Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 3$S~!fh
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 D#A6s32a
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 (3~^zwA
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 NFF!g]QN
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。
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分页支持类: [=",R&uD$
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java代码: oJQ
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package com.javaeye.common.util; =K_&@|f+B
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import java.util.List; xz,o Mlw
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publicclass PaginationSupport { T0~~0G)k
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publicfinalstaticint PAGESIZE = 30; W23Q>x&S
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privateint pageSize = PAGESIZE; TV#>x!5!d
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privateList items; Kr[oP3
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privateint totalCount; G4rzx%W?
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privateint[] indexes = newint[0]; ]s!id[j
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privateint startIndex = 0; M6bM`wHH>
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public PaginationSupport(List items, int 5E*Qqe
{> <1K6t
totalCount){ |sY
setPageSize(PAGESIZE); 5S,Kq35$(
setTotalCount(totalCount); T
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setItems(items); O#t[YP
setStartIndex(0); R7K`9 c1f6
} ;xiwyfqgE
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public PaginationSupport(List items, int ~)n[Vf
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totalCount, int startIndex){ K&zW+C b
setPageSize(PAGESIZE); N&eo;Ti
setTotalCount(totalCount); ?@7!D8$9
setItems(items); K&RIF]0#G
setStartIndex(startIndex); <h;_:
} ![nL/
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public PaginationSupport(List items, int QqRF?%7q"q
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totalCount, int pageSize, int startIndex){ <QO1Yg7}
setPageSize(pageSize); e&*b{>1*
setTotalCount(totalCount); Jm#p!G+
setItems(items); /qMnIo
setStartIndex(startIndex); M@P%k`6C
} K~2sX>l
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publicList getItems(){ NL>Trv5
return items; H(tC4'tA
} KO%$
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publicvoid setItems(List items){ ExSM=
this.items = items; =.&8ghJ*M
} dvqg H
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publicint getPageSize(){ 9P)!v.,T/
return pageSize; ?o$t{AQ
} ?|/K(}
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publicvoid setPageSize(int pageSize){ Kw$@_~BJ6
this.pageSize = pageSize; T/2k2r4PD
} E?czolNl
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publicint getTotalCount(){ hczDu8
return totalCount; pgiZA?r*<
} Ez"*',(
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publicvoid setTotalCount(int totalCount){ n6.Z{Q'b
if(totalCount > 0){ 8h }a:/
this.totalCount = totalCount; A%?c1`ZxF
int count = totalCount / s~2o<#
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pageSize; RXg\A!5GV
if(totalCount % pageSize > 0) |>.MH
count++; Hg<aU*o;
indexes = newint[count]; :9ia|lN
for(int i = 0; i < count; i++){ w8R7Ksn(
indexes = pageSize * wdfbl_`T
)W>$_QxbN
i; A[^#8evaK
} nOd;Zw
}else{ y0(.6HI
this.totalCount = 0; cW_wIy\]&
} Yl>Y.SO
} aJf3rHX
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publicint[] getIndexes(){ !j`<iPI7B
return indexes; >6jal?4u-
} "_\"S
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publicvoid setIndexes(int[] indexes){ PP!-*~F0Jr
this.indexes = indexes; CDuA2e
} N`?/kubD
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publicint getStartIndex(){ EVaHb;
return startIndex; (jyufHm
} (=c,b9cb
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publicvoid setStartIndex(int startIndex){ 2T(+VeMQ=
if(totalCount <= 0) &&LB0vH!J
this.startIndex = 0; )Qe]!$tqfD
elseif(startIndex >= totalCount) mPQT%%MF
this.startIndex = indexes {=Jo!t;f
oq$#wiV"Q
[indexes.length - 1]; ewdTsgt'
elseif(startIndex < 0) ]yqE6Lf9
this.startIndex = 0; *
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else{ ,~1k:>njY~
this.startIndex = indexes Piwox1T;
,!%E\`
[startIndex / pageSize]; emrA!<w!W
} "sDs[Lcq
} lP]Y^Gz
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publicint getNextIndex(){ z9OpxW@Ou
int nextIndex = getStartIndex() + z8{-I@+`
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pageSize; b30Jr2[
if(nextIndex >= totalCount) $Q'z9ghEg
return getStartIndex(); X9FO"(J
else 4L{]!dox
return nextIndex; kMnG1K
} U{pg
y#/
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publicint getPreviousIndex(){ `0M6<e]C
int previousIndex = getStartIndex() - )b2O!p
n9J{f"`m
pageSize; +5Dc5Bl
if(previousIndex < 0) Xfqin4/jC
return0; Mb\(52`)Q
else t[X^4bZd
return previousIndex; /JC1o&z_T
} a9{NAyl<oo
<)(W7#Ks
} z,SI
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抽象业务类 x`@`y7(
java代码: "qR, V9\
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/** g9VY{[V
* Created on 2005-7-12 =G^'wwpv(
*/ $*%,
package com.javaeye.common.business; #(Gz?kGAH`
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import java.io.Serializable; '#LzQ6Pn
import java.util.List; h{ix$Xn~
N AY3.e
import org.hibernate.Criteria; FE,mUpHIR
import org.hibernate.HibernateException; Gvh"3|u?z
import org.hibernate.Session; =IQ}Y_xr
import org.hibernate.criterion.DetachedCriteria; "zd_eC5
import org.hibernate.criterion.Projections; r#)1/`h
import Is}kCf
; xp-MK
org.springframework.orm.hibernate3.HibernateCallback;
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import =|IlORf<
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org.springframework.orm.hibernate3.support.HibernateDaoS BPt? 3tC
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upport; F/>\uzu
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import com.javaeye.common.util.PaginationSupport; SKnYeT
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public abstract class AbstractManager extends =%IyR
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HibernateDaoSupport { GVnDN~[
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privateboolean cacheQueries = false; eU%49 A
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privateString queryCacheRegion; 04;s@\yX4
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publicvoid setCacheQueries(boolean ^OWG9`p+
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cacheQueries){ UiH7
this.cacheQueries = cacheQueries; Zc1x"j
} *1`X}
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publicvoid setQueryCacheRegion(String iUR ij@
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queryCacheRegion){ vFR*3$R
this.queryCacheRegion = Jk\-e`eE
