Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 "+_]N9%)
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Cd'P
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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 pPo?5s
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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 -_uL;9r
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分页支持类: P:lvZ
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java代码: Vnh
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package com.javaeye.common.util; oCy52Bm.!
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import java.util.List; [7<X&Q
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publicclass PaginationSupport { ,z1# |Y
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publicfinalstaticint PAGESIZE = 30; N#7 ]xL
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privateint pageSize = PAGESIZE; O b8[P=
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privateList items; #H!~:Xu
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privateint totalCount; K"}Dbr
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privateint[] indexes = newint[0]; jb7=1OPD_
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privateint startIndex = 0; o8s&n3mY}y
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public PaginationSupport(List items, int AP@xZ%;K
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totalCount){ cU{LyZp
setPageSize(PAGESIZE); ..~{cU4Tt
setTotalCount(totalCount); _I8-0DnOM
setItems(items); 5Q%#Z
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setStartIndex(0); BbU&e z8P
} e<p$Op
xDQ$Ui.
public PaginationSupport(List items, int I7uYsjh@u
Z(<ul<?r
totalCount, int startIndex){ D>|:f-Z6Z
setPageSize(PAGESIZE); 5vpf;
setTotalCount(totalCount); 1B1d>V$*
setItems(items); #-@{ rgH
setStartIndex(startIndex); IK W!P1
} C$tSsw?A
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public PaginationSupport(List items, int c^bA]l^a
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totalCount, int pageSize, int startIndex){ \;?\@vo<
setPageSize(pageSize); JNu - z:J
setTotalCount(totalCount); r]E$uq
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setItems(items); %b*%'#iK
setStartIndex(startIndex); S1+#qs{5a
} S:}s |![p
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publicList getItems(){ JxvwquI
return items; [qXpi'q[
}
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publicvoid setItems(List items){ GmHsO/
this.items = items; nY8UJy}<oL
} |4c==7.
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publicint getPageSize(){ 7*5ctc!dG
return pageSize; ~mp$P+M(%p
} iWCV(!
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publicvoid setPageSize(int pageSize){ Z`*cI
this.pageSize = pageSize; <oO,CXF
} |]q=D1/A
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publicint getTotalCount(){ [v`4OQF/
return totalCount; ;1dz?'%V
} ]M2<I#hF.
Lm?*p>\Q
publicvoid setTotalCount(int totalCount){ yRYWx` G
if(totalCount > 0){ lkm(3y@']A
this.totalCount = totalCount; R\}YD*
int count = totalCount / ^55?VQB
2{CSH_"Z7
pageSize; (*ng$zZ$
if(totalCount % pageSize > 0) !7oy%{L
count++;
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indexes = newint[count]; MT`gr
for(int i = 0; i < count; i++){ gp HwiFc
indexes = pageSize * %Let AR
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i; wDO5Zew!
} !d\GD8|4
}else{ 3\+p1f4
this.totalCount = 0; $at|1+bQ
} YZl%JX
} }^[@m#
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publicint[] getIndexes(){ [QbXj0en$
return indexes; 3(+#^aw
} Hz8`)cv`
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publicvoid setIndexes(int[] indexes){ =on!&M
this.indexes = indexes; N| Pm|w*?
} l7,qWSsnK
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publicint getStartIndex(){ 1fv~r@6s
return startIndex; J~3T8e#
} _|3TC1N$n
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publicvoid setStartIndex(int startIndex){ %:KV2GP
if(totalCount <= 0) %D(prA_w
this.startIndex = 0; ZT8Ji?_n
elseif(startIndex >= totalCount) e[mhbFf-
this.startIndex = indexes >JPJ%~y
Ln2C#Uf
[indexes.length - 1]; otf%kG w
elseif(startIndex < 0) noNF;zT
this.startIndex = 0; ?vn 0%e868
else{ ZT"|o\G^Q
this.startIndex = indexes H
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[startIndex / pageSize]; ; [%}Xx
} #oJbrh9J6
} xPMyG);
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publicint getNextIndex(){ =j+oKGkoCa
int nextIndex = getStartIndex() + h2"|tTm,a
xSDE6]
pageSize; Uc_`Eh3y
if(nextIndex >= totalCount) &lPBqw
return getStartIndex(); =HV-8C]
else xcZ%,7
return nextIndex; )xvx6?Ah|
} SXBQ
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publicint getPreviousIndex(){ R_>TEYZ
int previousIndex = getStartIndex() - HM@}!6/s
RUk<=!U
pageSize; Qw<kX*fxrI
if(previousIndex < 0) +# RlX3P
return0; L_U3*#Zdz7
else 2&gVZ z
return previousIndex; 7"n1it[RJ8
} u1;e*ty
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} yF/< :
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抽象业务类 D]pK=247
java代码: YMj7
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/** &ppE|[{
* Created on 2005-7-12 KkdG.c'
*/ jMf 7J
package com.javaeye.common.business; cXb
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import java.io.Serializable; z;bH<cQ
import java.util.List; xm}q6>jRV
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import org.hibernate.Criteria; 28T\@zi
import org.hibernate.HibernateException; *Z]5!$UpC
