Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 89\DS!\x9
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 N'~l,{
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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 \JbOT%1
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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 nj6|WJ
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分页支持类: Qz`v0"'w
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java代码: -^$`5Rk
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package com.javaeye.common.util; ]?lUe5F
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import java.util.List; _:~I(c6
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publicclass PaginationSupport { E~`l/ W
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publicfinalstaticint PAGESIZE = 30; q}cm"lO$
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privateint pageSize = PAGESIZE; [^0 S#,L
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privateList items; T_Cj=>L
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privateint totalCount; >b2wFo/em
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privateint[] indexes = newint[0]; q#\4/Dt
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privateint startIndex = 0; uUJH^pW
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public PaginationSupport(List items, int /Jf}~}JP
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totalCount){ f f5 e]^,
setPageSize(PAGESIZE); CkR
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setTotalCount(totalCount); Y+ !z]S/x
setItems(items); i)=
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setStartIndex(0); JVR,Py:%G
} HcCT=x7:
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public PaginationSupport(List items, int Dbw{E:pq
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totalCount, int startIndex){ hw2Sb,bY
setPageSize(PAGESIZE); Zmz $
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setTotalCount(totalCount); 7UsU03
setItems(items); #j4RX:T*[
setStartIndex(startIndex); nd~O*-uYg
} S#*aB2ZS
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public PaginationSupport(List items, int w\y)
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totalCount, int pageSize, int startIndex){ b=XXp`h~a
setPageSize(pageSize); r<5i
setTotalCount(totalCount); Y|cj&<o
setItems(items); gN.n_!
setStartIndex(startIndex); 47!k!cHa
} uU/'oZ?
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publicList getItems(){ %r]V:d+
return items; J*4T|#0
} pvhN.z
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publicvoid setItems(List items){ Xx1e SX
this.items = items; t&Jrchk
} GTke<R
#=,c8"O
publicint getPageSize(){ 5Kl;(0B9
return pageSize; sB wzb
} .4[M7)
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publicvoid setPageSize(int pageSize){ [F+*e=wjN>
this.pageSize = pageSize; ]JHInt
} }p `A>
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publicint getTotalCount(){ Q!{,^Qb
return totalCount; v(;n|=O
} |:pBk:
5DL(#9F8b9
publicvoid setTotalCount(int totalCount){ .* &F
if(totalCount > 0){ &M7AM"9
this.totalCount = totalCount; +LF`ZXe8l
int count = totalCount / LoW}!,|
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pageSize; e \.
if(totalCount % pageSize > 0) <xUX&J=;
count++; dy4~~~^A
indexes = newint[count]; auAwZi/
for(int i = 0; i < count; i++){ H18pVh
indexes = pageSize * q
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i; jD?*sd
} dH)\zCt
}else{ eC`G0.op
this.totalCount = 0; k,61Va
} 6*:U1{Gl)
} Pr3>}4M
> ,x``-
publicint[] getIndexes(){ lJt?0;gn
return indexes; WmuYHE U
} Bi7&yS5V
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publicvoid setIndexes(int[] indexes){ (Q"~bP{F
this.indexes = indexes; EzU3'x
} vf-8DB
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publicint getStartIndex(){ fvRqt)Ks
return startIndex; ]v l?J
} a1z*Z/!5
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publicvoid setStartIndex(int startIndex){ ZQAiuea
if(totalCount <= 0) yT[)V[}
this.startIndex = 0; ,6aF~p;wI|
elseif(startIndex >= totalCount) [y"Yi PK
this.startIndex = indexes 0E#?H0<OeG
cUTG!
