Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 wA}+E)x/C
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 VIxcyp0X
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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 /P|jHK|{
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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 #VEHyz 6P
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分页支持类: P1ab2D
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java代码: R#Bdfmldq
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package com.javaeye.common.util; .r?-O{2t
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import java.util.List; ]f q.r
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publicclass PaginationSupport { xAD: Z"
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publicfinalstaticint PAGESIZE = 30; BS;_l"?
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privateint pageSize = PAGESIZE; ;,]T|>M
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privateList items; i4N'[ P}
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privateint totalCount; g%Ap <iT
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privateint[] indexes = newint[0]; <gKT 7ONtg
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privateint startIndex = 0; Hs8c%C
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public PaginationSupport(List items, int ,!3G
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totalCount){ :d-+Z%Y
setPageSize(PAGESIZE); ND7
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setTotalCount(totalCount); A|8(3PiP
setItems(items); ^l6q
setStartIndex(0); ?y7x#_Exc
} W9T,1h5x
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public PaginationSupport(List items, int kQ~*iY
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totalCount, int startIndex){ BXVmt!S5F
setPageSize(PAGESIZE); D`LcL|nmH
setTotalCount(totalCount); ,.uPlnB_
setItems(items); CC>]Gc7
setStartIndex(startIndex); wg*2mo
} },'2j
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public PaginationSupport(List items, int ajW[}/)
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totalCount, int pageSize, int startIndex){ ^'~+ w3M@
setPageSize(pageSize); }}v;V*_V
setTotalCount(totalCount); [|\~-6"7N|
setItems(items); 8|`4D 'Ln
setStartIndex(startIndex); jnX9] PkJ
} )G0a72
iU\WV
publicList getItems(){ %J?;@ G)r
return items; |?SK.1pW
} -U(T
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publicvoid setItems(List items){ |Gb"%5YD
this.items = items; <DCrYt!1}c
} :grJ}i-D
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publicint getPageSize(){ u~6`9'Ms
return pageSize;
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} }.O2xZ;}]'
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publicvoid setPageSize(int pageSize){ hV/$6 8A_
this.pageSize = pageSize; 7^h?<X\
} *Y6BPFE*4
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publicint getTotalCount(){ =m=`| Bn
return totalCount; !12W(4S5
} H~1*`m
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publicvoid setTotalCount(int totalCount){ ^S'}RZ*>
if(totalCount > 0){ ;GO>#yg4Eh
this.totalCount = totalCount; s2Ivd*=mT
int count = totalCount / veg\A+:'
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pageSize; ~fn2B
if(totalCount % pageSize > 0) %8tlJQvu
count++; vAi
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indexes = newint[count]; T@uY6))>F
for(int i = 0; i < count; i++){ <SUjz}_Oa:
indexes = pageSize * l
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}
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}else{ [nxjPx9-
this.totalCount = 0; <*~vZT i(
}
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} xXM`f0s@+]
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publicint[] getIndexes(){ )Fk%,H-1
return indexes; `9Zoq=/
} 9`+c<j4/B
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publicvoid setIndexes(int[] indexes){ I|,^a|\
this.indexes = indexes; B5aFt ;Vj
} 8'_>A5L/C
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publicint getStartIndex(){ sXkWs2!
return startIndex; 9 W><m[O
} 7\'vSHIL
@;M( oFS9
publicvoid setStartIndex(int startIndex){ 9~bje^M
if(totalCount <= 0) g= k}6"F~
this.startIndex = 0; i2/:'
i
elseif(startIndex >= totalCount) .{LFc|Z[
this.startIndex = indexes yv^j~
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[indexes.length - 1]; G eN('0
elseif(startIndex < 0) qi_[@da f?
this.startIndex = 0; {BKu'A
else{ 33DP0OBL^
this.startIndex = indexes ZFNM>C^
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[startIndex / pageSize]; ]fIv{[A_
} \T'uFy9&a
} 11}X2j~Ww
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publicint getNextIndex(){ Pfu2=2Ra
int nextIndex = getStartIndex() + }x`W+r
L"A,7@:Vd
pageSize; g8
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if(nextIndex >= totalCount) RyKsM.
