Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ;@|n @ax
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 N5b!.B x-w
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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 @r/nF5
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 %M|hA#04vZ
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。 _>X+ZlpU:
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分页支持类: eV?2LtT#5
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java代码: J{fH['tzO
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package com.javaeye.common.util; 338k?nHxv
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import java.util.List; p4
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publicclass PaginationSupport { %aVq+kC h
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publicfinalstaticint PAGESIZE = 30; |H+UOEiv,p
8NAON5.!
privateint pageSize = PAGESIZE; PBTnIU
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privateList items; *mvlb
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privateint totalCount; E92KP?i
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privateint[] indexes = newint[0]; |imM#wF
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privateint startIndex = 0; }*pi<s
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public PaginationSupport(List items, int aQ\$A`?
:(*V?WI
totalCount){ K:#I
setPageSize(PAGESIZE); a'yK~;+_9
setTotalCount(totalCount); ML56k~"BL
setItems(items); dk4CpN
setStartIndex(0); x\G'kEd
} o9yJf#-En
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public PaginationSupport(List items, int z/2//mM
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totalCount, int startIndex){ 3eAX.z`D
setPageSize(PAGESIZE); }Sh?S]]`
setTotalCount(totalCount); mLLDE;7|}
setItems(items); V#gK$uv
setStartIndex(startIndex); C7ScS"~
} 84zSK)=Y
B!L{
public PaginationSupport(List items, int rlSeu5X6
<
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totalCount, int pageSize, int startIndex){ ['tY4$L(
setPageSize(pageSize); SP_75BJ
setTotalCount(totalCount); R=2FNP
setItems(items); !@*7e:l
setStartIndex(startIndex); `%"\@<
} #r~# I}U
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publicList getItems(){ '/p/8V.O.
return items; .:%0E`E
} Zaf:fsj>
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publicvoid setItems(List items){ 9Uekvs=r=M
this.items = items; 2*l/3VW
} bUdLs.:
Q1I6$8:7
publicint getPageSize(){ x}I+Iggi
return pageSize; J$w<$5UY
} C]`$AqKl
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publicvoid setPageSize(int pageSize){ z3m85F%dR
this.pageSize = pageSize; WUXx;9 >
} o&)8o5
Z4w!p?Wqa
publicint getTotalCount(){ 6@F9G4<Z
return totalCount; sW'AjI
} dhf!o0'1M
u5b|#&-mX
publicvoid setTotalCount(int totalCount){ Y>dzR)~3[
if(totalCount > 0){ W ]?G}Q;
this.totalCount = totalCount; X Dm[Gc>(~
int count = totalCount / /cQueUME`
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pageSize; ND#Yenye
if(totalCount % pageSize > 0) -[9JJ/7y
count++; 1POmP&fI(
indexes = newint[count]; }"P|`"WW
for(int i = 0; i < count; i++){ b)5uf'?-
indexes = pageSize * Ru!iR#s)!
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i; eFTpnG
} g<;q.ZylT
}else{ ?*1uN=oI{*
this.totalCount = 0; o!Ieb
} ;yLu R
} l<LP&
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publicint[] getIndexes(){ :vqgGKml$
return indexes; bL+_j}{:N
} RSyUaA
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publicvoid setIndexes(int[] indexes){ mCsMqDH
this.indexes = indexes; O1U= X:Zl
} F Q7T'G![
< #}5IQ5`Z
publicint getStartIndex(){ Q4!_>YZ
return startIndex; =9boya,>
} aFb==73aLw
.B]MpmpK
publicvoid setStartIndex(int startIndex){ IS{wtuA.
if(totalCount <= 0) pnowy;
this.startIndex = 0; #@9/g
elseif(startIndex >= totalCount) *K6g\f]b #
this.startIndex = indexes FaQe_;
L~rBAIdD
[indexes.length - 1]; vrhT<+q
elseif(startIndex < 0) +_?hK{Ib"
this.startIndex = 0; 8:c-k|CX
else{ ]}-7_n#cC
this.startIndex = indexes rq/yD,I,
r6MMCJ|G
[startIndex / pageSize]; ;4^Rx
} kHghPn?8]
} 2G67NC?+
RXpw!