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queryCacheRegion; T*C25l;w
} H2R3I<j
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publicvoid save(finalObject entity){ t
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getHibernateTemplate().save(entity); 8ex;g^e
} PZ8,E{V
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publicvoid persist(finalObject entity){ \M\7k5$
getHibernateTemplate().save(entity); <L qJg
} ~ `qWEu
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publicvoid update(finalObject entity){ [%dsq`b#
getHibernateTemplate().update(entity); [h;I)ug[o(
} CipDeqau2
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publicvoid delete(finalObject entity){ !9/`PcNIpy
getHibernateTemplate().delete(entity); xo'!$a}I2
} lY
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publicObject load(finalClass entity, /y-D_
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finalSerializable id){ ;(`bP
return getHibernateTemplate().load d0I s|Gs
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(entity, id); *FC8=U2\X
} SQcic]Ep
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publicObject get(finalClass entity, lUEbxN
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finalSerializable id){ KUZi3\p9W>
return getHibernateTemplate().get <9fXf*
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(entity, id); :wIA.1bK}
} wz:e\ !
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publicList findAll(finalClass entity){ }?Y -I>
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return getHibernateTemplate().find("from jJiuq#;T3
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" + entity.getName()); [l5jPL}6
} 2v ~8fr4
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publicList findByNamedQuery(finalString K _VIk'RB
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namedQuery){ pE<a:2J
return getHibernateTemplate 8m
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().findByNamedQuery(namedQuery); cwzkA,e@
} x!GDS>
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publicList findByNamedQuery(finalString query, PM84Z@Y
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finalObject parameter){ Zb1GR5MB`k
return getHibernateTemplate }kmAUaa,Z
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().findByNamedQuery(query, parameter); _)5E=
} im&N&A
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publicList findByNamedQuery(finalString query, i_*yS+Z;
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finalObject[] parameters){ 5"nq
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return getHibernateTemplate @~hy'6/
m=9b/Nr4
().findByNamedQuery(query, parameters); n+=qT$w)
} _\+]/rY9o
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publicList find(finalString query){ .c]>*/(+
return getHibernateTemplate().find PzKTEYJL
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(query); FA-cTF[,(
} ZskX!{
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publicList find(finalString query, finalObject p}pRf@(`\
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parameter){ 2EM6k|l5
return getHibernateTemplate().find <1I4JPh>x
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(query, parameter); ddN(L`nd
} [(*Eg!?W=
}@6Ze$>
public PaginationSupport findPageByCriteria k
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5?H8?~&dz
(final DetachedCriteria detachedCriteria){ BmpAH}%T
return findPageByCriteria 9oc_*V0<
vai w*?jV
(detachedCriteria, PaginationSupport.PAGESIZE, 0); \l(J6Tu
} u4FD}nV
+:^l|6%}
public PaginationSupport findPageByCriteria mTu>S
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(final DetachedCriteria detachedCriteria, finalint '8)kFR^9
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startIndex){ Y910\h@V
return findPageByCriteria 0#TL$?=|
[(Z(8{3i
(detachedCriteria, PaginationSupport.PAGESIZE, f$:Y'$Z1
A{\?]]/
startIndex); 3 orZBT
} QBGm)h?=
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public PaginationSupport findPageByCriteria }.045 Wuu
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(final DetachedCriteria detachedCriteria, finalint stK}K-=`
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pageSize, 9NwUXh(:(
finalint startIndex){ F<{,W-my `
return(PaginationSupport) |HT7m5tu4
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getHibernateTemplate().execute(new HibernateCallback(){ s?;8h &]=
publicObject doInHibernate o} QP+
roc DO8f
(Session session)throws HibernateException { plPPf+\
Criteria criteria = _D}3``
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detachedCriteria.getExecutableCriteria(session); eEBNO*2
int totalCount = <vWP_yy
c=+%][21
((Integer) criteria.setProjection(Projections.rowCount J:W+'x`@
fx+_;y
()).uniqueResult()).intValue(); )B
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criteria.setProjection RK-bsf
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(null); 0IqGy}+VU
List items = Gn4b*Y&M]3
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criteria.setFirstResult(startIndex).setMaxResults D"aK;_W@h
eY#^vB
(pageSize).list(); I)1ih
PaginationSupport ps = }0\SNpVN
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new PaginationSupport(items, totalCount, pageSize, %XN;S29d5W
r
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startIndex); `},:dDHI
return ps; hd'fWFWN
} mZB:j]T
}, true); Q e+;BE-H
} jj2=|)w$3
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public List findAllByCriteria(final mD7NQ2:wA
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DetachedCriteria detachedCriteria){ y "+'4:_
return(List) getHibernateTemplate #2i$:c~
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().execute(new HibernateCallback(){ j?*n@'
publicObject doInHibernate w^8Q~3|7
Q 8Ek}O\MC
(Session session)throws HibernateException { BMO,eQcB
Criteria criteria = }iDRlE,
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detachedCriteria.getExecutableCriteria(session); 0
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return criteria.list(); (BtU\f#d
} MVzj7~+
}, true); {J1rjrPo
} XM!oN^
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public int getCountByCriteria(final :tO?+1
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DetachedCriteria detachedCriteria){ vcy1itY
Integer count = (Integer) u,iiS4'Ze
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getHibernateTemplate().execute(new HibernateCallback(){ B /3~[ '
publicObject doInHibernate X~m57bj
W20- oZ8
(Session session)throws HibernateException { *-]k([wV
Criteria criteria = ApSseBhh
+7OE,RoQ
detachedCriteria.getExecutableCriteria(session); _5n2'\] H`
return ?z M
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criteria.setProjection(Projections.rowCount 0P$19TN
]b}3f<
()).uniqueResult(); >h2qam
} o"RE4s\G~r
}, true); F !v01]O
return count.intValue(); Us "G X_
} u*iqwm.