return getStartIndex(); kXA
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else aErms-~
return nextIndex; 4<)%Esyb
} aG}ju;
: I28Zi*
publicint getPreviousIndex(){ ao#{N=mn
int previousIndex = getStartIndex() - >xws
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pageSize; ByoSwQ
if(previousIndex < 0) }(z[
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return0; 6uW?xB9
else N%%2!Z#
return previousIndex; ;ajCnSmR
}
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} ;BUJ5
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抽象业务类 G1 z[v3T
java代码: $Mm=5K%
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/** O%;H#3kn&s
* Created on 2005-7-12 %eB 0)'
*/ F0W4B
package com.javaeye.common.business; S:4'k^E
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import java.io.Serializable; lfp[(Ph)9
import java.util.List; MWl?pG!Y
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import org.hibernate.Criteria; IL` X}=L_
import org.hibernate.HibernateException; J^8(h R
import org.hibernate.Session; :0x,%V74_!
import org.hibernate.criterion.DetachedCriteria; e3,TY.,Ay
import org.hibernate.criterion.Projections; -U~]Bugvh
import xDv$z.=Y
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org.springframework.orm.hibernate3.HibernateCallback; [74HUw>
import c""*Ng*T
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org.springframework.orm.hibernate3.support.HibernateDaoS =/Pmi_
v=e`e68U~
upport; mIgc)"
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import com.javaeye.common.util.PaginationSupport; {I0b%>r=
*F0O*n*7W
public abstract class AbstractManager extends g*?)o!_*
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HibernateDaoSupport { )zz^RB\p
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privateboolean cacheQueries = false; (? j $n?p
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privateString queryCacheRegion; yH5^EY7rQ
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publicvoid setCacheQueries(boolean e f8_w6i
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cacheQueries){ vaN}M)W/
this.cacheQueries = cacheQueries; 2(M^8Bl
} S`g:zb_
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publicvoid setQueryCacheRegion(String &<hDl<E
,(&jG^IpVJ
queryCacheRegion){ )@+lfIE(l
this.queryCacheRegion = VWDXEa9
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queryCacheRegion; Otq`4 5
} QP/%+[E.
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publicvoid save(finalObject entity){ +c;/hM<IX.
getHibernateTemplate().save(entity); ^*JpdmVhu
} C_xOk'091
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publicvoid persist(finalObject entity){ ;^+#
getHibernateTemplate().save(entity); qYo"-D*
} mG4$
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publicvoid update(finalObject entity){ ETU.v*HT]
getHibernateTemplate().update(entity); {p3VHd#
} /]7FX"
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publicvoid delete(finalObject entity){ {6H%4n
getHibernateTemplate().delete(entity); K5l#dl_T
} [O~'\Q
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publicObject load(finalClass entity, :lf;CT6$
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finalSerializable id){ ~DY5`jV
return getHibernateTemplate().load d'j8P
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(entity, id); OS|uZ<"Rq3
} '2)c;/-E
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publicObject get(finalClass entity, fzcPi9+
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finalSerializable id){ V.<$c1#=$
return getHibernateTemplate().get >JdA,i}1
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(entity, id); C- 25\
} )gM3,gSS
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publicList findAll(finalClass entity){ ;/tZsE{
return getHibernateTemplate().find("from ?naPti1GX
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" + entity.getName()); 5vxKkk&i4l
} !%w#h0(b
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publicList findByNamedQuery(finalString VjZ_L_U}
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namedQuery){ g~q+a-
return getHibernateTemplate DGfhS` X
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().findByNamedQuery(namedQuery); *Nfn6lVB
} %cIF()
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publicList findByNamedQuery(finalString query, 2kv%k3Q{
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finalObject parameter){ kk`BwRh)d;
return getHibernateTemplate , $;g'z!N
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().findByNamedQuery(query, parameter); $^&SEz
} _W@SCV)yH
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publicList findByNamedQuery(finalString query, 3,`.$
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finalObject[] parameters){ iQ[0d.(A
return getHibernateTemplate 9C$#A +~C
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().findByNamedQuery(query, parameters); qg7]
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} 79.J`}#
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publicList find(finalString query){ w1zI"G~4/Q
return getHibernateTemplate().find |.bp
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(query); >{DHW1kF?
