Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Ww[Xqmg
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 (1pR=
m'b9 f6
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 MN.h,^b
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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 2.>WR~\
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分页支持类: @|jLw($Ly
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java代码: |g@n'^]
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package com.javaeye.common.util; e@ mjh,
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import java.util.List; X^td`}F/=V
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publicclass PaginationSupport { =,])xzG%
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publicfinalstaticint PAGESIZE = 30; KqD]GS#(
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privateint pageSize = PAGESIZE; g"dq;H
hp$/O4fD
privateList items; %wDE+&M
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privateint totalCount; <?&Y_
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privateint[] indexes = newint[0]; 2lc
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privateint startIndex = 0; ZR,"w
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public PaginationSupport(List items, int (qbL=R"
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totalCount){ T@ 4R|P&{)
setPageSize(PAGESIZE); _&wrA3@/L
setTotalCount(totalCount); VK]cZ%)
setItems(items); 5{"v/nXV
setStartIndex(0); l+vD`aJ 3
} wqnHaWd*
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public PaginationSupport(List items, int ^vHh*Ub
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totalCount, int startIndex){ i!a.6Gq
setPageSize(PAGESIZE); )/y7Fh
setTotalCount(totalCount); 3 i;sB
setItems(items); y v58~w*"
setStartIndex(startIndex); mM $|cge"
} ^ 5D%)@~
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public PaginationSupport(List items, int -`8pahI
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totalCount, int pageSize, int startIndex){ 7G\a5
setPageSize(pageSize); B@ xjwBUk
setTotalCount(totalCount); $SOFq+-T
setItems(items); L7`=ec<
setStartIndex(startIndex);
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} N8E
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publicList getItems(){ 3-PqUJT$
return items; CiNOGSlDj
} 2bnYYQ14:
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publicvoid setItems(List items){ (B^rW,V[R
this.items = items; M/mm2?4
} 7@1GSO: Yf
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publicint getPageSize(){ B" 0a5-pkr
return pageSize; N*`qsv0
} H,3WdSL`K
K0usBA
publicvoid setPageSize(int pageSize){ _m.w5nJ
this.pageSize = pageSize; x>bGxDtu*
} {6tj$&\)
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publicint getTotalCount(){ }WV}in0
return totalCount; ^7SE2Zi
} T!ww3d
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publicvoid setTotalCount(int totalCount){ }|OwUdE!R9
if(totalCount > 0){ S0'
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this.totalCount = totalCount; S
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int count = totalCount / OfK>-8
idNra#
pageSize; Rz#q68
if(totalCount % pageSize > 0) k.ttrKy<q/
count++; Q@
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indexes = newint[count]; X5tx(}j
for(int i = 0; i < count; i++){ srQGqE~
indexes = pageSize * %xv*#.<Vj
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i; B2,c_[UZ.
} q|g>;_
}else{ 8CUlE-R5
this.totalCount = 0; 3oOr*N3R
} ]SmN}Iq1
} Miz?t*|{[
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publicint[] getIndexes(){ i*((@:
return indexes; #M)+sK$H%f
} ]5r@`%9
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publicvoid setIndexes(int[] indexes){ B#G:aBCM
this.indexes = indexes; mt]^d;E
} |[)n.N65=
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publicint getStartIndex(){ EeR} 34
return startIndex; =<%[P9y
} 4nrn
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publicvoid setStartIndex(int startIndex){ ?2%;VKN4
if(totalCount <= 0) U,K=(I7OBX
this.startIndex = 0; wJZuJ(
elseif(startIndex >= totalCount) O.DO,]Uh
this.startIndex = indexes 3yrb7Rn3
bd\%K`JQ{
[indexes.length - 1]; @'9m()%-]g
elseif(startIndex < 0) YsMM$rjP+
this.startIndex = 0; s o1hC
else{ hv`I`[/J
this.startIndex = indexes ^
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[startIndex / pageSize]; 6f:u AFwG
} '3b'moy
} X'88W-
DNr*|A2<
publicint getNextIndex(){ <aLS4
int nextIndex = getStartIndex() + unih"};ou
$^_6,uBM[
pageSize; .e5d#gE0
if(nextIndex >= totalCount) IZLBv2m
return getStartIndex(); u].7+{
else 8iTB
return nextIndex; xnfJruT
} uBl&{$<
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publicint getPreviousIndex(){ \zcR75
int previousIndex = getStartIndex() - as(/
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pageSize; JW!.+
Q
if(previousIndex < 0) \(RD5@=!4#
return0; S1[, al
else = N;5T
return previousIndex; R nwFxFIQ
} &f}w&k2yj
n@L@pgo%~
} U\u07^h[
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抽象业务类 !6l*Jc3
java代码: (g*j+i
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/** \1SC:gN*#
* Created on 2005-7-12 i),bAU!+m
*/ ap8q`a{j^
package com.javaeye.common.business; 4l7
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import java.io.Serializable; wBvVY3VQ^
import java.util.List; =P%&]5ts
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import org.hibernate.Criteria; ;NH^+h
import org.hibernate.HibernateException; z)(W
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import org.hibernate.Session; Rx.v/H
import org.hibernate.criterion.DetachedCriteria; C5~n^I|
import org.hibernate.criterion.Projections; r6nnRN/S=
import :w-:B^VB
$}.+}'7$
org.springframework.orm.hibernate3.HibernateCallback; 1+gF fKq
import |;7mDhj=
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org.springframework.orm.hibernate3.support.HibernateDaoS ;*$e8y2
Jt[,V*:#
upport; LRg]'?