publicint getNextIndex(){ rb2S7k0{
int nextIndex = getStartIndex() + Jr
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pageSize; 0d"[l@UU0
if(nextIndex >= totalCount) 7$vYo
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return getStartIndex(); \FbvHr,
else ?qLFaFt/
return nextIndex; Yq0| J
} *8yAG]z
jk; clwyz/
publicint getPreviousIndex(){ +,TRfP
Fb
int previousIndex = getStartIndex() - 85 |OGtt
nJG U-Z
pageSize; b9KP( _
if(previousIndex < 0) HZzD VCU
return0; G_3O]BMKd)
else iZ3IdiZ
return previousIndex; /7nb,!~~l
} G~^r)fm_
fo*2:?K&
} H1pO!>M
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抽象业务类 c)TPM/>(p
java代码: *v
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/** =w_Ype`
* Created on 2005-7-12 RE7?KR>
*/ t9k zw*U9
package com.javaeye.common.business; $k@O`xD,q
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import java.io.Serializable; W+aP}rZm:
import java.util.List; 67JA=,EE
fnjPSts0
import org.hibernate.Criteria; F 5bj=mI
import org.hibernate.HibernateException; n71r_S*
import org.hibernate.Session; 6@h/*WElG
import org.hibernate.criterion.DetachedCriteria; \%JgH=@
:=
import org.hibernate.criterion.Projections; M)J5;^["
import NR5gj-B[
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org.springframework.orm.hibernate3.HibernateCallback; 1y4|{7bb
import }WC[$Y_@
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org.springframework.orm.hibernate3.support.HibernateDaoS KVoS
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upport; sQUM~HD\a
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import com.javaeye.common.util.PaginationSupport; {nBhdM :i
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public abstract class AbstractManager extends tzWSA-Li
.;y.]Z/;
HibernateDaoSupport { Z,
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privateboolean cacheQueries = false; Q04al=
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privateString queryCacheRegion; qTRsZz@
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publicvoid setCacheQueries(boolean .KB^3pOpx
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cacheQueries){ [`#CXq'
this.cacheQueries = cacheQueries; @wGPqg
} SB;&GHq"n
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publicvoid setQueryCacheRegion(String !fV+z%:
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queryCacheRegion){ j"t(0m
this.queryCacheRegion = WrnrFz
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queryCacheRegion; .wEd"A&j
} *<$*"p
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publicvoid save(finalObject entity){ i^/T
getHibernateTemplate().save(entity); bQzZy5,
} 1jmjg~W
JK7G/]j+Ez
publicvoid persist(finalObject entity){ EKYY6S2
getHibernateTemplate().save(entity); P>y@kPi
} WA<v9#m
5N#aXG^9
publicvoid update(finalObject entity){ A]_7}<<N
getHibernateTemplate().update(entity); pQyK={7?`
} 2jA {SY-
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publicvoid delete(finalObject entity){ >2Y=*K,:
getHibernateTemplate().delete(entity); ]{;gw<T
} ^rB8? kt
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publicObject load(finalClass entity, 6B8VfQ9[
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finalSerializable id){ =Pyj%4Rs
return getHibernateTemplate().load $f$SNx)),
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(entity, id); n QF(vTDN
} lne|5{h
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publicObject get(finalClass entity, CQc+#nRe
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finalSerializable id){ @JiLgIe`
return getHibernateTemplate().get 0.Q
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(entity, id); pN,u`[
} +N]J5Ve-`t
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publicList findAll(finalClass entity){ k`cfG\;r
return getHibernateTemplate().find("from ^L,K& Jd
^7`BP%6
" + entity.getName()); OW&!at
} ~V:\ _{mE
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publicList findByNamedQuery(finalString IY1//9
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namedQuery){ :^<3>zk
return getHibernateTemplate "-E\[@/
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().findByNamedQuery(namedQuery); b.OsiT;_j
} !K#qe Y}
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publicList findByNamedQuery(finalString query, p
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finalObject parameter){ lPe&h]@ >
return getHibernateTemplate JB\UKZXw
p0]=QH
().findByNamedQuery(query, parameter); mwO6g~@`
} ^23~ZHu
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publicList findByNamedQuery(finalString query, I<DL=V
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finalObject[] parameters){ b8H{8{wi|
return getHibernateTemplate YByLoM*
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().findByNamedQuery(query, parameters); V~qNyOtA]
} ~\r*
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publicList find(finalString query){ TbMW|0 #w
return getHibernateTemplate().find \a<wKTkn
hy9\57_#
(query); AI2~Jp
} [=C6U_vU
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publicList find(finalString query, finalObject )J=! L\
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parameter){ ^ G]J ,+
return getHibernateTemplate().find -$\y_?}
}YQX~="
(query, parameter); Xa[.3=bV?
} aI'&O^w+
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public PaginationSupport findPageByCriteria A]*}HZ,
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(final DetachedCriteria detachedCriteria){ )w em|:H
return findPageByCriteria zE*li`@
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); JhYe6y[q
} Z<oaK
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public PaginationSupport findPageByCriteria MyOd,vU
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(final DetachedCriteria detachedCriteria, finalint Nd4f^Y
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startIndex){ 4>YR{
return findPageByCriteria ]U?^hZ_
<(#(hDwy
(detachedCriteria, PaginationSupport.PAGESIZE, qyb?49I
t[HE6ea
startIndex); VD AaYDi
} "37lx;CH
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public PaginationSupport findPageByCriteria /*~EO{o
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(final DetachedCriteria detachedCriteria, finalint D'>_I.
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pageSize, H.P_]3f
finalint startIndex){ Xc++b|k
return(PaginationSupport) #&+{mCjs
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getHibernateTemplate().execute(new HibernateCallback(){ yNBQGSH
publicObject doInHibernate i%iL[id:w
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(Session session)throws HibernateException {
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Criteria criteria = q~Hn-5H4Q
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detachedCriteria.getExecutableCriteria(session); 8qoMo7-f
int totalCount = Gf6p'(\zun
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((Integer) criteria.setProjection(Projections.rowCount Ha#=(9.
