Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 )%j"
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 b! tludb
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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 nQLs<]h1
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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 i21QJ6jPcI
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。 JvJ;bFXD
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分页支持类: p_6P`Yx^e
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java代码: QJXdb]Y^;
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package com.javaeye.common.util; R^tcr)(
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import java.util.List; 6>B \|
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publicclass PaginationSupport { +by|
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publicfinalstaticint PAGESIZE = 30;
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privateint pageSize = PAGESIZE; t)(v4^T
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privateList items; 3B#!2|
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privateint totalCount; b]#~39Iph
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privateint[] indexes = newint[0]; _85E=
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privateint startIndex = 0; 0w}{(P;
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public PaginationSupport(List items, int uI9lK
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totalCount){ v=Mz I#0L
setPageSize(PAGESIZE);
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setTotalCount(totalCount); W-XN4:,qI
setItems(items); *1v_6<;2i<
setStartIndex(0); 8Mb$+^zU
} R `Q?J[e
yu_gNro L
public PaginationSupport(List items, int 7b,AQ9
{~1M
totalCount, int startIndex){ Dauo(Uhuo
setPageSize(PAGESIZE); ^Kum%<[i
setTotalCount(totalCount); =U_@zDD@V
setItems(items); d<?X3&J
setStartIndex(startIndex); x`3.Wu\
} !Iko0#4i
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public PaginationSupport(List items, int 2w7@u/OC'
b)y<.pS\
totalCount, int pageSize, int startIndex){ 0k7"H]J
setPageSize(pageSize); cuNq9y;[
setTotalCount(totalCount); vT}pbOTh
setItems(items); JrxP,[qJG
setStartIndex(startIndex); U)b&zZc;
} 6d(b'S^
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publicList getItems(){ KZ
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return items; -%N}A3m!5
} {{GHzW
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publicvoid setItems(List items){ P^n{Y~P=Q
this.items = items; "pl[(rc+u
} @OrXbG7&>#
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publicint getPageSize(){ &U854
return pageSize; uRs9}dzv
} _"`uqW79
/$<JCNGv
publicvoid setPageSize(int pageSize){ %Ln?dF+
this.pageSize = pageSize; H|x k${R`
} 0sY#MHPT&
xQZMCd
publicint getTotalCount(){ J$<:/^t
return totalCount; ^M"HSewo
} 8L@UB6b\
64;oB_
publicvoid setTotalCount(int totalCount){ dUUPhk0
if(totalCount > 0){ h^Arb=I
this.totalCount = totalCount; C-_w]2MM
int count = totalCount / b^@`uDb6
M_|M&lR>
pageSize; / *Ou$
if(totalCount % pageSize > 0) i:AjWC@]
count++; nqUH6(
indexes = newint[count]; 56VE[G
for(int i = 0; i < count; i++){ [%7IQ4`{
indexes = pageSize * a [0N,t
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i; xu0;a
} dawVE
O
}else{
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this.totalCount = 0; CvgPIrl
} F<H`8*q9
} ZY~zpC_
&8IWDx.7}
publicint[] getIndexes(){ =]2
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return indexes; eimA *0Cq
} ?Aj\1y4L1
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publicvoid setIndexes(int[] indexes){ ,dGFX]P
this.indexes = indexes; l;"ub^AH
} W ??;4
k4]R]=Fh.
publicint getStartIndex(){ ksxO<Y
return startIndex; ]Hv*^Bak
} rjhs?
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publicvoid setStartIndex(int startIndex){ )&g2D@+{
if(totalCount <= 0) 3ZT/>a>@
this.startIndex = 0; tF{{cd
elseif(startIndex >= totalCount) bdNY 7|j`
this.startIndex = indexes \=
)[
x`/m>~_
[indexes.length - 1]; s8/ozaeo
elseif(startIndex < 0) 9;m#>a@Y
this.startIndex = 0; /It.>1~2@
else{ _Ct@1}aa4x
this.startIndex = indexes
b{9HooQ{
;[;S_|vZ=)
[startIndex / pageSize]; H>@JfYZ0
} >TH-Q[
} q70YNk}
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publicint getNextIndex(){ RBHqLg(
int nextIndex = getStartIndex() + )dzjz%B)
^5^
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pageSize; [hvig$L
if(nextIndex >= totalCount) iq[2H$
return getStartIndex(); reD[j,i&t.
else D8<0zxc=(
return nextIndex; SWe!9Y$
} b ?=
uBd =x<c\
publicint getPreviousIndex(){ ).O\O)K
int previousIndex = getStartIndex() - ;]8p:ME
@EH4N%fH
pageSize; 'J&@jp
if(previousIndex < 0) 1^Y:XJ73
return0; 9\W5
else
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return previousIndex; 0B!mEg
} t9=|* =;9)
&p(*i@Ms
} F#3$p$;B$
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抽象业务类 R4K eUn"
java代码: k6 h^
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/** LI5cUCl
* Created on 2005-7-12 ]#Z$jq{,
*/ ZLFdnC@
package com.javaeye.common.business; C[/Uy
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import java.io.Serializable; 1.cUolnr
import java.util.List; tMs|UC
SieV%T0t1
import org.hibernate.Criteria; w7]p9B
import org.hibernate.HibernateException; @bVh?T0~F,
import org.hibernate.Session; ^.$r1/U
import org.hibernate.criterion.DetachedCriteria; Wb-'E%K
import org.hibernate.criterion.Projections; ]|\>O5eeu
import 2H32wpY
,l
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org.springframework.orm.hibernate3.HibernateCallback; Z+pvdu
import ~d<`L[
-uY:2
org.springframework.orm.hibernate3.support.HibernateDaoS 5|B(K @<
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upport; '| Q*~Lh
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import com.javaeye.common.util.PaginationSupport; aN);P>
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public abstract class AbstractManager extends #I@[^^Vw
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HibernateDaoSupport { ObHz+qRG
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privateboolean cacheQueries = false; QH?2v
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privateString queryCacheRegion; `[HoxCV3o
t2%bHIG}
publicvoid setCacheQueries(boolean /3:IE%o
K d|l\k!