import org.hibernate.Session; z*M}=`M$
import org.hibernate.criterion.DetachedCriteria; O1x0[sy
import org.hibernate.criterion.Projections; $[M}K
import ><;l:RGK|
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org.springframework.orm.hibernate3.HibernateCallback; |D;_:x9
import L4YVH2`0)
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org.springframework.orm.hibernate3.support.HibernateDaoS gdoJ4b
&mh Ln4^
upport; ]s*5[=uc2
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import com.javaeye.common.util.PaginationSupport; kRmj"9oA
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public abstract class AbstractManager extends +?qf`p.{
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HibernateDaoSupport { =y?#^
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privateboolean cacheQueries = false; OI~}e,[2z
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privateString queryCacheRegion; ? ouV
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publicvoid setCacheQueries(boolean 'b8R#R\P
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cacheQueries){ q#;BhPc
this.cacheQueries = cacheQueries; <\h*Zy
} {5SfE$r
]} '^`
publicvoid setQueryCacheRegion(String Ymq3ty]Pe
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queryCacheRegion){ "hW(S
this.queryCacheRegion = ;vMn/
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queryCacheRegion; x7f:F.
} USprsaj
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publicvoid save(finalObject entity){ QW2?n`Fa9-
getHibernateTemplate().save(entity); n<E.Em1
} UIn^_}jF`
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publicvoid persist(finalObject entity){ ~]4kkm7Y
getHibernateTemplate().save(entity); !#. \QU|
} )Lb72;!?
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publicvoid update(finalObject entity){ aRX
getHibernateTemplate().update(entity); |ixGY^3;
} $R";
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publicvoid delete(finalObject entity){ _e_4Q)z-a
getHibernateTemplate().delete(entity); JPsSw
} i *B:El1
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publicObject load(finalClass entity, Yq
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finalSerializable id){ uWTN2jr
return getHibernateTemplate().load %[XY67A3I
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(entity, id); l~['[Ub0)
} !y%+GwoW
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publicObject get(finalClass entity, { V0>iN:~S
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finalSerializable id){ T/5"}P`
return getHibernateTemplate().get {y b D
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(entity, id); HlPG3LD!
} (f~gEKcB2u
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publicList findAll(finalClass entity){ 7@IFp~6<qK
return getHibernateTemplate().find("from s^cc@C
%[ /<+
" + entity.getName()); ~:EW>Fq%i
} \?&Au
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publicList findByNamedQuery(finalString B+Z13;}B
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namedQuery){ q^*6C[G B
return getHibernateTemplate ej52AK7
.*!#98pT
().findByNamedQuery(namedQuery); Sl>>SP
} M6Pw/S!
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publicList findByNamedQuery(finalString query, CZ3].DA|z
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finalObject parameter){ aD ESr?
return getHibernateTemplate /.$L"u
iCrxV{
().findByNamedQuery(query, parameter); sx5r(0Z
} DMd ,8W7a
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publicList findByNamedQuery(finalString query, JMlV@t7y<
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finalObject[] parameters){ +.@c{5J<
return getHibernateTemplate }+0z,s~0.
!;dSC<
().findByNamedQuery(query, parameters); AmcC:5
} wqy^8N[K]
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publicList find(finalString query){ |pW\Ec#(
return getHibernateTemplate().find .Xd0
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(query); )X5(#E
} XP?*=Z]
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publicList find(finalString query, finalObject \c7>:DH
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parameter){ V1utUGJV
return getHibernateTemplate().find d?hz LX
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(query, parameter); \%5MAQS
} AhxGj+
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public PaginationSupport findPageByCriteria GGnp Pp
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(final DetachedCriteria detachedCriteria){ uLV BM]Qj
return findPageByCriteria !wh&>3~
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); NK/4OAt%
} M"wue*&
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public PaginationSupport findPageByCriteria ::"E?CQLV
*H2]H@QHN
(final DetachedCriteria detachedCriteria, finalint &mkpJF/
/fwgqFVk
startIndex){ A';QuWdT
return findPageByCriteria \:&@;!a
,]$A\+m'
(detachedCriteria, PaginationSupport.PAGESIZE, o""~jc~
|4C^$
startIndex); !'W- 6f
} kGHC]Fb)
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public PaginationSupport findPageByCriteria ^^}Hs-{T
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(final DetachedCriteria detachedCriteria, finalint flnVYQe
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pageSize, ?[TW<Yx
finalint startIndex){ #n7Yr,|Z
return(PaginationSupport) x$B&L`QV
tZ8e`r*
getHibernateTemplate().execute(new HibernateCallback(){ 4v.d-^
publicObject doInHibernate IXq(jhm8bL
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(Session session)throws HibernateException { N|dD!