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()).uniqueResult()).intValue(); ejKucEgD
criteria.setProjection F~ty!(c
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(null); &$BjV{,/zc
List items = 1y&\5kB
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criteria.setFirstResult(startIndex).setMaxResults e)IzQ7Zex
+.8
\p5
(pageSize).list(); rw[ph[\X
PaginationSupport ps = d7^}tM
yZ7&b&2nLn
new PaginationSupport(items, totalCount, pageSize, (y'hyJo
zC:ASt
startIndex); b)#hSjWO#
return ps; OG~gFZr)6
} n)/z0n!\
}, true); ZmqKQO
} &<g|gsG`
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public List findAllByCriteria(final Oxnp0 s
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DetachedCriteria detachedCriteria){ ;<Sd~M4f
return(List) getHibernateTemplate =[ 46`-_
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().execute(new HibernateCallback(){ L&8~f]
publicObject doInHibernate T.F!+
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(Session session)throws HibernateException { OnziG+ak
Criteria criteria = 0JS?; fk
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detachedCriteria.getExecutableCriteria(session); OKZV{Gja
return criteria.list(); g'f@H-KCD
} Xq4O@V
}, true); fb7; |LF
} ;V_e>TyG
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public int getCountByCriteria(final H'5)UX@LP
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DetachedCriteria detachedCriteria){ ?,Xw[pR
Integer count = (Integer) je-!4r,
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getHibernateTemplate().execute(new HibernateCallback(){ B
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publicObject doInHibernate + 480 l}
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(Session session)throws HibernateException { M^Yh|%M
Criteria criteria = ja'T+!k
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detachedCriteria.getExecutableCriteria(session); Po;W'7"Po`
return "Y.tht H
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criteria.setProjection(Projections.rowCount Kn{4;Xk\
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<J
()).uniqueResult(); \\ij(>CI
} :G=fl)!fE
}, true); Ny7 S
return count.intValue(); 5I;&mW`1,`
} "cGk)s
} 2nObl'ec
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wm@@$
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用户在web层构造查询条件detachedCriteria,和可选的 +E+p"7
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 E~T-=ocKE
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PaginationSupport的实例ps。 'BxX0
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ps.getItems()得到已分页好的结果集 zk+9'r`-D
ps.getIndexes()得到分页索引的数组 }tuC}
ps.getTotalCount()得到总结果数 xa*hi87L*
ps.getStartIndex()当前分页索引 {WS;dX4
ps.getNextIndex()下一页索引 uMv,zO5
ps.getPreviousIndex()上一页索引 2'Uu:Y^
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Zl!kJ:0
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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
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一下代码重构了。 Lb-OsKU
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我把原本我的做法也提供出来供大家讨论吧: G4;Oi=
ty!`T+3
首先,为了实现分页查询,我封装了一个Page类: Qel9G($=
java代码: hZ,_6mNg
I
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/*Created on 2005-4-14*/ 2[yd> (`
package org.flyware.util.page; t}4,]ms
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/** KF}hV9IU
* @author Joa C): 1?@
* Nx;~@
*/ ~8+ Zs
publicclass Page { 1GRCV8"Z^
>R_&Ouh:
/** imply if the page has previous page */ J)>c9w
privateboolean hasPrePage; _LnpnL:
u#~RkY7s
/** imply if the page has next page */ ; 2#y7!
privateboolean hasNextPage; Tidn-2L73O
({_{\9O,3
/** the number of every page */ FV!q!D
privateint everyPage; f~[7t:WD*
cjY-y-vO
/** the total page number */ ~?}Emn;t
privateint totalPage; .P]+? %&
;'K5J9k
/** the number of current page */ N+xP26D8
privateint currentPage; !.gIHY
CRE3icXbQ
/** the begin index of the records by the current BWrxunHO
BU_nh+dF
query */ tk`v:t!6U
privateint beginIndex; ND;#7/$>
%> eiAB_b
2zb"MEOS5
/** The default constructor */ j^JPZ{ej?
public Page(){ "^-a M
WT=;: j
} ~!L}yw
4VSU8tK|N]
/** construct the page by everyPage Sm|6 %3
* @param everyPage AkV#J,
3LC
* */ eMsd37J
public Page(int everyPage){ CTa57R
this.everyPage = everyPage; q} >%8;nm
} O>,e~#!
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/** The whole constructor */ yf+)6D -9n
public Page(boolean hasPrePage, boolean hasNextPage, abj Q)=u
EQM{
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int everyPage, int totalPage, i.m^/0!
int currentPage, int beginIndex){ 5;EvNu
this.hasPrePage = hasPrePage; L4HI0Mx
this.hasNextPage = hasNextPage; /4Gt{ygSr
this.everyPage = everyPage; jLluj
this.totalPage = totalPage; ~>|ziHx
this.currentPage = currentPage; i/4>2y9/F4
this.beginIndex = beginIndex; :o3N;*o>)0
} L0o\J` :
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/** 1+s;FJ2}
* @return ms]sD3z/W+
* Returns the beginIndex. =^?/+p8k
*/ KWHY4
publicint getBeginIndex(){ g7H(PF?
return beginIndex; 2+XAX:YD
} WyiQoN'q
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/** 9*M,R,y
* @param beginIndex @yYkti;4-
* The beginIndex to set. F^:3?JA_
*/ t6c4+D'{].
