); aW dI
return count.intValue(); UW8yu.`?
} u;H^4}
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} !y~nsy:&7x
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用户在web层构造查询条件detachedCriteria,和可选的 VT4>6u}
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 H/M]YUs/3
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PaginationSupport的实例ps。 5<`83;R9
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ps.getItems()得到已分页好的结果集 /v<Gt%3X
ps.getIndexes()得到分页索引的数组 (n.IK/:
ps.getTotalCount()得到总结果数 iOhX\@&
ps.getStartIndex()当前分页索引 Q`'cxx
ps.getNextIndex()下一页索引 3=oxT6"k
ps.getPreviousIndex()上一页索引 fA<os+*9i
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 9#1?Pt^{<
s 7wA3|9
,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 HU/4K7e`
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一下代码重构了。 {aV,h@>
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我把原本我的做法也提供出来供大家讨论吧: $Bc3| `K1v
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首先,为了实现分页查询,我封装了一个Page类: b|k^
java代码: .YvIVQ
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/*Created on 2005-4-14*/ X,G"#j^
package org.flyware.util.page; ^4,LIIUj
!mqIq}h
/** P(I%9
* @author Joa
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* vs+aUT C\
*/ ^CQp5k p]
publicclass Page { `5oXf
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/** imply if the page has previous page */ ?o6#i 3k#'
privateboolean hasPrePage; 2 f%+1uU
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/** imply if the page has next page */
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privateboolean hasNextPage; ucz~y!4L{
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/** the number of every page */ A =Z$H2
privateint everyPage; ztHx)
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/** the total page number */ 0/|Ax-dK
privateint totalPage; sl@>GbnS
qhTVsZ:{C
/** the number of current page */ XABP}|aWK
privateint currentPage; VuTTWBx
HbPn<x^7
/** the begin index of the records by the current 6hR `sE
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query */ *PFQ
privateint beginIndex; %zY5'$v `
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P~lU`.X}
/** The default constructor */ `S4*~Xx
public Page(){ 3:#6/@wQ
sqV~Dw
} hg<[@Q%$o
-CFy
/** construct the page by everyPage ; }T+ImjA
* @param everyPage {0+WVZ4u
* */ pQc-}o"
public Page(int everyPage){ fyT|xI`iD
this.everyPage = everyPage; JJg;X :p
} M,kO7g
$.w$x1
/** The whole constructor */ C,mfA%63
public Page(boolean hasPrePage, boolean hasNextPage, OJA_OqVp$K
ojm IEzsz
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int everyPage, int totalPage, Fkpaou
int currentPage, int beginIndex){ w8$>
2
this.hasPrePage = hasPrePage; * Wp?0CP
this.hasNextPage = hasNextPage; \I}EWI
this.everyPage = everyPage; (xTGt",_Jo
this.totalPage = totalPage; {fV$\^c
this.currentPage = currentPage; 0k5 uqGLXe
this.beginIndex = beginIndex; k$f2i,7'
} (dyY@={q
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/** 9I<~t@q5e@
* @return }!Pty25j
* Returns the beginIndex. umnQ$y
0
*/ =w`uZ;l$Q
publicint getBeginIndex(){ w 2U302TZ
return beginIndex; Gl|n }wo$
} B6Ajcfy
\k"Ct zoX
/** A*/8j\{n
* @param beginIndex LxWd_B
* The beginIndex to set. XHJ`C\xR
*/ YIgHLM(
publicvoid setBeginIndex(int beginIndex){ \ %MsG
this.beginIndex = beginIndex; [YODyf}M>\
} :O&jm.2m
[iO8R-N8d
/** iV#A-9
* @return [\h?mlG?
* Returns the currentPage. PP!-*~F0Jr
*/ AX1!<K
publicint getCurrentPage(){ ?fC9)s
return currentPage; .Oc j|A6
} (.Ak*
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/** *pnaj\
* @param currentPage Uzrf,I[
* The currentPage to set. w8 UUeF
*/ t18j2P>`
publicvoid setCurrentPage(int currentPage){ EVaHb;
this.currentPage = currentPage; K*,,j\Q.
} LCj3{>{/=
/5L\:eX%
/** ?mK&Slh.
