Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 5zB~4 u
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 @_yoX(.E&
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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 `JURQ:l)3^
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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 go'j/4Tp
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。 :dnJY%/q
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分页支持类: VaLs`q&3>
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java代码: ;['a
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package com.javaeye.common.util; |i7a@'0)
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import java.util.List; D4u%6R|F
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publicclass PaginationSupport { h~}.G{"
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publicfinalstaticint PAGESIZE = 30; ^@6q
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privateint pageSize = PAGESIZE; QP(BZJC
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privateList items; nJFg^s1
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privateint totalCount; kOrl\_!z3
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privateint[] indexes = newint[0]; LKF/u` 0dP
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privateint startIndex = 0; zI;0&
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public PaginationSupport(List items, int ~r*P]*51x
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totalCount){ nsuX*C7
setPageSize(PAGESIZE); xge7r3i
setTotalCount(totalCount); #JW+~FU`
setItems(items); 9pSUIl9|j
setStartIndex(0); Ud(`V:d
} ~mp0B9L%
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public PaginationSupport(List items, int H)(jh
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totalCount, int startIndex){ Gc,_v3\
setPageSize(PAGESIZE); K|r Lkl9
setTotalCount(totalCount); L^`}J7r
setItems(items); |oFAGP1
setStartIndex(startIndex); obH;g*
} #f,y&\Xmf
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public PaginationSupport(List items, int zu\`1W^
6,b"
totalCount, int pageSize, int startIndex){ j<yiNHC
setPageSize(pageSize); P 7D!6q
setTotalCount(totalCount); F7}-!
setItems(items); _e<o7Y@_
setStartIndex(startIndex); ^+|De}`u
} | A)\
:
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publicList getItems(){ L"(4R^]
return items; {]N3f[w
} L,_.$1d
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publicvoid setItems(List items){ 7(a2L&k^
this.items = items; j;~%lg=)
} A*yi"{FLi
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publicint getPageSize(){ EG<s_d?
return pageSize; ]$iqa"{
} #1nJ(-D+
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publicvoid setPageSize(int pageSize){ o*S"KX$
this.pageSize = pageSize; X[$++p
.
} >bo'Y9C
_GYMPq\%L#
publicint getTotalCount(){ wIvo"|%
return totalCount; Vm1-C<V9
} 4@3[
%
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publicvoid setTotalCount(int totalCount){ f>$``.O
if(totalCount > 0){ Wd,a?31|
this.totalCount = totalCount; _.)eL3OF
int count = totalCount / )6X.Nfkb^k
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pageSize; aoW6U{\
if(totalCount % pageSize > 0) d l]#
count++; Yl cbW0'c
indexes = newint[count]; ki]ti={12
for(int i = 0; i < count; i++){ k ]a*&me
indexes = pageSize * 9)dfL?x8V{
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i; ib6^x:HGU
} AONDx3[
}else{ G=9d&N
this.totalCount = 0; oMH.u^b]fT
} ^%T7. 1'x
} c,\i"=!$
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publicint[] getIndexes(){ 5z$,6T
return indexes; kLSrj\6I[
} ?)4?V\$
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publicvoid setIndexes(int[] indexes){ W&Y"K)`
this.indexes = indexes; VyLH"cCv
} (=x"Y{%
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publicint getStartIndex(){ )u:Q)
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return startIndex; #o`Ny4sq/
} (]2H7X:b
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publicvoid setStartIndex(int startIndex){ +a@GHx4-
if(totalCount <= 0) %|W.^q
this.startIndex = 0; dI'SwnR
elseif(startIndex >= totalCount) JH,/jR
this.startIndex = indexes sYSLmUZ{
k"UO c=
[indexes.length - 1]; 7*o*6,/
elseif(startIndex < 0) L:nXW z
this.startIndex = 0; v-j3bB
else{ OW;tT=ql
this.startIndex = indexes o89(
h!