cacheQueries){ wQ/@+$>
this.cacheQueries = cacheQueries; >C d&K9H
} [T?6~^m=
)-Sl/G
publicvoid setQueryCacheRegion(String @42lpreT
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queryCacheRegion){ q,h.W JI
this.queryCacheRegion = 4O,a`:d1$6
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queryCacheRegion; F#C 6.`B
} U3iyuE
kQiW 5
publicvoid save(finalObject entity){ /r 2.j3:l
getHibernateTemplate().save(entity); VH1c)FI
} c3 ]^f6)?
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publicvoid persist(finalObject entity){ yA )+-
getHibernateTemplate().save(entity); +OuG!3+w
} lNnbd?D8
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publicvoid update(finalObject entity){ [tw<TV"\
getHibernateTemplate().update(entity); ENF@6]
} 9%'HB\A
thboHPml{
publicvoid delete(finalObject entity){ *[/Xhx"
getHibernateTemplate().delete(entity); ?fX8WRdh
} !(AFT!
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publicObject load(finalClass entity, `pS)qx.a
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finalSerializable id){ Kpbber
return getHibernateTemplate().load P\4o4MF@K
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(entity, id); 03jBN2[!
} XA^:n+Yo
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publicObject get(finalClass entity, 'cc4Y~0s
Tk=3"y+u[
finalSerializable id){ ^i k|l=
return getHibernateTemplate().get . T>}O0L"
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(entity, id); 2gI_*fG1
} QnAf A%
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publicList findAll(finalClass entity){ a;6\T*iJ!
return getHibernateTemplate().find("from Ln
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" + entity.getName()); @*{BX~f
} Xr;noV-X
bo/!u
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publicList findByNamedQuery(finalString I,uu>-
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namedQuery){ eBKIdR%k
return getHibernateTemplate *N+aZV}`Z
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().findByNamedQuery(namedQuery); uk/+
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} V2* |j8|
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publicList findByNamedQuery(finalString query, E%:zE Q
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finalObject parameter){ BC[d={_-
return getHibernateTemplate Wm&f+{LO+K
$q+`GXc-
().findByNamedQuery(query, parameter); JNl+UH:.
} ;z=C]kI6M
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publicList findByNamedQuery(finalString query, xT8"+}
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finalObject[] parameters){ Kn\(Xd.>
return getHibernateTemplate >Tx;<G
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().findByNamedQuery(query, parameters); JH;DVPX9z
} 4!qDG+m
vw;
publicList find(finalString query){ _q$fw&
return getHibernateTemplate().find C(Y6t1
:.Sc[UI0
(query); g3 rFJc
} {`zF{AW8q
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publicList find(finalString query, finalObject t"Hrn3w
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parameter){ wQ^a2$Z
return getHibernateTemplate().find :W.(,65c
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(query, parameter); 2ow\d b
} N|LVLsK
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public PaginationSupport findPageByCriteria lukV
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(final DetachedCriteria detachedCriteria){ ]f~YeOB@
return findPageByCriteria l$KcS&{w9
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); %"2B1^o>
} b4ivWb |`
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public PaginationSupport findPageByCriteria }6N|+z.cU
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(final DetachedCriteria detachedCriteria, finalint `yXy T^
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startIndex){ B)dynGF8i
return findPageByCriteria sSK$
@=c='V]
(detachedCriteria, PaginationSupport.PAGESIZE, k:xV[9ev:
+s}28U!