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[indexes.length - 1]; "
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elseif(startIndex < 0) B#4'3Y-3
this.startIndex = 0; Y+Cv9U0
else{ nnCz!:9p
this.startIndex = indexes '^(qlCI
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[startIndex / pageSize]; PV-B<Y
} =g?k`vp
} 3*N0oc^m
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publicint getNextIndex(){ W8M(@*
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int nextIndex = getStartIndex() + i4mP*RwC
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pageSize; ] -%B4lT
if(nextIndex >= totalCount) ?@ 7Reh\
return getStartIndex(); DJ`xCs!R
else cG{
return nextIndex; tNljv >vI
} aVp-Ps|r
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publicint getPreviousIndex(){ m}'!W`<
int previousIndex = getStartIndex() - rW+}3] !D/
+ aWcK6
pageSize; @4$la'XSx
if(previousIndex < 0) LeYI<a@n@$
return0; gdS@NUM
else ($t;Xab
return previousIndex; _gQ_ixu
} eg"A?S
[X ]XH
} KxDfPd+j[
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抽象业务类 gSkY c{b
java代码: wI?AZd;`'
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/** K+`deH_d
* Created on 2005-7-12 &}d5'IRT
*/ f<>CSjQ4c
package com.javaeye.common.business; I2z6iT4nB
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import java.io.Serializable; oG
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import java.util.List; WQMoAPfqL
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import org.hibernate.Criteria; +@~e9ZG%a
import org.hibernate.HibernateException; <t dsUh:?&
import org.hibernate.Session; @#yl_r%
import org.hibernate.criterion.DetachedCriteria; ;WG%)^e
import org.hibernate.criterion.Projections; Rg3g:TV9c
import Fi#
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org.springframework.orm.hibernate3.HibernateCallback; iyr<qtwK
import U "v=XK)!
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org.springframework.orm.hibernate3.support.HibernateDaoS omI"xx
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upport; "8E=*2fcw
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import com.javaeye.common.util.PaginationSupport; ,_@) IN
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public abstract class AbstractManager extends {Rn*)D9
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HibernateDaoSupport { l@`n4U.Gwl
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privateboolean cacheQueries = false; g\ H~Y@'{
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privateString queryCacheRegion; Yn>FSq^Wp-
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publicvoid setCacheQueries(boolean y:k7eE"
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cacheQueries){ J)sOne
this.cacheQueries = cacheQueries; ~I]aUN
} 6t gq.XL^n
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publicvoid setQueryCacheRegion(String d"S\j@
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queryCacheRegion){
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this.queryCacheRegion = $|VdGRZ1
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queryCacheRegion; 8v6AfTo%
} oo1h"[
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publicvoid save(finalObject entity){ +9M";'\c
getHibernateTemplate().save(entity); 10tTV3`IM
} [_*?~
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publicvoid persist(finalObject entity){ f n8|@)J
getHibernateTemplate().save(entity); Q)5V3Q]@^
} TXqtE("BDl
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publicvoid update(finalObject entity){ XE#$|Z
getHibernateTemplate().update(entity); H-eHX3c7
} )U{\c2b
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publicvoid delete(finalObject entity){ eL
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getHibernateTemplate().delete(entity); $ )6x3&]P
} 7_J0[C!G
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publicObject load(finalClass entity, mNJCV8 <
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finalSerializable id){ 0JW
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return getHibernateTemplate().load }4?z<. V
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(entity, id); hb1eEn
} n^<J@uC
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publicObject get(finalClass entity, :g{ybTSEe
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finalSerializable id){ m14'u GC
return getHibernateTemplate().get [{zfI`6
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(entity, id); bQdu= s[
} Rpj{!Ia