publicvoid setBeginIndex(int beginIndex){ gbA_DZ
this.beginIndex = beginIndex; B+`g>h
} C U0YIL
ob]w;"
/** W>r+h-kR
* @return
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* Returns the currentPage. RA 6w}:sq7
*/ 9(Xn>G'iT
publicint getCurrentPage(){ ?r4>" [
return currentPage; =3P)q"
} %|oym.-I6
At;LO9T3z
/** h?U
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* @param currentPage i%?* @uj
* The currentPage to set. *;FdD{+
*/ }GM'.yutX
publicvoid setCurrentPage(int currentPage){ ]SEZaT
this.currentPage = currentPage; -9?]IIVb
} vY3h3o
x8|J-8A(
/** X?Q4} Y
* @return %BODkc Zh
* Returns the everyPage. !4!~Lk=
*/ h68 xet;
publicint getEveryPage(){ Y]a@j!
return everyPage; lB4WKn=?Kl
} ['D]>Ot68
l]SX@zTb
/** z$sGv19pB
* @param everyPage K
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* The everyPage to set. #-J>NWdt
*/ fP1!)po
publicvoid setEveryPage(int everyPage){ e3\T)x&=
this.everyPage = everyPage; !,PWb3S
} j>kqz>3
`]aeI'[}R
/** rm_Nn8p,
* @return @4#vm@Yf_
* Returns the hasNextPage. 7zc^!LrW<
*/ D%Z|
publicboolean getHasNextPage(){ W+*
V)tf
return hasNextPage; ?JUeuNs9
} O6Y0XL
j<$2hiI/?&
/** l,).p
* @param hasNextPage HaYo!.(Fv
* The hasNextPage to set. ;*J
*/ /L3:
publicvoid setHasNextPage(boolean hasNextPage){ B5QFK
this.hasNextPage = hasNextPage; 5V-I1B&
} 7:@'B|
AXB7oV,xt
/** Ys7]B9/1O
* @return y{Q
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* Returns the hasPrePage. I1J-)R+
*/ AZ<=o
publicboolean getHasPrePage(){ =~gvZV-<
return hasPrePage; 9YGY,sx
} JXxwr)i
Xa&kIq}(g
/** qP
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* @param hasPrePage '%;m?t%q
* The hasPrePage to set. jiGTA:v
*/ - YBY[%jF>
publicvoid setHasPrePage(boolean hasPrePage){ 1;iUWU1@
this.hasPrePage = hasPrePage; $~kA
B8z
} A%vbhD2;W
{`_i`
/** +T+#q@
* @return Returns the totalPage. "M0z(NkH
* qgB_=Q#E
*/ @F>D+=hS
publicint getTotalPage(){ [>9is=>o.
return totalPage; >mkFV@`
} jWgX_//!
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/** +|f@^-
* @param totalPage YYS0`
* The totalPage to set. O0:q;<>z
*/ 8CE = 4
publicvoid setTotalPage(int totalPage){ iRBfx
this.totalPage = totalPage; +,l-Nz
} 'fW-Y!k%
L50n8s
} wM{s|Ay
{h4E8.E
tX[WH\(xI
bd`P0f?
F[MFx^sT{
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 MfkZ
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个PageUtil,负责对Page对象进行构造: u:b=\T L
java代码: p}P-6&k,U
#z42C?V
cb bFw
/*Created on 2005-4-14*/ c " ,*h
package org.flyware.util.page; yQrD9*t&g
/@5YW"1
import org.apache.commons.logging.Log; Zd&S@Z
import org.apache.commons.logging.LogFactory; /Kbl%u
R#KU^]"(
/** $Q0n
* @author Joa *ui</+
* 92{\B-
l
*/ -qoH,4w
publicclass PageUtil { =c7;r]Ol
]^]wP]R_
privatestaticfinal Log logger = LogFactory.getLog 9u:Q,0\
2rMpgV5
(PageUtil.class); N21smC}
;}t(Wnu.
/** K^[?O{x^B
* Use the origin page to create a new page Ho%CDz
z
* @param page Gh$^ {
* @param totalRecords I:.s_8mH}
* @return M3AXe]<eC1
*/ Pc9H0\+Xk
publicstatic Page createPage(Page page, int v0y(58Rz.
0IpmRH/
totalRecords){ /tLVX} &
return createPage(page.getEveryPage(), ;rS{:
KlqY@Xt
page.getCurrentPage(), totalRecords); Js;h%
} hOeRd#AQK
pJ{Y
lS{
/** < vP=zk
* the basic page utils not including exception ?#fQ~ s
.^g p?
