Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Sd\@Q%
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ( gFA? aD<
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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 aw4+1.xy
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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 ^+wzm2i
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分页支持类: [:=[QlvV
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java代码: z0UO<Y?9
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package com.javaeye.common.util; W|Tew-H{h_
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import java.util.List; 2Ee1mbZVw8
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publicclass PaginationSupport { +UsR
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publicfinalstaticint PAGESIZE = 30; w+Z};C
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privateint pageSize = PAGESIZE; e ^qnUjMy
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privateList items; &zd7t6
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privateint totalCount; $"(YE #]|
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privateint[] indexes = newint[0]; S- \lN|
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privateint startIndex = 0; !491
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public PaginationSupport(List items, int V<pqc&f.
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totalCount){ vWovR`
setPageSize(PAGESIZE); Z4-dF;7
setTotalCount(totalCount); DmrfD28j~F
setItems(items); kC5,yj
setStartIndex(0); n6Zx0ad?
} o5@ jMU;
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public PaginationSupport(List items, int A
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totalCount, int startIndex){ 1c"m$)a4
setPageSize(PAGESIZE); ]e`_.>U
setTotalCount(totalCount); QX=;,tr
setItems(items); gWo~o]f
setStartIndex(startIndex); R"o,m
} NXNon*"
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public PaginationSupport(List items, int mlWIq]J
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totalCount, int pageSize, int startIndex){ 7qz-RF#s8
setPageSize(pageSize); .rm7Sd4K
setTotalCount(totalCount); Umt ia~x=&
setItems(items); kAliCD)
setStartIndex(startIndex); ')-(N
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} EM/+1
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publicList getItems(){ t
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return items; \>`$x:
} Av>j+O ;
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publicvoid setItems(List items){ ,b(S=r
this.items = items; vxT"BvN
} DOIWhd5:
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publicint getPageSize(){ RbM~E~$
return pageSize; 26VdRy{[
} 2H+DT-hK
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publicvoid setPageSize(int pageSize){ WGluY>C;
this.pageSize = pageSize; ee^_Dh4
} :*'?Ac
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publicint getTotalCount(){
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return totalCount; 3F} KrG
} 5yiiPK$qr
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publicvoid setTotalCount(int totalCount){ }C"*ACjF
if(totalCount > 0){ gA1in
this.totalCount = totalCount; p-r%MnT
int count = totalCount / 5@+E i25
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pageSize; f$|v0Xs
if(totalCount % pageSize > 0) $2C GRhC
count++; s7i.p]
indexes = newint[count]; cgXF|'yI&l
for(int i = 0; i < count; i++){
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indexes = pageSize * ^p zxwt
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} QU!'W&F6
}else{ I*S`I|{J
this.totalCount = 0; 3ZlGbP#3w
} @dCPa7:>&
} _xgVuJ
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publicint[] getIndexes(){ $,,>R[; w
return indexes; }lTZq|;A
} WriN]/yD
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publicvoid setIndexes(int[] indexes){ 3@`H<tP'6o
this.indexes = indexes; <4e*3WSG
} kok^4VV
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publicint getStartIndex(){ /+t[,
return startIndex; &:I
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} LZC?383'
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publicvoid setStartIndex(int startIndex){ Cm;qDvj+u
if(totalCount <= 0) )USC
this.startIndex = 0; YQ@6innT
elseif(startIndex >= totalCount) L##8+OJ.L
this.startIndex = indexes
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[indexes.length - 1]; &:CjUaP@
elseif(startIndex < 0) k-pEBhOH
this.startIndex = 0; CCh8? sM
else{ Y0B1xL@
this.startIndex = indexes m?VRX.>
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[startIndex / pageSize]; 9N
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}
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} _|
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publicint getNextIndex(){ #H6g&)Z_
int nextIndex = getStartIndex() + j"IM,=
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pageSize; A$%!9Cma
if(nextIndex >= totalCount) CTkN8{2S
return getStartIndex(); )ozcr^
else )ClMw!ZrU
return nextIndex; 2vkB<[tSs
} >6I.%!jU
