Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 9\Ff z&
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 MRo_An+
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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 q!U$\Q&
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 \5<Z [#{
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。 (AjgLNB
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分页支持类: fsEQ4xN'
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java代码: YSPUQ
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package com.javaeye.common.util; #d[Nm+~ko
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import java.util.List; t~ I;IB
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publicclass PaginationSupport { K@[Hej6d
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publicfinalstaticint PAGESIZE = 30; <{ v
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privateint pageSize = PAGESIZE; 7p!f+\kM
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privateList items; JURu>-i
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privateint totalCount; HWFTI /]
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privateint[] indexes = newint[0]; '/loJz 1
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privateint startIndex = 0; U8>4Cl J4
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public PaginationSupport(List items, int vAop#V
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totalCount){ 0x*|X@6\
setPageSize(PAGESIZE); o>+ mw| {
setTotalCount(totalCount); x{ `{j'
setItems(items); 3]}RjOTU
setStartIndex(0); M?('VOy)
} Br<lP#u=G
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public PaginationSupport(List items, int 4DL2
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a0A=R5_
totalCount, int startIndex){ * Z)j"i
setPageSize(PAGESIZE); 4|Y1W}!0/
setTotalCount(totalCount); 1VG]|6f
setItems(items); t(6i4c>
setStartIndex(startIndex); wRK27=\z
} |${ImP
:6(@P1vA 6
public PaginationSupport(List items, int 47{5{/B-
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totalCount, int pageSize, int startIndex){ {=J:
setPageSize(pageSize); }C["'tLX
setTotalCount(totalCount); |}YxxeAk
setItems(items); G9jf]Ye;
setStartIndex(startIndex); )'7Qd(4WT
} O+<+yQl
"8?Fl&=Q
publicList getItems(){ Dz2Z
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return items; }Cfl|t<5f
} |-*50j l
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publicvoid setItems(List items){ U%BtBPL
this.items = items; )OQ<H.X
} ?0sTx6x@
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publicint getPageSize(){ n?D/bX p
return pageSize; ?5};ONjN
} 7l*vmF6Z
U6H3T0#
publicvoid setPageSize(int pageSize){ /f oI.S
this.pageSize = pageSize; NZ8X@|N
} L"S2+F)n
B2LXF3#/
publicint getTotalCount(){ y|0/;SjV
return totalCount; Q3bU"f
} WL,2<[)Ew
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publicvoid setTotalCount(int totalCount){ w<]-~`K
if(totalCount > 0){ 1!U:M8T|
this.totalCount = totalCount; jyyig%
int count = totalCount / Xj30bt
Y+$]N:\F\
pageSize; )~"0d;6_
if(totalCount % pageSize > 0) 5efN5Kt
count++; BOA7@Zaa$p
indexes = newint[count]; 7042?\\=
for(int i = 0; i < count; i++){ a
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indexes = pageSize *
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i; >X:!Y[N
} K]yWpW
}else{ ",Mrdxn7
this.totalCount = 0; 9FNsW$b?
} /$\8?<Pc".
} z"7X.*]
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publicint[] getIndexes(){ jRDvVV/-wr
return indexes; %{^|Av1Uz
} [,ulz4"
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publicvoid setIndexes(int[] indexes){ Q9f5}
this.indexes = indexes; uz$p'Q
} {wz_ngQ
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publicint getStartIndex(){ fF#Fc&B
return startIndex; rL+.3ZO):P
} SGy2&{\Z
H~Uy/22aQy
publicvoid setStartIndex(int startIndex){ (LXYx<
if(totalCount <= 0) fshG ~L7S9
this.startIndex = 0; y[AB,Dd
elseif(startIndex >= totalCount) uD{ xs
this.startIndex = indexes s0x/2z
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[indexes.length - 1]; v&]yzl
elseif(startIndex < 0) ~>0H
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this.startIndex = 0; i tk/1
else{ tW-[.Y -M,
this.startIndex = indexes w"QZ7EyJ
2cGiE{
[startIndex / pageSize]; bNm]h.
