Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 x{.+i'
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 fu]mxGPc
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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 H:jx_
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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 a/v!W@Zz}
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分页支持类: JX! @j3
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java代码: 3j2#'Jf|:
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package com.javaeye.common.util; /-v6jiM
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import java.util.List; . \6q\7Ej
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publicclass PaginationSupport { #lld*I"d
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publicfinalstaticint PAGESIZE = 30; U:1cbD7|3
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privateint pageSize = PAGESIZE; +thkx$o
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privateList items; k~,({T<
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privateint totalCount; <RaM@E
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privateint[] indexes = newint[0]; N">4I)
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privateint startIndex = 0; tW)KpX
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public PaginationSupport(List items, int 5zf bI
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totalCount){ o,D7$WzL
setPageSize(PAGESIZE); 6";ew:Ih^
setTotalCount(totalCount); !Yi2g-(
setItems(items); ?Xq"Q^o4#e
setStartIndex(0); |DBj<|SX
} 9N@m><N84
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public PaginationSupport(List items, int 2^;zj0]Rt
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totalCount, int startIndex){ h%*@82DKK
setPageSize(PAGESIZE); 3)6&)7`*
setTotalCount(totalCount); G3wkqd
setItems(items); "!F%X%/
setStartIndex(startIndex);
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} 9z9\pXFQ
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public PaginationSupport(List items, int j2GTo~muq
rQb=/@-
totalCount, int pageSize, int startIndex){ XTro;R=#
setPageSize(pageSize); 49?wEm#
setTotalCount(totalCount); 0`y*7.Ip
setItems(items); FJCL K#-
setStartIndex(startIndex); JOUZ"^v
} km,I75o.
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publicList getItems(){ y:Ne}S*ncE
return items; 2P(6R.8;6
} C4H$w:bVk
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publicvoid setItems(List items){ FD[o94`%
this.items = items; 3"O&IY<
} "pInb5F
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publicint getPageSize(){ ]p-xds#d
return pageSize; /a7N:Z_Bz
} xMr=tU1C
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publicvoid setPageSize(int pageSize){ ~4V-{-=0a7
this.pageSize = pageSize; fG_<HJS(~
} 4Wk`P]?^
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publicint getTotalCount(){ /:. p{y
return totalCount; r"&uW!~0
} b'1m
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#6F|}E
publicvoid setTotalCount(int totalCount){ 8c3/n
if(totalCount > 0){ N#<X"&-_#
this.totalCount = totalCount; )zv"<>Q 6
int count = totalCount / VYw<8AEFY
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pageSize; m>{I>:sq
if(totalCount % pageSize > 0) 1/tyne=m
count++; <Eu/f`8
indexes = newint[count]; JH+uBZh6
for(int i = 0; i < count; i++){ w/,A@fLL
indexes = pageSize * j^)=<+Q;=
*bl|[(pP
i; 6c[Slq!KA
} +k{l]-)1
}else{ Q79WGW
this.totalCount = 0; 8JojKH
} 9l<}`/@}W
} k!0vpps
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publicint[] getIndexes(){ ;;}}uW=
return indexes; ys- w0H
} 9WT{~PGj
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publicvoid setIndexes(int[] indexes){ SNrX(V::z
this.indexes = indexes; gHox>r6.A
} cXIuGvE&=
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publicint getStartIndex(){ E^C [G)7n
return startIndex; `1i\8s&O6@
} <~hx ~"c
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publicvoid setStartIndex(int startIndex){ #}+_Hy
if(totalCount <= 0) 'byao03
this.startIndex = 0; *]>~lO1
elseif(startIndex >= totalCount) :4x&B^,53
this.startIndex = indexes ow4|GLU^;
M Ui#3o\f
[indexes.length - 1]; Ij?Qs{V
elseif(startIndex < 0) d;g]OeF
this.startIndex = 0; S9E<)L
else{ tpQ8
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this.startIndex = indexes |[iEi
*t bgIW+h
[startIndex / pageSize]; 7b*9
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} L.x`Jpq(3
} +%H2;8{F
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publicint getNextIndex(){ Mi<}q@]e
int nextIndex = getStartIndex() + V;(Rg=5
|]'gd)%S\
pageSize; 9Idgib&
if(nextIndex >= totalCount) 5|g#>sx>`q
return getStartIndex(); hY/i)T{
else F>
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return nextIndex; *fp4u_:`
} tN_~zP
kf1 (
publicint getPreviousIndex(){ &GaI
int previousIndex = getStartIndex() - v%)=!T,
, L5.KwB
pageSize; ]D@y""{--s
if(previousIndex < 0) J@RV ^2
return0; ]ZS/9 $
else uWkuw5;
return previousIndex; "9OOyeKu%
} ]8|peo{
ar:qCq$\
} keS%w]87
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抽象业务类 6Z!OD(/e