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publicint getPreviousIndex(){ &u1g7#
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int previousIndex = getStartIndex() - u[i7:V%
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pageSize;
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if(previousIndex < 0) CC>fm1#i\
return0; >U~|R=*
else DqzA U7
return previousIndex; .?0>5-SfY
} q|u8CX
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} TA0D{
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抽象业务类 SE^b0ZV*x
java代码: t+ S~u^
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/** JOdwv4(3V
* Created on 2005-7-12 U$A7EFK'
*/ Q-`{PJ(p
package com.javaeye.common.business; D!RE-w92X
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import java.io.Serializable; $,;S\JmWP
import java.util.List; '>e79f-O)
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import org.hibernate.Criteria; zvGK6qCk
import org.hibernate.HibernateException; TsX+. i'
import org.hibernate.Session; <4Q1 2:
import org.hibernate.criterion.DetachedCriteria; k%l_N)38
import org.hibernate.criterion.Projections; e$Bf[F#;-
import ~y)bYG!G
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org.springframework.orm.hibernate3.HibernateCallback; kPO6gdwq$
import bR'mV-2'
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org.springframework.orm.hibernate3.support.HibernateDaoS 8jjFC9Cbn0
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upport; e?!L}^f6X
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import com.javaeye.common.util.PaginationSupport; 7<3U? ]0
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public abstract class AbstractManager extends ,!I?)hwOC
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HibernateDaoSupport { 9fNu?dE
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privateboolean cacheQueries = false;
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privateString queryCacheRegion; PEW4J{(W
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publicvoid setCacheQueries(boolean `S \zqF<
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cacheQueries){ I7fb}j`/
this.cacheQueries = cacheQueries; *#1y6^
} fVDDYo2\
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publicvoid setQueryCacheRegion(String #v4LoNm
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queryCacheRegion){ )u8*zwq
this.queryCacheRegion = 1yBt/U2
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queryCacheRegion; hIuMHq7h
} oTCzY Y
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publicvoid save(finalObject entity){ Tm)GC_
getHibernateTemplate().save(entity); OJP5k/U$
} <b d1
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publicvoid persist(finalObject entity){ q^a|wTC
getHibernateTemplate().save(entity); D<U
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} b mOqeUgB
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publicvoid update(finalObject entity){ C$<"w,
getHibernateTemplate().update(entity); VEj$^bpp5s
} S]&8St
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publicvoid delete(finalObject entity){ -AjH}A[!
getHibernateTemplate().delete(entity); oW1"%i%
} ~x|aoozL
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publicObject load(finalClass entity, keLR1qf
7]Al*)
finalSerializable id){ e74zR6
return getHibernateTemplate().load B%tIwUE2
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(entity, id); U4>O\sU
} [o2w1R\H+x
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publicObject get(finalClass entity, UJz#QkAio
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finalSerializable id){ 0"EoC
return getHibernateTemplate().get "S5S|dBc
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(entity, id); vS OT*0r
} 01udlW.
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publicList findAll(finalClass entity){ ao#!7F
return getHibernateTemplate().find("from M[, D *
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" + entity.getName()); cjuZBFl
} ^=EjadVQ
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publicList findByNamedQuery(finalString ZJ;LD*
*'D=1{WZ!
namedQuery){ z[fB!O
return getHibernateTemplate lT.zNhz:d9
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().findByNamedQuery(namedQuery); zZ%DtxUoU.
} }A]BpSEP
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publicList findByNamedQuery(finalString query, ^q
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finalObject parameter){ ^[k0k(_
return getHibernateTemplate 3{"byfO#%
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().findByNamedQuery(query, parameter); ?d$"[lKX
} AoBoFZLl3
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publicList findByNamedQuery(finalString query, m0|K#^
;7Y[c}V1^
finalObject[] parameters){ jM~Bu.7 i6
return getHibernateTemplate TyF{tuF
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().findByNamedQuery(query, parameters); 17}$=#SX
} V/PAi.GZ
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publicList find(finalString query){ j{"z4Y4
return getHibernateTemplate().find +$47v$p
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(query); 5IW8=$k~.)
