Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 {h@\C|nF
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 sQa;l]O:NC
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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 JcR|{9ghT
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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 LpU}.
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分页支持类: `FMo;,j
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java代码: b&U1^{(
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package com.javaeye.common.util; hy*{{f;
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import java.util.List; eWcqf/4?"
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publicclass PaginationSupport { jmID@37t
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publicfinalstaticint PAGESIZE = 30; 0SIC=p=J
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privateint pageSize = PAGESIZE; dH^6K0J
by@KdQow
privateList items; _6NUtU
K3?5bT_{
privateint totalCount; gF{ehU%
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privateint[] indexes = newint[0];
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privateint startIndex = 0; 1ML L
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public PaginationSupport(List items, int %e E^Y<@g
+
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totalCount){ tK%ie\
setPageSize(PAGESIZE); fjRVYOG#
setTotalCount(totalCount); '47
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setItems(items); !g|O.mt
setStartIndex(0); !DZ=`a?y
} UX)GA[WI
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public PaginationSupport(List items, int E=s,-
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totalCount, int startIndex){ H#TkIFo]
setPageSize(PAGESIZE); +`
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setTotalCount(totalCount); ?F"o+]i+^
setItems(items); 7ftn
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setStartIndex(startIndex); QH/py
} GJ,&$@8)
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public PaginationSupport(List items, int 2LwJ%!
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totalCount, int pageSize, int startIndex){ (C!p2f
setPageSize(pageSize); <7^|@L
6
setTotalCount(totalCount); %Rk|B`ST
setItems(items); u&:N`f
setStartIndex(startIndex); =l`)b
} NI V}hf YF
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publicList getItems(){ z#tIa
return items; iq; |
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} C*Vm}|)
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publicvoid setItems(List items){ 6@N,'a8r
this.items = items; 0JlNUO5Nt
} 3( BL
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publicint getPageSize(){ &6x(%o|
return pageSize; '}Fe&%
} (T%F^s5D
pR
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publicvoid setPageSize(int pageSize){ V:n0BlZ,B
this.pageSize = pageSize; a"vzC$Hxd
} Lw>B:3e
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publicint getTotalCount(){ $Rm~ VwY#
return totalCount; Fw<"]*iu
} -b-a21,m>
*S;}&VAZ
publicvoid setTotalCount(int totalCount){ 7>yd
if(totalCount > 0){ W'./p"2g
this.totalCount = totalCount; yYCS-rF>
int count = totalCount / 7Nq<
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pageSize; YdhTjvx
if(totalCount % pageSize > 0) ?H=YJK$k
count++; sVFO&|L
indexes = newint[count]; W:r[o%B
for(int i = 0; i < count; i++){ A!lZyG!3
indexes = pageSize * K.
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i; WyO*8b_
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} |bnd92fvks
}else{ ]v
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this.totalCount = 0; fbq$:Q44
} ziM{2Fs>
} ;(NTzBq!1
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publicint[] getIndexes(){ kF|$oBQ
return indexes;
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} z9o]);dZ
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publicvoid setIndexes(int[] indexes){ !<w6j-S
this.indexes = indexes; S@qPf0dL<
} K"!rj.Da
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publicint getStartIndex(){ @@Q4{o
return startIndex; )PN8HJAArh
} % S312=w
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publicvoid setStartIndex(int startIndex){ g0,~|.
if(totalCount <= 0) 7Jb&~{DVk
this.startIndex = 0; $[T~<I
elseif(startIndex >= totalCount) $JFjR@j
this.startIndex = indexes 2Io|?
0)dpU1B#M
[indexes.length - 1]; (TeH)j!
elseif(startIndex < 0) ~?/7:S
this.startIndex = 0; DI0& _,
else{ $xu2ZBK
this.startIndex = indexes Zo=,!@q(
PF4[;ES'
[startIndex / pageSize]; UynGG@P@
} A;Uc&G
} oiyvKMHz7
!.R-|<2|6
publicint getNextIndex(){ neEqw+#Z
int nextIndex = getStartIndex() + BValU
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pageSize; DwBe_h .
if(nextIndex >= totalCount) e#}t
am
return getStartIndex(); 2f(`HSC'
else d!I%AlV
return nextIndex; `q}D#0
} LW=qX%o{
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publicint getPreviousIndex(){ nDkG}JkB!
int previousIndex = getStartIndex() - (u?s@/e:`/
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pageSize; h%j4(v}r{C
if(previousIndex < 0) 7] y3<t
return0; /qQx~doK
else |6AR!
