Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 .Hk.'>YR
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 $/ $Hi U`.
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 F%.UpV,
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 #hk5z;J5
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分页支持类: \#IKirf?
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java代码: -wf>N:
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package com.javaeye.common.util; l%p,m[
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import java.util.List; G:@1.H`
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publicclass PaginationSupport { i|xz
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publicfinalstaticint PAGESIZE = 30; QjD=JC+
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privateint pageSize = PAGESIZE; ,`YIcrya:
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privateList items; Ypxp4B
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privateint totalCount; s%8,'3&
8'NT_NPNb
privateint[] indexes = newint[0];
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privateint startIndex = 0; [)kuu
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public PaginationSupport(List items, int cmAdQ)(Kzd
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totalCount){ .$
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setPageSize(PAGESIZE); M?o_J4
setTotalCount(totalCount); `~=NBN=tiL
setItems(items); EXwU{Hl
setStartIndex(0); ;),,Hk
} E}THG=6
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public PaginationSupport(List items, int hm
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totalCount, int startIndex){ Rf2mBjJ(z
setPageSize(PAGESIZE); Xbrc_V\_
setTotalCount(totalCount); WJ LqH<
setItems(items); }%<_>b\
setStartIndex(startIndex); 9XhH*tBn7(
} M%RH4%NZ0
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public PaginationSupport(List items, int _Vf>>tuW
#?,"/Btq
totalCount, int pageSize, int startIndex){ 8EX?/33$
setPageSize(pageSize); l2YA/9.
setTotalCount(totalCount); ,?HM5c{'[Y
setItems(items); ) jt?X}
setStartIndex(startIndex); 0c8_&
} TP~1-(M)}
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publicList getItems(){ K-K>'T9F}
return items; fVVD}GM=
} P,xJVo\
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publicvoid setItems(List items){ M*C1QQf\N
this.items = items; MmePhHf
} a.RYRq4o
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publicint getPageSize(){ dV16'
return pageSize; .p?SPR
} qQ6@43TC
cSNeWJKA6
publicvoid setPageSize(int pageSize){ 4i5b.bU$
this.pageSize = pageSize; |sl^4'Ghc
} 3+vVdvu%
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publicint getTotalCount(){ bI_MF/r''
return totalCount; @; I9e
} #!%zf{(C+
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publicvoid setTotalCount(int totalCount){ ^dsj1#3z
if(totalCount > 0){ ]ms+Va_/
this.totalCount = totalCount; 1L!jI2~x}
int count = totalCount / `e?~c'a@
O:
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pageSize;
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if(totalCount % pageSize > 0) ~*UY[!+4^=
count++; 7,8TMd1`M
indexes = newint[count]; 8?x:PkK
for(int i = 0; i < count; i++){ pYu6[
indexes = pageSize * /L5:/Z
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->
i; 3-)}.8F
} 3 `mtc@*
}else{ WwWCNN~}
this.totalCount = 0; D*?LcxX
} g+c%J#F=
} {MTtj4$
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publicint[] getIndexes(){ eH[i<Z
return indexes; x5Fo?E
} zA:q/i
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publicvoid setIndexes(int[] indexes){ A wk1d
this.indexes = indexes; ;sq xFF@
} zK{}
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publicint getStartIndex(){ 9_e_Ne`i`?
return startIndex; 3(vm'r&5n>
} ='_3qn.
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@
publicvoid setStartIndex(int startIndex){ 79-50}A
if(totalCount <= 0) x;-D}#
this.startIndex = 0; }UQ,B
elseif(startIndex >= totalCount) K[
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this.startIndex = indexes 0vBQzM Q
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[indexes.length - 1]; Zk>m!F>,p
elseif(startIndex < 0) a/3'!} &e
this.startIndex = 0; t~nW&]E
else{ %+;l|Z{Uf
this.startIndex = indexes 5,V*aP
"r3h+(5
[startIndex / pageSize]; 3bjCa\ "
}
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} fX6pW%Q'6
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publicint getNextIndex(){ H{Lt,#
int nextIndex = getStartIndex() + f5l\3oL
}[MkJ21!
pageSize; csxn"Dz\
if(nextIndex >= totalCount) .tyV=B:h
return getStartIndex(); </?ef&
else 8G|?R#&
return nextIndex; m({q<&]Qp
} q;IuV&B
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publicint getPreviousIndex(){ D%c^j9' 1
int previousIndex = getStartIndex() - UQ7La 7"
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pageSize; ?~#[cx
if(previousIndex < 0) Z7[S698
return0; J^%E$s
else ^Jdg%U?
return previousIndex; #o9CC)q5G
} ITi#p%
!|]k2=+I
} ,Mi'NO
cz>)6#&O
D`X<b4e8/
#F2DEo^0
抽象业务类 burSb:JF
java代码: :`"-Jf
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AN[pjC<
/** pS7y3(_
* Created on 2005-7-12 61OlnmvE
*/ @\xEK5 SG
package com.javaeye.common.business; }1+2&Ps50
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import java.io.Serializable; _5O~]}
import java.util.List; %W| Sl
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import org.hibernate.Criteria; C=U4z|Ym
import org.hibernate.HibernateException; 9f5~hBlo
import org.hibernate.Session; 1&7?f
import org.hibernate.criterion.DetachedCriteria; O:RN4/17
import org.hibernate.criterion.Projections; (b&Z\?"