startIndex); u<zDZ{jt)
} vGw}e&YI
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public PaginationSupport findPageByCriteria Y."[k&P-
8=9sIK2
(final DetachedCriteria detachedCriteria, finalint NM Ajt>t
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pageSize,
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finalint startIndex){ IuF-bxA
return(PaginationSupport) B!v1gh
CHB{P\WF
getHibernateTemplate().execute(new HibernateCallback(){ BKEB,K=K@
publicObject doInHibernate %9.KH
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(Session session)throws HibernateException { `39U I7
Criteria criteria = _HQa3wj
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detachedCriteria.getExecutableCriteria(session); :O%O``xT
int totalCount = @\R)k(F
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((Integer) criteria.setProjection(Projections.rowCount Q~kwUZ
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()).uniqueResult()).intValue(); ($TxVFNT
criteria.setProjection :xV&%Qa1
4$"Lf'sH6
(null); L"a#Uu8
List items = ?*;zS%93U9
"=;&{N~8U
criteria.setFirstResult(startIndex).setMaxResults k*Kq:$9"
: Ej IV]e
(pageSize).list(); hbK+\X
PaginationSupport ps = lI 8"o>-~
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new PaginationSupport(items, totalCount, pageSize, :Us-^zVr
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startIndex); u$"5SGI6
return ps; /%7eo?@,
} u=[oo@Rk`
}, true); pLU>vQA
} S]>_o "|HV
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public List findAllByCriteria(final u+9Mc u"
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DetachedCriteria detachedCriteria){ k#.co~kS
return(List) getHibernateTemplate LHz{*`22q
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().execute(new HibernateCallback(){ weOMYJO;8
publicObject doInHibernate G-qxQD1wK
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(Session session)throws HibernateException { #E1*1E
Criteria criteria = 4)ISRR
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detachedCriteria.getExecutableCriteria(session); F-Ea85/K@4
return criteria.list(); ?9mY #_Of
} 4*3vZ6lhu
}, true); HUJ $e2[
} l>ttxYBa<d
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public int getCountByCriteria(final Q pX@;j
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DetachedCriteria detachedCriteria){ D7%89qt
Integer count = (Integer) ZUh<2F
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k
getHibernateTemplate().execute(new HibernateCallback(){ (<CLftQKg
publicObject doInHibernate TuU.yvkU
_#_Ab8#
(Session session)throws HibernateException { !EFd-fk
Criteria criteria = %(E6ADB
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detachedCriteria.getExecutableCriteria(session); =mZw71,
return L*Y}pO
tx@Q/ou`\P
criteria.setProjection(Projections.rowCount ~AO0(Lp
?`r/_EKNv
()).uniqueResult(); s0:1G
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} S("bN{7nE
}, true); S8y4 p0mV
return count.intValue(); ,wV2ZEW}e
} j% nd
} pUmB
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用户在web层构造查询条件detachedCriteria,和可选的 Jx}5`{\
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 }vi%pfrB
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PaginationSupport的实例ps。 wqyAEVea'8
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ps.getItems()得到已分页好的结果集 KpE#Ye&
ps.getIndexes()得到分页索引的数组 =4[zt^WX"
ps.getTotalCount()得到总结果数 yZ 9 *oDs
ps.getStartIndex()当前分页索引 p+t8*lkq
ps.getNextIndex()下一页索引 AL;"S;8
ps.getPreviousIndex()上一页索引 2PC4EjkC
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 'W#<8eJo
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 uJWX7UGuz
VTHDGBU
一下代码重构了。 +LyhF2
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我把原本我的做法也提供出来供大家讨论吧: kA3kh`l
^R\blJQ<^
首先,为了实现分页查询,我封装了一个Page类: &K4o8Qz
java代码: (=X16}n:>
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JDP#tA3
/*Created on 2005-4-14*/ cqq+#39iC
package org.flyware.util.page; wD<G+Y}
xs:{%ki
/** |gaZq!l
* @author Joa OS,$}I[`8
* |amEuKJ
*/ 81g&WQ'
publicclass Page { %9Ue`8
UX0tI0.tg
/** imply if the page has previous page */ xXbW6aI"
privateboolean hasPrePage; r[lHYO
pif8/e
/** imply if the page has next page */ XyI w5
9
privateboolean hasNextPage; QSLDA`
)dV.A IQ+
/** the number of every page */ :DD4BY
privateint everyPage; Nr)(&c8
}[Y):Yy
/** the total page number */ 9O)>>1}*S
privateint totalPage; 6nwO:?1o9
rfZA21y{?
/** the number of current page */ -(2-zznZ
privateint currentPage; nYe}d!
jlB3BwG{w
/** the begin index of the records by the current f8j^a?d|
0TNzVsu7
query */ &><`?
privateint beginIndex; <Du*Re6g
Fc]#\d6
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/** The default constructor */ D9Z5g3s7R
public Page(){ xq{4i|d)
w.3R1}R
} wVvU]UT
+!<`$+W
/** construct the page by everyPage (
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* @param everyPage e`oc#Od&x]
* */ p<jr&zVEc>
public Page(int everyPage){ l ghzd6
this.everyPage = everyPage; aJF`rLm
} H0HYb\TX ?
jQDxbkIuzE
/** The whole constructor */ BE2{qO{
public Page(boolean hasPrePage, boolean hasNextPage, 0(kp>%mbB
vZxy9Wmc
ovohl<o\
int everyPage, int totalPage, IF}r%%'Y$
int currentPage, int beginIndex){ 1-n0"lP~4
this.hasPrePage = hasPrePage; rQqtejcfx
this.hasNextPage = hasNextPage; dO@iq^9-
this.everyPage = everyPage; ' 4"L;){:L
this.totalPage = totalPage; <ZiO[dEV
this.currentPage = currentPage; oMPQkj;
this.beginIndex = beginIndex; :o:??tqw
} kr?|>6?