} Kg2@]J9m
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n @@tO#!\
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>/.jB/q
用户在web层构造查询条件detachedCriteria,和可选的 E.$//P n|1
uq:'`o-1
startIndex,调用业务bean的相应findByCriteria方法,返回一个 >Gg[J=7`
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PaginationSupport的实例ps。 <5]_u:
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ps.getItems()得到已分页好的结果集 b,HXD~=
ps.getIndexes()得到分页索引的数组 -=rGN"(M
_
ps.getTotalCount()得到总结果数 c?xeBC1-
ps.getStartIndex()当前分页索引 !Y^$rF-+
ps.getNextIndex()下一页索引
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ps.getPreviousIndex()上一页索引 N]c:8dOj
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 <N80MUL|
#lVSQZO~a
,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 :]C\DUBo
2(D&jL
一下代码重构了。 84Hm
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我把原本我的做法也提供出来供大家讨论吧: #@5 jOi
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首先,为了实现分页查询,我封装了一个Page类: wAb_fU&*
java代码: r:^`005
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/*Created on 2005-4-14*/ e8]mdU{)
package org.flyware.util.page; JR_c]AQYu
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/** wVs |mG"
* @author Joa HoM8V"8B
* }% |GV
*/ 9>@"W-
publicclass Page { 0Zl1(;hx@
483vFLnF
/** imply if the page has previous page */ \=~<I
privateboolean hasPrePage; CV7.hF<
M9S[{Jj*
/** imply if the page has next page */ ]zK} X!
privateboolean hasNextPage; [
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{la^useg[
/** the number of every page */ :Ws3+OI'm3
privateint everyPage; &jPsdv h
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/** the total page number */ ~yf 5$~Z
privateint totalPage; EA>$t\z
DFjkp;`1
/** the number of current page */ }#u}{
privateint currentPage; CnA*o 8w
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/** the begin index of the records by the current ZNA?`Z)f
m
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query */ pV-.r-P
privateint beginIndex; Cw^)}23R
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/** The default constructor */ *'t`;m~
public Page(){ 1Q;`<=
FRF}V@~
} p9sxA|O=y
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/** construct the page by everyPage _bz,G"w+:
* @param everyPage ?%0i,p@<
* */ BR%: `uiQ<
public Page(int everyPage){ r#~6FpFVK^
this.everyPage = everyPage; nW%c95E
} 1Q$ M/}
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/** The whole constructor */ q.X-2jjpx:
public Page(boolean hasPrePage, boolean hasNextPage, M*{e e0\`r
V7v,)a" L
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int everyPage, int totalPage, V)Xcn'h
int currentPage, int beginIndex){ Stw6%T-
this.hasPrePage = hasPrePage; 3G&1. 8
this.hasNextPage = hasNextPage; /kq~*s
this.everyPage = everyPage; x[kdQj2[&
this.totalPage = totalPage; %~[F^
this.currentPage = currentPage; cS[`1y,\3
this.beginIndex = beginIndex; u!S{[7 FY
} @'y"D
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/** /4f;Niem
* @return GgYomR:
* Returns the beginIndex. 7> Qt O
*/ w$!n8Aqs
publicint getBeginIndex(){ &_6:TqJ
return beginIndex; +Lr0i_al
} 6bn-NY:i
_Owz%
/** IR&u55#I6
* @param beginIndex *%e#)sn*
* The beginIndex to set. 57}q'84
*/ \CGcP
publicvoid setBeginIndex(int beginIndex){ A!~o?ej
this.beginIndex = beginIndex; ]=3O,\
} ;sf/tX
6M9rC[h\
/** {1+H\(v
* @return Mg$Z^v|}0
* Returns the currentPage. one>vi`=
*/ m @%|Q;
publicint getCurrentPage(){ 2o/`8+eJu
return currentPage; SJ-Sac58r
} ;~J~g#
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/** =!X4j3Cv
* @param currentPage v(O.GhJ@
* The currentPage to set. a6d KQ3D
*/ luT8>9X^:a
publicvoid setCurrentPage(int currentPage){ h(-&.Sm")H
this.currentPage = currentPage; %U7B0-
} <GN?J.B
p rgjU
/** fLAF/#\2
* @return 4;||g@f'[
* Returns the everyPage. d#Ajb
*/ I\~V0<"jI
publicint getEveryPage(){ C.-a:oQ[
return everyPage; @\?f77Of6
} @UJmbD{
]r6bJ2
/** v"+EBfx
* @param everyPage ~~,<+X:
* The everyPage to set. #8jd,I%L
*/ F948%?a
publicvoid setEveryPage(int everyPage){ ]o$/xP
this.everyPage = everyPage; beE%%C]X
} m5N&7qgp
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/** 8)8oR&(f
* @return [@Y q^.6t
* Returns the hasNextPage. [)~@NN
*/ qGCg3u6
publicboolean getHasNextPage(){ I/jr`3Mj
return hasNextPage; RzQS@^u*F0
} ~*[4DQ[\
V bOLTc
/** -d'|X`^nE
* @param hasNextPage <v k$eB8EC
* The hasNextPage to set. ^6>|!
