Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 _,L_H[FN
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ]!{S2x&"
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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 I:TbZ*vi~
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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 :1*E5pX0n
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分页支持类: "++\6H<
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java代码: ]%A> swCpn
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package com.javaeye.common.util; Nj4CkMM[3
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import java.util.List;
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publicclass PaginationSupport { -fPiHKJ
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publicfinalstaticint PAGESIZE = 30; k 3m_L-
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privateint pageSize = PAGESIZE; (Y)2[j
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privateList items; lk
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I
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privateint totalCount; <8b1OdA
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privateint[] indexes = newint[0]; Np+PUu>
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privateint startIndex = 0; i6KfH\{N
> mO*.'Gm
public PaginationSupport(List items, int pRun5 )7
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totalCount){ Vr},+Rj
setPageSize(PAGESIZE); I*N"_uKU
setTotalCount(totalCount); -NJpql{Cb
setItems(items); t/;0/ql\
setStartIndex(0); |qMG@
} N~=I))i
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public PaginationSupport(List items, int *Mhirz%iD
~".@mubt1$
totalCount, int startIndex){ I.3~ctzu
setPageSize(PAGESIZE); V,rc&97
setTotalCount(totalCount); 9PKXQp
setItems(items); %FYhq:j
setStartIndex(startIndex); 5\pS8<RJ;
} Xeq9Vs zg
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public PaginationSupport(List items, int qhY+<S9
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totalCount, int pageSize, int startIndex){
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setPageSize(pageSize); `*vO8v
setTotalCount(totalCount); l48$8Mgrr
setItems(items); *gwaW!=
setStartIndex(startIndex); 44*#qLN
} 1k6asz^T
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publicList getItems(){ ;"nO'wN:h
return items; eP]y\S*P
} 7.Y;nem:(
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publicvoid setItems(List items){ 'l^Bb#)"
this.items = items; t?>}0\1
} +H3~Infr4f
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publicint getPageSize(){ A:(|"<lA
return pageSize; Vbv^@Kp
} 89:nF#
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publicvoid setPageSize(int pageSize){ w317]-n
this.pageSize = pageSize; rQ*w3F?:
} A.r7 ks
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publicint getTotalCount(){ U6/7EOW,
return totalCount; Jt5V{9:('
} ltuV2.$
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publicvoid setTotalCount(int totalCount){ [`GSc6j
if(totalCount > 0){ PFX,X
this.totalCount = totalCount; r[V%DU$dj
int count = totalCount / &5-1Cd E
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pageSize; +zMhA p
if(totalCount % pageSize > 0) nZB~l=
count++; Ij(<(y{?Q1
indexes = newint[count]; >`03EsU
for(int i = 0; i < count; i++){ P{)D_Bi
indexes = pageSize * g*b`o87PI
-
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i; (@}^ 3jpT
} z~h?"'
}else{ =Oy&f:s
this.totalCount = 0; ywp_,j9F
} ,Sgo_bC/|
} d=bKNA90
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ri
publicint[] getIndexes(){ \YzKEYx+
return indexes; b~&cYk'
} .fzyA5@l
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publicvoid setIndexes(int[] indexes){ Nmx\qJUR(
this.indexes = indexes; `
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} (m2%7f.I
1SjVj9{:
publicint getStartIndex(){ b<y*:(:
return startIndex; y?UJ<QAi
} TI3xt-/
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publicvoid setStartIndex(int startIndex){ 6k0Awcr
if(totalCount <= 0) nX:E(9q7c
this.startIndex = 0; "}_J"%
elseif(startIndex >= totalCount)
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this.startIndex = indexes 1L::Qu%E
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[indexes.length - 1]; 3Y#
elseif(startIndex < 0) c<_1o!68
this.startIndex = 0; h
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else{ *66EkCj
this.startIndex = indexes kKF=%J?X
/b
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[startIndex / pageSize]; kI`HD
} I7Kgi3
} -I{op
wd
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publicint getNextIndex(){ Y&bYaq
int nextIndex = getStartIndex() + gWHY7rv
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pageSize; ?x",VA
if(nextIndex >= totalCount) BywEoS
return getStartIndex(); G h+;Vrx
else ?M4ig_
return nextIndex; UZt3Ua&J
} sRT5i9TQ
<9>L^GgXA
publicint getPreviousIndex(){ xytWE:=
int previousIndex = getStartIndex() - m>Wt'Cc
B>E4,"
pageSize; 7Q{&L#;
if(previousIndex < 0) 4wKCzPy
return0; Fb<'L5}i
else 0(c,J$I]Z!