import W[]|Uu/%
[fb9;,x`
org.springframework.orm.hibernate3.HibernateCallback; O#C0~U]dDW
import :eB+t`M
KV9~L`=]i
org.springframework.orm.hibernate3.support.HibernateDaoS yfR0vp<&
KM"?l<x0Y
upport; 7!m<d,]N
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import com.javaeye.common.util.PaginationSupport; 5nceOG8
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public abstract class AbstractManager extends >c5
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HibernateDaoSupport { xS+xUi
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privateboolean cacheQueries = false; xy$aFPH!-
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privateString queryCacheRegion; 5INw#1~
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publicvoid setCacheQueries(boolean ;'Z"CbS+
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cacheQueries){ T('rM:)/
this.cacheQueries = cacheQueries; lb=fS%
} ,pf\g[tz
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publicvoid setQueryCacheRegion(String 85] 'I%gT
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queryCacheRegion){ lU&2K$`
this.queryCacheRegion = 9(vp`Z8B4
"SWL@}8vx
queryCacheRegion; ,nP nH1vb
} n-qle5s j
3!QXzT$E
publicvoid save(finalObject entity){ Xa$%`
getHibernateTemplate().save(entity); *H=h7ESq
} !O'p{dj][
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publicvoid persist(finalObject entity){ yOb']
getHibernateTemplate().save(entity); mRGr+m
} nKtRJ,>
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publicvoid update(finalObject entity){ =T?Xph{
getHibernateTemplate().update(entity); i??+5o@uTF
} HxLuJ
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publicvoid delete(finalObject entity){ IEJ)Q$GI#
getHibernateTemplate().delete(entity); Txpj#JD
} H/8u?OC
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publicObject load(finalClass entity, 6!*zgA5M'
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finalSerializable id){ Iq6EoDoq
return getHibernateTemplate().load bS55/M w
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(entity, id); a_b+RMy
} By}ZHK94I
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publicObject get(finalClass entity, %P#|
}
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finalSerializable id){ {c drMP@""
return getHibernateTemplate().get K!E\v4
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(entity, id); $~
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} wXBd"]G)C
CR#-!_=4
publicList findAll(finalClass entity){ I{%(G(
return getHibernateTemplate().find("from ~HtD]|7
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" + entity.getName()); j{=}?+M
} 7.n\a@I/
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publicList findByNamedQuery(finalString g ssEdJ
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namedQuery){ 4wa3$Pk
return getHibernateTemplate .6bo
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().findByNamedQuery(namedQuery); v"Ryg]^_
} \]\GDpu[
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publicList findByNamedQuery(finalString query, X;vUz
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finalObject parameter){ XZ(<Mo\v
return getHibernateTemplate jr-9KxE
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().findByNamedQuery(query, parameter); SVV-zz]3M
} mfDt_Iq
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publicList findByNamedQuery(finalString query, RgM=g8}M
@|'9nPern
finalObject[] parameters){ kKC]
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return getHibernateTemplate Sb)}
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().findByNamedQuery(query, parameters); V;~\+@
} Lo}/k}3Sx
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publicList find(finalString query){ 6D{70onY+
return getHibernateTemplate().find *$1F|G
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(query); yRQNmR;Uy
} #}tdA(
-
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publicList find(finalString query, finalObject #AO}JP
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parameter){ ^R7X!tOq4
return getHibernateTemplate().find YXdo&'Q<qX
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(query, parameter); :."+&gb
} gh^w
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public PaginationSupport findPageByCriteria %?S[{ 4A&
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(final DetachedCriteria detachedCriteria){ sdgI ,
return findPageByCriteria Az>r}*FGr
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ,.<c|5R
} BcQw-<veu
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public PaginationSupport findPageByCriteria RYl\Q,#
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(final DetachedCriteria detachedCriteria, finalint aH,NS
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startIndex){ @;S)j!m`
return findPageByCriteria q+w] Xs;
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(detachedCriteria, PaginationSupport.PAGESIZE, ZHj7^y@P
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startIndex); 7p{uRSE4._
} ]2[\E~^KU
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public PaginationSupport findPageByCriteria CT<z1)#@^
"
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(final DetachedCriteria detachedCriteria, finalint 'P%&*%
wx2 z 9Q
pageSize, QG@Z%P~,E
finalint startIndex){ lJS3*x#H
return(PaginationSupport) QlH[_Pi
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getHibernateTemplate().execute(new HibernateCallback(){ FEV Ya#S
publicObject doInHibernate G('UF1F
v|3mbApv
(Session session)throws HibernateException { C9>^!?>
Criteria criteria = -Gm}i8;
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detachedCriteria.getExecutableCriteria(session); %PK(Z*>
int totalCount = Gxt6]+r
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((Integer) criteria.setProjection(Projections.rowCount N)KN!!
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()).uniqueResult()).intValue(); ;YBk.}
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criteria.setProjection 9h6siK(F
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(null); C2DAsSw
List items = GAh\6ul
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criteria.setFirstResult(startIndex).setMaxResults $5Rx>$~+d
v,iq,p)&
(pageSize).list(); fA ),^
PaginationSupport ps = /\E3p6\*
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new PaginationSupport(items, totalCount, pageSize, ~D/1U)kt
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startIndex); 1Z_ H%(
return ps;
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} w3ZOCWJS
}, true); 5<7sVd.