*/ ycD.:w p\'
publicvoid setHasNextPage(boolean hasNextPage){ f*}E\,V"&
this.hasNextPage = hasNextPage; J94YMyOo
} l$_rA~Mo
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/** L"%eQHEC&
* @return mp3_n:R?
* Returns the hasPrePage. L$Ar]O)
*/ zqr%7U
publicboolean getHasPrePage(){ 5O
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return hasPrePage; #`0z=w/)
} g8A{aHb1}
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/** fcXk]W
* @param hasPrePage 9?chCO(@
* The hasPrePage to set. $ywh%OEH
*/ %MZDm&f>Kk
publicvoid setHasPrePage(boolean hasPrePage){ G;c0
this.hasPrePage = hasPrePage; mIEaWE;E"
} q<[ke
9k[},MM
/** s^'#"`!v=
* @return Returns the totalPage. 00a<(sS;
* Prz+kPP
*/ -G#@BtB2+
publicint getTotalPage(){ )"jn{%/t
return totalPage; 42wC."A
} Z)T@`B6
?mfWm{QTt
/** TxxB0
* @param totalPage {&u7kWD|
* The totalPage to set. ^1yTL5#:Vw
*/ <;0N@
publicvoid setTotalPage(int totalPage){ &t|V:_?/x
this.totalPage = totalPage; _QUu'zJ
} \ +-hn
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|9k
} A+1]Ql)$
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4\SBf\ c
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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 bo !]
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个PageUtil,负责对Page对象进行构造: AH87UkNL
java代码: o7a6 )2JK
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Q()RO*9
/*Created on 2005-4-14*/ ^r$iN %&~
package org.flyware.util.page; Nk7e iQ
:;*#Qh3"
import org.apache.commons.logging.Log; W*rU,F|9
import org.apache.commons.logging.LogFactory; Q'Kik5I
Re,$<9V
/** 9H, &nET
* @author Joa E,D:D3O
* G<^]0`"+)t
*/ 6n6VEwYj
publicclass PageUtil { s3_e7D ^H
1s}NQ3
privatestaticfinal Log logger = LogFactory.getLog V3A>Ag+^~
fzFvfMAU
(PageUtil.class); :CkR4J!m3
<X I35\^
/** YK?*7
* Use the origin page to create a new page p-'6_\F.Ke
* @param page Xlqz8cI
* @param totalRecords eFj6p<
* @return ADv"_bB:h
*/ Neo^C_[vN
publicstatic Page createPage(Page page, int ,7fc41O3V
F@K*T2uh
totalRecords){ #?$'nya*u
return createPage(page.getEveryPage(), @X|i@{<';
(XG[_
page.getCurrentPage(), totalRecords); Q{l*62Bx
} rTsbP40
+{C9uY)$vf
/** l@tyg7CwY
* the basic page utils not including exception Yf!*OGF
J%\~<_2ny
handler 16[-3cJ T
* @param everyPage >: W-C{%
* @param currentPage zOiY0`=
* @param totalRecords ?lc[hH
* @return page o1#:j?sN
*/ hM36QOdm
publicstatic Page createPage(int everyPage, int $['7vcB^
iO9nvM<
currentPage, int totalRecords){ Yt/SnF
everyPage = getEveryPage(everyPage); I| W'n-4Y
currentPage = getCurrentPage(currentPage); hSkc9jBF
int beginIndex = getBeginIndex(everyPage, [j=,g-EOA
Pn+IJ=0Y
currentPage); Tbi]oB#
int totalPage = getTotalPage(everyPage, $/, BJ/9
0j{F^rph
totalRecords); @QVqpE<|
boolean hasNextPage = hasNextPage(currentPage, mZbWRqP[|_
t":W.q<
totalPage); dcl.wD0~V
boolean hasPrePage = hasPrePage(currentPage); 'nlRY5@2
,W1a<dl
returnnew Page(hasPrePage, hasNextPage, m1hW<
everyPage, totalPage, |-(IJG#)
currentPage, N>A{)_k3
Ue{vg$5||
beginIndex); ${eY9-r_%
} C5PmLiOHY>
=mHkXHE~:
privatestaticint getEveryPage(int everyPage){ `%t$s,TiP
return everyPage == 0 ? 10 : everyPage; T|o`a+?