return previousIndex; Gb^63.}
} i3 js'?7E
h),;j`PrC
} IsE&k2 SD
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抽象业务类 J.~@j;[2
java代码: C?. ;3 h
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/** :$Cm]RZ
* Created on 2005-7-12 !KV!Tkx h
*/ k2Q[v
package com.javaeye.common.business; R5sEQ| E
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import java.io.Serializable; puOMtCI
import java.util.List; +aL6$
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import org.hibernate.Criteria; |mhKD#:
import org.hibernate.HibernateException; 1=]#=)+
import org.hibernate.Session; $bp'b<jx
import org.hibernate.criterion.DetachedCriteria; D u<P^CE
import org.hibernate.criterion.Projections; #mH28UT
import ?3DL .U{
/8Lb_QH{
org.springframework.orm.hibernate3.HibernateCallback; !UzE&CirV
import ,vR>hyM
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org.springframework.orm.hibernate3.support.HibernateDaoS :{w3l O
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upport; z7fX!'3V
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import com.javaeye.common.util.PaginationSupport; ufR|V-BWx
d Np%=gIj
public abstract class AbstractManager extends hbXm Ist
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HibernateDaoSupport { KMT$/I{p,
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privateboolean cacheQueries = false; UHJro9
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privateString queryCacheRegion; 65B&>`H~
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publicvoid setCacheQueries(boolean d/NjY[` 5+
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cacheQueries){ FUI/ A>
this.cacheQueries = cacheQueries; Q8TR@0d
} ruhC:rg:/
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publicvoid setQueryCacheRegion(String D[T\_3W
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queryCacheRegion){ E:}s6l
this.queryCacheRegion = Njo.-k
j+.E#:tu"
queryCacheRegion; uToi4]w"y
} aV fsF|,
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publicvoid save(finalObject entity){ 25G~rklk
getHibernateTemplate().save(entity); VU\G49
} B4OFhtYE
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publicvoid persist(finalObject entity){ 1%@i4
getHibernateTemplate().save(entity); _576Qa'rm
} h6Vd<sV\tf
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publicvoid update(finalObject entity){ }lk9|U#6*`
getHibernateTemplate().update(entity); pJ?y
} ]_>38f7h
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publicvoid delete(finalObject entity){ n~,6!S
getHibernateTemplate().delete(entity); h\C1:0x{
} MO]zf3f!
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publicObject load(finalClass entity, be6`Sv"H
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finalSerializable id){ vSQB~Vw8t
return getHibernateTemplate().load Vl7V?`_4
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(entity, id); JWt@vf~
} #,jm3Mqj
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publicObject get(finalClass entity, %*L8W*V
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finalSerializable id){ zPvTRW~H\
return getHibernateTemplate().get
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(entity, id); F0xm%?
} "t{D5{q|[k
p=Qo92
NH
publicList findAll(finalClass entity){ 2 $Z4 >!
return getHibernateTemplate().find("from ZB}zT9JaE
(Q"s;g
" + entity.getName()); 3qfQlqJ&3
} 7n#Mh-vq
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publicList findByNamedQuery(finalString ]{-ib:f~
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namedQuery){ kKQD$g.z6
return getHibernateTemplate %e:
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().findByNamedQuery(namedQuery); f+Bv8 g
} QswFISch
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publicList findByNamedQuery(finalString query, !;PKx]/&
0@!-+}i
finalObject parameter){ =rNI&K_<
return getHibernateTemplate LZPLz@=&]
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().findByNamedQuery(query, parameter); w="
} K?wo AuY
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publicList findByNamedQuery(finalString query, H|N,nkhH}
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finalObject[] parameters){ 4!+IsT
return getHibernateTemplate jW|M)[KJN
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().findByNamedQuery(query, parameters); %tz foiJ%P
} y#{> tC
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publicList find(finalString query){ |A
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return getHibernateTemplate().find j|WN!!7
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(query); -[lOf
} K30{Fcb< h
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publicList find(finalString query, finalObject ,3ivB8
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parameter){ XuW>GT/
return getHibernateTemplate().find )e\IdKl=
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(query, parameter); XCZNvLG
} /`B:F5r
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public PaginationSupport findPageByCriteria v+2t;PJd2
2HREO@._)
(final DetachedCriteria detachedCriteria){ ON3~!Q)
return findPageByCriteria (^Hpe5h&
z/S}z4o/
(detachedCriteria, PaginationSupport.PAGESIZE, 0); bu r0?q
} ]$WwPDZ
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public PaginationSupport findPageByCriteria jUX0sRDk
czp}-{4X
(final DetachedCriteria detachedCriteria, finalint w`K=J!5y2g
[Gb8o'
startIndex){ r`CsR0[
return findPageByCriteria w>gB&59r
~@Eu4ip)F
(detachedCriteria, PaginationSupport.PAGESIZE, f>_' ]eM%
Y]{~ogsn$:
startIndex); 1lQO`CmR6M
} \ssqIRk
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public PaginationSupport findPageByCriteria 2~*.X^dR
eB*0})
(final DetachedCriteria detachedCriteria, finalint B=+Py%
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pageSize, >a2i%j/T
finalint startIndex){ Sy`7 })[
return(PaginationSupport) 5"9!kZ(<
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getHibernateTemplate().execute(new HibernateCallback(){ iwnFCZVS
publicObject doInHibernate /jv4#9
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(Session session)throws HibernateException { 6{PlclI !