java代码: /'L/O;H20
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/** Bw4PxJs-
* Created on 2005-7-12 vJg^uf)
*/ ,a\pdEPj
package com.javaeye.common.business; H1 e^/JD)
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import java.io.Serializable; WO+_|*&
import java.util.List; , R $ZZ4
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import org.hibernate.Criteria; =%0r_#F%=
import org.hibernate.HibernateException; X`0`A2
n
import org.hibernate.Session; ktiC*|fd
import org.hibernate.criterion.DetachedCriteria; |c:xK{Ik
import org.hibernate.criterion.Projections; ~c|{PZ9U
import AUwIF/>F(]
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org.springframework.orm.hibernate3.HibernateCallback; iYz!:TxP
import p}
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org.springframework.orm.hibernate3.support.HibernateDaoS 9 [wR/8Xm
A{ Ejk|
upport; NplkhgSj
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import com.javaeye.common.util.PaginationSupport; 7_]Bu<{f
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public abstract class AbstractManager extends (\ Gs7
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HibernateDaoSupport { > 72qi*0
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privateboolean cacheQueries = false; #3((f[
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privateString queryCacheRegion; S@vLh=65
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publicvoid setCacheQueries(boolean <m+$@:cO
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cacheQueries){ av}pT)]\
this.cacheQueries = cacheQueries; ^?gs<-)B
} k?ksv+e\
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publicvoid setQueryCacheRegion(String j:J{m0
bId@V[9
queryCacheRegion){ ,XmyC7y<
this.queryCacheRegion = S`&YY89{&
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queryCacheRegion; 9 e0Oj3!B
} ompkDl\E
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publicvoid save(finalObject entity){ "P{T]
getHibernateTemplate().save(entity); F<N{ x^
} I:,D:00+
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publicvoid persist(finalObject entity){ y1+~IjY
getHibernateTemplate().save(entity); ee{8C~
} O;~dao
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publicvoid update(finalObject entity){ f
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getHibernateTemplate().update(entity); jwZBWt )5
} w65D;9/;
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publicvoid delete(finalObject entity){ nK5FPFz8
getHibernateTemplate().delete(entity); j?'It`s
} K(B|o6[
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publicObject load(finalClass entity, :s`\jJ
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finalSerializable id){ 9?#L/
return getHibernateTemplate().load 7!-y72qx
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(entity, id); Vpsv@\@J>
} "Rv],O"
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publicObject get(finalClass entity, #OVf2
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finalSerializable id){ 5cE?>
return getHibernateTemplate().get U#U nM,3%
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(entity, id); sy;_%,}N
} c;pv< lX'
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publicList findAll(finalClass entity){ M;K%=l$NG
return getHibernateTemplate().find("from fG*366W
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" + entity.getName());
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} dy^ zOqc
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publicList findByNamedQuery(finalString V,qc[*_3
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namedQuery){ P\R#!+FgW8
return getHibernateTemplate KWH l+pL
q:/<^|
().findByNamedQuery(namedQuery); wio}<Y6Xz
} .y~vn[q N
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publicList findByNamedQuery(finalString query, zwa%$U
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finalObject parameter){ }L.&@P<
return getHibernateTemplate *c6o#[l
).b,KSi
().findByNamedQuery(query, parameter); #N'W+M /
} 1f zHmD
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publicList findByNamedQuery(finalString query, t}]R0O.s
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finalObject[] parameters){ ^yo~C3r~
return getHibernateTemplate >MeM
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().findByNamedQuery(query, parameters); ^$I8ga
} ckTk2xPQ
z nxAP|
publicList find(finalString query){ c_#+xGS!7
return getHibernateTemplate().find MQ{.%
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(query); V"`t*m$
} vz-O2B_u
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publicList find(finalString query, finalObject (7Q
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parameter){ vRQ7=N{3
return getHibernateTemplate().find #7}1W[y9}l
y:R!E *.L'
(query, parameter); m=hUHA,p4
} <)dHe:
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public PaginationSupport findPageByCriteria uVn"'p-
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(final DetachedCriteria detachedCriteria){ X5gI'u
return findPageByCriteria R@8pKCL.
