Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 4Fa~Aog
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 3("_Z%
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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 \"qY "V
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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 bG 7O
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分页支持类: E08klC0
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java代码: Bs13^^hu
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package com.javaeye.common.util; 5k!g%sZ
* ;-*x6
import java.util.List; +?F[/?s5qz
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publicclass PaginationSupport { ={_C&57N1
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publicfinalstaticint PAGESIZE = 30; +vvv[
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privateint pageSize = PAGESIZE; V\t.3vT
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privateList items; @"hb) 8ng
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privateint totalCount; 5*E]ETo@R
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privateint[] indexes = newint[0]; )n+Lo&C<
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privateint startIndex = 0; fo5iJz"Z
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public PaginationSupport(List items, int ks"|}9\%<
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totalCount){ R,gR;Aarw
setPageSize(PAGESIZE); .}&`TU
setTotalCount(totalCount); ^]7}YF2|
setItems(items); 0vFD3}~>
setStartIndex(0); OSlvwH%(EE
} <nE>XAI_7
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public PaginationSupport(List items, int +s(HOq)b
@AGn{q
totalCount, int startIndex){ lH-/L(h2
setPageSize(PAGESIZE); 'L
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setTotalCount(totalCount); @GkILFN
setItems(items); _hN\10ydY
setStartIndex(startIndex); `JOOnTenQ
} 1|RANy
os,* 3WO
public PaginationSupport(List items, int 8s"%u )
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totalCount, int pageSize, int startIndex){ iEd\6EZ
setPageSize(pageSize); /h+8A',
setTotalCount(totalCount); oz AS[B6
setItems(items); ^?U!pq-`
setStartIndex(startIndex); {/"2Vk<H8
} !>v2i"
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publicList getItems(){ Id'X*U7Q
return items; Nd`%5%'::
} p!>oo1&
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publicvoid setItems(List items){ k,'L}SK
this.items = items; _(Sa4Vb=Q6
} W{%TlN
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publicint getPageSize(){ f%Ns[S~ r
return pageSize; n1JRDw"e$$
} q;QbUO
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publicvoid setPageSize(int pageSize){ {6"Ph(I1
this.pageSize = pageSize; "{tg8-a4)
} H$@`,{M629
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publicint getTotalCount(){ |o{:ZmzM
return totalCount; /`f^Y>4gD
} B-.gI4xa
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publicvoid setTotalCount(int totalCount){ ]e^c=O`$
if(totalCount > 0){ }R1<
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this.totalCount = totalCount; s>0't
int count = totalCount / )f}YW/'
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pageSize; }!;s.[y
if(totalCount % pageSize > 0) ?3%`bY+3;
count++; _9JhL:cY
indexes = newint[count]; cV 5CaaL
for(int i = 0; i < count; i++){ 6I1,:nLL<
indexes = pageSize * )=5ng-
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} /4c\K-Z;
}else{ :,Pn3xl
this.totalCount = 0; VTG9$rQZ
} ]F; f`o
} 3D`YZ#M
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publicint[] getIndexes(){ CZ(/=3,3n
return indexes; gUxP>hB
} 7]9
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publicvoid setIndexes(int[] indexes){ D[^m{ 9_
this.indexes = indexes; G>wqt@%r9
} %K\?E98M
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publicint getStartIndex(){ :Qumb
return startIndex; an|x$e7|?
} 0Uz\H0T1
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publicvoid setStartIndex(int startIndex){ c}y [[EX
if(totalCount <= 0) /h*>P:i].