} >O~V#1 H
} ` ` Yk
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publicint getNextIndex(){ @}{uibLD\
int nextIndex = getStartIndex() + .O#7X
w?N>3`Jnf
pageSize; n6Z!~W8
if(nextIndex >= totalCount) bt.3#aj
return getStartIndex(); N@!PhP
else Ix@B*Xz:`
return nextIndex; gsa@ci
} vMJ(Ll7/
oaILh
publicint getPreviousIndex(){ 5U]@
Y?
int previousIndex = getStartIndex() - 6zNWDUf
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pageSize; Pq(LW(
if(previousIndex < 0) cyabqx
return0; i`vy<Dvpz
else utC^wA5U~
return previousIndex; M:& %c3
} l2dj GZk
cF9oo%3
} C6@*l~j
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tc\ZYCFr
FDGG$z?>m
抽象业务类 n^5Q
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java代码: s&$e}yxVO
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/** !)W#|sys&
* Created on 2005-7-12 ]Ge>S?u
*/ Y(?SE< 4R
package com.javaeye.common.business; |68/FJZ,5
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import java.io.Serializable; ObS#aRq
import java.util.List; &uBfsa$
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import org.hibernate.Criteria; W5:fY>7
import org.hibernate.HibernateException; ,7k1n{C)
import org.hibernate.Session; ~.0'v [N
import org.hibernate.criterion.DetachedCriteria; =9^}>u
import org.hibernate.criterion.Projections; w8J8III\~
import Zt=P 0
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org.springframework.orm.hibernate3.HibernateCallback; EdSUBoWF}
import zM<L_l&
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org.springframework.orm.hibernate3.support.HibernateDaoS "^wIoJ6H'
I,)\506
upport; oK4xRv8Hd
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import com.javaeye.common.util.PaginationSupport; V3d$C&<(
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public abstract class AbstractManager extends {{gt>"D,
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HibernateDaoSupport { |R!ozlL{}
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privateboolean cacheQueries = false; 49}WJC7
)
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privateString queryCacheRegion; , `EOJ"|
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publicvoid setCacheQueries(boolean a1%}Ee
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cacheQueries){ }_^ vvu
this.cacheQueries = cacheQueries; I'p+9H$
} }4h0{H
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publicvoid setQueryCacheRegion(String yaWY>sB
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queryCacheRegion){ x7`+T1IJ
this.queryCacheRegion = ;)P=WS:=
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queryCacheRegion; k#8`996P
} bw7g L\*
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publicvoid save(finalObject entity){ VEn3b
getHibernateTemplate().save(entity); r
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} {d0-.
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publicvoid persist(finalObject entity){ Fpeokr"i
getHibernateTemplate().save(entity); de.f?y
} rX>b R/
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publicvoid update(finalObject entity){ 8ZM#.yBB
getHibernateTemplate().update(entity); GU/-L<g
} P4eH:0=#
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publicvoid delete(finalObject entity){ |>m'szca4
getHibernateTemplate().delete(entity); 8c_X`0jy
} i?uX'apk
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publicObject load(finalClass entity, @7.7+blS"H
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finalSerializable id){ Ht\2 IP
return getHibernateTemplate().load "Jg.)1Jw
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(entity, id); k_zn>aR$F
} 4gNN "
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publicObject get(finalClass entity, :M f8q!Q'
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finalSerializable id){ l"DHG`kb
return getHibernateTemplate().get ,R3TFVV!?
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(entity, id); {&B_b|g*fW
} )|k#cT{=M
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publicList findAll(finalClass entity){ 0( A ?&
return getHibernateTemplate().find("from H{S+^'5Y.
]*lZFP~
" + entity.getName()); <p/2 hHfiD
} !IO\g"y~|%
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publicList findByNamedQuery(finalString lcjOBu
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namedQuery){ j6XHH&ZEb
return getHibernateTemplate {2D|,yH=
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().findByNamedQuery(namedQuery); ,r]H+vWS
} ]j6K3
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publicList findByNamedQuery(finalString query, 8TP~=qU
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finalObject parameter){ yg*
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return getHibernateTemplate W83PMiN"T-
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().findByNamedQuery(query, parameter); Hs:zfvD
} [[6"qq
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publicList findByNamedQuery(finalString query, WWZ<[[ >
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finalObject[] parameters){ bDJ!Fc/
return getHibernateTemplate _od /)#
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().findByNamedQuery(query, parameters); )z18:C3
} u~Po5W/i
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publicList find(finalString query){ a7F_{Mm
return getHibernateTemplate().find -$0}rfX
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(query); <g;,or#$
} e!gNd>b {
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publicList find(finalString query, finalObject Kl%[f jI)
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parameter){ SOM? 0.