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import com.javaeye.common.util.PaginationSupport; B]H8^
@({=~
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public abstract class AbstractManager extends 7nPcm;Er
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HibernateDaoSupport { :EAh%q
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privateboolean cacheQueries = false; -pIz-*
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privateString queryCacheRegion; haY]gmC
%S"85#R5E
publicvoid setCacheQueries(boolean b*.aaOb
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cacheQueries){ vJaWHC$q
this.cacheQueries = cacheQueries; h=0a9vIXF
} i%JJ+9N
Ix6\5}.c 9
publicvoid setQueryCacheRegion(String "a=Hr4C*r
"p*'HQ
queryCacheRegion){ tfN[-3)Z
this.queryCacheRegion = @ ?M\[qeF@
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queryCacheRegion; i6KB\W2
} Q3(ulgl]
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publicvoid save(finalObject entity){ I8YUq
getHibernateTemplate().save(entity); &
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} *g,ls(r\[
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publicvoid persist(finalObject entity){ Z[OX{_2]K
getHibernateTemplate().save(entity); 9OV@z6
} YR*gOTD
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publicvoid update(finalObject entity){ L2,2Sn*4i
getHibernateTemplate().update(entity); Z3weFbCH
} gu!!}pwV9
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publicvoid delete(finalObject entity){ pa1<=w
getHibernateTemplate().delete(entity); 5E-;4o;RI(
} K^U="
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publicObject load(finalClass entity, ZX` \so,&,
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finalSerializable id){ 2t9UJu4
return getHibernateTemplate().load $Yt|XT+!&
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(entity, id); 7;o:r$08&}
} S)rr
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publicObject get(finalClass entity, \1jThJn
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finalSerializable id){ H oABo:
return getHibernateTemplate().get ?UAuUFueA
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(entity, id); {KNaJ/:>W
} Vf&U`K
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publicList findAll(finalClass entity){ 1oej<67PdJ
return getHibernateTemplate().find("from I09 W=
O{_t*sO9q*
" + entity.getName()); vt{[_L(h
} 8Y.qP"s
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publicList findByNamedQuery(finalString !:!(=(4$P
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namedQuery){ q* p
return getHibernateTemplate h(HpeN%`#
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().findByNamedQuery(namedQuery); oI{.{]
} a]u.Uqyx2w
7b[sW|{
publicList findByNamedQuery(finalString query, Tse#{
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finalObject parameter){ Q;$k?G=l
return getHibernateTemplate Eo6N'h >h
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().findByNamedQuery(query, parameter); =O }^2OARo
} ~i"=:D
*'-4%7C`1
publicList findByNamedQuery(finalString query, Gk*u^J(
(<eLj Q
finalObject[] parameters){ X\h.@+f=
return getHibernateTemplate fWmc$r5n](
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().findByNamedQuery(query, parameters); 'z.
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} X[o+Y@bc
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9
publicList find(finalString query){ ;#85 _/
return getHibernateTemplate().find ojy^A
<?KPyg2
(query); )XDBK*!
} /aI@2] |~
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publicList find(finalString query, finalObject +>#SNZ[
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parameter){ PY5 &Fwjc
return getHibernateTemplate().find uCDe>Q4@/
jsN[Drr a
(query, parameter); T)\}V#iA*
} N:<$]x>
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public PaginationSupport findPageByCriteria 3J#LxYK
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(final DetachedCriteria detachedCriteria){ KV_/fa~Ry
return findPageByCriteria G?$@6
Ab@G^SLX
(detachedCriteria, PaginationSupport.PAGESIZE, 0); irAXXg
} 0F |t@?S
Kyh>O)"G^%
public PaginationSupport findPageByCriteria =\O#F88ui
GOc
(final DetachedCriteria detachedCriteria, finalint MT-Tt
Zk=,`sBC
startIndex){ iwK.*07+
return findPageByCriteria <gF]9%2E
k_7m[o
(detachedCriteria, PaginationSupport.PAGESIZE, ;7P'>j1?U
)dkU4]
startIndex); VmqJMU>.
} qdix@@
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public PaginationSupport findPageByCriteria uyWheR
[7vV#s3kJ
(final DetachedCriteria detachedCriteria, finalint Uj(0M;#%o+
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pageSize, PQ4mNjXN
finalint startIndex){ RsZj
return(PaginationSupport) sUG!dwqqd
3(WijtH
getHibernateTemplate().execute(new HibernateCallback(){ +HS]kF H
publicObject doInHibernate eN=jWUoCh
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(Session session)throws HibernateException { i1B!oZ3q
Criteria criteria = $,}jz.R@
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detachedCriteria.getExecutableCriteria(session); QOB^U-cW
int totalCount = NIs 7v
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((Integer) criteria.setProjection(Projections.rowCount
]=~dyi
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()).uniqueResult()).intValue(); [J,.?'V
criteria.setProjection VfcIR(
*BsK6iVb
(null); )pHtsd. eP
List items = sM-,95H
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criteria.setFirstResult(startIndex).setMaxResults cXb*d|-|N
wEjinP$2
(pageSize).list(); Y}ogwg&
PaginationSupport ps = jri"# H
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new PaginationSupport(items, totalCount, pageSize, a:cci?cb
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startIndex); O <Rh[Aqn
return ps; `==l2AX
} XO
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}, true); h5P_kZJ
} ;XN|dq
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public List findAllByCriteria(final P6v ANL-B
{ M**a
DetachedCriteria detachedCriteria){ 4m0^
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return(List) getHibernateTemplate +hN>Q$E
zy,SL
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().execute(new HibernateCallback(){ fmW{c mr|
publicObject doInHibernate RDdnOzx
Ev7.!
