Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 9$B)hrJo
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 4<=eK7;XR
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 YHwVj?6W
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 &4ug3
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分页支持类: @LwVmR |{
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java代码: ~m,mvRS
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package com.javaeye.common.util; brpN>\
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import java.util.List; fzPgX
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publicclass PaginationSupport { 4nVO.Ud0$X
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publicfinalstaticint PAGESIZE = 30; ynOc~TN
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privateint pageSize = PAGESIZE; Z(Ls#hp
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privateList items; A61-AwvF8-
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privateint totalCount; ]9~#;M%1
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privateint[] indexes = newint[0]; U3VsMV*Y
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privateint startIndex = 0; 52q!zx E
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public PaginationSupport(List items, int BhhK| U/
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totalCount){ 37za^n?SG
setPageSize(PAGESIZE); e-T9HM&%P
setTotalCount(totalCount); plz=G}Y
setItems(items); :u|UVp5
setStartIndex(0); G41$oalQ1
}
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public PaginationSupport(List items, int '
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totalCount, int startIndex){ ;Vtpq3
setPageSize(PAGESIZE); }~0{1&
setTotalCount(totalCount); iaq:5||,
setItems(items); =,}!Ns{k
setStartIndex(startIndex); 6b1 Uj<
} 6`{)p&9
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public PaginationSupport(List items, int ~A{[=v
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totalCount, int pageSize, int startIndex){ _|2";.1E
setPageSize(pageSize);
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setTotalCount(totalCount); 7C6BZ$(
setItems(items); LnACce
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setStartIndex(startIndex); O'?lW~CD.>
} vA $BBXX
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publicList getItems(){ ,'@ISCK^
return items;
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} J1wGK|F~
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publicvoid setItems(List items){ ?(XX
this.items = items; `rFGSq$9
} 0Nzv@g{3
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publicint getPageSize(){ C'#)bX{
return pageSize; m_W.r+s~C4
} +R jD\6bJb
1 jd=R7
publicvoid setPageSize(int pageSize){ L
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this.pageSize = pageSize; T%xL=STJNy
} #hiDZ>nr
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g
publicint getTotalCount(){ 0hr)tYW,G
return totalCount; N1zrfn-VU
} D+nj[8y
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publicvoid setTotalCount(int totalCount){ :'Kx?Es
if(totalCount > 0){ s~'C'B?
this.totalCount = totalCount; Nd!=3W5?
int count = totalCount / [1X5r<(W5
))-M+CA
pageSize; n/|`Dz.
if(totalCount % pageSize > 0) /-9+(
count++; `'t;BXedz/
indexes = newint[count]; bGLp0\0[
for(int i = 0; i < count; i++){ ]t0S_UH$
indexes = pageSize * v[=E f
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i; !q1^X% a
} "uNxKLDB
}else{ M/I d\~
this.totalCount = 0; yM ~D.D3H
} Oc3%pb;
} > %*X2'^
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publicint[] getIndexes(){ YR`rg;n#
return indexes; z-E4-\a
} jCa;g{#@
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publicvoid setIndexes(int[] indexes){ q/G5aO*
this.indexes = indexes; U~c;W@T
} s$G8`$+i1
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publicint getStartIndex(){ f.CI.aozW
return startIndex; a-hGpYJJG
} t9l7
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publicvoid setStartIndex(int startIndex){ %P6!vx:&^b
if(totalCount <= 0) |}Lgo"cTC
this.startIndex = 0; ':dHYvP/UX
elseif(startIndex >= totalCount) eF\C?4
this.startIndex = indexes 00TdX|V`
`v
er "s;
[indexes.length - 1]; ^%^0x'"
elseif(startIndex < 0) ZJm^znpw6
this.startIndex = 0; xb;mm9H
else{ e@By@r&nql
this.startIndex = indexes 1i2O]e!
y?hW#l~#X
[startIndex / pageSize]; M] *pBc(o0
} Puh&F< B
} 4Fq}*QJ-
_
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publicint getNextIndex(){ *5)!y
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int nextIndex = getStartIndex() + %W+Fe,]
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pageSize; +.cv,1Vx
if(nextIndex >= totalCount) :Aw VeX@
return getStartIndex(); Y6a|\K|
else p-k qX
return nextIndex; >AJ|F)
} +3CMfYsr8
h='=uj8o5
publicint getPreviousIndex(){ ]={Hq9d@
int previousIndex = getStartIndex() - U4JN,`p{
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pageSize; kvn6
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if(previousIndex < 0) j C?
return0; Po3W+;@
else dPId=
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return previousIndex; 7O#>N}|
} jK53-tF~I
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} 7j8_O@_
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抽象业务类 $)!Z"2T
java代码: {'%=tJ[YX
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/** f`e.c_n(
* Created on 2005-7-12 |(5=4j]
*/ oLoa71Q}
package com.javaeye.common.business; g=Lt2UIJ
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import java.io.Serializable; al/~
import java.util.List; U' Cp3>
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import org.hibernate.Criteria; K9R[
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import org.hibernate.HibernateException; ln5On_Wm
import org.hibernate.Session; EZ4qhda
import org.hibernate.criterion.DetachedCriteria; 4)_ [)MZ\j
import org.hibernate.criterion.Projections; gQ~4udla.
import {+;8dtZ)x
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org.springframework.orm.hibernate3.HibernateCallback; kVY@q&p
import PLD!BD
n !QjptQ
org.springframework.orm.hibernate3.support.HibernateDaoS W3b\LnUa
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upport; 4.8,&{w<m
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import com.javaeye.common.util.PaginationSupport; %}/)_RzQ
(_* a4xGF
public abstract class AbstractManager extends kcle|B
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HibernateDaoSupport { @azS)4L
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privateboolean cacheQueries = false; ep5aBrN]"
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privateString queryCacheRegion; N`M5`=.