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[startIndex / pageSize]; qQ[b VD\*
} Ka!I`Yf
} W~n.Xeu{C
)$GIN/i
publicint getNextIndex(){ p
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int nextIndex = getStartIndex() + Dr<='Ux[5
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pageSize; m|tC24
if(nextIndex >= totalCount) DbI!l`Vn4
return getStartIndex(); UPU+ver
else ZfAzc6J?\
return nextIndex; 6]cryf&b
} }=](p-] 5
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publicint getPreviousIndex(){ /a9!Cf
int previousIndex = getStartIndex() - dhPKHrS
XUMX*
pageSize; w&h2y4
if(previousIndex < 0) ed 59B)?l
return0; Q[n\R@
else 3L>IX8_
return previousIndex; '_s}o<
} {Bvj"mL]j
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} iOw3MfO
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抽象业务类 ]:]H:U]p
java代码: +]xFoH
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/** <Cpp?DW_
* Created on 2005-7-12 b}!3;: iD
*/ QWnndI_4p
package com.javaeye.common.business; fN%jJ-[d
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import java.io.Serializable; 'Ye v}QM
import java.util.List; rsNf$v-*
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import org.hibernate.Criteria; or*HC&c7
import org.hibernate.HibernateException; @`"AHt
import org.hibernate.Session; %u\26[/
import org.hibernate.criterion.DetachedCriteria; >QE{O.Z
import org.hibernate.criterion.Projections; ^ZeJ[t&!#
import VaZn{z
*O$CaAr\s
org.springframework.orm.hibernate3.HibernateCallback; f|EUqu%E
import i%Z2wP.o
;^u*hZN[Up
org.springframework.orm.hibernate3.support.HibernateDaoS Wl"0m1G
mdih-u(T|
upport; rZ1Hf11C
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import com.javaeye.common.util.PaginationSupport; $o?@0
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public abstract class AbstractManager extends 4'pS*v
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HibernateDaoSupport { 5ABhj* 7
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privateboolean cacheQueries = false; z2c5m
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privateString queryCacheRegion; e&q?}Ho
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publicvoid setCacheQueries(boolean Iry
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cacheQueries){ a~LC+8|JW
this.cacheQueries = cacheQueries; @DAF 6ygs
} KU9Z"9#
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publicvoid setQueryCacheRegion(String 9%)=`W
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queryCacheRegion){ H5>hx{
this.queryCacheRegion = 9.O8/0w7LV
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queryCacheRegion; M[5[N{
} xG&SX#[2
t%1 ^Li
publicvoid save(finalObject entity){ O;Y:uHf
getHibernateTemplate().save(entity); ~}ml*<z@
} dj6*6qX0'^
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publicvoid persist(finalObject entity){ <-Bx&Q
getHibernateTemplate().save(entity); &<'n^n
} yR~-k?7b
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publicvoid update(finalObject entity){ 1t[j"CG(o
getHibernateTemplate().update(entity); 9a$56GnW1
} {NM+Oj,~'
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publicvoid delete(finalObject entity){ V:NI4dv/R
getHibernateTemplate().delete(entity); XJ0{
} U!w1AY|
zW |=2oX2
publicObject load(finalClass entity, lG<hlYckv
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finalSerializable id){ 8euZTfK9e
return getHibernateTemplate().load ra '
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(entity, id); %i0?UpA
} Ok-.}q>\Mv
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publicObject get(finalClass entity, >cmE
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finalSerializable id){ )
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return getHibernateTemplate().get _>o-UBb4]T
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(entity, id); Ft JjY@#
} &:*q_$]Oz
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publicList findAll(finalClass entity){ c8 K3.&P6