Criteria criteria = GYK\LHCPd
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detachedCriteria.getExecutableCriteria(session); O<N#M{kc.
int totalCount = w^;DG
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((Integer) criteria.setProjection(Projections.rowCount @d&H]5
o8S"&O
?
()).uniqueResult()).intValue(); 2@Lbfo A
criteria.setProjection \}dyS8
*'8Ln tZf
(null); v 1+U;Th>g
List items = f_\_9o"l
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criteria.setFirstResult(startIndex).setMaxResults ;YH[G;aJ
&Lj@9\Dh
(pageSize).list(); Z4q~@|+%
PaginationSupport ps = 6"QEJ
r>n"
51*
new PaginationSupport(items, totalCount, pageSize, \N6\v5vh
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startIndex); `
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return ps; 0A[e sWmP
} gv.6h{Ut
}, true); 63&^BW
} <$i4?)f(
7y<1LQ;}
public List findAllByCriteria(final ^mPPyT ,(
7"2b H
DetachedCriteria detachedCriteria){ vq'k|_Qi=
return(List) getHibernateTemplate #h'@5 l
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().execute(new HibernateCallback(){ P3o@g kXP
publicObject doInHibernate WeJ@xL
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(Session session)throws HibernateException { ^DAu5 |--R
Criteria criteria = PuCc2'#
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detachedCriteria.getExecutableCriteria(session); B6M+mx"G
return criteria.list(); 7+,vTsCd
} gK1g]Tc @G
}, true); EbK0j?
} wNWka7P*
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public int getCountByCriteria(final k&6I f0i
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DetachedCriteria detachedCriteria){ +wfVL|.Wq
Integer count = (Integer) T0QvnIaP
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getHibernateTemplate().execute(new HibernateCallback(){ uofr8oL~
publicObject doInHibernate K~6e5D7.
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(Session session)throws HibernateException { OI/@3"L{
Criteria criteria = q9*MNHg}
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detachedCriteria.getExecutableCriteria(session); QWO]`q`|
return Va<eusl
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criteria.setProjection(Projections.rowCount x4kWLy7Sz
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()).uniqueResult(); a\5FAkI
} 3=.Y,ENM;
}, true);
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return count.intValue(); Wch~Yb
} 9U_ks[Qa
} eEw.'B
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用户在web层构造查询条件detachedCriteria,和可选的 _Xcn
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 '])2k@o@
{No L
PaginationSupport的实例ps。 d@C&+#QDF
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ps.getItems()得到已分页好的结果集 p>=[-(mt
ps.getIndexes()得到分页索引的数组 B@YyQ'
ps.getTotalCount()得到总结果数 }G <T :(a
ps.getStartIndex()当前分页索引 P(k(m<0
ps.getNextIndex()下一页索引 yL4 T
ps.getPreviousIndex()上一页索引 zvc`3
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 4674SzL
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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 lfsqC};#\
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一下代码重构了。 M6r^L6$N
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我把原本我的做法也提供出来供大家讨论吧: s
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A=zPLq{Sb
首先,为了实现分页查询,我封装了一个Page类: <Peebv&v
java代码: FbnO/! $8
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/*Created on 2005-4-14*/ hG~reVNf
package org.flyware.util.page; #3=P4FUz.
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/** }ov&.,vQ
* @author Joa q-ES6R
* |tzg:T;
*/ 1{Mcs%W;w5
publicclass Page { i JxQB\x
g$:Xuw1
/** imply if the page has previous page */ @XD+' {]
privateboolean hasPrePage; ^[-el=oKn0
NC qo@vE
/** imply if the page has next page */ l%z< (L5
privateboolean hasNextPage; 4n1; Bh$
IPSF]"}~
/** the number of every page */ E@05e
privateint everyPage; P #F=c34u
{j {+0V
/** the total page number */ |sZ!