this.startIndex = 0; jJuW-(/4[
elseif(startIndex >= totalCount) et,f_fd7v
this.startIndex = indexes r.#t63Rb
y>72{
[indexes.length - 1]; bKrhIU[
elseif(startIndex < 0) t*>R`,j
this.startIndex = 0; |`lzfe
else{ kMtwiB|7j
this.startIndex = indexes :lB=Lr)
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[startIndex / pageSize]; (xVsDAp=@
} uoHNn7 W
} s<oNE)xe
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publicint getNextIndex(){ COW}o~3-4
int nextIndex = getStartIndex() + dl~%MWAVb
oo=Qt(#
pageSize; ai
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if(nextIndex >= totalCount) ow_djv:,
return getStartIndex(); =dII- L=`
else B>GE9y5
return nextIndex; Z00+!Tnd
} H&]gOs3So
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publicint getPreviousIndex(){ Td G!&:>
int previousIndex = getStartIndex() - pek%08VSEU
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pageSize; q|8{@EMT
if(previousIndex < 0) czm&~n6$
return0; (cN}Epi(D
else df
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return previousIndex; wg0 \_@3
} |fSe>uVZ
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} QF&W`c
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抽象业务类
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java代码: tl><"6AIP
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/** :%sXO
* Created on 2005-7-12 I('Un@hS
*/ cCa|YW^j
package com.javaeye.common.business; z,VD=Hnz
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import java.io.Serializable; XK: 9r{r{
import java.util.List; ~_s{0g]B
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import org.hibernate.Criteria; Y_]De3:V0B
import org.hibernate.HibernateException; JB>b`W9
import org.hibernate.Session; #(1j#\
import org.hibernate.criterion.DetachedCriteria; bzvh%RsW
import org.hibernate.criterion.Projections; .VkbYK
import C#H:-Q&
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org.springframework.orm.hibernate3.HibernateCallback; v*9<c{a
import /__PSK
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org.springframework.orm.hibernate3.support.HibernateDaoS 4WE6fJ2X
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upport; Zr-U&9.`
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import com.javaeye.common.util.PaginationSupport; eQVZO>)P1+
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public abstract class AbstractManager extends l/Vo-#
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HibernateDaoSupport { |,aG%MTL
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privateboolean cacheQueries = false; Nx-uQ^e*1
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privateString queryCacheRegion; sg8/#_S1i
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publicvoid setCacheQueries(boolean b9"jtRTdz
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cacheQueries){ /RyR>G!
this.cacheQueries = cacheQueries; de]z T^&C
} Ed:eGm }
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publicvoid setQueryCacheRegion(String J-ePE7i
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queryCacheRegion){ (708H_
this.queryCacheRegion = dVQ-k
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queryCacheRegion; "7v-`i
} KE1ao9H8wR
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publicvoid save(finalObject entity){ ||zb6|7I4
getHibernateTemplate().save(entity); ;r/;m\V
} tV9LD>3
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publicvoid persist(finalObject entity){ e;GU
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getHibernateTemplate().save(entity); $HG}[XD?
} {} Bf
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publicvoid update(finalObject entity){ huudBc
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getHibernateTemplate().update(entity); [Px'\nVf
} JxjI]SF02
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publicvoid delete(finalObject entity){ hfcIvs/!
getHibernateTemplate().delete(entity); h C=:q
} ?k[p<Uo
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publicObject load(finalClass entity, 1 ^g
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finalSerializable id){ jEz+1Nl)
return getHibernateTemplate().load $DBGLmw
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(entity, id); ^2odr \
} #,(sAj
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publicObject get(finalClass entity, J!ntXF
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finalSerializable id){ I =Wc&1g
return getHibernateTemplate().get <P%}|@
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(entity, id); }]UB;id'
} qW_u
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publicList findAll(finalClass entity){ c~<1':
return getHibernateTemplate().find("from JIO$=+p
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" + entity.getName()); wzjU,Mwe
} %OcGdbs
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publicList findByNamedQuery(finalString "k$JP
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namedQuery){ DZ
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return getHibernateTemplate jx_4B%kzq
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().findByNamedQuery(namedQuery); P
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} \nrP$
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publicList findByNamedQuery(finalString query, vOI[Z0Lq9h
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finalObject parameter){ k /EDc533d
return getHibernateTemplate smAC,-6]~
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().findByNamedQuery(query, parameter); ,je`YEC
} Ek.&Sf$cd'
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publicList findByNamedQuery(finalString query, }UyQ# U
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finalObject[] parameters){ H ;@!?I
return getHibernateTemplate -[#n+`M
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().findByNamedQuery(query, parameters); ;@4H5p
} ? S=W&
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publicList find(finalString query){ q(z7~:+qNr
return getHibernateTemplate().find J>S3sP
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(query); FY;+PY@I{
} t)1phg4H)
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publicList find(finalString query, finalObject Db03Nk>#
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parameter){ Aa(<L$e!`
return getHibernateTemplate().find 1IA5.@G:
e 3@x*XI
(query, parameter); Q2'eQ0W{o
} H"YL
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public PaginationSupport findPageByCriteria oFg'wAO.