Criteria criteria = -|A`+1-R+
q*4=sf,>
detachedCriteria.getExecutableCriteria(session); q'[q]
int totalCount = vTU*6)
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((Integer) criteria.setProjection(Projections.rowCount hE>%LcP
nhP ua&
()).uniqueResult()).intValue(); ,O/ t6'
criteria.setProjection iqPMCOPZ
+(3U_]Lu
(null); :NPnwX8w
List items = E#m|Sq
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criteria.setFirstResult(startIndex).setMaxResults P<A_7Ho
2^$Ha|
(pageSize).list(); `8D}\w<eI
PaginationSupport ps = 'l*p!=
S
7 *LV;
new PaginationSupport(items, totalCount, pageSize, kls
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'9d]
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startIndex); =;?afUj
return ps; (7_}UT@w-
} 3c.,T
}, true); ^9*kZV<K
} Pwg?a
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public List findAllByCriteria(final '6zD`Q
B)}.%G*
DetachedCriteria detachedCriteria){ -kz9KGkPb+
return(List) getHibernateTemplate U}2b{
&;]KntxB
().execute(new HibernateCallback(){ -'mTSJ.}
publicObject doInHibernate I8:A]
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(Session session)throws HibernateException { RO+N>Wkt
Criteria criteria = OkaNVTB
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detachedCriteria.getExecutableCriteria(session); H!yqIh
return criteria.list(); /f0*NNSat-
} ~dc~<hK
}, true); VuWBWb?0Q
} R+y 9JE
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public int getCountByCriteria(final yO`HL'SMo
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DetachedCriteria detachedCriteria){ C=>IJ'G
Integer count = (Integer) [uD G;We=
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getHibernateTemplate().execute(new HibernateCallback(){ R
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publicObject doInHibernate 14
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(Session session)throws HibernateException { i~0x/wSl_
Criteria criteria = 3"HW{=
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detachedCriteria.getExecutableCriteria(session); H%z9VJ*!0
return waI:w,
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criteria.setProjection(Projections.rowCount +<1MY'>y
sOUQd-!"
()).uniqueResult(); nWz7$O
} ;S.o`z1GI
}, true); kzuI<DW
return count.intValue(); .ZK^kcyA
} s7>a
} A4>j4\A[M
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用户在web层构造查询条件detachedCriteria,和可选的 j| Hyv{sM
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 e"O c
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PaginationSupport的实例ps。 !xxdC
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ps.getItems()得到已分页好的结果集 aoP=7d|K/
ps.getIndexes()得到分页索引的数组 QxI^Bx
ps.getTotalCount()得到总结果数 <tx`#,
ps.getStartIndex()当前分页索引 *'ffMnSZ
ps.getNextIndex()下一页索引 r(6$.zx
ps.getPreviousIndex()上一页索引 a
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 nc/F@HCB
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 gHmy?+)
(29BS(|!
一下代码重构了。 F+Q(^Nk
thK4@C|X4
我把原本我的做法也提供出来供大家讨论吧: fx3oA}
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首先,为了实现分页查询,我封装了一个Page类: =Hf`yH\#
java代码: Lh
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/*Created on 2005-4-14*/ 6s(.ul
package org.flyware.util.page; %&}gt+L(M
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4
/** vMv?
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* @author Joa f)#rBAkt
* eB2a1<S&@
*/ R.P|gk
publicclass Page { q'1
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8ZL9>"%l
/** imply if the page has previous page */ X(M|T]`b:
privateboolean hasPrePage; - xKa-3
gPqdl6#c
/** imply if the page has next page */ =s/UF _JN
privateboolean hasNextPage; we}G%09L
'<-F3
/** the number of every page */ 'gv~M_
privateint everyPage; y1Op Z
_?rL7oTv
/** the total page number */ nv'YtmR
privateint totalPage; ![Ll$Lr
B`mTp01
/** the number of current page */ 8'|_O
privateint currentPage; q>f|1Pf
fq4[/%6,O
/** the begin index of the records by the current h;DLD8L
Zt/4|&w
query */ m4x8W2q
privateint beginIndex; iOXsj
hZwJ@ Vm#
,
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/** The default constructor */ >eM>Y@8=
public Page(){ N.F//n
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} 5-2#H?:U
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/** construct the page by everyPage /v8yE9N_
* @param everyPage Yc p<N>)
* */ P TMJ.;
public Page(int everyPage){ s~>0<3{5
this.everyPage = everyPage; W'" p:Uhq
} B0$ge"FK9
|* v w(
/** The whole constructor */ @ebSM#F?
public Page(boolean hasPrePage, boolean hasNextPage, uq\[^
Mem1X rBH
&e)V!o@wJV
int everyPage, int totalPage, P&sYS<9q
int currentPage, int beginIndex){ B2T=O %
this.hasPrePage = hasPrePage; [DD#YL\P
this.hasNextPage = hasNextPage; ioJ|-@!#o
this.everyPage = everyPage; #,CK;h9jy!
this.totalPage = totalPage; "|nh=!L
this.currentPage = currentPage; (8Q*NZ
this.beginIndex = beginIndex; Zonr/sA ~
} IutU~%wv
/zg|I?$>Z4
/** L['g')g.