return getHibernateTemplate().find("from ewsKH\#
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" + entity.getName()); !hxIlVd{
} v{x{=M]
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publicList findByNamedQuery(finalString HHk)ZfWRo
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namedQuery){ 6X
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return getHibernateTemplate )o _j]K+xI
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().findByNamedQuery(namedQuery); _cDF{E+;
} _+f+`]iM
,FQdtNMap
publicList findByNamedQuery(finalString query, 2h30\/xkU
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finalObject parameter){ wYsZM/lw
return getHibernateTemplate =wu*D5
qd@&59zSh
().findByNamedQuery(query, parameter); )4Q?aMm
} |w}w.%
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publicList findByNamedQuery(finalString query, RWq{Ff}Hk
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finalObject[] parameters){ Wa/g`}
return getHibernateTemplate e59dVFug.U
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().findByNamedQuery(query, parameters); 7iC *Pr
} TTNkr`
+';>=hha
publicList find(finalString query){ "L"150Ih
return getHibernateTemplate().find {43yb_B(
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(query); (3vHY`9
} &7?R+ZGo
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publicList find(finalString query, finalObject ~!6K]hB4
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parameter){ DdV'c@rq+
return getHibernateTemplate().find iyx>q!P
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(query, parameter); '$|UwT`s
} ~o3Hdd_#}N
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public PaginationSupport findPageByCriteria }7<5hn E
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h
(final DetachedCriteria detachedCriteria){ [K~]&
return findPageByCriteria i hL/n
@* 1U{`
(detachedCriteria, PaginationSupport.PAGESIZE, 0); TrVWv
} =#5D(0Ab
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public PaginationSupport findPageByCriteria Ru!He,k7
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(final DetachedCriteria detachedCriteria, finalint 46jh-4)<
RH)EB<PV
startIndex){ Tz&Y]#h_
return findPageByCriteria wy1X\PJjH
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(detachedCriteria, PaginationSupport.PAGESIZE, ,M !tm7
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startIndex); wl=61Mb
} tEd.'D8 s
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public PaginationSupport findPageByCriteria %u{W7
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(final DetachedCriteria detachedCriteria, finalint igf)Hb;5
!%mAh81{&/
pageSize, +y+"Fyl
finalint startIndex){ xk~IN%\
return(PaginationSupport) z1OFcqm
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getHibernateTemplate().execute(new HibernateCallback(){ < O*6T%;
publicObject doInHibernate ;d.K_P
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(Session session)throws HibernateException { 5}ie]/[|
Criteria criteria = = iB,["s
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detachedCriteria.getExecutableCriteria(session); Q3W#`6jpF
int totalCount = aAvsb$
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((Integer) criteria.setProjection(Projections.rowCount n#Dv2 E=6
gB,G.QM*6
()).uniqueResult()).intValue(); :S@1
criteria.setProjection w^k;D,h
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(null); \h<BDk*
List items = x LBQ
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criteria.setFirstResult(startIndex).setMaxResults Cm$1$?J
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(pageSize).list(); }0hL~i
PaginationSupport ps = R$kpiqK
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new PaginationSupport(items, totalCount, pageSize, ^(}585b
NMO-u3<6.
startIndex); Z[!d*O%R_
return ps; Ey{%XR+*;
} 1iT\df
}, true); 23(=Xp3;>
} 73A)lU.