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publicList findAll(finalClass entity){ ;,xM*
return getHibernateTemplate().find("from bd2QQ1[1vh
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" + entity.getName()); 2rHQ7
} <KX+j,4
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publicList findByNamedQuery(finalString o* e'D7
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namedQuery){ D#[<N
return getHibernateTemplate lkJe7 +s
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().findByNamedQuery(namedQuery); 4h
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} BadnL<cj]
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publicList findByNamedQuery(finalString query, RL*b47,
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finalObject parameter){ Kd*=-
return getHibernateTemplate lBudC
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().findByNamedQuery(query, parameter); YUTI)&y
} +K,T^<F;
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publicList findByNamedQuery(finalString query, q``/7
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finalObject[] parameters){ c GyBml1
return getHibernateTemplate Lz!H@)-mr
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().findByNamedQuery(query, parameters); EXR6Vb,
} u(8dsgR
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publicList find(finalString query){ UK)wV
return getHibernateTemplate().find x+v&3YF
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(query); 3E}j*lo
} U|8?$/*\
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publicList find(finalString query, finalObject 7Dw.9EQ
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parameter){ z'\BZ5riX<
return getHibernateTemplate().find j|{
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(query, parameter); mZ.gS1Dq
} $"va8,
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public PaginationSupport findPageByCriteria uUe#+[bD
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(final DetachedCriteria detachedCriteria){ _|#P~Ft
return findPageByCriteria m= %KaRI
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ]`|;ZQiD
} bD?gwhAKA
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public PaginationSupport findPageByCriteria {U4{v=,!I
@~FJlG(n
(final DetachedCriteria detachedCriteria, finalint R7c42L\QA
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startIndex){ e}(8BF
return findPageByCriteria ,l.+$G
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(detachedCriteria, PaginationSupport.PAGESIZE, ! 6R|
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startIndex); /JIVp_-p
} Nw%^Gs<~
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public PaginationSupport findPageByCriteria tg<bVA)E'J
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(final DetachedCriteria detachedCriteria, finalint l-5O5|C
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pageSize, cfy9wD
finalint startIndex){ ]hRs -x
return(PaginationSupport) (%G>TV
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getHibernateTemplate().execute(new HibernateCallback(){ B_C."{G
publicObject doInHibernate 0^6}s1d_
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(Session session)throws HibernateException { bAUYJPRpy
Criteria criteria = ,^jQBD4={
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detachedCriteria.getExecutableCriteria(session); E!`/XB/nA
int totalCount = -VP_Aw$
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((Integer) criteria.setProjection(Projections.rowCount fc4jbPp:M
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()).uniqueResult()).intValue(); 3h6,x0AG
criteria.setProjection L!fIAd`
s !II}'Je
(null); M&e=LV
List items = 21] K7
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criteria.setFirstResult(startIndex).setMaxResults DmZ_tuVI
lq?N>~PG
(pageSize).list(); J ayax]u7J
PaginationSupport ps = :u2tu60&MJ
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new PaginationSupport(items, totalCount, pageSize, ;KG}Yr72
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startIndex); YB4|J44Y
return ps; )iZhE"?z
} zLPCWP.u
}, true); c~d*SDca
} y,c\'}*H
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public List findAllByCriteria(final 24fN3
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DetachedCriteria detachedCriteria){ mXu";?2
return(List) getHibernateTemplate J3'0^JP*
PGb}Y {
().execute(new HibernateCallback(){ 0:x+;R<P*w
publicObject doInHibernate $U2Jq@G*
@f-rS{
(Session session)throws HibernateException { X.rbJyKe
