Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 D"J',YN$
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 9.8%Iw
2]1u0-M5L
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 y~fKLIoz"
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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 O&1qL)
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分页支持类: =A.$~9P
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java代码: >~SS^I0
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package com.javaeye.common.util; T1]?E]m{
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import java.util.List; 7~ PL8
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publicclass PaginationSupport { Zge(UhZ
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publicfinalstaticint PAGESIZE = 30; ?@
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privateint pageSize = PAGESIZE; _dJ(h6%3
!R=@Nr>
privateList items; v1TFzcHl<
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privateint totalCount; Mf1(4F
){*+s RBW
privateint[] indexes = newint[0]; yO q@w!xz
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privateint startIndex = 0; %GHGd'KO&
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public PaginationSupport(List items, int {_QdB;VwH
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totalCount){ `#N/]4(j
setPageSize(PAGESIZE); =V[uXm
setTotalCount(totalCount); Rff F:,b
setItems(items); `Mnu<)v
setStartIndex(0); 4J2^zx,H
}
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public PaginationSupport(List items, int s6!6Oqh
F$C6( C?
totalCount, int startIndex){ Zh=arlk
setPageSize(PAGESIZE); bGPE0}b
setTotalCount(totalCount); ~HZdIPcC
setItems(items); Smr{+m a
setStartIndex(startIndex); fpD$%.y'J
} rtV`Q[E
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public PaginationSupport(List items, int m`/Nl<
EB~]6.1
totalCount, int pageSize, int startIndex){ Lo%n{*if
setPageSize(pageSize); '5e,@t%y
setTotalCount(totalCount); Zxa.x?:?n
setItems(items); LeKovt%
setStartIndex(startIndex); }LzBo\
} x:|Y)Dn\
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publicList getItems(){ jD:
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return items; +yGQt3U
} '![oLy
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publicvoid setItems(List items){ a`xq
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this.items = items; p4`1^}f&Ie
} H_+n_r*
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publicint getPageSize(){ bSB%hFp=Cp
return pageSize; 2w 2Bc+#o
} 2u"lc'9v
#Y'eS'lv4
publicvoid setPageSize(int pageSize){ <W4F`6`x
this.pageSize = pageSize; 3/G^V'Yu
} %TB(E<p`
Sc)^k
publicint getTotalCount(){ $l7^-SK`E
return totalCount;
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} o[|[xuTm
hXW` n*Zw
publicvoid setTotalCount(int totalCount){ ).T&fa"
if(totalCount > 0){ %opBJ
this.totalCount = totalCount; g3R(,IH
int count = totalCount / S;|:ci<[=
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pageSize; <`H0i*|Ued
if(totalCount % pageSize > 0) e+
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count++; Knq9"k
indexes = newint[count]; 1!#85SMx
for(int i = 0; i < count; i++){ 55[ 4)*
indexes = pageSize * hHs/Qtq
5> k:PKHL
i; !Ok(mgV$/
} aSL`yuXu
}else{ \2SbW7"/;P
this.totalCount = 0; rzjVUPdnh
} )>volP
} v4$/LUJZp
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publicint[] getIndexes(){ 3h@]cWp
return indexes; D6 B-#u!M
} .sMs_ 5D
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publicvoid setIndexes(int[] indexes){ sI ,!+
this.indexes = indexes; C2
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} <izQ]\kL
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publicint getStartIndex(){ \kADh?phV
return startIndex; N& _~y|
} KA3U W
=c8}^3L~7
publicvoid setStartIndex(int startIndex){ b#j:)PA0C
if(totalCount <= 0) rhv~H"qzW
this.startIndex = 0; j=\h|^gA
elseif(startIndex >= totalCount) 9zaNfs
this.startIndex = indexes /l$x}
1S{Biqi+
[indexes.length - 1]; /dnwN7Gf
elseif(startIndex < 0) )"?4d[ 5
this.startIndex = 0; z8kO)'
else{ $vn6%M[
this.startIndex = indexes !_I1=yi
2TK \pfD
[startIndex / pageSize]; hlVye&;b8
} 0<M-asI?