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public List findAllByCriteria(final .ujT!{>v/
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DetachedCriteria detachedCriteria){ " }gVAAvc7
return(List) getHibernateTemplate q}uHFp/J
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().execute(new HibernateCallback(){ +!-~yf#RE
publicObject doInHibernate h~U02"$
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(Session session)throws HibernateException { kyh_9K1
Criteria criteria = u
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detachedCriteria.getExecutableCriteria(session); 8 S`9dSc
return criteria.list(); 3Rg}+[b
} fyz
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}, true); /NT[ETMk+
} @(``:)Z<b
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public int getCountByCriteria(final a>4uiFiv
( fD
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DetachedCriteria detachedCriteria){ h 6G/O`:
Integer count = (Integer) >>[/UFC)n
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getHibernateTemplate().execute(new HibernateCallback(){ M/D)".;
publicObject doInHibernate B
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(Session session)throws HibernateException { LgmvKW|
Criteria criteria = &MR/6"/s
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detachedCriteria.getExecutableCriteria(session); vqslirC
return P=L$;xgp
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criteria.setProjection(Projections.rowCount _,Fny_u=;
q+SD6qM
()).uniqueResult(); u/b7Z`yX}
} kID[#g'
}, true); b/$km?R
return count.intValue(); :vx$vZb
} A|#`k{+1-
} IJOvnZ("A
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用户在web层构造查询条件detachedCriteria,和可选的 ";[iZ
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 U8#xgz@
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PaginationSupport的实例ps。 4:3rc7_
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ps.getItems()得到已分页好的结果集 >$67 7
ps.getIndexes()得到分页索引的数组 >t,M
ps.getTotalCount()得到总结果数 >!e<}84b
ps.getStartIndex()当前分页索引 c97{Pu
ps.getNextIndex()下一页索引 uaw~r2
ps.getPreviousIndex()上一页索引 ?[TfpAtQ`
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9 A,Z|q/z5
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 RT/o$$
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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 %\O#&=$E
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一下代码重构了。 snM Z0W
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我把原本我的做法也提供出来供大家讨论吧: FQ%c~N
@K223?c8l
首先,为了实现分页查询,我封装了一个Page类: qIUfPA=/_
java代码: 6\7ncFO3
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x} /,yaWZ
/*Created on 2005-4-14*/ uhH^>z
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package org.flyware.util.page; Zd^6ulx
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/** Eh</? Qv\
* @author Joa s>_V
* A$0H
.F>
*/ 8VG!TpX/B
publicclass Page { -W{DxN1
&K_)#v`|
/** imply if the page has previous page */ Tl]e%A`|
privateboolean hasPrePage; vD/NgRBww
nL@KX>
/** imply if the page has next page */ M4LP$N
privateboolean hasNextPage; :,;K>l^U
l:;PXy6)
/** the number of every page */ 'k;4 j|<
privateint everyPage; B0$:b!
_CBWb
/** the total page number */ e"]8T},
privateint totalPage; x_=n-lAF
qs\2Z@;
/** the number of current page */ )C(>H93
privateint currentPage; NqHy%'R
{_N,=DQ!
/** the begin index of the records by the current %V&n*3
T#%/s?_>.
query */ Sgim3):Z
privateint beginIndex; C`=p+2I]
r;9 r!$d
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/** The default constructor */ y4Z&@,_{
public Page(){ $CTSnlPq
*b *G2f^
} 682Z}"I0
eg<bi@C1|
/** construct the page by everyPage \}6;Kf}\
* @param everyPage 3<=,1 cU
* */ spU)]4P&
public Page(int everyPage){ 0tISXu-
this.everyPage = everyPage; bawJ$_O_
} "xcX'F^
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/** The whole constructor */ m^' uipa\
public Page(boolean hasPrePage, boolean hasNextPage, lN,/3\B
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=4uSFK_L
int everyPage, int totalPage, AIb2k
int currentPage, int beginIndex){ xX3'bsN
this.hasPrePage = hasPrePage; ^
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this.hasNextPage = hasNextPage; ~vLW.:
this.everyPage = everyPage; dpQG[vXe
this.totalPage = totalPage; { pu85'DV
this.currentPage = currentPage; ERwHLA
this.beginIndex = beginIndex; V^y^
;0I}[
} =/<LSeLxH
T@}|zDC#
/** .)1_Ew
* @return hPq%Lc
* Returns the beginIndex. g&dPd7
*/ IcP)FB4
publicint getBeginIndex(){ 4=uhh
return beginIndex; 64Lx-avf
} R [H+qr
}'r[m5T
/** !-s!f&_
* @param beginIndex ,1'4o3
* The beginIndex to set. pZ`|iLNl-
*/ =_j vk.