} UTDcX
.1.J5>/n
privatestaticint getCurrentPage(int currentPage){ i\=z'
return currentPage == 0 ? 1 : currentPage; G}!7tU
} >
$w^%I
{J,6iP{>ZN
privatestaticint getBeginIndex(int everyPage, int b&lN%+%}
0W T#6D
currentPage){ :vc[/<
return(currentPage - 1) * everyPage; XYqpI/s
}
SwdC,
!;o\5x<'$O
privatestaticint getTotalPage(int everyPage, int .O5LI35,
AVXX\n\_
totalRecords){ La"o)L +m_
int totalPage = 0; _\
.
R*s* +I
if(totalRecords % everyPage == 0) v!NB~"LQ
totalPage = totalRecords / everyPage; Q~fwWp-J
else ! jbEm8bt
totalPage = totalRecords / everyPage + 1 ; 5/& 1Oxo
cPpu
return totalPage; g3|BE2?
} n?'d|h
rr |"r
privatestaticboolean hasPrePage(int currentPage){ )46
0Ed
return currentPage == 1 ? false : true; <jbj/Q )"
} }qc#lz
P3'2IzNw
privatestaticboolean hasNextPage(int currentPage, dCB&c^
ds-
yif6
int totalPage){ Y)$52m5rM
return currentPage == totalPage || totalPage == @ Nb%L&=P8
*IZf^-=Q
0 ? false : true; (vQ+e
} ut5yf$%
5f{|"LG&
Qb`C)Nh:
} "s]y!BLk
FFe)e>bH
&qRJceT(
g-@h>$<
1
EXpSh}
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 iZ;TYcT
R]QpMj%o
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 G;]:$J
N[k<@Q?*a
做法如下: k'+}92
o
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 mU G
%LM
TnE+[.Qu
的信息,和一个结果集List: ;V.vfar
java代码: U:lv^QPG
Sz0+<F#5
]k+m=OR{/
/*Created on 2005-6-13*/ z $6JpG
package com.adt.bo; RJc%,
]:
dr})-R
import java.util.List; km\%BD~
Eark)
import org.flyware.util.page.Page; #*,sa
59!)j>f
/** 8tQ|-l*
* @author Joa 4}yE+dRUK:
*/ `Q%NSU?
publicclass Result { X?dfcS*!n
T1NH eH>
private Page page; /iC_!n u
cZ<
\
private List content; '29WscU
Hg(5S,O2
/** Q4K+*Fi}
* The default constructor :ba/W&-d
*/ 5py R~+
public Result(){ lbkLyp2
super(); Z?1OdoT-
} 3N<&u
<abKiXA"
/** s~$zWx@v
* The constructor using fields L[C*@
uK
* <t}? $1
* @param page mk= #\>
* @param content 3j*'HST
*/ #nEL~&
public Result(Page page, List content){ )zJ=PF
this.page = page; knSuzq%*
this.content = content; 9X]f [^
} MY F#A
)w"0w(
/** ;.s:X
* @return Returns the content. /DU*M,
*/ 9#@Zz4Ww
publicList getContent(){ Z[}
$n-V
return content; afm_ Rrg[
} -,GEv%6c
Qp!J:YV
/** x!?Z*v@I
* @return Returns the page. F]5\YYXO
*/ x/ I;nMY
public Page getPage(){ q^Inb)FeN
return page; <SQ(~xYi
} a8JN19}D
j9xXKa5
/** %F5 =n"
* @param content RgGA$HN/
* The content to set. F=i!d,S
*/ kCp)!hVQ
public void setContent(List content){ *V|zx#RN
this.content = content; q\H7&w
} $4Y&j}R
e?<D F.Md+
/** 1Z:R,\+L
* @param page h5!d
* The page to set. -f.R#J$2
*/ b *9-}g:
publicvoid setPage(Page page){ c[{UI
this.page = page; t/ eo]
} ~4 ^p}{
} {!t=n
q^6N+ ^}QN
!4B_$6US
kY!C_kFcn
s3< F
2. 编写业务逻辑接口,并实现它(UserManager, `,Zb2"
oCA(FQ6
UserManagerImpl) SG`)PW?
java代码: YFqZe6g0$
VN+\>j-
@g\;` #l
/*Created on 2005-7-15*/ %~\
package com.adt.service; WRM$DA
?cxr%`E
import net.sf.hibernate.HibernateException; I61%H9;
:rL?1"
import org.flyware.util.page.Page; GLcd9|H
>[P%Ty);
import com.adt.bo.Result; 4cB&Hk
2L[l'}
/** @<5Tba>SC
* @author Joa [' t8C
*/
G1p'p&x.
publicinterface UserManager { Um'Ro 4
:iEA UM
public Result listUser(Page page)throws 4y>(RrVG
ZM
8U]0[X
HibernateException; b-uZ"Kf^
%-r?=L
} D&f!( n
R9r)C{63S&
ki4Xp'IK
N-Z^G<[q.