VX%+!6+fS
/** `et<Z
* @return yV. P.Q
* Returns the beginIndex. I%Awj(9BS
*/ )N/KQ[W
publicint getBeginIndex(){ >O _
return beginIndex; (tgaH,G
} e#('`vGB
v^tKT&
/** |`nVr>QF&
* @param beginIndex D4\I;M^
* The beginIndex to set. %c0;Bb-
*/ UQFuEI<1-
publicvoid setBeginIndex(int beginIndex){ ^wlep1D
this.beginIndex = beginIndex; U*@_T 3N
} }dz(DPd
<fJ\AP5
/** !xI![N^
* @return epF>z
* Returns the currentPage. JF
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*/ A@ME7^w7
publicint getCurrentPage(){ j66@E\dN
return currentPage; <G>PPf}
} *v+ fkg
<Va>5R_d<
/** \K6J{;# L
* @param currentPage S\A[Z&k0
* The currentPage to set. wu')Q/v
*/ NS q=_8
publicvoid setCurrentPage(int currentPage){ @jHio\/_
this.currentPage = currentPage; pB./L&h
} yKJ^hv"#
wk#QQDV3|0
/** l&B'.6XKs
* @return i'<1xd(`
* Returns the everyPage. R 6Em^A/>
*/ 67x^{u7
publicint getEveryPage(){ sYpogFfV
return everyPage; t3G'x1
} 0^[6
#F@7>hd1
/** 1*h7L<#|mQ
* @param everyPage k:Q<Uanc[
* The everyPage to set. vvxj{fxb)
*/ R{vPn8X6g
publicvoid setEveryPage(int everyPage){ =HHg:"
this.everyPage = everyPage; -cgukl4Va
} YqgW8EM
Dfia=1A
/** Z&,}Fgl!F
* @return =*jcO119L
* Returns the hasNextPage. -e>)yM `i
*/ Qs:r@"hE
publicboolean getHasNextPage(){ u#~!%~
return hasNextPage; :8rCCop
Uv
} =L%3q <]p
8BDL{?Mu
/** !$Z"\v'b
* @param hasNextPage 9DX3]Z\7X
* The hasNextPage to set. Sj?sw]3
*/ G>QTPXcD
publicvoid setHasNextPage(boolean hasNextPage){ VKz<7K\/
this.hasNextPage = hasNextPage; Wh5O{G@Ut
} W?-BT >#s
Ah{pidUx
/** ;4$C$r!t
* @return "6Uj:9
* Returns the hasPrePage. }3w b*,Sbz
*/ Z;D3lbqE
publicboolean getHasPrePage(){ 6a?p?I K^
return hasPrePage; (p=GR#
} vWs c{9
!`o:+Gg@
/** uFZB8+
* @param hasPrePage u V7Hsg9l
* The hasPrePage to set. ~e9INZe-j
*/ mcr#Ze
publicvoid setHasPrePage(boolean hasPrePage){ 7G/|e24
this.hasPrePage = hasPrePage; F*VMS
} Tj5@OcA$
P1 stL,
/** 4uAafQ`@H
* @return Returns the totalPage. !!%[JR)cS
* 9X9zIh]JV
*/ **w~
publicint getTotalPage(){ 2-!Mao"^
return totalPage; +|)1_NK
} } <4[(N
\N+Ta:U1P
/** wS*CcIwj
* @param totalPage ?3,tG z)
* The totalPage to set.
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*/ v9lBk]c
publicvoid setTotalPage(int totalPage){ E:=KH\2f
this.totalPage = totalPage; AO$PuzlLh
} zN/~a)
#UCQiQfP
} oV>AFs6
|!5T+H{Sj
cqL7dlhIl
3H#/u! W
:*:fun
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 }lUpC}aq_
ANQa2swM
个PageUtil,负责对Page对象进行构造: U4l*;od
java代码: =z1o}ga=EA
9$V_=Bo
uf'P9MA}>
/*Created on 2005-4-14*/ [j]J_S9jJ
package org.flyware.util.page; i z>y u[|
i2a"J&,6O
import org.apache.commons.logging.Log; RG
r'<o )
import org.apache.commons.logging.LogFactory; *a,.E6C*
pUMB)(<k
/** #IhLpO
* @author Joa V/9"Xmv75
* ,9tbu!Pvq
*/ 6Y_O^f
publicclass PageUtil { C1B3VG
gq_7_Y/
privatestaticfinal Log logger = LogFactory.getLog QC5f:BwM
GHC?Tp
(PageUtil.class); FWpN:|X BS
-C-OG}XjI
/** 1;kG[z=A
* Use the origin page to create a new page _O)2
* @param page K*U=;*p)
* @param totalRecords +>:_kE]?nX
* @return QB3d7e)8>
*/ 5 (21gW9
publicstatic Page createPage(Page page, int Q@W|GOH3
r;on0wm&B
totalRecords){ "ex~LB
return createPage(page.getEveryPage(), N[x@j)w-`
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page.getCurrentPage(), totalRecords);
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} UK~B[=b9
Fwx~ ~"I
/** 2VV[*QI
* the basic page utils not including exception HEB/\
y }&4HrT&
handler $dZ>bXUw:
* @param everyPage 3aE[F f[
* @param currentPage e8ULf~I
* @param totalRecords F;Q_*0mIQ
* @return page UC+7-y,
*/ zJuRth)(,
publicstatic Page createPage(int everyPage, int 2 ]DCF
&ap`}^8pM
currentPage, int totalRecords){ 3:~l2KIP4
everyPage = getEveryPage(everyPage); <5ft6a2fQ
currentPage = getCurrentPage(currentPage); [Zt#
c C+
int beginIndex = getBeginIndex(everyPage, I*:qGr+ WJ
I`"-$99|t1
currentPage); Ku0H?qft(
int totalPage = getTotalPage(everyPage, 3Zaq#uA
/nY).lSH
totalRecords); i{|lsd(+
boolean hasNextPage = hasNextPage(currentPage, +Y5(hjE
bQXc IIa{
totalPage); ~~xyFT+{F
boolean hasPrePage = hasPrePage(currentPage); }c35FM,
FYXw$7'l
returnnew Page(hasPrePage, hasNextPage, ^x_ >r6
everyPage, totalPage, @[5_C?2
currentPage, M$&WM{Pr^
>
h,y\uV1
beginIndex); 49xp2{
} |6sT,/6
RP~vB#}
privatestaticint getEveryPage(int everyPage){ oN[Fz a>
return everyPage == 0 ? 10 : everyPage; 1Nl&4 YLO
} \'; t*
5 Q6{(q|M
privatestaticint getCurrentPage(int currentPage){ =`]|/<=9'U
return currentPage == 0 ? 1 : currentPage; 5Cc6,
]
} g,n-s+
om".j
privatestaticint getBeginIndex(int everyPage, int nW$A^
&\"Y/b]
currentPage){ [}A_uOGEP
return(currentPage - 1) * everyPage; QmH/yy3.%
} qeQC&U
y;
IOsXPf9@
privatestaticint getTotalPage(int everyPage, int hF7V !*5
ub`z7gL
totalRecords){ :u>W&D
int totalPage = 0; `d}W;&c
VO.-.