} *8bK')W
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publicList find(finalString query, finalObject 9Bz0MUbrLl
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parameter){ Vtb1[cnna
return getHibernateTemplate().find n`(~OO
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(query, parameter); rK1-Mu
} Z!6UW:&~7
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public PaginationSupport findPageByCriteria )RN<GW'
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(final DetachedCriteria detachedCriteria){ j!\dn!Xwt
return findPageByCriteria ?}}qu'N:N
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); p3c"ZPO~z
} %r%So_^
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public PaginationSupport findPageByCriteria R(k}y,eh.`
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(final DetachedCriteria detachedCriteria, finalint =E(#YCx
Z) Wnow
startIndex){
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return findPageByCriteria mN*?%t
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(detachedCriteria, PaginationSupport.PAGESIZE, tdep|sD
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startIndex); m:uPEpcU
} +dk fcG
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public PaginationSupport findPageByCriteria =su]w2,Iy
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(final DetachedCriteria detachedCriteria, finalint hmpr%(c `
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pageSize, ,:)`+v<
finalint startIndex){ 1!1!PA9u
return(PaginationSupport) ZF6c{~D
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getHibernateTemplate().execute(new HibernateCallback(){ DkDoA;m
publicObject doInHibernate k?*KnfVh!
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(Session session)throws HibernateException { Y-)xTn
Criteria criteria = ${I*nh>=
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detachedCriteria.getExecutableCriteria(session); J0Z7l
int totalCount = 3Bd X
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((Integer) criteria.setProjection(Projections.rowCount ***a2Z/(
uo2'"@[e
()).uniqueResult()).intValue(); ! zL1;d
criteria.setProjection tF7hFL5f
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(null); NBYH;h P
List items = x|i_P|Z
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criteria.setFirstResult(startIndex).setMaxResults :"Y*<=x#2
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(pageSize).list(); \?**2{9&)
PaginationSupport ps = Kcy@$uF{2
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new PaginationSupport(items, totalCount, pageSize, u
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startIndex); X6\ sF"E
return ps; >yB(lKV
} >6<q8{*
}, true); #wY0D_3@1
} _%/}>L>-`8
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public List findAllByCriteria(final zmI] cD@G
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DetachedCriteria detachedCriteria){ ICC%,$C~l
return(List) getHibernateTemplate hI},~af
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().execute(new HibernateCallback(){ :e<7d8E5n{
publicObject doInHibernate ?QZ"JX])
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(Session session)throws HibernateException { _n;;][]S
Criteria criteria = l{Dct\ #s
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detachedCriteria.getExecutableCriteria(session); A\fb<
return criteria.list(); v{aq`uH
} :Dt~e|
}, true); q%Yn;g|_
} up>c$jJ
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public int getCountByCriteria(final :,B7-kBw
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DetachedCriteria detachedCriteria){ *v
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Integer count = (Integer) A A^{B
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getHibernateTemplate().execute(new HibernateCallback(){ zK|i='XSf
publicObject doInHibernate PjKECN
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(Session session)throws HibernateException { ;&V s4
Criteria criteria = >J9oH=S6
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detachedCriteria.getExecutableCriteria(session); vS\Nd1~ ?
return SAYLG
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criteria.setProjection(Projections.rowCount HpZ1xT
N@ \&1I`c$
()).uniqueResult(); EU7|,>a
} V!v:]E
}, true); f| _u7"OX
return count.intValue(); 5"XC$?I<}
} PHOP%hI$
} 0k)rc$eDF+
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用户在web层构造查询条件detachedCriteria,和可选的 ?POUtRN
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 LUB${0BrA
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PaginationSupport的实例ps。 (T`E!A0I\?