return getHibernateTemplate().find C/qKa[mg
@fp@1n
(query, parameter); 3\
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}
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public PaginationSupport findPageByCriteria pI8z.JD
Tj_K5uccU}
(final DetachedCriteria detachedCriteria){ UXdc'i g
return findPageByCriteria GIc q|Pe
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); YI"!&a'yj
} X';qcn_^
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public PaginationSupport findPageByCriteria ,pdzi9@=t
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(final DetachedCriteria detachedCriteria, finalint CLVT5pj='
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startIndex){ FK~wr;[
return findPageByCriteria rOt{bh6r
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(detachedCriteria, PaginationSupport.PAGESIZE, T&>65`L
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startIndex); @<pd@Mpf]
} R8u8jG(4
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public PaginationSupport findPageByCriteria [ij) k@.
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(final DetachedCriteria detachedCriteria, finalint {nUmlP=mS
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pageSize, xt pY*
finalint startIndex){ 1v.#ndk
return(PaginationSupport) :.XlAQR~b
*P/A&"i[E
getHibernateTemplate().execute(new HibernateCallback(){ o4EY2
publicObject doInHibernate S|k@D2k=
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(Session session)throws HibernateException { tugIOA
Criteria criteria = 0[%{YmI{W
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detachedCriteria.getExecutableCriteria(session); w`f66*@Q1
int totalCount = mH ju$d
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((Integer) criteria.setProjection(Projections.rowCount I5l%X{u"N
JkT!X
()).uniqueResult()).intValue(); 85Yi2+8f4
criteria.setProjection H7&y79mB
.*njgAq7
(null); \-6y#R-B
List items = ^"
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criteria.setFirstResult(startIndex).setMaxResults OhCdBO
\9#f:8Q
(pageSize).list(); +[uh);vD`G
PaginationSupport ps = 1
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new PaginationSupport(items, totalCount, pageSize, 3I( n];
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startIndex); p qpsa'
return ps; ?#: ']q
} vvxD}p=y
}, true); Lv/}&'\(
} u;rmqo1
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public List findAllByCriteria(final L3wj vq^
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DetachedCriteria detachedCriteria){ ^K1mh9O
return(List) getHibernateTemplate xPUukmG:B
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().execute(new HibernateCallback(){ S>(x x"Ia
publicObject doInHibernate H.{Fw j4
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(Session session)throws HibernateException { %pOz%v~
Criteria criteria = tg#jjXV\0p
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detachedCriteria.getExecutableCriteria(session); 6 *S/frE
return criteria.list(); *#}=>, v
} \{ QH^
}, true); (EWGX |QA
} E`^D9:3:)
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public int getCountByCriteria(final TK'
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DetachedCriteria detachedCriteria){ oz{X"jfu
Integer count = (Integer) Ar/P%$Zfq
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getHibernateTemplate().execute(new HibernateCallback(){ hkb\GcOj
publicObject doInHibernate }DjVZ48
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(Session session)throws HibernateException { $+44US
Criteria criteria = 13v`rK`7o
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detachedCriteria.getExecutableCriteria(session); ETL7|C"
return 6-"tQ,AZ
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criteria.setProjection(Projections.rowCount s-WZ3g
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()).uniqueResult(); <HRPloVKo
} ,{q#U3
}, true); 0.R3(O
return count.intValue(); &XCd2
} iN'T^+um=
} C/N;4
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用户在web层构造查询条件detachedCriteria,和可选的 6o6yx:
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 |?0MRX0'g
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PaginationSupport的实例ps。 6vNn;-gg.
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ps.getItems()得到已分页好的结果集 %{r3"Q=;W
ps.getIndexes()得到分页索引的数组 zB+e;x f |
ps.getTotalCount()得到总结果数 C,>n
ps.getStartIndex()当前分页索引 8NNh8k#6
ps.getNextIndex()下一页索引 D}!YF~
ps.getPreviousIndex()上一页索引 DQ= {
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 o ?05bv
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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 @YaI5> ,/
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一下代码重构了。 vYXh WqL~
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我把原本我的做法也提供出来供大家讨论吧: hC<E4+5.,
mpwh=
首先,为了实现分页查询,我封装了一个Page类: {_\dwe9
java代码: 5X];?(VTsb
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/*Created on 2005-4-14*/ A~E S{Zkh
package org.flyware.util.page; 8irTGA
+[n#{;]<
/** v.:Q& ]
* @author Joa (HeSL),1
* Pr%KcR ;
*/ E,?IIRg&
publicclass Page { zpf<!x^
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/** imply if the page has previous page */ 4`oKvL9
privateboolean hasPrePage; gk8v{'0Er
7vPGb:y
/** imply if the page has next page */ .HY,'oC.
