Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 n;LjKE
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 e.WKf,e"X
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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 k
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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 M{g.x4M@W
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分页支持类: -tA_"q'^
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java代码: ART0o7B
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package com.javaeye.common.util; aU*}.{<!
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import java.util.List; 1#9PE(!2
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publicclass PaginationSupport { " c+$GS
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publicfinalstaticint PAGESIZE = 30; CA5T3J@vAQ
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privateint pageSize = PAGESIZE; ]3~u @6
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privateList items; C;~LY&=
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privateint totalCount; [I}z\3Z
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privateint[] indexes = newint[0]; DFvGc`O4
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privateint startIndex = 0; b[J0+l\!"
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public PaginationSupport(List items, int Yl=-j
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totalCount){ yMt:L)+
setPageSize(PAGESIZE); I&`aGnr^^
setTotalCount(totalCount); _bt9{@)
setItems(items); l,Fn_zO
setStartIndex(0); fL*+[v4
} }<zbx*!
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public PaginationSupport(List items, int xQl}~G]!
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totalCount, int startIndex){ n6G&c4g<"
setPageSize(PAGESIZE); 2@IL
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setTotalCount(totalCount); %cBOi_}}~
setItems(items); iNc!zA4
setStartIndex(startIndex); Yr>0Qg],
} b1;h6AeL
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public PaginationSupport(List items, int ?Qx4Z3n
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totalCount, int pageSize, int startIndex){ P-<1vfThH
setPageSize(pageSize);
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setTotalCount(totalCount); _%Yi^^
setItems(items); kP'm$+1or
setStartIndex(startIndex); p:W{c/tV
} 5nTcd@lX
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publicList getItems(){ *Ms&WYN-
return items; I;n<)
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} 5{#s<%b.
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publicvoid setItems(List items){ [$td:N
*
this.items = items; jo3(\Bq
} u-tD_UIck
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publicint getPageSize(){ 9hssIZO
return pageSize; KuW>^mF(I
} )FPn_p#3]
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publicvoid setPageSize(int pageSize){ #eX<=H]
this.pageSize = pageSize; |KVVPXtq%C
} 8I Ip,#%v
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publicint getTotalCount(){ UWhJkJsX
return totalCount; 'IT]VRObP
} ~ch%mI~
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publicvoid setTotalCount(int totalCount){ &=kb>*
if(totalCount > 0){ }"SqB{5e(
this.totalCount = totalCount; wX_~H*m?
int count = totalCount / Ftd,dqd
9|[uie
pageSize; bub6{MQW8e
if(totalCount % pageSize > 0) zG8g}FrzG;
count++; NqGSoOjIO2
indexes = newint[count]; 8!HB$vdw7
for(int i = 0; i < count; i++){ cx ("F/Jm
indexes = pageSize * h&n1}W+
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i; ~I9o* cq
} "RM\<)IF
}else{ 7=5eLc^
this.totalCount = 0; T\(k=0RM
} ,I ][
} >]&Ow9-
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publicint[] getIndexes(){ :Ocw+X3
return indexes; [~X&J#
} Z[ &d2'
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publicvoid setIndexes(int[] indexes){ $zU%?[J
this.indexes = indexes; e$2P/6k>
} O1)\!=&
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publicint getStartIndex(){ sHMO9{[7H
return startIndex; VumM`SH
} k#u)+e.'
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publicvoid setStartIndex(int startIndex){ 0xO*8aKT
if(totalCount <= 0) n\V7^N
this.startIndex = 0; /nu z_y\J
elseif(startIndex >= totalCount) ,hT.Ok={36
this.startIndex = indexes k`A39ln7wu
-%gEND-AP
[indexes.length - 1]; eO(U):C2
elseif(startIndex < 0) hqlQ-aytS
this.startIndex = 0; A0U9,M
else{ 2ZEGE+0
this.startIndex = indexes erbk(
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[startIndex / pageSize]; =6O*AJ
} -ucgET`
} 8D,*_p
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publicint getNextIndex(){ QxGcRlpLK
int nextIndex = getStartIndex() + %[s%H)e)
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pageSize; Wz"H.hf
if(nextIndex >= totalCount) Kop(+]Q&n
return getStartIndex(); h3&|yS|
else Crg'AB?
return nextIndex; ?w'86^_z
} xy4+
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publicint getPreviousIndex(){ K1BBCe
int previousIndex = getStartIndex() - ciiI{T[Z
'21gUYm
pageSize; )wCNLi>4
if(previousIndex < 0) T_=WX_h $
return0; )7.DF|A
else &e;Qabwxva
return previousIndex; Ox&G
[
} .-/IV^lGv
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} >:> W=
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抽象业务类 3X1 1Gl
java代码: u:2Ll[ eo
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/** +kQ=2dva
* Created on 2005-7-12 |\?u-O3
*/ fFqYRK
package com.javaeye.common.business; G$MEVfd"
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import java.io.Serializable; &JqaIJh
import java.util.List; 1ONkmVtL
oD9n5/ozo
import org.hibernate.Criteria; nH k^trGm
import org.hibernate.HibernateException; QAp]cE1ew
import org.hibernate.Session; I4?oBq
import org.hibernate.criterion.DetachedCriteria; A$5M.
import org.hibernate.criterion.Projections; @`:X,]{
import SeDk/}/~e
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org.springframework.orm.hibernate3.HibernateCallback; 4fC:8\A
import ]lBCK
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org.springframework.orm.hibernate3.support.HibernateDaoS J:glJ'4E
)3:0TFS}}k
upport; _3yG<'f[Y
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import com.javaeye.common.util.PaginationSupport; &4S2fWx
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public abstract class AbstractManager extends n*=#jL
pF8 #H~
HibernateDaoSupport { o5?Y
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privateboolean cacheQueries = false; @:9Gs!!