privateint totalPage; t%zpNd2lk
1T_QX9
/** the number of current page */ )Dp/('Z2
privateint currentPage; R.[Z]-X
j6~nE'sQ
/** the begin index of the records by the current "TV(H+1,z
rdnno
query */ XS0xLt=
privateint beginIndex; Ed0I WPx
@\oz4^
dLsn\m>
/** The default constructor */ b96%")
public Page(){ "xMD,}+5$$
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} p2J|Hl|
6+V\t+aug
/** construct the page by everyPage M'`;{^<
* @param everyPage Zn,>]X
* */ PN~@
public Page(int everyPage){ }pkj:NT
this.everyPage = everyPage; 'sp-%YlM -
} ,y9iKkg
/!}'t
/** The whole constructor */ ]Ni$.@Hu$
public Page(boolean hasPrePage, boolean hasNextPage,
O=)
S1 _6C:^k
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int everyPage, int totalPage, G>YAJo
int currentPage, int beginIndex){ <?D[9Mk$
this.hasPrePage = hasPrePage; VN4yn| f/
this.hasNextPage = hasNextPage; o!Ev;'D
this.everyPage = everyPage; dX8hpQ
this.totalPage = totalPage; m`4R]L]
this.currentPage = currentPage; p
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this.beginIndex = beginIndex; 9p$V)qdX
} TGuiNobD
,=(Z00#(
/** Q@e[5RA+]
* @return n[Zz]IO,g
* Returns the beginIndex. K|C^l;M6
*/ %xwIt~Y
publicint getBeginIndex(){ WWwUwUi
return beginIndex; =k}SD96
} }}QT HR
a m-b!l!q^
/** 2:}fe}
* @param beginIndex vgn@d,v
* The beginIndex to set. UX`]k{Mz
*/ rdJm{<
publicvoid setBeginIndex(int beginIndex){ GZ!|}$8
this.beginIndex = beginIndex; k)S.]!u&G
} Jxf~&!zR
uBg 8h{>
/** ^/wfXm
* @return R8*Q$rH<
* Returns the currentPage. QVZD/shq
*/ ?[ly`>KpJ
publicint getCurrentPage(){ B bhfG64
return currentPage; W-RqN!snJ8
} \u`)kJ5o1
+i `*lBup$
/** jD){I
* @param currentPage [\)oo
* The currentPage to set. IC/(R! Crj
*/ < V\Y@Ei+
publicvoid setCurrentPage(int currentPage){ >-T`0wI
this.currentPage = currentPage; \^+ILYO:$
} Y izE5[*
t^=U*~
/** O|kKwadC
* @return u#W5`sl
* Returns the everyPage. TL= YQA
*/ Eu@5L9A
publicint getEveryPage(){ <Pqv;WI|R
return everyPage; h>S[^
-,
} @z6!a
~ <0Z>qr
/** `Y?t@dd
* @param everyPage $KV&\Q3\0
* The everyPage to set. xtV[p4U
*/ "yb WDWu
publicvoid setEveryPage(int everyPage){ *a}(6Cx
this.everyPage = everyPage; +,'T=Ic{
} `cP <}^]
S^RUw
/** r >{G`de4
* @return v vu<:16
* Returns the hasNextPage. A(6xg)_XQ
*/ BWPP5X9
publicboolean getHasNextPage(){ O0l^*nZ46t
return hasNextPage; rp!
LP#*
} ;#?M)o:q
Ry;$^.7%
/** JXQPT
* @param hasNextPage ;|ub!z9GG
* The hasNextPage to set. U)jUq_LX
*/ %Tcf6cK"
publicvoid setHasNextPage(boolean hasNextPage){ PB'0?b}fab
this.hasNextPage = hasNextPage; mL L$|
} </oY4$ l'
B:oF;~d/,
/** ,cHU) j
* @return .CV _\
* Returns the hasPrePage. tiQ;#p7%
*/ I=dGq;Jaz
publicboolean getHasPrePage(){ e$l6gY
return hasPrePage; +H'\3^C-
} WO</Q6+
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/** ?T*";_o,B
* @param hasPrePage d+2daKi
* The hasPrePage to set. I lG:X)V%
*/ @ RR\lZ
publicvoid setHasPrePage(boolean hasPrePage){ <)#kq1b?