return previousIndex; &kdW(;`
} S".|j$
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h
} NblPVxS
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抽象业务类 A?HDY_u
java代码: #vK99S2
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/** O~8jz
* Created on 2005-7-12 Wp
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*/ Yw=@*CK'
package com.javaeye.common.business; o&q:b9T
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import java.io.Serializable; `vt+VUNf
import java.util.List; YH^U"\}i
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import org.hibernate.Criteria; _Rjbm'kC
import org.hibernate.HibernateException; 9ox5,7ZQ
import org.hibernate.Session; S9:ij1
import org.hibernate.criterion.DetachedCriteria; y46sL~HRv
import org.hibernate.criterion.Projections; "?aE3$/
import te;bn4~
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org.springframework.orm.hibernate3.HibernateCallback; q) 5s'(
import i|H^&$|
qtVgjT2#H
org.springframework.orm.hibernate3.support.HibernateDaoS 2|!jst
-;Mh|!yg
upport; W"/,<xHuh
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import com.javaeye.common.util.PaginationSupport;
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public abstract class AbstractManager extends ?jO<<@*2S
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HibernateDaoSupport { f~?5;f:E
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privateboolean cacheQueries = false; 'h&>K,U?5
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privateString queryCacheRegion; +tkm,>s
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publicvoid setCacheQueries(boolean I7XM2xM
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cacheQueries){ A\/DAVnI
this.cacheQueries = cacheQueries; IwXQbJ3v_
} )q!dMZ(
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publicvoid setQueryCacheRegion(String sWA-_4
jbOwpyH
queryCacheRegion){ V:D?i#%,z
this.queryCacheRegion = aQWg?,Ju6
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queryCacheRegion; V+'zuX
} R,!aX"]|
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publicvoid save(finalObject entity){ L eUp!
getHibernateTemplate().save(entity); gvjy'Rm
} >0N$R|B&
L!5="s[}
publicvoid persist(finalObject entity){ F ww S[3
getHibernateTemplate().save(entity); sN[<{;K4
} LD|T1.
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publicvoid update(finalObject entity){ ywjD.od"v
getHibernateTemplate().update(entity); 4}Os>M{k
} v{SYz<(
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publicvoid delete(finalObject entity){ /#x0?d{5
getHibernateTemplate().delete(entity); ;cv\v(0
} )1 0aDTlr
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publicObject load(finalClass entity, a$11u.\q+
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finalSerializable id){ }z-)!8vF
return getHibernateTemplate().load (:#4{C
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(entity, id); on\ahk, y]
} B`%%,SLJ
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publicObject get(finalClass entity, {y!77>Q/
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finalSerializable id){ :n}t7+(>U
return getHibernateTemplate().get ltl(SIi
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(entity, id); <~5$<L4
} "Bn]-o|r
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publicList findAll(finalClass entity){ [+dTd2uZ<\
return getHibernateTemplate().find("from ~:4Mf/Ca
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" + entity.getName()); FefS]G
} {M0pq3SL*t
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publicList findByNamedQuery(finalString }PzYt~Z`@
=H^^AG\}
namedQuery){ mhnK{M @56
return getHibernateTemplate W-"FRTI4
P4"EvdV7
().findByNamedQuery(namedQuery); }'TZ)=t{J
} '$CJZ`nt
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publicList findByNamedQuery(finalString query, :B_ itl0{e
'l'[U
finalObject parameter){ aQfrDM<*XS
return getHibernateTemplate ""F'Nzy
0>?78QL9<
().findByNamedQuery(query, parameter); '"Dgov$q
} +(2mHS0_a
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publicList findByNamedQuery(finalString query, A|GheH!t
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finalObject[] parameters){ D)LqkfJ}z^
return getHibernateTemplate CbRl/ 68HY
852Bh'u_
().findByNamedQuery(query, parameters); Qte'f+
} `ZAGseDd~
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publicList find(finalString query){ BBm;QOBU
return getHibernateTemplate().find r \]iw v
wkZ}o,{*:
(query); 6t6#<ts
} !Zf)N_k
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publicList find(finalString query, finalObject -Z%B9ql'
9/S-=VOe.t
parameter){ U_c9T>=
return getHibernateTemplate().find s@bo df&
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(query, parameter); H`ZUI8-
} fNaS?tV)
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public PaginationSupport findPageByCriteria E%C02sI
zpd Z.
(final DetachedCriteria detachedCriteria){ I_@XHhyVZ
return findPageByCriteria iY1JU-S
wp8ocZ-Gj
(detachedCriteria, PaginationSupport.PAGESIZE, 0); hGvuA9d~
} $nbZ+~49
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public PaginationSupport findPageByCriteria w873: =
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(final DetachedCriteria detachedCriteria, finalint "8Y4;lbN.q
lGZ^ 8
startIndex){ A#j'JA>_
return findPageByCriteria p1L8g[\
'PrrP3lO_~
(detachedCriteria, PaginationSupport.PAGESIZE, {wx!~K
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startIndex); IGd]!
} BI-xo}KI
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public PaginationSupport findPageByCriteria L?e N(L
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(final DetachedCriteria detachedCriteria, finalint m[FH>
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pageSize, EBN'u&zX
finalint startIndex){ @9^ozgg
return(PaginationSupport) ~vIQ-|8r:
(1(dL_?