handler 'PHl$f*k
* @param everyPage +h$
9\
* @param currentPage cnLro
* @param totalRecords
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* @return page KTv$
*/ -YE^zzh
publicstatic Page createPage(int everyPage, int ##{taR8
DI%saw
currentPage, int totalRecords){ r/1(]#kOX
everyPage = getEveryPage(everyPage); [
3HfQ
currentPage = getCurrentPage(currentPage); ctUp=po
int beginIndex = getBeginIndex(everyPage, yHGADH0B
Z]ONh
currentPage); 9B4&m|g
int totalPage = getTotalPage(everyPage, 9VT;ep
He)%S]RLk
totalRecords); cu6Opq9
boolean hasNextPage = hasNextPage(currentPage, UI#h&j5pW
ww/Uzv
totalPage); =#\:}@J5I
boolean hasPrePage = hasPrePage(currentPage); If.r5z9
Q20%"&Xp]
returnnew Page(hasPrePage, hasNextPage, h\e.e3/
everyPage, totalPage, Y0>y8UV
currentPage, Z}QB.$&
% `3jL7|
beginIndex); xfQ1T)F3g
} [vgtc.V
wj+*E6o-n
privatestaticint getEveryPage(int everyPage){ ,s(,S
return everyPage == 0 ? 10 : everyPage; VE24ToI?W"
} MPV5P^@X
g'gdgfvn
privatestaticint getCurrentPage(int currentPage){ PM+[,H
return currentPage == 0 ? 1 : currentPage; ys~x$
} 40/Y\
1qch]1
^G
privatestaticint getBeginIndex(int everyPage, int ,)XLq8
;fJ.8C
currentPage){ yw!{MO
return(currentPage - 1) * everyPage; xUvs:
} Zh,71Umz
,^:.dFH6
privatestaticint getTotalPage(int everyPage, int [~^0gAlQC
<!+Az,-
totalRecords){ T|p"0b A
int totalPage = 0; yLGRi^d#
N$DkX)Z
if(totalRecords % everyPage == 0) *Uh!>Iv;
totalPage = totalRecords / everyPage; RpK@?[4s
else g*Phv|kI
totalPage = totalRecords / everyPage + 1 ; '7/)Ot(
B6"0OIDY"
return totalPage; _+,TT['57s
} gSgr6TH0
Gq6*SaTk
privatestaticboolean hasPrePage(int currentPage){ <UI
[%yXj
return currentPage == 1 ? false : true; <[phnU^
8
} s S
Mh`4'
(ZGbhMK
privatestaticboolean hasNextPage(int currentPage,
<Uur^uB
]yu:i-SfP
int totalPage){ d1*<Ll9K
return currentPage == totalPage || totalPage == C}X\|J
XuTD\g3)
0 ? false : true; m[$_7a5
} -} +[
lk!@?
%)|s1B'd
} omFz@
H.;Q+A,8^
pw#-_
@L`jk+Y0vF
>sF)BoLc
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。 4
:v=pZ
edD)TpmE,
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 (BM47D=v
bLL2
做法如下: HsWk*L `y
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 QWU[@2@%r
$:6!H:ty
的信息,和一个结果集List: u?"Vm
java代码: 1cDF!X]
.X&9Q9T=#
Kq!3wb;
/*Created on 2005-6-13*/ 0"R|..l/
package com.adt.bo; z{543~Og59
IgzQr >
import java.util.List; YR70BOxK
Smh,zCc>s
import org.flyware.util.page.Page; vI?, 47Hj+
[7-?7mp!B
/** h;Qk@F
* @author Joa sT.ss$HY9,
*/ TvM~y\s
publicclass Result { zCA2X
!7F
[Pp'Ye~K@c
private Page page; J4'eI[73
h(4v8ae
private List content; "MsIjSu
/1 dT+>
/** ?0.NIu,,o
* The default constructor YUb_y^B^
*/ Y2TtY;
public Result(){ {:s f7
super(); ZcsZ$qt^
} Ef\-VKh
z}<^jgJ
/** #tHK"20
* The constructor using fields =I<R! ZSN
* OI*H,Z"
* @param page 1 zZlC#V
* @param content |)&%A%m
*/ 0b>h$OU/
public Result(Page page, List content){ gR**@t=;j
this.page = page; DXo|.!P=3
this.content = content; #E?4E1bnB
} J,hCvm
mw!F{pw
/** PCvWS.{
* @return Returns the content. !if
*/ <%d>v-=B
publicList getContent(){ b}f~il
return content; SBpL6~NW
} \zY!qpX<
|4JEU3\$
/** 45e~6",
* @return Returns the page. sB</DS
*/ XSDpRo
public Page getPage(){ '%qr.T
%
return page; Ri{=]$
} oRFq@g
|>Vb9:q9Po
/** ok[i<zl;'
* @param content ixFi{_
* The content to set. d$RIS+V
*/ #R"*c
hLV
public void setContent(List content){ b-DvW4B
this.content = content; -~0^P,yQ
} F847pyOJnf
h\o.&6sd
/** )UR7i8]!0
* @param page QY/w
* The page to set. zdYjF|
*/ r"
y.KD^
publicvoid setPage(Page page){ 2:kH[#
this.page = page; Ie_wHcM<
} .3;;;K9a~]
} uph(V
*T/']t
Wc#24:OKe3
+2{Lh7Ks
6t$8M[0-U
2. 编写业务逻辑接口,并实现它(UserManager, khe}*y
u[YGm:}
UserManagerImpl) L_T5nD^D
java代码:
)2.Si#
UfGkTwoo=
29KiuP
/*Created on 2005-7-15*/ XwmL.Gg:]7
package com.adt.service; [~HN<>L@C
W4S,6(
import net.sf.hibernate.HibernateException; XTyxr
Ytkv!]"
import org.flyware.util.page.Page; k:;r2f
\dVOwr
import com.adt.bo.Result; Sc0w.5m6
(HVGlw'`
/** X8|,
* @author Joa DVA:Cmh\
*/ :>
'+"M2r
publicinterface UserManager { ;I}fBZ3
$i&zex{\
public Result listUser(Page page)throws CZ;6@{ o
)e{aN+
HibernateException; L,\Iasv
w<#!h6Y=
} f#;> g
@C$]//;
'DR!9De
*w&e\i|7
K0~rN.C!0
java代码: TbU#96"~.