(Session session)throws HibernateException { al2lC#Sy
Criteria criteria = xgk~%X%K
kq}byv}3I
detachedCriteria.getExecutableCriteria(session); 2z-Nw <bA
return criteria.list(); w/6X9d
} {'IO
}, true); 11oNlgY&
} kOydh(yE
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public int getCountByCriteria(final vJ&_-CX
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DetachedCriteria detachedCriteria){ PeJ#9hI~rQ
Integer count = (Integer) njs:
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getHibernateTemplate().execute(new HibernateCallback(){ ]hS:0QE
publicObject doInHibernate m4/qxm"Dx:
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q
(Session session)throws HibernateException { ~F,~^r!Jtu
Criteria criteria = aKj|gwo!
u9"=t
detachedCriteria.getExecutableCriteria(session); 7P<VtS
return s47R,K$
jqaX|)8|$
criteria.setProjection(Projections.rowCount 'zYS:W
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()).uniqueResult(); wMVUTm
} 91]|4k93
}, true); WoTeIkM9
return count.intValue(); gv`_+E{P
} 9S%5Z>
} So1TH%
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用户在web层构造查询条件detachedCriteria,和可选的 t.(
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 E;a,].
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PaginationSupport的实例ps。 z x-[@G
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ps.getItems()得到已分页好的结果集 30sJ"hF9
ps.getIndexes()得到分页索引的数组 QD@O!};
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ps.getTotalCount()得到总结果数 ?\Z pVL<>
ps.getStartIndex()当前分页索引 w
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ps.getNextIndex()下一页索引 M@.l#
[@U
ps.getPreviousIndex()上一页索引 Q5ASN"_
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 j=O+U_w
T1d@=&0"
,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 vFk@
)k(K/m
一下代码重构了。 }k }=e
nYx
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我把原本我的做法也提供出来供大家讨论吧: @\g}I`_M
FsED9+/m
首先,为了实现分页查询,我封装了一个Page类: !/p|~K
java代码: )J 'F]s
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/*Created on 2005-4-14*/ IH`Q=Pj
package org.flyware.util.page; (,I:m[0
21v--wZ
/** 4!/QB6
* @author Joa ?,$:~O*w
* d~<$J9%
*/ ;KQU%
k$
publicclass Page { ":/c|!
C98F?uo%Q
/** imply if the page has previous page */ ?g ,s<{
privateboolean hasPrePage; !gkr?yhE
T~xVHk1
/** imply if the page has next page */ (u 7Lh>6%
privateboolean hasNextPage; 6y^
zC?
\Eh5g/,[
/** the number of every page */ Zv
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privateint everyPage; ~<_#%R!
S>dHBR#AD
/** the total page number */ V48_aL
privateint totalPage; ?$/::uo
qArR5OJ
/** the number of current page */ ?2"g*Bak
privateint currentPage; 8xlj,}QO\
p6j-8ggL
/** the begin index of the records by the current ;T^s&/>E
={BC0,
query */ uj3`M9
privateint beginIndex; #2^0z`-\_z
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Qf_N,Bq{a
/** The default constructor */ X`g<"Ka
public Page(){ (1CP]5W
5~h)pt47
} kqeEm{I
c^w^'<
/** construct the page by everyPage E{V?[HcWq
* @param everyPage T9c7cp[
* */ U
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public Page(int everyPage){ &0T.o,&y
this.everyPage = everyPage; x@Gg fH<l
} M5VW1Ns
^KbR@Ah
/** The whole constructor */ Vs"b
public Page(boolean hasPrePage, boolean hasNextPage, P.YT/
5mAb9F8@
+k6`
tl~*
int everyPage, int totalPage, mPA)G,^
int currentPage, int beginIndex){ 9Buss+K?/h
this.hasPrePage = hasPrePage; ]2-Qj)mZ]
this.hasNextPage = hasNextPage; {mU%.5
this.everyPage = everyPage; @]Vcl"t
this.totalPage = totalPage; N #v[YO`.
this.currentPage = currentPage; HW[&q
this.beginIndex = beginIndex; '_?Z{|
} Kii@Z5R_?
+j: &_
/** X8tPn_`x
* @return h>V6}(~;.