this.hasPrePage = hasPrePage; -WR}m6yMr
} QXQ
,+L
KJl
/** 2"/yEg*=
* @return Returns the totalPage. `.BR=['O
* T!^Mvat
*/ ZlR!s!vv
publicint getTotalPage(){ womq^h6
return totalPage; 4,}GyVJFb`
} I-:`cON=G
y4F^|kS) [
/** #ooc)),
* @param totalPage &hN,xpC
* The totalPage to set. !WKk=ysFS
*/ U"5q;9#q
publicvoid setTotalPage(int totalPage){ km>o7V&4G
this.totalPage = totalPage; @-6?i)
} \iZ1W
'Z[d7P
} \Hum }0[
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Z{}+)Q*Q
#v8Cy|I
BX$hAQ(6Q
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 `^%GN8d}nm
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个PageUtil,负责对Page对象进行构造: Bcm=G""
java代码: 7eH@n<]Y2
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/*Created on 2005-4-14*/ <M>#qd@c
package org.flyware.util.page; n(# c`t*
c$.T<r)Z
import org.apache.commons.logging.Log; 2c*2\93>
import org.apache.commons.logging.LogFactory; Xa\]ua_
h!;MBn`8
/** &:,fb]p
* @author Joa $pJ3xp&
* _4S7wOq5
*/ n%Rjt!9
publicclass PageUtil { Ut=0~x.=<
)S"o{N3B
privatestaticfinal Log logger = LogFactory.getLog c'[( d5^|
gGD]t;<u
(PageUtil.class); _c,&\ wl$
/XC;.dLA#
/** ek.WuOs
* Use the origin page to create a new page A>1p]#
* @param page j7HlvoZV
* @param totalRecords ))+98iU1s
* @return =rO>b{,hs
*/ 8KELN(o$ 7
publicstatic Page createPage(Page page, int CnA)>4E*'
nW*Oo|p~=
totalRecords){ HD|)D5wH|
return createPage(page.getEveryPage(), 'E8Qi'g
6x8|v7cMH
page.getCurrentPage(), totalRecords); #T`+~tW'|
} l Nt o9
n}kz&,
/** ?y@pRe$2
* the basic page utils not including exception qiJ{X{lI
YZ
P
handler ..mz!:Zs0
* @param everyPage - & r{%7
* @param currentPage @6`@.iZ
* @param totalRecords pz =Wq4l
* @return page 7^X_tQf
*/ B6&Mtm1
publicstatic Page createPage(int everyPage, int t4uxon
_%!hkc(
currentPage, int totalRecords){ AOUO',v
everyPage = getEveryPage(everyPage); )UeG2dXx7
currentPage = getCurrentPage(currentPage); C"}x=cK
int beginIndex = getBeginIndex(everyPage, ATU@5,9
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currentPage); `C1LR,J
int totalPage = getTotalPage(everyPage, L%DL
n
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totalRecords); +38t82%YWo
boolean hasNextPage = hasNextPage(currentPage, &
2bf
><=af 9T
totalPage); X}ZOjX!
boolean hasPrePage = hasPrePage(currentPage); W)l&4#__(
)D^P~2
returnnew Page(hasPrePage, hasNextPage, _eF*8 /z
everyPage, totalPage, (mEZ4yM
currentPage, +SJ aE] $
#yqcUbJY0R
beginIndex); Hq~ 2,#Ue
} FR <wp
I}:/v$btM
privatestaticint getEveryPage(int everyPage){ 9.R_=
return everyPage == 0 ? 10 : everyPage; M_e!s}F
} aZ'p:9e
OJ 2M_q)e
privatestaticint getCurrentPage(int currentPage){ dug RO[
return currentPage == 0 ? 1 : currentPage; 4e:hKv,+4
} Wj3H
y4
6QV/8IX
privatestaticint getBeginIndex(int everyPage, int /oI''O%M
~2qFA2
currentPage){ e0qa~5
return(currentPage - 1) * everyPage; hk=+t&Y<H
} D H/1 :H
j04Q3d
\f
privatestaticint getTotalPage(int everyPage, int XH. _Z
eI[z%j[Y*
totalRecords){ v|hi;l@7E
int totalPage = 0; jJf|Ok:G{
\h
yTcFb
if(totalRecords % everyPage == 0) t^YDCcvoQ
totalPage = totalRecords / everyPage; Vf:t!'WD?2
else !=-l760
totalPage = totalRecords / everyPage + 1 ; WgjaMmht
IL~yJx_11
return totalPage; M,9WF)p)V
} %jkd}D
7W>T=
@
privatestaticboolean hasPrePage(int currentPage){ 55AG>j&41
return currentPage == 1 ? false : true; |[qI2-e l?
} Fb_~{q
P}PSS#nn
privatestaticboolean hasNextPage(int currentPage, ^c2 8Q.<w(
fN&O `T>
int totalPage){ UVUHLu|^
return currentPage == totalPage || totalPage == # ><.zZ
fpzTv3D=I
0 ? false : true; Um|:AT}`^
} 8g$ 8]'M^T
\'p)kDf
Z8:iaP)
} UgUW4x'+
yn7n
.Wr7?'D1M
vg)zk2O
3Y=S^*ztd
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。
:&Ul
JY /Cd6\
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 u2DsjaL
F'Wef11Yz
做法如下: <|.M]]}j
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 j\W+wnAgk
o`&idn|,
的信息,和一个结果集List: Sd{>(YWx~
java代码: =n;ileGm+^
5:YtBdP
+pDuRr
/*Created on 2005-6-13*/ DTJ~.
package com.adt.bo; =!p6}5Z
Ao0F? 2|
import java.util.List; u[cbRn,W
YHE7`\l
import org.flyware.util.page.Page; p[W8XX
N<?RN;M
/** }B"kJNxV
* @author Joa u<):gI
*/ (/Nw
publicclass Result { ZY{,//
f^ nogw<z!
private Page page; Vj`9j. 5
B:Msn)C~
private List content; _<xU"8b"5
lQ@2s[
/** IspY%UMl
* The default constructor /EWF0XV!