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privateString queryCacheRegion; R8Vf6]s_
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publicvoid setCacheQueries(boolean ikV;]ox
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cacheQueries){ Q}L?o
this.cacheQueries = cacheQueries; yW=+6@A4
} C$1W+(
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publicvoid setQueryCacheRegion(String >- \bLr
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queryCacheRegion){ K8&;B)VT>
this.queryCacheRegion = % (y{Sca
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queryCacheRegion; A,c XN1V
} qGV_oa74
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publicvoid save(finalObject entity){ Fds
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getHibernateTemplate().save(entity); =oq8SL?bJ*
} lt&(S)
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publicvoid persist(finalObject entity){ +wmG5!%$|
getHibernateTemplate().save(entity); P8,Ps+
} 4>>=TJ!M
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publicvoid update(finalObject entity){ ^0OP&s;"
getHibernateTemplate().update(entity); bTaKB-
} i9DD)Y<
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publicvoid delete(finalObject entity){ \MOwp@|y
getHibernateTemplate().delete(entity); j,+]tHC-
} ]$[sfPKA
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publicObject load(finalClass entity, V^5d5Ao
k_=yb^6[U
finalSerializable id){ Ptv'.<-
return getHibernateTemplate().load T+F]hv'
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(entity, id); Tn#Co$<
} *(F`NJ 3
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publicObject get(finalClass entity, 6`e7|ilh6
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finalSerializable id){ rTIu'
return getHibernateTemplate().get 6(f'P_*
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(entity, id); Y#ZgrziYM
} [7FG;}lB-
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publicList findAll(finalClass entity){ qJrT
return getHibernateTemplate().find("from c>B1cR
:x*)o+
" + entity.getName()); IT_I.5*A2
} :eVZ5?F
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publicList findByNamedQuery(finalString @i1e0;\
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namedQuery){ "%gsGtS
return getHibernateTemplate eyCZ[SC
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().findByNamedQuery(namedQuery); pa[/6(
} ~P1~:AT
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publicList findByNamedQuery(finalString query, Hsf::K x
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finalObject parameter){ E^axLp>(I
return getHibernateTemplate 8Y?M:^f~
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().findByNamedQuery(query, parameter); 'rcqy1-&
} v3I^81
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publicList findByNamedQuery(finalString query, "+F'WCJ-(*
y>P+"Z.K%}
finalObject[] parameters){ $oK&k}Q
return getHibernateTemplate *|fF;-#v
+(3_V$|Dv
().findByNamedQuery(query, parameters); ::|~tLFu
} g"! (@]L!@
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publicList find(finalString query){ /o;M
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return getHibernateTemplate().find t<!;shH,s
j~Aq-8R=
(query); kOYUxr.b
} 4+RR`I8$Ge
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publicList find(finalString query, finalObject M3pE$KT0x
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parameter){ pjWRd_h.
return getHibernateTemplate().find Yq+1kA
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(query, parameter); 7>JTQ CJ
} d~LoHp
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public PaginationSupport findPageByCriteria ]:|B).
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(final DetachedCriteria detachedCriteria){
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return findPageByCriteria &|/_"*uM
L8VOiK=,
(detachedCriteria, PaginationSupport.PAGESIZE, 0); ;o_F<68QP
} !(GyOAb
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public PaginationSupport findPageByCriteria Y}:~6`-jj
k{}> *pCU
(final DetachedCriteria detachedCriteria, finalint gxv^=;2C
m\L`$=eO8
startIndex){ JE?rp1.
return findPageByCriteria 3e_tT8
/Nf{;G!kg
(detachedCriteria, PaginationSupport.PAGESIZE, }aZuCe_
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startIndex); b(iF0U>&
} )kpEcMlR
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public PaginationSupport findPageByCriteria u^"
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(final DetachedCriteria detachedCriteria, finalint d1<";b2Jt^
-50DGA,K6
pageSize, Hr|f(9xA
finalint startIndex){ <^5!]8*O
return(PaginationSupport) 2{-29bq
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getHibernateTemplate().execute(new HibernateCallback(){ ^#9385
publicObject doInHibernate X0lPRk53(
$%y q[$^
(Session session)throws HibernateException { ;tjOEmIiU
Criteria criteria =
"o5]:]h)
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detachedCriteria.getExecutableCriteria(session); hsC T:1i
int totalCount = ]juPm8eF
X3.zNHN5
((Integer) criteria.setProjection(Projections.rowCount Fc~G*Gz~Z|
nf.Ox.kM)
()).uniqueResult()).intValue(); -@pjEI
criteria.setProjection B~p%pTS+
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(null); FlqGexY5
List items = @!sK@&ow@%
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criteria.setFirstResult(startIndex).setMaxResults @(t3<g
=+zDE0Qs
(pageSize).list(); uzYB`H<
PaginationSupport ps = VmS_(bM
|7qt/z
new PaginationSupport(items, totalCount, pageSize, iQ'*QbP'Z
pRd.KY -<
startIndex); yPN '@{ 5#
return ps; I652Fcj
} ^/f~\#R
}, true); 7EJ2 On
} &d_^k.%y
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public List findAllByCriteria(final HK;NR.D
K"#$",}=
DetachedCriteria detachedCriteria){ (Ou%0
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return(List) getHibernateTemplate
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l A ^1}
().execute(new HibernateCallback(){ b9bIvjm_
publicObject doInHibernate M5dYcCDE
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(Session session)throws HibernateException { bZqTT~'T
Criteria criteria = J=g)rd[`
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detachedCriteria.getExecutableCriteria(session); zF1!a
return criteria.list(); Abc{<4 z0?