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ps.getItems()得到已分页好的结果集 f+8wl!M+6
ps.getIndexes()得到分页索引的数组 o1M$.*
ps.getTotalCount()得到总结果数 n3AaZp[
ps.getStartIndex()当前分页索引 (aOv#Vor]%
ps.getNextIndex()下一页索引 P3$Q&^?
ps.getPreviousIndex()上一页索引 O nQdq^UB
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 UMAgA!s
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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 zR2B-
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一下代码重构了。 $Y69@s %f
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我把原本我的做法也提供出来供大家讨论吧: wF((
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首先,为了实现分页查询,我封装了一个Page类: hzk cP
java代码: D$t k<{)oB
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/*Created on 2005-4-14*/ ZK>WW
package org.flyware.util.page; _/i4MtM
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/** ty8v
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* @author Joa ")d`dj\o
* d_IAs
*/ 8F._9U-EN
publicclass Page { &Z`#cMR{H
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/** imply if the page has previous page */ (1#J%
privateboolean hasPrePage; Q%xC}||1s"
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/** imply if the page has next page */ yu;P +G
privateboolean hasNextPage; C.FI~Z
."9];)2rx
/** the number of every page */ B)0i:"q
privateint everyPage; {{QELfH2
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/** the total page number */ zAiXo__x
privateint totalPage; rx] @A
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/** the number of current page */ V#iPj'*
privateint currentPage; Y'8?.a]'
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/** the begin index of the records by the current ZzSz%z_sE
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query */ 0tXS3+@n=
privateint beginIndex; ' ~8KSF*!p
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/** The default constructor */ +mn,F};
public Page(){ Le\?+h42>
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} "hsb8-
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/** construct the page by everyPage ~vyf4TF<#
* @param everyPage [5SD_dN
* */ z*a:L} $
public Page(int everyPage){ 2+e}*&iQpp
this.everyPage = everyPage; nCdR EXw
} V=o
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/** The whole constructor */ ]?!mS[X
public Page(boolean hasPrePage, boolean hasNextPage, a ?)NC
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int everyPage, int totalPage, E&[{4Ml
int currentPage, int beginIndex){ 5:KQg
this.hasPrePage = hasPrePage; Zg{KFM%
this.hasNextPage = hasNextPage; ppVHLrUh
this.everyPage = everyPage; ;EP:o%r
this.totalPage = totalPage; w|K'M?N14
this.currentPage = currentPage; &7K?w~
this.beginIndex = beginIndex; cWe"%I
} KV0]m^@x
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/** xD~5UER
* @return DK:o]~n
* Returns the beginIndex. Al}B34.uh
*/ |xdsl,
publicint getBeginIndex(){ k@k&}N0{
return beginIndex; `T5W}p[6
} ]1#e#M]#
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/** Ju1D
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* @param beginIndex @~"h62=]
-
* The beginIndex to set. `xqr{lhL
*/ >JFO@O5
publicvoid setBeginIndex(int beginIndex){
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this.beginIndex = beginIndex; rrik,qyv6
} ] Zy5%gI
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/** {#?N
* @return Ac2n
* Returns the currentPage. {Tq_7,8
*/ V{/?FO?E
publicint getCurrentPage(){ a%/9v"}
return currentPage; s@K4u^$A
} .$+#1-
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/** }HFN3cq;C
* @param currentPage 'h|DO/X~L
* The currentPage to set. >4TaP*_
*/ r\'A
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publicvoid setCurrentPage(int currentPage){ o$jLzE"
this.currentPage = currentPage; uKUiV%p!