} fVR:m`'Iq_
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publicList find(finalString query, finalObject $}[Tj0+:
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parameter){ Salu[)+?
return getHibernateTemplate().find [\9WqHs
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(query, parameter); Bx(+uNQ
} !U02>X
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public PaginationSupport findPageByCriteria Kd_WN;l
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(final DetachedCriteria detachedCriteria){ S}"?#=Q.%O
return findPageByCriteria niO(>
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); "Y&+J@]
} vPG!S{4
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public PaginationSupport findPageByCriteria >K`.!!av,Y
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(final DetachedCriteria detachedCriteria, finalint oz}p]l7
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startIndex){ Z2chv,SqCJ
return findPageByCriteria FswMEf-|
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(detachedCriteria, PaginationSupport.PAGESIZE, v{rc5 ]\R
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startIndex); >Kl78w:
} -X#J<u T/
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public PaginationSupport findPageByCriteria ^H+j;K{5,
@LY 5]og
(final DetachedCriteria detachedCriteria, finalint ~A0E4UJgq
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pageSize, ;(w=}s%]+
finalint startIndex){ `w Sg/
return(PaginationSupport) Q, E!Ew3
`
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getHibernateTemplate().execute(new HibernateCallback(){ zIbl[[M&
publicObject doInHibernate /,v:!*
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(Session session)throws HibernateException { }nE#0n
Criteria criteria = )Jx!VJ^Y
@ ADY?
detachedCriteria.getExecutableCriteria(session); u)P$xkf
int totalCount = +DKrX
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((Integer) criteria.setProjection(Projections.rowCount ^F*)Jq
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()).uniqueResult()).intValue(); Zn3iLAPBX
criteria.setProjection QnxkD)f*0
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(null); K/[v>(<
List items = 4~a0
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criteria.setFirstResult(startIndex).setMaxResults \3q{E",\>@
m@JU).NKCS
(pageSize).list(); !W:QLOe6F
PaginationSupport ps = :kZ2N67
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new PaginationSupport(items, totalCount, pageSize, 5*buRYck0
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startIndex); =Ak>2
return ps; v85&s
} :&)RK~1m_
}, true); B^Ql[m&5+
} 62EJ# q[
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public List findAllByCriteria(final mC~W/KReA
c%~'[W04\
DetachedCriteria detachedCriteria){ {yyg=AMz
return(List) getHibernateTemplate C>68$wd>
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().execute(new HibernateCallback(){ |ry;'[*
publicObject doInHibernate U7crbj;c)d
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(Session session)throws HibernateException { O8u"Y0$*w
Criteria criteria = 2|}p&~G(
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detachedCriteria.getExecutableCriteria(session); y8+?:=N.
return criteria.list(); lRt8{GFy
} 4)j<(5
}, true); ]^
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} ZuS+p0H"
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public int getCountByCriteria(final SO p%{b
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DetachedCriteria detachedCriteria){ M`?/QU~
Integer count = (Integer) LR)is
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getHibernateTemplate().execute(new HibernateCallback(){ f `Wfw3
publicObject doInHibernate /HzhgMV3
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(Session session)throws HibernateException { 0^ (.(:
Criteria criteria = U}A+jJ
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detachedCriteria.getExecutableCriteria(session); l"*>>/U k
return He!0&B\7h
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criteria.setProjection(Projections.rowCount #gN{8Yk>
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()).uniqueResult(); 30H:x@='9
} %\b5)p
}, true); 5R ec}H
return count.intValue(); ]hf4= gm
} rz7yAm
} O_iX1@SW
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用户在web层构造查询条件detachedCriteria,和可选的 Ck^= H
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 (u'/tNGS
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PaginationSupport的实例ps。 '\_)\`a|
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ps.getItems()得到已分页好的结果集 T8m%_U#b
ps.getIndexes()得到分页索引的数组 {W4t]Ff
ps.getTotalCount()得到总结果数 {(MG:
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ps.getStartIndex()当前分页索引 1b!l+ 8!
ps.getNextIndex()下一页索引 cEQa 6
ps.getPreviousIndex()上一页索引 AMm O+E?