getHibernateTemplate().execute(new HibernateCallback(){ HW(cA}$
publicObject doInHibernate Q<V?rPAcx
*w538Vb
(Session session)throws HibernateException { V'4sOn
Criteria criteria = D?3^>h
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detachedCriteria.getExecutableCriteria(session); Zi fAn
int totalCount = WL<$(y:H
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((Integer) criteria.setProjection(Projections.rowCount C&m[/PJ~l
EI*B(
()).uniqueResult()).intValue(); -*u7MFq_
criteria.setProjection /=}w%-;/;
b*xw=G3%
(null); /}\EMP
List items = 0a??8?Q1G
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criteria.setFirstResult(startIndex).setMaxResults E1'HdOh&z
Eh)PZvH
(pageSize).list(); |Psi?'4
PaginationSupport ps = h7|#7 d
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new PaginationSupport(items, totalCount, pageSize, O$
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startIndex); 9""e*-;Mi
return ps; ? -PRS.=%
} W0&NX`m
}, true); ^b]h4z$
} C$~2FTx
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public List findAllByCriteria(final Uv~r]P)
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DetachedCriteria detachedCriteria){ fG107{!g=
return(List) getHibernateTemplate db%o3>>e
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().execute(new HibernateCallback(){ ;x*_h
publicObject doInHibernate ~5[#c27E9
|#);^z_
(Session session)throws HibernateException { +pcpb)VL
Criteria criteria = RjY(MSc
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detachedCriteria.getExecutableCriteria(session); VFj}{Y
return criteria.list(); VL5GX(
} o.ntzN
}, true); P".CZyI-i
} `<1o}r 7i
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public int getCountByCriteria(final }j^asuf~c
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DetachedCriteria detachedCriteria){ '`#sOH
Integer count = (Integer) x78`dX
*UVo>;
getHibernateTemplate().execute(new HibernateCallback(){ [=[>1<L>
publicObject doInHibernate 59;p|
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(Session session)throws HibernateException { X!,2/WT
Criteria criteria = roDE?7x1
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detachedCriteria.getExecutableCriteria(session); M<R3JzT
return _yi`relcq-
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criteria.setProjection(Projections.rowCount 4NaL#3
7JvBzD42
()).uniqueResult(); tA2Py
} fk5xIW
}, true); 1 PL2[_2:
return count.intValue(); w\o?p.drp=
} )YE3n-~7{
} P;7JK=~k
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v]UT1d=_T
用户在web层构造查询条件detachedCriteria,和可选的 |sP;`h}I%
\$.8iTr@
startIndex,调用业务bean的相应findByCriteria方法,返回一个 V2As 5
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PaginationSupport的实例ps。 TPjElBh
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ps.getItems()得到已分页好的结果集 AgEX,SPP
ps.getIndexes()得到分页索引的数组 5L6_W-n{
ps.getTotalCount()得到总结果数 PE $sF]/
ps.getStartIndex()当前分页索引 i2]7Bf)oV
ps.getNextIndex()下一页索引 5G$N
ps.getPreviousIndex()上一页索引 (X=JT
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w; [ndZCY7
zSy^vM;6zf
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 V
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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 _{Q)5ooP
,%)O/{p_
一下代码重构了。 "Y%fk/v8
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我把原本我的做法也提供出来供大家讨论吧: *0vq+C
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首先,为了实现分页查询,我封装了一个Page类: t zn1|
java代码: b#~K>
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/*Created on 2005-4-14*/ kq| r6uE
package org.flyware.util.page; +2:\oy}!8
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/** p.wed%O.
* @author Joa bwrM%BL
* b+=@;0p*6B
*/ !wbO:py[8>
publicclass Page { O*Gg57a
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/** imply if the page has previous page */ @:,B /B;
privateboolean hasPrePage; E?v9c>c
,>
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/** imply if the page has next page */ zR@4Z>6
privateboolean hasNextPage; azhilUD8
v11Uw?CM
/** the number of every page */ !uZ)0R
privateint everyPage; %C[#:>'+
RSfB9)3D
/** the total page number */ + d?p? v
privateint totalPage; DT;n)7+,
;H' ,PjU
/** the number of current page */ _*l+ze[a
privateint currentPage; >Hr&F
nh+
~ 3!yd0[k
/** the begin index of the records by the current @\*`rl]
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query */ WswM5RN
privateint beginIndex; _cc37[
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/** The default constructor */ ;*c8,I;
public Page(){ "?*B2*|}`
,=a+;D]'
} wZUZ"Y}9
$.Ia;YBf
/** construct the page by everyPage eoj(zY3
* @param everyPage
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* */ ,kQCCn]
public Page(int everyPage){ I]@QhCm0
this.everyPage = everyPage; q!10G
} Yt!o
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/** The whole constructor */ QBYY1)6S,
public Page(boolean hasPrePage, boolean hasNextPage, 1La?x'{2MP
xcQD]"
*Uw"`l
int everyPage, int totalPage, gB<1;_KW
int currentPage, int beginIndex){ 9^?2{aP%
this.hasPrePage = hasPrePage; SuR+Vv
this.hasNextPage = hasNextPage; d53Eu`QW?
this.everyPage = everyPage; w#d7
this.totalPage = totalPage; !U7}?i&H
this.currentPage = currentPage; mI,a2wqi
this.beginIndex = beginIndex; rff_=(?i
} :Z[|B(U
h
wi!C}
/** Gh5 3Pne
* @return 1Y:JGon
* Returns the beginIndex. ?vBMx _0
*/ r9Vt}]$aG
publicint getBeginIndex(){ [-0=ZKH?
return beginIndex; RRb>]oD
} H73 r3BH
Pk3b#$+E
/** ^/ff)'.J
* @param beginIndex :@b=;
* The beginIndex to set. Dnl|B\
*/ }~v&
publicvoid setBeginIndex(int beginIndex){ a9uMgx}
this.beginIndex = beginIndex; rDWwu'
} /EW=OZ/
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/** 84_Y+_9
* @return *kt|CXxAS8
* Returns the currentPage. wii.0~p
*/ yJ:rry
publicint getCurrentPage(){ FJp<J
return currentPage; 7\AoMk}
} a"{b}UP
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/** j;<s!A#
* @param currentPage ]pWn%aGv*Y
* The currentPage to set. vX?C9Fr2
*/ d"=)=hm!