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); muJR~4
} 88l\8k4r
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public PaginationSupport findPageByCriteria 9 cwy;au
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(final DetachedCriteria detachedCriteria, finalint ?8GggJC
p&nPzZQL(
startIndex){ ;"K;D@xzh]
return findPageByCriteria Fb0r(vQ^
/5$;W'I
(detachedCriteria, PaginationSupport.PAGESIZE, /)<x<7FKW
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startIndex); 4ru-qF
} x<fF1];
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public PaginationSupport findPageByCriteria QU;bDNq,c
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(final DetachedCriteria detachedCriteria, finalint c&GVIrJ
[ <,i}z
pageSize, `UK'IN.il
finalint startIndex){ ]9P2v X
return(PaginationSupport) #@3&1}J/
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getHibernateTemplate().execute(new HibernateCallback(){ Ok V*,n
publicObject doInHibernate 7H l>UX,|
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(Session session)throws HibernateException { U7do,jCoa
Criteria criteria = L]kd.JJvy
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detachedCriteria.getExecutableCriteria(session); !w;oVPNg
int totalCount = R0A|}Ee*
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((Integer) criteria.setProjection(Projections.rowCount }83a^E9L
"-T[D9(A
()).uniqueResult()).intValue(); G=ly .
criteria.setProjection (E{}iq@2
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(null); Z)^1~!w0
List items = l{o,"P"
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criteria.setFirstResult(startIndex).setMaxResults R9z:K_d,
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(pageSize).list(); 9Gc4mwu
PaginationSupport ps = sW^e D;
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new PaginationSupport(items, totalCount, pageSize, K8bKTG \
6|G&d>G$_
startIndex); <%iRa$i5
return ps; "\k|Z
} JuKG#F#,
}, true); |W#(+m
} 90[6PSXk
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public List findAllByCriteria(final H-&T)
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DetachedCriteria detachedCriteria){ n muzTFs=
return(List) getHibernateTemplate 2Wn*J[5
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().execute(new HibernateCallback(){ \]8F_K
publicObject doInHibernate v8} vk]b
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(Session session)throws HibernateException { VtN1 [}
Criteria criteria = Cvp!(<<gK
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detachedCriteria.getExecutableCriteria(session); 9?XQB%44
return criteria.list(); 4=~+Bz
} xt&4]M
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}, true); H[_i=X3-~
} ?:42jp3
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public int getCountByCriteria(final )! eJW(
;l %$-/%
DetachedCriteria detachedCriteria){ ?Gl]O3@3
Integer count = (Integer) "qrde4O
)GYnQoV4
getHibernateTemplate().execute(new HibernateCallback(){ @ tvz9N
publicObject doInHibernate g&*,j+$ }
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(Session session)throws HibernateException { = ;cTm5d;T
Criteria criteria = s(Bcw`'#
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detachedCriteria.getExecutableCriteria(session); uc>":V
return Uv m:`e~?
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criteria.setProjection(Projections.rowCount oo\7\b#Jx
@V&c=8)8
()).uniqueResult(); g\% Z+Dc
} ;,}Dh/&E
}, true); Z%Fc
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return count.intValue(); 5%%e$o+
} 4`B3Kt`o
} ZZn$N-
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用户在web层构造查询条件detachedCriteria,和可选的 ]h?q1
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 Bd]k]v+
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PaginationSupport的实例ps。 ;1HzY\d%<
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ps.getItems()得到已分页好的结果集 fX.1=BjXi
ps.getIndexes()得到分页索引的数组
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{
ps.getTotalCount()得到总结果数 Vu,e]@
ps.getStartIndex()当前分页索引 Y4C<4L?
ps.getNextIndex()下一页索引 0|Xz-Y
ps.getPreviousIndex()上一页索引 N=PSr 4
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 \h"U+Bv7
QC?~$>h!?
,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 w_f.\\1r
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一下代码重构了。 %vv`Vx2
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我把原本我的做法也提供出来供大家讨论吧: 8t3m$<7
<.mH-Y5i
首先,为了实现分页查询,我封装了一个Page类: 9Ta0Li
java代码: dU#-;/}o
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/*Created on 2005-4-14*/ O%3Hp.|!
package org.flyware.util.page; <PVwf`W.