TH;hO).u
8tL~FiHb"
/*Created on 2005-7-15*/ KO [Yi
package com.adt.service.impl; .A|udZ,
9;{CIMg&
import java.util.List; 6Mf0`K
)7F/O3Tq
import net.sf.hibernate.HibernateException; %J(:ADu]
e6*8K@LHB
import org.flyware.util.page.Page; G{}VPcrbC
import org.flyware.util.page.PageUtil; 0J9x9j`&j
Ui~>SN>s
import com.adt.bo.Result; XS#Qu=,-
import com.adt.dao.UserDAO; Cdn J&N{
import com.adt.exception.ObjectNotFoundException; 0mE 0 j
import com.adt.service.UserManager; 4(+PD&_J
%b$>qW\*&
/** _6Sp QW
* @author Joa B\~}3!j
*/ oJ^P(] dw
publicclass UserManagerImpl implements UserManager { 9[4xFE?|
Wr
4,YQM
private UserDAO userDAO; /^ts9:
7!1S)dup
/** (PLUFT
* @param userDAO The userDAO to set. oH@78D0A
*/ Q &8-\
publicvoid setUserDAO(UserDAO userDAO){ @ArSC
this.userDAO = userDAO; *dQSw)R
} G|Ti4_w
3";q[&F9y
/* (non-Javadoc) =_CzH(=f#
* @see com.adt.service.UserManager#listUser x}4q {P5$
&>O+}>lr9
(org.flyware.util.page.Page) vM={V$D&
*/ [^iN}Lz
public Result listUser(Page page)throws j 7B!h|
0GwR~Z}Z
HibernateException, ObjectNotFoundException { &=[WIG+rk
int totalRecords = userDAO.getUserCount(); 0GL M(JmK
if(totalRecords == 0) 0-gAyiKx?
throw new ObjectNotFoundException PCA4k.,T
q.vIc
?a
("userNotExist"); Wwo0%<2y
page = PageUtil.createPage(page, totalRecords); R2NZ{"h
List users = userDAO.getUserByPage(page); 6]N.%Y[(
returnnew Result(page, users); ;uW FHc5@B
} ib m4fa
pH;%ELZ
} %b0*H_ok7
Jm@oDME_E
7<4qQ.deE
Om&Dw|xG8
~DWl s.
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 vO=fP_
cQ|NJ_F{1
询,接下来编写UserDAO的代码: XppOU
3. UserDAO 和 UserDAOImpl: qs6aB0ln
java代码: f$( e\++
\vNU,WO
buC{r,
/*Created on 2005-7-15*/ $b\P|#A
package com.adt.dao; x-c"%Z|
M|-)GvR$J
import java.util.List; Bvj0^fSm
=N@t'fOr
import org.flyware.util.page.Page; ?2a $*(
1YA% -~
import net.sf.hibernate.HibernateException; [aS*%Heu
5;?yCWc
/** $]1=\I
* @author Joa <3iMRe
*/ zDp 2g)
publicinterface UserDAO extends BaseDAO { oU|c.mYe
mOSv9w#,
publicList getUserByName(String name)throws 9L9sqZUB
|{;G2G1[
HibernateException; t)
+310w
NI5``BwpO
publicint getUserCount()throws HibernateException; zi:BF60]=
<#.g=ay
publicList getUserByPage(Page page)throws b-y
wBzC5T%,
HibernateException; u-TUuP
,Q,^3*HX9}
} H]!"Zq k
\jA~9
P2!C|SLK
tgaO!{9I?
|o@%dH
java代码: +V+a4lU14
% nIf)/2g
5IN(|B0
/*Created on 2005-7-15*/
5uf a
package com.adt.dao.impl; 8Y3I0S
h~26WLf.
import java.util.List; eFAnFJ][L
7.T?#;'3
import org.flyware.util.page.Page; 9kojLqCT
KG@8RtHsQ
import net.sf.hibernate.HibernateException; .2pK.$.
import net.sf.hibernate.Query; z=FZiH
!c-*O<Y
import com.adt.dao.UserDAO; P$sxr
@KA4N`
/** IAEAhqp
* @author Joa nie% eC&U
*/ Wf<LR3
public class UserDAOImpl extends BaseDAOHibernateImpl I|J/F}@p
>MK98(F
implements UserDAO { a>)f=uS
Q^I\cAIB
/* (non-Javadoc) TKjFp%
* @see com.adt.dao.UserDAO#getUserByName V,9cl,z+
{^'HL
(java.lang.String) J=L5=G7(
*/ 0Qd:`HF[
publicList getUserByName(String name)throws T Ge_G_'o
^J d
r>@
HibernateException { v@Ox:wl>
String querySentence = "FROM user in class '2O\_Uz
d\Zng!Z '
com.adt.po.User WHERE user.name=:name"; vI]N^j2%
Query query = getSession().createQuery 8X0z~&
(ik\|y% A
(querySentence); 6^Sa;
query.setParameter("name", name); Kg$Mx
return query.list(); XUw/2"D'?