} @ xTVX'$
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public List findAllByCriteria(final Nfmr5MU_
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DetachedCriteria detachedCriteria){ /In=u6D O
return(List) getHibernateTemplate e
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().execute(new HibernateCallback(){ 4-C'2?
publicObject doInHibernate G
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(Session session)throws HibernateException { RiIafiaD
Criteria criteria = >#Bu [nD%
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detachedCriteria.getExecutableCriteria(session); t
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return criteria.list(); +zl[C
} xb&,9Lxd|
}, true); 5BM6Pnle
} mdcsL~R
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public int getCountByCriteria(final )6px5Vwz
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DetachedCriteria detachedCriteria){ ^ Qxv5HS2
Integer count = (Integer) 5wv7]F<
! 'Hd:oD<
getHibernateTemplate().execute(new HibernateCallback(){ =RofC9,
publicObject doInHibernate mRC
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(Session session)throws HibernateException { hXD/
Criteria criteria = 6E_YUk?KW
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detachedCriteria.getExecutableCriteria(session); zV"'-iP
return <."
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criteria.setProjection(Projections.rowCount nrbP3sf*
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()).uniqueResult(); Z!l]v.S
} Nema>T]
}, true); G"Hj$
return count.intValue(); :_o^oi7G
} oZi{v]4
} U/h@Q\~U
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用户在web层构造查询条件detachedCriteria,和可选的 @Z<Z//^k
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 vr_Z0]4`C9
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PaginationSupport的实例ps。 6<f(Zv? I
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ps.getItems()得到已分页好的结果集 U+!&~C^y
ps.getIndexes()得到分页索引的数组 WDt 6{5T
ps.getTotalCount()得到总结果数 *0<)PJ T
ps.getStartIndex()当前分页索引 F]s:`4
ps.getNextIndex()下一页索引 x1}Ono3"T
ps.getPreviousIndex()上一页索引 Uyd' uC
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 r^ABu_u(`I
0:B%,nUM
,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 Sar1NkD#
.=9d3uWJ/
一下代码重构了。 4`")aM
S,vdd7Y
我把原本我的做法也提供出来供大家讨论吧: rCb#E}
(D{J|
首先,为了实现分页查询,我封装了一个Page类: z:u)@>6D1
java代码: bc>&Qj2Z7c
R 'fEw3^
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/*Created on 2005-4-14*/ Bi>]s%zp
package org.flyware.util.page; s5)y%,E
A,3qjd,$ c
/** i>dFpJ
* @author Joa jWdZ]0m
* g2A#BMe'.$
*/ >B;KpO"+m
publicclass Page { ]kF1~kXBe
+ f:!9)C
/** imply if the page has previous page */ zU_dk'&,
privateboolean hasPrePage; %OP|%^2
Fqh./@o
/** imply if the page has next page */ (B!DBnq
privateboolean hasNextPage; <-,y0Y'
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/** the number of every page */ z:1t
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privateint everyPage; zV(aw~CbZ
F_4Et
/** the total page number */ E0+~c1P-
privateint totalPage; U\M9sTqo
ES8(:5
/** the number of current page */ DhD##5a
privateint currentPage; <5}j(jxz}
: t/0
/** the begin index of the records by the current aX
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xC}' "``s
query */ @#;*e] 1a
privateint beginIndex; \C4wWh-A
<2~DI0pp(
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/** The default constructor */ ,LDL%<7t
public Page(){ @Bn4ZFB@
m;L3c(r.
} 7xYz9r)w`
)g}G{9M^
/** construct the page by everyPage c c/nzB
* @param everyPage [70 5[
* */ 1/K1e$r
public Page(int everyPage){ 2<:dA >1
this.everyPage = everyPage; fzvyR2 I
} OXn-!J90P
qVH.I6)
/** The whole constructor */ +wQ}ZP&
public Page(boolean hasPrePage, boolean hasNextPage, M0OIcMTv
^YB2E*
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int everyPage, int totalPage, +;M 5Sp
int currentPage, int beginIndex){ 0)ZLdF_6
this.hasPrePage = hasPrePage; Qqk(,1u
this.hasNextPage = hasNextPage; iSg0X8J)
this.everyPage = everyPage; # s7e/GdKb
this.totalPage = totalPage; xvomn`X1
this.currentPage = currentPage; p1("
this.beginIndex = beginIndex; {-f%g-@L6|
} eKZS_Q d
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/** ]>%2,+5
* @return 3i'01z
* Returns the beginIndex. VL'wrgk
*/ V`HnFAW
publicint getBeginIndex(){ z4$9,p
`
return beginIndex; :"H?phk
} g,W34*7=Q
L
4Z+8*
/** N
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* @param beginIndex PN:`SWP
* The beginIndex to set. .rnT'""i<5
*/ rBy0hGx
publicvoid setBeginIndex(int beginIndex){ 62y:i
this.beginIndex = beginIndex; R0LWuE%eD
} lNl.lI\t)y
%r*,m3d
/** \fuz`fK:
* @return ;jN1n
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* Returns the currentPage.
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*/ LsaX
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publicint getCurrentPage(){ :8==Bu
return currentPage; >Gk<a
} po,Ue>n/
%[M0TE=J
/**
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* @param currentPage H)EL0
Kv/
* The currentPage to set. GIn%yB'
*/ {2q0Ko<
publicvoid setCurrentPage(int currentPage){ 8eYEi
this.currentPage = currentPage; } # L_R
} r/"^{0;F{W
pU'>!<zGr
/** Gf:dN_e6.