*/ M)Y`u
public Result(){ W4T>@b.
super(); '|Cs!Zl
} z%]~^k8
UiW(/L
/** bp;)*
* The constructor using fields qksN {t
* mM>{^%2Q:
* @param page lO)p
* @param content <+C]^*j
*/ NNS n]LP
public Result(Page page, List content){ ~[l2"@
this.page = page; BpRQG]L
this.content = content; 4RJ8 2yq-
} 7a->"W
e}-uU7O
/** v$owG-_><
* @return Returns the content. --dGN.*xb4
*/ gh['T,
publicList getContent(){ sbQmPV
return content; KAO}*?
} -P!vCf^{
t
%]nLCoQh
/** uZW
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* @return Returns the page. 4qrPAt
*/ AuX&
public Page getPage(){ U3&*,xeU@H
return page; P>0j]?RB
} <xOpm8
-$.$6"]
/** A!ba_14
* @param content ~i=/@;wRp
* The content to set. iePpJ>(
*/ );@@>~
public void setContent(List content){ pz:$n_XC}
this.content = content; fu?>O/Gn/
} :2
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/** GQ$0`?lp
* @param page ? Ls]k
* The page to set. _(0!bUs>
*/ fFqK.^Tn
publicvoid setPage(Page page){ tV[?WA[xt
this.page = page; !,V8?3.aJn
} U-Fr[1I6p
} "k"q)5c
Z@RAdwjR`p
t/u$Ts
H*A)U'`
]zhFFq`
2. 编写业务逻辑接口,并实现它(UserManager, L&Qdb xn
WvAl!^{`
UserManagerImpl) Y\%R6/Gj|u
java代码: %_@8f|# ,M
nR!qolh
U:J~Oy_Z
/*Created on 2005-7-15*/ >M[rOu
(d
package com.adt.service; )qzJu*cQ
qusgX;)
import net.sf.hibernate.HibernateException; ?$ Uk[
VrQw;-rQ
import org.flyware.util.page.Page; V.1sb
pI
sog?Mvoq
import com.adt.bo.Result; 4:nmo@K&~
*NFy%ktu
/** :uu\q7@'
* @author Joa -XPGl
*/ ?N,a {#w
publicinterface UserManager { .J&NM(qeZ
8ftLYMX@
public Result listUser(Page page)throws fx99@%Ii
K%2,z3ps
HibernateException;
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DS=kSkW^&5
} n"@3d.21
+M-' K19
",#rI+ el
QbV)+7II=
j<"0ym)A
java代码: qVZ=:D{
rv9qF |2r{
HTQ.kV
/*Created on 2005-7-15*/ zp% MK+x
package com.adt.service.impl; n!ea)+^
O|4~$7
import java.util.List; ^}U{O A
Dr7,>Yx
import net.sf.hibernate.HibernateException; Y 0$m~}j
unSF;S<
import org.flyware.util.page.Page; 0b?9LFd
import org.flyware.util.page.PageUtil; ;=_<\2
Y0&w;P
import com.adt.bo.Result; yoGE#+|7^
import com.adt.dao.UserDAO; |pq z(j7
import com.adt.exception.ObjectNotFoundException; s^L\hr
import com.adt.service.UserManager; jM2gu~
B?#@<2*=L
/** &fiDmUxj
* @author Joa XL EA|#
*/ B,e@v2jO|
publicclass UserManagerImpl implements UserManager { F]M3/M
P:ys--$"
private UserDAO userDAO; nUd(@@%m
XO"!)q F
/** 1V FAfv%}
* @param userDAO The userDAO to set. {;f`t3D
*/ + #S]uC
publicvoid setUserDAO(UserDAO userDAO){ pC_2_,6$
this.userDAO = userDAO; ~uzu*7U
} 9#O"^.Z !