privateboolean hasNextPage; It/'R-H
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/** the number of every page */ $;ny`^8
privateint everyPage; |p*cI @
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/** the total page number */ d<OdQvW.
privateint totalPage; qu$FpOJ
kl1Q:
/** the number of current page */ {GT5
privateint currentPage; ea$. +
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/** the begin index of the records by the current 'cS| BT
X5+^b({
query */ mhU=^/X
privateint beginIndex; xp3^,x;\X
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/** The default constructor */ 5'{QMnfB
public Page(){ L)7{_s
~qL/P 5*+
} w-km
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/** construct the page by everyPage Kt]vTn7!9
* @param everyPage k:j?8o3
* */ DTi^* Wj
public Page(int everyPage){ vYLspZ;S
this.everyPage = everyPage; w0sy@OF
} C.uv0
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/** The whole constructor */
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public Page(boolean hasPrePage, boolean hasNextPage, }>,%El/
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int everyPage, int totalPage, (C`nBiL<
int currentPage, int beginIndex){ %t9Kc9u3p
this.hasPrePage = hasPrePage; +",`Mb
this.hasNextPage = hasNextPage; 16z
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this.everyPage = everyPage; v=dN$B5y3
this.totalPage = totalPage; ,_7m<(/f
this.currentPage = currentPage; &DtI+)[|
this.beginIndex = beginIndex; Z!'kN\z
} g?j^d:
"<&o;x<
/** #sv}%oV,F
* @return l_2l/ff9
* Returns the beginIndex. L4u.cHJ}0
*/ Q>w)b]d~c
publicint getBeginIndex(){ wax^iL!
return beginIndex; _q@lP|
} e2nZwPH
? )IH#kL
/** |D'!.$7%
* @param beginIndex F$:mGyl5_
* The beginIndex to set. Q3t%JP>;g
*/ wc}x
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publicvoid setBeginIndex(int beginIndex){ }+[!h=Bx
this.beginIndex = beginIndex; ?"}U?m=
} 0,__{?!
slr>6o%W`
/** 0}kvuuR
* @return 3_eg'EP.E
* Returns the currentPage. f
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*/ = K`]cEL
publicint getCurrentPage(){ K6~')9Q
return currentPage; G[zy sxd
} mkBQTQGT
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/** 8|hi2Qeu,c
* @param currentPage "4*QA0As
* The currentPage to set. cZWW[i
*/ D[YdPg@-
publicvoid setCurrentPage(int currentPage){ ^:O*Sx.CA
this.currentPage = currentPage; 7
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} DuQ:82 3b
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/** @ <'a0)n>
* @return zRau/1Y0
* Returns the everyPage. FklO#+<:
*/ h{)`W
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publicint getEveryPage(){ AMK3I`=8WO
return everyPage; N=8CVI
} HE2t0sAYX
yN#]Q}4
/** ,
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* @param everyPage ,zBc-Cm
* The everyPage to set. d _=44( -
*/ ydzvjp=
publicvoid setEveryPage(int everyPage){ cf_X=;yaqy
this.everyPage = everyPage; qNkX:|j
}
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/** D@iS#+22
* @return U[@B63];0
* Returns the hasNextPage. MF::At[4
*/ g87M"kQKA
publicboolean getHasNextPage(){ xtXK3[s
return hasNextPage; Zl2doXC
} "1ZVuI
I?<ibLpX
/** kf)s3I/`(
* @param hasNextPage <|a9r: [
* The hasNextPage to set. 2l8z/o 7v
*/ -]Oi/i, {
publicvoid setHasNextPage(boolean hasNextPage){ wS:`c
J
this.hasNextPage = hasNextPage; F2=#\U$
} QVN@B[9
$)(Zt^
/** \FyHIs
* @return 3\P/4GK)
* Returns the hasPrePage. ~^eC?F(
*/ fhQ N;7
publicboolean getHasPrePage(){ C2
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return hasPrePage; `[f IK,
} -n$hm+S
7q^a@5f BG
/** xSjs+Y;Mu
* @param hasPrePage sQY0Xys<4
* The hasPrePage to set. Bq\WG=Fd
*/ c5HW.3"
publicvoid setHasPrePage(boolean hasPrePage){ LS1}j WU!
this.hasPrePage = hasPrePage; gHU0Pr9'
} <UJ5n) }"\
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/** 3],[6%w
* @return Returns the totalPage. EPeV1$
* }Ot2; T
*/ rAQ3x0
publicint getTotalPage(){ qI gb;=V
return totalPage; UrB{jS?