} qwTz7r
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publicint getNextIndex(){ Vk5Z[w a
int nextIndex = getStartIndex() + sXLW';Fz
hpdI5
pageSize; =SDex.ZK]
if(nextIndex >= totalCount) R2bq hSlF
return getStartIndex(); u?').c4
else 4pmeu:26
return nextIndex; z]7 WC
} u@a){A(P
bG;fwgAr
publicint getPreviousIndex(){ 1{uxpYAP=
int previousIndex = getStartIndex() - UpoSC
Y,]Lk<Hm3
pageSize; B-I4(w($
if(previousIndex < 0) I}$`gUXX8x
return0; S
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else nz 10/nw
return previousIndex; i4D(8;
} d_[H|H9i6
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} uWS]l[Ga
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抽象业务类 !$)reaS
java代码: HcRw9,I'
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/** 3Tr,waV
* Created on 2005-7-12 hY}Q|-|
*/ @f[-
package com.javaeye.common.business; =<\22d5L
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import java.io.Serializable; 2H%9l@}u
import java.util.List; vNi;)"&*
xd?=#d
import org.hibernate.Criteria; ,fjY|ip
import org.hibernate.HibernateException; O:BdZ5
b
import org.hibernate.Session; A}fm).Wp@
import org.hibernate.criterion.DetachedCriteria; Y7GsL7I
import org.hibernate.criterion.Projections; #p+iwW-
import L:
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wd:Yy
org.springframework.orm.hibernate3.HibernateCallback; !ooi.Oz*Tu
import ~EtGR #
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org.springframework.orm.hibernate3.support.HibernateDaoS Om.%K>V
V|Bwle
upport; .0dGS
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import com.javaeye.common.util.PaginationSupport; |bk9<i ?
j"Jf|Hq $
public abstract class AbstractManager extends o
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HibernateDaoSupport { Na@bXcz)
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privateboolean cacheQueries = false; 9]Jv
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privateString queryCacheRegion; 2n.HmS
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publicvoid setCacheQueries(boolean /? %V%
n
@ ]u@e4T
cacheQueries){ Cm;cmPPl
this.cacheQueries = cacheQueries; U\%r33L )
} $SQ$2\iC
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publicvoid setQueryCacheRegion(String 3$hIc)
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queryCacheRegion){ 2]kGDeSr
this.queryCacheRegion = ?|,:;^2l1
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queryCacheRegion; F'M X9P
} ]QlW{J
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publicvoid save(finalObject entity){ [~Ky{:@)[
getHibernateTemplate().save(entity); 1v&!%9
} `M~R4lr
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publicvoid persist(finalObject entity){ he(K
getHibernateTemplate().save(entity); uD/@d'd_4L
} }$i"t8"s
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publicvoid update(finalObject entity){ 8XJi }YPQ
getHibernateTemplate().update(entity); Q u2
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} \k5"&]I3
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publicvoid delete(finalObject entity){ OxDqLX
getHibernateTemplate().delete(entity); j7)mC4o:%
} LEM%B??&5z
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publicObject load(finalClass entity,
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finalSerializable id){ 2.WI".&y=
return getHibernateTemplate().load (s&:D`e
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(entity, id); H.ZF~Yuw
} .1TuHC\mC
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publicObject get(finalClass entity, -$"$r ~ad
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finalSerializable id){ {@CQ
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return getHibernateTemplate().get Btxtu"]nJo
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(entity, id); !-tw
} yZ{yzv'D&
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publicList findAll(finalClass entity){ KANR=G
return getHibernateTemplate().find("from ;@=3
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" + entity.getName()); oc)`hg2=
} y>}r
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publicList findByNamedQuery(finalString \t)va:y
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namedQuery){ ~588M
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return getHibernateTemplate 4/~x+tdc
lv=q( &
().findByNamedQuery(namedQuery); { Z
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} %W9R08`
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publicList findByNamedQuery(finalString query, gdeM,A|
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finalObject parameter){ d)1gpRp
return getHibernateTemplate Vm<_e
o3`U;@ &u
().findByNamedQuery(query, parameter); C<C$df
} 0F-{YQr>
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publicList findByNamedQuery(finalString query, F$\Da)Y
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finalObject[] parameters){ Qu[QcB{ro-
return getHibernateTemplate j~>{P=_}
`2]0 X#R
().findByNamedQuery(query, parameters); ;ZUj2WxE
} N<i5X.X
2|^@=.4\
publicList find(finalString query){ \1G'{#Q
return getHibernateTemplate().find 0Qa0
H2BRId
(query); F8Ety^9>9
} OiQf=Uz\
WGn=3(4
publicList find(finalString query, finalObject _cQ
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parameter){ '27$x&6>S
return getHibernateTemplate().find pi"M*$
^%,{R},s
(query, parameter); ]Z5m_-I
} Q//
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public PaginationSupport findPageByCriteria #epbc K
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(final DetachedCriteria detachedCriteria){ =KHb0d |.