} g| I6'K!<
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/** (MxQ+D\
* @return MOQ*]fV:
* Returns the everyPage. d928~y
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*/ \`~Ly-
publicint getEveryPage(){ }v}P
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return everyPage; R;&AijS8
} YNKHN2E8
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/** &^}1O:8e
* @param everyPage ib#KpEk
* The everyPage to set. =Y|VgV
*/ r1 !@hT
publicvoid setEveryPage(int everyPage){ `yrB->|vG
this.everyPage = everyPage; xr4*{v
} 6t[+pL\b
7)`nD<j5
/**
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* @return i&bA2p3+d
* Returns the hasNextPage. S&Zm0Ku
*/ vlmB`T
publicboolean getHasNextPage(){ qouhuH_WtJ
return hasNextPage; %Nlt H/I
} M ?Y;a5{
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/** `u3EU*~W
* @param hasNextPage BC&S> #\
* The hasNextPage to set. N{9v1`B
*/ gc_:%ki
publicvoid setHasNextPage(boolean hasNextPage){ il4^zj82
this.hasNextPage = hasNextPage; #+ 0M2Sa
} LM~[@_j
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/** } gyj0
* @return z+0I#kM"1
* Returns the hasPrePage. 3]}D`Qs6
*/ %?0:vn
publicboolean getHasPrePage(){ @vC4[:"pD}
return hasPrePage; w'Y7IlC
} Ns>-
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/** N)uSG&S:
* @param hasPrePage 6Zm# bFQ
* The hasPrePage to set. I0D(F
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*/ eI$oLl@
publicvoid setHasPrePage(boolean hasPrePage){ _mqL8ho
this.hasPrePage = hasPrePage; )B"jF>9)[
} ]sf7{lVT
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/** ?pW`cFLDHF
* @return Returns the totalPage. GZN ^k+w
* eVjBGJ=2e
*/ <=zQ NBtx
publicint getTotalPage(){ n\Z!ff/
return totalPage; !![DJ
} X9v.1s,
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/** -;s|
* @param totalPage xI #9
* The totalPage to set. j/323Za+
*/ `uv2H$
publicvoid setTotalPage(int totalPage){ W#9BNKL
this.totalPage = totalPage; u_w#gjiC
} 2Q/x@aT,h
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} SE@LYeC}dE
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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 [L3=x;U
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个PageUtil,负责对Page对象进行构造: ? &o2st
java代码: 9&-dTayIz
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/*Created on 2005-4-14*/ |HiE@
package org.flyware.util.page; y`Wty@
>:74%D0UF
import org.apache.commons.logging.Log; [owWiN4`s
import org.apache.commons.logging.LogFactory; Ci@o|Y }tP
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/** ~qiJR`Jj
* @author Joa }*M6x;t
* $t$ShT)
*/ y;35WtDVb
publicclass PageUtil { j+i\bks
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privatestaticfinal Log logger = LogFactory.getLog {%rA1g
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(PageUtil.class); .?8;q A
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/** -o^7r@6
* Use the origin page to create a new page U$O\f18
* @param page m ifxiV
* @param totalRecords \r/rBa\
* @return ? ^0:3$La
*/ #3i3G(mQ
publicstatic Page createPage(Page page, int [;n9:Qxf
+F R0(T
totalRecords){ H*d9l2,KZS
return createPage(page.getEveryPage(), ]AINKUI0
O*hDbM2QQw
page.getCurrentPage(), totalRecords); S]}nm
} %|s; C
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/** EuZ<quwWg
* the basic page utils not including exception @:oXN]+
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handler b)6D_Az7c
* @param everyPage %R}qg6dL
* @param currentPage , Rk9N
* @param totalRecords ax"+0L{
* @return page \ ZgE
*/ LK{*sHi$
publicstatic Page createPage(int everyPage, int sQYkQ81
wg9t)1k{e
currentPage, int totalRecords){ *D'22TO[[!
everyPage = getEveryPage(everyPage); 9&$y}Y
currentPage = getCurrentPage(currentPage);
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int beginIndex = getBeginIndex(everyPage, 7o7)0l9!
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currentPage); ()Y~Q(5ji
int totalPage = getTotalPage(everyPage, z 9vInf@M
3U<cWl@
totalRecords); S ^!n45l
boolean hasNextPage = hasNextPage(currentPage, DBo%fYst
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totalPage); dH;8mb|#'
boolean hasPrePage = hasPrePage(currentPage); ~uj#4>3T
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returnnew Page(hasPrePage, hasNextPage, ]Z>}6!
everyPage, totalPage, ;@mS^ik")$
currentPage, /MIe(,>Uh
QJZK|*
beginIndex); qLO4#CKCL6
} 'F/~o1\.