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publicvoid setCacheQueries(boolean 2.6,c$2tB
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cacheQueries){ -Je+7#P1
this.cacheQueries = cacheQueries; -Jhf]
} ;(XSw%Y
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publicvoid setQueryCacheRegion(String |:\h3M
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queryCacheRegion){ >,DR{A2hSB
this.queryCacheRegion = C oaqi`v4T
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queryCacheRegion; v#~,)-D&
} R{T4AZ@,'
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publicvoid save(finalObject entity){ \1tce`+
getHibernateTemplate().save(entity); I0Vm^\8
} j1BYSfX'
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publicvoid persist(finalObject entity){ uuq?0t2Z
getHibernateTemplate().save(entity); 3}"VUS0wh
} rTi.k
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publicvoid update(finalObject entity){ y"2c; *7[{
getHibernateTemplate().update(entity); MFC= oKD
} 9qw~]W~Nm
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publicvoid delete(finalObject entity){ }RD,JgmV
getHibernateTemplate().delete(entity); _8bqk\m+
} * 6uiOtH
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publicObject load(finalClass entity, C4b3ZcD2
~ WVrtY Ju
finalSerializable id){ y_\d[
return getHibernateTemplate().load sUg7
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(entity, id); g
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} towQoqv
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publicObject get(finalClass entity, OrzDr
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finalSerializable id){ ^.k}YSWut
return getHibernateTemplate().get Z{%h6""
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(entity, id); Lw3Z^G
} 6Z7{|B5}Y
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publicList findAll(finalClass entity){ S]k<Ixvf
return getHibernateTemplate().find("from M*%iMz
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" + entity.getName()); [IiwpC
} {"O'kx
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publicList findByNamedQuery(finalString d6wsT\S
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namedQuery){ |',MgA
return getHibernateTemplate y6;A4p>
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().findByNamedQuery(namedQuery); `NrxoU=
} !MoGdI-<r[
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publicList findByNamedQuery(finalString query, u PjJ>v
U ^[<G6<9]
finalObject parameter){ F?TAyD*
return getHibernateTemplate i{xgygp6f
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().findByNamedQuery(query, parameter); Hcuvu[)T"
} W$
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publicList findByNamedQuery(finalString query, v 6Tz7
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finalObject[] parameters){ ~`(#sjr6KR
return getHibernateTemplate ^lf{IM-Y
+wr2TT~
().findByNamedQuery(query, parameters); zJOL\J'
} |I6\_K.=L
b v~"_)C
publicList find(finalString query){ =rGjOb3+
return getHibernateTemplate().find BH0].-)[y!
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(query); i_Ab0vye
} rOEk%kJ
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publicList find(finalString query, finalObject V`m'r+ Y
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parameter){ ".Luc7
return getHibernateTemplate().find ~A(fn:d
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(query, parameter); 9s7sn*aB#5
} :'|%~&J
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public PaginationSupport findPageByCriteria \ym3YwP4/:
.Ce30VE-
(final DetachedCriteria detachedCriteria){ 9{]U6A*K0w
return findPageByCriteria 1/:WA:]1,
l03{
ezJk[
(detachedCriteria, PaginationSupport.PAGESIZE, 0); gi#bU
} h(l4\)
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public PaginationSupport findPageByCriteria e3oHe1"hP
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(final DetachedCriteria detachedCriteria, finalint ZxFRE#y~2
Nk*d=vj
startIndex){ b"DaLwKkz
return findPageByCriteria FL*qV"r^n
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(detachedCriteria, PaginationSupport.PAGESIZE, 4+"2K-]
QH7"' u6
startIndex); #q#C_"
} _FR_6*C)5
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public PaginationSupport findPageByCriteria ]-]K4*{
4c^WQ>[
(final DetachedCriteria detachedCriteria, finalint G'<:O(Imu
Is57)(^.-
pageSize, (dmLEt
finalint startIndex){ }@6ws/5
return(PaginationSupport) bl yU53g
ZEa31[@B[
getHibernateTemplate().execute(new HibernateCallback(){ pZHx
publicObject doInHibernate )}w2'(!X8
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(Session session)throws HibernateException { 4~<78r5m
Criteria criteria = GYH{_Fq
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detachedCriteria.getExecutableCriteria(session); R `K1L!`3
int totalCount = -@bOFClE
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((Integer) criteria.setProjection(Projections.rowCount m-?hHdO
TP3KT)
()).uniqueResult()).intValue(); Ck1{\=t
criteria.setProjection tBUn
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}Um,wY[tK
(null); 0MpZdJ
List items = -So$f-y
U/ds(*g@
criteria.setFirstResult(startIndex).setMaxResults L;RHshTy
<8)cr0~zy>
(pageSize).list(); 0nr 5(4h
PaginationSupport ps = 65 ]>6D43
iy!SqC
new PaginationSupport(items, totalCount, pageSize, pYN.tD FO
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startIndex); 3ch<a0
return ps; iHa:6
} <S ae:m4
}, true); DyPHQ}G
} QJ\+u
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public List findAllByCriteria(final G22{',#r8
9QP- ~V{$
DetachedCriteria detachedCriteria){ ~n=oPm$pR
return(List) getHibernateTemplate _.%U}U
~Z`Cu~7
().execute(new HibernateCallback(){ 8 /vGA=
publicObject doInHibernate O\J{4EB@.