if(totalRecords % everyPage == 0) r~Y>+ln.
totalPage = totalRecords / everyPage;
8qFUYZtY
else >vD['XN,
totalPage = totalRecords / everyPage + 1 ; <CNE>@-f
,_.@l+BM.
return totalPage; %r M-"6Q
} 9,S,NvSq
?G4iOiyt
privatestaticboolean hasPrePage(int currentPage){ F-$Z,Q]S
return currentPage == 1 ? false : true; O%YjWb
} QO5OnYh
I;Al?&uw
privatestaticboolean hasNextPage(int currentPage, V~'k1P4
-d|BO[4j
int totalPage){ Hi]vHG(
return currentPage == totalPage || totalPage == %'{V%IXQ
*oEv ,I_
0 ? false : true; H/^~<U#p
} qxf+#
,3VG.u;U
X!U]`Qh
} %:"
RzHN
=:4'
dzgs%qtK
zo_k\K`{@
k k
8R
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。 2yl6~(JC+
m5e\rMN~>\
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 Z -pyFK\
ge^!F>whr
做法如下: tW:W&|q
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象
P7}t lHX
xM% H~(
的信息,和一个结果集List: {udrT"h
java代码: ^Lsc`<xC
(3AYy0J%
d>YmKTk"
/*Created on 2005-6-13*/ x
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package com.adt.bo; nped
NV&;e[z
import java.util.List; .KFA218h*x
;rNd701p"
import org.flyware.util.page.Page; p:Iw%eZ:
NU|qX {-
/** zXQVUhL6
* @author Joa dj3|f{kg{
*/ '!pAnsXfO
publicclass Result { =ZG<BG_
XlRw Z/Wc
private Page page; cE^kpnVq|<
~ af8p {
private List content; <"N:rn{Qq
e%pu.q\gK
/** Dz,uS nnm
* The default constructor D`V6&_.p
*/ IS-}:~Pi
public Result(){ (gLea
super(); .H ,pO#{;
} GNs#oM
]F*|U`
/** /d[Mss
* The constructor using fields "Lb fF
* |B
9t-
* @param page JK[T]|G
* @param content m[8IEKo
*/ eUYZxe :6
public Result(Page page, List content){ dFzYOG1
this.page = page; g&Z"_7L~
this.content = content; vxb@9eb!H
} x,w8r+~5
|4=ihB9+
/** SK?I.
* @return Returns the content. Z?-;.G*
*/ { AFf:[G
publicList getContent(){ {JXf*IJ
return content; `4_c0q)N4
} dQ,Q+ON>
:RHm*vt
/** )W#T2Z>N1
* @return Returns the page. *E.LP1xP
*/ B4@fY
public Page getPage(){ g#w`J\iz
return page; 3eWJt\}?B
} X2LV&oi
Z A [ )
/** Cc2MYm8
* @param content I4ebkP gf
* The content to set. kY=rz&?U
*/
P`tyBe#=
public void setContent(List content){ |hc\jb
this.content = content; axtb<5&
} *-6?
M%3Wy"YQ,n
/** w#sq'vo4%
* @param page Oc#>QZ3
* The page to set. ?HV }mS[t
*/ oooS s&t
publicvoid setPage(Page page){ C\OECVT
this.page = page; p=H3Q?HJ}
} ~JLYhA^'+<
} @cPflb
a#$N% =j
!W~QT}
0t+])>
H$Kw=kMw
2. 编写业务逻辑接口,并实现它(UserManager, mzz$`M1
{tc57jsr
UserManagerImpl) S!`:E
java代码: )(lJT&e
1\y@E
9)Ly}Kzx
/*Created on 2005-7-15*/ 1 =^
package com.adt.service; /9Z!p
NZ+7p{&AN
import net.sf.hibernate.HibernateException; NCn`}QP
68p R:
import org.flyware.util.page.Page; ]
opto
$~G@
import com.adt.bo.Result; 0yaMe@&,
`w+1C&>^[
/** |kc@L`7s
* @author Joa l~D\;F
*/ e8-ehs>
publicinterface UserManager { lov%V*tL
>Mw'eQ0(y
public Result listUser(Page page)throws (-(QDRxK
`c9'0*-
HibernateException; \2 >3Opt
"Vy WT
} s&VOwU
e1UITjy
*{|$FQnR>(
:v)6gz(p
[S0mY["
java代码: *gDl~qNRoS
M*(H)i;s:w
7&foEJ3q
/*Created on 2005-7-15*/ #Kl}= 1
4
package com.adt.service.impl; ,rai%T/rL
c]NN'9G!{
import java.util.List; 3ev -Iqz
= ^s$
<
import net.sf.hibernate.HibernateException; #w|5jN?