HT-PWk>2
java代码: sL8>GtVo
VH<e))5C
)r pD2H
/*Created on 2005-7-15*/ H\d;QN9Q;
package com.adt.service.impl; B6uRJcD4
w_!%'9m>
import java.util.List; ( mt*y]p?
{yU0D*#6
import net.sf.hibernate.HibernateException; /D8EI
[brkx3h
import org.flyware.util.page.Page; s" N\82z)
import org.flyware.util.page.PageUtil; o
Fi) d[`
IE}Sdeqi)
import com.adt.bo.Result; FF jRf
import com.adt.dao.UserDAO; b(1:w"wD
import com.adt.exception.ObjectNotFoundException; g kn)V~ij
import com.adt.service.UserManager; s4N,^_j
w?i)/q
/** Eny!R@u7q
* @author Joa q6Rw4
*/ yduuFK
publicclass UserManagerImpl implements UserManager { }\EL;sT
7<vy;"wB
private UserDAO userDAO; $q^O%(
i!tc
/** >I|<^$/
* @param userDAO The userDAO to set. c|+y9(0|y
*/ b70AJe=
publicvoid setUserDAO(UserDAO userDAO){ Pm~,Ky&Hl
this.userDAO = userDAO; q{[1fE"[K4
} E~}[+X@
3#B@83C0Z
/* (non-Javadoc) X&/(x
* @see com.adt.service.UserManager#listUser ~RAzFLt6x
8z?$t-D O
(org.flyware.util.page.Page) w gmWo8
*/ UYH|?Jw!N
public Result listUser(Page page)throws ";o~&8?)
7WXiG0
HibernateException, ObjectNotFoundException { + 2OZJVJ
int totalRecords = userDAO.getUserCount(); ?,!uA)({n
if(totalRecords == 0) V@Ax}<$A
throw new ObjectNotFoundException DhHtz.6
9OH.&g
("userNotExist"); ta@ISRK
page = PageUtil.createPage(page, totalRecords); LMt0'Ml9
List users = userDAO.getUserByPage(page); `Y0fst<,
returnnew Result(page, users); y)0gJP
L^
} g^qz&;R]
1xq3RD
} cl?<
7
=P1RdyP
{ 576+:*
)j]gm i"
`^?}s-H+
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ,G/\@x%
?f(pQy@V
询,接下来编写UserDAO的代码: |~7+/VvI+
3. UserDAO 和 UserDAOImpl: @?'t@P:4
java代码: Z83q-
&8pCHGmV)
[lmHXf@1C
/*Created on 2005-7-15*/ MA~|y_V
package com.adt.dao; VaOpO8y`
nh _DEPMq
import java.util.List; Gw{Gt]liq
7qCJ]%)b6
import org.flyware.util.page.Page; !%SdTaC{T
ho?|j"/7
import net.sf.hibernate.HibernateException; 0sq=5 BnO
g(ZeFOn
/** x.j Yip
* @author Joa 6n2Vx1b
*/ ;u4@iN}p
publicinterface UserDAO extends BaseDAO { jx^|2
Y&ct+w]%
publicList getUserByName(String name)throws 0"wbcAh)
T4%i`<i
HibernateException; Xq=!"E
{hW
+^
publicint getUserCount()throws HibernateException; r6gt9u:
eONeWY9
publicList getUserByPage(Page page)throws "1gk-
\NvC
HibernateException; .{'Uvn
o$[a4I
} C,sD?PcSi+
=]5DYRhX]
$S($97IU=
HJ2]Nz:
0-;DN:>
java代码: qd#(`%_/
=F^->e0N
S*2L4Uj`|
/*Created on 2005-7-15*/ Knw'h;,[
package com.adt.dao.impl; 1pYmtr
~P"!DaAf
import java.util.List; Mc#O+'](f
,J`lr
U0
import org.flyware.util.page.Page; u~naVX\3b
clR?< LO
import net.sf.hibernate.HibernateException; M&}oat*
import net.sf.hibernate.Query; A
.jp<>
:?&WKW
import com.adt.dao.UserDAO; c4qp3B_w
NbQMWU~7
/** &bS"N)je
* @author Joa buCm @@o
*/ yp^[]Mz=
public class UserDAOImpl extends BaseDAOHibernateImpl k_En_\c?p2
<g/(wSl
implements UserDAO { CL<KBmW7
]`/R("l[
/* (non-Javadoc) ^ T:qT*v
* @see com.adt.dao.UserDAO#getUserByName 2=!3[>
B
c=jI.=mi3
(java.lang.String) :>er^\
*/ HhY2`P8
publicList getUserByName(String name)throws @dT: 1s
v,!Y=8~9
HibernateException { iEJQ#5))0
String querySentence = "FROM user in class hI>rtaY_
kb}]sj
com.adt.po.User WHERE user.name=:name"; 3<UDVt@0
Query query = getSession().createQuery Q
2SSJ
~d#;r5>
(querySentence); qeK
query.setParameter("name", name); =Zb"T5E
return query.list(); @L>NN>?SGQ
} .'NO~
G(|(y=ck
/* (non-Javadoc) K+\0}qn
* @see com.adt.dao.UserDAO#getUserCount() 1A/c/iC
*/ )zL"r8si
publicint getUserCount()throws HibernateException { |>/&EElD
int count = 0; [;V1y`/K1
String querySentence = "SELECT count(*) FROM c[d'1=Qiy
,0<F3h
user in class com.adt.po.User"; >y06s{[
Query query = getSession().createQuery vA7jZw
TLL[F;uZ
(querySentence); XdIVMXLL\
count = ((Integer)query.iterate().next M@2Qn-I
"JUQ)> !?