} L+QLLcS~EM
ipILG4
/* (non-Javadoc) j.kG};f
* @see com.adt.dao.UserDAO#getUserCount() VD :/PL
*/ JLi|Td"1%
publicint getUserCount()throws HibernateException { _2nx^E(pd
int count = 0; ;>YzEo
String querySentence = "SELECT count(*) FROM ]_f<kW\1*
\L\b $4$d
user in class com.adt.po.User";
Z<phcqEi8
Query query = getSession().createQuery 9,tej
[9 RR8
(querySentence); _y>~
yZx
count = ((Integer)query.iterate().next "vslZ`RU
%#}Z y
()).intValue(); rD>f|kA?L
return count; hL5|69E
} +]50D xflA
Yuc> fFA
/* (non-Javadoc) V!dtF,tH
* @see com.adt.dao.UserDAO#getUserByPage TU7'J
rt|7h>RQ
(org.flyware.util.page.Page) ^KELKv,_
*/ &w~d_</
publicList getUserByPage(Page page)throws z~Q>V]a>;
9M9?%N:ra
HibernateException { F:l%O#V
String querySentence = "FROM user in class MxGW(p
ym6K!i]q4
com.adt.po.User"; 7`YEH2
Query query = getSession().createQuery !L8#@BjU
!3v1bGk
(querySentence); )tpL#J
query.setFirstResult(page.getBeginIndex()) PY0j9$i?
.setMaxResults(page.getEveryPage()); O<e{
return query.list(); (3&?w y_l
} *|E[L^
Ib0ZjX6
} GDy9qUV
4NIRmDEd
i2^>vYCsl
{91nL'-'
kE(mVyLQ
至此,一个完整的分页程序完成。前台的只需要调用 0<B$#8
tdaL/rRe
userManager.listUser(page)即可得到一个Page对象和结果集对象 BV+ Bk+
gRT00
的综合体,而传入的参数page对象则可以由前台传入,如果用 8'r[te4,
PJ'E/C)i
webwork,甚至可以直接在配置文件中指定。 CsifKHI
AnvRxb.e
下面给出一个webwork调用示例: lUiL\~Gq
java代码: PAOJ\U
O<;3M'y\
9RI-Lq`
/*Created on 2005-6-17*/ m<g~H4
package com.adt.action.user; {$Gd2gO
c:u5\&~{
import java.util.List; mo#04;VF
2Q"K8=s
import org.apache.commons.logging.Log; wIBO
^w\J
import org.apache.commons.logging.LogFactory; g
SAt@2*U2
import org.flyware.util.page.Page; b,%C{mC
dmN&+t
import com.adt.bo.Result; [,KXze_m
import com.adt.service.UserService; oFGhNk
import com.opensymphony.xwork.Action; XNu^`Ha
D+7Rz_=
/** LAe6`foW/
* @author Joa pQ<Y:-`c
*/ H&}pkrH~
publicclass ListUser implementsAction{ VgC2+APg
+V^;.P</
privatestaticfinal Log logger = LogFactory.getLog oD1/{dRzj
1\rz%E
(ListUser.class); _M5|Y@XN-
3K/MvNI>
private UserService userService; B i<Q=x'Z;
Q7COQ2~K
private Page page;
H =^`!
Sw^u3
privateList users; ~PahoRS
\qK&q
/* SrK<fAkx
* (non-Javadoc) -n<pPau2
* Y~E`9
* @see com.opensymphony.xwork.Action#execute() x`IEU*z#
*/ %O;bAC_M
publicString execute()throwsException{ n`&U~s8w
Result result = userService.listUser(page); x6ARzH\
page = result.getPage(); JNUt$h
users = result.getContent(); 0f>5(ek
return SUCCESS; }HePZ{PLM
} +|89>}w4
P &e\)Z|
/** 6,9>g0y'NG
* @return Returns the page. D^3vr2
*/ U,- 39mr
public Page getPage(){ h"lv7;B$
return page; Ev(>z-{F
} 'B0{_RaTb
Gvqxi|
/** {"QNJq#:
* @return Returns the users. FfPar:PHj
*/ =k0_eX0
publicList getUsers(){ p\ZNy\N^
return users; //<nr\oP
} r_6ZO&
iBgx
/** YCM]VDx4u1
* @param page Z>W g*sZy)
* The page to set. ApV~(k)W
*/ Pjjewy1}^
publicvoid setPage(Page page){ 5VAK:eB
this.page = page; \(Y\|zC'0$
} mFaZio0GK
MgrLSKLT
/** /M4{Wc
* @param users O7<]U_"I
* The users to set. .1Al<OLL
*/ [t@Mn
publicvoid setUsers(List users){ &wCg\j_c
this.users = users; lqZ 5?BD1
} j<@lX^
s`'{I8'p/
/** ?Yk.$90
* @param userService ?ztkE62t
* The userService to set. j=aI9p
*/ JYd 'Jp8bP
publicvoid setUserService(UserService userService){ 8UyMVY
this.userService = userService; (ECnMti+
} 8a'.ZdqC?
} ~SF<,-Kg
]d0tE?9
A
'5,LfTu
Dq5j1m.
OFv%B/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, tlqiXh<
DSk/q-'u
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 YSh+pr
E}p&2P+MR
么只需要: Hx*;jpy(2
java代码: K]0:?h;%Ld
)oPLl|=h
JB`\G=PiL
<?xml version="1.0"?> O_DtvjI'
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork X{'q24\F
\cUNsB5
1.0//EN" "http://www.opensymphony.com/xwork/xwork- $[&*Bj11Yg
7~aM=8r
1.0.dtd"> 80/F7 q'tn
.#Z%1U%P.