* @return * _@t$W
* Returns the beginIndex. Ex-?[Hq
*/ 0 HPqoen$
publicint getBeginIndex(){ bwyj[:6l
return beginIndex; N}CeQ'l[R
} .1YiNmW=
w^E$R
/** HyC826~-rI
* @param beginIndex @&9 ,0x
* The beginIndex to set. RfQ*`^D
*/ ]=]fIKd
publicvoid setBeginIndex(int beginIndex){ FwwOp"[~t
this.beginIndex = beginIndex; |m F=X*
} (-%1z_@Y
2P,{`O1]
/** uWjEyxPv{
* @return Uu0
* Returns the currentPage. t{Wu5<F:
*/ )NmYgd~%
publicint getCurrentPage(){ K;lxPM]
return currentPage; f^|r*@o
} j]'ybpMT"
xz3|m
_)
/** cP^c}e*;NS
* @param currentPage ,;)_$%bHc
* The currentPage to set. qQp;i{X
*/ }9~U5UXWU
publicvoid setCurrentPage(int currentPage){ S<81r2LT
this.currentPage = currentPage; se*!OiOt
} 2Dw}o;1'
X}ft7;Jpy
/** D9%t67s
* @return )QW
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* Returns the everyPage. ZmAo9>'Kg
*/ @ n^2UJ
publicint getEveryPage(){ q{uv?{I
return everyPage; gt\*9P
} tvcM<
e20
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/** F*p@hl
* @param everyPage mWTV)z57
* The everyPage to set. Xq%ijo
*/ Ma^}7D
/
publicvoid setEveryPage(int everyPage){ 5%]O'h
this.everyPage = everyPage; +wGFJLHJ
} `]4tJJy$
`M!'PMX
/** Vc!'=&*
* @return wxE'h~+
* Returns the hasNextPage. NX8.
\Pf#
*/ 46D_K
publicboolean getHasNextPage(){ @umn[J#*
return hasNextPage; 4P?R "Lk
} GP0}I@>?
$_O;yz
/** 0?*":o30
* @param hasNextPage d@ef+-
* The hasNextPage to set. q"VC#97`
*/ jqQG n"!
publicvoid setHasNextPage(boolean hasNextPage){ m[<z/D
this.hasNextPage = hasNextPage; G2w0r,[
} -u~AY#*
n!h952"
/** d,E2l~s
* @return #D^(dz*
* Returns the hasPrePage. VJS1{n=;k
*/ "0m\y+%8
publicboolean getHasPrePage(){ $GQ{Ai:VwF
return hasPrePage; />O.U?
} i QvqifDmh
M3s:B& /
/** ,U.|+i{
* @param hasPrePage <~
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* The hasPrePage to set. x.>&|Ej
*/ UV\&9>@L
publicvoid setHasPrePage(boolean hasPrePage){ HXgf=R/$
this.hasPrePage = hasPrePage; z6Zd/mt~x
} P\&n0C~
>:|jds#
/** 7~H"m/;U&
* @return Returns the totalPage. a0PClbf2.
* 8gW$\
*/ JfzfxfM
publicint getTotalPage(){ $KPf[JvQ
return totalPage; +r$VrNVs
} /2Bf6
[Q[ac 6f
/** rTzXRMv@o
* @param totalPage QeQxz1
* The totalPage to set. z'}z4^35,
*/ @+hO,WXN
publicvoid setTotalPage(int totalPage){ b&!x.+d-z
this.totalPage = totalPage; 9>ML;$T&
} P.3kcZ
P(B&*1X
} EO\- J-nM
& sgzSX
QJ,~K&?
U]"6KS
t:%u4\nZ;
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 dC?l%,W
9PG3cCr?
个PageUtil,负责对Page对象进行构造: (t"e#b(:
java代码: f<vZ4 IU
:8Ugz ~i
m0 ]Lc{
/*Created on 2005-4-14*/ 1 Ay.^f
package org.flyware.util.page; KNSMx<GP
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~183
import org.apache.commons.logging.Log; <
;fI*km
import org.apache.commons.logging.LogFactory; +@MG$*}Oz
Fr hI[D
/** <AB({(
* @author Joa @+Anp4%;Y
* HjT -5>I7f
*/ iz2;xa*
publicclass PageUtil { 9n;6;K#
c. uD%
privatestaticfinal Log logger = LogFactory.getLog xd!GRJ<I
7o9[cq w
(PageUtil.class); m 3Do+!M[
ese?;1r
/** jBJ|%KM
* Use the origin page to create a new page MZ_dI"J,
* @param page d[sY]_ dj
* @param totalRecords VujIKc#4
* @return
m">2XGCn
*/ yK w.69.
publicstatic Page createPage(Page page, int vgN%vw pL
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totalRecords){ O[ug7\cl+
return createPage(page.getEveryPage(), mBDzc(_\$'
s$xm
page.getCurrentPage(), totalRecords); &'c&B0j
} oA4<AJ2
1(qL),F;
/** ap[Q'=A`
* the basic page utils not including exception >Dq&[9,8
~X,ZZ 9H
handler Ki\J)l
* @param everyPage y~<_ux,
* @param currentPage LuWY}ste
* @param totalRecords t{O2JF#5u
* @return page -fD W>]_
*/ 5c1{[
publicstatic Page createPage(int everyPage, int ,Ofou8C6
!$#8Z".{v{
currentPage, int totalRecords){ P.kf|,8L
everyPage = getEveryPage(everyPage); `FAZAC\
currentPage = getCurrentPage(currentPage); y>&
s;
int beginIndex = getBeginIndex(everyPage, ]Mj N)%hT
#yOn /
currentPage); f&?
8fB8{
int totalPage = getTotalPage(everyPage, a4eE/1
)
-@Dh6F
totalRecords); #g]eDU-[
boolean hasNextPage = hasNextPage(currentPage, hv )d
wcW}Sv[r
totalPage); ]
jycg@=B
boolean hasPrePage = hasPrePage(currentPage); vzZ"TSP
6 IKi*}
returnnew Page(hasPrePage, hasNextPage, I~25}(IDZ"
everyPage, totalPage, ]GXE2A_i;
currentPage, PGA
`R
+g%Ah
beginIndex); #fxdZm,
} I GB)
]%[. > mR
privatestaticint getEveryPage(int everyPage){ JjQ9AJ?-V
return everyPage == 0 ? 10 : everyPage; (w?W=guHu
} zI'c 'X1,
92Rm{n
privatestaticint getCurrentPage(int currentPage){ [[KIuW~ot
return currentPage == 0 ? 1 : currentPage; |L~RC
} PB!*&T'!