()).intValue(); |>o0d~s
return count; |<Dx
} L};;o+5uJD
ga1gd~a
/* (non-Javadoc) }$k`[ivBx(
* @see com.adt.dao.UserDAO#getUserByPage J&U0y
v`ZusHJ1d
(org.flyware.util.page.Page) kx:lk+Tx
*/ ?o(X0
publicList getUserByPage(Page page)throws `@.s!L(V
Sp$x%p0
HibernateException { uSQ>oi]
String querySentence = "FROM user in class \`%Y-!H+v
=!P?/
com.adt.po.User"; LX?r=_\
Query query = getSession().createQuery `=l{kBZT|
n\ ',F
(querySentence); aaD$'Y,<>B
query.setFirstResult(page.getBeginIndex()) r5qx! >
.setMaxResults(page.getEveryPage()); Q3O .<9S
return query.list(); ONe!'a0
} w3bH|VnU8;
Gx* 0$4xJ3
} k| cI!
llG#nDe
?kFCYZK|"
S{)n0/_
oY6|h3T=Q$
至此,一个完整的分页程序完成。前台的只需要调用 lnC Wu@{
gsR9M%mv
userManager.listUser(page)即可得到一个Page对象和结果集对象 _NqT8C4C
|>}0? '/]
的综合体,而传入的参数page对象则可以由前台传入,如果用 -r'seb5
|{LaZXU &
webwork,甚至可以直接在配置文件中指定。 `"b7y(M
pD6g+Taj
下面给出一个webwork调用示例: m#K%dR
java代码: {2clOUi
u,,WD
rJQ|Oi&1i
/*Created on 2005-6-17*/ d?y\~<
package com.adt.action.user; SWO!E
4x?u5L
9o
import java.util.List; ?[/,*Q%
x Bw.M{
import org.apache.commons.logging.Log; zYF&Dv/u/
import org.apache.commons.logging.LogFactory; Wy>\KrA1
import org.flyware.util.page.Page; (C|V-}/*m
UMW^0>Z!v
import com.adt.bo.Result; PH%gX`N
import com.adt.service.UserService; .LcE^y[V
import com.opensymphony.xwork.Action; R{A/+7!
}e=GvWGa
/**
9QZ wUQ
* @author Joa ayz1i:Q|
*/ /r@
publicclass ListUser implementsAction{ 7#.PMyK9
58'y~Ou
privatestaticfinal Log logger = LogFactory.getLog k#NMD4(%O
}M@Jrq+7
(ListUser.class); 3^yWpSC
N%E2BJ?
private UserService userService; *LdH/C.LIf
'c(Y")QP
private Page page; Awf=yE:
Z@O
e}\.$
privateList users; ;OqLNfU3y
#f;1f8yrN
/* zn$Ld,
* (non-Javadoc) ]JuB6o_L
* k\Tm?^L)
* @see com.opensymphony.xwork.Action#execute() _?LI0iIFx
*/ usf(U>
publicString execute()throwsException{ q[A3$y(
Result result = userService.listUser(page); xi=uXxl
page = result.getPage(); c}s3c
>`d
users = result.getContent(); %~XJwy-
return SUCCESS; \ jdO,-(
} {j*+:Gj0V
-3U}
(cZ*
/** =H?5fT^
* @return Returns the page. ` &7?+s
*/ "z4E|s
public Page getPage(){ |]b/5s;>
return page; )PNk
O3
} 9 NSYrIQ"
W7>_nK+g?
/** 74wa
* @return Returns the users. YP97D n
*/ 3e1"5~?'<
publicList getUsers(){ nwH|Hs riU
return users; #]^`BQ>
} ^@eCT}p{
xF0*q
/** oD`BX
* @param page |8ZAE%/d
* The page to set. zaPR>:r0
*/ w`:KexD+
publicvoid setPage(Page page){ |REU7?B
this.page = page;
rMloj8O*
} 4}j}8y2)H
]z NL+]1_
/** wJ}8y4O!N
* @param users S=Zjdbd
* The users to set. = FQH
*/ `CV a`%
publicvoid setUsers(List users){ QwiC2}/
this.users = users; 4-o$OI>
} zr,jaR;
s=q}XIWK
/** NXV%j},>
* @param userService H>M0GL
* The userService to set. ~jJu*s$?
*/ ~fr1O`8
publicvoid setUserService(UserService userService){ x*(pr5k
this.userService = userService; MYLq2g\
} WWD\EDnS
} :I1bGa&I
y9:|}Vh
bE0cW'6r
N@*v'MEko%
c D7q;|+
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, ?"J5~_U.
,~c:P>v=
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 ?9/%K45
,OG sx
么只需要: sA:0b5_a
java代码:
8DyE
OfIml.
CI
~+(+q
<?xml version="1.0"?> UtY<R
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork _^Rf*G !