<xwork> 6qaQ[XTxf
x`mN U
<package name="user" extends="webwork- {{MRELipW
9Hu/u=vB<
interceptors"> JSW}*HR
X+}1
<!-- The default interceptor stack name "4H
+!r}
^Z#W_R\l
--> mfo1+owT
<default-interceptor-ref %S nd\
hn=[1<#^(
name="myDefaultWebStack"/> 5v}8org
Vq;A>
<action name="listUser" ?yR&/a
&n?^$LTPY
class="com.adt.action.user.ListUser"> 9;Ox;;w
<param q+]h=:5=I
^(h+URFpA
name="page.everyPage">10</param> I*kK 82
<result %r6y
;vAf
g(J&m<I
name="success">/user/user_list.jsp</result> rJ{O(n]j
</action> fCtPu08{Z
+0q>fp_K(+
</package> *nsAgGKKM^
e9[|!/./5
</xwork> QC;^xG+W
G\r?f&
#x3ujJ
fUQ6Z,9
$K'|0
q]N:Tpm9
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 .?e\I`Kk^'
I=9!Rs(QF
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。 qfz 8jY]
c#]q^L\x
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 H;fxxu`cS
z0*_^MH
}HYjA4o\A
Xo*%/0q'
dwd:6.J(
我写的一个用于分页的类,用了泛型了,hoho P*Tx14xe4
7C2&NyWJ
java代码: CL}{mEr}
(B-43!C
`8>Py~
package com.intokr.util;
9*=W- v
e|D;OM
import java.util.List; /<8N\_wh
nn9wdt@.]
/** `o?Ph&p}
* 用于分页的类<br> D<X.\})Md
* 可以用于传递查询的结果也可以用于传送查询的参数<br>
\$OF1i@
* @b~fIW_3>
* @version 0.01 BC;:
* @author cheng ,b;{emX h
*/ _#}n~}d
public class Paginator<E> { PF7&p~O(Z
privateint count = 0; // 总记录数 JA_BKA
privateint p = 1; // 页编号 4bJZmUb
privateint num = 20; // 每页的记录数 Mz;[ +p
privateList<E> results = null; // 结果 xOHgp=#D
[mr9(m[F
/** m7GR[MR
* 结果总数 u=/CRjot
*/ pOkLb
#
publicint getCount(){ JiU9CeD3
return count; ?8mlZ
X9C
} U}l14
zf>5,k'x'A
publicvoid setCount(int count){ FwZ>{~?3
this.count = count; U(;&(W"M
} "y<?Q}1
dN}#2Bo=
/** t"YNgC ^
* 本结果所在的页码,从1开始 g@Qgxsyk>
* Pv+5K*"7Cg
* @return Returns the pageNo. 1G'`2ATF*
*/ @b3#X@e}
publicint getP(){ {Pu\?Cq
return p; ~|AwN [
} UD y(v ]
?kz+R'
/** nbTVU+
* if(p<=0) p=1 z]bwnJfd
* a`u
S[r>
* @param p k%op>
&
*/ 1I}b|6
`
publicvoid setP(int p){ vHE^"l5 v
if(p <= 0) K!mOr
p = 1; b]JI@=s?
this.p = p; J!*/a'Cv
} 'XUKN/.
7RvUH-S[
/** &X]\)`j0
* 每页记录数量 2. X" f
*/ X5*C+ I=2
publicint getNum(){ ow' lRHZ
return num; ez9k4IO
} rqlc2m,<-p
|uH%6&\
/** "uPy,<l
* if(num<1) num=1 TV}}dw
*/ h`}3h<
8
publicvoid setNum(int num){ <_./SC
if(num < 1) DBs*Fx[
num = 1; 1]T`n /d V
this.num = num; 2qO3XI
} {3Vk p5%l
U\?g*
/** g3%t8O/M
* 获得总页数 ro[Y-o5Q0
*/ kV Rn`n0
publicint getPageNum(){ /+3a n9h
return(count - 1) / num + 1; N6[i{;K@N{
} Gj /3kS~@
jUqy8q&
/** 6dEyv99
* 获得本页的开始编号,为 (p-1)*num+1 M'1!<a-Mp
*/ S|GWcSg
publicint getStart(){ d'9:$!oz
return(p - 1) * num + 1; S2VVv$r_6
} (,xZGa
Sb:T*N0gS
/** s
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* @return Returns the results. qYp$fmj
*/ #m8sK(#lo
publicList<E> getResults(){ *V;3~x!
return results; 7>
Pgc
} :'r6TVDW
fH8!YQG8$
public void setResults(List<E> results){ ?&l)W~S
this.results = results; #rYENR[
} cub<G!K
G7* h{nE
public String toString(){ cUDg M
StringBuilder buff = new StringBuilder !@
YXZ
nD,{3B#
(); ;</Twm;:
buff.append("{"); (w2=
2$
buff.append("count:").append(count); '?Iif#Z1
buff.append(",p:").append(p); w9#R'
buff.append(",nump:").append(num); u:`y]
buff.append(",results:").append g3?U#7i
8Xm@r#Oy5
(results); s([Wn)I
buff.append("}"); <2P7utdZ
return buff.toString(); 0d\~"4 R
} QlW=_Ymv{
<kD#SV%"
} I/UQ' xx
y>(rZ^y&
RFG$X-.e