.gA4gI1kH
privatestaticint getBeginIndex(int everyPage, int 7
'{wl,u
5>&C.+A 9
currentPage){ ^']*UD;
return(currentPage - 1) * everyPage; td|O #R
} XO}v8nWV
bP{uZnOM2P
privatestaticint getTotalPage(int everyPage, int ~4M?[E&
d*Kg_He-
totalRecords){ _OJ19 Ry
int totalPage = 0; 0-8'.C1v
xcQ:&q
if(totalRecords % everyPage == 0) n(jrK9]
totalPage = totalRecords / everyPage; |4F'Zu}g>
else ,zh4oX`>
totalPage = totalRecords / everyPage + 1 ; 3|0OW
Jk
}N@+bNh~
return totalPage; }Pj;9ivz
} &Tk@2<5=
@!%HEs!# #
privatestaticboolean hasPrePage(int currentPage){ 2,G9~<t
return currentPage == 1 ? false : true; n hGh5,
} y-)5d
z_ L><}H
privatestaticboolean hasNextPage(int currentPage, B{ cb'\C
3=IY0Q>/(
int totalPage){ H`NT`BE
return currentPage == totalPage || totalPage == Vn6]h|vm
!p(N
DQm
0 ? false : true; Ky)*6QOw
} ^zR*s |1Q
vSGvv43G
S0tPnwco[~
} B q7Qbj
*w6(nG'M{
_[S<Cb*1
AI2@VvB
Kl w9
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。 -Ps kUl'
zE]h]$oi
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 =Y-mc#{8
1IWP~G
做法如下: =yLJGNK[
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 HI{IC!6
nmUMg
的信息,和一个结果集List: )"f*Mp
java代码: B-[qS;PY%
P30|TU+B
pFwhvw
/*Created on 2005-6-13*/ O
718s\#
package com.adt.bo; w>6cc#>q
q 1+{MPJ
import java.util.List; 4_h?E:sBb
KNqs=:i
import org.flyware.util.page.Page; 5VGr<i&A
`_>44!M
/** ^"EK:|Y4%K
* @author Joa yn.f?[G2
*/ <{1=4PA
publicclass Result { VU\{<j{
X&cm)o%5Fe
private Page page; g)^g_4
M]A!jWtE
private List content; YCo qe,5
t? [8k&Z
/** v42Z&PO
* The default constructor L'<.#(|
*/ d`4F
public Result(){ U t.#h="
super(); 'Sjt*2blq
} zAO|{m<A2
hbE~.[Y2r
/** 3V@!}@y,F6
* The constructor using fields 6}GcMhU<r
* .X{U\{c| a
* @param page aui3Mq#f
* @param content (zIIC"~5
*/ f"0?_cG{%
public Result(Page page, List content){ O@sJ#i>
this.page = page; a_o99lP
this.content = content; z9HUI5ns
} v?`DP
kr>F=|R]
/** TV*@h2C"i
* @return Returns the content. E{}Vi>@V?
*/ Qk`LBvg1
publicList getContent(){ 4pZ=CB+j
return content; 2t`d.s=
} R![4|FR
>2dF^cDE-3
/** vlh$NK+F
* @return Returns the page. m-XS_5x\
*/ Vv3:x1S
public Page getPage(){ =;y(b~
return page; xaW9Sj0ZM
} X"O^4MnvI
Q7XlFjzcm
/** {V5eHn9/Q'
* @param content 5FwVR3,
* The content to set. FP9FE `x
*/ btWvoKO*
public void setContent(List content){ do=s=&T
this.content = content; HiTj-O
} >PONu]^
wUcp_)aE|
/** 5yQ\s[;o3
* @param page _p\O!y
* The page to set. #w&N)
c>
*/ .0iHI3i^
publicvoid setPage(Page page){ b]Z>P{ j
this.page = page; q,*([yX
} v7G&`4~
} tzdh3\6F
]j57Gk%z
uZ8^" W
f/{*v4!
A,]%*kg2
2. 编写业务逻辑接口,并实现它(UserManager, OzS/J;[PO[
\I
#}R4z
UserManagerImpl) W;!)Sj4<T!
java代码: A7=k9|
<K
GYwLk
d{:0R9
/*Created on 2005-7-15*/ a F%V
package com.adt.service; 7V-'><)gI
!7jVKI80
import net.sf.hibernate.HibernateException; dI)
9@UL
X^9eCj;c
import org.flyware.util.page.Page; ":V,&o9n
\2VYDBi?|
import com.adt.bo.Result; y sFp`
N=~aj7B%
/** .ly K
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* @author Joa ZOY zCc(d
*/ GLr7sack
publicinterface UserManager { (V9 ;
b?nORWjC
public Result listUser(Page page)throws D=:O^<
j/uu&\e
HibernateException; 2^4OaHY88
vmIt!x
} Rxk0^d:sNi
i;mA|
C}Ucyzfr,p
.+$ox-EK8
H/N4tWk"
java代码: ^Rc*X'Iz(!