}[?X%=
1.0//EN" "http://www.opensymphony.com/xwork/xwork- Ws'3*HAce
pM.>u/=X
1.0.dtd"> I9TOBn|6
^+!!:J|ra
<xwork> *S`&
XPj
'lg6<M%#[
<package name="user" extends="webwork- iwrS>Sm
eCdMDSFO3
interceptors"> -g_PJ.Hk
HP"5*C5D
<!-- The default interceptor stack name |Kh#\d
0vf2wBK'T
--> t d-EB&i\
<default-interceptor-ref ,\xeNUZd
(?;Fnq
name="myDefaultWebStack"/> ^DM^HSm
S"V|BU
<action name="listUser" n:x6bPal]
44]/rP_m
class="com.adt.action.user.ListUser"> 8?J\
<param _T)dmhG
U_B"B;ng+
name="page.everyPage">10</param> [C.Pzo
<result {H=DeQ
L1
O\PEeT
name="success">/user/user_list.jsp</result> d>VerZZU
</action> R=_
fk
T\NvN&h-
</package> 9YwK1[G6/
H3nx8R$j](
</xwork> #EgFB}>1
cL?FloPc*
YP5V~-O/
g#2Q1t,~U
$2~I-[
^`!5!|
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 A|Up>`QH
Zx@/5!_n.
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 ]_G!(`Udh
|W[BqQIf
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 8*k#T\
}lvD 5
1O"7%Pvw
sG!SSRL@
ZaIlo5
我写的一个用于分页的类,用了泛型了,hoho s,!+wHv_8
5|. _K(M
java代码: fRS)YE@a:
5ztHar~f
wH&[Tg
package com.intokr.util; aZ"9)RJe
{y-7xg~}
import java.util.List; 6EfGJq
_?$P?
/** p^S]O\;M7
* 用于分页的类<br> DlIy'@ .
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 6P@3UQ)}s
* ME4Ir
* @version 0.01 'Pyeb`AXE9
* @author cheng unn2MP'
*/ Twi:BI`.
public class Paginator<E> { TNs;#Q
privateint count = 0; // 总记录数 f~nAJ+m=
privateint p = 1; // 页编号 nW?DlECo?
privateint num = 20; // 每页的记录数 u
xi f-5
privateList<E> results = null; // 结果 LU
"e9
a:nMW '!
/** H3<
`
* 结果总数 :"BZK5{8
*/ aI @&x
publicint getCount(){ &Xw{%Rg
return count; PW a!7n#A
} "7Qc:<ww
57:Wh=x
publicvoid setCount(int count){ >9KQWeD
this.count = count; nU]4)t_o\
} ai/VbV'|
|%6zhkoufM
/**
&Uqm3z?v
* 本结果所在的页码,从1开始 uYk4qorA
* 8'c_&\kdv
* @return Returns the pageNo. NUB 3L
*/ 9n][#I)a3
publicint getP(){ Id->F0x0
return p; +;nADl+Q
} \ dpsyc
`a.1Af;L
/** ?R2`RvQ
* if(p<=0) p=1 'MEO?]Tf.^
* 5~WMb6/
* @param p Mk-C'
*/ pfCNFF*"
publicvoid setP(int p){ UMe@[E=
if(p <= 0) +f)Nf)\q
p = 1; F[ca4_lK
this.p = p; X2#;1 ku
} S&BJR!FQ
enu",wC3
/** r{~K8!=oU]
* 每页记录数量 pq;)l(Hi
*/ nLZT3`@~,
publicint getNum(){ ii%n:0+zm
return num; 8e_ITqV%
} ^FLuhLS\*
(0%0+vY
/** ]#hT!VOd
* if(num<1) num=1 gd9ZlHo'Id
*/ m4:b?[
publicvoid setNum(int num){ F*WWv&\X
if(num < 1)
5" U8|
num = 1; /wIev1Z!Y
this.num = num; HaeF`gI^Ee
} Q"]C"?
yc,Qz.+g
/** htg+V-,
* 获得总页数 !:3NPjhf1Y
*/ 8;3T65KY
publicint getPageNum(){ 'Mjbvh4
return(count - 1) / num + 1; bHcb.;<
} * wN+Ak q
!ViHC}:
/** Jrlc%,pZ
* 获得本页的开始编号,为 (p-1)*num+1 6.tppAO+
*/ 5v8&C2Jy@
publicint getStart(){ ]4@z.1Mr
return(p - 1) * num + 1; B\bIMjXV
} ,2?"W8,
*>.~f<V
/** 0-Xpq,0
* @return Returns the results. /= P!9d
{
*/ }/G~"&N[
publicList<E> getResults(){ Zl"h-~31
return results; $ i@5'[jA
} o
<LA2q`T
;3'}(_n
public void setResults(List<E> results){ J8a4.prqI
this.results = results; >'^l>FPc
} $y=sT({VVe
R4}G@&Q
public String toString(){ =fBJQK2sk
StringBuilder buff = new StringBuilder f7OfN#I
Uk ?V7?&
(); Fg4eIE-/M
buff.append("{"); r3ZY`zf
buff.append("count:").append(count); f%*-PW^*
buff.append(",p:").append(p); ) !ZA.sx
buff.append(",nump:").append(num); @tjC{?5Y
buff.append(",results:").append #f/-i u=L
m{Q{ qJ5>
(results); I+O!<SB
buff.append("}"); KUH&_yCRB
return buff.toString(); "_'9KBd!
} U$VTk
XrSqUD
} v}[KVwse
Jc9SHCJ
*/\dH<