} [9m3@Yd'
}, true); FK%b@/7s~
} G@]3EP
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public int getCountByCriteria(final Jj4HJ9
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DetachedCriteria detachedCriteria){ @\K[WqF$$q
Integer count = (Integer) vsY?q8+P
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getHibernateTemplate().execute(new HibernateCallback(){ ~6G
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publicObject doInHibernate &7L7|{18
@X==[gQ
(Session session)throws HibernateException { q+ax]=w
Criteria criteria = :U6`n
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detachedCriteria.getExecutableCriteria(session); h4Crq Yxa_
return ?uWUs )9
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criteria.setProjection(Projections.rowCount vy<W4
+|A`~\@N
()).uniqueResult(); J'44j;5&
} 56v G R(
}, true); OVg&?fiP
return count.intValue(); ;%tFi
} odv2 (\
} S
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用户在web层构造查询条件detachedCriteria,和可选的 kAftW
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 Myq8`/_
DT-VxF6 h
PaginationSupport的实例ps。 `4Yo-@iVP
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ps.getItems()得到已分页好的结果集 ejN/U{)jK'
ps.getIndexes()得到分页索引的数组 u`bD`kfT>
ps.getTotalCount()得到总结果数 'eM0i[E+`
ps.getStartIndex()当前分页索引 JEUU~L;
ps.getNextIndex()下一页索引 A5<t> 6Y
ps.getPreviousIndex()上一页索引 fBS a8D3}`
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 DiJLWXs
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 VotC YJ
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一下代码重构了。 9+ 'i(q
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我把原本我的做法也提供出来供大家讨论吧: ,\4]uZ<
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首先,为了实现分页查询,我封装了一个Page类: <WXVUEea
java代码: x,B] J4
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/*Created on 2005-4-14*/ y`I>|5[`
package org.flyware.util.page; +%dXB&9x|Z
> 0^<<=m
/** '|8dt "C
* @author Joa <jh4P!\&j
* MN?aPpr>
*/ uwwR$
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publicclass Page { [F-R*}&x
xyL"U*
/** imply if the page has previous page */ Z.VKG1e}
privateboolean hasPrePage; tv#oEM9esl
kK&w5'
/** imply if the page has next page */ m:@y_:X0
privateboolean hasNextPage; 8Qv s\TY
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/** the number of every page */ Wjb_H
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privateint everyPage; R)NSJ-A!2
!%>RHh[
/** the total page number */ { _9O4 +
&
privateint totalPage; =?5)M_6)
FnvpnU",
/** the number of current page */ GJ9>i)+h;
privateint currentPage; PTe L3L
*X0>Ru[
/** the begin index of the records by the current | {9<%Ok4P
abo=v<mR
query */ .}IW!$
dq
privateint beginIndex; eL3 _Lz
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H|%J"
/** The default constructor */ {npm9w<;
public Page(){ :=Olp;+_
*,\v|]fc
} IO)B3,g
9q'9i9/3d
/** construct the page by everyPage "U\RN
* @param everyPage UtQj<18<
* */ <)7aNW.
public Page(int everyPage){ 4'QX1p
this.everyPage = everyPage; uw;Sfx,s
} VF`!ks
fyQOF ItM
/** The whole constructor */ (b25g!
public Page(boolean hasPrePage, boolean hasNextPage, sN41Bz$q.