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/** o@BV&|
* @author Joa !> =ybRe
* l n\qvD_
*/ b[GhI+_
publicclass Page { m<49<O6o
RC/45:hZZ
/** imply if the page has previous page */ (6.uNLr
privateboolean hasPrePage; ^?$,sS
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/** imply if the page has next page */ 9vz\R-un
privateboolean hasNextPage; 4-t^?T:qF
5f{P% x(
/** the number of every page */ :\vs kk),
privateint everyPage; |{&M#qXe
)S
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/** the total page number */ r\d(*q3B
privateint totalPage; 43pe6 ^.
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/** the number of current page */ @AF<Xp{
privateint currentPage; V^,eW!
gfs ;?vP
/** the begin index of the records by the current +U1
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a%e`
query */ hbOXR.0z
privateint beginIndex; Z4EmRa30 p
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/** The default constructor */ 4 sax
public Page(){ 'w27Lt'V
ni&|;"Nt-
} #]x3(}3W
VJ=>2'I
/** construct the page by everyPage Km;}xke6
* @param everyPage 00.x*v
* */ Jup)A`64
public Page(int everyPage){ dYwkP^KB
this.everyPage = everyPage; PR
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} &s='$a;4
UWF
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/** The whole constructor */ [Q0V 5P~Q'
public Page(boolean hasPrePage, boolean hasNextPage, v !8=B21
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8 ECX[fw
int everyPage, int totalPage, X3\PVsH$K
int currentPage, int beginIndex){ ly-(F2
this.hasPrePage = hasPrePage; W;'fAohr
this.hasNextPage = hasNextPage; E?G'F3i
this.everyPage = everyPage; J7* o%W*V
this.totalPage = totalPage; R7/S SuG6\
this.currentPage = currentPage; Xva(R<W7d<
this.beginIndex = beginIndex; Vw1>d+<~-)
} }! EVf
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/** jZ|M$I3*
* @return B=!!R]dxA
* Returns the beginIndex. K9lekevB
*/ ZQ]qJDk
publicint getBeginIndex(){ mUa#sTm
return beginIndex; 8u2k-_9
} hhze5_$_
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/** 4AS%^&ah
* @param beginIndex >UvP/rp
* The beginIndex to set. Jv8:GgSg
*/ ,7LfvZj4[
publicvoid setBeginIndex(int beginIndex){ B;r_[^
this.beginIndex = beginIndex; 3'Y-~^ml|
} ^Hv&{r77
px<psR5
/** M
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* @return =I`S7oF
* Returns the currentPage. orFwy!
*/ t,?,T~#9
publicint getCurrentPage(){ q<
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return currentPage; 1ysfpX{=
} 5c` ;~
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/** %):_
* @param currentPage cu N9RG
* The currentPage to set. Z*m^K%qJ
*/ YGJ!!(~r
publicvoid setCurrentPage(int currentPage){ hSm?Z!+
this.currentPage = currentPage; Hz.i $L0}
} ]SCHni_
^eh.Iml'@
/** 7GOBb|
* @return -G.N
* Returns the everyPage. 2g=
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*/ rGP;0KtQ
publicint getEveryPage(){ G*I
return everyPage; s<zN`&t
} V: D;?$Jl
"V' r}>
/** &DWSf`:Hx
* @param everyPage +]eG=.
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* The everyPage to set. M-nRhso
*/ i1cd9
publicvoid setEveryPage(int everyPage){ 0vqVE]C
this.everyPage = everyPage; Wx:v~/r
} I=kqkuW
O>' }q/
/** g8Ex$,\,
* @return .;4N:*hY
* Returns the hasNextPage. 9^XZ|`
*/ ^I!Z)/
publicboolean getHasNextPage(){ :}e<
return hasNextPage; O2Qmz=%
} MJ JC6:
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/** <[k3x8H'
* @param hasNextPage #c:s2EL
* The hasNextPage to set. ^3dc#5]Xf
*/ K1 "HJsj
publicvoid setHasNextPage(boolean hasNextPage){ yMN JHiE/
this.hasNextPage = hasNextPage; TRi'l #m4
} ,Vi_~b
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/** ]`$6=)_X
* @return IU8zidn&
* Returns the hasPrePage. :^]Po$fl
*/ $5i\D
rs
publicboolean getHasPrePage(){ ~^2w)-N
return hasPrePage; 6Cy Byj&
} 3N_KNW
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/** M2Nh3ijr
* @param hasPrePage f SkC>mWv
* The hasPrePage to set. h"1}j'2>@
*/ Fqeqn[,
publicvoid setHasPrePage(boolean hasPrePage){ }k VC]+
this.hasPrePage = hasPrePage; }dN\bb{#
} tx5bmF;b)
".>#Qp%
/** BQ6$T&
* @return Returns the totalPage. p6- //0qb
* gX{j$]^6G8
*/ Q#% LIkeq
publicint getTotalPage(){ SSI> +A
return totalPage; ^UvL1+
} c +]r
>)WE3PT/O"
/** u.2X"
* @param totalPage Yb5U^OjyJ
* The totalPage to set. e8`d<U
*/ fz|*Plv
publicvoid setTotalPage(int totalPage){ D9g*+KM&
this.totalPage = totalPage; `:iMGqZN
} (csk
sccLP_#Z
} gv eGBi
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aG7Lm2{c"
OAkqPG&w
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 ":eyf3M
I;XM4a
个PageUtil,负责对Page对象进行构造: XO;_F"H=
java代码: D\G 8p;
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/*Created on 2005-4-14*/ ;rf{T[i
package org.flyware.util.page; :7(fBf5
oT}$N_gFT
import org.apache.commons.logging.Log; d[h=<?E5
import org.apache.commons.logging.LogFactory; efyEzL
>(2;(TbQm0
/** q}_8iDO6
* @author Joa )P7oL.)