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 %4-pw|':
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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 U&/S
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一下代码重构了。 @"EX%v.
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我把原本我的做法也提供出来供大家讨论吧:
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首先,为了实现分页查询,我封装了一个Page类: `dNb%f>
java代码: 7>mYD3
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/*Created on 2005-4-14*/ [}Iq-sz;0
package org.flyware.util.page; !'MD8
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/** puyL(ohem
* @author Joa ]a%Kn]HI&2
* [aC9vEso!
*/ ,5?MRqCM
publicclass Page { gc:>HX);)
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93h
/** imply if the page has previous page */ iTvCkb48m
privateboolean hasPrePage; .KSGma6]
<KA@A}
/** imply if the page has next page */ l{AT)1;^
privateboolean hasNextPage; iau&k`b`
5`DH\VD.j
/** the number of every page */ OR9){qP
privateint everyPage; J)->
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FHC7\#p/9Z
/** the total page number */ !;a<E:
privateint totalPage; rY= #^S
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/** the number of current page */ }{y$$X<:
privateint currentPage; BSf"'0I&
u\wd<<I']
/** the begin index of the records by the current iE`aGoA
l :"*]m7o_
query */ M2S|$6t:
privateint beginIndex; yw<xv-Q=i
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/** The default constructor */ ( -@>
public Page(){ Zv\b`Cf}
"!?bC#d#(
} +bnw,B><
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/** construct the page by everyPage OEW,[d
* @param everyPage H/&Q,9sU21
* */ buXG32;
public Page(int everyPage){ ?OyW|jL
this.everyPage = everyPage; (c2\:hvy
}
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/** The whole constructor */ U;@jl?jnG
public Page(boolean hasPrePage, boolean hasNextPage, W|e>
($W 5fbu
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int everyPage, int totalPage, j[cjQ]>~'
int currentPage, int beginIndex){ 1n"X?K5;A
this.hasPrePage = hasPrePage; &L]*]Xz;
this.hasNextPage = hasNextPage; !y?hn$w0
this.everyPage = everyPage; sQs5z~#51*
this.totalPage = totalPage; #^ #i]{g
this.currentPage = currentPage; ZtoE=7K
this.beginIndex = beginIndex; du,-]fF
} y9hZ2iT
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/** R-fjxM*
* @return T7~v40jn|
* Returns the beginIndex. AUde_1hi
*/ |GQ$UB
publicint getBeginIndex(){ |lwN!KVQ,
return beginIndex; JrTBe73.]j
} cx(F,?SbS
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/** oZ[ w
* @param beginIndex 55b |zf
* The beginIndex to set. E |
*/ e~;)-Z
publicvoid setBeginIndex(int beginIndex){ V2%wb\_z
this.beginIndex = beginIndex; qEr[fC@x
}
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/** CD[=z)<z{
* @return
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* Returns the currentPage. :q<%wLs
*/ m4>oE|\
publicint getCurrentPage(){ h_yR$H&tX
return currentPage; S(h*\we
} eE%yo3
_|:bac8pL
/** U&$]?3?
* @param currentPage nV*sdSt
* The currentPage to set. iQC&d_#
*/ *8H;KGe=
publicvoid setCurrentPage(int currentPage){ 9z/_`Xd_
this.currentPage = currentPage; 3uG5b8?
} L.[uMuUa
7`@?3?
/** 0\nhg5]?
* @return g GT,PP(k
* Returns the everyPage. B1#>$"_0}=
*/ Ec*7n6~9
publicint getEveryPage(){ {; cB?II
return everyPage; WC*:\:mh
} e*6` dz@
t>@3RBEK
/** Y'0?<_ fj
* @param everyPage vcU\xk")
* The everyPage to set. 6XK`=ss?