publicvoid setBeginIndex(int beginIndex){ FYs)MO
this.beginIndex = beginIndex; umz;F
} xw{-9k-~
A5,t+8`aci
/** *5tO0_L
* @return EM>}0V
* Returns the currentPage. %h1N3\y9i(
*/ yx V:!gl
publicint getCurrentPage(){
IUR<.Y`
return currentPage; t+oJV+@
} ld$i+6|
=4GSg1Biy
/** |6Gm:jV
* @param currentPage +q6ydb,
* The currentPage to set. '`'GK&)
*/ =b;>?dP
publicvoid setCurrentPage(int currentPage){ IH$0)g;s
this.currentPage = currentPage; b~dIk5>O
} Q1V9PRZX
sLE#q+W
/** 2r$#m*
* @return IwGqf.!.>
* Returns the everyPage. rt
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*/ H>r!i4l
publicint getEveryPage(){ 3_JCU05H}
return everyPage; TW !&p"Us+
} hdTzCfeZ5@
%;#^l+UB
/** cj11S>D
* @param everyPage iy""(c
* The everyPage to set. >#ZUfm{k$
*/ ^
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publicvoid setEveryPage(int everyPage){ ;lYHQQd!,
this.everyPage = everyPage; P`r55@af4
} d[rv1s>i
9@Cv5L?p\
/** bINvqv0v
* @return d1[ZHio2c?
* Returns the hasNextPage. P%K4[c W~
*/ Wg`R_>qQSm
publicboolean getHasNextPage(){ ZiLj=bh
return hasNextPage; ;#w3{
NB
} 0M\D[mg
j,]Y$B
/** RK w$- 7O
* @param hasNextPage 8Lw B
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* The hasNextPage to set. m N8pg4
*/ F R|&^j6
publicvoid setHasNextPage(boolean hasNextPage){ ~
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this.hasNextPage = hasNextPage; phO;c;y}
} `y+tf?QN
hy|b6wF&
/** `est|C '+
* @return e<r,&U$
* Returns the hasPrePage. Z|}G6]h
*/ $XoQ]}"O
publicboolean getHasPrePage(){ o M Zq+>
return hasPrePage; U`hY{E;
} K98i[,rP
YKQr,
Now
/** uwlr9nB
* @param hasPrePage \d::l{VB
* The hasPrePage to set. @JdZ5Q
*/ Haqm^Ky$
publicvoid setHasPrePage(boolean hasPrePage){ >:lnt /N3
this.hasPrePage = hasPrePage; e}1uz3Rh
} ^pHq66d%Z
},|M9I0
/** H#ClIh?'b
* @return Returns the totalPage. L5MzLE&~
* T0]MuIJ).
*/ _V`DWR
*
publicint getTotalPage(){ JU&+c6>
return totalPage; g}]t[}s1]
} # W"=ry3{
EYA,hc
/** Dc)dE2
* @param totalPage s.8{5jVG
* The totalPage to set. :6%Z]tt
*/ B7imV@<
publicvoid setTotalPage(int totalPage){ s&j-\bOic9
this.totalPage = totalPage; =hl }.p
} DK}"b}Fvq
gCyW Vp
} {T].]7Z
D= 7c(
4>J
y+7PwBo%e
'(/7[tJ
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 yr,=.?C-
{s;U~!3aY
个PageUtil,负责对Page对象进行构造: <_Q1k>
java代码: d^`?ed\1
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@V!r"Bkg.
/*Created on 2005-4-14*/ bV"G~3COy
package org.flyware.util.page; p)+k=b
n0is\ZK 0
import org.apache.commons.logging.Log; NFv>B>
import org.apache.commons.logging.LogFactory; ^Ox3XC
zl`h~}I
/** Wl}&?v&@
* @author Joa 7F'`CleU
* c [5KG}
*/ &4_qF^9J
publicclass PageUtil { i&n'N8D@
/t(C>$ }p
privatestaticfinal Log logger = LogFactory.getLog &iV{:)L
dUsxvho
(PageUtil.class); --DoB=5%8
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/** "Iix
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* Use the origin page to create a new page g&{9VK6.