} 4*+)D8
&eX^ll
/** }Q>??~mVl
* @param totalPage 3ry0.
* The totalPage to set. [UaM}-eR
*/ ^(yU)k3pu
publicvoid setTotalPage(int totalPage){ Ob7F39):N
this.totalPage = totalPage;
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} -M?s<R[&
:U#4H;kk~j
} qr7_3
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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 *ps")?tlC
6rzXM`cs
个PageUtil,负责对Page对象进行构造: .AHww7
java代码: T$9tO{
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/*Created on 2005-4-14*/ QW}N,j$
package org.flyware.util.page; 'd=B{7k@
&r!*Y&
import org.apache.commons.logging.Log; '${xZrzmt
import org.apache.commons.logging.LogFactory; D&#ph%U,P
^T/d34A;SP
/** w#`E;fN'
* @author Joa
{3=]cLtt
* IH'&W
*/ FFqqAT5
publicclass PageUtil { \*$''`b)j
#+Cu&l
privatestaticfinal Log logger = LogFactory.getLog ,Tc598D
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(PageUtil.class); =P<7tsSuoK
&p#.m"Oon
/** '0>w_ge4
* Use the origin page to create a new page 2q.J1:lW
* @param page a-7T
* @param totalRecords JN-wToOF
* @return I HtNaN )
*/ c2<JS:!*
publicstatic Page createPage(Page page, int D>Dch0{H,:
1-60gI1)
totalRecords){ 8!{F6DG
return createPage(page.getEveryPage(), $17utJ58
J(\f(jh/
page.getCurrentPage(), totalRecords); Kr'5iFK7
} $&iw (BIq
-%^KDyZ<&
/** %) 8 UyZG
* the basic page utils not including exception bjEm=4FI;
&]Q\@;]Aq
handler StJ&YYdD
* @param everyPage YYUWBnf30G
* @param currentPage V8.o}BWY
* @param totalRecords 7R`:^}'>
* @return page fPW(hb;
*/ &c)n\x*
publicstatic Page createPage(int everyPage, int _+hf.[""
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currentPage, int totalRecords){ k&PxhDf
everyPage = getEveryPage(everyPage); qXJBLIG
currentPage = getCurrentPage(currentPage); &}G2;O}3
int beginIndex = getBeginIndex(everyPage, )a%kAUNj
2pEr
s|r
currentPage); Bdd>r#]
int totalPage = getTotalPage(everyPage, gIfl}Jat
"eiZZSz
totalRecords); %;|^*?!J0
boolean hasNextPage = hasNextPage(currentPage, B&E qd
~ g \GC
totalPage); Gn_rf"
boolean hasPrePage = hasPrePage(currentPage); {@c)!%2$
xi2!__
returnnew Page(hasPrePage, hasNextPage, hI{M?LQd
everyPage, totalPage, n2$(MDdL`
currentPage, +84JvOkWi
Hki
beginIndex); & A%*sD6
} -~-BQ!!(
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privatestaticint getEveryPage(int everyPage){ A[@xTqs{{
return everyPage == 0 ? 10 : everyPage; QFm~wv8:
} q;p:)Q"
VnB"0"%w
privatestaticint getCurrentPage(int currentPage){ b]Xc5Dp{
return currentPage == 0 ? 1 : currentPage; ny:4L{)
} 7]w]i5
11s*C #
privatestaticint getBeginIndex(int everyPage, int D@5AI
](
'
?3e 1
currentPage){ ivKhzU+
return(currentPage - 1) * everyPage; YVMwb@|
} GDgq
4vfj
o0Y
{k8
privatestaticint getTotalPage(int everyPage, int m4.IaBn/
kCWaji_x%
totalRecords){ <TL!iM
int totalPage = 0; !vB8Pk"
n.{Ud\|
if(totalRecords % everyPage == 0) mBC?Pg
totalPage = totalRecords / everyPage; SW
^F
else B=mk@gX,G
totalPage = totalRecords / everyPage + 1 ; *TEgV
n -P)X<\
return totalPage; #G;0yB:76
} U=4tJb
ahno$[
privatestaticboolean hasPrePage(int currentPage){ 3(De> gs$
return currentPage == 1 ? false : true; Q,#
)
} zCZ]`
Dl2`b">u
privatestaticboolean hasNextPage(int currentPage, 2`XG"[@
s3sAw~++
int totalPage){ u/5^N^@^
return currentPage == totalPage || totalPage == b42"Y,sbB
h#ogL-UU
0 ? false : true; mlsM;Ad2
} &>
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tCFXb6Cz
dy^Zlu`
f
} p<w2e
=}6yMR!4R<
6tC0F=
y6bl&_
/T53"+7:0
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。 {=5Wi|
{_GhS%
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 UQmdm$.