* Returns the beginIndex. l=xG<)Okb
*/ c7+6[y DVE
publicint getBeginIndex(){ 7NJl+*u
return beginIndex; )y]Dmm
} _!2lnJ4+5
|4DN2P
/** N@PuC>
* @param beginIndex ;\th.!'rn
* The beginIndex to set. .J -k^+-
*/ 1V`-D8-?
publicvoid setBeginIndex(int beginIndex){ mZU
L}[xf
this.beginIndex = beginIndex; 5"h4XINZ
} 6KGT?d
-|'@:cIZ
/** -Jd7
* @return Z+V%~C1
* Returns the currentPage. PZ/tkw
*/ ~xG/ yPl
publicint getCurrentPage(){ V(cU/Aia^
return currentPage; l8E))oz1T
} t5 >ma:^j
Ju>QQOxi|
/** dkg`T#}
* @param currentPage `u3kP
* The currentPage to set. r~=+>,
_
*/ 4(,.<#
publicvoid setCurrentPage(int currentPage){ GQg
2!s(
this.currentPage = currentPage; 48,*sTRq
} 1[OY -G
MVMJl ">
/** kQU4s)J
* @return ~
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* Returns the everyPage. HCr}|DxyK
*/ Ip{hg,>
publicint getEveryPage(){ #N3*SE
return everyPage; hg12NzbK
} y:\<FLR}j
T}\>8EEG
/** !=30s;-
* @param everyPage ,w "cY?~<
* The everyPage to set. Sy?^+JdM/
*/ trwo(p
publicvoid setEveryPage(int everyPage){ $Ud9v 4
this.everyPage = everyPage; "u^2!d
} 8]&Fu3M^
>CG;df<~
/** >#dLT~[\a
* @return 3^Is4H_8
* Returns the hasNextPage. tY#&_%W
*/ u9:sj
publicboolean getHasNextPage(){ zk }SEt-
return hasNextPage; 5[\g87\
} bLl
?!G.
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/** 6&+dpr&c~=
* @param hasNextPage ^Zs^
* The hasNextPage to set. =l2 @'Y Q
*/ W\Il@Je;
publicvoid setHasNextPage(boolean hasNextPage){ 9Cd=^Im5
this.hasNextPage = hasNextPage; Qv,ORm
h5
} f`vWCb
vy
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/** c-zW
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* @return jB -Ad8
* Returns the hasPrePage. D7R;IA-w
*/ %A
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publicboolean getHasPrePage(){ L?N:4/0;!
return hasPrePage; *#p}FB2H#
} Z3zD4-p$_
LP7jCt
/** =WF@S1
* @param hasPrePage Fu?_<G%Ynp
* The hasPrePage to set. eOVln1a
*/ c&#Q`m
publicvoid setHasPrePage(boolean hasPrePage){ GwgY{-|`
this.hasPrePage = hasPrePage; pb<eg,
} Q_/UC#I8
`-s]dq
/** |@rf#,hTDp
* @return Returns the totalPage. XwIHIG}
* rU>l(O'b
*/ _ y'g11 \
publicint getTotalPage(){ ;|= 5)KE
return totalPage; O&CY9
2)Lk
} REc90v2"
Aa-OMo;~
/** Gf7r!Ur;g
* @param totalPage }K.)yv n
* The totalPage to set. P2>_qyX
*/ cgcU2N6y;
publicvoid setTotalPage(int totalPage){ 9R+ qw
this.totalPage = totalPage; varaBFD
} 1h]nE/T.O
).Z
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} f U<<GK70
`)=sQ2P
*ax&}AHK[/
}uD*\.
ZDK+>^A)
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 FKtCUq,:
CW@EQ3y0
个PageUtil,负责对Page对象进行构造: ;[C_ho
java代码: KVC18"|f
aB&a#^5CI
gW G>}M@
/*Created on 2005-4-14*/ \= 6dF,V
package org.flyware.util.page; x;JC{d#
6[Mu3.T
import org.apache.commons.logging.Log; Kr<a6BEv5
import org.apache.commons.logging.LogFactory; ;Uypv|xX
fsKZ
/** ^AwDZX
* @author Joa @ uL4'@Ej
* Rs]Y/9F;{
*/ 1b7 Q-elG
publicclass PageUtil { 06af{FXsGb
G`v(4`tA
privatestaticfinal Log logger = LogFactory.getLog F{&0(6^p!
x;&iLQZh
(PageUtil.class); ]o9^?iU]
Q:b>1
/** _P_R`A)"
* Use the origin page to create a new page Re;[S[D7
* @param page RLVz "=
* @param totalRecords {f6~Vwf
* @return gE&83i"
*/ 1A7(s0J8 :
publicstatic Page createPage(Page page, int !&G&
~*.x
"f!H[F1~
totalRecords){ zM%2h:*+{
return createPage(page.getEveryPage(), EzU=q
E
]D>\Z(b
page.getCurrentPage(), totalRecords); x50ZwV&j
} +o6"Z)
I&&[ ':
/** |3EKK:RE
* the basic page utils not including exception uw&p)
gr>>]C$
handler C%P"\>5@
* @param everyPage .L3D]
* @param currentPage v00w
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* @param totalRecords J.,7d ,
* @return page U)S!@2(4
*/ >
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publicstatic Page createPage(int everyPage, int a[BIY&/Q
QlnI &o
currentPage, int totalRecords){ $=!_ !tr
everyPage = getEveryPage(everyPage); >s%m\"|oh
currentPage = getCurrentPage(currentPage); /n9,XD&)
int beginIndex = getBeginIndex(everyPage, >@|XY<
sc# q03
currentPage); |/RZGC4
int totalPage = getTotalPage(everyPage, &~N@M!`Dn
kSqMI'89
totalRecords); `Yo!sgPO\
boolean hasNextPage = hasNextPage(currentPage, hRktvO)K
*edhJUT
totalPage); Z=144n 1
boolean hasPrePage = hasPrePage(currentPage); D0p>Q^w
u85Uy
yN
returnnew Page(hasPrePage, hasNextPage, &(X-b"2
everyPage, totalPage, 'CjcFP
currentPage, LeXkl=CC
Cbr>\;sc2Z
beginIndex); '_M"yg6d
} :&=`xAX-
\yo)oIi[p
privatestaticint getEveryPage(int everyPage){ >~* w
return everyPage == 0 ? 10 : everyPage; X=X
} dj:6c@n
5uvFCY./c
privatestaticint getCurrentPage(int currentPage){ II}3w#r4
return currentPage == 0 ? 1 : currentPage; ujoJ6UOG
} F@@6D0\X?