return findPageByCriteria X3G593ts
0\XWdTj{
(detachedCriteria, PaginationSupport.PAGESIZE, 0); **%&|9He
} ]6B9\C.2-_
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public PaginationSupport findPageByCriteria 5NZuaN
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(final DetachedCriteria detachedCriteria, finalint Lbrl CB+
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startIndex){ ]]K?Q
)9x
return findPageByCriteria Zq8 5q
a6n@
(detachedCriteria, PaginationSupport.PAGESIZE, 9Of;8R
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startIndex); V\zcv @
} `f}s<At
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public PaginationSupport findPageByCriteria MS;^:t1`
}{N#JTmjB#
(final DetachedCriteria detachedCriteria, finalint @>O7/d?O
;)FvTm'"\.
pageSize, _MC',p&
finalint startIndex){ DQY1oM)D!
return(PaginationSupport) gGvL6Fu
=F_uK7W
getHibernateTemplate().execute(new HibernateCallback(){ {mD0ug
publicObject doInHibernate hx0 t!k(3
XA#qBxp/h
(Session session)throws HibernateException { RL4|!HzR
Criteria criteria = u;$qJjS
N
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detachedCriteria.getExecutableCriteria(session); dY}5Kmt
int totalCount = y`zdI_!7
e">&B]#}
((Integer) criteria.setProjection(Projections.rowCount dYISjk@
_'cB<9P
()).uniqueResult()).intValue(); 1R@G7m
criteria.setProjection <fHHrmZ#/.
S*G^U1Sc+
(null); i}8OaX3x
List items = E'{:HX
.>;??BG}
criteria.setFirstResult(startIndex).setMaxResults <7`k[~)VB
]Y]]X[@
(pageSize).list(); HR?T
PaginationSupport ps = !q$VnqFk
|e#W;q$v
new PaginationSupport(items, totalCount, pageSize, %G(VYCeK
r
jn:E
startIndex); EFDmNud`Q
return ps; ?a,#p
} 1@I#Fv
}, true); |s/Kb]t
} ugN%8N
5GAW3j{
public List findAllByCriteria(final " TCJT390
kO`!!M[Oo
DetachedCriteria detachedCriteria){ ?;Sg,.J
return(List) getHibernateTemplate 4j0;okQWV'
a=ZVKb
().execute(new HibernateCallback(){ a\m=E#G
publicObject doInHibernate S^~"#
uDG>m7(}/h
(Session session)throws HibernateException { rhOxyY0
Criteria criteria = KJ/Gv#Kj
}#.OJub
detachedCriteria.getExecutableCriteria(session); eptw)S-j
return criteria.list(); U&(gNuR>J
} k {{eyC
}, true);
]Z UE !
} JO]?u(m01
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public int getCountByCriteria(final 8[@Y`j8
XjzGtZ#6
DetachedCriteria detachedCriteria){ IX
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Integer count = (Integer) `yl|NL
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getHibernateTemplate().execute(new HibernateCallback(){ ;K l'[~z
publicObject doInHibernate a%m>v,
g@O?0,+1
(Session session)throws HibernateException { g}6M+QNj
Criteria criteria = 9:%')M&Q
(JOR:
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detachedCriteria.getExecutableCriteria(session); 8rJf2zL
return !j #8zN
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criteria.setProjection(Projections.rowCount Tl"r#
&)q>Z!C-l
()).uniqueResult(); V?T&>s
} ?Nt m5(R
}, true); TRgj`FG
return count.intValue(); LD WYFOGQ
} V@z/%=PJ
} It'kO jx]
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" 5Pqvi
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,{ 0&NX
用户在web层构造查询条件detachedCriteria,和可选的 NP\/9
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 R SWw4}
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PaginationSupport的实例ps。 n|.>41bJ
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ps.getItems()得到已分页好的结果集 %,8
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ps.getIndexes()得到分页索引的数组 m=iKu(2xRq
ps.getTotalCount()得到总结果数 FgP{
ps.getStartIndex()当前分页索引 w2!5TKZ`
ps.getNextIndex()下一页索引 nH?#_ 5F1
ps.getPreviousIndex()上一页索引 l,QO+
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 5Yk|
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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 ?|<p^:
@, z4{B
一下代码重构了。 ,I f9w$(z
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我把原本我的做法也提供出来供大家讨论吧: 2-duzc
#@M'*X_%}K
首先,为了实现分页查询,我封装了一个Page类: riglEA[^
java代码: t/x]vCP,2D
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/*Created on 2005-4-14*/ S }G3h a
package org.flyware.util.page; \xk8+= /A
F
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/** {`% q0Nr
* @author Joa d^aLue>g;+
* g.Kyfs4`
*/ !?{%9
publicclass Page { "SwM%j
N2EX`@_2
/** imply if the page has previous page */ N!af1zj
privateboolean hasPrePage; "4QD\k5
&K,rNH'R
/** imply if the page has next page */ aD?ySc}
privateboolean hasNextPage; 7/c9azmC
} q r
,
/** the number of every page */ p@=B\A]
privateint everyPage; ;u?H#\J,
1GgG9I
/** the total page number */ upF^k%<y:
privateint totalPage; &G!2T!xx
n0@ \x=9
/** the number of current page */ wArtg'=X
privateint currentPage; P/~kX_
]0@
J)Z09
/** the begin index of the records by the current rt!Uix&
sJ cwN.s
query */ @I0[B<,:G
privateint beginIndex; ~_yz\;#
8` f=Eh
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/** The default constructor */ {
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public Page(){ vZ2/>}!Z=
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p%Q
} 75#&hi/~
Ft$tL;
/** construct the page by everyPage w^aI1M50
* @param everyPage ]^@!ID$c
* */ :k.C|V!W
public Page(int everyPage){ |R$/oq
this.everyPage = everyPage; zJa,kN|m
} 1Igo9rv
niP/i
/** The whole constructor */ aY@st]p
public Page(boolean hasPrePage, boolean hasNextPage, ZU-vZD>
k'$UA$2d
#i~2C@]
int everyPage, int totalPage, )'gO?cN
int currentPage, int beginIndex){ ,~,{$\p
this.hasPrePage = hasPrePage; ~$3X>?Q
this.hasNextPage = hasNextPage; _;].