* \ ERBb.
*/ <\~@l^lU
publicclass PageUtil { +IXr4M&3
Ls2,+yo]>
privatestaticfinal Log logger = LogFactory.getLog ar@,SKU'K
~[!Tpq5
(PageUtil.class); MTwzL<@$
b|87=1^m[
/** _Q #[IH9
* Use the origin page to create a new page *fY*Wy9
* @param page eF;Jj>\R+i
* @param totalRecords # 9bw'm
* @return CM~x1f *v
*/ f:8!@,I
publicstatic Page createPage(Page page, int -qSGa;PJ
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totalRecords){ fbI5!i#lz
return createPage(page.getEveryPage(), iw.F8[})
"U9e)a0v
page.getCurrentPage(), totalRecords); ~e|E5[-i
} <YCjo[(~
GB+$ed5@<
/** 7IUJHc[R?
* the basic page utils not including exception [?6+ r
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handler Zq{gp1WC
* @param everyPage #}1yBxB<=
* @param currentPage `_D A!
* @param totalRecords UaG&HGg]!
* @return page MNh:NFCRA
*/ * k\;G?
publicstatic Page createPage(int everyPage, int bz:En'2>F
#x;d+Q@
currentPage, int totalRecords){ pvWNiW:~k
everyPage = getEveryPage(everyPage); -Nr*na^H9#
currentPage = getCurrentPage(currentPage); h 1'm[Y
int beginIndex = getBeginIndex(everyPage, 6ZjUC1
XcbEh
currentPage); J^WX^".E
int totalPage = getTotalPage(everyPage, \]FPv7!
af[dkuv
totalRecords);
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boolean hasNextPage = hasNextPage(currentPage, ./tZ*sP:
JrxQ.,*i
totalPage); ']!wc8m1"
boolean hasPrePage = hasPrePage(currentPage); [$6YPM>Ee
;Gp9
? 0
returnnew Page(hasPrePage, hasNextPage, }w=|"a|,
everyPage, totalPage, a'q&[08
currentPage, {h|kx/4{m
CT\rx>[J.6
beginIndex); s4Jy96<
} 8&hxU@T~
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privatestaticint getEveryPage(int everyPage){ njNqUo>
return everyPage == 0 ? 10 : everyPage; ra
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} jJ
RaY3
X&Ospl@H
privatestaticint getCurrentPage(int currentPage){ 6EY0Fjsi
return currentPage == 0 ? 1 : currentPage; nBd(pOe
} >TGc0 z+
)eX{a/Be
privatestaticint getBeginIndex(int everyPage, int t@2MEo
5HB*
currentPage){ 5rtE/{A
return(currentPage - 1) * everyPage; PTQN.[bBh
} =OrVaZ0
DLq'V.M:
privatestaticint getTotalPage(int everyPage, int +Lr`-</VF
Eg4&D4TGp
totalRecords){ Q*f0YjH!
int totalPage = 0; Rto/-I0l
xgsEe3|
if(totalRecords % everyPage == 0) ZlMS=<hgFx
totalPage = totalRecords / everyPage; 6m:$RW
else p`"Ic2xPJ
totalPage = totalRecords / everyPage + 1 ; uowdzJ7
x=W5e
^0?