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w);jp;
(Session session)throws HibernateException { #_SsSD=.Sy
Criteria criteria = [CG3&J
U3**x5F_
detachedCriteria.getExecutableCriteria(session); p!o-+@ava
return criteria.list(); {h*)|J
} XjXz#0nR
}, true); 9ls*L!Jw
} 0^3n#7m;K
9^+E$V1@
public int getCountByCriteria(final 4iDqd
T@jv0/(+
DetachedCriteria detachedCriteria){ LzTdi%u$0|
Integer count = (Integer) 8'PK}heBU
WJJmM*>JW
getHibernateTemplate().execute(new HibernateCallback(){ WES$B7y
publicObject doInHibernate yUjkRT&h
cJE4uL<
(Session session)throws HibernateException { 4V&(w,zl
Criteria criteria = WF_v>g:g
<v6W
l\
detachedCriteria.getExecutableCriteria(session); s:K'I7_#@
return d@%PTSX
@# =yC.s
criteria.setProjection(Projections.rowCount KV)if'
x1h&`QUP
()).uniqueResult(); */HW]x|?V~
} ,8.$!Zia
}, true); Vx{
return count.intValue(); 7|xu)zYB
} @'A0Lq+#
} &5[B\yv
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用户在web层构造查询条件detachedCriteria,和可选的 naM~>N
g[*"LOw
startIndex,调用业务bean的相应findByCriteria方法,返回一个 R^mkQb>m.
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PaginationSupport的实例ps。 4jc?9(y%
u* G+=aV.6
ps.getItems()得到已分页好的结果集 jgiS/oW
ps.getIndexes()得到分页索引的数组 ][KlEE>W2
ps.getTotalCount()得到总结果数 LJ6l3)tpD
ps.getStartIndex()当前分页索引
2OpkRFFa
ps.getNextIndex()下一页索引 icX4n
ps.getPreviousIndex()上一页索引 ;aj;(Z.p)
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BU4IN$d0Po
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0}"\3EdAbD
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 YU" /p|!1
k s\q^ten
,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 E#_2t)20
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一下代码重构了。 Q"B8l[
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我把原本我的做法也提供出来供大家讨论吧: \|9B:y'y
[^?i<z{0C
首先,为了实现分页查询,我封装了一个Page类: 4I$Y"|_e
java代码: P3]K'*Dyd
4# PxJG6m
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/*Created on 2005-4-14*/ 0O,;[l
package org.flyware.util.page; Ow*va\0
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/** FZn1$_Svr
* @author Joa iLIb-d?!a&
* 2J{vfF
*/ CuH4~6
publicclass Page { ?P-O4
)DhE~
/** imply if the page has previous page */ \Cu=Le^
privateboolean hasPrePage; yf0v,]v[
%3~miP
/** imply if the page has next page */ >\^oCbqF}~
privateboolean hasNextPage; `,xO~_
e>
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/** the number of every page */ Jz>P[LcB
privateint everyPage; Za1mI^ L1
xT_"` @
/** the total page number */ ?8{Os;!je
privateint totalPage; >qB`03>
=DfI^$Lr:
/** the number of current page */ /KWdIP#
privateint currentPage; bR)P-9rs
V\x'w*FP
/** the begin index of the records by the current vT0Op e6m
>oWPwXA
query */ 'DVn /3?X
privateint beginIndex; L=qhb;[L
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/** The default constructor */ )K@D4sl
public Page(){ HBR/" m
G gA:;f46
} *X$qgSW
J)B3o$
/** construct the page by everyPage SQ> Yf\
* @param everyPage ]:D&kTc
* */ Q2Ey RFT
public Page(int everyPage){ 6Aqv*<1=62
this.everyPage = everyPage; z+;$cfN
} 0J'Cx&Rg
Jj[3rt?8
/** The whole constructor */ XrTc5V
public Page(boolean hasPrePage, boolean hasNextPage, CHv
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5JVBDA^#om
int everyPage, int totalPage, ,&4
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int currentPage, int beginIndex){ fJ.=,9:<
this.hasPrePage = hasPrePage; 8aVQW_m}
this.hasNextPage = hasNextPage; *(q{k%/M
this.everyPage = everyPage; m`fdf>gWp
this.totalPage = totalPage; EH2):
this.currentPage = currentPage; M5+R8ttc
this.beginIndex = beginIndex; ag:<%\2c
} T+P{,,a/]
/G7^ l>pa
/** {@7UfJh>
* @return rjcH[U(
* Returns the beginIndex. 2 N &B
*/ @(a~p
publicint getBeginIndex(){ 4IfkYM
return beginIndex; M^WoV
}'
} M_E$w$l2<
crt
)}L8-
/** !V6O~#
* @param beginIndex bI,gNVN=
* The beginIndex to set. [BpIzhy&}
*/ jz%%r Q(
publicvoid setBeginIndex(int beginIndex){ Tc DkKa
this.beginIndex = beginIndex; M@V.?;F},
} XJ|CC.]1u
:i&ZMH,O
/** z;_fO>u:
* @return 9w Pc03a
* Returns the currentPage. >t,BNsWB
*/ h98_6Dw(]
publicint getCurrentPage(){ (CRY$+d
return currentPage; 8T:|~%Sw
} 8#9di
yE(> R(^
/** J3oj}M*
* @param currentPage "-'w,g
* The currentPage to set. a3wTcp "r
*/ MjAF&bD^
publicvoid setCurrentPage(int currentPage){ Ub%al
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this.currentPage = currentPage; d?RKobk
} ik@g; >pQD
I-E}D"F;p[
/** 0jsU^m<g
* @return bY4~\cP.