* @param page =z8f]/k*>
* @param totalRecords i7ly[6{^pr
* @return VH:]@x//{
*/ yDGVrc'
publicstatic Page createPage(Page page, int GAAm0;
{^N[("`
totalRecords){ P67o{EdK
return createPage(page.getEveryPage(), 5scEc,JCi
B-r0"MX&
page.getCurrentPage(), totalRecords); M>/Zbnq
} aCL!]4K84$
jq!tT%o*B
/** SCTA=l.
* the basic page utils not including exception K^R,Iu/M
@$z<i `4
handler e>AE8T
* @param everyPage dh $bfAb
* @param currentPage XO'l Nb.
* @param totalRecords .rf"
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* @return page =lpQnj"
*/ @K!&qw
publicstatic Page createPage(int everyPage, int !Ta>U^7
1</kTm/Qa
currentPage, int totalRecords){ [
I/<_AT#
everyPage = getEveryPage(everyPage); QMZ)-ty"
currentPage = getCurrentPage(currentPage); v~Y^r2
int beginIndex = getBeginIndex(everyPage, +[tP_%/r'^
}m-FGk
currentPage); ^7Fh{q4IE
int totalPage = getTotalPage(everyPage, 5+wAzVA
|ely|U. Tf
totalRecords); vEn4L0D
boolean hasNextPage = hasNextPage(currentPage, 7>~5jYP
of@#:Qs
totalPage); c}0@2Vf
boolean hasPrePage = hasPrePage(currentPage); ,f&5pw
=
[2Ud]l:6E
returnnew Page(hasPrePage, hasNextPage, ivz{L-
everyPage, totalPage, -(b kr+N
currentPage, <Z/x,-^*<
r4#o+qE
beginIndex); Ggb5K8D*
} <=,6p>Eo[
-uy`!A
privatestaticint getEveryPage(int everyPage){ pf7it5
return everyPage == 0 ? 10 : everyPage; [#sz WNfU
} cSm%s
B9J&=6`)
privatestaticint getCurrentPage(int currentPage){ ;"m ,:5%
return currentPage == 0 ? 1 : currentPage; Xp}Yw"7
} jfqopiSi
~appY Av
privatestaticint getBeginIndex(int everyPage, int /QJ?bD#a
DX|#
gUAm
currentPage){ f^.AD-
return(currentPage - 1) * everyPage; EEW_gFn
} jNC4_q&
y? co|
privatestaticint getTotalPage(int everyPage, int 2TA*m{\Hr
L5\WpM=
totalRecords){ eET}r24
int totalPage = 0; \(vY%DL1:
v 7x:dcV
if(totalRecords % everyPage == 0) N~xLu8,
totalPage = totalRecords / everyPage; X'"SVO.
else )d>!"JB-
totalPage = totalRecords / everyPage + 1 ; PKzyV ;
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return totalPage; J`^I./
} oo.2Dn6z
}O4^Cc6
privatestaticboolean hasPrePage(int currentPage){ q')R4=0
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return currentPage == 1 ? false : true; `kJ^zw+
} `{xNXH]@
aUtnR<6
privatestaticboolean hasNextPage(int currentPage, uF3qD|I\
t0T"@t#c
int totalPage){ @$+ecaVW
return currentPage == totalPage || totalPage == qhz]Wm P
QD>"]ap,o
0 ? false : true; >:|q&|x-
} <|Pun8j
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r'*}TM'8
} 1[vi.