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(final DetachedCriteria detachedCriteria){ M23&<}Q8
return findPageByCriteria =&NOHT>
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); f~gSJ<t4
} J1 tDO?
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public PaginationSupport findPageByCriteria ua& @GXvZ
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(final DetachedCriteria detachedCriteria, finalint C-#.RI7
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startIndex){ }$)&{d G
return findPageByCriteria co]Gmg6p
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(detachedCriteria, PaginationSupport.PAGESIZE, =P_fv
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startIndex); kEAhTh&g*
} wu^q`!ml
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public PaginationSupport findPageByCriteria q) _r3
r{ "uv=,`
(final DetachedCriteria detachedCriteria, finalint i[=C_+2
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pageSize, (v;A'BjN
finalint startIndex){ (t74a E pi
return(PaginationSupport) i<:p.ug-O
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getHibernateTemplate().execute(new HibernateCallback(){ B! `\L!
publicObject doInHibernate :@e\'~7sH
{,v:
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(Session session)throws HibernateException { 0WS|~?OR@
Criteria criteria = 5&%fkZ0
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detachedCriteria.getExecutableCriteria(session); .\4l'THn,0
int totalCount = 9RcM$[~
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((Integer) criteria.setProjection(Projections.rowCount [D9 :A
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()).uniqueResult()).intValue(); y*|L:!
criteria.setProjection
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(null); C,='3^Nc
List items = u2,H ]-
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criteria.setFirstResult(startIndex).setMaxResults TPqvp|~2
w=$'Lt!
(pageSize).list();
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PaginationSupport ps = L`pY27|
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new PaginationSupport(items, totalCount, pageSize, .]zw*t*
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startIndex); UC;=)
return ps; N=<=dp(
} nO}$ 76*'0
}, true); F%y{%
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} PuU*vs3
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public List findAllByCriteria(final (6o:4|xl0
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DetachedCriteria detachedCriteria){ d{l{P]nr
return(List) getHibernateTemplate +|M{I= 8
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().execute(new HibernateCallback(){ TL]bY'%
publicObject doInHibernate _4Ii5CNNU
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(Session session)throws HibernateException { m"q/,}DR
Criteria criteria = uh1S
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detachedCriteria.getExecutableCriteria(session); wU.'_SBfB
return criteria.list(); M!-q}5' ;
} :` ;(p{
}, true); ^} tLnF
} G6<HO7\
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public int getCountByCriteria(final S>(z\`1qm
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DetachedCriteria detachedCriteria){ hO%Y{Gg
Integer count = (Integer) +fkP+RVY
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getHibernateTemplate().execute(new HibernateCallback(){ SC]6F*
publicObject doInHibernate .$UTH@;7
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(Session session)throws HibernateException { sK#H4y+<
Criteria criteria = /%-o.hT
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detachedCriteria.getExecutableCriteria(session); l<s :%%CX
return QXsfp
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criteria.setProjection(Projections.rowCount #&}%70R)
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()).uniqueResult(); +yt 6.L
} bJANZn|H
}, true); w4NZt|>5j;
return count.intValue(); Z4=_k{*
} sYl&Q.\q
} )iT.A
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用户在web层构造查询条件detachedCriteria,和可选的 MacL3f
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 w2.qT+;v
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PaginationSupport的实例ps。 9NJ=~Ub-
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ps.getItems()得到已分页好的结果集 l_UXrnm/N
ps.getIndexes()得到分页索引的数组 R~U2/6V
ps.getTotalCount()得到总结果数 Sn;/;^@(\
ps.getStartIndex()当前分页索引 @hE7r-}]
ps.getNextIndex()下一页索引 40`9t Xn
ps.getPreviousIndex()上一页索引 aa%Yk"V@
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 okd
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 S-H-tFy\\
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一下代码重构了。 V\e13cL]
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我把原本我的做法也提供出来供大家讨论吧: e<ism?WG
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首先,为了实现分页查询,我封装了一个Page类: [|c@Yw
java代码: ~ wJ3AqNC?