* Returns the everyPage. =rV*iLy
*/ Ng?n}$g*
publicint getEveryPage(){ )p&FDK#ob=
return everyPage; d~](S<k
} X&1R6O
$d4^e&s
/** uUUj?%
* @param everyPage OTA @4~{C
* The everyPage to set. Y|t] bb
*/ ;?>xuC$
publicvoid setEveryPage(int everyPage){ 28u)q2s^W|
this.everyPage = everyPage; TbqED\5@9w
} fZ2>%IxG}
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/** 3%?01$k
* @return !7MC[z(|N
* Returns the hasNextPage. @|:_ ?
*/ 7q>WO
publicboolean getHasNextPage(){ b[<zT[.:
return hasNextPage; {{c/:FTEU
} $=7[.z&
eDkJ+5b
/** Z'!Ii+'6
* @param hasNextPage Vi9Kah+
* The hasNextPage to set. a_z1S Z2[
*/ z^,P2kqK_
publicvoid setHasNextPage(boolean hasNextPage){ 5MX7V4ist
this.hasNextPage = hasNextPage; = Z
/*
} UlNx5l+k
QgF2f/;!
/** .]XBJc
* @return v#^ _|
* Returns the hasPrePage. kac-@
*/ dy"7Wl]hi7
publicboolean getHasPrePage(){ &P pb2
return hasPrePage; R+&{lc
} ?B{,%2+
prw% )#,
/** #Fkn-/nL
* @param hasPrePage *L{^em#b
* The hasPrePage to set. nN'>>'@>
*/ APUpqY
publicvoid setHasPrePage(boolean hasPrePage){ cgV5{|P
this.hasPrePage = hasPrePage; w+][L||4c
} |-Q="7b%
UA3!28Y&E3
/** Yc`PK =!l
* @return Returns the totalPage. KN<KZM
* ],|;
*/ Ue&I]/?;$
publicint getTotalPage(){ [M#I Nm}
return totalPage; /P[ @o
} SYYg
2I
]N^>>k
/** yD yMI
* @param totalPage GswV/V+u
* The totalPage to set. z{(c-7*
*/ f>[!Zi*
publicvoid setTotalPage(int totalPage){ LTZ~Id-)P
this.totalPage = totalPage; V8947h|&
} F7&Oc)f"B
q^Ui2
} )YPut.
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Tw1u
F* _ytL
jc7NYoT:
|bX{MF
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 |>dqZ_)v
mNQ*YCq.
个PageUtil,负责对Page对象进行构造: 55V&[>|K5
java代码: {SwvUWOf"
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W@WKdaJ
/*Created on 2005-4-14*/ fctVJ{?
package org.flyware.util.page; D8=a +!l-
W~?mr!`
import org.apache.commons.logging.Log; KY9&Ky+2 B
import org.apache.commons.logging.LogFactory; ^~DClZ
:rnj>U6<>
/** 9V?:!%J
* @author Joa _8s1Wh G
* =`f"8,5
*/ K&;;{~md.
publicclass PageUtil { A08{]E#v>
F(;95TB
privatestaticfinal Log logger = LogFactory.getLog e)kVS}e?
2@?\"kR"!
(PageUtil.class); lk%W2N5
Wu
U_RE
/** 9RnXp&w
* Use the origin page to create a new page k(R&`
* @param page >OW>^%\!1
* @param totalRecords r1AG1Y
* @return -n]E\"
*/ q|xic>.
publicstatic Page createPage(Page page, int RrRE$g
EM0]"s@Lf
totalRecords){ :'K%&e?7s
return createPage(page.getEveryPage(), >@i{8AD
M|\C@,F]8
page.getCurrentPage(), totalRecords); "Rq)%o$Z
} '/GZ,~q
FW,@.CX
/** yUlYf#`H
* the basic page utils not including exception YY9Ub
A"no!AN
handler D",~?
* @param everyPage K91.-k3)$
* @param currentPage ZE"Z_E;r
* @param totalRecords TptXH?
* @return page [B" CNnA
*/ 5d5q0bb
publicstatic Page createPage(int everyPage, int jjU("b=
V0a)9\x(\
currentPage, int totalRecords){ -A;4""
everyPage = getEveryPage(everyPage); c(!8L\69V}
currentPage = getCurrentPage(currentPage);
>TQnCG=
int beginIndex = getBeginIndex(everyPage, B4ky%gF4
X7{ h/^
currentPage); wwh)B92Y5
int totalPage = getTotalPage(everyPage, @Sd l~'"
4Q5c'
totalRecords); Sp^jC
Xu
boolean hasNextPage = hasNextPage(currentPage, RlnJlY/
Hsi<!g.
totalPage); >2@ a\
boolean hasPrePage = hasPrePage(currentPage); e+7x &-+
^.;
x
returnnew Page(hasPrePage, hasNextPage, BuIly&qbm<
everyPage, totalPage, A3c&VT6Q
currentPage, t}2$no?