~9DD=5\
SCo; Ek
/*Created on 2005-7-15*/ (.N!(;G
package com.adt.service.impl; }-H)jN^
>S'IrnH'!
import java.util.List; S0mzDLgE
^!sIEL
import net.sf.hibernate.HibernateException; .vWwYG
YK%rTbB(
import org.flyware.util.page.Page;
95l)w
import org.flyware.util.page.PageUtil; gt)wk93d>
WWG+0jQ9
import com.adt.bo.Result; ]1&}L^a
import com.adt.dao.UserDAO; 9N V.<&~
import com.adt.exception.ObjectNotFoundException; p d(W(-`8!
import com.adt.service.UserManager; oxXCf%!
$c }-/U 8
/** #8@o%%Fd
* @author Joa 2+cpNk$
*/ @23~)uiZa
publicclass UserManagerImpl implements UserManager { R/Z
zmb{
d34BJ<
private UserDAO userDAO; HMqR%A
MkX=34oc^
/** }0~X)Vgm(
* @param userDAO The userDAO to set. 2VaKt4+`
*/ ]3]=RuQK2
publicvoid setUserDAO(UserDAO userDAO){ 3H,?ZFFGz
this.userDAO = userDAO; J/B`c(
} (0u(<qA\
66-G)+4
/* (non-Javadoc) R(p3*t&n
* @see com.adt.service.UserManager#listUser U6F1QLSLz
Cxra(!&
(org.flyware.util.page.Page) "? ON0u9
*/ 5%RiM|+
public Result listUser(Page page)throws }va>jfy
yoG*c%3V?
HibernateException, ObjectNotFoundException { 4}F~h
int totalRecords = userDAO.getUserCount(); ?tx."MZ
if(totalRecords == 0) j9~lf
throw new ObjectNotFoundException
]Gf`nJDV
lb\VQZp!y
("userNotExist"); .JX9(#Uk
page = PageUtil.createPage(page, totalRecords); DhD^w;f]
List users = userDAO.getUserByPage(page); do:IkjU~
returnnew Result(page, users); ?}"39n
} cG,zO-H
r$W%d[pB
} /X%+z5
KvXFzx|A
-; *lcY*
+F+M[ef<ws
UX%J?;g
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 45;ey }8
_BZ6Ws$C2
询,接下来编写UserDAO的代码: uYC1}Y5N
3. UserDAO 和 UserDAOImpl: nYE%@Up
java代码: OXI>`$we
;b!qt-;.<
DB3qf>@?
/*Created on 2005-7-15*/ Uj)Wbe[)p0
package com.adt.dao; ~3Y4_b5E
GQ2/3kt
import java.util.List; Y`rli
nt8&Mf
import org.flyware.util.page.Page; L}6!D zl
9qUkw&}H
import net.sf.hibernate.HibernateException; fwNj@fl_,e
0+F--E4
/** 8kT`5`}lB
* @author Joa `IT]ZAem`/
*/ vUhgM'
publicinterface UserDAO extends BaseDAO { i!)\m0Wm
oI-,6G}
publicList getUserByName(String name)throws ($-m}UF\/
2P ^x'I
HibernateException; Raf(m,o(
-\n%K
publicint getUserCount()throws HibernateException; %`*On~
us+z8Mz
publicList getUserByPage(Page page)throws JJK-+a6cX
Rqr>B(|
HibernateException; bvS6xU-
J
3~:9ZWQ/
} J4u>77I
</2 aQn
O L 9(~p
et?FX K"y
wf`A&P5tF
java代码: d,toU I
l=ZD&uK
d/!\iLF
/*Created on 2005-7-15*/ mM:%-I\$
package com.adt.dao.impl; -e"A)Bpl(
tAsap}(
import java.util.List; 3g3f87[
[iZH[7&j
import org.flyware.util.page.Page; DLuaM?7
2M=h:::W
import net.sf.hibernate.HibernateException; :C2
@!W
z
import net.sf.hibernate.Query;
1D_&n@
-Nn<pq
import com.adt.dao.UserDAO; eph2&)D}Ep
G"w
[>m
/** [:uHe#L
* @author Joa "c\WZB`|
*/ hfw+n<
public class UserDAOImpl extends BaseDAOHibernateImpl QiK-|hFj
F?[1m2
implements UserDAO { !o1IpTN
83 <CDjD
/* (non-Javadoc)
HQ]mDo
* @see com.adt.dao.UserDAO#getUserByName c0Pj})-
05g %5vHF
(java.lang.String)
sC0u4w>Y
*/ @dx8 {oQ
publicList getUserByName(String name)throws U$Z<lx2P
7Mk>`4D'c
HibernateException { #ID
fJ2
String querySentence = "FROM user in class *jvP4Nz)k
|1zfXG,R
com.adt.po.User WHERE user.name=:name"; FPH2dN
Query query = getSession().createQuery @yo6w}3+-
4EmdQn