*/ %P,^}h7
publicvoid setEveryPage(int everyPage){ .OS?^\
this.everyPage = everyPage; )}\@BtcjA]
} )ZyuF(C&
!>Y\&zA
/** ]mo<qWRc>p
* @return N:jiZ)
* Returns the hasNextPage. n12c075
*/ P\6T4s
publicboolean getHasNextPage(){ ^GaPpm
return hasNextPage; ~.`r(
} u!Nfoq&'u
V?dK *8s
/** g]
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* @param hasNextPage ^-*Tn
* The hasNextPage to set. ixHZX<6zYT
*/ GiO#1gA
publicvoid setHasNextPage(boolean hasNextPage){ `4$Qv'X*
this.hasNextPage = hasNextPage; ":^
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} i3&B%JiLX
)K%O/H
/** Fd,+(i D
* @return `Mp7})
* Returns the hasPrePage. M#=5u`h
*/ ~2DV{dyj
publicboolean getHasPrePage(){ a;T[%'in
return hasPrePage; y{I[}$k
} }\L!;6oy
yxWMatZ2
/** =,8Eo"~\
* @param hasPrePage b<V./rWIB
* The hasPrePage to set. nEcd+7(
*/ @&xaaqQ-
publicvoid setHasPrePage(boolean hasPrePage){ S@zkoj@
this.hasPrePage = hasPrePage; {2gd4[:
} -Dq:Y,%q
q;0&idYC
/** t:sq*d
* @return Returns the totalPage. :tqm2t
* RHl=$Hm.%
*/ v;}`?@G
publicint getTotalPage(){ [x p,&
return totalPage; !5SQN5K
} )Z]y.W )
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/** u#@{%kPW
* @param totalPage HGQ?(2] 8$
* The totalPage to set. [gns8F#H\
*/ Y0fO.k#C^
publicvoid setTotalPage(int totalPage){ !a&SB*%^I3
this.totalPage = totalPage; #!u51P1
} $EGRaps{j>
V]kGcS}
} u}LX,B-n(
m5em<P!G
]v\egfW,W
j5h
6u,^:
dJ%Rk#?;A
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 xgT~b9
hn\Q6f+
个PageUtil,负责对Page对象进行构造: K_+;"G
java代码: oSA*~ N:
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/*Created on 2005-4-14*/ |~bR.IA
package org.flyware.util.page; DMcxa.Sd!
[kuVQ$)
import org.apache.commons.logging.Log; -6~y$c&c
import org.apache.commons.logging.LogFactory; 1.95 ^8
eBC%2TF
/** ZecvjbnVY
* @author Joa 9+8!xwR:
* Z-h7
*/ +5t
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publicclass PageUtil { 7Cd_zZ
uQu/(5
privatestaticfinal Log logger = LogFactory.getLog ^L-w(r62<
#;"D)C
(PageUtil.class); :IR9=nhS]
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/** yB4H3Q )
* Use the origin page to create a new page *fH_lG%
* @param page pba8=Z
* @param totalRecords 7.e7Fi{
* @return <ql w+RVt
*/ m&`(pf4A
publicstatic Page createPage(Page page, int 4OOn, 09
<{cNgKd9
totalRecords){ bH\C5zt6(
return createPage(page.getEveryPage(), mYh5#E41J
%`?;V;{=
page.getCurrentPage(), totalRecords); ?)'
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} 9XoQO 9*Q
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/** 46K&$6eN
* the basic page utils not including exception sP?$G8-^
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handler )v52y8G-p
* @param everyPage 2\nN4WL
5.
* @param currentPage )jlP
cO-
* @param totalRecords x9)aBB
* @return page O b8B
*/ BU9J_rCIv
publicstatic Page createPage(int everyPage, int -!|WZ
:GQIlA8cF$
currentPage, int totalRecords){ .5Knb c
everyPage = getEveryPage(everyPage); )W`SC mr]
currentPage = getCurrentPage(currentPage); ',JrY)
int beginIndex = getBeginIndex(everyPage, HUJ|-)"dw
UK6xkra?#
currentPage); { eEC:[
int totalPage = getTotalPage(everyPage, 8wII{FHX
+:> J Z$
totalRecords); +%Lt". o
boolean hasNextPage = hasNextPage(currentPage, `s`C{|wv
/}w#Jk4pD
totalPage); y7JZKtsFA
boolean hasPrePage = hasPrePage(currentPage); ?Ml%$z@b?
h@~:(:zU$
returnnew Page(hasPrePage, hasNextPage, Il{^
j6
everyPage, totalPage, [6; N3?+
currentPage, !8Z2X!$m{<
}3f
BY@
beginIndex); hhpv\1h#
} G [3k
6x_T@
privatestaticint getEveryPage(int everyPage){ IX<r5!