r[EN`AxDb
/* (non-Javadoc) #/\FB'zC
* @see com.adt.service.UserManager#listUser h8pc<t\6
`\e@O#,^yI
(org.flyware.util.page.Page) p1J%=
*/ A3C<9wXx
public Result listUser(Page page)throws
UCvMW*gs
OwSr`2'9
HibernateException, ObjectNotFoundException { &&_W,id`
int totalRecords = userDAO.getUserCount(); vlEd=H,LT
if(totalRecords == 0) 5OpK~f5
throw new ObjectNotFoundException /x0zZ+}V
pOnZ7(
("userNotExist"); m"H9C-Y
page = PageUtil.createPage(page, totalRecords); rb`C:#j{J
List users = userDAO.getUserByPage(page); r4!zA-{
returnnew Result(page, users); !Aj_r^[X`
} `S$BBF;
R4@C>\c%m
} DX4
95<6*
pZjyzH{~
(8=Zr0He
D?X97jNm
L.+5`&
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Q'$aFl'NR
5-=mtvA:
询,接下来编写UserDAO的代码: "b-6kM
3. UserDAO 和 UserDAOImpl: HbZ3QW P
java代码: TO3Yz3+A
sNS!/
;v8,r#4
/*Created on 2005-7-15*/ T][\wyLx1
package com.adt.dao; :tzCuK?e
mQo]k
import java.util.List; 15Yy&9D
iwrdZLE
import org.flyware.util.page.Page; V,
)kw{](
#_|b;cf
import net.sf.hibernate.HibernateException; |iO2,99i
]<++w;#+x
/** VPtA
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* @author Joa $n(@hT>?
*/ 78 }iNGf
publicinterface UserDAO extends BaseDAO { MEq
()}7P
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publicList getUserByName(String name)throws U/0NN>V
j_p.KF'[?
HibernateException; Lrr6z05F Q
2 B5kpmH:
publicint getUserCount()throws HibernateException; "qQU ^FW
]7'Q2OU7
publicList getUserByPage(Page page)throws C.pNDpx-
'<4OA!,^)
HibernateException; I?l*GO+pz
Hdj0! bUx
} ]O&TU X@)
@: %}clZ
%# J8cB
.+{nfmc,c
_%Mu{Ni&
java代码: B>AIec\jG
q'q'v
S
|MTgKEsn
/*Created on 2005-7-15*/ `I_%`1 5>
package com.adt.dao.impl; fs~n{z,ja%
v_)cp9d]
import java.util.List; a,lH6lDk
~''qd\.f$
import org.flyware.util.page.Page; X3X~`~bAD
>nvreis
import net.sf.hibernate.HibernateException; SZvw>=)a
import net.sf.hibernate.Query; tlqDY1
AvP*p{we
import com.adt.dao.UserDAO; U{eC^yjt"o
(WN 'wp
/** [9aaHf@'
* @author Joa iT9cw`A^%
*/ -^\k+4;
public class UserDAOImpl extends BaseDAOHibernateImpl _lyP7$[:
c
}u:^ Mz
implements UserDAO { Mr/^V,rA
/i
DS#l\0
/* (non-Javadoc) >,hJ5-9
* @see com.adt.dao.UserDAO#getUserByName Fk=_Q
LI
^/Gjk
(java.lang.String) gjyg`%
*/ $@8\9Y
{
publicList getUserByName(String name)throws rv|k8
|mY<TWoX
HibernateException { SuGlNp>#qm
String querySentence = "FROM user in class EkWe6m
E3NYUHfZ
com.adt.po.User WHERE user.name=:name"; EsA^P2?_+
Query query = getSession().createQuery !!Mp;h'}-
J8? 6yd-7
(querySentence); gY*Cl1 Iz
query.setParameter("name", name); S)JZb_
return query.list(); .7E-
} W,AI E6F
!v`q%JW(
/* (non-Javadoc) NF&\<2kX
* @see com.adt.dao.UserDAO#getUserCount() R&PQ[ Xc
*/ K"-N:OV
publicint getUserCount()throws HibernateException { )m5<gp `
int count = 0; +".&A#wU
String querySentence = "SELECT count(*) FROM Nmi#$K[x
4Z]^v4vb
user in class com.adt.po.User"; s#*
mn
Query query = getSession().createQuery r\=p.cw<
:*c@6;2@
(querySentence); H,3$TNXy
count = ((Integer)query.iterate().next H@aCo(#
kQVl8KS
()).intValue(); ?7a<V+V:
return count; H~Q UN
} z^B!-FcIz>
7M*+!al9
/* (non-Javadoc) 3]}W
* @see com.adt.dao.UserDAO#getUserByPage O]{H2&k@
|S>nfL{TQe
(org.flyware.util.page.Page) 8h AI l