(querySentence); Lq;T\m_de
query.setParameter("name", name); iD*Hh-
return query.list(); e9HL)=YP
} [$;cjys
v>j,8E
/* (non-Javadoc) @Pf9;7,TV
* @see com.adt.dao.UserDAO#getUserCount() {*P[dyu
*/ 8d_J9Ho
publicint getUserCount()throws HibernateException { 7F2 RH 8 )
int count = 0; ` Nf
String querySentence = "SELECT count(*) FROM I=:"Fqj'N
|L`U2.hb
user in class com.adt.po.User"; >I/@GX/
Query query = getSession().createQuery ;!G#Y
Oe
$v #
(querySentence); bX$1PYX
count = ((Integer)query.iterate().next j1A%LS;c_
dNhbvzl(
()).intValue(); = pn;b1=
return count; 1Iy1xiP
} AwjXY,2
ZuybjV1/f6
/* (non-Javadoc) [NAfy~X*
* @see com.adt.dao.UserDAO#getUserByPage rZ|p{ym
]E$NJq|
(org.flyware.util.page.Page) vbn=ywz
*/ kDDC@A $
publicList getUserByPage(Page page)throws \Oq8kJ=
*hru);OJr
HibernateException { g$^-WmX\m
String querySentence = "FROM user in class ~TsRUT
/#
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com.adt.po.User"; wN58uV '
Query query = getSession().createQuery Hy1$Kvub
}Nd1'BVf
(querySentence); >}\s-/
query.setFirstResult(page.getBeginIndex()) >$TvCw
.setMaxResults(page.getEveryPage()); 9TQVgkW
return query.list(); |9=A"092{
} &+&@;2
Z|Oq7wzEH
} #>("(euXMF
f}"eN/T
3>^]r jFw
Y!_{:2H8p
PPH;'!>s"
至此,一个完整的分页程序完成。前台的只需要调用 ch:rAx
Sc/l.]k+
userManager.listUser(page)即可得到一个Page对象和结果集对象 u*):
D~A
} 6!/Nb
的综合体,而传入的参数page对象则可以由前台传入,如果用 kl]MP}wc
h x&"f e
webwork,甚至可以直接在配置文件中指定。 |T@SlNi]
|=*)a2
下面给出一个webwork调用示例: v@tEHRadz
java代码: gT0yI;g]
:;.^r,QAI
D\b$$z]q
/*Created on 2005-6-17*/ 51b%uz
package com.adt.action.user; )ds]fvMW]N
:ujpLIjvVG
import java.util.List; :CW^$Zvq
Vj 9X6u}{
import org.apache.commons.logging.Log; \cCH/
import org.apache.commons.logging.LogFactory; (;;ji!i
import org.flyware.util.page.Page; ;b*qunJ3L
]t~.?)Ad+2
import com.adt.bo.Result; tiE|%jOzt
import com.adt.service.UserService; 5{k,/Z[L
import com.opensymphony.xwork.Action; 'E9{qPLk(
h{iuk3G`h6
/** wpuK?fP
* @author Joa 6ICW>#fI`
*/ !#_2 ![
publicclass ListUser implementsAction{ 'mbLK#q
hdCd:6
privatestaticfinal Log logger = LogFactory.getLog ofV0L
F`m}RL]g
(ListUser.class); babL.Ua8o
-yBKA]"<I
private UserService userService; &H%/.4la
Z::I3 Q
private Page page; ,\iHgsZ
+4_, , I
privateList users; ~q}L13^k
QR#>Ws
/* G|f9l?p
* (non-Javadoc) wQUl!s7M;
* < ,0D|O,Y
* @see com.opensymphony.xwork.Action#execute() h;jO7+W
*/ ah:["< z<
publicString execute()throwsException{ |Q3d7y
Result result = userService.listUser(page); } 7
o!
page = result.getPage(); ]|tg`*l!>
users = result.getContent(); I U"
return SUCCESS; MGm*({%
} )1 T2u
O|,9EOrP
/** p?y2j
* @return Returns the page. o13jd NQ-
*/ ")Not$8
public Page getPage(){ +Pb:<WT}%
return page; 'JMW.;Lh?X
} yO1
7C
g,._3.D
/** ESRj<p%W
* @return Returns the users. x^[,0?y2
*/ 6]b"n'G
publicList getUsers(){ aNEah
return users; uKP4ur@1
} FSA%,b;U
\uOM,98xS
/** '_G\_h}5
* @param page Ahwi
* The page to set. sWo`dZ\6WB
*/ |ZH(Z}m
publicvoid setPage(Page page){ -p_5T*R
this.page = page; A+RW=|:
} UmWXv#q\l
h5'hP>b#
/** ^1.*NG8
* @param users m}wn+R
* The users to set. TM(y%!\
*/ -_ I)5*N
publicvoid setUsers(List users){ D8wf`RUt
this.users = users; C12UZE;
} ae sk.