publicvoid setCurrentPage(int currentPage){ )GfL?'Z
this.currentPage = currentPage; sB*!Nf^y
} v'Pbx
Nh01NY;
/** rA|&G'
* @return '};mBW4z
* Returns the everyPage. \Ez&?yb/
*/ '=+gweM
publicint getEveryPage(){ M4n0GWHLy
return everyPage; gg.lajX
} U]&/F{3
im
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/** kpRk.Q*
* @param everyPage )43z(:<
* The everyPage to set. 3F8KF`*
*/ J^=Xy(3e
publicvoid setEveryPage(int everyPage){ -;O"Y?ME
this.everyPage = everyPage; ><C9PS@
} ;>%wf3e
gSHN,8.
`
/** ,:{+-v(
* @return mLV0J '
* Returns the hasNextPage. (~NR."s;
*/ OD~yIV
publicboolean getHasNextPage(){ dn&484
return hasNextPage; oT!i}TW?o
} 3fUiYI|&7
~Zw37C9J
/** !iL6/
* @param hasNextPage y[/:?O}g4
* The hasNextPage to set. <OrQbrWQa
*/ h%5keiA
publicvoid setHasNextPage(boolean hasNextPage){ 5S ) N&%
this.hasNextPage = hasNextPage; zCS&w
~
} F9>"1
4,&f#=Y
/** 1*f/Y9 Z
* @return ?jsgBol
* Returns the hasPrePage. JF'<""
*/ /vPr^Wv
publicboolean getHasPrePage(){ ^SbxClUfw!
return hasPrePage; s)+] pxV0-
} e35")z~
^}UFtL i
/** j>5X^Jd
* @param hasPrePage dpT?*qLM
* The hasPrePage to set. LlD=c
*/ w3;T]R*
publicvoid setHasPrePage(boolean hasPrePage){ |+Xh ^E
this.hasPrePage = hasPrePage; hbSKlb0d
} 94?/Rhs5
h(i_'P?
/** 8g?2( MT;
* @return Returns the totalPage. Y}h&dAr
* x=N0H
*/ +.v+Opp,
publicint getTotalPage(){ d>0 j!+s
return totalPage; HP=5a.
} O4!!*0(+91
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/**
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* @param totalPage Z ?ATWCa
* The totalPage to set. `69xR[f
*/ u~!Pzz3"
publicvoid setTotalPage(int totalPage){ \Hu?K\SWs
this.totalPage = totalPage; H{uR+&<
} ,nWZJ&B
of'H]IZ
} U%KgLg#
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;+n25_9
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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 KcM+8W\
T^gi^{
个PageUtil,负责对Page对象进行构造: o}Zl/&(
java代码: u"(2Xer
p+;x&h)[l
b(A;mt#N
/*Created on 2005-4-14*/ ^oEaE#I
package org.flyware.util.page; ~g *`E!2
/+m7J"Km
import org.apache.commons.logging.Log; @9g!5dcT
import org.apache.commons.logging.LogFactory; ^t[br6G
2\#~%D>[
/** 5 HN,y
* @author Joa T'7x,8&2|
* zeuSk|O
*/ (Li)@Cn%
publicclass PageUtil { UO'X"`
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privatestaticfinal Log logger = LogFactory.getLog !^3j9<|@'
Y|<1|wGG
(PageUtil.class); ~{D:vj4>
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/** F5<GGEQb
* Use the origin page to create a new page _p| KaT``
* @param page '~76Y9mv
* @param totalRecords TzrU |D?
* @return yjucR
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*/ ^Y^5 @x=
publicstatic Page createPage(Page page, int NmV][0(BS
9|hPl-.
.W
totalRecords){ F:-6Htmj
return createPage(page.getEveryPage(), ;W!hl<``d*
!Op18hP$
page.getCurrentPage(), totalRecords); Q?Uk%t\hwc
} #~[mn_C
<PQ[N[SU
/** \JGRd8S[
* the basic page utils not including exception p+R8Mo;I
<$`udP@
handler pl.=u0 *
* @param everyPage <~Tfi*^+
* @param currentPage 7@i2Mz/eV
* @param totalRecords [oS.B\Vc
* @return page }u~r.=
*/ y{\(|j
publicstatic Page createPage(int everyPage, int }{e7wqS$&,
G$
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currentPage, int totalRecords){ ]TKM.[[
everyPage = getEveryPage(everyPage); kN$L8U8f
currentPage = getCurrentPage(currentPage); ,lw<dB@7"5
int beginIndex = getBeginIndex(everyPage, &?7+8n&+
:=%`\\
currentPage); B9h>
int totalPage = getTotalPage(everyPage, S?m4
.:jfNp~jt
totalRecords); [u`9R<>c"U
boolean hasNextPage = hasNextPage(currentPage, FZtILlw
cH$Sk
totalPage); D\V
(r\i
boolean hasPrePage = hasPrePage(currentPage); N%`Eq@5
"a>a
"Ei
returnnew Page(hasPrePage, hasNextPage, 6b#J!:?