this.everyPage = everyPage; }
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this.totalPage = totalPage; Yhkn(k2
this.currentPage = currentPage; {Deg1V!x>
this.beginIndex = beginIndex; $f^ \fa[
} w-.=u3
/_MEb42&
/** l^ aUN
* @return O*7Gl G
* Returns the beginIndex. /*8Ms`
*/ Z#lZn!EbK
publicint getBeginIndex(){ D.\s mk
return beginIndex; qc-4;m o
} 1"Z61gXrz
M4 :}`p=
/** |
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* @param beginIndex g^EkRBU
* The beginIndex to set. ZiS<vWa3R
*/ \D37l_
publicvoid setBeginIndex(int beginIndex){ 6mi:%)"
this.beginIndex = beginIndex; hh!^^emo
} ,!RbFME&H
. !|3a
/** +EWfsKz
* @return M)oy3y^&
* Returns the currentPage. S>oQm
*/ 6(`Bl$M9
publicint getCurrentPage(){ z5G$'
return currentPage; 5`B!1
} mqg[2VTRP
|hprk-R*OH
/** 9aE!!
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* @param currentPage Zw[A1!T,
* The currentPage to set. 9Xg+$/
*/ ;@$B{/Q
publicvoid setCurrentPage(int currentPage){ :Sx!jx>W
this.currentPage = currentPage; *k(>Qsb "
} od7 [h5r
X=<-rFW
/** 3UIR^Rh+
* @return 4q`$nI Bi
* Returns the everyPage.
=jX'FNv#
*/ y/ #{pyJ
publicint getEveryPage(){ + a%Vp!y
return everyPage; R~$W
} }?pY~f
rH9wRY(
/** \B'rWk33,
* @param everyPage pm-SDp>s
* The everyPage to set. do2~LmeW
*/ n_Ht{2I
publicvoid setEveryPage(int everyPage){ TS9=A1J#
this.everyPage = everyPage; h]rF2 B
} &J)q _Z8
btC0w^5
/** |=7ouFl
* @return 'Jb6CRn
* Returns the hasNextPage. u;xl}
*/ DlkHE8r\
publicboolean getHasNextPage(){ %E95R8SL
return hasNextPage; g.v)qB
} ?NZKu6
paUlp7x
/** 18|i{fE;
* @param hasNextPage 8#OcrJzC
* The hasNextPage to set. fX,L;Se"
*/ %-y%Q.;k?
publicvoid setHasNextPage(boolean hasNextPage){ sE4=2p`x
this.hasNextPage = hasNextPage; c5K@<=?,E
} }s_'q~R
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/** =qY!<DB[L
* @return PQ`p:=~>:i
* Returns the hasPrePage. lMu}|d
*/ -9XB.)\#
publicboolean getHasPrePage(){ ({#9gTP2b
return hasPrePage; `mro2A
} &TqY\l
^`Tns6u>
/** 3:Aw.-,i\
* @param hasPrePage =&QC&CqEi
* The hasPrePage to set. |s&jWM$
*/ Ca[H<nyj
publicvoid setHasPrePage(boolean hasPrePage){ tZS-e6*S
this.hasPrePage = hasPrePage; En:.U9?X
} SF.4["$
-@49Zh2'
/** L-}>;M$Y)
* @return Returns the totalPage. adG=L9
"n
* Y6T1_XG
*/ W+3ZuAP\n
publicint getTotalPage(){ MHN?ZHC)
return totalPage; 3[kY:5-
} - aCtk$3
Cx $M
/** ,f`435R
* @param totalPage DPuz'e*
* The totalPage to set. 6iwIEb
*/ R u^v!l`!7
publicvoid setTotalPage(int totalPage){ O$}p}%%y7
this.totalPage = totalPage; -!uut7Z|
} aRBTuLa)fo
6"^Yn.