* @return pl)?4[`LUc
* Returns the everyPage. AO|1m$xf
*/ ^u1Nbo
publicint getEveryPage(){ 8#- Nx]VM
return everyPage; uXLZ!LJo
} %e3E}m>
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/** V\opC6*L_e
* @param everyPage DS>&|zF5l
* The everyPage to set. vqO#Z
*/ dNF_T?E\
publicvoid setEveryPage(int everyPage){ `'k2gq&
this.everyPage = everyPage;
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} * fj`+J
uOy/c 8`
/** v ?}0h5
* @return $xq04ejJ
* Returns the hasNextPage. 5??}9
*/ ysl#Rwt/2
publicboolean getHasNextPage(){ s S#/JLDx]
return hasNextPage; 3}&3{kt
} DHx&%]r;D
$!y^t$u$@
/** JYA>Q&
* @param hasNextPage hvNK"^\p
* The hasNextPage to set. yNn=r;FZQ
*/ EltCtfm`
publicvoid setHasNextPage(boolean hasNextPage){ ,d&3IhYhD
this.hasNextPage = hasNextPage; S<*IoZ?T
} ,Z _@]D@
3S2Alx!6
/** #7}M\\$M
* @return y'I
m/{9U
* Returns the hasPrePage. %#eQN
~
*/ A'b$X1h
publicboolean getHasPrePage(){ 8"g+
k`PRy
return hasPrePage; MSeg7/ MF
} =T&<z_L
e84%Y8,0
/** 0GeL">v,:=
* @param hasPrePage \AA9
m'BZ
* The hasPrePage to set. Ip=QtNW3\
*/ g,M-[o=Fk
publicvoid setHasPrePage(boolean hasPrePage){ d;wq@e
this.hasPrePage = hasPrePage; js"5{w&
} )oz2V9X{
%dq%+yw{%m
/** F kf4R5Y?
* @return Returns the totalPage. d|7LCW+HW
* &FT`z"^
*/ VP^Yf_
publicint getTotalPage(){ Zf<T`'_d
return totalPage; = >tkc/aa
} b7I0R;Zj
J5HK1
/** |9IOZ>H9
* @param totalPage l&e$:=;8
* The totalPage to set. 3oH/34jj
*/ 9&.md,U '
publicvoid setTotalPage(int totalPage){ C4.GtY8,d
this.totalPage = totalPage; K%mR=u#%&
} Y,Rr[i"j
G)t-W%D&
} q/ 54=8*h0
nXoDI1<[
K<`Z@f3'w
l"nS+z
3o?eUwI}
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 'VCuMCV
.r6x9t
个PageUtil,负责对Page对象进行构造: 1Q? RD%lkf
java代码: PlLt^q.z[
X#JUorGp
oQu>Qr{Zp
/*Created on 2005-4-14*/ |Rkw/5
package org.flyware.util.page; K/f-9hE F
5|K[WvG@Co
import org.apache.commons.logging.Log; "G.X=,
V
import org.apache.commons.logging.LogFactory; r~f;g9I
n5.sx|bI?
/** Hv^Bw{"/R
* @author Joa 2zh-ms
* tp7$t#
*/ 0:u:#))1
publicclass PageUtil { Bl8|`R^g
&?H$-r1/?V
privatestaticfinal Log logger = LogFactory.getLog 7Vh
aEIz,^3
(PageUtil.class); JJ_Z{
~S;-sxoO0l
/** Q>Z~={"
* Use the origin page to create a new page gH'hA'
* @param page jI*@&3
* @param totalRecords wS#Uw_[
* @return 6fo"k+S
*/ w(S~}'Sg*P
publicstatic Page createPage(Page page, int iCg%$h
e"eIQI|N
totalRecords){ :}Yk0*
return createPage(page.getEveryPage(), Hv,ll1@h
U), HrI>;
page.getCurrentPage(), totalRecords);
nYZ6'Iwi'
} Y)5O %@Rl
la-:"gKC
/** *!&?Xy%\"j
* the basic page utils not including exception ,pGA|ob
4}/gV)
handler f)z(9JJL
* @param everyPage E wFq1~
* @param currentPage `P !idg*
* @param totalRecords pInEB6L.P
* @return page 3I~.'>Pd
*/ 9S}rTZkEq
publicstatic Page createPage(int everyPage, int `H$XO{w
#\m.3!Hcr
currentPage, int totalRecords){ rnhLv$
everyPage = getEveryPage(everyPage); 0LL0\ly]
currentPage = getCurrentPage(currentPage); dEKu5GI
int beginIndex = getBeginIndex(everyPage, ?yq=c
.9B@w+=6
currentPage); 0,DrVGa
int totalPage = getTotalPage(everyPage, ^IuhHP
a?r$E.W'&
totalRecords); r2.w4RMFua
boolean hasNextPage = hasNextPage(currentPage, _&V,yp!|
u$[8Zmgzz
totalPage); PLs`Ci|`
boolean hasPrePage = hasPrePage(currentPage); tR'RB@kJ
M`'DD-Q
returnnew Page(hasPrePage, hasNextPage, _1G/qHf^S
everyPage, totalPage, P<vU!`x%q
currentPage, @- |G_BZ
t7x<=rW7u
beginIndex); [[AO6.Z
} B47 I?~{
$RY GAh
privatestaticint getEveryPage(int everyPage){ L f"!:]
return everyPage == 0 ? 10 : everyPage; Fovah4q%V
} bs)wxU`Q*
+O 7(
>a
privatestaticint getCurrentPage(int currentPage){ ;#v3C;
return currentPage == 0 ? 1 : currentPage; >\?