@O&; %IZMY
privatestaticint getBeginIndex(int everyPage, int G+W0X
"D/\&1.&
currentPage){ sxn^1|O;m
return(currentPage - 1) * everyPage; qa)Qf,`
} 9d >AnTf&H
%1PNP<3r0
privatestaticint getTotalPage(int everyPage, int :J;*]o:
{$qLMx';
totalRecords){ +m1y#|08
int totalPage = 0; v^Pjvv =
LLW\1 cxi
if(totalRecords % everyPage == 0) b#{[Pk,w9
totalPage = totalRecords / everyPage; \m3ca-Y
else jf~-;2
totalPage = totalRecords / everyPage + 1 ; ~g|z7o
]w9\q*S]
return totalPage; 8al%F_r]
} 0X4%Ccs
[<A|\d'x
privatestaticboolean hasPrePage(int currentPage){ 2VA mL7)
return currentPage == 1 ? false : true; Jhr3[A
} ^@n?&
o"e]9{+<
privatestaticboolean hasNextPage(int currentPage, x`gsD3C
4^AdSuV
int totalPage){ Qj',&b
return currentPage == totalPage || totalPage == .l ufE
e"ur+7
0 ? false : true; |qX[Dk
} )i*- j=
KMogwulG
?CUGJT
} Tn 3<cO7v
u|D|pRM-LT
;*409P
8k
-l`O~
^Jdji:
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。 6]5e(J{Fz
YO`V'6\
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 ?'r=>'6D
|$a!Zx94^
做法如下: HmZ*
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 QcG-/_,'}
}2~$"L,_
的信息,和一个结果集List: 7C@%1kL
java代码: "3X~BdH&J
KO5! (vi@
3zuYN-;
/*Created on 2005-6-13*/ jK9#.
0
package com.adt.bo; "YePd*W
^OnZ9?C{R
import java.util.List; byetbt(IF
Ym5ji$!2
import org.flyware.util.page.Page; cfA)Ui
0L|D1_k[
/** QFX )Nov];
* @author Joa E|l qlS7
*/ pLea 4
publicclass Result { Z@{e\sZ)
d\A!5/LG
private Page page; ),]XN#jp(u
g|rbkK%SoE
private List content; kKEs >a
KBkS>0;X
/** !,zRg5Wp4
* The default constructor TW5Pt{X=f
*/ N9=1<{Z
public Result(){ kcN#g-0
super(); v3/l=e?u
} TG@ W:>N(
2UJjYrm
/** )7}f.
* The constructor using fields Y$&+2w,)H,
* #Z>EX?VS:
* @param page vo JmNH
* @param content z}&JapJ
*/ g;G]Xi.B}
public Result(Page page, List content){ C3>`e3v
this.page = page; nb ,+!)+
this.content = content; %AnqT|\#,
} 1aBQ.-E-
}{(J*T
/** +JrbC/&
* @return Returns the content. (n0h#%
*/ mcqLN5
publicList getContent(){ r}Ec_0_lt
return content; @_4E^KgF
} N497"H</
I`
+%ab
/** qGrUS_~q*
* @return Returns the page. .T|1l$Jn
*/
i_M0P1 2
public Page getPage(){ ~rICPR
return page; [+4/M3J%
} $++SF)G1]_
0` \!O(jJ
/** dAkJ5\=*
* @param content 052ezh_
* The content to set. 7IUu] Fi
*/ Gbrc!3K2
public void setContent(List content){ IP=."w
this.content = content; FhVoN}
} lbUUf}
nOj0"c
/** # )]L3H<
* @param page YR/%0^M'0
* The page to set. 6h%_\I.Z[[
*/ /_.1f|{B
publicvoid setPage(Page page){ ?f'iS#XL
this.page = page; mX&!/U
} vS'l@`Eg]
} t`oH7)nut
q@0g KC&U
*j"u~ NF
`#x}-A$
5,Hj$v7fe
2. 编写业务逻辑接口,并实现它(UserManager, V4>qR{5
h}SP`
UserManagerImpl) 1Q>D^yPI[
java代码: >3&Oe
?@YABl
S?K x:]
/*Created on 2005-7-15*/ %.[jz,;)
package com.adt.service; 5eJMu=UpR
09L"~:rg
import net.sf.hibernate.HibernateException; Q$XNs%7w5,
(N
0kTi]b
import org.flyware.util.page.Page; gof'NT\c
%&Q9WMo
import com.adt.bo.Result; U+2U#v=<
n1J;)VyR
/** {Ne5*HFV
* @author Joa
_(1Shm
*/ HBp$
publicinterface UserManager { <7R+p;y
ayK?\srw
public Result listUser(Page page)throws q\]"}M8
vn(ji=
HibernateException; |rr<4>)X
%]1.)j
} jhF&
X5w_ }Nhe
])tUXU>
}{y(&Oy3Y
7*I:cga
java代码: )p!.V(,
=Owr
l'@|T
v-ZTl4j$
/*Created on 2005-7-15*/ -J'0qN!