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/*Created on 2005-4-14*/ yg-L^`t+B5
package org.flyware.util.page; ifgr<QlG
< e7<t9
/** ZC9.R$}Kl
* @author Joa ;r0|_mnf
* V PLCic,T
*/ O>tC]sm%
publicclass Page { aHVdClD2o
m=("N
/** imply if the page has previous page */ }
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privateboolean hasPrePage; >yPFL'
X*c_^g{
/** imply if the page has next page */ FBwncG$]F*
privateboolean hasNextPage; Jm*M7gj
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/** the number of every page */ 5pKvNLy.t
privateint everyPage; 5* o\z&*L
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/** the total page number */ uZ=UBir
privateint totalPage; %FR^[H]
:<WQ;q
/** the number of current page */ 6Mf3)o2
privateint currentPage; &ttv4BC^r
*]E7}bqb
/** the begin index of the records by the current N8MlT \+r
7KSGG1ts
query */ x(/@Pt2B
privateint beginIndex; =|WV^0=S'%
/v;)H#;
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/** The default constructor */ 5E oWyy
public Page(){ mC[U)` ey
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} L->f=
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5w [=
/** construct the page by everyPage ,Dii?P
* @param everyPage zcD_}t_K
* */ rJc)<OZjT
public Page(int everyPage){ ;MRC~F=
this.everyPage = everyPage; l
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} dD.d?rnZq7
^ yukn*L
/** The whole constructor */ C +?@iMh
public Page(boolean hasPrePage, boolean hasNextPage, cLyuCaH>c
T
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int everyPage, int totalPage, |C)UZ4A/p
int currentPage, int beginIndex){ `d|bH;w
this.hasPrePage = hasPrePage; r)#"$Sm
this.hasNextPage = hasNextPage; :@@A
this.everyPage = everyPage; <%3SI.
this.totalPage = totalPage; j_a~)o-p
this.currentPage = currentPage; h3d\MYO)B
this.beginIndex = beginIndex; ZAM+4#@
} 72`/xryY
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/** % 6hw
* @return "k1Tsd-
* Returns the beginIndex. ~~:8Yv[(
*/ ,pa&he
publicint getBeginIndex(){ QH' [(
return beginIndex; !E:Vn *k;
} xE-c9AH
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/** 3
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* @param beginIndex b;{"lJ:+Z
* The beginIndex to set. ;7n*PBUJJ
*/ j]l}K*8(
publicvoid setBeginIndex(int beginIndex){ -J7,Nw
this.beginIndex = beginIndex; 7fTg97eF
}
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/** b}L,kT
* @return )4_6\VaM
* Returns the currentPage. 8~Hs3\Hp
*/ Q%VR@[`\
publicint getCurrentPage(){ (DMnwqr
return currentPage; Fx99"3`3
} l
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Vv)E41
/** 5F sj_wFk
* @param currentPage ODvpMt:+
* The currentPage to set. ^}7t:
*/ D:vUy*
publicvoid setCurrentPage(int currentPage){ F4<2.V)#-
this.currentPage = currentPage; |wb(rua
} *n_4Rr
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/** d~Ry>
* @return y^46z(I
* Returns the everyPage. TIhzMW\/K
*/ ,Y8X"~{A
publicint getEveryPage(){ ZpctsCz]
return everyPage; J+NK+,_*M
} 5_C#_=E
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/** /cen#pb
* @param everyPage "jc)N46
* The everyPage to set. FYS83uq0
*/ XK-x*|
publicvoid setEveryPage(int everyPage){ Jv.R?1;8i
this.everyPage = everyPage; *>$)#?t
} @CI6$
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/** eniR}
* @return LhRe?U\
* Returns the hasNextPage. $cU/Im`
*/ K/+C6Y?
publicboolean getHasNextPage(){ `80Hxp@
return hasNextPage; TPFmSDq
} i O|,,;_
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/** r+pjv_R
* @param hasNextPage ;O|63
* The hasNextPage to set. z35Rjhj9
*/ n1(X%%2
publicvoid setHasNextPage(boolean hasNextPage){ N4jLbnA
this.hasNextPage = hasNextPage; 8~#Q *
} 6|cl`}g_j
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/** 7zZ|=W?&{
* @return oa !P]r
* Returns the hasPrePage. ^(vd8 &71
*/ S]=Vr%irX
publicboolean getHasPrePage(){ 1tz .e\
return hasPrePage; Vp{2Z9]}
} Z@/5~p
Hvo27THLo
/** nW'x#0-
* @param hasPrePage pPpnO
* The hasPrePage to set. C
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*/ y<d#sv(s
publicvoid setHasPrePage(boolean hasPrePage){ o|q#A3%?