z,Nin
} ZJ)Z
zqNzWX
privatestaticint getBeginIndex(int everyPage, int rY^uOrR>j*
w$f_z*/
currentPage){ HSG Ln906
return(currentPage - 1) * everyPage; H6 x
} #n|5ng|CJ
=oL:|$Pj
privatestaticint getTotalPage(int everyPage, int PL$XXj>|:
8HBwcXYoHh
totalRecords){ IP#vfM
int totalPage = 0; TA*}p=?6?!
n)q8y0if
if(totalRecords % everyPage == 0) 0:[A4S`X
totalPage = totalRecords / everyPage; L
QV@]z&
else #1'q'f:7&
totalPage = totalRecords / everyPage + 1 ; (b#M4ho*f
}'x)e
return totalPage; yVK
;
"
} c{y'&3\
|f$+|9Q?
privatestaticboolean hasPrePage(int currentPage){ a}NB6E)-
return currentPage == 1 ? false : true; !vu-`u~86
} i:jXh9+
Oz-/0;1n
privatestaticboolean hasNextPage(int currentPage, g*oX`K.
iEtR<R>=
int totalPage){ ^z)De+,!4
return currentPage == totalPage || totalPage == \HzmhQb+m
GZrN,M
0 ? false : true; 7:vl -ZW
} X(BxC<!D.
61kSCu
BI)C\D3[
} C;JW\J~W
#bt f|\D
9;7"S.7AV
@B>D>B
7_s+7x =
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。
B(s^(__]
8TB|Y
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 m"Mj3Z:
r4iNX+h?V
做法如下: V||b%Cb1g
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 zx\-He
de W1>yh^_
的信息,和一个结果集List: ]FVJQS2h
java代码: )YEAk@h@
W>w(|3\
EL3X8H
/*Created on 2005-6-13*/ `(?c4oq,c>
package com.adt.bo; l]zQSXip
L1!~T+%uQ
import java.util.List; Ir>4- @
s;oe Qa}TB
import org.flyware.util.page.Page; hv#$Zo<
fWEQ vQ
/** M("sekL
* @author Joa w#A\(z%;x
*/ i,;eW&
publicclass Result { z-gMk@l
d6tv4Cf
private Page page; sNpA!!\PM
2=K|kp5
private List content; sHBTB6)lx
ghB&wOm/
/** 6ZHeAb]"
* The default constructor 3^wHL:u
*/ !6X6_ +}M
public Result(){ P/ 6$TgQ
super(); v?]a tb/h`
} F68eI%Y
[sH3REE1h
/** z~`X4Segw
* The constructor using fields M-h+'G
* n!Y_SPg
* @param page J7",fb
* @param content Yu" Q
*/ oCkG
public Result(Page page, List content){ ].J;8}
this.page = page; fTR6]i;
this.content = content; 6:%lxG
} )ddJ\:
R$l-
7YSt
/** bFN/{^SB
* @return Returns the content. n7;jME/!
*/ !Q~>)$Cf^
publicList getContent(){ D['J4B
return content; @R`6jS_gK
} D
ON.)F
E@k'uyIu
/** XTX/vbge3m
* @return Returns the page. y{3+Un
*/ R3og]=uFzm
public Page getPage(){ Iv3O8GU
return page; ~xY"P)(x;
} S[$9_J f
!\{2s!l~
/** .F@Lx45
* @param content TEo
* The content to set. h9m|f|cH
*/ 3t+{~{Dj
public void setContent(List content){ 6|q"lS*$S
this.content = content; | WJ]7C
} fgL"\d}
YC 4c-M
/** WG A&Lr
* @param page 7Dssr [
* The page to set. Ww8U{f
*/ "4WnDd5"
publicvoid setPage(Page page){ \; '#8
this.page = page; %fS1gSfh
} v7@"9Uw}
} ku*k+4rz
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k0I$x:c
j}Svb1A
-a_qZ7
2. 编写业务逻辑接口,并实现它(UserManager, 3C!|!N1Hn
'MYKAnZ-i
UserManagerImpl) . mO8~Z
java代码: Y9f7~w^s
r0k:RJP
x1wD`r
/*Created on 2005-7-15*/ H(n
fHp.3
package com.adt.service; S"Vr+x?