everyPage, totalPage, 610hw376B
currentPage, oNBYJ]t
Gex%~';+q
beginIndex); (
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} ]6EXaf#
4kQL\Ld#E%
privatestaticint getEveryPage(int everyPage){ dDla?)F
return everyPage == 0 ? 10 : everyPage; w~=@+U$f
} t2vo;,^euL
Ic&Jhw;]z
privatestaticint getCurrentPage(int currentPage){ Oo95\Yf$N
return currentPage == 0 ? 1 : currentPage; Mkadl<
} &
pS5_x
REwZ41
privatestaticint getBeginIndex(int everyPage, int )*3sE1
VR_bX|
currentPage){ jR&AQ-H&
return(currentPage - 1) * everyPage; gL;tyf1P
} r`(U3EgP
YNi3oG]h
privatestaticint getTotalPage(int everyPage, int H">
}yD
kihO~<
totalRecords){ 5%6r,?/7KM
int totalPage = 0; =2[U4<d!R
e#$ZOK)`
if(totalRecords % everyPage == 0) L1E\^)
totalPage = totalRecords / everyPage; BpKgUwf;C
else APR%ZpG
totalPage = totalRecords / everyPage + 1 ; 6?c(ueiL[
I~>L4~g)
return totalPage; h47l;`kD-#
} #0j,1NpL
xN#. Pm~
privatestaticboolean hasPrePage(int currentPage){ B]YY[i
return currentPage == 1 ? false : true; $?u ^hMU=
} y(RK|r
Ka\%kB>*`
privatestaticboolean hasNextPage(int currentPage, SggS8$a`
fX2PteA0qX
int totalPage){ S?_ ;$Cn
return currentPage == totalPage || totalPage == 3QrYH
@7zx
Xpd^^
0 ? false : true; ii@O&g
} DOm5azO!>
TBYRY)~f
Pc4FEH/
} glppb$oB\
G&Sp }
RT)*H>|
'
cl&S:
5? s$(Lt~
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 V/G'{ q
nEM>*;iE
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 vWwnC)5
fH7o,U|
做法如下: uFT&r|
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 \i=,[8t[r
qe:,%a-9
的信息,和一个结果集List: Oj*3'?<7=
java代码: &` u<KKF6
ToN$x^M
w
dZ7+Iw;m
/*Created on 2005-6-13*/ pU*dE
package com.adt.bo; ,]'?Gd
ZAPT5
import java.util.List; Hs+VA$$*
"oYyeT
,?
import org.flyware.util.page.Page; YQ_3[[xT
M"]~}*
/** ^V~rS8]gj
* @author Joa ?1('s0s\,
*/ <Dw`Ur^X5
publicclass Result { V(Ps6jR"BS
\gL
H_$}
private Page page; 3~4e\xL
& ;+u.X
private List content; 5B?>.4R
wvm`JOP:A
/** |Y!#`
* The default constructor "S43:VH
*/ KFd"JtPg
public Result(){ h&Ehp
super(); Eq9TJt'3y
}
5eO`u8M
bO:Ei
/** 78\:{i->ta
* The constructor using fields (@dh"=Lt\
* Qcz7IA
* @param page Poacd;*
* @param content rs3Uk.Z^'
*/ lu(<(t,Lbs
public Result(Page page, List content){ 92GO.xAD?
this.page = page; z.:{
this.content = content; JI}(R4uV
} Wr7^
$LZf&q:\]*
/** A:EF#2)g
* @return Returns the content. DA@YjebP'
*/ s,Cm}4L6
publicList getContent(){ 8| zR8L
return content; ZN|DR|cUY
} qbkvwL9
@M?N[LG
/** A:1O:LB=!
* @return Returns the page. A?3hNvfx
*/ lkV%
k1w
public Page getPage(){ y5.Z<Y
return page; )kl| 5i
} >UpTMEQ
'N],d&fu^^
/** 8h~v%aZ1
* @param content k`r}Gb
* The content to set. :*e0Z2=
*/ 8f% @
public void setContent(List content){ k'wF+>
this.content = content; LQ?J
r>4
} 3KfZI&g
-,et. *
/** )]!Ps` ,u
* @param page rB}UFS)
* The page to set. [syuoJ
*/ BUv;BzyV
publicvoid setPage(Page page){ ~-Rr[O=E
this.page = page; V#|#%
8
} jcN84AaRFI
} MwL'
H<
`pN"T?Pk
mUzNrkG(G
7[QU
*1bk
l2=.;7IV
2. 编写业务逻辑接口,并实现它(UserManager, &TSt/b/+W
*8U+2zgfC
UserManagerImpl) =R!=uml(
java代码: +M
(\R?@gr
Fm{Ri=X<:
WKqNJN C
/*Created on 2005-7-15*/ cg<10KT
package com.adt.service; o)cd!,h
ji`N1e,l
import net.sf.hibernate.HibernateException; g||{Qmr=1
SMk{159q&
import org.flyware.util.page.Page; ?b:J6(-
/9|1eSUa
import com.adt.bo.Result; )dG7$,g
X^?<, Y)1.
/** )m"NO/sJ2
* @author Joa (zBa2Vmmv
*/ $.cNY+ k
publicinterface UserManager { [Ym?"YwVX
42:\1B#[
public Result listUser(Page page)throws ?