4KCJ(<p|
beginIndex); &a];"2
} SVc5mS|up
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privatestaticint getEveryPage(int everyPage){ /ng+IC3
return everyPage == 0 ? 10 : everyPage; okv`v
({
} _/%,ZoZ2
3^J~ts{*
privatestaticint getCurrentPage(int currentPage){ E#A}J:
return currentPage == 0 ? 1 : currentPage; !
fSM6Vo
} t ]yD95|
@[(<oX%
privatestaticint getBeginIndex(int everyPage, int (XJ0?;js=
p.J+~s4G
currentPage){ 1} h''p
return(currentPage - 1) * everyPage; =zXii{t
} X`E3lgfqT
Bm&% N?9
privatestaticint getTotalPage(int everyPage, int tW#=St0<.o
N&'05uWY}
totalRecords){ FELTmQUV
int totalPage = 0; r:*0)UZlD
Z UCz-53
if(totalRecords % everyPage == 0) hJcN*2\:
totalPage = totalRecords / everyPage; "Ooc;xD3<
else Jf|6 FQo&
totalPage = totalRecords / everyPage + 1 ; l{b*YUsz>
,F)9{ <r]
return totalPage; 5v@-.p
} @p}"B9h*^
si|DxDx
privatestaticboolean hasPrePage(int currentPage){ DRUvQf
return currentPage == 1 ? false : true; x!@P|c1nKC
} L&s|<<L
hR1n@/nh
privatestaticboolean hasNextPage(int currentPage, E0Neo _7
L1i:hgq0]
int totalPage){ L[s8`0
return currentPage == totalPage || totalPage == Ws>2S
bEz1@"~
p
0 ? false : true; ^&mJDRe
} 78[5@U
; OpN&q+
]J%p&y+6
} jQc.@^#+x
%tRQK$]c
#& 5}
].C4RH
@Ht7^rz+S
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。 68k
W$X@DXT=o
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 X>`5YdT~+
_CDl9pP36#
做法如下: <7;AK!BH
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 apxY2oE&
^*fZ
的信息,和一个结果集List: &S8Pnb)d
java代码: ief~*:5
0;bi*2U
:172I1|7
/*Created on 2005-6-13*/ fZ*LxL
package com.adt.bo; [4_JK
Vif0z*\e{
import java.util.List; _FJ,, /~
aj71oki)
import org.flyware.util.page.Page; B)bq@jM
SX4"HadV>
/** *<[Nvk^
* @author Joa M,ObzgW
*/ 5:o$]LkOWC
publicclass Result { O"<W<l7Q
fW,,@2P
private Page page; \VTNXEw*G
jv
C.T]<B
private List content; FccT@,.F
@4'bI)
/** %L\buwjy$
* The default constructor (|F } B
*/ >brf7h
public Result(){ oBm^RHTZ
super(); #ZPU.NNT?
} ,1s,G]%M
?ep'R&NV
/** Zy>iaG9}
* The constructor using fields Kf.G'v46
* }nQni?
* @param page `o.DuvQ
E
* @param content "K"]/3`k-
*/ lDQ'
public Result(Page page, List content){ F%8W*Y699
this.page = page; @-~
)M_
this.content = content; L+c7.l.yT
} cPemrNxydN
C{i9~80n
/** M%3 \]&
* @return Returns the content. abHW[VP9
*/ .)7r /1o
publicList getContent(){ 3N'f Hy
return content; yN0!uzdW*
} #q06K2
:N826_q
/** :%!}%fkxH
* @return Returns the page. 6a+w/IO3OU
*/ =?*6lS}gy
public Page getPage(){ 5kK:1hH7
return page; 3H_mR
j9th
} p m4g),s
a cSm+t
/** |NbF3 fD
* @param content m#D+Yh/y{n
* The content to set. $#cZJ@;]
*/ sG/mmZHYzr
public void setContent(List content){ JQ>GKu~
this.content = content; t8"*jt
} l1_Tr2A}7/
D^?jLfW8
/** 23lLoyN
* @param page n~1'M/wh
* The page to set. W>ziA
*/ '`-W!g[
>
publicvoid setPage(Page page){ _f~(g1sE
this.page = page; 73-*|@6
} ;g3z?Uz)
} %:v59:i}
3'd(=hJ45$
~wMdk9RQ
'IorjR@40
L[]*vj
2. 编写业务逻辑接口,并实现它(UserManager, |WopsV
%
;XJK*QDN
UserManagerImpl) !)jw o=l}J
java代码: y:U'3G-
oD$8(
IL:d`Kbqf
/*Created on 2005-7-15*/ +E8Itb,
package com.adt.service; TZ`@pDi
DCJmk6p%0
import net.sf.hibernate.HibernateException; AL%gqt]
ugtzF
import org.flyware.util.page.Page;
T 4}SF
yI&{8DCCw
import com.adt.bo.Result; [m9Pt]j@
ISQC{K']J
/** $/\b`ID
* @author Joa b#**`Y
*/ 16iymiLz&
publicinterface UserManager { 'bH',X8gF
$jt UQ1
public Result listUser(Page page)throws "2>I?