this.hasPrePage = hasPrePage; Ib2pV2`h(
} VW`=9T5%@
uI&M|u:nT
/** Z"+!ayA7D
* @return Returns the totalPage. rNyK*Wjt
* {?hjx+v[
*/ R,1 ,4XT
publicint getTotalPage(){ j~q`xv+R
return totalPage; F|Q#KwN
} h
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c iX2G
/** &[5az/Hj*
* @param totalPage NLY5L7
* The totalPage to set. ayp}TYh*
*/
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publicvoid setTotalPage(int totalPage){ 5K{h)* *5
this.totalPage = totalPage; `Cxe`w4
} K^\9R
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} =YIQ
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]
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f
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 W$S.?[X
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个PageUtil,负责对Page对象进行构造: 6<Z9p@6
java代码: ,RQ-w2j?
)K~nZLULY
hgGcUpJy?
/*Created on 2005-4-14*/ 7i.aZ2a%
package org.flyware.util.page; 5Y^YKV{
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import org.apache.commons.logging.Log; \.]
U
import org.apache.commons.logging.LogFactory; LKcrr;
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/** 4NV1v&"
* @author Joa QUf_fe!,|
* c&&UT-Z
*/ 'oG'`ED"
publicclass PageUtil { Xl;N=fc
Ek3O{<
privatestaticfinal Log logger = LogFactory.getLog ^iNR(cwgX
{NR~>=~K-
(PageUtil.class);
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/** CR<l"~X
* Use the origin page to create a new page srL,9)OC
* @param page A7H=#L+C
* @param totalRecords X*KT=q^?n
* @return x%1Rp[
*/ #Z : r
publicstatic Page createPage(Page page, int
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:[doYizk:
totalRecords){ ^d,d<Uc
return createPage(page.getEveryPage(), #7{a~-S
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page.getCurrentPage(), totalRecords);
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} Sc&_6}K
h(BN6ZrzKd
/** eW/Hn
* the basic page utils not including exception F~EriO
SPBXI[[-
handler R-ci?7d t3
* @param everyPage 6o!"$IH4
* @param currentPage HM/ qB^
* @param totalRecords 4"{q|~&=:$
* @return page eX\t]{\oC
*/ ZYG"nmNd
publicstatic Page createPage(int everyPage, int |c)#zSv
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currentPage, int totalRecords){ OX91b<A
everyPage = getEveryPage(everyPage); =$MV3]
currentPage = getCurrentPage(currentPage); "='|c-x
int beginIndex = getBeginIndex(everyPage, ]Sh&8 #
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currentPage); <iMLM<J<w
int totalPage = getTotalPage(everyPage, F)C8LH
ipsNiFv:
totalRecords); 6 `'^$wKs
boolean hasNextPage = hasNextPage(currentPage, K|iNEhuc
\-^3Pe,
totalPage); kns[b [!H
boolean hasPrePage = hasPrePage(currentPage); 3'8~H]<W
`| fF)kI
returnnew Page(hasPrePage, hasNextPage, r_)*/
everyPage, totalPage, X]N8'Yt
currentPage, BzDS
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beginIndex); {2!.3<#
} !$j'F? 2>
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privatestaticint getEveryPage(int everyPage){ <3i!{"}
return everyPage == 0 ? 10 : everyPage; !+i
} dme_Ivt
|KuH2,n0
privatestaticint getCurrentPage(int currentPage){
8$1<N
return currentPage == 0 ? 1 : currentPage; ^+-i7`|=
} VP[ J#TPU
'C(YUlT2?P
privatestaticint getBeginIndex(int everyPage, int nfc&.(6x<
`Do-!G+W
currentPage){ q?`bu:yS
return(currentPage - 1) * everyPage; 1Eh(U
} a4c~ThbI
X[R/j*K
privatestaticint getTotalPage(int everyPage, int W}Z'zU?[
t'^/}=c-
totalRecords){ Nx~8]h1(
int totalPage = 0; 8xLvpgcZ
1%H]2@
if(totalRecords % everyPage == 0) z`lDD
totalPage = totalRecords / everyPage; %{axoGd
else ^dQ#\uy
totalPage = totalRecords / everyPage + 1 ; XJGOX
n$/
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return totalPage; gE|_hfm(
} TC'tui
rlgp1>89
privatestaticboolean hasPrePage(int currentPage){ 2-FL&DE
return currentPage == 1 ? false : true; fVw+8 [d0
} Tw=Jc 's
L9"V$MO
privatestaticboolean hasNextPage(int currentPage, OQA}+XO
Yz4Q!tL
int totalPage){ tQF,E&Jo8
return currentPage == totalPage || totalPage == 6Z0@4_Y@B6
=
oQ-I
0 ? false : true; PE0A `
} USv: +
.