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#gcF"L||
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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。 #*(td<Cp
_Iv6pNd/
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 %$Aqle[
heK7pH7;d
做法如下: n;T7= 1_"
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 sK5r$Dbr
a)'5Nw9*
的信息,和一个结果集List: %&Q$dzgb_
java代码: aWY
gR
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4sT88lG4n
/*Created on 2005-6-13*/ HZf/CE9T
package com.adt.bo; '4#}e[e
wL:flH@
import java.util.List; 3z&Fi;<+j
"UJ
S5[7$
import org.flyware.util.page.Page; & J2M1z%
CLJ;<
/** Uh):b%bS;J
* @author Joa HI11Jl}{
*/ =^5Alba/
publicclass Result { KW^7H
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private Page page; &Ob!4+v/GP
$
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private List content; q*7VqB
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/** ] A+?EE2/
* The default constructor )(384@'"u
*/ A'&K/) Z
public Result(){ 07^iP>?
super(); ptZ <ow&
} ?TKRjgW`@_
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/** SF<c0bR9
* The constructor using fields %Va!\#
* `.Qi?* ^
* @param page pxh"B\"4*
* @param content bq:(u4 3
*/ I\$X/t +dH
public Result(Page page, List content){ Nu?-0>
this.page = page; K%RxwM
this.content = content; #a8B/-
}
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@-!}BUs?
/** suzZdkMA
* @return Returns the content. 65aK2MS@
*/ !74S
publicList getContent(){ 1BpiV-]=
return content; hj.a&%
} bKN@j'M
<yH4HY
/** +yD`3`
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* @return Returns the page. <,e+
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*/ v63"^%LX
public Page getPage(){ ?I~()]k5
return page; cLsV`@J(k
} @8ppEFw
`6]%P(#a
/** 5MtLT#C3r
* @param content n' q4
* The content to set. S9~+c
*/ &b%zQ4%d-`
public void setContent(List content){ PC-"gi=h
this.content = content; +2&@x=xy
} a+Kj1ix
N%*5 T[.
/** tAv@R&W,
* @param page e(GP^oK
* The page to set. 9E"vN
*/ O%5
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publicvoid setPage(Page page){ &N\jG373
this.page = page; qfMo7e@6*
} [8*jw'W|[
} ^!<BQP7
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h1B16)
r[b(I@T+
SfaQvstN
2. 编写业务逻辑接口,并实现它(UserManager, 2;DuHO1
D)m5
UserManagerImpl) M$>1L
java代码: 3 +G$-ru
bj>v|#r^
rzm:Yx
/*Created on 2005-7-15*/ 4O )1uF;
package com.adt.service; v{ 0=
x"gd8j]s
import net.sf.hibernate.HibernateException; %B5wH_p
}:KEj_~.
import org.flyware.util.page.Page; zGAq-<
_0]S69lp
import com.adt.bo.Result; #/Vh|UeX
PE3vQH=t~
/** mR?5G:W~R
* @author Joa 9NQlI1Wz4
*/ 5#+^E{
publicinterface UserManager { !y@NAa0
sP;nGQ.eN
public Result listUser(Page page)throws NnDxq%l%
10q'Z}34
HibernateException; $ us]35Z3
Af'" 6BS
} ]v]qChZHd
e
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WSp
oPXkYW
o:3dfO%nuM
java代码: iB%gPoDCL@
w~"KA6^
Kgi<UkFP
/*Created on 2005-7-15*/ X[&Wkr8x '
package com.adt.service.impl; P(,p'I;j
DVB{2~7 4
import java.util.List; -ZRO@&tMD
N343qU
import net.sf.hibernate.HibernateException; Py@wJEo
OZ
|IA:,}
import org.flyware.util.page.Page; qUob?|
^
import org.flyware.util.page.PageUtil; 2\jPv`Ia
LWz&YF#T-
import com.adt.bo.Result; /
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import com.adt.dao.UserDAO; =/y]d<g
import com.adt.exception.ObjectNotFoundException; a1+#3X.
import com.adt.service.UserManager; X[PZg{
2[RoxKm
/** %.^_Ps0
* @author Joa T_@K&<
*/ @` 1Ds
publicclass UserManagerImpl implements UserManager { *E/`KUG]
{=!b/l;@
private UserDAO userDAO; QLEKsX7p>
ktFhc3);!