=k_UjwgN^
import org.flyware.util.page.Page; ]-bQNYKX
import org.flyware.util.page.PageUtil; |IN[uQ
P0 b4Hq3
import com.adt.bo.Result; 1qZG`Vz
import com.adt.dao.UserDAO; |'$ l7
import com.adt.exception.ObjectNotFoundException; P,ydt
import com.adt.service.UserManager; =?/&u<
Y{+3}drJE
/** G "brT 5:
* @author Joa S3y246|4
*/ RG}}Oh="v
publicclass UserManagerImpl implements UserManager { 8wmQ4){
V;;#/$oU:4
private UserDAO userDAO; d.AC%&W
aq$q
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/** t^U^Tr
* @param userDAO The userDAO to set. 4K7{f+T
*/ M*`hDdS
publicvoid setUserDAO(UserDAO userDAO){ Dr+ Ps
this.userDAO = userDAO; #xp(B5
} (w$'o*z;(
iRt*A6`m+
/* (non-Javadoc) F#|Z# Mu
* @see com.adt.service.UserManager#listUser N2FbrfNFa
VB"(9O]
(org.flyware.util.page.Page) H1&RI4XC
*/ _ZyT3P&
public Result listUser(Page page)throws 0T9.M(
pkk4h2Ah
HibernateException, ObjectNotFoundException { -?fR|[\[U
int totalRecords = userDAO.getUserCount(); W.[BPR
if(totalRecords == 0) Y;_T=L
throw new ObjectNotFoundException ^l(^z fsZ
s)w9%
("userNotExist"); A ~&+F>Z
page = PageUtil.createPage(page, totalRecords); Z@M6!;y#
List users = userDAO.getUserByPage(page); N RSU+D-z
returnnew Result(page, users); bV6V02RF
} bVK$.*,
R=$Ls6z
} "+h/-2rA
%l|\of7P2}
#>[wD#XJV
G~!C=l
l$M +.GB<
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 AC4 l<:Yh
bEI!Ja
询,接下来编写UserDAO的代码: U^ ?=
0+
3. UserDAO 和 UserDAOImpl: (U9a@1
java代码: 3U;1D2"AE
e U;jP]FA
Y/lN@
/*Created on 2005-7-15*/ :Q-F9o
J
package com.adt.dao; {Hk/1KG>
0roCP=;
import java.util.List;
] .5OX84
- _t&+5]
import org.flyware.util.page.Page; WQKj]:qk0
ZqK]jT6V/X
import net.sf.hibernate.HibernateException; AP w6
`{}@@]
/** ( 3;`bvYH"
* @author Joa (oYW]c}G,
*/ \_U*t!
publicinterface UserDAO extends BaseDAO { *Hunp Y
JXm?2/
publicList getUserByName(String name)throws XA3s],Rk
SdI1}&
HibernateException; w~N-W8xNR
_]o5R7[MQ
publicint getUserCount()throws HibernateException; X4Xf2aXI
o5 WW{)Q
publicList getUserByPage(Page page)throws hk;bk?:m
784;]wdy\
HibernateException;
TQ' e
:Tb7r6
} w1i?#!|
Euu
,mleM
#T"64%dX
plXG[1;&G
}cW#045es
java代码: [H^ X"D
x+^Vg3 q
N-QCfDao
/*Created on 2005-7-15*/ %U?)?iZdL
package com.adt.dao.impl; @?a4i
CQ> ]jQ,2
import java.util.List; O<X
)p`,`
.bfST.OA
import org.flyware.util.page.Page; 3;Hd2 ;G
]^'ZiyJX
import net.sf.hibernate.HibernateException; >{XScxaB`
import net.sf.hibernate.Query; J]\^QMX
o4~kX
import com.adt.dao.UserDAO; /qXzOd
f_'"KF[%
/** all*P #[X
* @author Joa %?dE{ir
*/ <Uwwux<v
public class UserDAOImpl extends BaseDAOHibernateImpl c F=P!2@
!*bdG(pK
implements UserDAO { a8QfkOe
bA*"ei+!
/* (non-Javadoc) 5/(sjMB
* @see com.adt.dao.UserDAO#getUserByName 4 Py3I9
sam[s4@eQ
(java.lang.String) !I7 ?