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B;k'J:-"
int everyPage, int totalPage, 8(1*,CJQg
int currentPage, int beginIndex){ sfF ~k-
this.hasPrePage = hasPrePage; ~I||"$R
this.hasNextPage = hasNextPage; @KQ>DBWQM
this.everyPage = everyPage; EI_-5Tt RD
this.totalPage = totalPage; 1 Pk+zBJ$
this.currentPage = currentPage; ~P3b5 -
this.beginIndex = beginIndex; BH:A]#_{
} (`(D
$%
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/** :nx+(xgw
* @return jVff@)_S
* Returns the beginIndex. Kg%9&l
*/ P:{Aqn~zR
publicint getBeginIndex(){ WvfP9(-
return beginIndex; (*S<2HN5
} Am,{Fj
+?J N_aR
/** )Zq'r L<
* @param beginIndex ciS +.%7
* The beginIndex to set. $nt&'Xnv
*/ {irc0gI
publicvoid setBeginIndex(int beginIndex){ 0'o[2,
this.beginIndex = beginIndex; <h -)zI
} ZJDV'mC}
q`xc h[H
/** v>8.TE~2
* @return {4g';
* Returns the currentPage. 3x~7N
*/ P~a@{n*8
publicint getCurrentPage(){ Q(& @ra!{
return currentPage; Ark]>4x>
} qPDNDkjDD
Xb"i/gfxt
/** eoiz]L
* @param currentPage 5,Fq:j)MxW
* The currentPage to set. Skr(C5T
*/ r#zcl)rbU
publicvoid setCurrentPage(int currentPage){ wAHuPQ&_Q
this.currentPage = currentPage; C.?^] Y
} n]g"H
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/** jg]KE8(
* @return h*Fv~j'p
* Returns the everyPage. ?lC>E[
*/ 6kAAdy}ck
publicint getEveryPage(){ =@U5/J
return everyPage; ,U""m7
} J
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+La2-I
/** uE1;@Dm+
* @param everyPage )+N{D=YM
* The everyPage to set. o;@~uU
*/ pX&bX_F{
publicvoid setEveryPage(int everyPage){ (OiV IH
this.everyPage = everyPage; CnZ!b_J
} cN@_5
2;gvo*k
/** TtkHMPlm_
* @return kL DpZ{
* Returns the hasNextPage. d88A.Z3w
*/ 9~hW8{#
publicboolean getHasNextPage(){ 8&JB_%Gb
return hasNextPage; y i$+rPF1
} |enLv12Gm
w"{DLN[Qw
/** LK} g<!o(
* @param hasNextPage 6Z|h>H5a
* The hasNextPage to set. 3dN`Q:1R9
*/ p7QZn.,=u
publicvoid setHasNextPage(boolean hasNextPage){ t=B1yvE"
this.hasNextPage = hasNextPage; |%|03}Q
} p_I^7 $
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/** v>keZZOs
* @return yksnsHs}d
* Returns the hasPrePage. NgTB4I8P
*/ +,,(8=5g
publicboolean getHasPrePage(){ /4T6Z[=s
return hasPrePage; @ T^FOTW
} xX-r<:'tmi
Krae^z9R
/** Ao\P|K9MyL
* @param hasPrePage %,WH*")
* The hasPrePage to set. GL?b!4xx
*/ 5Npxs&Ea
publicvoid setHasPrePage(boolean hasPrePage){ ]hV!lG1_
this.hasPrePage = hasPrePage; UOb`@#
}
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1^|#QMT
/** Hs)Cf)8u
* @return Returns the totalPage. ?z>J7 }w*=
* DKf(igw
*/ j""ZFh04
publicint getTotalPage(){ 4x6n,:;
return totalPage; *QQeK#$s
} /0}Z>iK
x=cucZ
/** 6 J>A U
* @param totalPage 4'z)J1M
* The totalPage to set. V8/4:Va7s
*/ SMrfEmdH+
publicvoid setTotalPage(int totalPage){ q=pRe-{
this.totalPage = totalPage; jJIP $
} N# }A9t
+j{Cfv$do
} =!t;e~^8]
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M%
~vz%I^xW
TVNgj.`+u!
%tP*_d:
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 Q0(6n8i
Srx:rUCv
个PageUtil,负责对Page对象进行构造: x|m9?[
!_
java代码: >
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2PAu>}W*
/*Created on 2005-4-14*/ `,'/Sdr
package org.flyware.util.page; >e {1e
q;,lv3I
import org.apache.commons.logging.Log; bkd`7(r
import org.apache.commons.logging.LogFactory; SE\?8cs]-
d3:GmB .
/** ,!_6X9N-h
* @author Joa hdDT'+
* '4uu@?!dVk
*/ i2Wvu3,D3-
publicclass PageUtil { b*Y Wd3
@Fc:9a@
privatestaticfinal Log logger = LogFactory.getLog US$$ADq
P] *x6c^n
(PageUtil.class); f|,Kh1{e
wPM&N@Pf
/** s)- ;74(
* Use the origin page to create a new page wj6u,+
* @param page Hk*1Wrs*
* @param totalRecords e' M&Eh
* @return Imv#7{ndq
*/ @$jV"Y
publicstatic Page createPage(Page page, int l$&~(YE f
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totalRecords){ F6}RPk\=i
return createPage(page.getEveryPage(), t~(jA9n
./ {79
page.getCurrentPage(), totalRecords); Kn:Ml4[;
} #DgHF*GG+>
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/** 94-BcN
* the basic page utils not including exception +4-T_m/W/
Nbr$G=U
handler 4fsd5#
* @param everyPage 'yPKQ/y$x
* @param currentPage l(NQk> w
* @param totalRecords XSC=qg$
* @return page 3q'AgiW
*/ d~~kJKK
publicstatic Page createPage(int everyPage, int e4` L8
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currentPage, int totalRecords){ e%[*NX/
everyPage = getEveryPage(everyPage); At\(/Zy
currentPage = getCurrentPage(currentPage); 1<G+KC[F
int beginIndex = getBeginIndex(everyPage, x.-d)]a!
l\W|a'i
currentPage); RKP,w%
int totalPage = getTotalPage(everyPage, jae9!Wi
/-p!|T}w
totalRecords);
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boolean hasNextPage = hasNextPage(currentPage, 14 & KE3`
^i%S}VK
totalPage); GS>[A b+
boolean hasPrePage = hasPrePage(currentPage); Ip'tB4Mq
]i#p2?BR
returnnew Page(hasPrePage, hasNextPage, h&i*=&<HP6
everyPage, totalPage, yIL=jzm`7
currentPage, O=3/qs6m
\I!mzo
beginIndex); JVuju$k
} m}'_Poc
XX/gS=NE#.