* @return 3pW4Ul@e
* Returns the everyPage. H-u
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*/ d2gYBqag
publicint getEveryPage(){ rMjb,2*rC7
return everyPage; kF,ME5%
} )Qe]!$tqfD
I
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/** 5cU:wc
* @param everyPage =6=:OId
* The everyPage to set. 's5rl
*/ ~QPTs1Vk8
publicvoid setEveryPage(int everyPage){ BB69U
this.everyPage = everyPage; -}!mi V
} OX]P;#4tU
^=5y;
/** s]kzXzRC?
* @return c[ 0`8s!
* Returns the hasNextPage. +U_1B%e(%
*/ gCG#?f
publicboolean getHasNextPage(){ 0 } &/n>F
return hasNextPage; bE2O[B
} R'>@ja*
\SO)|M>. a
/** Lr8|S
* @param hasNextPage (>x05nh
* The hasNextPage to set. a:HN#P)12
*/ mDbTOtD
publicvoid setHasNextPage(boolean hasNextPage){ z9OpxW@Ou
this.hasNextPage = hasNextPage; >!']w{G
} z^&$6c_
ZbdGI@
/** >D~8iuy]8.
* @return |%F4`gz8KP
* Returns the hasPrePage. &^HVuYa.0
*/ 0pEM0M
publicboolean getHasPrePage(){ (&v|,.c^)1
return hasPrePage; ly6zz|c5
} F|5Au>t
oCI\yp@a
/** ,5}w]6bCr
* @param hasPrePage |Z2"pV
* The hasPrePage to set. #Cu$y8~as
*/ 1>L'F8"
publicvoid setHasPrePage(boolean hasPrePage){ #Y'b?&b
this.hasPrePage = hasPrePage; h qjjd-S0
} )b2O!p
tAJ}36aG
/** Q#qfuwz
* @return Returns the totalPage. u'_}4qhCC;
* }Kp<w,
*/ zYY]+)k?
publicint getTotalPage(){ x
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return totalPage; Mb\(52`)Q
} ,>kVVpu
Ng
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/** ty[p5%L1
* @param totalPage } -;)G~h/"
* The totalPage to set. a`f@&A`z
*/ g%[:wjV;
publicvoid setTotalPage(int totalPage){ /w5*R5B{
this.totalPage = totalPage; Qb/:E}h]$
} 8uH8)
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} 4\v &8">LL
AgSAjBP
62 _k`)k
=*lBJ-L
.f-=gZ* *
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 eh]syeKBj
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个PageUtil,负责对Page对象进行构造: 5<v1v&
java代码: ^5TVm>F@3
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/*Created on 2005-4-14*/ ~AX~z)
package org.flyware.util.page; 6z6\xkr
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import org.apache.commons.logging.Log; ?H@<8Ra=3
import org.apache.commons.logging.LogFactory; s9nPxC&A
ysIhUpd
/** aHpZhR|f$
* @author Joa ZBY2,%nAo
* WfG +_iP?
*/ @Bhcb.kbq
publicclass PageUtil { },JJ!3
*kqC^2t
privatestaticfinal Log logger = LogFactory.getLog t? 6 et1~
>jIn&s!}
(PageUtil.class); _&S#;ni\c
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/** Rky]F+J
* Use the origin page to create a new page V8B4e4F
* @param page d*gv.mE
* @param totalRecords <n#X~}i)
* @return -wg}X-'z0
*/ vMEN14;yH_
publicstatic Page createPage(Page page, int /(5"c>
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totalRecords){ @$%GszyQ'
return createPage(page.getEveryPage(), y<Xu65
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page.getCurrentPage(), totalRecords); x:!s+q`
s
} 1@KiP`DA
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/** F/>\uzu
* the basic page utils not including exception |%XTy7^a
SiX<tj#HH\
handler ug2W{D
* @param everyPage ycc G>%>r
* @param currentPage LAxN?ok9gD
* @param totalRecords H2Wlgt
* @return page 8^j~uH
*/ j+ -r(lZ
publicstatic Page createPage(int everyPage, int J({D~
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currentPage, int totalRecords){ /R=MX>JA;
everyPage = getEveryPage(everyPage); r W[;3yMf
currentPage = getCurrentPage(currentPage); `DgK$ QM
int beginIndex = getBeginIndex(everyPage, mi Q*enZi
=NC??e {
currentPage); *4`5&) `
int totalPage = getTotalPage(everyPage, AK&>3D
J$1H3#VVG
totalRecords); \b(&-=(
boolean hasNextPage = hasNextPage(currentPage, ~KMah
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totalPage); j`RG Moq
boolean hasPrePage = hasPrePage(currentPage); Z8xB
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returnnew Page(hasPrePage, hasNextPage, =ejU(1 g
everyPage, totalPage, Yr-SlO>
currentPage, G|1.qHP[F
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beginIndex); 4{zy)GE|W
} |3,WiK='
j;coP ehB
privatestaticint getEveryPage(int everyPage){ ..u{v}4&
return everyPage == 0 ? 10 : everyPage; 9_:"`)]3B
} r@zT!.sc!