return everyPage == 0 ? 10 : everyPage; ~^I\crx,U%
} jow7t\wk
OGJ=VQA
privatestaticint getCurrentPage(int currentPage){ Y5ogi)
return currentPage == 0 ? 1 : currentPage; iW|s|1mh3
} ge0's+E+1
K8
b+
privatestaticint getBeginIndex(int everyPage, int OE'K5oIM
}xDB ~k
currentPage){ ~{kM5:-iw
return(currentPage - 1) * everyPage; /
l".}S
} a-]hW=[
K1T1@ j
privatestaticint getTotalPage(int everyPage, int e(yQKwVD
.Gizz</P~
totalRecords){ 5M%,N-P^
int totalPage = 0; {r={#mO;p
E@w[
if(totalRecords % everyPage == 0) 'h-3V8m^e
totalPage = totalRecords / everyPage; J=UZ){c>:.
else [kbC'Eh*
totalPage = totalRecords / everyPage + 1 ; -IBO5;2_
x*.Ye5Jb
return totalPage; Yd'H+r5b
} 0Injyc*bMF
\\jIl3Z
privatestaticboolean hasPrePage(int currentPage){ ;rd6ko
return currentPage == 1 ? false : true; \bhOPK>w
} 9~@<-6jE3b
J &!B|TS
privatestaticboolean hasNextPage(int currentPage, N-[n\}'
"JkZJ#
int totalPage){ ZCm1+Y$
return currentPage == totalPage || totalPage == 31~hlp;
wms1IV%;
0 ? false : true; 2~f6~\4GL+
} NQ?x8h3
/ZHO>LNN|
||uZ bP@
} cV-i*L4X
P7z:3o.
~32Pjk~
6wPeb~{
FbveI4
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。 /H')~!Yz
2Ok?@ZdjA{
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 mc?';dEG
#c-b}.R
做法如下: MDk*j,5V
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 +%P t_
Vo%Yf9C
的信息,和一个结果集List: *|mz_cKu
java代码: |U#DUqw
wG+=}1X
o]A XT8
/*Created on 2005-6-13*/ ;Xqn-R
package com.adt.bo; d7* CwY9"
B={/nC}G~
import java.util.List; kl"
]Nw'C
-Q#o)o
import org.flyware.util.page.Page; HOfF"QAR$
qNpu}\L
/** Vt'L1Wr0v
* @author Joa jZRh KT
*/ KxY$PgcC
publicclass Result { e#.\^
E#8_hT]5
private Page page; ~;[&K%n
R2l[Q){!
private List content; rJDnuR
[[w2p
/** eK'wVg#
* The default constructor (^LS']ybc
*/ 0Q'v HZ"
public Result(){ &
1[y"S
super(); ]u+MTW;
} x=.tiM {#
{7qA &c=
/** F"'n4|q4n
* The constructor using fields e&0NK8+
* `m%:rE,
* @param page bp#fyG"
* @param content #4><r.v3
*/ Nsn~@.UuSW
public Result(Page page, List content){ \^&
this.page = page; ;UrK{>B
this.content = content; ;|<(9u`
} ~Q?!W0ZBE
Lj8)'[K"
/** n+HsQ]z.
* @return Returns the content. 3y ryeS
*/ .5.8;/
/
publicList getContent(){ [SkKz>rC
return content; qgx?"$ Z
} :6Pnie
=NZ[${7mq
/** D<t~e$ H
* @return Returns the page. SauH>
*/ dv, C6t2
public Page getPage(){ {^J!<k,R\;
return page; ]dG\j^e|
} T1W:>~T5#
b#/i.!:a
/** U]1(&MgV
* @param content ^/dS>_gtHv
* The content to set. \tx%WC
*/ 0I5&a
public void setContent(List content){ v0#*X5C1'
this.content = content; B_k2u
} DK6?E\<
b}@(m$W
/** #f*g]p{
* @param page >&WhQhZ3kg
* The page to set. ,."b3wR[w
*/ F\:(*1C
publicvoid setPage(Page page){ ,3HcCuT
this.page = page; R{?vQsLk
} jJBnDxsA
} L\e>B>u
y bQP E/9
+}aC-&
/syVGmS'M
FRZs[\I|iT
2. 编写业务逻辑接口,并实现它(UserManager, {U"^UuU]
yfEb
UserManagerImpl) 3F+Jdr'
java代码: BAV>o|-K
C!&y
.VM3D0aV
/*Created on 2005-7-15*/ ghAi{@s$)
package com.adt.service; Hx2En:^Gf
I%"'*7U
import net.sf.hibernate.HibernateException; 8uch i
_<zfQZai
import org.flyware.util.page.Page; L9FHgl?