} {C>.fg%t
% AqUVt9}
+u%^YBr
%G6ml,
Z:3N*YkL
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 q\Cg2[nn2
vn"2"hPF|
个PageUtil,负责对Page对象进行构造: z?$F2+f&
java代码: YfBb=rN2s
P-9[,3Zd
kTG4h@w
/*Created on 2005-4-14*/ w9I7pIIl
package org.flyware.util.page; a!MhxM5
1:<= zqh0
import org.apache.commons.logging.Log; O5HK2Xg,C
import org.apache.commons.logging.LogFactory; %Gp%l
jEj#|w
/** ~F8M_
* @author Joa Jy)E!{#x
* {6%vmMbJ
*/ y9d[-j
;w
publicclass PageUtil { mA|&K8H
y:Xs/RS
privatestaticfinal Log logger = LogFactory.getLog L/1zG/@
ZD{%0uh
(PageUtil.class); sS 5 ]d8
!'>(r K$
/** &V7@ TZ
* Use the origin page to create a new page h&eu}aF
* @param page dkTj
KV
* @param totalRecords pKDP1S#<
* @return `n%uvo}UT
*/ K;jV"R<9
publicstatic Page createPage(Page page, int OjxaA[$
85;
BS'
totalRecords){ E"!I[
return createPage(page.getEveryPage(),
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;AV[bjRE\
page.getCurrentPage(), totalRecords); Va^Y3/
} f8`K8Y]4
z@\C/wX
/** Ed[ tmaEuV
* the basic page utils not including exception 6^U8Utx
<p"[jC2zF;
handler /]H6'
* @param everyPage hwF9LD~^
* @param currentPage UhuEE
* @param totalRecords b%`^KEvwfo
* @return page VW^6qf/,
*/ ConXP\M-
publicstatic Page createPage(int everyPage, int y,{=*2Yt
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currentPage, int totalRecords){ +2%ih!
everyPage = getEveryPage(everyPage); lSv?!2
currentPage = getCurrentPage(currentPage); >]N}3J}47g
int beginIndex = getBeginIndex(everyPage, *Ag</g@ h
j)4:*R.Z]
currentPage); ,ra!O=d~0
int totalPage = getTotalPage(everyPage, 4yhan/zA
O~t]:p9_
totalRecords); Jt79M(Hp!
boolean hasNextPage = hasNextPage(currentPage, 6"@+Jz
JCoDe.
totalPage); -2NXQ+m ;
boolean hasPrePage = hasPrePage(currentPage); oRl~x^[%[-
>TSPEvWc
returnnew Page(hasPrePage, hasNextPage, 8bQ\7jb
everyPage, totalPage, S/YT
V
currentPage, #CKPNk
c
USgZ%xk2
beginIndex); 9Q{-4yF9k
} l1 (6*+
sywSvnPuYZ
privatestaticint getEveryPage(int everyPage){ 3m
RP.<=
return everyPage == 0 ? 10 : everyPage; Ore>j+
} ?f@g1jJP
>*jcXao^
privatestaticint getCurrentPage(int currentPage){ Dq=&K,5;
return currentPage == 0 ? 1 : currentPage; 0p6
} WXJEAje
Z(Styn/x
privatestaticint getBeginIndex(int everyPage, int q18IqY*Lo
K%NNw7\A
currentPage){ Ze `=n
return(currentPage - 1) * everyPage; +tsF.Is!t
} a7?z{ssEi
<2b&AF{En
privatestaticint getTotalPage(int everyPage, int % zP]z
WiDl[l"{9
totalRecords){ ?`9XFE~a!