MukJ^h*V
privatestaticint getCurrentPage(int currentPage){ _(h=@cv
return currentPage == 0 ? 1 : currentPage; A[;deHg=
} ;NRh0)%|o
; o_0~l=-/
privatestaticint getBeginIndex(int everyPage, int Hm'"I!jyO
%w65)BFQ
currentPage){ L>sLb(2\i
return(currentPage - 1) * everyPage; <6 Rec^QF
} ANu>*
[h;I)ug[o(
privatestaticint getTotalPage(int everyPage, int \~%+)a%%
.@OQ$D <
totalRecords){ Pa3-0dUr
int totalPage = 0; 2'S&%UyP
pPRX#3
if(totalRecords % everyPage == 0) +8//mrL_/
totalPage = totalRecords / everyPage; ^{MqJ\S7H
else JnBc@qnP6
totalPage = totalRecords / everyPage + 1 ; )x/#sW%)
Zc~7R`v7}
return totalPage; 8~C}0H
} }bS1M
Gr2}N"X=
privatestaticboolean hasPrePage(int currentPage){ Ie^Ed`
return currentPage == 1 ? false : true; > U?\WgE$
} a4^hC[a
[6mK<A,/
privatestaticboolean hasNextPage(int currentPage, rueaP
"{D/a7]lC
int totalPage){ Y`ip.Nx
return currentPage == totalPage || totalPage == 6L8nw+mEK
N+c|0
0 ? false : true; EZB0qZIp
} ~&)\8@2
:[n~(~7?
!FP ]
} (v/L
,Lp"Ia
}VJ>}i*
,g7O
(]'wQ4iQ
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。 tB>!1}v
z]8Mv(eL
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 s|<n7 =J
Q;3`T7
做法如下: fW2NYQP$:
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 x!GDS>
g3kbsi7_:
的信息,和一个结果集List: Gpxp8[ {
java代码: U!|)M
lot`6]
@
,X/Wf
/*Created on 2005-6-13*/ RG45S0Ygj
package com.adt.bo; lF(v<drkB
}XBF#BN
import java.util.List; Qt4mg?X/
qWr=Oiu
import org.flyware.util.page.Page; _)5E=
?fy37m(M}
/** S&UP;oc
* @author Joa E6~VHQa2?
*/ }~@/r5Zl
publicclass Result { [ ft6xI
akbB=:M,x
private Page page; 2K>1,[ C'Z
n`Pl:L*kG
private List content; Q.B)?w m
1r>]XhRFZ
/** ~fkcal1@
* The default constructor q#AEu
xI1
*/ M(+Pd_c6
public Result(){ 8+w*,Ry`
super(); Nxe1^F33
} PzKTEYJL
u|IS7>Sm
/** `"CA$Se8
* The constructor using fields GZaB z#U
* xbCR4upS
* @param page ||X3g"2W9
* @param content kBk>1jn"
*/
s*gqKQ;
public Result(Page page, List content){ HQ"T>xb
this.page = page; 'm*W<
this.content = content; pl
r@
} Gz{%Z$A~o
M4)U
[v
/** O)&W0`VY
* @return Returns the content. lGYW[0dy
*/ ddN(L`nd
publicList getContent(){ VCc=dME
return content; ^9,^BHlC0
} /A0_#g:2*#
iqB5h|
`
/** feyc
* @return Returns the page. o
A2oX
*/ *D%w r'!>
public Page getPage(){ BmpAH}%T
return page; "v?F4&\ 8
} 0^>,
H}GGUE&c*
/** #:BkDidt2v
* @param content \12G,tBH
* The content to set. {?lndBP<
*/ z**2-4 z
public void setContent(List content){ (mP{A(kwJ
this.content = content; \ejHM}w3,
} tm5{h{AM
rVP\F{Q4Tr
/** 0e0)1;t\
* @param page H'#06zP>5
* The page to set. AcuZ?LYzK
*/ ,(q]
$eOZ
publicvoid setPage(Page page){ grE(8M
this.page = page; 0#TL$?=|
} sTP\}
} L~/,;PHN
f$:Y'$Z1
5B)&;[
l9uocP:D
3 orZBT
2. 编写业务逻辑接口,并实现它(UserManager, I]d-WTd
!{+CzUo@
UserManagerImpl) 'MW%\W;
java代码: M *w{PjU
( gg )?