8S0
B>t$Z5Q^X
HibernateException; 18Vtk"j
>c\'4M8Cz
} i=reJ(y-
vAq`*]W+
$uawQf+S
8N!E`{W
w]UYD;f
java代码: 3ZU`}
\S}&QV
c&3
]%urL
/*Created on 2005-7-15*/ P`5@$1CJ
package com.adt.service.impl; \)DP(wC
f$iv+7<B^
import java.util.List; P
5m{}@g
A"\kdxC
import net.sf.hibernate.HibernateException; 4t|g G`QW7
j.sxyW?3
import org.flyware.util.page.Page; $/5Jc[Ow
import org.flyware.util.page.PageUtil; yVUA7IY
`z-4OJ8~
import com.adt.bo.Result; ]/HSlT=
import com.adt.dao.UserDAO; fg%I?ou
import com.adt.exception.ObjectNotFoundException; "QA#
import com.adt.service.UserManager; lOPCM1Se
@ ILG3"
/** WHqp7NPl
* @author Joa s,"<+80%
*/ Bra>C
publicclass UserManagerImpl implements UserManager { <G{m=
@xmO\
private UserDAO userDAO; ['sj'3cW-
qWHH%
L;
/** za1MSR
* @param userDAO The userDAO to set. *|Q'?ty(x
*/ e4ydn
publicvoid setUserDAO(UserDAO userDAO){
.rD@Q{e50
this.userDAO = userDAO; jB:$+k|~.
} >,y291p2
W@`Nn*S
/* (non-Javadoc) 3)T'&HKQ
* @see com.adt.service.UserManager#listUser *O#%hTYq
5.]+K<:h"A
(org.flyware.util.page.Page) E08FUAth]#
*/ Ps+0qqT*
public Result listUser(Page page)throws =;7gxV3;
x:88E78
HibernateException, ObjectNotFoundException { _:Tjq)
int totalRecords = userDAO.getUserCount(); Q$Ga.fI
if(totalRecords == 0) Ha@'%<gFe
throw new ObjectNotFoundException tU>wRw=d
nk>
("userNotExist"); F.HD;C-;(
page = PageUtil.createPage(page, totalRecords); v98=#k!F
List users = userDAO.getUserByPage(page); =GL}\I
returnnew Result(page, users); cZk?o
} 8E&}+DR?
o=_:g >5
}
T,@.RF
68Vn]mr#
6B)(kPW
~.u}v~
F
T(MS,AyD]
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Sav]Kxq{
M")JbuI
询,接下来编写UserDAO的代码: P(_D%0xKm
3. UserDAO 和 UserDAOImpl: &dh%sFy
java代码: n`2d
81eDN6
M\
3xxQL,FV
/*Created on 2005-7-15*/ yMq&9R9F
package com.adt.dao; UQ:H3
;o8C(5xE|
import java.util.List; ,=O`'l>K
AV Gu*
import org.flyware.util.page.Page; h$)(-_c3
ah1d0eP
import net.sf.hibernate.HibernateException; G+stt(k:
mp!KPw08':
/** @*]l.F
* @author Joa ^ llZf$`
*/ {E-.W"t4
publicinterface UserDAO extends BaseDAO { "XT7;!
]|it&4l
publicList getUserByName(String name)throws V%8?f,
+D[|L1{xb
HibernateException; '$YB
-
KtchKpv
publicint getUserCount()throws HibernateException; =dx!R ,Bw
gELku .
publicList getUserByPage(Page page)throws N:GSfM@g
BAG)
-
HibernateException; XE*
@*
7Ab&C&3
} 4sasf94
k__iJsk
XAwo~E
oGM Ls
A-^[4&rb
java代码: Q1jU{
Ig}G"GR
$h`(toTyF
/*Created on 2005-7-15*/ !O6e,l
package com.adt.dao.impl; '9c`[^
GL[#XB>n
import java.util.List; 4z#{nZG
3sIW4Cs7)U
import org.flyware.util.page.Page; MGze
IrV
usH9dys,
import net.sf.hibernate.HibernateException; Tm(XM<
import net.sf.hibernate.Query; #no~g(!o
Zt4g G KG
import com.adt.dao.UserDAO; 3I&=1o
?%%
'GX
/** njeRzX
* @author Joa Se<]g$eK?5
*/ jWJq[l
public class UserDAOImpl extends BaseDAOHibernateImpl 0<_|K>5dS|
$3<,"&;Ecs
implements UserDAO { +KgoLa
SF$7WG3Q
/* (non-Javadoc) XK??5'&{
* @see com.adt.dao.UserDAO#getUserByName IROX]f}r(
Rt:k4Q
(java.lang.String) Yv k
Qh{
*/ Z:DEET!c'k
publicList getUserByName(String name)throws I$/*Pt];
^]l^q'?>:
HibernateException { 9pUvw_9MY
String querySentence = "FROM user in class fZ1v|
QA>(}u\+
com.adt.po.User WHERE user.name=:name"; =y-L'z&r
Query query = getSession().createQuery 59mNb:<
<6QG7i
(querySentence); J!5BH2bg
query.setParameter("name", name); U/F<r3.`#
return query.list(); _OV\W'RrA
} w}No ^.I*4
u$ C@0d
/* (non-Javadoc) FdEzt
* @see com.adt.dao.UserDAO#getUserCount() Atsi}zTR\
*/ jXA!9_L7
publicint getUserCount()throws HibernateException { W9n0Jv
int count = 0;
N1,=5P$
String querySentence = "SELECT count(*) FROM #=F"PhiX`
uT'_}cw
user in class com.adt.po.User"; rE0?R(_
Query query = getSession().createQuery pm$2*!1F(
L08>9tf`
(querySentence); Y$xO&\&)
count = ((Integer)query.iterate().next \$:KfN>WY
Fx,08
()).intValue(); ^?PU:eS
return count; <i{O\K]9
} N<lejZ}!q
w1HE^
/
/* (non-Javadoc) =OfU#i"c
* @see com.adt.dao.UserDAO#getUserByPage -YM#.lQ
)Y%>t
(org.flyware.util.page.Page) n,sf$9"
*/ "hwg";Z$n
publicList getUserByPage(Page page)throws f!6oW(r-L
.K`OEdr<
HibernateException { wKF #8Y
String querySentence = "FROM user in class -
s[=$pDU
piYv}4;:(
com.adt.po.User"; OQzJRu)mF#
Query query = getSession().createQuery VD[x}8ei
jv$Y]nf
(querySentence); RtVy^~=G
query.setFirstResult(page.getBeginIndex()) r/v'h@
.setMaxResults(page.getEveryPage()); <;O=h;
~|
return query.list(); C
yg e
} #oRm-yDr
)E;+C2G
} zogtIn)
HScj
GMmz`O
XN
k.bzh.