Criteria criteria = z;>O5a>z
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detachedCriteria.getExecutableCriteria(session); TC
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return criteria.list(); [7[$P.MS{
} ]ed7Q3lq
}, true); [?da BXS
} :ra[e(l9
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public int getCountByCriteria(final [Uj,, y.wB
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DetachedCriteria detachedCriteria){ N8!e(YK_
Integer count = (Integer) r)<n)eXeD
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getHibernateTemplate().execute(new HibernateCallback(){ Q?'Ax"$D
publicObject doInHibernate bf[l4$3k
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(Session session)throws HibernateException { rWBgYh
Criteria criteria = $<f+CtD4
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detachedCriteria.getExecutableCriteria(session); Z
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return Ge24Lp;Y6
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criteria.setProjection(Projections.rowCount C%P.`Nx A
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()).uniqueResult(); MF$NcU
} P[e#j
}, true); 5=!aq\
5
return count.intValue(); `$/M\aM%
} x
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} U*T :p>&
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用户在web层构造查询条件detachedCriteria,和可选的 8)J,jh9q
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 Z3iX^
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PaginationSupport的实例ps。 ~>}7+p
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ps.getItems()得到已分页好的结果集 <a2Kc '
ps.getIndexes()得到分页索引的数组 w_q=mKu
ps.getTotalCount()得到总结果数 1$"wN z
ps.getStartIndex()当前分页索引 O[^zQA
ps.getNextIndex()下一页索引 MO79FNH2\
ps.getPreviousIndex()上一页索引 %5<t3H"
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 E+eC #!&w
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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 J-Fqw-<aFJ
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一下代码重构了。 Oi n:5K)4-
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我把原本我的做法也提供出来供大家讨论吧: uC1v^!D
et}s yPH
首先,为了实现分页查询,我封装了一个Page类: %W$?*Tm
java代码: ?^:
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/*Created on 2005-4-14*/ DFqVZ
package org.flyware.util.page; nZUBblRJ)
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/** wW^3/
* @author Joa C#.d
sl
* B4 # gT
*/ Yc
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publicclass Page { 6j~'>w(F
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/** imply if the page has previous page */ 7ZgFCK,8m,
privateboolean hasPrePage; z^9df(
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/** imply if the page has next page */ p"J\+R
privateboolean hasNextPage; 4_?*@L1
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/** the number of every page */ )TgjaR9G
privateint everyPage; ZlYb8+rW
iI%"]- 0@1
/** the total page number */ wB0ONH[
privateint totalPage; ed7Hz#Qc
qL68/7:A
/** the number of current page */ tPho4,x$
privateint currentPage; 9Dy/-%Ut9
imf_@_
/** the begin index of the records by the current XAc#ywophi
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query */ [a1}r=6~
privateint beginIndex; YPsuG -is
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/** The default constructor */ GvT'v0&+
public Page(){ w.H\j9E
l
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} $+a2CZs!
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/** construct the page by everyPage HzF]hm,
* @param everyPage EK}f-Xei
* */ DvvjIYB~
public Page(int everyPage){ u-E*_%y
this.everyPage = everyPage; KcX] g*wy
} @~<M_63
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/** The whole constructor */ vZpt}u
public Page(boolean hasPrePage, boolean hasNextPage, W%RjjLJ@
{ sL(PS.z
? k*s!YCZ
int everyPage, int totalPage, `ynD-_fTN
int currentPage, int beginIndex){ Y:XxTa*
this.hasPrePage = hasPrePage; `l95I7
this.hasNextPage = hasNextPage; A?*_14&
this.everyPage = everyPage; .pQ4#AJ
this.totalPage = totalPage; N!F ;!
this.currentPage = currentPage; -kd_gbnr3
this.beginIndex = beginIndex; ~;0J4hR
} pV^hZ.
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/** }$|uIS
* @return !jxz2Q
* Returns the beginIndex. {!hA^[}|
*/ Jm8#M z
publicint getBeginIndex(){ #b4Pn`[
return beginIndex; P:yMj&)
} u;*Wc9>sU
&Rx-zp&dJ
/** ISuye2tExq
* @param beginIndex +9mnxU>
* The beginIndex to set. 64OgE!
*/ Vee`q.
publicvoid setBeginIndex(int beginIndex){
D=nuK25
this.beginIndex = beginIndex; 'WG%O7s.