5VfyU8)7X
privatestaticint getEveryPage(int everyPage){ +KF^Z$I
return everyPage == 0 ? 10 : everyPage; Q7HRzA^-
} Sgeh %f
i[O& )N,c
privatestaticint getCurrentPage(int currentPage){ `fA@hK
return currentPage == 0 ? 1 : currentPage; ^7w+l @
} `{f}3bO7C
zG }@0
privatestaticint getBeginIndex(int everyPage, int ?qmRbDI
"H=6j)Cb
currentPage){ 0CWvYC%e
return(currentPage - 1) * everyPage; 6gL#C&
} `XJG(Oas\
R
privatestaticint getTotalPage(int everyPage, int MR;1
2*p
YDIG,%uv
totalRecords){ pI1-cV,`
int totalPage = 0; ;dkYf24
T]^62(So
if(totalRecords % everyPage == 0) Fe# 1
totalPage = totalRecords / everyPage; 9>=;FY
else 9"N~yKa`"K
totalPage = totalRecords / everyPage + 1 ; B~'vCuE
j%Y#(Q>
return totalPage; =Z{O<xw'
} )\1@V+!E%
'50OgF'
privatestaticboolean hasPrePage(int currentPage){ )Oq|amvC
return currentPage == 1 ? false : true; #oS<E1
} ;(b9#b.
U#0Q)
privatestaticboolean hasNextPage(int currentPage, 46}g7skD
.ODU
int totalPage){ y;4OY
return currentPage == totalPage || totalPage == 4(#'_jS
1NbG>E#Ol
0 ? false : true; R6 y#S&]x
} ^+*N%yr
5 )A1\
*1ilkmL%
} >,v`EIg
eln)BW#
HSw;^E)1
2% MC Yn
im${3 >26
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。
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lz/8
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 =h-U
t0( A4E
做法如下: ZAW^/bo<
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 9#23FK
Yc`o5Q\>
的信息,和一个结果集List: Fh)IgzFj
java代码: 48J@CvU
>>QY'1Eu
T tfo^ksw
/*Created on 2005-6-13*/ eJrQ\>z]V&
package com.adt.bo; oro$wFxJO
[NF'oRRD9s
import java.util.List; ^dI424
kPKB|kP\
import org.flyware.util.page.Page; ! :Y:pu0
*Hg>[@dP0
/** 7dN*lks
* @author Joa PoHg,n]
*/ :>rkG?NfL
publicclass Result { $1SPy|y
q?Cnav`DY
private Page page; gK+4C
@Y?#Sl*
private List content; e-~N"
_H9 MwJ
/** d|jNf</`
* The default constructor #"}JdBn
*/ 2my_ ;!6T[
public Result(){ *~2,/D
super(); DMs,y{v
} b
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N(O9&L*4fm
/** %9
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* The constructor using fields i9rN9Mq?O
* @g|v;B|{
* @param page u/UrAqw
* @param content @Rg/~\ K
*/ 50"pbzW
public Result(Page page, List content){ dSLU>E3g
this.page = page; ;Y)w@bNt@
this.content = content; bAdn &
} ov|d^)'
{5A2&
/** J.3u^~zy
* @return Returns the content. <3L5"77G6
*/ bs+f,j-oBN
publicList getContent(){ pk>^?MO
return content; IWk4&yHUAu
} Lk|hQ
!'Ak&j1:`
/** Plc-4y1
* @return Returns the page. 1&\0:vA^Y
*/ ;[(oaK@+n
public Page getPage(){ y$;/Vm_'
return page; []D&bYpv
} t1]K<>g
md+nj{Ib
/** =-tw5],
L
* @param content zlyS}x@p
* The content to set.