UGM:'xa<T
import net.sf.hibernate.HibernateException; 9=iMP~?xF
d!<>Fh^6,
import org.flyware.util.page.Page; J|U~W
kW
oq|o"n)~
import com.adt.bo.Result; \2El>>
r%=a :GdAg
/** k~<Ozx^AyY
* @author Joa e^\(bp+83
*/ ]6v7iuvI
publicinterface UserManager { xv$fw>
@(=?x:j
public Result listUser(Page page)throws qOpwl*?x+
t OnOzD
HibernateException; )cQ KR4x0^
!X"nN9k
} aDz%
%%:r
+ah4 K(+3
3C=QWw?
dMjQV&
3_;=y\F
java代码: ?\4kV*/Cqz
$Nvox<d0
)2W7>PY
/*Created on 2005-7-15*/ -u~:Gd*l0
package com.adt.service.impl; V3*@n*"N;
|uFb(kL[U
import java.util.List; g1F9IB42@<
UjunIKX+
import net.sf.hibernate.HibernateException; 1n2Pr'|s
:SN? t
import org.flyware.util.page.Page; ixM#|Yq
import org.flyware.util.page.PageUtil; mBrZ{hqS
v%`k*n':
import com.adt.bo.Result; X eis_
import com.adt.dao.UserDAO; JT6Be8
import com.adt.exception.ObjectNotFoundException; B[w.8e5
import com.adt.service.UserManager; ${. :(z
0.!vp?
/** d\A7}_r*x
* @author Joa Xsb.xxK.
*/ H_Hr=_8}-
publicclass UserManagerImpl implements UserManager { c2GTN "
3M[d6@a
private UserDAO userDAO; _ !"[Zr
buKkm$@w
/** `tH F}
* @param userDAO The userDAO to set. I)%bOK]
*/ J~@W":v
publicvoid setUserDAO(UserDAO userDAO){ ZW;Re5?DJ
this.userDAO = userDAO;
S[8nGH#m
} { }Afah
ed/
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/* (non-Javadoc) =y?Aeqq\fl
* @see com.adt.service.UserManager#listUser :[_k .1-+
ZLP0SCkuR
(org.flyware.util.page.Page) i-95>ff
*/ 8*VQw?{Uee
public Result listUser(Page page)throws |t$%kpp
0"sZP\<p
HibernateException, ObjectNotFoundException { WT 5 2
int totalRecords = userDAO.getUserCount(); h}m9L!+n8
if(totalRecords == 0) Xe
^NVF
throw new ObjectNotFoundException A}uWy^w
|D;I>O^"R
("userNotExist"); |F=.NY
page = PageUtil.createPage(page, totalRecords); dt=M#+g
List users = userDAO.getUserByPage(page); lH,/N4r*&
returnnew Result(page, users); ,k:>Z&:
} ^m.%FIwR
2R3)/bz-SV
} -ebyW#
j3?@p5E(
\$,;@H5I^
e/)Vx'd`+
`- 9p)@'8k
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 sw(|EZ7F
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+
k
询,接下来编写UserDAO的代码: "GxQ9=Z
3. UserDAO 和 UserDAOImpl: ){tTB
java代码: gHH[QLD=I
IV`+B<3
.g_Kab3?L
/*Created on 2005-7-15*/ 9PR?'X;4
package com.adt.dao; N71%l
[GW;RjPE
import java.util.List; uH} }z !
y 5Kr<cF^
import org.flyware.util.page.Page; vF{{$)c
K>2 Bz&)
import net.sf.hibernate.HibernateException; 9$R}GK
UtB~joaR
/** Hq <!&
* @author Joa Ez^wK~
*/ al]-*=v7}
publicinterface UserDAO extends BaseDAO { QIcc@PGT9a
0*/[z~Z-1
publicList getUserByName(String name)throws [Al}GM
eyByAT~W,
HibernateException; l.SoiFDd
jxgs!B>
publicint getUserCount()throws HibernateException; _$gP-J
_GL:4
publicList getUserByPage(Page page)throws Gl>*e|}
!ac,qj7spa
HibernateException; ]RI+:f
FlLk.+!t
} T5TAkEVl
x?G"58
";w"dfC^
(5=B^9{R
{=T9_c
java代码: 843O}v'
P?`a{sl.
SGLU7*sfd
/*Created on 2005-7-15*/ 3c[TPD_:
package com.adt.dao.impl; v6'k`HnK
s>e)\9c
import java.util.List; u_%L~1+'
Nb/Z +
import org.flyware.util.page.Page; /baSAoh/e
/G!M\teeF
import net.sf.hibernate.HibernateException; &^K,"a{
import net.sf.hibernate.Query; Au{J/G<W@
9at_F'>R
import com.adt.dao.UserDAO; I73=PfS:m
zXv2plw(
/** SH1)@K-
* @author Joa Gxh1wqLR
*/ CdNb&Nyz
public class UserDAOImpl extends BaseDAOHibernateImpl e6I7N?j
!TPKD
implements UserDAO { ee
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7NQEn Al
/* (non-Javadoc) kuo!}QFL
* @see com.adt.dao.UserDAO#getUserByName HV8=b"D"
/zIUYY
(java.lang.String) ->a|
*/ Ox&]{
publicList getUserByName(String name)throws 8QFg6#"O
C "g bol^
HibernateException { )cBO_
String querySentence = "FROM user in class =]W[{@P
!4(QeV-=
com.adt.po.User WHERE user.name=:name"; }<=_&n
Query query = getSession().createQuery "<yJ<lS&>
klx28/]
(querySentence); P?j ;&@$^e
query.setParameter("name", name); YaAOP'p
return query.list();
L }pj+xB
} A\)~y{9bQ
fsUZG6
/* (non-Javadoc) b_a6|
* @see com.adt.dao.UserDAO#getUserCount() L_R(K89w
*/ Eanwk` Rx
publicint getUserCount()throws HibernateException { 9}aEV 0 V|
int count = 0; @ x5LrQ_`r
String querySentence = "SELECT count(*) FROM g0:{{w
#,Cz+k*4
user in class com.adt.po.User"; 5b;~&N4~
Query query = getSession().createQuery sff4N>XAl<
Y@2yV(m)o
(querySentence); EfGy^`,'G
count = ((Integer)query.iterate().next z^\-x9vL
q:u,)6
()).intValue(); tYMPqP,1.