*/ })7K S?
publicList getUserByName(String name)throws 61,O%lV
kfK[u/<i
HibernateException { FG#nap{
String querySentence = "FROM user in class ,qu:<
w4A#>;Qu*
com.adt.po.User WHERE user.name=:name"; `^e*T'UPl
Query query = getSession().createQuery y5%5O xB
}4KW@L[g
(querySentence); 9b%j.Q-W
query.setParameter("name", name); ?i%nMlcc
return query.list(); /.@x
4cdS
} #ovM(Mld
t=
*Jg/$
/* (non-Javadoc) :D4];d>1
* @see com.adt.dao.UserDAO#getUserCount() PW)8aLU
*/ pN+I]NgQ
publicint getUserCount()throws HibernateException { # JFYws
int count = 0; TrQm]9 @
String querySentence = "SELECT count(*) FROM ~'{VaYk]v
}5hZo%w[n
user in class com.adt.po.User"; dk:xnX%
Query query = getSession().createQuery Om6Mmoqh
2-7Z(7G{ F
(querySentence); 5"uNj<.V
count = ((Integer)query.iterate().next RNe9h lr
-R8/`M8GbD
()).intValue(); s9 &)Fv-#V
return count; FE}s#n_Pd
} b~9`]+
/+29.1#|
/* (non-Javadoc) q|Fjm]AF
* @see com.adt.dao.UserDAO#getUserByPage MYu`c[$jZ
Iht'e8)gq
(org.flyware.util.page.Page) J@gm@ jLc
*/ 1q`k}KMy
publicList getUserByPage(Page page)throws SdSgn |S
AHWh}~Yi
HibernateException { *?p
^6vO
String querySentence = "FROM user in class =-m(\}
6+?wnp-
com.adt.po.User"; H7}g!n?
Query query = getSession().createQuery ~W3:xnBEk
l-cW;b~
(querySentence); 8XlU%a6x
query.setFirstResult(page.getBeginIndex()) X*)?LxTj
.setMaxResults(page.getEveryPage()); 9u?Eb~#$
return query.list(); |+u+)C
} T:6K?$y?
%fBP:5%K
} e|JIrOnc
TqXge{r
PY2[S[
dDo6fP2
_TrZ'iL}T
至此,一个完整的分页程序完成。前台的只需要调用 7MoR9,(
5
>'66gZ
userManager.listUser(page)即可得到一个Page对象和结果集对象 gU+ss
~z &0qQ
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*L^^%w
tg3zXJ4k_
webwork,甚至可以直接在配置文件中指定。 pL8H8kn
'!AT
下面给出一个webwork调用示例: 2G
ZF/9}
java代码: $,.3&zsy
4Q@\h=r
e~3]/BL
/*Created on 2005-6-17*/ 40R"^*
package com.adt.action.user; s:3aRQ%
Qg[heND
import java.util.List; }M^_Z#|,
1E8$% 6VV
import org.apache.commons.logging.Log; *B%y`cj|
import org.apache.commons.logging.LogFactory; ) sRN!~
import org.flyware.util.page.Page; ^)Smv\Md
7,f:Qi@g
import com.adt.bo.Result; !;TR2Zcn
import com.adt.service.UserService; `(P
"u
import com.opensymphony.xwork.Action; )ni"qv~J
o1Ne+Jt
/** PL9<*.U"=
* @author Joa K4_~ruhr
*/ EN)YoVk
publicclass ListUser implementsAction{ U[IQ1AEr
Ih(:HFRMq6
privatestaticfinal Log logger = LogFactory.getLog :2 _0L
Ob7zu"zr
(ListUser.class); _cR6ik zW(
#,t2*tM
private UserService userService; K1/
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(A
I+*osk
private Page page; BQ).`f";d
"&@gX_%
privateList users; xT:qe
4tbw*H5!5
/* ;9}w|!/
* (non-Javadoc) ]U_5\$
* T:be 9 5!,
* @see com.opensymphony.xwork.Action#execute() 3Wjq >\
*/ Ti hnSb
publicString execute()throwsException{ 4s[`yV
Result result = userService.listUser(page); "(Mvl1^BT
page = result.getPage(); o^8*aH)I>Y
users = result.getContent(); Jw2B&)k/
return SUCCESS; yZ?xt'tn
} d#E(~t(^
?$UH9T9)
/** =s`XZkh
* @return Returns the page. AqKHjCI
*/ NKRaQr
public Page getPage(){ qsD?dHi7
return page; VEL:JsY
} \El|U#$u'
d&/^34gn
/** TFAYVK~
* @return Returns the users. ~C%2t{"
*/ PthIdaN@
publicList getUsers(){ R1II k
return users; U*
-% M
} Tm(Q@
FgXu1-
/** _cW_u?0X:
* @param page t.3Ct@wK
* The page to set. <FCj)CP%
*/ l\q*%'Pe
publicvoid setPage(Page page){ OAmES;Ck$(
this.page = page; r~8D\_=s
} pem3G5
`g=
'CP/ym f/a
/** 9V|E1-")E
* @param users LXBbz;vYl
* The users to set. uPa/,"p
*/ v[0DE*p
publicvoid setUsers(List users){ s-QM6*
this.users = users; {Q{lb(6Ba
} )2iM<-uB
Xz;et>UD*B
/** -9=M9}eDF
* @param userService CBiU#h
q
* The userService to set. >wz;}9v
*/ {DKXn`V
publicvoid setUserService(UserService userService){ @5{.K/s
this.userService = userService; 4yA9Ni
} 7Vz[ji
} 08TaFzP81
Z7tU0
Q'n(^tbL
[VY8?y
:z0s*,QH
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, 71oFm1m{
dzjB UD
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 ib5;f0Qa
6{JR 0
么只需要: 3v8V*48B$
java代码: MgJ%26TZ
y3
({(URU
Uq<a22t@
<?xml version="1.0"?> =]_d pE EQ
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 6vD]@AF
k| _$R?