privatestaticint getEveryPage(int everyPage){ \Sd8PGl*'
return everyPage == 0 ? 10 : everyPage; ]$ "eGHX
} 8NHm#Z3Ol
^+76^*0
privatestaticint getCurrentPage(int currentPage){ @N4~|`?U
return currentPage == 0 ? 1 : currentPage; .v+JV6!u
} 2#7|zhgb
Zkd{EMW
privatestaticint getBeginIndex(int everyPage, int \o!3TK"N
#`u}#(
currentPage){ 96^aI1:
return(currentPage - 1) * everyPage; lndz
} N_T5sZ\
~`AB-0t.u
privatestaticint getTotalPage(int everyPage, int w~u{"E$
dQ8RrD=$&
totalRecords){ U:TkO=/>:
int totalPage = 0; {T-\BTh&Q
Qx4)'n
if(totalRecords % everyPage == 0) :gV~L3YW5
totalPage = totalRecords / everyPage; kumV|$Y?kA
else FY'0?CT$
totalPage = totalRecords / everyPage + 1 ; _<c"/B
ARu_S
B
return totalPage; s-IE}I?;
} ts~VO`
{\(G^B*\
privatestaticboolean hasPrePage(int currentPage){ C*2%Ix18+N
return currentPage == 1 ? false : true;
^f,4=-
} !Axe}RD'
!}!KT(%%
privatestaticboolean hasNextPage(int currentPage, :C_/K(Rkl
D
5r H6*J
int totalPage){ i%9vZ
return currentPage == totalPage || totalPage == m ~&
<'4Wne.z!
0 ? false : true; D;!sH?J@+
} kD#n/RBgf
W+i^tmj
c6[m'cy
} st)is4
q8$t4_pF
"0!h-bQN
ATkd# k%S
9Rk(q4.OP
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 >.qFhO\1so
iLnW5yy
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 i?/Q7D<P
^^v3iCT
做法如下: zls^JTE
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 zdwQpB,+^
@m5J%8>k
的信息,和一个结果集List: WVeNO,?ytS
java代码: Yd3lL:M
iTinZ!Ut
fJ/INL
/*Created on 2005-6-13*/ j9k:!|(2'
package com.adt.bo; STwGp<8
&MpLm&
import java.util.List; gg`{kN^r.a
pl>b 6 |
import org.flyware.util.page.Page; {O>Td9
9^!.!%6O$
/** 9YI@c_1 Q
* @author Joa ;((t|
*/ 'KjH|u
publicclass Result { QT+kCN
US)i"l7:H*
private Page page; us.[wp'Sh
C[,h!
private List content; \Hp!NbnF$
_9=87u0
/** ug]2wftlQ
* The default constructor fR[8O\U~
*/ ;:=j{,&dl[
public Result(){ _AF$E"f@
super(); a>vxox) %
} 2e\"?y OD
$?F_Qsy{d
/** IrZjlnht
* The constructor using fields YA,.C4=s
* jP<6J(
* @param page 8d*S9p,/
* @param content r#WqXh_uk
*/ Oey
Ph9^V
public Result(Page page, List content){ >aJmRA-C}
this.page = page; C@*x
this.content = content; e r_6PV
} 6|p8_[e`
jlb8<xIC]
/** _i ztQ78
* @return Returns the content. p8 S~`fjV
*/ 0i}.l\
publicList getContent(){ bDDP:INm.
return content; Y"t|0dO%b
} (^~a1@f,J
K_+M?ap_
/** <,DMD
* @return Returns the page. w(bvs&`{uC
*/ F7<M{h5s
public Page getPage(){ +On2R&m
return page; imADjBR]
} 1CJ1-]S(3
pzRVX8
/** jy~hLEt7
* @param content NCg("n,jx
* The content to set. YN)qMI_`A
*/ >0SG]er@
public void setContent(List content){ |34k;l]E
this.content = content; 2.nT k
} IgJG,!>h
|d&Kr0QIV
/** c*#$sZ@YA
* @param page d0T 8Cwcb
* The page to set. x(>XM:|
*/ jA^yUd-
publicvoid setPage(Page page){ N#-%b"(
this.page = page; -5e8m4*
} L2Cb/!z`c
} !]R>D{""
B0RVtbK
v "2A?