E)==!T@E
至此,一个完整的分页程序完成。前台的只需要调用 n]M1'yU
\b{Aj,6,
userManager.listUser(page)即可得到一个Page对象和结果集对象 u I$|M
OLXkiesK{
的综合体,而传入的参数page对象则可以由前台传入,如果用 &qw7BuF
Bz}Dgbb
webwork,甚至可以直接在配置文件中指定。 fw>@:m_bK
!iKR~&UpAL
下面给出一个webwork调用示例: u] C/RDTH
java代码: TymE(,1
hUirvDvX
q6A!xQs<
/*Created on 2005-6-17*/ zJ{?'kp
package com.adt.action.user; 6o@}k9AN
89@\AjI
import java.util.List; 8N<0|u
W{E22J}
import org.apache.commons.logging.Log; o(xRq;i
import org.apache.commons.logging.LogFactory; #_yQv?J
import org.flyware.util.page.Page; rfqw/o
xdWfrm$;ZA
import com.adt.bo.Result; (Wkli:Lq
import com.adt.service.UserService; Zgp]s+%E
import com.opensymphony.xwork.Action; [6x-c;H_4
0_yE74i
/** F#=XJYG1
* @author Joa t~pA2?9@
*/ #PnuR2s7.
publicclass ListUser implementsAction{ !_GY\@}
B5J!&suX
privatestaticfinal Log logger = LogFactory.getLog ~~:w^(s9
j,Sg?&"%=
(ListUser.class); }Ictnb
"=4`RM
private UserService userService; {Z[yY6Nu
c>fLSf
private Page page; xsK{nM6g
%bf+Y7m
privateList users; $q*kD#;mh
-1Y9-nn[m
/* PoMkFG6
* (non-Javadoc) ps0wN%tA
* SsA;T5:6
* @see com.opensymphony.xwork.Action#execute() $iQ>c6
*/ \~xI#S@
publicString execute()throwsException{ ?]gZg[
Result result = userService.listUser(page); @C)O[&Sk
page = result.getPage(); Dd|}LV
users = result.getContent(); g-'y_'%0G
return SUCCESS; mhTpR0
} ZK5(_qW&i
7t-j2 n`<
/** CG'NC\x5
* @return Returns the page. R`=3lY;
*/ .4={K)kz|F
public Page getPage(){ *D`qcv
return page; BqZ^I eC$
} #QJ
mAA
}GvoQ#N
/** Mq) n=M
* @return Returns the users. :1u>T3L.z
*/ ga#,42)H
publicList getUsers(){ 5@c,iU-L
return users; zi:F/TlUC
} Z+ubc"MVb
Cus=UzL
/** ^|}C!t+
* @param page Ab7hW(/
* The page to set. /uI/8>p(
*/ EQPZV
K/
publicvoid setPage(Page page){ iU^ 4a
this.page = page; SCeZt [
} RAKQ+Y"nl
O%v(~&OSl
/** b3b 4'l
* @param users hTI8hh
* The users to set. j)\&#g0u6
*/
7'FDI`e[
publicvoid setUsers(List users){ mOwgk7s[J
this.users = users; >7!aZO
} Pb?H cg
Ku LZg
/** wo2^,Y2z+
* @param userService R#~}ZUk2
* The userService to set. G B!3`
A%&
*/ qx
3.oU
publicvoid setUserService(UserService userService){ jIE>t5 fy
this.userService = userService; kFv\V
} )DMu`cD
} )ufHk
~l!(I-'?g
$m/-E#I#Z
U[d/`
X@+:O-$
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, &n<jpMB
a#H=dIj
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 Ary$,3X2
R+]p
-NI^
么只需要: %9M; MK
java代码: D{o1G?A
$o\p["DP
cNC\w%
<?xml version="1.0"?> .Q"3[
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork f[7'kv5S
t^?8Di\
1.0//EN" "http://www.opensymphony.com/xwork/xwork- M)Rp+uQ
cYx=8~-
1.0.dtd"> ;0E"4(S.q1
g|<)J-`Q
<xwork> CkoPno
q<>2}[W
<package name="user" extends="webwork- UEo,:zeN[
d1e'!y}R5
interceptors"> &o"Hb=k<
4:r^6m%%
<!-- The default interceptor stack name QXJD'c
ZC"6B(d
--> 1ISA^< M
<default-interceptor-ref e"r'z
n
UQ|0Aqwq
name="myDefaultWebStack"/> };9dd3X
%W"\
<action name="listUser" '5ky<
(/YC\x?