} 4X2/n
~Xg@,?Zr
/** 2*K _RMr~
* @return 7.PG*q
* Returns the currentPage. wZm=h8d
*/ )_nc;&%w
publicint getCurrentPage(){ n1xN:A
return currentPage; ?qt>;o|Ue
} 8j}CP
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/** 5? `*i"
* @param currentPage W=Ru?sG=
* The currentPage to set. Q1Sf7)
*/ X,<n|zp
publicvoid setCurrentPage(int currentPage){ ^ cn)eA
this.currentPage = currentPage; 8*^Q#;^~99
} /CAi%UH,F
#eT{?_wM
/** %K_[Bx{B
* @return 8ctUK|
* Returns the everyPage. Yl+r>+^
*/ W|@/<K$V
publicint getEveryPage(){ {Ah\-{]
return everyPage; r~uWr'}a}
} Y.qlY3iBp
3cNF^?\=
/** }Zwse%;
* @param everyPage HUtuU X
* The everyPage to set. >g@;`l.Z#
*/ 0k5;Qf6A
publicvoid setEveryPage(int everyPage){ {<a(1#{
this.everyPage = everyPage; !' No5
} vb-L "S?kC
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/** >uuP@j
* @return 37 wm[Z
* Returns the hasNextPage. Z;aQ/n[`
*/ ;Bo{.916
publicboolean getHasNextPage(){ `n]y"rj'
return hasNextPage; tdn[]|=
} *ws!8-)fH
;N4b~k)
/** [{ak&{R,9{
* @param hasNextPage Z_Ox '
* The hasNextPage to set. nl|}_~4U
*/ @O<kjR<b
publicvoid setHasNextPage(boolean hasNextPage){ xr)Rx{)3h
this.hasNextPage = hasNextPage; t,;1?W#
} vIrLG1EK
N?H;fK4v
/** EnJAHgRV;e
* @return jZcjiOX
* Returns the hasPrePage. m-lUgx7
*/ Cyxt EzPp
publicboolean getHasPrePage(){ `5;O|qRq
return hasPrePage; #e0tT+
} !6ZkLE[XJ<
l|`%FB^ k
/** UB]}j^
* @param hasPrePage &_
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* The hasPrePage to set. lM C4j
*/ u2^oXl
publicvoid setHasPrePage(boolean hasPrePage){ `wI<LTzXS
this.hasPrePage = hasPrePage; +d6/*}ht
} !ec\8Tj
,qak_bP
/** &E$jAqc
* @return Returns the totalPage. d{@X-4k:
* `!HGM>
*/ LMWcF'l
publicint getTotalPage(){ 9}Tf9>qP>M
return totalPage; ,ijgq EN
} W$@q
~/E
*usfJ-
/** P@:#NU[
* @param totalPage +I#5?
* The totalPage to set. KP7bU9odJ
*/ |n3PznV
publicvoid setTotalPage(int totalPage){ Re('7m h~
this.totalPage = totalPage; Xd>4n7nb$`
} lNQ t
n*%<!\gJ
}
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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 L@w|2
AZxx%6
个PageUtil,负责对Page对象进行构造: A"k6n\!n;
java代码: Aj.TX%}`h
nI%0u<=d
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/*Created on 2005-4-14*/ kssS,Ogf\_
package org.flyware.util.page; zv!%u=49
:k075Zr/#D
import org.apache.commons.logging.Log; "-kb=fY
import org.apache.commons.logging.LogFactory; Z$Ynar
Y4}!9x
/** D{h1"q
* @author Joa dC_L~ }=
* 'Zf_/y
*/ e|+U7=CK
publicclass PageUtil { ;Aiuy{<
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privatestaticfinal Log logger = LogFactory.getLog 0]{h,W3]@[
@"-<m|lM
(PageUtil.class); %xf6U>T
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/** ~" B0P>7
* Use the origin page to create a new page qr$=oCqa
* @param page Yva^JB
* @param totalRecords 3'O+
* @return 5[esW
*/ 3k5OYUk
publicstatic Page createPage(Page page, int oDTt+b
?UoA'~=
totalRecords){ 1?`,h6d*=
return createPage(page.getEveryPage(), q*TH),)J
\y{Bnp5h
page.getCurrentPage(), totalRecords); 9M:wUYHT
} HQK%Y2S
gAC}
/** gzvEy^X
* the basic page utils not including exception \i}n1Qd
P49lE
handler K_oBSa`
* @param everyPage bS<lB!