bT^6AtsJ
做法如下: b'1n1L
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 sOegR5?;
h JVy-]
的信息,和一个结果集List: fO+$`r>9
java代码: 1Y2]jz4
i /j
DwA
s}NE[Tw
/*Created on 2005-6-13*/ {s8v0~
package com.adt.bo; uAd4Zz
z@Klj qN
import java.util.List; aNX M~;5~
EZ6\pyNB0#
import org.flyware.util.page.Page; yHY \4OHS
.DzFtc
/** v##k,R.d
* @author Joa $IZ02ZM$
*/ PyOj{WX>W
publicclass Result { n&? --9r
D<-MbK^S
private Page page; j06q3N"
R!mFMw"
private List content; Y7TW_[_u
r5h+_&v,M
/** 5%+M:B
* The default constructor hG~TqH^}B
*/ gLyXe,Jp
public Result(){ `1AVw]k
super(); @WmEcX|
} s4RqY*VK
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/** k,p:!S(bl
* The constructor using fields /i'dhiG
* c7~+ 5
* @param page F/91Es
* @param content ^lB=O
*/ kj$Ks2!W
public Result(Page page, List content){ ,4O|{Iu#n
this.page = page; fC$Rz#5?
this.content = content; <OQn|zU\
} S}@J4}*u["
kx6AMx!nX
/** ZCP
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* @return Returns the content. :Pa^/i
*/ }XJA#@
publicList getContent(){ /$w,8pV=
return content; ,".1![b
} |ia#Elavo
nY]5pOF:
/** `7v"(
* @return Returns the page. >(>,*zP<9
*/ xL-]gwq
public Page getPage(){ JDp"!x{O
return page; zEHX:-f8
} <'{*6f@n
6ol*$Q"z
/** 'T!^H
* @param content Pdq}~um3{
* The content to set. RM\A$.5
*/ K{]9Yo
public void setContent(List content){ zWN<"[agc
this.content = content; }:04bIaV
} ,>YW7+kY
oGtz*AP%
/** ~Ox !7Lp
* @param page }Kt`du=
* The page to set. -rn%ASye
*/ K~1uR:DR
publicvoid setPage(Page page){ cdBD.sg
this.page = page; 3}Xf
} y\?T%g
} T[M:%vjYF
VLdQXNg9W"
y.iA]Ikz
wFe?0u
? Zhnb0/
2. 编写业务逻辑接口,并实现它(UserManager, Gr),o6}p
S.4gfY
UserManagerImpl) DlMT<ld
java代码: | e?:Uq
^~
95q0hq:
5_H`6-q
/*Created on 2005-7-15*/ _l{`lQ}
package com.adt.service; *VuiEBG
>/BMA;`
import net.sf.hibernate.HibernateException; AmyZ9r#{
!R`E+G@
import org.flyware.util.page.Page; 8M<\?JD~_f
e&R?9z-*
import com.adt.bo.Result; S)?V;@p6
G!G]*p5
/** lG1\41ZxB
* @author Joa y-.<iq
*/ 5YZh e4R
publicinterface UserManager { m }J@w~#
w
\ U?64
public Result listUser(Page page)throws vtA%^~0
=._V$:a6o
HibernateException; ~W>3EJghR,
A$7j B4
} ;4%Co)Rw
3J3Yt`
;4:[kv@
>bLhCgF:"
F|wT']1Y
java代码: @mD$Z09~
D8rg:,'6
dvW2X
/*Created on 2005-7-15*/ *!m\%*y{
package com.adt.service.impl; -/g<A~+i]$
Sc.@u3
import java.util.List; 1_=I\zx(
"hbCP4
import net.sf.hibernate.HibernateException; #n_ gry!5
|7$Q'3V
import org.flyware.util.page.Page; B-1Kfc
import org.flyware.util.page.PageUtil; D;Bij=
Qo5yfdR
import com.adt.bo.Result; -$A
>b8
import com.adt.dao.UserDAO; 4#Bzq3,|
import com.adt.exception.ObjectNotFoundException; X$Y\/|!z
import com.adt.service.UserManager; kgv29j?k;
)` ^/Dj;
/** S^ q%+Z
* @author Joa Hz>_tA"^T
*/ "XB6k0.#
publicclass UserManagerImpl implements UserManager { o..iT:f;n
y0R9[;b07
private UserDAO userDAO; W6A-/;S\
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/** yADX^r(
* @param userDAO The userDAO to set. N hY`_?)