class="com.adt.action.user.ListUser"> mk\U wv
<param 1@)]+* F*z
gbpm::
name="page.everyPage">10</param> @PwEom`a
<result ?]fBds=
$O}gl Q
name="success">/user/user_list.jsp</result> 1\YX|
</action> ^'EEry
:^%soEi
</package> EfDo%H^!j
:#TJ-l:#
</xwork> ,_NO[+5U
9Z*`{
R5]R
pW=G
%h|z)
jLr8?Hyf
4L!{U@'
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 IUd>jHp`6
A!^K:S:@
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 /bCrpcH
YD@V2gK
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 tB(Q-c
hph 3kfR
Jq6p5jr"
O.rk!&N
v@>hjie
我写的一个用于分页的类,用了泛型了,hoho P]Gsc
QQ2xNNF[
java代码: ^|\ *i
KD,b.s
}QJE9;<e
package com.intokr.util; Slv}6at5
d1y(Jt
import java.util.List; 8.k"kXU@n
}$qy_Esl
/** "Wi`S;
* 用于分页的类<br> BOwkC;Q[
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ~Ag!wj
* ,}{E+e5jh7
* @version 0.01 =Rb,`%
* @author cheng -^#Ix;%
*/ 44%::Oh
public class Paginator<E> { >5^Z'!Z"
privateint count = 0; // 总记录数 `dL9sfj>
privateint p = 1; // 页编号 ][G<CO`k
privateint num = 20; // 每页的记录数 _"WQi}Mm
privateList<E> results = null; // 结果 Nq*\{rb
0w+hf3K+:
/** W!tP sPM
* 结果总数 I5x/N.
*/ vpXS!o>/Sn
publicint getCount(){ P45q}v
return count; 8 6L&u:o:
} h)y"?Jj
|AFF*]e S
publicvoid setCount(int count){ )3)L
this.count = count; <[~x]-
} =,T~F3pK
#v&&GuF
/** #G*z{BRQ
* 本结果所在的页码,从1开始 #mllVQ
* vjXvjv{t
* @return Returns the pageNo. ; $y.+5 q
*/ Ro-Mex2
publicint getP(){ H[>_LYZ8
return p; }Bc6:a
} 1]hMA\x
)3..7ht3^5
/** /AMtT%91
* if(p<=0) p=1 5lU`o
* %{HqF>=~
* @param p tY[y?DJ
*/ 8|d[45*q
publicvoid setP(int p){ 4yBe(&N-d
if(p <= 0) #e9B|Y?b
p = 1; mDM]RAub)
this.p = p; '|]zBpz
} |fw+{f
{qx"/;3V
/** QGLm4 Wl9
* 每页记录数量 C62<pLJf
*/
Kjf#uU.7
publicint getNum(){ "\>3mVOb
return num; }(hE{((o
} MnX2sX|
2}}~\C}o+
/** s#d# *pgzh
* if(num<1) num=1 5X`.2q=d
*/ n:#ji|wM
publicvoid setNum(int num){ Xp{gh@#dr
if(num < 1) QPFpGS{d
num = 1; !4 hs9b
this.num = num; mB1)!
} rBny*!n
P{}Oe
*9"
/** 5:s]z#8)
* 获得总页数 nEGku]pCH{
*/
_8S).*
publicint getPageNum(){ J@Orrz2q#
return(count - 1) / num + 1; %
tJ?dlD'
} |/<iydP
m.^6ef
/** aoJ&< vl3
* 获得本页的开始编号,为 (p-1)*num+1 &pmJ:WO,h
*/ hqBwA1](a
publicint getStart(){ mYy3KqYu
return(p - 1) * num + 1; d->b9
} x`lBG%Y[-v
gq0gr?
/** pixI&iQ
* @return Returns the results. f
a\cLC
*/ fe0 Y^vW
publicList<E> getResults(){ d@w
I:
7
return results; Yb6\+}th
} tjTF?>^6|
[2FXs52
public void setResults(List<E> results){ N\Hd3Om
this.results = results; 8bK}&*z<
} 'PO1{&M
4o=G) KO{
public String toString(){
A{c6XQR~z
StringBuilder buff = new StringBuilder |j!D _j#U
XG[%oL
(); -#i%4[v
buff.append("{"); Z7f~|}
buff.append("count:").append(count);
"Km`B1f`
buff.append(",p:").append(p); K3Xy%pqR#
buff.append(",nump:").append(num); a%]p*X!
buff.append(",results:").append 2xnOWW
un/eS-IIh
(results); brVT
buff.append("}"); P;y/`_jo
return buff.toString(); 0SDCo\
} AVJF[t,
#/ 4Wcz<
} utTek5/
x[?_F
wXZ-%,R-D