MX*4d{ l
A
PSkW9H
2. 编写业务逻辑接口,并实现它(UserManager, ,&,XcbJ
9/8+R%
UserManagerImpl) V9ZM4.,OCN
java代码: 6 [bQ'Ir^8
i=^6nwD&
UK'8cz9
/*Created on 2005-7-15*/ (Qw >P42J
package com.adt.service; !*DYdqQ/
Jm=3%H
import net.sf.hibernate.HibernateException; @=g{4(zR^
DCa=o
import org.flyware.util.page.Page; ;]R5:LbXS
KKk<wya&O
import com.adt.bo.Result; Y A+R!t:F{
d?5oJ'JU
/** 2 .Xx)(>
* @author Joa ;|\j][A
*/ nIOSP:'>
publicinterface UserManager { ~W"@[*6w
`<@ "WSn
public Result listUser(Page page)throws e2%mD.I
0f_`;{
HibernateException; GS>YfJ&DZ
.5SYN-@
} @(6P L^I
_TdH6[9
v"Bm4+c&0
gr!!pp;
uu-M7>+
java代码: 0WZd $
^[I>#U
yz>S($u
/*Created on 2005-7-15*/ 1.,KN:qe
package com.adt.service.impl; t\:=|t,
<2O#!bX1
import java.util.List; y'6l fThT
|d\1xTBLp
import net.sf.hibernate.HibernateException; ME>Sh~C\
n[;)(
import org.flyware.util.page.Page; C!K&d,M
import org.flyware.util.page.PageUtil; Y ajAz5N
( ?e
Et&
import com.adt.bo.Result; LGtw4'yr
import com.adt.dao.UserDAO; ]w*` }
import com.adt.exception.ObjectNotFoundException; mDt!b6N/
import com.adt.service.UserManager; ]#S<]v A
18j>x3tn
/** m1K4_a)^[
* @author Joa Z6So5r%wZ
*/ E>|fbaN-%
publicclass UserManagerImpl implements UserManager { giIPK&
wKpD++k
private UserDAO userDAO; @}r
s6 G
Nw,|4S
/** <}xgp[O
* @param userDAO The userDAO to set. qs8^qn0A
*/ ^\S~rW.3_
publicvoid setUserDAO(UserDAO userDAO){ ~4#D
G^5
this.userDAO = userDAO; M`iE'x
} [\ 0>@j}Z
bO('y@)X
/* (non-Javadoc) TQ~a5q
* @see com.adt.service.UserManager#listUser 00-2u~D&
Rw63{b/
(org.flyware.util.page.Page) J`; 9Z
*/ K4RQ{fWpm
public Result listUser(Page page)throws >CcDG
c[3x>f0
HibernateException, ObjectNotFoundException { klc$n07
int totalRecords = userDAO.getUserCount(); L[5U(`q[
if(totalRecords == 0) benqm ~{\
throw new ObjectNotFoundException b!/-9{
%ol1WG 9
("userNotExist"); Y~r)WV!G
page = PageUtil.createPage(page, totalRecords); svt3gkR0
List users = userDAO.getUserByPage(page); [tC=P&<
returnnew Result(page, users); 2h@&yW2j
} ww+,GnV
A&ceuu
} EKuLt*a/
sw:a(o&$
m.gv?
; Ob^@OM
roi,?B_8
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 7 > _vH]
BEAY}P(y3
询,接下来编写UserDAO的代码: 0=9$k
3. UserDAO 和 UserDAOImpl: q&:%/?)x
java代码: McbbEs=)
wZ`*C
mr
fC}uIci
/*Created on 2005-7-15*/ ^mut-@ N9
package com.adt.dao; DHvZ:)aT}
?oV|.LM:W
import java.util.List; &tiJ=;R1
&-My[t
import org.flyware.util.page.Page; tp"eXA0n
1bDXv,nD
import net.sf.hibernate.HibernateException; >C5u>@%9O
k|jr+hmn":
/** .WBp!*4
* @author Joa v@fy*T\3
*/ cQ`0d3
publicinterface UserDAO extends BaseDAO { s?Gv/&
n0 V^/j}
publicList getUserByName(String name)throws Uu Zjf9}
S*7 6V"")
HibernateException; +'VYqu/
HqyAo]{GN
publicint getUserCount()throws HibernateException; JZ>
(h
\nTV;@F
publicList getUserByPage(Page page)throws s._,IW;
g">^#^hBE
HibernateException; {=,I>w]T|W
+KTHZpp!c2
} .jbxA2
CFoR!r:X
alsD TQ'
\IqCC h
n7/&NiHxv/
java代码: >$a;+v
g<$2#c}
I;UT;/E2
/*Created on 2005-7-15*/ Q^xk]~G$(
package com.adt.dao.impl; m G+=0Rn^
"kVzN22
import java.util.List; [e{W:7uFV
*.T?#H
import org.flyware.util.page.Page; )tS;gn
R`Hy0;X
import net.sf.hibernate.HibernateException; <33,0."K
import net.sf.hibernate.Query; mO8/eVws[M
/*M3Ns1@2
import com.adt.dao.UserDAO; aej'c bO
yGV>22vv
M
/** gr@Ril^
* @author Joa I;G(Wj
*/ j^hLn>
public class UserDAOImpl extends BaseDAOHibernateImpl 7y.iXe!P
ao|n<*}
implements UserDAO { e3[Q6d&|
{/,AMJ<:G]
/* (non-Javadoc) z"Cyjmg"
* @see com.adt.dao.UserDAO#getUserByName O{U j
`'pAiu
(java.lang.String) a#9pN?~
*/ Y|tK19
publicList getUserByName(String name)throws #]gmM
AYp~;@
HibernateException { q_9 tbZ;
String querySentence = "FROM user in class NQvI=R-g
DhsvN&yNM
com.adt.po.User WHERE user.name=:name"; )ac!@slb^7
Query query = getSession().createQuery LPca+o|f