int totalPage = 0; #G</RYM~m
xBba&A]=
if(totalRecords % everyPage == 0) Po(Y',xI[
totalPage = totalRecords / everyPage; CC{*'p6
else yT[CC>]l
totalPage = totalRecords / everyPage + 1 ; 2~`lvx
b&q!uFP
return totalPage; @bPR"j5D
} &j}08aK%
#vwK6'z
privatestaticboolean hasPrePage(int currentPage){ Uh6LU5
return currentPage == 1 ? false : true; d|I_SI1
} .bdp=vbA
\"]KF8c^_
privatestaticboolean hasNextPage(int currentPage, b/#SkxW#S
7rIz
int totalPage){ 4OX2GH=W
return currentPage == totalPage || totalPage == hc"l^a!7ic
IP?15l w
0 ? false : true; \[\4= !v
} *}F>c3x]
EY$Dtb+g8
DIqM\ ><
} }I}/e
v
Ux[2 +Cf
,=_)tX^
pyHU+B
Dx)>`yJk$;
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。 %fbV\@jDCX
CdEQiu
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 ]et
]Vkg
/Dd.C<F
做法如下: ?g{--'L
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 t4;eabZK
%*}h{n
的信息,和一个结果集List: 0sMNp
java代码: ]!c59%f=
h 8%(,$*
v9,<2
/*Created on 2005-6-13*/ us5<18M5
package com.adt.bo; 1;*4yJ2
M2kvj'WWq
import java.util.List; bIXudE[8zq
I`~Giz7@
import org.flyware.util.page.Page; Y9/`w@"v
d/8p?Km
/** k~0#Iy_{M
* @author Joa vw'xmzgA
*/ JpRn)e'Z
publicclass Result { 4Wd
H!z
]/9@^D}&
private Page page; x/pX?k
B_uhNLd
private List content; 0&~JC>S
6%a9%Is!O
/** -Qy@-s $
* The default constructor ]x1;uE?1J
*/ &lCOhP#
public Result(){ a1>Tz
super(); sSLVR^
} [+F6C
dEhFuNO<2
/** 0$qK: ze
* The constructor using fields 2M+}o"g
* 6`h}#@ (
* @param page aMJW__,
* @param content XtZeT~/7RT
*/ Yu}[RXC(=
public Result(Page page, List content){ hS 9^Bi
this.page = page; %ws@t"aER
this.content = content; 43}uW,P
} aBd>.]l?
3Q#Tut
/** j0b>n#e7
* @return Returns the content. dEI]|i
r
*/ dHkI9;
publicList getContent(){ =o)B1(v@.
return content; o?g9Grk
} Hmx
Y{KB
&R))c|>OT&
/** ~c=F$M^"c
* @return Returns the page. 7<*,O&![|
*/ FfC\uuRe
public Page getPage(){ V2SHF
return page; nh]HEG0CZJ
} +w2 `
hRNnj
/** Gn %"B6
* @param content NdmwQJ7e"
* The content to set. 1d!TU=*
*/ T<%%f.x[s
public void setContent(List content){ _7;D0l
this.content = content; 3>6rO4,
} r+usMF<'
oh7tE$"c
/** Yw6uh4
* @param page 1'%n?\OK66
* The page to set. vO)]~AiB
*/ z~th{4#E;
publicvoid setPage(Page page){ y
q!{\@-
this.page = page; v"l8[::
} o;u~Yg
} **.g^Pyc
AHU=`z
PDS?>Jg(
cEIs9;
c5Hyja=
2. 编写业务逻辑接口,并实现它(UserManager, TSH'OW !b
X.V4YmZ-;
UserManagerImpl) */OKg;IMi
java代码: bZ#5\L2
6MpV,2:>
q8}he~a
/*Created on 2005-7-15*/ ><qA+/4]_
package com.adt.service; )XDbg>
|zJ2ZE|
import net.sf.hibernate.HibernateException; B dP+>Ij
')TS'p,n
import org.flyware.util.page.Page; (K('@W%\?
/z)Nz2W
import com.adt.bo.Result; {TvB3QOsj
ovZ!}
/** )|GYxG;8C
* @author Joa ~|S}$|Mi50
*/ m:c0S8#:
publicinterface UserManager { qJJ},4}
vwzElZ{C:v
public Result listUser(Page page)throws 9TbbIP1
pM~-o?
HibernateException; S4pEBbV^n
('2Z&5
} m%b#B>J,n
iqFC~].)
!R![:T\,
)SJ"IY\P
VI-6t"l
java代码: z3{Cp:Mn
HP\5gLVXY
lx7]rkWo|a
/*Created on 2005-7-15*/ e|q~t
{=9S
package com.adt.service.impl; ornU8H`
(mioKO )?v
import java.util.List; /iL*)
6Fc*&7Z+
import net.sf.hibernate.HibernateException; wG73GD38
agq4Zy
import org.flyware.util.page.Page; {B4.G8%Z
import org.flyware.util.page.PageUtil; ^v+p@k
UjMWSPEBy
import com.adt.bo.Result; 0lOR.}]q
import com.adt.dao.UserDAO; }D-jTZlC
import com.adt.exception.ObjectNotFoundException; D^}2ilk!