=j)y.x(
HibernateException; Fq{Z-yVp
rAc
Yt9M#
} Z_Gb9
64Ot`=A"
.U8Se+;
87/!u]q
PGT*4r21
java代码: 2<dl23
NDG3mCl
b&LfL$
/*Created on 2005-7-15*/ Hx}K
wS
package com.adt.service.impl; <Tq&Va_w
QN %w\JXS
import java.util.List; cJEOwAN
(S:+#v
import net.sf.hibernate.HibernateException; dcFqK~
~<M/<%o2*
import org.flyware.util.page.Page; VS$ZR'OP0
import org.flyware.util.page.PageUtil; j@1rVOmK
KFCL|9P
import com.adt.bo.Result; IAr
import com.adt.dao.UserDAO; +/ A`\9QT
import com.adt.exception.ObjectNotFoundException; }$K2h*
import com.adt.service.UserManager; m){.{Vn]
N-x~\B!
/** Qm|Q0u
* @author Joa $#4J^(I*:
*/ j1!P:(
publicclass UserManagerImpl implements UserManager { Oeo:V"
]Gw? DD|Gn
private UserDAO userDAO; Zk+J= Cwq}
;T0Y=yC
/** B/IPG~aMEZ
* @param userDAO The userDAO to set. >wK ^W{
*/ p100dJvq
publicvoid setUserDAO(UserDAO userDAO){ oE+s8Q
this.userDAO = userDAO; h&7]Bp
} )oO cV%
?Gq'r2V
/* (non-Javadoc) !B==cNq
* @see com.adt.service.UserManager#listUser %0]vW;Q5
Lc>9[!+#
(org.flyware.util.page.Page) M\wIpRD,
*/ G Q&9b_
public Result listUser(Page page)throws k^q}F%UV
3F,$}r#
HibernateException, ObjectNotFoundException { #C?T
int totalRecords = userDAO.getUserCount(); [/#c9RA
if(totalRecords == 0) gY AXUM,
throw new ObjectNotFoundException TlExw0i!
$tyF(RybG
("userNotExist"); KWU
~QAc
page = PageUtil.createPage(page, totalRecords); T ,,
Ao36
List users = userDAO.getUserByPage(page); pv2_A
returnnew Result(page, users); o5 6_t{<
} EG5'kYw2
Wjt1NfS&
} q!#e2Dx
F]~ rA! g1
_8C0z=hz
-If-c'"G
i^ 9PiP|U
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 8tWOVLquJ
*F+t`<2
询,接下来编写UserDAO的代码: v\*43RL
3. UserDAO 和 UserDAOImpl: ]%I cUd}
java代码: aH)$#6${Ap
D%v4B`4ua'
@psyO]D=j%
/*Created on 2005-7-15*/ ReOp,A/y
package com.adt.dao; y@[}FgVOh
Evkb`dU3n
import java.util.List; OKfJ
J=4R" _yo
import org.flyware.util.page.Page; O=}4?Xv
&LE,.Q34
import net.sf.hibernate.HibernateException; &eV& +j
n(.y_NEgV!
/** 3vPb}
* @author Joa U@+
@Mc
*/ ]Q=D'1MM
publicinterface UserDAO extends BaseDAO { *6~ODiB
)xiiTkJd5
publicList getUserByName(String name)throws 6k;__@B,
zyTP|SXk
HibernateException; |R:gu\gG
y0qrl4S)v
publicint getUserCount()throws HibernateException; +MPM^ m
eRQ}`DjTk
publicList getUserByPage(Page page)throws {dJC3/Rf
kf+]bV
HibernateException; \o9-[V#Gm
~H/|J^ J
} _f$8{&`k
/>;1 }
jr{C/B}
2yR*<yj
\]}|m<R
java代码: H];|<G
*@=in7*c
. $uvQpyh
/*Created on 2005-7-15*/ R%o:'-~
package com.adt.dao.impl; qEr2Y/:i"
6 ]W!>jDc
import java.util.List; B7(~m8:eH7
]&\HAmOQS
import org.flyware.util.page.Page; \y^ Od7F
zu'Uau
import net.sf.hibernate.HibernateException; XVAyuuTg\
import net.sf.hibernate.Query; | 2BIAm]
"Wr5:T-;
import com.adt.dao.UserDAO; %"PG/avo
!TY9\8JzV
/** !/+ZKx("9
* @author Joa zF6R\w
*/ 84^'^nd
public class UserDAOImpl extends BaseDAOHibernateImpl 3^
~M7=k
7l> |G,[c
implements UserDAO { Jm$.$B&I
[2#5;')
/* (non-Javadoc) Nq1la8oQ3
* @see com.adt.dao.UserDAO#getUserByName =LV7K8FSd
=gS?atbX
(java.lang.String) o&P}GcEIw
*/ OQMkpX-dH
publicList getUserByName(String name)throws $X8(OS5d'
{'VP_ZS1v
HibernateException { 1S9(Zn[2,
String querySentence = "FROM user in class S[,!