AJB
NM
/*Created on 2005-7-15*/ sm'_0EUg
package com.adt.service; j=T8b
bDl#806P L
import net.sf.hibernate.HibernateException; %C`P7&8m=O
N,lr~6)
import org.flyware.util.page.Page; C[%Qg=<
55s5(]`d
import com.adt.bo.Result; P]n0L4c
!y XGAg,
/** ,u>LAo0
* @author Joa ORrZu$n`p
*/ 3);P!W4>
publicinterface UserManager { Mrgj*|
D|(\5]:R
public Result listUser(Page page)throws (<>??(VM
|oU I2<"
HibernateException; kiJ=C2'&
&!4E3&+2m
} @.E9ml
c6 &k?Puy
<vWP_yy
v3cMPN
KwHN c\\
java代码: J:W+'x`@
n[e C
ynM:]*~K
/*Created on 2005-7-15*/ )B
$Q
package com.adt.service.impl; QWa@?BO2p
W8bp3JX"
import java.util.List; DgcS@N
%J2Ad
import net.sf.hibernate.HibernateException; b?OA |JqX
>k`qPpf&
import org.flyware.util.page.Page; ,Tar?&C:
import org.flyware.util.page.PageUtil; \&+Y;:6
}*rS g .
import com.adt.bo.Result; ]wDqdD y7S
import com.adt.dao.UserDAO; bvh#Q_
import com.adt.exception.ObjectNotFoundException; wbF`wi?
import com.adt.service.UserManager; ``<#F3
!%M,x~H
/** 0,~s0]h0V
* @author Joa PcA^ jBgGl
*/ EpG9t9S9
publicclass UserManagerImpl implements UserManager { 8/j|=Q,5
` Ny(S2
private UserDAO userDAO; ^@8XJ[C,_
`},:dDHI
/** dakHH@Q
* @param userDAO The userDAO to set. ;UgwV/d
*/ V
H`_
publicvoid setUserDAO(UserDAO userDAO){
9;%$
this.userDAO = userDAO; i[9gcL"
} @,1_CqV
@`
Pn<_L
/* (non-Javadoc) U[3w9
* @see com.adt.service.UserManager#listUser =(hBgNH
mK$E&,OkA
(org.flyware.util.page.Page) _4)
t
*/ KRlJKd{
public Result listUser(Page page)throws 8tSY|ME
y
_ap T<P
HibernateException, ObjectNotFoundException { d+)L K~
int totalRecords = userDAO.getUserCount(); 8K9HFT@yV
if(totalRecords == 0) ssQ1u.x9
throw new ObjectNotFoundException 3<<wHK;)
*:d``L
("userNotExist"); r3?8nQ$
page = PageUtil.createPage(page, totalRecords); +|bmUm<2
List users = userDAO.getUserByPage(page); `^{G`es
returnnew Result(page, users); PTe$dPB
} ~SBW`=aP}
9;XbyA]
} MVzj7~+
p_BG#dRM
^PFiO 12
KB~1]cYMp
,d/$!Yf
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 {@L{l1|0
gQik>gFr
询,接下来编写UserDAO的代码: `:Wyw<^
3. UserDAO 和 UserDAOImpl: !NNPg?Y
java代码: z =H?@z
`f}ZAX
Y_faqmZ9]
/*Created on 2005-7-15*/ XelFGT E
package com.adt.dao; W (TTsnnx
.(Ux1.0C
import java.util.List; >.P*lT
qU6!vgM&
import org.flyware.util.page.Page; gmu.8
An(gHi;1$
import net.sf.hibernate.HibernateException; v,ecNuy*d
@>U9CL"
/** wH@<0lw`<
* @author Joa Z\C"/j<y
*/ jN{k }
publicinterface UserDAO extends BaseDAO { i:
-IZL\
_3wJ;cn.
publicList getUserByName(String name)throws qDswFs(
!-qk1+<h
HibernateException; o"RE4s\G~r
_6.@^\;
publicint getUserCount()throws HibernateException; V[#lFl).