/** k@f g(}6
* @param userDAO The userDAO to set. OwH81#
*/ t<z`N-5*
publicvoid setUserDAO(UserDAO userDAO){ c#Sa]n
this.userDAO = userDAO; q_g+Jf
P-D
} )4gJd?
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/* (non-Javadoc) LcSX *MC
* @see com.adt.service.UserManager#listUser Crho=RJPR
%|g>%D3Z?
(org.flyware.util.page.Page) TDFkxB>
*/ #LL?IRH9^
public Result listUser(Page page)throws _aad=BrMK
k.vBj~xU
HibernateException, ObjectNotFoundException { 9F)z4
int totalRecords = userDAO.getUserCount(); J'SZ
if(totalRecords == 0) wsIW
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throw new ObjectNotFoundException &,c``z
ZUVA EH%
("userNotExist"); PE}:ybsX
page = PageUtil.createPage(page, totalRecords); l_P-j96WD
List users = userDAO.getUserByPage(page); {*0<T|<n
returnnew Result(page, users); ![YX]+jqNp
} @eD):Y
tD(7^GuR
} yp KUkH/
hb zC#@q
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F)&@P-9+
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ]iN'x?Fo
:PIF07$xl
询,接下来编写UserDAO的代码: rz wF~-m +
3. UserDAO 和 UserDAOImpl: Oiz ,w7LRh
java代码: Ljxz.2LGr
tyXuG<
s+,OxRVw(
/*Created on 2005-7-15*/ Zhh2v>QOy
package com.adt.dao; ?s\:hNNY
~$:|VHl
import java.util.List; &x[E;P*Fg
}!"A! ~&
import org.flyware.util.page.Page; P&9Gga^I
< Z{HX[y
import net.sf.hibernate.HibernateException; L;VoJf
Co (.:z~
/** xO^:_8=&:
* @author Joa =vQcYa
*/ HJXT9;w
publicinterface UserDAO extends BaseDAO { !UG
7Uer
4
N H
publicList getUserByName(String name)throws A+SE91m
xy5lE+E_U
HibernateException; ,&jhlZ i
a`&f
publicint getUserCount()throws HibernateException; { /K.3
WN{ 9
publicList getUserByPage(Page page)throws D7lK30
4]G?G]lS>
HibernateException; @wpN6 /
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} \>jLRb|7Ts
MBt9SXM
~$iIVJ`
!V"<U2
!>{G,\^=pT
java代码: TH; R
& -{DfNK c
]h>_\9qO
/*Created on 2005-7-15*/ L\)ZC
package com.adt.dao.impl; -yE/f2PgQ
QrB@cK]
import java.util.List; KM}f:_J*lg
qfL~Wp2E;
import org.flyware.util.page.Page; Ge-CY
tk!t
Y8j
import net.sf.hibernate.HibernateException; TD'L'm|2
import net.sf.hibernate.Query; aGJC1x
6l5:1|8b,!
import com.adt.dao.UserDAO; 'MEz|Z
U}6.h&$
/** OTGofd2zf
* @author Joa <KE 1f7c
*/ )~+E[|
public class UserDAOImpl extends BaseDAOHibernateImpl +=q$ x Ia
Xf02"PXC
implements UserDAO { : >6F+XZ
MHh~vy'HB5
/* (non-Javadoc) Wc,~ {
* @see com.adt.dao.UserDAO#getUserByName w.H%R-Be
OUeyklw
(java.lang.String) RIb4!!',c
*/ )-0kb~;|
publicList getUserByName(String name)throws $nb[G$
3a?o3=
HibernateException { (8Bk;bd
String querySentence = "FROM user in class x^kp^
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&