1>P[3Y@}
com.adt.po.User WHERE user.name=:name"; Z"PPXv-<jY
Query query = getSession().createQuery :;W[@DeO[
&v|Uy}h&%1
(querySentence); \7PPFKS
query.setParameter("name", name); {Vw+~8
return query.list(); :)VO,b~r
} l+!!S"=8)~
uKc x$
/* (non-Javadoc) <WFA3
* @see com.adt.dao.UserDAO#getUserCount() zWKnkIit,
*/ )[RLCZ
publicint getUserCount()throws HibernateException { r(;oDdVc
int count = 0; H'k $<S
String querySentence = "SELECT count(*) FROM /a.4atb0
li'h&!|]
user in class com.adt.po.User"; k7JE{(Ok
Query query = getSession().createQuery i
,Cvnp6Lv
gU\pP,a
(querySentence); >B>[_8=f@
count = ((Integer)query.iterate().next /jl{~R#1
0WT]fY?IS
()).intValue(); y4*i
V;"
return count;
[U9b_`
} _:@~bHd
m(CW3:|
/* (non-Javadoc) 8:=&=9%
* @see com.adt.dao.UserDAO#getUserByPage vD<6BQR
n%'M?o]DF
(org.flyware.util.page.Page) sd4eJ
*/ kQ~2mU
publicList getUserByPage(Page page)throws s~e<Pr?yu
R_9 &V!fl
HibernateException { e_'/4
n
String querySentence = "FROM user in class iV9wqUkMv
Z]?Tx2|7
com.adt.po.User"; Mx9#YJ?t~
Query query = getSession().createQuery DV+M;rs
;W%nBdE6|
(querySentence); X&C&DTB
query.setFirstResult(page.getBeginIndex()) fP3e{dVf
.setMaxResults(page.getEveryPage()); ?88k`T'EI
return query.list(); fH#yJd2?f
} dRwOt
AI
KLJvte
} !ieMhJ5r
&L7u//
WM y97*L<
7AwV4r*:
?%RAX CK
至此,一个完整的分页程序完成。前台的只需要调用 A:|dY^,:?*
h>Z NPP8N
userManager.listUser(page)即可得到一个Page对象和结果集对象 <Q57}[$*)
E/bIq}R6
的综合体,而传入的参数page对象则可以由前台传入,如果用 1.S7MSpTV
:`u?pc27Sm
webwork,甚至可以直接在配置文件中指定。 s|er+-'
MZYh44
下面给出一个webwork调用示例: _#[~?g`
java代码: ? :StFlie
LDg"s0n#
8CXZ7 p
/*Created on 2005-6-17*/ b1+6I_u.
package com.adt.action.user; "ijpqI
~nit~;
import java.util.List; vjo@aY.x
nP]tc
import org.apache.commons.logging.Log; 3=[#(p:
import org.apache.commons.logging.LogFactory; @8keLrp
import org.flyware.util.page.Page; E lf'1
0!4;."S
import com.adt.bo.Result; fPXMp%T!
import com.adt.service.UserService; m(2(Caz{
import com.opensymphony.xwork.Action; hKkUsY=R
sb1Zm*m6
/** cb36 ~{
* @author Joa [^N8v;O
*/ mT]+wi&
publicclass ListUser implementsAction{ !T+jb\O_
^pI&f{q
privatestaticfinal Log logger = LogFactory.getLog z@70{*
? PIq/[tk
(ListUser.class); ]lBe
:ik$@5wp
private UserService userService; VV_Zrje
l ~bjNhk
private Page page; M<Gr~RKmAn
4Sj;38F
.1
privateList users; D\~s$.6B
"hE/f~\
/* ;HKb
* (non-Javadoc) / 7i>0J]
* 7z.(pg=
* @see com.opensymphony.xwork.Action#execute() tQ:g#EqL9B
*/ ^*6So3
publicString execute()throwsException{ "7w~0?}
Result result = userService.listUser(page); 4=;.<
page = result.getPage(); bHJKX>@{
users = result.getContent(); uq/z.m
return SUCCESS; Y 6NoNc]h
} Mz?xvP?z
_oV;Y`_
/** NZu\ Ae
* @return Returns the page. i146@<\G{P
*/ P M
x`PB
public Page getPage(){ FJ/>=2^B
return page; fX:)mLnO/
} >DFpL$oP
%VV\biO]
/** 2#srecIz-!
* @return Returns the users. OpNTyKbaD
*/ |"K<
publicList getUsers(){ |8QXjzH
return users; ^#6"d+lp
} cWNZ +Q8Y
pCB^\M%*
/** bqo+b{i\
* @param page 3`Ug]<m
* The page to set. gs xT
*/ fXL&?~fS
publicvoid setPage(Page page){ D.!ay>o0#
this.page = page; P#8+GN+bF
} d`XC._%^J
Czl4^STiC
/** ZqDanDM
* @param users jfLkp>2E'
* The users to set. YK=o[nPmK
*/ P' ";L6h
publicvoid setUsers(List users){ m'!smSx8
this.users = users; tRUGgf`
} hc2AGeZr
0xN1Xm0d
/** Wzn!BgxRr
* @param userService @4O;dFOQ)
* The userService to set. q7z;b A
*/ -T,/S^
publicvoid setUserService(UserService userService){ Wl29xY}`{!
this.userService = userService; A"Prgf
eT
} -(Zi
} h/LlH9S:!