return count; 1}3tpO;
} `{9bf)vP6
yVgHu#?PM
/* (non-Javadoc) q0VR&b`?>D
* @see com.adt.dao.UserDAO#getUserByPage QfRo`l/V9
63Z^ k(
(org.flyware.util.page.Page) !AN;
*/ #N;McF;W
publicList getUserByPage(Page page)throws R 0YWe
Y |9
HibernateException { 8\HzFB
String querySentence = "FROM user in class *g[MGyF"
%{&,5|8
com.adt.po.User"; 59BB-R,V
Query query = getSession().createQuery 9E}JtLgT
7R$O~R3p
(querySentence); jR>`Xz
query.setFirstResult(page.getBeginIndex()) -.l.@
.setMaxResults(page.getEveryPage()); Q2<v: *L
return query.list(); %#C9E kr
} [I`:%y
#|=Q5"wU
} ~,.'#=V
(h'Bz6K
8yk4#CZ
YFP<^y=
JJy.)-R
至此,一个完整的分页程序完成。前台的只需要调用 H
h35cj
bD.KD)5
userManager.listUser(page)即可得到一个Page对象和结果集对象 zZ;V9KM>v
2WC$r8E
的综合体,而传入的参数page对象则可以由前台传入,如果用 7QRkXs
Sg*+!
webwork,甚至可以直接在配置文件中指定。 Z?u}?-b1\H
p4D.nB8
下面给出一个webwork调用示例: Z{x)v5yh2V
java代码: ^0 &jy:{
R]3j6\
J vq)%t8q>
/*Created on 2005-6-17*/ D7=Irz!O\7
package com.adt.action.user; !6,rN_a@Y
v[V7$.%5Q
import java.util.List; v2k@yxt(
tXcZl!3x
import org.apache.commons.logging.Log; s"R5'W\U
import org.apache.commons.logging.LogFactory; [}yPy))A
import org.flyware.util.page.Page; c#TV2@
,0{x-S0jX<
import com.adt.bo.Result; ),Hr
import com.adt.service.UserService; 'I$kDM mwh
import com.opensymphony.xwork.Action; \>x1#Vr>#V
=\G`g#
/** NxnaH!wS
* @author Joa M4(57b[`
*/ (I/iD.A
publicclass ListUser implementsAction{ ]-_ ma
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privatestaticfinal Log logger = LogFactory.getLog ?TJ4L/"(k6
GL~
Wnt
(ListUser.class); NF7
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private UserService userService; 0s79rJ
r6GXmr
private Page page; xT(0-o*
X ]W)D
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privateList users; *,t/IA|
&XCP@@T
/* N3N~z1x0h
* (non-Javadoc) Ve${g`7&
* >'4$g7o,
* @see com.opensymphony.xwork.Action#execute() ,:2Z6~z{
*/ \iaZV.#f
publicString execute()throwsException{ 3iUJ!gK
Result result = userService.listUser(page); g/}d> 6
page = result.getPage(); #RbdQH !
users = result.getContent(); |}UA=? Xl
return SUCCESS; 9yaTDxB>
} &nwS7n1eb
pU'${Z~b
/** M?DZShkV_
* @return Returns the page. EV-sEl8ki
*/ _>BYUPY
public Page getPage(){ Zb2PFwcy
return page; Bex;!1
} 0U:X[2|)
JdLPIfI^
/** `JY+3d,Ui
* @return Returns the users. bI|{TKKN&P
*/ 5gV,^[E-z
publicList getUsers(){ L>mM6$l
return users; LT>_Y`5>
} [VqiF~o,
A+GRTwj
/** l0;u$
* @param page ]uF7HX7F
* The page to set. E_I-.o|
*/ S=lCzL;j"
publicvoid setPage(Page page){ h Ypj
this.page = page; rsa_)iBC
} /W`CqJk-*.
^#C+l
/** U;TS7A3
* @param users |vm-(HY!
* The users to set. jSM`bE+"
*/ OI*ltba?