3Nl <p"=
*/ p$O.>
[
public void setContent(List content){ 3N8t`N
this.content = content; zh%#Y_[R
} PoNi"Pv
9q)Kfz
/** N>Xo_-QCY
* @param page \TIT:1
* The page to set. ]{!U@b
*/ eFipIn)b
publicvoid setPage(Page page){ bT</3>+C
this.page = page; qjc8fP2
} Nv$R\' 3
}
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PYQ;``~x
W=lyIb{?^0
mD/9J5:
@efh{
2. 编写业务逻辑接口,并实现它(UserManager, "_P;2N6
0*VWzH
UserManagerImpl) q$p%ZefZ
java代码: ) g0%{dfJ
Y$o<6[7
z__EYh
/*Created on 2005-7-15*/ 4Xgg%@C
package com.adt.service; >1s*
at/h
>/{@C
import net.sf.hibernate.HibernateException; 9K.Vb1&
1Vsz4P"O $
import org.flyware.util.page.Page; A_V]yP
]E7F/O/.
import com.adt.bo.Result; 3^IpE];+:u
Gq+z /Be
/** f W!a|?e$
* @author Joa !]42^?GH
*/ 2iHUZzz\
publicinterface UserManager { !NIhx109q
@X%C>iYa9
public Result listUser(Page page)throws ]Gzm^6v
D!@Ciw
HibernateException; Yf:IKY
5c9^-|-T
} ^"2i
~Uu4=
e%@'5k\SK
0\H\lKcK
EH$1fvE
java代码: bNm#tmSt
,bXe<L)
}bs+-K
/*Created on 2005-7-15*/ YA''2Ii
package com.adt.service.impl; Az9?Ra;U
Gp1?iX?ml
import java.util.List; >c1!p]&V
I*o()
import net.sf.hibernate.HibernateException; z[LNf.)}
5rwu!Y;7*
import org.flyware.util.page.Page; -]L6=
import org.flyware.util.page.PageUtil; v;BV@E0}x
3("_Z%
import com.adt.bo.Result; f6EZ(
v
import com.adt.dao.UserDAO; \"qY "V
import com.adt.exception.ObjectNotFoundException; Vl5`U'^qx
import com.adt.service.UserManager; b v G/|U
t
4PK}>QW
/** bhID#&
* @author Joa .O74V~T
*/ pqk?|BvpK_
publicclass UserManagerImpl implements UserManager { H0:E(}@
gGvz(R:y
private UserDAO userDAO; c*(bO3 b
|^0XYBxQ
/** H]P.
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* @param userDAO The userDAO to set. J
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*/ *,3SGcYdJj
publicvoid setUserDAO(UserDAO userDAO){ D~biKrg?=
this.userDAO = userDAO; [6 pD
} <
nXL
ht7l- AK
/* (non-Javadoc) 00'%EYO
* @see com.adt.service.UserManager#listUser :X0k]p
;QWIsVz
(org.flyware.util.page.Page) V\t.3vT
*/ BD68$y
public Result listUser(Page page)throws @"hb) 8ng
nePfuG]Q
HibernateException, ObjectNotFoundException { 5*E]ETo@R
int totalRecords = userDAO.getUserCount(); O#b6mKPt;t
if(totalRecords == 0) O|\J}rm'
throw new ObjectNotFoundException c$ao:nP)D
dUsYZdQs
("userNotExist"); $()5VMb
page = PageUtil.createPage(page, totalRecords); 9Kpa><
List users = userDAO.getUserByPage(page); M2d$4-<
returnnew Result(page, users); yQU_>_!n
} FO=4:
mN~ci 0
} 3)8QS
34z"Pm
io _1Y]N
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x8wD0D
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 GU4'&#
4P'*umJi
询,接下来编写UserDAO的代码: !5.8]v
3. UserDAO 和 UserDAOImpl: XJ;D=~
java代码: 1s%#$ 7
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jB`,u|FG
/*Created on 2005-7-15*/ `rgn<I"
package com.adt.dao; RzBF~2 >i
?a8^1:
import java.util.List; <d,b '<z
s
LwrUQ)
import org.flyware.util.page.Page; cFaaLUZk
Jzj1w}?H
import net.sf.hibernate.HibernateException; lU@]@_<
Xp >7iX!:
/** u&`XB|~
* @author Joa >CrA;\l
*/ <<@bl@9'
publicinterface UserDAO extends BaseDAO { 5Eg1Q
YVt
1|RANy
publicList getUserByName(String name)throws =5Q]m6-SgV
2-7IJ\
HibernateException; yGWxpzmRS
bW$J~ ynM
publicint getUserCount()throws HibernateException; 6,)[+Bl
Q
7
publicList getUserByPage(Page page)throws (mgS"zPS
|y&*MTfV4L
HibernateException; Z8zmHc"IH
]or>?{4g
} cJN7bA{
XaCX!Lr,
PRr2F-!P
!>v2i"
{wO3<9
java代码: L0*nm.1X
~R_ztD+C(
lV`Q{bd+
/*Created on 2005-7-15*/ H(bs$C4F
package com.adt.dao.impl; F5?m6`g?