*/ GzN /0:b
publicvoid setUserDAO(UserDAO userDAO){ sqv!,@*q
this.userDAO = userDAO; '}N4SrU$
} SR$?pJh D%
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/* (non-Javadoc) O'~>AC5{
* @see com.adt.service.UserManager#listUser Oj F]K,$
nw
(org.flyware.util.page.Page) sPP(>y( \
*/ i6FviZx
public Result listUser(Page page)throws W%-`
(R|_ 6[zy
HibernateException, ObjectNotFoundException { )4;$;a1
int totalRecords = userDAO.getUserCount(); 3P|z`}Ka
if(totalRecords == 0) 5L 0w!q'W
throw new ObjectNotFoundException L2Z-seE
|I2~@RfpO:
("userNotExist"); +Y_]<
page = PageUtil.createPage(page, totalRecords); <*@!>6mS
List users = userDAO.getUserByPage(page); n_/;j$h
returnnew Result(page, users); 5{|tE!
} q |Orv=v
@#>YU
} tE$oV
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V2B:
DIpr
= tY%k!R
L$3{L"/
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 7csMk5NU'<
er0y~
询,接下来编写UserDAO的代码: 9&"wfN N
3. UserDAO 和 UserDAOImpl: vWZ?*0^
java代码: iI$;%uY3g
k fY0u
\GdsQAF"
/*Created on 2005-7-15*/ w?JM;'<AYQ
package com.adt.dao; W5(.Hub}
m0,TH[HWGF
import java.util.List; ~(-df>
mum4Uj
import org.flyware.util.page.Page; cq4sgQ?sW
b~C^cM
import net.sf.hibernate.HibernateException; YfUo=ku
ZPlY]e
/** ,CP&o
* @author Joa Z5Tu*u=
*/ G4,.kK
publicinterface UserDAO extends BaseDAO { AmX ~KK
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publicList getUserByName(String name)throws `G<|5pe
o9+fAH`D
HibernateException; We@wN:
J l
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publicint getUserCount()throws HibernateException; *XkgwJq
Dq<!wtFG[
publicList getUserByPage(Page page)throws V`_)H
k&pV`.Imi
HibernateException; #^9a[ZLj0
tKCX0UZ'
} ,xg(F0q
;0nL1R]w(
{q/D,Rh8
0[92&:c,
'"9Wt@
.
java代码: 0O|l7mCr%I
F
@uOXNz)
NI2-*G_M
/*Created on 2005-7-15*/ uX8G<7O^
package com.adt.dao.impl; *d}{7UMy#
Os[50j!4>
import java.util.List; UJ^-T+fut
T5+
(F z
import org.flyware.util.page.Page; 9D
@}(t!
h9cx~/7,_)
import net.sf.hibernate.HibernateException; ^o[(F<q
import net.sf.hibernate.Query; "vo
o!&<
p sAr>:\3
import com.adt.dao.UserDAO; _YA;Nd#%k
Bi`m +ob
/** v4W<_
7L_
* @author Joa &&TAX
*/ }3S6TJ+
public class UserDAOImpl extends BaseDAOHibernateImpl $c];&)7q
6G;t:[H G
implements UserDAO { ]Vd1fkXO0
xX\A&9m
/* (non-Javadoc) c#T0n !}
* @see com.adt.dao.UserDAO#getUserByName Ht7v+lY90^
%!V =noo
(java.lang.String) g*$yUt
*/ jWGX:XB
publicList getUserByName(String name)throws wQrD(Dv(yA
RO.bh#A$
HibernateException { 7DB!s@"
String querySentence = "FROM user in class Yzih-$g
VR vX^w0
com.adt.po.User WHERE user.name=:name"; vve[.Lud'
Query query = getSession().createQuery f= 33+8I
Ya
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(querySentence); FfibR\dhY
query.setParameter("name", name); I#:,!vjn
return query.list(); &h?8yV4B
} Dlx-mm_
^e:rRk7 &
/* (non-Javadoc) M%N_4j.