&
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publicList getUserByPage(Page page)throws K|1^?#n
ta4<d)nB
HibernateException; mg;AcAS.o,
i\eykYc,
} XAFTLNV>
g%[Ruugu
n<$I, IRE
nMbV{h ,
#5I "M WA
java代码: r#~6FpFVK^
`4p9K
vA{[F7
/*Created on 2005-7-15*/ u1kbWbHu(
package com.adt.dao.impl; hP#&]W3:
xO@OkCue
import java.util.List; p.IfJ|
gR>#LM&dG
import org.flyware.util.page.Page; 6%xl}z]o
C]XDDr
import net.sf.hibernate.HibernateException; ~gDtj&F
import net.sf.hibernate.Query; =f p(hX"
y@z#Jw<
import com.adt.dao.UserDAO; y|mR'{$I
Q&\k"X 1
/** v>P){VT
* @author Joa 1wM
p3
*/ ixkg,
public class UserDAOImpl extends BaseDAOHibernateImpl Zn!SHj
#WG(V%f]
implements UserDAO { `'QPe42
t8[:}[Jx
/* (non-Javadoc) [6tQv<}^
* @see com.adt.dao.UserDAO#getUserByName @'y"D
$7*Ml)H!9
(java.lang.String) X[[=YCi0
*/ m1hf[cg
publicList getUserByName(String name)throws *\>2DUu\`
, $=V
HibernateException { ,5*4%*n\
String querySentence = "FROM user in class j?(QieBH
fe$WR~
com.adt.po.User WHERE user.name=:name"; (TQXG^n$gY
Query query = getSession().createQuery 'mM5l*{
f<'C<xnf
(querySentence); G7<X l}
query.setParameter("name", name); kgu+q\?
return query.list(); .PxM
#;i2
} _Owz%
nNKL{Hp
/* (non-Javadoc) 3^a"$VW1
* @see com.adt.dao.UserDAO#getUserCount() L$Q+R'
*/ 1 &<@(S<
publicint getUserCount()throws HibernateException { VQ;=-95P
int count = 0; Xz@>sY>Jc
String querySentence = "SELECT count(*) FROM "8I4]'
T_dd7Ym'8
user in class com.adt.po.User"; 8K/lpqw
Query query = getSession().createQuery D.e*IP1R
{m?x},
(querySentence); $} Myj'`r
count = ((Integer)query.iterate().next Z-?9F`}
3PGyqt(
()).intValue(); (!(bysi9
return count; F*=RP$sj
} B+LNDnjO]
1d"P) 3dQ
/* (non-Javadoc) Y4O L 82Y
* @see com.adt.dao.UserDAO#getUserByPage jj2UUQ|
4Ojw&ys@V
(org.flyware.util.page.Page) 5 $J
*/ @6SSk=9_S
publicList getUserByPage(Page page)throws ik*_,51Zj
,L;vN6~
HibernateException { ^q`*!B9@
String querySentence = "FROM user in class Vmc)or*#
ZJ(!jc$"*%
com.adt.po.User"; aBnbu
vp
Query query = getSession().createQuery 11sW$@xs
9
$\
'\@3o
(querySentence); G;;~xfE'
query.setFirstResult(page.getBeginIndex()) _u>>+6,p
.setMaxResults(page.getEveryPage()); :6+~"7T
return query.list(); u"jnEKN0y
} M=A9ax
%U7B0-
} 1c!},O
~}*;Ko\
0Pk-FSY|f
Izu.I_$4
%K7}yy&9C
至此,一个完整的分页程序完成。前台的只需要调用 cw.7YiU
(% P=#vZ
userManager.listUser(page)即可得到一个Page对象和结果集对象 Ev16xL8B
$5r,Q{;$
的综合体,而传入的参数page对象则可以由前台传入,如果用 O@rb4(
pg)g&ifKl
webwork,甚至可以直接在配置文件中指定。 s_LSsyqo
A\)X&vR[6
下面给出一个webwork调用示例: 3#[I_
java代码: MV}]i@V
`%3p.~>
6pR#z@,
/*Created on 2005-6-17*/ aw1J#5j`n
package com.adt.action.user; M'iKk[Hjfx
X;:xGZ-oY
import java.util.List; +kL(lBv'
dk/*%a
+