*/ 5l(;+#3y/
publicList getUserByPage(Page page)throws 8
LaZ5
X]y 3~|K
HibernateException { q &jW{
String querySentence = "FROM user in class a-%^!pN\M
k"Sw,"e>+
com.adt.po.User"; !lu$WJ{M
Query query = getSession().createQuery #o yvsS8
4S"K%2'O
(querySentence); cMK6
query.setFirstResult(page.getBeginIndex()) 3)dT+lZ
.setMaxResults(page.getEveryPage()); wu
3uu1J
return query.list(); {bc<0
} nMVThN*Ig
Th,2gX9
} e,1Jxz4QH
=
b)q.2'#
jv_sRV
1N#TL"lMS
!uHI5k,f
至此,一个完整的分页程序完成。前台的只需要调用 *r9I
1W
f#X`e'1
userManager.listUser(page)即可得到一个Page对象和结果集对象 x!"!oJG^k
wz6e^ g
的综合体,而传入的参数page对象则可以由前台传入,如果用 "Ny_RF
Bq:@ [pCQ
webwork,甚至可以直接在配置文件中指定。 lfI[r|
jq =-Y
下面给出一个webwork调用示例: cUy6/x9&
java代码: KCCS7l/
03rZz1
4Nq n47|>e
/*Created on 2005-6-17*/ d3n TJ X
package com.adt.action.user; RbrvY
.s2d
import java.util.List; t-E'foYfr`
q5OW1%
import org.apache.commons.logging.Log; +Z{4OJK
import org.apache.commons.logging.LogFactory; ~CM{?{z;
import org.flyware.util.page.Page; jpBE| Nm
EO|
kiC
import com.adt.bo.Result; .R-:vU880
import com.adt.service.UserService; cAktSoF
import com.opensymphony.xwork.Action; p.l]%\QI
".w*_1G7U
/** |]m&LC
* @author Joa nh E!Pk
*/ *dK A/.g
publicclass ListUser implementsAction{ Tzk8y7$[
-k<.Q=]<t
privatestaticfinal Log logger = LogFactory.getLog {yG)Ii
C ch1"j<k$
(ListUser.class); xH'H!
8
iK.MC%8?
private UserService userService; IGB>8$7
@Qx;J<{+g
private Page page; a7d782~
'Y&yt"cs
privateList users; ;^
/9sLW?#
I&(cdKY
z
/* 1C|j<w=i
* (non-Javadoc) hU4~`gp
* Stp??
* @see com.opensymphony.xwork.Action#execute() %{Ls$Y)
*/ #Xn#e
publicString execute()throwsException{ )FHaJ*&d
Result result = userService.listUser(page); h+Z|s
page = result.getPage(); \T[*|"RFZ
users = result.getContent(); tHu8|JrH+
return SUCCESS; lI5{]?'
} uZQ)A,#n;
a}Ov@7
/** F1,pAtA
* @return Returns the page. Y{J/Oib
*/ Gu%`__
public Page getPage(){ TY8 8PXW
return page; TVjY8L9'h
} eFeeloH?e*
De^is^{
/** h{h=',o1
* @return Returns the users. J%[K;WjrZJ
*/ t^7R6y
publicList getUsers(){ z.jGVF4
return users; ~q1s4^J
} d?S<h`{x
B@s\>QMm
/** Xajjzl\b
* @param page ++kiCoC
* The page to set. 4$|G$h
*/ cw^FOV*
publicvoid setPage(Page page){ ae^xuM?7
this.page = page; v:vA=R2
} "jpjBH:c$
-9Can4
/** k(7!W
* @param users bqe;) A7
* The users to set. MP3E]T~:
*/ j&&^PH9ZY
publicvoid setUsers(List users){ T2Vj&EA@
this.users = users; =*(d+[_
} .Ftml' !
`n %~#TJ
/** =-:o?&64
* @param userService jAJkCCG
* The userService to set. -I|yi'
*/ ]>AW
publicvoid setUserService(UserService userService){ )0%<ZVB
this.userService = userService; #A))#sT'R
} -\I0*L'$|\
} o?X\,}-s
?Rwn1.Z
z^oi15D|{
AX&1-U
PCU6E9~t2
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, \fKv+
g=%W"v
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 d6L(Q(:s
>?DrC /
么只需要: zMG4oRPP
java代码: :N[2*.c[
0P)c)x5
:,7VqCh3@
<?xml version="1.0"?> 95+}NJ;r
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork i'57| ;?
y.~5n[W
1.0//EN" "http://www.opensymphony.com/xwork/xwork- <W5F~K
;41
vw!i)JO8M
1.0.dtd"> ce;9UBkOg2
,fNiZ
<xwork> `Yut1N
G)putk@
<package name="user" extends="webwork- JhD8.@} b~
dxU[>m;
interceptors"> ybB}|4d&
2.x3^/
<!-- The default interceptor stack name ?&