Gz_[|,i
A^%li^qz
MV(Sb:RZ
#"T< mM7
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, ]_hrYjX;
Tc3~~ X
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 w !5@PJ)~U
8et*q3D7`
么只需要: Q#h*C
ZT
java代码: 5z T~/6-(
x;w^&<hQ\
Ala~4_" WL
<?xml version="1.0"?> (V06cb*42[
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork #W]4aZ1
].!^BYNht
1.0//EN" "http://www.opensymphony.com/xwork/xwork- nt5x[xa
c; MF
1.0.dtd"> rw|;?a0
en5sqKqh+
<xwork> |_}
LMkU)
e7$ZA#A_5v
<package name="user" extends="webwork- }|Ao@UvH
2_i9
q>I
interceptors"> `\pv^#5HV9
NI%&Xhn!*>
<!-- The default interceptor stack name MjNq8'$"
+HpPVuV
--> .boBo$f
<default-interceptor-ref q!O B?03n
drM@6$k
name="myDefaultWebStack"/> }JWLm.e
ov9+6'zya
<action name="listUser" $Ith8p~
=.Hq]l6+
class="com.adt.action.user.ListUser"> V~~4<?=A
<param 6F)^8s02h
: g+5cs
name="page.everyPage">10</param> 01_*^iCf5
<result 2X)n.%4g$;
sx]kH$
name="success">/user/user_list.jsp</result> rYP72<
</action> [2l2w[7Rid
C-:lM1
</package> l`wF;W!
d$?sS9"8(
</xwork> ]}za
:p|wo"=@Ge
3%0ShMFP@
q-lejVS(g
Ht,dMt>:
gAPD
y/wM
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 .:U`4->E
&%\H170S
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 ^F? }MY>
[vV5@nP:
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 ;&2f {
'Y;M%
TJ_pMU
J>dIEW%u
WvN{f*
我写的一个用于分页的类,用了泛型了,hoho _L%
=Q ulu
HaA2y
java代码: _uq[D`=
p?V@P6h
oXFo
package com.intokr.util; G/N 1[)
:v B9z
import java.util.List; r0/aw
P<C=9@`!
/** qtlcY8!
* 用于分页的类<br> rr^?9M*{V
* 可以用于传递查询的结果也可以用于传送查询的参数<br> =Q~@dP
* 3XSfXS{lwP
* @version 0.01 21sXCmYR,t
* @author cheng lnQY_~s
*/ 1"S~#
public class Paginator<E> {
ni?5h5-
privateint count = 0; // 总记录数 @
D.MpM}~
privateint p = 1; // 页编号 L/xTW
privateint num = 20; // 每页的记录数 /2>.*H_2
privateList<E> results = null; // 结果 1!W'0LPM
o0 |T<_
/** 8 -YC#&
* 结果总数 1b,MJ~g$
*/ c>%%'c
publicint getCount(){ g+]o=@
return count; YB]{gm2
} Y2aN<>f
cvVv-L<[S`
publicvoid setCount(int count){ #CRd@k?
this.count = count; KnC:hus
} 5S
4Bz
|_mN:(3
/** zuS4N?t`p
* 本结果所在的页码,从1开始 I9L7,~s
* 8EY]<#PN
* @return Returns the pageNo. ]([^(&2
*/ ?izl#?
publicint getP(){ u;9a/RI
return p; |#ZMZmo{
} [Om,Q<
u] Z;Q_=
/** !3)WW)"!r
* if(p<=0) p=1 `r]C%Y4?
* ;r}yeISf
* @param p <72q^w
*/ IXpn(vX
publicvoid setP(int p){ g(dReC
if(p <= 0) 4q\&Mb3
p = 1; rgF4 W8
this.p = p; Nxr\Yey
} *uoO#4g~
fZb}-
/** ]GBlads
* 每页记录数量 (0["|h32,
*/ hC?rHw
H>
publicint getNum(){ 6w~Cyu4Ov
return num; nP_)PDTFp
} 40G'3HOp
!oYNJE Y7
/** ! ~tf0aY
* if(num<1) num=1 aSMoee@!
*/ uH)?`I\zrd
publicvoid setNum(int num){ h@dy}Id
if(num < 1) i,wZNX
num = 1; SqZ .}s
this.num = num; Dt\rrN:v
} OZEbs 7
Q/0oe())
/** .DM-&P
* 获得总页数 qRHT~ta-?
*/ *T~b
ox
publicint getPageNum(){ <H$!OPV
return(count - 1) / num + 1; / ;+Mz*
} u4$R ZTC
BjGfUQ
/** ^6J*:(eM
* 获得本页的开始编号,为 (p-1)*num+1 ^SK!?M
*/ b,X+*hRt
publicint getStart(){ }X. Fm'`
return(p - 1) * num + 1; hkdF
} *5{1.7
#8~ygEa}
/**
: 76zRF
* @return Returns the results. [SD
mdr1T$
*/ q[9N4nj$<
publicList<E> getResults(){ =
5[%%Lf
return results; P-<1vfThH
} +d7Arg!m
w@Asz9Lq%
public void setResults(List<E> results){ 3D^cPkX
this.results = results; O3mw5<%15
} {rK]Q! yj
5{#s<%b.
public String toString(){ /8!n7a7
StringBuilder buff = new StringBuilder mn\A)RQ
3V7WIj<
(); 9dm<(I}
buff.append("{"); "n)AlAV@
buff.append("count:").append(count); Xvoz4'Gme
buff.append(",p:").append(p); Bl^BtE?-b
buff.append(",nump:").append(num); ><S(n#EB
buff.append(",results:").append NCY2^
3rd8mh&l
(results); 'Ebjn>"
buff.append("}"); JVxja<43
return buff.toString(); tCm]1ZgRW
} 8vtembna4
z'Z[mrLq
} &,=FPlTC=
KV8<'g +2?
h&n1}W+