* @param currentPage \f1r/e(G|
* @param totalRecords #tKc!]m
* @return page 0K`3BuBs
*/ @3c5"
publicstatic Page createPage(int everyPage, int
]nhLv!Co
"wmQ,=
currentPage, int totalRecords){ 41mg:xW(J
everyPage = getEveryPage(everyPage); b[?6/#N
currentPage = getCurrentPage(currentPage); /d9I2~}B
int beginIndex = getBeginIndex(everyPage, kWc%u-_
#QQ\xj
currentPage); QQ!%lbMK]
int totalPage = getTotalPage(everyPage, hAHl+q)w?
bKYLBu:
totalRecords); [Oe$E5qv)]
boolean hasNextPage = hasNextPage(currentPage, FEw51a+V
5Jd&3pO
totalPage);
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boolean hasPrePage = hasPrePage(currentPage); !]&a/$U
aJ8 8U69
returnnew Page(hasPrePage, hasNextPage, muo(bR8
everyPage, totalPage, bdk"7N
currentPage, vUR{!`14
^q_0(Vf
beginIndex); 5Az=)q4Q
} <33[qt~
^E8&!s
privatestaticint getEveryPage(int everyPage){ )}hp[*C
return everyPage == 0 ? 10 : everyPage; 49^;T;'v
} nV,qC.z
` QXO+'j4
privatestaticint getCurrentPage(int currentPage){ t8\F7F P
return currentPage == 0 ? 1 : currentPage; )\l}i%L:
} gpVZZ:~
Yvs)H'n=
privatestaticint getBeginIndex(int everyPage, int *oL?R2#7
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currentPage){ ZOK2BCoW
return(currentPage - 1) * everyPage; f%` =>l
} b/5?)!I
thDQ44<#)
privatestaticint getTotalPage(int everyPage, int s[NkPh9&
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totalRecords){ 2aX|E4F
int totalPage = 0; D' ZR>@w@
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if(totalRecords % everyPage == 0) Bab`wfUve
totalPage = totalRecords / everyPage; Mg W0
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else (BEGt'7
totalPage = totalRecords / everyPage + 1 ; O&V}T#8n
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return totalPage; Dz:A.x@$*
} MzL^u8
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privatestaticboolean hasPrePage(int currentPage){ f)l:^/WP+
return currentPage == 1 ? false : true; w&hgJ
} msM
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privatestaticboolean hasNextPage(int currentPage, d
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int totalPage){ gPh;
return currentPage == totalPage || totalPage == "}!|V)K
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0 ? false : true; >N62t9Ll[
} pYa8iQ`6U;
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} Fm_^7|
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上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 #3>o^cN~8k
KV9'ew+M
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 Wf/r@/q
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做法如下: KiAWr-~gJ
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 kfr' P u
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的信息,和一个结果集List: H?*EQK`7?0
java代码: ayfR{RYi
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/*Created on 2005-6-13*/ _v bCC7Bf8
package com.adt.bo; Y<-h#_
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import java.util.List; C]414Ibi
%V71W3>6WS
import org.flyware.util.page.Page; !TvNT}4 Z
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/** L[lX?g?Ob
* @author Joa g"ha1<y<
*/ (RVe,0y
publicclass Result { o}$uP5M8q
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private Page page; N;4bEcWjp
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private List content; 5xC4lT/U
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/** J9eOBom8e<
* The default constructor iGB1f*K%x
*/ *;t\!XDgp
public Result(){ 0`c|ZzY
super(); VK*Dm:G0
} Su?e\7aj
k#F |
/** s|F}Abx,^
* The constructor using fields /Cy4]1dw
* mSLA4[4{
* @param page B|pO2de
* @param content 5;'(^z-bL
*/ EQI9J#;+
public Result(Page page, List content){ ~hD!{([
this.page = page; n2}(Pt.