package com.adt.service.impl; Zc|V7+Yx
Y7_2pGvZ
import java.util.List; DqN<bu2
"
.<>(bE
import net.sf.hibernate.HibernateException; s=[T,:Z
^sqTgrG
import org.flyware.util.page.Page; u}QcyG^
import org.flyware.util.page.PageUtil; U"L7G$
MR3\7D+9y
import com.adt.bo.Result; Y6:b
import com.adt.dao.UserDAO; \qZ>WCp>r
import com.adt.exception.ObjectNotFoundException; J{qsCJiB
import com.adt.service.UserManager; KJ#SE|
e~P4>3
/** T:=ST3#m
* @author Joa b9RJ>K
*/ +Z=%4
publicclass UserManagerImpl implements UserManager { + J` Qv,0
H9%[!
RF
private UserDAO userDAO; cf+EQY
P1qQ)-J
/** aGbHDo
* @param userDAO The userDAO to set. !))!!{
*/ HnsPXF'8g
publicvoid setUserDAO(UserDAO userDAO){ K=N8O8R$y
this.userDAO = userDAO; t/B4?A@C
} Y5z5LG4
|A, <m#C
/* (non-Javadoc) %n@ ^$&,&;
* @see com.adt.service.UserManager#listUser Y?#aUQc
vTsMq>%,<
(org.flyware.util.page.Page) Ou7nk:I@
*/ GFTOP%Tgl
public Result listUser(Page page)throws 8Ao-m38
;q&uk-
HibernateException, ObjectNotFoundException { U
uEm{
int totalRecords = userDAO.getUserCount(); Dt:NBN
if(totalRecords == 0) Iq@&?,W
throw new ObjectNotFoundException Z_Y'
3'^Tw
51gSbkVX
("userNotExist"); 8T5W6Zs1
page = PageUtil.createPage(page, totalRecords); 76(/(v.x
List users = userDAO.getUserByPage(page); !x[].Urj
returnnew Result(page, users); f<y-{.VnN$
} Mi)h<lY
8DGPA
} r)|6H"n#]S
8e"MP\0V
1YScZ
Nh[H[1"J
C Ef*:kr
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 D%~"]WnZ\Q
9Yhlq$;g
询,接下来编写UserDAO的代码: J b?x-%Za
3. UserDAO 和 UserDAOImpl: &t,"k'p
java代码: $bFH%EA.
"@YtxYTW-
tSVU,m
/*Created on 2005-7-15*/ !QlCt>{
package com.adt.dao; 9Ecc~'f
'OI(MuSn
import java.util.List; UK5u"@T
aNUMF
import org.flyware.util.page.Page; p}p}!M|
}6"l`$=Ev
import net.sf.hibernate.HibernateException; FBeo@
N nq r{ub
/** _%KRZx}
* @author Joa rEwd76?
*/ ZxAk
publicinterface UserDAO extends BaseDAO { _[h!r;DsG
t~%( Zu>S
publicList getUserByName(String name)throws q}gM2Ia'vY
L~("C
HibernateException; M'nzoRk
I{i6e'.jP
publicint getUserCount()throws HibernateException; }poLHS/
1v inO!
publicList getUserByPage(Page page)throws GG
%*d]
^G14Z5.
HibernateException; <9]J/w+
eCjyx|:J
} [&sabM`Ul
Ys]cJ]
-_BX\iP{
cq~~a(IS
2oo\ SmO]
java代码: J\hqK*/8
Ze?n Q-
?{%"v\w
/*Created on 2005-7-15*/ 'HJ<"<
package com.adt.dao.impl; 0IyT(1hS
3QCCX$,
import java.util.List; qOflvf
S2
MJb
import org.flyware.util.page.Page; z\-/R9E/5-
Uf9L*Z'6il
import net.sf.hibernate.HibernateException; '.]<lh!
import net.sf.hibernate.Query; LKgo(&mY
<6&Z5mpm$w
import com.adt.dao.UserDAO; q;.LK8M
w\a6ga!xt"
/** S59^$
* @author Joa ujf7r`;u.
*/ M'JCT'(X
public class UserDAOImpl extends BaseDAOHibernateImpl N!./u(b
hjz`0AS
implements UserDAO { p\Fxt1Y@X
3Xm>
3
/* (non-Javadoc) a5 pXn v]A
* @see com.adt.dao.UserDAO#getUserByName gOr%N!5
M7{_"9X{
(java.lang.String) 8On MtP
*/ ?8FJMFv;4%
publicList getUserByName(String name)throws fo~>y
'4}8WYKQ
HibernateException { qWS"I+o,S
String querySentence = "FROM user in class {a]u
,z#S=I
com.adt.po.User WHERE user.name=:name"; wli H3vA_
Query query = getSession().createQuery [-Xah]g
7bQST0 ?