import org.apache.commons.logging.Log; N}G(pq}
import org.apache.commons.logging.LogFactory; }o-P
import org.flyware.util.page.Page; 8B/9{8
/GUuu
import com.adt.bo.Result; w)n]}k
import com.adt.service.UserService; 8A .7=C' z
import com.opensymphony.xwork.Action; 'wrpW#
tqCg<NH.!m
/** [@Y q^.6t
* @author Joa C6~dN&q
*/ /p0LtUMu
publicclass ListUser implementsAction{ I:<R@V<~#
m=B0!Z1xx
privatestaticfinal Log logger = LogFactory.getLog !++62Lf
8zWPb
(ListUser.class); [Gy'0P(EQ
~*[4DQ[\
private UserService userService; 5FI>T=QF
iGLYM-
private Page page; c&-$?f
r
"lf3hWGw
privateList users; _ZBR<{
.~
lt+M9
/* qI*1+R}
* (non-Javadoc) a HL '(<
* -<]_:Kf{;&
* @see com.opensymphony.xwork.Action#execute() Q0\5j<'e
*/ RJ4mlW
publicString execute()throwsException{ T9-a
uK0d
Result result = userService.listUser(page); yW?%c#9D
page = result.getPage(); bU`yymf{L
users = result.getContent(); |9]K:A
return SUCCESS;
Tpx,41(k
} 98'XSL|
%0]b5u
/** [_b='/8
* @return Returns the page. g}QTZT8
*/ I>Fh*2
public Page getPage(){ a&Du5(r;!
return page; P%HyIODS
} C&N4<2b
C)p<M H<
/** v=1S
* @return Returns the users. i!x5T%x_
*/ n@[</E(
publicList getUsers(){ G;c0
return users; 6RQCKN)
} F{~r7y;0
@ ]wem
/** ULmdt
* @param page {0WIDD
* The page to set. <JM%Kn )
*/ ^Jl!WH=20}
publicvoid setPage(Page page){ T)f_W
this.page = page; t0d '>
} {}&f\6OI%
Z;SG<
/** ef:$1VIBda
* @param users !nBm}E7d
* The users to set. ikG9l&n
*/ 4eL54).1O
publicvoid setUsers(List users){ ?V:]u3
this.users = users; `+Z#*lj|@
} bK$D lBZ
`yXx[deY
/** dQ`ZrWd_U
* @param userService )wzs~Fn/
* The userService to set. m3Z}eC8LK
*/ UJ)M:~O
publicvoid setUserService(UserService userService){ O8~U<'=*
this.userService = userService; JX$NEq(
} (g2r\hI
} @3TkD_B&
qs1.@l("
)/T$H|
*
r4/|.l
^'53]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, P9mxY*K)%5
"q>I?UcZ
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 gXLZ) >+A+
\{=`F`oB=
么只需要: m<,G:?RM
java代码: 3et2\wOX1x
h)l&K%4;
qb&NS4#
<?xml version="1.0"?> eTRx 6Fri(
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork -WBz]GW4r
o7a6 )2JK
1.0//EN" "http://www.opensymphony.com/xwork/xwork- +IO1ipc4cE
<Dj$0g
1.0.dtd"> +6M+hO]
-1r &s
<xwork> ji)4WG/1
2DCcGKa"
<package name="user" extends="webwork- o- QG&
]
K!D!b'|bb
interceptors"> !0csNg!
R{xyme@"^
<!-- The default interceptor stack name $aPHl
[gh[F
--> LXu"rfp
<default-interceptor-ref %v+fN?%x,d
]1|Ql*6y,
name="myDefaultWebStack"/> nL(%&z \4
+b,31
<action name="listUser" xAd>",=~
s3_e7D ^H
class="com.adt.action.user.ListUser"> PVS<QN%
<param )4L%zl7
V3A>Ag+^~
name="page.everyPage">10</param> ['Y+z2k
<result |RAQ% VXm
:CkR4J!m3
name="success">/user/user_list.jsp</result> a[74%L?