this.content = content; >*s_)IH2
} EP,j+^RVf
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/** kvcDa+#
* @return Returns the content. Em)U`"j/9
*/ S&/,+x'c|
publicList getContent(){ _PT5
return content; ?M!Mb-C[
} 94^)Ar~O
6&|hpp#[
/** Y`F) UwKK
* @return Returns the page. $B%wK`J
*/ }Q$}LR@
public Page getPage(){ q9Zp8&<EqH
return page; T_R2BBT
v
} F!7dGa$
'8%jA$o\g
/** ;)~}/nR<a
* @param content =LXjq~p
* The content to set. YP
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*/ "5<:Dj/W
public void setContent(List content){ 8;6j
this.content = content; ')N[)&&Q{
} 1WjNF i
@k=UB&?I
/** 0JFS%Yjw[
* @param page "s-3226kj
* The page to set. y0vJ@ %`
*/ H9;0$Y(e-
publicvoid setPage(Page page){ ;~D$rT
this.page = page; yFoPCA86y
} $%BI8_
} <W]
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2. 编写业务逻辑接口,并实现它(UserManager, /!Ay12lKE}
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UserManagerImpl) m)7Ql!l
java代码: vB74r]'F
r>: ~!o*
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/*Created on 2005-7-15*/ =6Fpixq>
package com.adt.service; )ifjK6*
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import net.sf.hibernate.HibernateException; E1r-$gf_
(}g4}A@x
import org.flyware.util.page.Page; GY>G}bfh
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import com.adt.bo.Result; =yF]#>Ah
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/** :)Pj()Os|
* @author Joa 3daI_Nx>
*/ H*j!_>W
publicinterface UserManager { LZ34x: ,C
kmUL^vF
public Result listUser(Page page)throws M>E~eb/
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HibernateException; jme`Tyd
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} 2HUw^ *3
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#M%K82"
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java代码: bwM?DY
:8K}e]!c1
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/*Created on 2005-7-15*/ ~NZL~p
package com.adt.service.impl; ;j.-6#n
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import java.util.List; [~PR\qm
Ur]/kij
import net.sf.hibernate.HibernateException; o%bf7)~s
|1GOm=GNK
import org.flyware.util.page.Page; 2X<%BFsE
import org.flyware.util.page.PageUtil; %x.du9
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import com.adt.bo.Result; TjDtNE
import com.adt.dao.UserDAO; 'hE'h?-7
import com.adt.exception.ObjectNotFoundException; qA;Gl"HF
import com.adt.service.UserManager; &wAVO_s
Kt](|
/** m/Erw"Z
* @author Joa hq&|
*/ @DIEENiM
publicclass UserManagerImpl implements UserManager { #dKy{Q3he
Vm8@LA
private UserDAO userDAO; )X;051Q
j+fib} 8}
/** J5(0J7C
* @param userDAO The userDAO to set. iciKjXJ:
*/ NRny]!
publicvoid setUserDAO(UserDAO userDAO){ 2"HTD|yy
this.userDAO = userDAO; ZNne 8
} /vq$/
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/* (non-Javadoc) P1AC2<H
* @see com.adt.service.UserManager#listUser XUzOt_L5<
p^|6 /b
(org.flyware.util.page.Page) wZZ~!"O&
*/ ]J [d8S5
public Result listUser(Page page)throws S)g:+P
Fgi`g{N
HibernateException, ObjectNotFoundException { }K8e(i6z
int totalRecords = userDAO.getUserCount(); LPBa!fq
if(totalRecords == 0) Ui!l3_O
throw new ObjectNotFoundException 7O'.KoMw
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("userNotExist"); Ml$<x"Q
page = PageUtil.createPage(page, totalRecords); 7nNNc[d*=
List users = userDAO.getUserByPage(page); CIz0Gjtx6m
returnnew Result(page, users); pU9.#O
} 5RvE ),
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} PWZd<
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 -uWV(
,|
Xp_m=QQsm
询,接下来编写UserDAO的代码: {g#4E0.A!
3. UserDAO 和 UserDAOImpl: H0#=oJr$)W
java代码: ]iGeqwT
R|}N"J _
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/*Created on 2005-7-15*/ ^~I@]5Pq
package com.adt.dao; +}N'Xa/Jt
t/Y0e#9,
import java.util.List; Bcarx<P-p
4xEw2F
import org.flyware.util.page.Page; zPND$3&'
[nZIV
import net.sf.hibernate.HibernateException; -&sY