a
~v$ bNu
/** G^W0!u,@
* @param userService 89LD:+p/
* The userService to set. fQa*> **j;
*/ B[@q.n
publicvoid setUserService(UserService userService){ %42a>piev
this.userService = userService; %LMpErZO
} +Umsr
} R|C`
tr<fii3<
`HRL .uX
e%JIqKS
h+1|.d
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, skcyLIb
`MSig)V
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 M4C8K{}
@vlP)"
么只需要: 5j`xSG
java代码: <}RI<96
n>ui'}L
TF/NA\0c$
<?xml version="1.0"?> v@Uk% O/
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork }pMVl
VC88re`
1.0//EN" "http://www.opensymphony.com/xwork/xwork- .kBkYK8*t
<t"T'\3
1.0.dtd"> V6][*.i!9
[;z\bV<S
<xwork> *<xu3){:c
Qfm$q~`D^W
<package name="user" extends="webwork- ^Lgvey%
e-ta 7R4
interceptors"> -"I$$C
jhm3:;Z
<!-- The default interceptor stack name c#N4XsG,
lr>NG,N
--> d%8n
<default-interceptor-ref @A1f#Ed<
G JRl{Y
name="myDefaultWebStack"/> _X4Y1zh
S $p>sItO
<action name="listUser" eyMn! a
a* cWj}u
class="com.adt.action.user.ListUser"> cz9J&Le>
<param 0~ho/ _
zzf@U&x<
name="page.everyPage">10</param> E#KZZ lbx
<result r
W`7<3
5b}w
name="success">/user/user_list.jsp</result> nEsD+}E?
</action> zo ?RFn
|0i{z(B
</package> [MpWvLP"x
7
XxZF43
</xwork> F$as#.7FF
X
hq ss),
H@uu;:l<7A
x2B8G;6u
;|Mfq`s
WA(x]""
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 0 %~~IT}U
\V$qAfP)
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 \AwkK3
n2mO-ZXud
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 H4y9\
-
lJdBUoO
(fF8)4l
wo0j/4o
K KB+o)*W
我写的一个用于分页的类,用了泛型了,hoho 6MVu"0#
vS8&,wJ!
java代码: 3xy2ZYw
f5V-;
v])ew|
package com.intokr.util; i{6&/TBnr
"UTW(~D'
import java.util.List; Xq;|l?,O
@ual+=L
/** yu'-'{%
* 用于分页的类<br> 4Im>2)
* 可以用于传递查询的结果也可以用于传送查询的参数<br> -hXKCb4YU
* T aS1%(
* @version 0.01 KkCGL*]K
* @author cheng @U_CnhPQq
*/ ef`_
n+`
public class Paginator<E> { `<nxXsLe
privateint count = 0; // 总记录数 gq?7O<
privateint p = 1; // 页编号 G<7M;vRvP
privateint num = 20; // 每页的记录数 2f[;U"
privateList<E> results = null; // 结果 WLl8oE<X
M@xU59$@
/** C+TB>~Gv`
* 结果总数 Y%?S:&GH
*/ `q36`Wn
publicint getCount(){ 'f<N7%eZ
return count; s\;/U|P_
} w0~%,S
@R5^J{T
publicvoid setCount(int count){ e\V
-L_
this.count = count; \U$:/#1Oe
} v[Q)L!J1
i#la'ICwJ
/** O >h`
* 本结果所在的页码,从1开始 I0+6p8,
* %M
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* @return Returns the pageNo. CGi;M=xr
*/
;2C
publicint getP(){ 5GM-*Ak @
return p; ,>-j Ztm
} !h.hJt
HV~Fe!J_
/** xxur4@p!
* if(p<=0) p=1 8oJl ]
* [#Qf#T%5h
* @param p ^sf,mM~D
*/ 7+P;s,mi7
publicvoid setP(int p){ M{L- V
if(p <= 0) s`$}xukT
p = 1; &3t973=
this.p = p; H7Q$k4\l
} (\F9_y,6*\
1b%Oi.;
/** (I~
* 每页记录数量 tczJk1g}
*/ <iky~iE
publicint getNum(){ /wLBmh1"
return num; x@OBGKV
} %D4)Bqr
dL$ iTSfz"
/** ;z4J)qw
* if(num<1) num=1 i%FC
lMF
*/ MDF_Xr-hZ
publicvoid setNum(int num){ O(/~cQ
if(num < 1) KA?}o^-F
num = 1; 86{>X5 +
this.num = num; j,i9,oF6]
} vxZ'-&;t
&x1A{j_
/** Lng. X8D
* 获得总页数 GNJ/|9
*/ M 2hZ'
publicint getPageNum(){ un 5r9
return(count - 1) / num + 1; ~LS</_N
} iE'' >Z
T_S3_-|{==
/** +;~N; BT
* 获得本页的开始编号,为 (p-1)*num+1 WAxNQfEe
*/ (vG*)a
publicint getStart(){ 46g0
e
return(p - 1) * num + 1; 'JOCL0FP
} gO8d2?Oh
-yf8
/** _
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* @return Returns the results. $BdwKk
!k
*/ uA#K59E+
publicList<E> getResults(){ _z#"BN
return results; ~3.*b%,
} qKD
0''p29
public void setResults(List<E> results){
P\MDD@
this.results = results; Q` u#
} "kP,v&n
gL_1~"3KGC
public String toString(){ W/,bz",v3
StringBuilder buff = new StringBuilder 1O`V_d)
)c4tGT<
(); YD[HBF)~j
buff.append("{"); 5[4wN(
)
buff.append("count:").append(count); qHub+"2
buff.append(",p:").append(p); _|u}^MLO
buff.append(",nump:").append(num); AJ}FHym_ZQ
buff.append(",results:").append v/ N[)<
Ro]Z9C>1o
(results); Yk|6?e{+)
buff.append("}"); +g
g_C'"
return buff.toString(); !CU-5bpu
} DU\ytD`u
KyNu8s k
} K[icVT2v~
Q/SO%E`E
)Dz]Pv]H'