'd.EC#
import java.util.List; 5V6G=H
pNOwDJtK
import org.flyware.util.page.Page; ' qWALu
Du`JaJI
import net.sf.hibernate.HibernateException; #z&&M"*a|
import net.sf.hibernate.Query; X*M#FT-
uv=.2U46
import com.adt.dao.UserDAO; }E0,z
.Si,dc\
/** *FC=X) _&W
* @author Joa P\w\N2
*/ eCN })An
public class UserDAOImpl extends BaseDAOHibernateImpl }2<r,
,a gc
implements UserDAO { \n{qsf:
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/* (non-Javadoc) }R1<
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* @see com.adt.dao.UserDAO#getUserByName s>0't
T,]7ICF#
(java.lang.String) "B=
*/ }!;s.[y
publicList getUserByName(String name)throws ?3%`bY+3;
_9JhL:cY
HibernateException { cV 5CaaL
String querySentence = "FROM user in class 6I1,:nLL<
S'A>2>
com.adt.po.User WHERE user.name=:name"; (5R?#vj
Query query = getSession().createQuery +s,Qmmb7)
g6Q !8
(querySentence); 7N-w eX
query.setParameter("name", name); :,Pn3xl
return query.list(); y=`2\L" O
} N$h{Yvbn
&0NFb^8+
/* (non-Javadoc) GqWB{$J;"
* @see com.adt.dao.UserDAO#getUserCount() cc#gEm)3C
*/ w9NHk~LHKF
publicint getUserCount()throws HibernateException { ux_Mrh'
int count = 0; ?**+e%$$
String querySentence = "SELECT count(*) FROM eln&]d;
q8s0AN'@t'
user in class com.adt.po.User"; OJ/,pLYu
Query query = getSession().createQuery Ko;{I?c
0}$Hi
(querySentence); CACTE
count = ((Integer)query.iterate().next Cg&e(
hvA^n@nr
()).intValue(); lz"OC<D}(
return count; RnhL<
Ywu
} ,_yhz0.
kD*2~Z ?;
/* (non-Javadoc) Ys@}3\Mc
* @see com.adt.dao.UserDAO#getUserByPage an|x$e7|?
p8Q,@ql.
(org.flyware.util.page.Page) HR
;)|j{!
*/ aCQ?fq
publicList getUserByPage(Page page)throws >Y
#t`6,!
11<Qxu$rL
HibernateException { PIH*Rw*GKZ
String querySentence = "FROM user in class Z0 o~+Ct$
$4tWI O
com.adt.po.User"; !|O~$2O@
Query query = getSession().createQuery U7oo$gW%|T
"Jt.lL ]5
(querySentence); 4zJtOK?r"
query.setFirstResult(page.getBeginIndex()) f2^r[kPX"
.setMaxResults(page.getEveryPage()); wtc!>
return query.list(); tcLnN:
} 3E>frR\!I
!R1.7}O
} h&Efg