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QYPsqkF*
} J;HkR9<C
>2TDYB|;
`$7.(.#s
oIN!3
eNR>W>;'
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 |#>\GU=!
o[X'We;
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 HTAJn_
2Gd.B/L6
做法如下: :2vk
vLM
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 W{<_gD9
N*y09?/h
的信息,和一个结果集List: k?ZtRhPu3X
java代码: ,3 =|a|p
>+ulLQqe
/_rEI,[k
/*Created on 2005-6-13*/ hCS|(8g
package com.adt.bo; BIqZg$
dI};l
import java.util.List; qj/
pd
7\
cks53/Z
import org.flyware.util.page.Page; 5)bf$?d
&@NTedg!
/** LlKvi_z
* @author Joa e)"]H*
*/ }coSMTMv6
publicclass Result { N8S!&*m
X: PB
}
private Page page; [$:M/5y9
M$iDaEu-
private List content; 2O;Lw@W
>zx]%
W
/** qz[qjGdHg
* The default constructor J)tk<&X
*/ iYJ: P
public Result(){ ~QzUQYG*
super(); t+y$i@R:
} J'{69<`Dl
JWQd/
/** DD5S
R
* The constructor using fields ,t?c=u\5
* xgeDfpF'
* @param page g2)jd[GM
* @param content cC@.&
*/ +pMa-{
public Result(Page page, List content){
/,Unp1D
this.page = page; 2yB)2n#ut
this.content = content; [=/Yo1:v
} n/]w!
Qg9*mlm`
/** *S _[8L"
* @return Returns the content. ,yPs4',d
*/ {p.D E
publicList getContent(){ 10.u
return content; i*ibx;s-
} NWL\"xp
`t
cl\Gh
/** ''.P=
* @return Returns the page. 4S9hz
*/ R k'5L
public Page getPage(){ "p Rr>F a
return page; ^lw0}
i
} .C HET]
l rRRRR
/** r [NI#wW
* @param content $!Qv f
* The content to set. *;N6S~_'Y
*/ NCu:E{([
public void setContent(List content){ 0;J#".(KQ
this.content = content; 8,VX%CS#q
} ` @PHV
<q}w, XU
/** 44r@8HO1
* @param page 5>S=f{ghFw
* The page to set. @Yzdq\FI
*/ An.Qi =Cv
publicvoid setPage(Page page){ h=a-~= 8
this.page = page;
xY_<D+OV
} \jR('5DcB
} JkfVsmc<{h
b '9L}q2m
@gc|Z]CV
DTx!# [
- WEEnwZ
2. 编写业务逻辑接口,并实现它(UserManager, C<G`wXlP|
\gU=B|W
UserManagerImpl) 178u4$# b
java代码: J$+K't5BZ
Hyn* O)q!