import com.adt.service.UserManager; Ir=G\/A
e-%q!F(Bf
/** cgO<%_l3`
* @author Joa @1 i<=r
*/ l&5Tft
publicclass UserManagerImpl implements UserManager { +|TXKhm{
ErgWs Aw-
private UserDAO userDAO; Er
-rm
50`|#zF^#
/** ";/ogFi
* @param userDAO The userDAO to set. y.-Kqa~
*/ 2qQ;U?:q
publicvoid setUserDAO(UserDAO userDAO){
LnM$@
this.userDAO = userDAO; 'rq@9$h1W
} xdVsbW)L2
i5|)|x3
/* (non-Javadoc) /,~g"y.;,
* @see com.adt.service.UserManager#listUser wk{]eD%
C=IN "
(org.flyware.util.page.Page) 7 fXJP5j
*/ :F9Oj1lM%
public Result listUser(Page page)throws %
[~0<uO
3`)ej`
HibernateException, ObjectNotFoundException { ,9MNB3
int totalRecords = userDAO.getUserCount(); 8n:N#4Dh^
if(totalRecords == 0) g1:%986jv
throw new ObjectNotFoundException Z>l<.T"t'
73nM9
("userNotExist"); $sUn'62JlU
page = PageUtil.createPage(page, totalRecords); 18p4]:L
List users = userDAO.getUserByPage(page); &C)97E
returnnew Result(page, users); -8R SE4)
} Pa?{}A
D6"d\Fm<
} L}'^FqO[IW
Z~}9^ (qc
6{0MprY
eKo=g|D
f0R+Mz8{
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 z@ `u$D$n
((<\VQ,>(
询,接下来编写UserDAO的代码: P,(_y8
3. UserDAO 和 UserDAOImpl: g++-v HD
java代码: EEo I|
_%23L|
Mz86bb^J
/*Created on 2005-7-15*/ M%RH4%NZ0
package com.adt.dao; &pR 8sySu
TAqX
f_
import java.util.List; l ?YO!$
>YsM'.EF D
import org.flyware.util.page.Page; 7\ZSXQy1W
g_A#WQyh\'
import net.sf.hibernate.HibernateException; 7%[ YX
MOay^{u
/** JIHIKH-#
* @author Joa )]4=anJu@|
*/ [LUqF?K&
publicinterface UserDAO extends BaseDAO { YW&`PJ9o
4%|r$E/TQ
publicList getUserByName(String name)throws 6eA)d#
t* p%!xsH
HibernateException; SXN]${
mdo$d-d&
publicint getUserCount()throws HibernateException; -M_>]ubG
7$t['2j3
publicList getUserByPage(Page page)throws wA)nryXV
OVc)PMp
HibernateException; 2-Wy@\
>oaL -01i
} o^MoU2c
ZU;jz[}
F6b;qb6n
}qWB=,8HQ
Qw
}1mRv
java代码: Z",2db
DsD? &:
0IP0zil
/*Created on 2005-7-15*/ s&<76kwl
package com.adt.dao.impl; 5tzO=gO[
jA[")RVG
import java.util.List; 5hDy62PRr
Cud!JpL
import org.flyware.util.page.Page; lC,~_Yb
g+c%J#F=
import net.sf.hibernate.HibernateException; ,'9R/7%s
import net.sf.hibernate.Query; {^^LeUd#V
hE$3l+
import com.adt.dao.UserDAO; m|t\w|B2
C5$?Y8B3
/** G007[|
* @author Joa (0.JoeA`y
*/ +c,
^KHW
public class UserDAOImpl extends BaseDAOHibernateImpl =6i+K.}e
C*B5"s"
implements UserDAO { m/(/!MVy
6A}tA$*s7
/* (non-Javadoc) O=lRI)6w@e
* @see com.adt.dao.UserDAO#getUserByName 6pfkv2.}
z"QXPIXPk
(java.lang.String) i~R+g3oi
*/ 3Co1bY:
publicList getUserByName(String name)throws D ]
n|d+
Fp[49
HibernateException { ]gm3|-EiY
String querySentence = "FROM user in class QD%6K=8Q
>!{8)ti
com.adt.po.User WHERE user.name=:name"; _x#y
Query query = getSession().createQuery C dPQhv)m
UQ7La 7"
(querySentence); E|SmvIV-
query.setParameter("name", name); ]KXyi;n2
return query.list(); 8>D*U0sNl
} NWQ7%~#k*
,Mi'NO
/* (non-Javadoc) Qu7ML]e?z
* @see com.adt.dao.UserDAO#getUserCount() F MYcZ+4
*/ kM=&Tfpj
publicint getUserCount()throws HibernateException { -vk/z+-^!