(querySentence); ?kS#g
query.setParameter("name", name); pJIJ"o'>.9
return query.list(); Js^(mRv=
} KE-0/m4yJ
N~P1^x~
/* (non-Javadoc) T.W^L'L`
* @see com.adt.dao.UserDAO#getUserCount() UG3}|\.u
*/ ^].U?t.n)
publicint getUserCount()throws HibernateException { D^6Q`o
int count = 0; '7g]@Q7
String querySentence = "SELECT count(*) FROM }*S`1IWMj
S~)_=4Z
user in class com.adt.po.User"; .)<l69ZD Z
Query query = getSession().createQuery $4Dr +Z
H
sQ+s3x1y
(querySentence); 0"Zxbgu)
count = ((Integer)query.iterate().next ,y@WFRsx
R ^ZOcONd-
()).intValue(); DB}v..
return count; *BvdL:t
} ^$]iUb{\
#J t1AV
/* (non-Javadoc) u>=\.d<
* @see com.adt.dao.UserDAO#getUserByPage F$i 6
39I|.B"
(org.flyware.util.page.Page) <
<F
*/ p_vldTIW
publicList getUserByPage(Page page)throws xVRxKM5 {
*P|~vCnr
HibernateException { P9 y+rF.
String querySentence = "FROM user in class 9@}5FoX"
P=7X+}@
com.adt.po.User"; ^^< C9
Query query = getSession().createQuery
yYrFk^
Y#+Ws0wN
(querySentence); S(/^_Y
query.setFirstResult(page.getBeginIndex()) +VL:O]`DJ
.setMaxResults(page.getEveryPage()); _#
cM vlk
return query.list(); KD]`pqN9
} nm_4E8&X
^=8/I w
} wd3OuDrU
FjMKb
ev4_}!
*9|p}q9n
9_8\xLk
至此,一个完整的分页程序完成。前台的只需要调用 85$ WH
Bd- &~s^
userManager.listUser(page)即可得到一个Page对象和结果集对象 K_k'#j~*?
9|Ylv:sR
的综合体,而传入的参数page对象则可以由前台传入,如果用 Z!*6;[]SfG
bYqv)_8
webwork,甚至可以直接在配置文件中指定。 ;+bF4r@:+
#m;o)KkH$r
下面给出一个webwork调用示例: XN{WxcZ
java代码: u6%\ZK._
\
?9>wG7cps7
]68FGH
/*Created on 2005-6-17*/ .jiJgUa7
package com.adt.action.user; ] ^?w0A
Af r*'
import java.util.List; g<7Aln}Nl\
ia-ht>F*;
import org.apache.commons.logging.Log; ?uU_N$x
import org.apache.commons.logging.LogFactory; $zF%F.rln
import org.flyware.util.page.Page; l]j;0 i
EPR85[k
import com.adt.bo.Result; [Jj@A(Cz
import com.adt.service.UserService; H@9QEj!Y
import com.opensymphony.xwork.Action; u,{R,hTDS
4S4gK
/** pjQyN|KS
* @author Joa ><xmw=
*/ qz2`%8}F)
publicclass ListUser implementsAction{ n5;@}Rai
5ArgM%
privatestaticfinal Log logger = LogFactory.getLog PKC0Dt;F.
VMe
(ListUser.class); 5g
O9 <
m*YfbOhs#
private UserService userService; FnI}N;"
#)@#Qd
private Page page; e\^}PU
G!wb|-4<$
privateList users; 6b$C/
`)4v Q+A>
/* wm Ie x
* (non-Javadoc) nkTdn
* gsUF\4A(J
* @see com.opensymphony.xwork.Action#execute() !YI<A\P
*/ o!U(=:*b
publicString execute()throwsException{ UFu0{rY_
Result result = userService.listUser(page); r=SCbv
page = result.getPage(); Gt
_tL%
users = result.getContent(); q'4P/2)va
return SUCCESS; fD3'Ye<R
} ^,FG9
z] -m<#1
/** T>7N "C
* @return Returns the page. m{$}u@a
*/ {`e-%<
public Page getPage(){ 7a^D[f0V
return page; `M{Ne:J
} t\'MB
[@JK|50|K
/** [\Nmm4
* @return Returns the users. ZJc{P5a1J
*/ r :$*pC&{
publicList getUsers(){ m#i4_F=^b
return users; e|5@7~Vi
} I/!AjB8W4
t&F:C
/** +rA#]#hN
* @param page *uf)t,%
* The page to set. >;R`Q9s7
*/ .MRN)p
publicvoid setPage(Page page){ 5f?GSHA}
this.page = page; *W`7JL,
} uv8kea .(
+P Dk>PdEt
/** RAk"C!&^m
* @param users HV-;?5
* The users to set. I8% -ii
*/ WTM
publicvoid setUsers(List users){ eThFRU3 F
this.users = users; Nnr[@^M5
} %<+uJ'pj
3$q#^UvD
/** GDe,n
* @param userService UKV<Ye|
* The userService to set. x?lRObHK
*/ `LLmdm 6i
publicvoid setUserService(UserService userService){ /5z,G r
this.userService = userService; BD;T>M
} cWZ uph\
} K*2s-,b *
j|`lOH8
r_T"b
r@]`#PL
,x!r^YO=
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, oXqJypR 2
qg1\ABH
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 ,c$tKj5ulQ
ujkWVE'
么只需要: _b>{:H&\
java代码: _-TW-{7bh
27+faR
` OgT"FdL!
<?xml version="1.0"?>
<#57q%
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork X%znNx
4lpcJ+:o
1.0//EN" "http://www.opensymphony.com/xwork/xwork- K]Vp! G
W)J5[p?