publicvoid setUsers(List users){ Ly3!0P.<
this.users = users; F_g(}wE#
q
} ]n>9(Mp!M
mtkZF{3Jx
/** ms;zC/
* @param userService ]kx<aQ^
* The userService to set. 0^\H$An*k
*/ #pgD-0_
publicvoid setUserService(UserService userService){ 5z9hcQAS
this.userService = userService; p`rjWpH
} U,7
} jnbR}a=fJ
>~Gy+-
9H;Os:"\|
s8[(
r7>FH!=:
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, 9M'"q7Kh
R-dv$z0
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 AzF*4x
h.]^ o*DJ
么只需要: /e6\F7
java代码: vVmoV0kGt
vWcU+GBZI
+hRAU@RA
<?xml version="1.0"?> {d(@o!;Fi
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork vz*QzVk1
3Qfj=;
4
1.0//EN" "http://www.opensymphony.com/xwork/xwork- u)MdFz
:e`;["(,
1.0.dtd"> kb]PWOz
[ K;3Qf)
<xwork> q<yp6Q3^
S
v$%-x^t
<package name="user" extends="webwork- Oj6 -
kcVEE)zb
interceptors"> L\XnTL{
{ ,qm=Xjq
<!-- The default interceptor stack name 8TZNvN4u
PW x9CT
--> \m~?mg"#
<default-interceptor-ref <T+)~&g$
%Iw6oG
name="myDefaultWebStack"/> /\V-1 7-
F$7>q'#
<action name="listUser" d:.S]OI0
1WRQjT=o
class="com.adt.action.user.ListUser"> <spV Up
<param qR/~a
3,=97Si=
name="page.everyPage">10</param> {b6| wQ\
<result gE]6]L
GuPxN}n
5
name="success">/user/user_list.jsp</result> 8i/5L=a"`
</action> Gjfb<
DJvmwFx
</package> mN?y\GB
T^> ST
</xwork> FD:3;nUY7
AI0YK"c?
4u- mE
v1h\
6r'
Oo^kV:.)
.\XFhOsa
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 /.P9n9
!Hq$7j_
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 2o2jDQ|7
@6\Id7`Ea
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 KT$Za
R8LJC]6Bh
ovm109fTx
V>D8l @
4eH:eCZze
我写的一个用于分页的类,用了泛型了,hoho @h7)M:l
D$@5$./
java代码: pGz 5!d
czNi)4x
prtNfwJz1j
package com.intokr.util; m31l[e
O|%03q(
import java.util.List; x*>@knP<-
Qw>~]d,Z
/** c12mT(+-
* 用于分页的类<br> NxY B)`~
* 可以用于传递查询的结果也可以用于传送查询的参数<br> %8Eu{3
* @^P<(%p
* @version 0.01 S7pf
QF
* @author cheng AXnRAW
*/ CjR!dh1w_
public class Paginator<E> { eX)'C>4W
privateint count = 0; // 总记录数 u}I-#j)wap
privateint p = 1; // 页编号 O-P'Ff"}t
privateint num = 20; // 每页的记录数 Td,2.YMQ
privateList<E> results = null; // 结果 zF:
:?L~
u@&e{w~0
/** +;r1AR1)x
* 结果总数 U]/iPG&_
*/ "x1?T+j4
publicint getCount(){ Me;XG?`
return count; /q1k)4?E
} YV%y
KD
~mBY_[_s=
publicvoid setCount(int count){ g[G+s4Nv
this.count = count; n_~u!Ky_P
} ~jz!jF~I
gXJtk;
/** 2i9FzpC3
* 本结果所在的页码,从1开始
V.w
L
* jk(tw-B
* @return Returns the pageNo. ?+)>JvWDz
*/ p
:{,~
1
publicint getP(){ :m]KVcF.
return p; ql/K$#u
} )6U6~!k
q@i>)nC R
/** zv.#9^/y
* if(p<=0) p=1 DpCe_Vb%M
* F\u]X
* @param p Z.}Z2K
*/ "+XF'ZO
publicvoid setP(int p){ kz0pX-@b
if(p <= 0) #~}4< 18
p = 1; -%fc)y&$
this.p = p; +MR]h
[
} xig4H7V
q$7w?(Lk
/** V36u%zdX5n
* 每页记录数量 [_T6
*/ Ly46S
publicint getNum(){ >O]u4G!
return num; !w1acmo<_
} >//yvkZ9,
M{z&h>
/** &3Y "Zd!
* if(num<1) num=1 _xsHU`(J#
*/ OYyF*F&S[
publicvoid setNum(int num){ C5,\DdCX,
if(num < 1) ,NAwSmocVP
num = 1; U|
T}0
this.num = num; Sq]VtQ(
} wY]ejK$0R
`\beQ(g
/** F4NMq&_
* 获得总页数 fJ GwT
*/ &>n:7
publicint getPageNum(){ ffW-R)U|3
return(count - 1) / num + 1; l&|Tb8_'
} bg\9Lbjr
G#L6;
/** L,yq'>*5s
* 获得本页的开始编号,为 (p-1)*num+1 QsX`IYk
*/ g'+2bQ
publicint getStart(){ :]JMsa6
return(p - 1) * num + 1; )Vz=:.D
} 3qQ}U}-; |
_RNP_$a
/** Py`7)S
* @return Returns the results. |Ed?s
*/ w1EB>!<;tj
publicList<E> getResults(){ Zd|u>tn
return results; v4]#Nc$~T
} e/uLBZ
Alv"D
public void setResults(List<E> results){ 8UzF*gS
this.results = results; Xz?7x0)Z
} !q~f;&rg
1! j^
public String toString(){ hzk4SOT(
StringBuilder buff = new StringBuilder xyP0haE
},=ORIB B:
(); N(e>]ui
buff.append("{"); a51}~V1
buff.append("count:").append(count); )j QrD`
buff.append(",p:").append(p); ol1J1Zg
buff.append(",nump:").append(num); x*!*2{
buff.append(",results:").append ai<K6)
e6>[Z C
(results); QFB2,k6jN
buff.append("}"); _VB;fH$
return buff.toString(); 4j}.=u* X7
} @X2 zIFm
?AVnv(_
} bN&DotG
:*vSC: q
_}gfec4o