|TR
+Wn
(querySentence); @:>gRD
query.setParameter("name", name); qmvQd8|XR
return query.list(); N\rL ~4/
} MGre_=Dm_
G68@(<<Z
/* (non-Javadoc) ;=6EBP%
* @see com.adt.dao.UserDAO#getUserCount() ,^DP
*/ *O_^C
publicint getUserCount()throws HibernateException { 3Y&4yIx
int count = 0; =([4pG
String querySentence = "SELECT count(*) FROM dt"&
_,d<9 Y)
user in class com.adt.po.User"; &rl;+QS
Query query = getSession().createQuery roBb8M|q
~_g{P3
(querySentence); @S>;t)\J
count = ((Integer)query.iterate().next Ap4.c8f?Q-
| :id/
()).intValue(); )%lPKp4]
return count; {2i8]Sp1d/
} K%Bz6 ~
V\l@_%D[(v
/* (non-Javadoc) "7jE&I
* @see com.adt.dao.UserDAO#getUserByPage 4GXS(
<z>oY2%
(org.flyware.util.page.Page) :)&vf<JL
*/ $TK= :8HY
publicList getUserByPage(Page page)throws a(ml#-M
pUW7p
HibernateException { ;BKU
_}k=
String querySentence = "FROM user in class cL~YQJYp
@g]EY&Uzl
com.adt.po.User"; @X560_x[q
Query query = getSession().createQuery f$vTD ak
k1s5cg=n(
(querySentence); 9jM7z/Ff
query.setFirstResult(page.getBeginIndex()) @7V~CNB+
.setMaxResults(page.getEveryPage()); >VX'`5r>uw
return query.list(); ZE~zs~z|
} GQQp(%T
:F@goiuC
} A
r>BL2@
=q`T|9v
"^;h'
.0~uM!3y
i$<")q
至此,一个完整的分页程序完成。前台的只需要调用 ou<,c?nNM
Nd{U|k3pL
userManager.listUser(page)即可得到一个Page对象和结果集对象 a;M{-G
Fop +xR,Z
的综合体,而传入的参数page对象则可以由前台传入,如果用 ,LxkdV
TU*EtE'g/
webwork,甚至可以直接在配置文件中指定。 bX`Gv+
/SQ/$`1{
下面给出一个webwork调用示例: KC9e{
java代码: ?)(-_N&T
#N'9
w .
.aVt d
[
/*Created on 2005-6-17*/ 3dolrW
package com.adt.action.user; Re
%dNxJ=
Jyr
V2Tk^
import java.util.List; .`V$j.a
%H2ios[UO
import org.apache.commons.logging.Log; o
P;6i
import org.apache.commons.logging.LogFactory; &g1\0t
import org.flyware.util.page.Page; a6 0rJ#GD
Mw)6,O`
import com.adt.bo.Result; cUdS{K&K
import com.adt.service.UserService; J_m@YkK
import com.opensymphony.xwork.Action; $ ]#WC\Hv
As`=K$^Il.
/** n${k^e-=
* @author Joa r\Yh'cRW{
*/
KLE)+|
publicclass ListUser implementsAction{ Jmi,;Af'/
c %Cbq0+2
privatestaticfinal Log logger = LogFactory.getLog HEIg_6sb
*f`P7q*
(ListUser.class); \g
h |G
_L$a[zH
private UserService userService; 2CneRKQy
0Oc?:R'$
private Page page; $(]nl%<Q
X{OWDy
privateList users; ws^Ne30 R
' VKD$q
/* :."oWqb)
* (non-Javadoc) n+te5_F
* jlFlhj:/I
* @see com.opensymphony.xwork.Action#execute() wJCw6&D,/
*/ 6N5(DD
publicString execute()throwsException{ 1 <+aF,
Result result = userService.listUser(page); +}a(jO
page = result.getPage(); '%XYJr:H[
users = result.getContent(); "J=Cy@SSa
return SUCCESS; isQOt *
i
} Hq 3V+$
OE9,D:tv
/** }2Euz.0
* @return Returns the page. n-yUt72
*/ tp>YsQy]8
public Page getPage(){ 19#>\9*
return page; #Lp}j?Y
} 0<NS1y
4OpzGZ4+
/** MGt>:&s(]
* @return Returns the users. 6=;(~k&x9:
*/ ck5cO-1>6
publicList getUsers(){ c@3 5\!9
return users; [|=M<>?[
} =DDKGy.g
nReld
:#T
/** ?_Z-}f
* @param page RLB"}&SF]
* The page to set. dIlpo0; F
*/ ||awNSt
publicvoid setPage(Page page){ bvB',yBZ
this.page = page; =\5WYC
} G[yzi
t^FE]$,
/** fx[&"$X
* @param users V<jj'dZfW
* The users to set. %oTBh* K'o
*/ x5BS|3W$a
publicvoid setUsers(List users){ HbsNF~;
this.users = users; Opc szq5n
} TnK<Wba
V3q`V/\
/** hRu}P"
* @param userService $5)#L$!,]
* The userService to set. NimgU Fa
*/ (EY@{'.&
publicvoid setUserService(UserService userService){ MyllL@kP
this.userService = userService; 0#!}s&j/
}
Y6VJr+Ap(
} A#T"4'#?<
L'?aoRj
M-Efe_VRQc
L%is"NZh
>RkaFcq
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, 8X"4RyNSn
cOX )+53
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 wTU$jd1;+
sIgTSdk
么只需要: ]B=*p0~j^n
java代码: T:X*
O& Sk}^
aq}hlA(w
<?xml version="1.0"?> d4;$=P
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork PR:B6 F8
A+* lV*@0
1.0//EN" "http://www.opensymphony.com/xwork/xwork- Mh-"B([Z
Sl,DZ!