1.0.dtd"> cYe2a"
C4d'z(<
<xwork> m;hp1VO)
!G\gqkSL
<package name="user" extends="webwork- mSYm18
}CMGK{
interceptors"> ,7:-V<'Yv
VF";p^
<!-- The default interceptor stack name ~Ey+
^b`-zFL7
--> ;|oft-y
<default-interceptor-ref SCe$v76p#
kZ)}tA7j
name="myDefaultWebStack"/> ^'M^0'_"v
v0! 1W
<action name="listUser" 4e
eh+T
w xte
class="com.adt.action.user.ListUser"> v=hn# U
<param sR83e|4I
R) dP=W*
name="page.everyPage">10</param> mVYfyLZ,(
<result Gos#=H
Qc?W;Q+
name="success">/user/user_list.jsp</result> U9^1A*
</action> ABe25Sus
",vK~m2W_
</package> X=abaKl
]1>R8
</xwork> Br}@Vvq@
NziCN*6
){#INmsF
-ZSN0Xk
z#PaQp5F
v{ohrpb0v
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 sF[gjeIb
YZ8[h`z
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。 |?{V-L
PMbZv%.,-
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 w}OBp^V^
siCm)B
}i^|.VZZ
$.d,>F6
.uS`RS8JM
我写的一个用于分页的类,用了泛型了,hoho 0(f+a_2^Q
=fnBE`Uc
java代码: f sh9-iY8e
5XHejHn>
6.KEe^[-
package com.intokr.util; j[A(@w"
2#^g] o-N
import java.util.List; L8h!%56s
EKF4]
/** _Y&.Nw
* 用于分页的类<br>
H,GjPIG
* 可以用于传递查询的结果也可以用于传送查询的参数<br> &QfEDDJ
* 1`L.$T,1!
* @version 0.01 P)f8lU^z
* @author cheng 2 G*uv+=
*/ ?K:\WW
public class Paginator<E> { u1y>7,Z6W
privateint count = 0; // 总记录数 [fT$# '6
privateint p = 1; // 页编号 ^Ld5<
privateint num = 20; // 每页的记录数 PcT]
privateList<E> results = null; // 结果 ~>9G\/u j
ZpOME@9,
/** >]ux3F3\
* 结果总数 rYdNn0mhk
*/ f9>pMfi:@
publicint getCount(){ pA_u;*
return count; rm3/R<
} |3B<;/v5
q|]CA
publicvoid setCount(int count){ _wb]tE ~g
this.count = count; l#^?sbG
} %regt{
F4T!&E%6
/** N]/cBGy
* 本结果所在的页码,从1开始 Km=
Y^x0
* K*DH_\SPK
* @return Returns the pageNo. \ Xh
C
*/ )6p6<y
publicint getP(){ Nb ~J'"
return p; b,+KXx
} t(roj@!x_o
+3zQ"lLD^
/** [DeDU:
* if(p<=0) p=1 Ty{
SZUJ
* fm^`
* @param p VUUnB<j
*/ <v'[Wl@hq
publicvoid setP(int p){ q#c+%,Z=C
if(p <= 0) aLm~.@Q
p = 1; P
nE7}
this.p = p; 9{A4>
}
*?1\S^7R
Tb2#y]27
/** o*7NyiJ@z
* 每页记录数量 6U8esPs,
*/ sj/k';#g
publicint getNum(){ Jv3G\9_
return num; Gchs$^1`t
} ;Krs*3
s
RiR],Sj
/** Q~wS2f`)
* if(num<1) num=1
wI
7gHp
*/ )ej1)RU"
publicvoid setNum(int num){ ;Qt/(/
if(num < 1) jGkDD8K [
num = 1; s92ol0`
this.num = num; @UdF6:T
} AHuIA{AdUR
#0h}{y
E
/** ;J+iwS*Z
* 获得总页数 1CZO+MB&"$
*/ \/ri|fm6l#
publicint getPageNum(){ O[U`(A:
return(count - 1) / num + 1; @IbZci)1
} .6rbn8h
^4]=D nd%
/** 5K?/-0yG
* 获得本页的开始编号,为 (p-1)*num+1 K>~YO~~
*/ v]Pyz<+
publicint getStart(){ 7uw-1F5x7
return(p - 1) * num + 1; KfVsnL_
} DEkv,e
<a_(qh@B
/** vc3r [mT
* @return Returns the results. 9L-jlAo<
*/ St!0MdCH
publicList<E> getResults(){ T?A3f]U
return results; b[:m[^
} ?771e:>S-
2auJp
.
public void setResults(List<E> results){ $A,YQH+
this.results = results; e&!c8\F
} /TB{|_HbW
FaWc:GsfB
public String toString(){ /!>OWh*~
StringBuilder buff = new StringBuilder 6; )5v
$f+I#uJ
(); NB^Al/V@
buff.append("{"); nW\W<[O9
buff.append("count:").append(count); 4|Y1W}!0/
buff.append(",p:").append(p); 1Lje.%(E.
buff.append(",nump:").append(num); dS Tyx#o
buff.append(",results:").append 0cfGI%
@U?&1.\
(results); %52x:qGa
buff.append("}"); Cq<Lj
return buff.toString();
}#&[[}@th
} 9qGba=}Ey
:,$"Gk
} E^{!B]/oP
*+6iXMwe
(5:pHX`P