* @see com.adt.dao.UserDAO#getUserCount() E)%r}4u>
*/ )B5(V5-!|
publicint getUserCount()throws HibernateException { e%v0EJ},
int count = 0; 3.D|xE]g
String querySentence = "SELECT count(*) FROM --g?`4
`l<pH<F
user in class com.adt.po.User"; =>Dw,+"
Query query = getSession().createQuery h 7*#;j
~.TKzh'eB
(querySentence); Ku;8Mx{
count = ((Integer)query.iterate().next 'Q4V(.
Y[`%j\=
()).intValue(); j(`V&S
return count; j WerX -$
} SkMBdkS9z[
IjrjLp[z$
/* (non-Javadoc) V>B*_J,z.
* @see com.adt.dao.UserDAO#getUserByPage #brV{dHV,
%^<A`Q_
(org.flyware.util.page.Page) S0mF%"
*/ @+^5ze\
publicList getUserByPage(Page page)throws
*egAx
U?yKwH^{
HibernateException { %|gj46
String querySentence = "FROM user in class ]?j[P=\
YhJ*(oWL
com.adt.po.User"; hxj[gE'R(
Query query = getSession().createQuery nY=]KU
a3(q;^v
(querySentence); H_+!.
query.setFirstResult(page.getBeginIndex()) \&1Di\eL
.setMaxResults(page.getEveryPage()); q@&.)sLPgO
return query.list(); UZ3oc[#D=]
} =]hPX
=U<6TP]{
} m/>z}d05h
\:d|'r8OCM
h2fTG
* 57y.](w
.LEn~ 8
至此,一个完整的分页程序完成。前台的只需要调用 PU{7s
]QK@zb}x
userManager.listUser(page)即可得到一个Page对象和结果集对象 9lCZi?
1
Ll<^P
的综合体,而传入的参数page对象则可以由前台传入,如果用 zFGZ;?i
SBqx_4}
webwork,甚至可以直接在配置文件中指定。 *<T,Fyc|
K)8N8Js(
下面给出一个webwork调用示例: 4f{(Scg
java代码: ]Qb85;0)
} l4d/I
_9Y7.5
/*Created on 2005-6-17*/ B;mt11M
package com.adt.action.user; @(Y+W2Iyy+
@&E{
L
import java.util.List; }!0nb)kL
"N4rh<<
import org.apache.commons.logging.Log; f3Cjj]RFv
import org.apache.commons.logging.LogFactory; UkV{4*E
import org.flyware.util.page.Page; *O@uF4+!1
~R\Z&oQ
import com.adt.bo.Result; Q)b*;
@
import com.adt.service.UserService; CkA
~'&C
import com.opensymphony.xwork.Action; ]>\!} \R<
tr$~INe
/** om'DaG`A
* @author Joa ??.9`3CYo
*/ =;"$t_t
publicclass ListUser implementsAction{ #{u>
@x
z?^20N
privatestaticfinal Log logger = LogFactory.getLog 'dTg\
Qv
.ko}m{
(ListUser.class); ^6[o$eY3
qC?\i['`
private UserService userService; N#? Ohz
$Q!J.}P@
private Page page; p4-bD_
4,pS C
privateList users; =2yg:D
_N-JRM m<
/* iSz?V$}?
* (non-Javadoc) 'aoHNZfxw
* ;'x\L<b/)
* @see com.opensymphony.xwork.Action#execute() EO[UezuU
*/ MGzuQrl{H
publicString execute()throwsException{ gAWrn^2L5
Result result = userService.listUser(page); Yh}F
page = result.getPage(); $5;RQNhXh
users = result.getContent(); 0Zv<]xO
return SUCCESS; ;\5^yDv[e
} ssy+x;<x,
[rt+KA
/** M)oJ06`K
* @return Returns the page. %7*Y@k-)o
*/ 5%E.UjC
public Page getPage(){ 47c` ) *Hc
return page; u LXV,
} k TLA["<m
`xpU
/** /:j9#kj
* @return Returns the users. 8v)PDO~D}A
*/ uJP9J U
publicList getUsers(){ `RG_FS"v
return users; %)K)h&m