1.0//EN" "http://www.opensymphony.com/xwork/xwork- *G%1_
\_*?R,$3Y,
1.0.dtd"> 1g~Dm}m
bE7(L
$UF
<xwork> n/9 LRZD|w
jMm_A#V>p
<package name="user" extends="webwork- Ns+)Y^(5
^4xlZouCb
interceptors"> SR&(HH$
R9b/?*%=9
<!-- The default interceptor stack name }<(
"0jC
@{J!6YGh
--> "e1{V8
4
<default-interceptor-ref |'V<>v.v
JfZL?D{NM
name="myDefaultWebStack"/> aGq_hP
E%wV
<action name="listUser" 8]cv &d1f
<3SFP3^:
class="com.adt.action.user.ListUser"> _ 6+,R
<param "4Vi=* 2V
WrE-Zti
name="page.everyPage">10</param> ]t.WJC %
<result w%i+>\tO
u%+6Mp[E
name="success">/user/user_list.jsp</result> [OFTP#}c
</action> Xm"w,J&
'Yaf\Hp
</package> JEK%yMj
Jf%!I
</xwork> 2- Npw%;
p?Z+z
;w>3,ub(0
hQg,#r(JE4
~cO?S2!W
+BtLyQ
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 %KabyvOl)
/?.r!Cp
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。 mC{!8WC@k
dyQ<UT
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 |!4BWt
z. _C*c
c"f-$^<
2g ?Jb5)
vc>^.#7
我写的一个用于分页的类,用了泛型了,hoho q_9N+-?{7
+H)!uLvaB
java代码: UZ4tq
N8DiEB3~
/H\^l.|vk
package com.intokr.util; %mB!|'K%
n3HCd-z
import java.util.List; ((RpT0rP\
o5*74Mv
/** GM9]>"#o\
* 用于分页的类<br> Pjj;.c 7_j
* 可以用于传递查询的结果也可以用于传送查询的参数<br> JhMrm%
* 3IU$
* @version 0.01 0btmao-
* @author cheng oSu|Yn
*/ .swgXiRvs
public class Paginator<E> { >n$EeJ
privateint count = 0; // 总记录数 , IMT '*
privateint p = 1; // 页编号 G(7\<x:
privateint num = 20; // 每页的记录数 (zM+7tJH
privateList<E> results = null; // 结果 #RLch
NSiYUAug
/**
eo<~1w
* 结果总数 vZ_DG}n11
*/ *mK);@pL
publicint getCount(){ 5JU(@}Db
return count; R
uFu,H-
} %Zl_{Q]h
st'?3A
publicvoid setCount(int count){ 654jS!
this.count = count; 0-t4+T
} R+ #.bQg
)K\k6HC.
/** QX.F1T2e?
* 本结果所在的页码,从1开始 Be14$7r
* eLt Cxe
* @return Returns the pageNo. <2TB9]2. g
*/ *]>OCGsr
publicint getP(){ 4Ow
Vt&
return p; 0\_R|i_`>
} e~2*>5\:
N?U&(@p
/** +}G>M=t::
* if(p<=0) p=1 *{;A\sL
* 2fL88/'
* @param p G.q^Zd#.T
*/ /xrq'|r?C
publicvoid setP(int p){ !Pi?
!
if(p <= 0) L/ICFa.G
p = 1; n4r( Vg1GS
this.p = p; whg4o|p
} ["#A -S
z7l;|T
/** Kz*AzB
* 每页记录数量 }~\].I6
*/ {;z
L[AgCg
publicint getNum(){ {</$ObK
return num; $RFu
m'`5
} GE3U0w6WbK
cwW~ *90#
/** ?BWvF]p5/
* if(num<1) num=1 tgF(=a]o
*/ S>ylA U;N
publicvoid setNum(int num){ :#&U95EC0
if(num < 1) %ucmJ-<y#
num = 1; o j4)7{
this.num = num; koWb@V]
} [Ey%uh
6*
A'AWuj\r2R
/** >0;"qT
* 获得总页数 ? Ge*~d
*/ K/.hJ
publicint getPageNum(){ MIyLQ
return(count - 1) / num + 1; gZ=9Y:$
} {ZIFj.2
_ L:w;Oy9T
/** Xi`U`7?D(=
* 获得本页的开始编号,为 (p-1)*num+1 `_{'?II
*/ (XIq?c1T
publicint getStart(){ Sdu@!<?B
return(p - 1) * num + 1; Ew,wNR`
} !
{o+B^^
h}:5hi Jw
/** ?yM/j7Xn
* @return Returns the results. 7Caap/L:
*/ E~O>m8hF
publicList<E> getResults(){ xg5@;p
return results; .j<B5/+
} @/2wmza%2
czsoD)N
public void setResults(List<E> results){ Gt%?[
this.results = results; tlxjs]{0E
} 8RT0&[
FEi,^V
public String toString(){ Y&Vbf>Hi+
StringBuilder buff = new StringBuilder 7Hlh
(k
K[;,/:Y
(); r_<i*l.
buff.append("{"); sL`D}_:
buff.append("count:").append(count); C%o/
buff.append(",p:").append(p); p`.fYW:p
buff.append(",nump:").append(num); kX .1#%Ex
buff.append(",results:").append 7ofH@U
;A'17B8
(results); =xWW+w!r
buff.append("}"); SSM>
ID
return buff.toString(); "uERa(i
} `e;Sjf<
;}9Ws6#XQs
} EBE>&{%$^
_q4dgi z
_^sSI<&m