hO#t:WxFI
import com.adt.bo.Result; he$XLTmr:
X}cZxlqc
/** hat>kXm2K
* @author Joa `uo,__y
*/ ;AIc?Cg
publicinterface UserManager { y&oNv
xG-
tmJgm5v
public Result listUser(Page page)throws c|AtBgvf
WKl+{e
HibernateException; TWd;EnNM
"e6|"w@8
} iiG f'@/
8K{[2O7i)
1A<,TFg
q; jiw#_
&aG*k*
java代码: BqH]-'1G
c</1
qAY%nA>jO
/*Created on 2005-7-15*/ gSt`%
package com.adt.service.impl; uD9|.P}
*7$P]
import java.util.List; F|+W.9
xW_yLbE
import net.sf.hibernate.HibernateException; <rIz Z'D
/6+NU^
import org.flyware.util.page.Page; @|\R}k%(
import org.flyware.util.page.PageUtil; Uxu\u0*
E9}{1A
import com.adt.bo.Result; 8VQ 24r
import com.adt.dao.UserDAO; x\\~SGd
import com.adt.exception.ObjectNotFoundException; ycAKK?O*
import com.adt.service.UserManager; a9U_ug58
)92r{%N
/** ]zfG~^.
* @author Joa Vj?DA5W`'
*/ +&|S'7&{
publicclass UserManagerImpl implements UserManager { xV\5<7qk5g
57,dw-|xi
private UserDAO userDAO; a%vrt)Gx
nFRsc'VT
/** Anm=*;*M`
* @param userDAO The userDAO to set. %|"g/2sF[G
*/ k\`S
lb1
publicvoid setUserDAO(UserDAO userDAO){ !CUoHTmB
this.userDAO = userDAO; TsQU6NNE
} a
W%5~3
iK()&TNz
/* (non-Javadoc) &M/>tEZ)
* @see com.adt.service.UserManager#listUser I+(/TP
M*eJ
JY
(org.flyware.util.page.Page) eH%RNtP`
*/ OJAIaC\
public Result listUser(Page page)throws EZDy+6b
8,"yNq
HibernateException, ObjectNotFoundException { x_#-tB
int totalRecords = userDAO.getUserCount(); LiQgR
6j
if(totalRecords == 0) U/l?>lOD\
throw new ObjectNotFoundException ;gg\;i}^
13hE}g;.
("userNotExist"); K(}AX+rIg
page = PageUtil.createPage(page, totalRecords); MrRaU x6z
List users = userDAO.getUserByPage(page); 1.<q3q
returnnew Result(page, users); 9W ^xlid6
} @`36ku
4qi[r)G
} [K/m
tWeFEVg
>slm$~rv
5Por "&%
]b/S6oc6
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 m!tx(XsXU
Z3TS,a1I4
询,接下来编写UserDAO的代码: !p/%lU65
3. UserDAO 和 UserDAOImpl: ``VW;l{
java代码: RoGwK*j0+
W,^W^:m-x
q@hzo>[
/*Created on 2005-7-15*/ Gq<X4C#|
package com.adt.dao; D]G)j
yifY%!@Xu
import java.util.List; :#~U<C@o
KJ2Pb"s
import org.flyware.util.page.Page; WI> P-D
7CXW#H
import net.sf.hibernate.HibernateException; C'yppl%
nrm+z"7
/** q#w8wH"
* @author Joa C)'q
QvA
*/ `
|IUGz
publicinterface UserDAO extends BaseDAO { r}#\BbCv;7
/H7&AiA