1.0.dtd"> jc
Mn
o?>0WSLlm
<xwork> ]$r]GVeN}H
#xGP|:m
<package name="user" extends="webwork- j;]I
-M[
!~~KM?g
interceptors"> RdWn =;
\EVT*v=}/
<!-- The default interceptor stack name x,25ROaHY
y
2>
93m
--> Y^!qeY
<default-interceptor-ref SefhOh^,V
Kgr<OL}V J
name="myDefaultWebStack"/> *pa hZiO
Q:megU'u
<action name="listUser" }
u;{38~
oOpEpQ}}q
class="com.adt.action.user.ListUser"> lt6wmCe
<param ue@/o,C>
9S@x
name="page.everyPage">10</param> #&Tm%CvB
<result /g{*px|
="& GU%$
name="success">/user/user_list.jsp</result> 5.{=Op!
</action> AYfOETz
Cy$~H
</package> 81{8F
49=pB,H;H
</xwork> }={@_g#
hHJvLs>^
k4LrUd
}vZf&ib-
-J+1V{
~iH a^i?2*
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 :a;F3NJ
it\$Pih]
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 O~V^]
q<q IT
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 yO%^[c?
?m]vk|>
Dnw^H.
XYWyxx5`
%eDSo9Y
我写的一个用于分页的类,用了泛型了,hoho by
@q g:
VtLRl0/
java代码: @rbd`7$%
k37?NoT
p]RQ-0
package com.intokr.util; &SbdX
';FJs&=I
import java.util.List; wz`% (\
piM4grg
\
/** V*\hGNV
* 用于分页的类<br> S}JOS}\^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> l}L81t7f
* Pq [_(Nt
* @version 0.01 DfAF-Yhut
* @author cheng tJ;qZyy(
*/ A)]&L`s
public class Paginator<E> { 9
fB|e|
privateint count = 0; // 总记录数 '9f0UtT|[
privateint p = 1; // 页编号 >va_,Y}
privateint num = 20; // 每页的记录数 =fRS UtX
privateList<E> results = null; // 结果 aJ(/r.1G
9lYfII}4(
/** 0"OEOYs}
* 结果总数 Qpmq@iL
*/ ny13+Q`^
publicint getCount(){ .S54:vs
return count; ]?VVwft
} m*_X PY
rah"\f2
publicvoid setCount(int count){ .?6p~
this.count = count; #b[bgxm
} ,.9 lz
bfz7t!A)A
/** ~
q-Z-MA
* 本结果所在的页码,从1开始 C7{VByxJ
* SDC|>e9i
* @return Returns the pageNo. Mn
,hmIz
*/ >1!u]R<3
publicint getP(){ G%bv<_R
return p; J "I,]
} 8S8qj"s
#b;?:.m\=
/** zz
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L
* if(p<=0) p=1 gP
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* Mrrpm%Y
* @param p sr;&/l#7h
*/ >ZOlSLu
publicvoid setP(int p){ BQPmo1B
if(p <= 0) gaz7u8$A=
p = 1; }2;P`s
this.p = p; b69nj
} N0w?c 5>
O +o)z6(
/** FM6{%}4
* 每页记录数量 ^.LB(GZ,
*/ 95'+8*YCY
publicint getNum(){ {`SMxDevc}
return num; :
b`N(]
} O`y3H lc
GL O3v.
n;
/** -b^dK)wR~
* if(num<1) num=1 es6YxMg
*/ e}?Q&Lci
publicvoid setNum(int num){ bfA>kn0C
if(num < 1) Qg/FFn^Kg*
num = 1; j<kW+Iio
this.num = num; Am*IC?@tq
} B%\&Q@X
_\\Al v.
/** I;'{X_9$a
* 获得总页数 Nt$4;
*/ ]YI9
publicint getPageNum(){ eX#.Zt]
return(count - 1) / num + 1; &qg6^&
} CPy>sV3Ru0
>)M1X?HI5
/** &/UfXKr
* 获得本页的开始编号,为 (p-1)*num+1 &YY`XEG59O
*/ ;:bp?(
publicint getStart(){ 3&})gU&a
return(p - 1) * num + 1; GxzO|vFQ
} Aeh#
.*`^dt
/** I4@XOwl{P
* @return Returns the results. 1@OpvO5
*/ ,1~zYL?
publicList<E> getResults(){ d?X,od6
return results; fr(Ja;
} X?t;uZI^
8
*f9
public void setResults(List<E> results){ 5.VPK 338A
this.results = results; eaf-_#qb
} ]#G s6CsT|
}
TUr96
public String toString(){ oVK:A;3T|
StringBuilder buff = new StringBuilder a,oTU\m
C
PoaCnoNS
(); vU%K%-yXG7
buff.append("{"); ;w .la
buff.append("count:").append(count); D@&xj_#\}
buff.append(",p:").append(p); TQck$&
buff.append(",nump:").append(num); !nl-}P,
buff.append(",results:").append %@C8EFl%3
@LOfqQ$FE
(results); *>W<n1r@]
buff.append("}"); .;7V]B1o
return buff.toString(); fd *XK/h
} R-m5(
%/I:r7UR{
} ;l!<A
3H!]X M
i_N8)Z;r