</action> 4>"cc@8&~
4lh
</package> p-'6_\F.Ke
NzeI/f3K5
</xwork> Y:"v=EhB
eFj6p<
_z(5e
?y*+^E0
6`4W,
[
4Y
`O
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 `k}l$ih`X
,8xP8T~Kmv
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。
kF+ }.x%
s{z~Axup-
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 oLqbR?
2htA7V*dD
!,6v=n[Nz
_D2bGZN
Y7:Y{7E7
我写的一个用于分页的类,用了泛型了,hoho 4I#eC#"
mj(&`HRs4
java代码: Mi/ &$"=
]Ic?:lKN
V^`?8P8d
package com.intokr.util; (+gL#/u
|:(23O
import java.util.List; :B*vkwT
^QXw[th!d
/** zOiY0`=
* 用于分页的类<br> /\-2l+y>J
* 可以用于传递查询的结果也可以用于传送查询的参数<br> pe!dm}!h[
* o1#:j?sN
* @version 0.01 2i7i\?<.
* @author cheng s?@)a,C%k
*/ <nb3~z1
public class Paginator<E> { $p0 /6c
privateint count = 0; // 总记录数 DD@)z0W
privateint p = 1; // 页编号 O+E1M=R6h
privateint num = 20; // 每页的记录数 aucZJjH
privateList<E> results = null; // 结果 S[L#M;n
0tW<LR-}E
/** ?}=-eJ(7e
* 结果总数 U50s!Zt45
*/ $/, BJ/9
publicint getCount(){ Y[iDX#
return count; )H;pGM:
} @QVqpE<|
oTF^<I-C
publicvoid setCount(int count){ @3-,=x
this.count = count; a)_rka1(
} uEScAeQXsI
'nlRY5@2
/** lJ:M^.Em0
* 本结果所在的页码,从1开始 d`9W
* pwFU2}I
* @return Returns the pageNo. FpdDIa
*/ ]3O
4\o
publicint getP(){ Wa[x`:cT?u
return p; VDByj "%
} f=:3! k,S
wovmy{K
/** B]^>GH
* if(p<=0) p=1 T|o`a+?
* ?o~:'Z
* @param p 4#^'lKIx
*/ YH)Opk
publicvoid setP(int p){ $5TepH0D
if(p <= 0) $=PWT-GIR
p = 1; Qy=HrL]x
this.p = p; \Y!T>nWn)I
} lX98"}
Y{k>*: Ax_
/** HY jMNj0
* 每页记录数量 b&lN%+%}
*/ f{y]
publicint getNum(){ /OQK/
t63
return num; 0$eyT-:d
} ~9JW#HHzn
|'V DI]p&
/** 5l41Q
* if(num<1) num=1 ~lzdbX
*/ lQV|U;~D
publicvoid setNum(int num){ _ yfdj[Ot`
if(num < 1) X5uS>V%/
num = 1; AVXX\n\_
this.num = num; `y\*m]:
} ds*m6#1b
O^.%C`*
/** Xh.+pJl,*
* 获得总页数 $uEJn&n7}
*/ Xw7{R
publicint getPageNum(){ PUbaS{J7
return(count - 1) / num + 1; ''#p47$8<d
} rQ9*J
)!'n&UxPo$
/** )\{'fF
* 获得本页的开始编号,为 (p-1)*num+1 ss?]
*/ m"lE&AM64p
publicint getStart(){ UF@IBb}0
return(p - 1) * num + 1; #*!+b
} (Ij0AeJ#
![^EsgEB*
/** z 0~j
* @return Returns the results. x}tKewdOSe
*/ #|qm!aGs
publicList<E> getResults(){ z^4KU\/JK
return results; ET U-]R 3
} z>4D~HX
i]it5
public void setResults(List<E> results){ <=q*N;=T,
this.results = results; puFXPw.3
} +$>N]1
G1}~.%J
public String toString(){ x!'7yx
StringBuilder buff = new StringBuilder - #3{{
B{s]juPG
(); f#@S*^%V$
buff.append("{"); ;aq `N}d
buff.append("count:").append(count); vG Y!4@[
buff.append(",p:").append(p); Y4QLs^IdB
buff.append(",nump:").append(num); >@^<S_KVh
buff.append(",results:").append RnHQq'J|\
hlX>K
(results); 82lr4
buff.append("}"); aK]7vp+
return buff.toString(); E@:Q 'g%
} KwS`3 6:
zQ ,f5x
} 2=>*O
e#tIk;9Xz
egfi;8]E