int count = 0; b9 li
String querySentence = "SELECT count(*) FROM Gl45HyY_
QtWe,+WWV
user in class com.adt.po.User"; ,1lW`Krx
Query query = getSession().createQuery MPyDG"B *
A&%7Z^Pp
(querySentence); "&^KnWk=
count = ((Integer)query.iterate().next IB 4L(n1
H1KXAy`&
()).intValue(); 3DB= Xh
return count; 2Dvq3VbiO"
} O&~
@ior
nmE H/a
/* (non-Javadoc) QQS"K
g
* @see com.adt.dao.UserDAO#getUserByPage yv>uzb`N
i.?rom
(org.flyware.util.page.Page) _4#7 ? p
*/ 9Av{>W?
publicList getUserByPage(Page page)throws b E40^e
In!^+j
HibernateException { b].U/=Hs
String querySentence = "FROM user in class xXmlHo<D
NiE`u m
com.adt.po.User"; _D8 zKp
Query query = getSession().createQuery ;pfN
FYefn3b
(querySentence); .'2I9P\!
query.setFirstResult(page.getBeginIndex()) x;~@T9.
.setMaxResults(page.getEveryPage()); AE`{k-3=%
return query.list(); Qm"~XP
} .W2w/RayC
[C~N#S[]
} VsK8 :[Al
m]
p]J_6A
REi"Aj=
d.B<1"MQ
*H=h7ESq
至此,一个完整的分页程序完成。前台的只需要调用 +2Aggv>*
mRGr+m
userManager.listUser(page)即可得到一个Page对象和结果集对象 -qpM 6t
^(7l!
的综合体,而传入的参数page对象则可以由前台传入,如果用 X(DP=C}v9
<4 /q5*&
webwork,甚至可以直接在配置文件中指定。 F*Yx1vj
dpt P(H
下面给出一个webwork调用示例: oq1wU@n
java代码: &f?JtpB
gQY`qz
s`.J!^u`
/*Created on 2005-6-17*/ N#R8ez`
package com.adt.action.user; =_Z.x&fi
16.?45
import java.util.List; 9fM=5
,5 3`t
import org.apache.commons.logging.Log; AAB_Ytf
import org.apache.commons.logging.LogFactory; ;4v`FC>
import org.flyware.util.page.Page; HoWK#Nz\
"EWq{l_I5$
import com.adt.bo.Result; #Wb4*
import com.adt.service.UserService; EF=5[$
u
import com.opensymphony.xwork.Action; \]\GDpu[
Bw[IW[(~!
/** XZ(<Mo\v
* @author Joa Gs04)KJm<
*/ X .K*</(g
publicclass ListUser implementsAction{ *Id[6Z
?\X9Ei
privatestaticfinal Log logger = LogFactory.getLog ;vpq0t`
5pHv5e
(ListUser.class); 65RD68a
*F(<:3;2
private UserService userService; *$1F|G
^b= ;
private Page page; lx?v
.:zl\
c+whpQ=01
privateList users; wp:Zur5Y
65mfq&"P?
/* ,k9.1kjO*)
* (non-Javadoc) i?mUQ'H
* 7 VYhRC-
* @see com.opensymphony.xwork.Action#execute() UvqnNA
*/ Zl]@;*u
publicString execute()throwsException{ E2S#REB4
Result result = userService.listUser(page); V%zo[A
page = result.getPage(); >+:cTQ|q
users = result.getContent();
xKepZ
return SUCCESS; {q~N$"#
} F
hyY+{%
5,Co(K
/** 5.kKg=a
* @return Returns the page. k6\&[BQs
*/ 'S=eW_ 0/
public Page getPage(){ )M7~RN
return page; TA#pA(k
} h 3 J&
Q,ZV C
/** lhBAT%U\
* @return Returns the users. Jt?`(H
*/ |Fq\%y#
publicList getUsers(){ k#p6QAhS
return users; 'RV wxd
} sLK$H|%>m
*WWDwY@!u
/** JX{rum
* @param page 0 r;tI"
* The page to set. C9>^!?>
*/ `bd9N!K
publicvoid setPage(Page page){ VZ9`Kbu
this.page = page; D8$4P T0u
} B!)Tytm9u
@%^h|g8>Fu
/** #210 Yp#
* @param users yv$hIU2X
* The users to set. koj*3@\p/
*/ g12.4+
publicvoid setUsers(List users){ T[J8zLO
this.users = users; "VMb1Zhf
} b.)jJLWv@
<DEu]-'>
/** ?U2 'L2y
* @param userService w3ZOCWJS
* The userService to set. iU#"G" &
*/ 1h{7dLA
publicvoid setUserService(UserService userService){ h+9~^<oFl
this.userService = userService; wiM4,
} YH{n
} 0}g~69Z1=
D\DwBZ>
5hDPX\
* C*aH6*
d"lk"R
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, q$}gQ9'z'
71\GK
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 g$qM}#s0}
uaha)W;'9
么只需要: nM99AW
java代码: ]qEg5:yY
Bc<