",O}{z
/*Created on 2005-7-15*/ g %e"K nU
package com.adt.service; U
%,K8u|WH
s7
K](T4
import net.sf.hibernate.HibernateException; L_~vPp
Ho^rYz
import org.flyware.util.page.Page; E0lro+'lS
qX_(
M2oLU
import com.adt.bo.Result; o$XJSz|6
RZL:k;}5
/** Q>QES-.l
* @author Joa _v\L'`bif
*/ wI{ED
publicinterface UserManager { gX'nFGqud
tqMOh R
public Result listUser(Page page)throws =7l'3z8
_oU}>5
HibernateException; lk[BS*
S!J wF&EW
} 7j//x Tr}a
p]^?4
PKK18E}{%^
cy%S5Rz
I5$]{:L|9
java代码: >P_/a,O8
M[}aQWT$v
h,Nq:"}
/*Created on 2005-7-15*/ Up*.z\|'y
package com.adt.service.impl; h+"UK=
caC-JcDXy
import java.util.List; S+mM S
PSR21;
import net.sf.hibernate.HibernateException; e^ ZxU/e
3mCf>qj73
import org.flyware.util.page.Page; s<hl>vY_'
import org.flyware.util.page.PageUtil; )_-EeH
#ts;s\!
import com.adt.bo.Result; D>>?8a
import com.adt.dao.UserDAO; ?ZS/`P0}[
import com.adt.exception.ObjectNotFoundException; #J_+
SL[
import com.adt.service.UserManager; lq[o2\
+Dwq>3AH
/** ZPO+ #,
* @author Joa (h$[g"8
*/ w /l\p3n
publicclass UserManagerImpl implements UserManager { \]7i-[
r}%2;!T
private UserDAO userDAO; k&M9Hn2
n5e1ky*9w
/** -rXo}I,VI
* @param userDAO The userDAO to set. J4VyP["m
*/ EH2a
publicvoid setUserDAO(UserDAO userDAO){ TTQ(\l4
this.userDAO = userDAO; $6Az\Iu *
} S`?L\R.:
6vL+qOd x
/* (non-Javadoc) N{<9Njmm
* @see com.adt.service.UserManager#listUser //O9}-
7sglqf>
(org.flyware.util.page.Page) VQe@H8>3
*/ H-ewO8@
public Result listUser(Page page)throws t,4'\nv*
%'vLkjI.
HibernateException, ObjectNotFoundException { |(Q !$
int totalRecords = userDAO.getUserCount(); "eOFp\vPr
if(totalRecords == 0) hY5tBL
throw new ObjectNotFoundException hxX-iQya
23_\UTM}1
("userNotExist"); [/'=M h
page = PageUtil.createPage(page, totalRecords); l<"Z?z
List users = userDAO.getUserByPage(page); )&$p?kF
returnnew Result(page, users); Sb,lY<=
} ?x-:JME0
xmp^`^v*
}
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zmdu\:_X9
s^6"qhTa
hO H
DXc"
ZBcT@hxm
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 GDBxciv
*B ]5K{N
询,接下来编写UserDAO的代码: q(iM=IeiN
3. UserDAO 和 UserDAOImpl: uL1$yf'
java代码: FXd><#U
ZlEH3-Zv
;VlA~tv
/*Created on 2005-7-15*/ Zwm2T3@e
package com.adt.dao; 9EI Oa/*
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import java.util.List; %"{jNC?
o n+:{ad
import org.flyware.util.page.Page;
,R8:Y*@P
8O='Q-&8
import net.sf.hibernate.HibernateException; ^9wQl!e
ob
#G`UR
/** IP3%'2}-
* @author Joa ;wF 0s
*/ n(.U>_
P
publicinterface UserDAO extends BaseDAO { *~H\#N|x
BL?Bl&p(
publicList getUserByName(String name)throws oBqWIXM
hantGw|
HibernateException; //W7$DYEG
LRa^x44
publicint getUserCount()throws HibernateException; kEr;p{5
ehe;<A
publicList getUserByPage(Page page)throws d>OLnG>
F
wr+r J
HibernateException; [n!5!/g>j
x.ZW%P1
} [8OQ5}do/
@}[yC['
\u@*FTS
Z#nPn>,q
M,V~oc5
java代码: d} {d5-_a
ytkV"^1^
|'?./
/*Created on 2005-7-15*/ 'Bc{N^
package com.adt.dao.impl; <[W41{
Y(D&JKx
import java.util.List; }>T$2"pf
yR|Beno
import org.flyware.util.page.Page; |:jka
:#I7);ol
import net.sf.hibernate.HibernateException; Q(gc(bJV
import net.sf.hibernate.Query; ^xZ o.P
g4"0:^/
import com.adt.dao.UserDAO; +&j