return totalPage; 1Si$Q
} ;Rxc(tR!n
aMK\&yZD
privatestaticboolean hasPrePage(int currentPage){ z2A,*|I
return currentPage == 1 ? false : true; 9+Wf*:*EW
} Ln4Dq[M
f(EO|d^u
privatestaticboolean hasNextPage(int currentPage, 1#zD7b~
i\>?b)a>
int totalPage){ ^= kr`5
return currentPage == totalPage || totalPage == '~{kR=+
V_4=0(
0 ? false : true; MHCwjo"
} CQ{pv3)
/BS yanro
-|:mRAe
} Q}^qu6
I
'ha=PeVn
=+VDb5= TV
msq2/sS~
:@Ml-ZE
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。 JGYJ;j{E]
gP ^A
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 I!Fd~g9I4
2H1?f|0>
做法如下: `Gg,oCQg
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 5p7i9"tgn
KO))2GET
的信息,和一个结果集List: RRpCWcIv"
java代码: yx<-M
4^^=^c
jU{~3Gn?
/*Created on 2005-6-13*/ 94lz?-j
package com.adt.bo; R$2\Xl@qQF
i66/2BUh.
import java.util.List;
S O`b+B
AgOti]`aR
import org.flyware.util.page.Page; C)cuy7<
%YG[?"P'
/** _]< Tv3]RK
* @author Joa 1,n\Osd
*/ ] `;Fc8$
publicclass Result { OFZo"XtF
*b`1+~p_2
private Page page;
[1e/@eC5
5hDm[*83
private List content; bW GMgC
Rf!$n7& \
/** ,}^FV~
* The default constructor Rz<'&Z>;
*/ "!#KQ''R
public Result(){
yi<H }&
super(); Q*9Y.W. 8
} dFk$rr>q
#_'^oGz`
/** h\|T(597.
* The constructor using fields >4?735f=x
* 6"2IV
* @param page 8&y#LeM1TT
* @param content W#L/|K!S
*/ T9YrB
public Result(Page page, List content){ QOv@rP/
this.page = page; rL/H{.@$`
this.content = content; `Js"*[z
} xeRoif\4c
SM.KM_%K
/** P\$%p-G
* @return Returns the content. ?V =#x.9
*/ PSU}fo
publicList getContent(){ Bf$`Hf6
return content; wd2z=^S~
} B*}:YV
2GRv%:rZ
/** U ?6.UtNf
* @return Returns the page. 'On%p|s)H
*/ K#x|/b'5d
public Page getPage(){ WS\Ir-B
return page; S3y('
PeF
} eY`o=xN
Hw,@oOh.
/** l-8rCaq&J
* @param content :d|~k
* The content to set. 3
5p)e c
*/ R-Gg= l5
public void setContent(List content){ :;w#l"e7<
this.content = content; =DXN`]uN
} 4mm>6w8NT
ufocj1IU
/** 4V'HPD>=V
* @param page be
HEAQ
* The page to set. E_#?;l>
*/ rs0Wy
publicvoid setPage(Page page){ lB
this.page = page; RVh{wg
} Lwo9s)j<e
} YLb$/6gj6
Oh,]"(+
PeJIa
%iE
!WTL:dk
&&
b;Wr
2. 编写业务逻辑接口,并实现它(UserManager, xks Me
2k^'}7G%
UserManagerImpl) |Zdl[|kX
java代码: }qBmt>#
5I/lF oy7
yVyh\u\
/*Created on 2005-7-15*/ pL,l
package com.adt.service; yKC1h`2
1H8/b D
import net.sf.hibernate.HibernateException; [=^Wj`;
Yb%#\.M/y
import org.flyware.util.page.Page; vU9:`@beu
_>4)q=
import com.adt.bo.Result; U,Fyi6{~
^`bMFsP
/** c-ql
* @author Joa EvF[h:C2
*/ v4,Dt
publicinterface UserManager { *$@u`nM
A}(o1wuw
public Result listUser(Page page)throws H`rd bE
(btmg<WT"
HibernateException; H4<Q}([w
V+t's*9o3
} l\ VrD2j8
gzN51B =D
r'MA$PiS'
_Sl3)
&mm!UJ
java代码: 22 feYm|
\q^:$iY~
;?%_jB$P
/*Created on 2005-7-15*/ 4B)%I`
package com.adt.service.impl; #Sg"/Cc
Yh;A)Np
import java.util.List; R1(3c*0f
E@4/<;eKK
import net.sf.hibernate.HibernateException; .sD=k3d
M[(pLYq:
import org.flyware.util.page.Page; $CZ'[`+
import org.flyware.util.page.PageUtil; \r"gqv)^
TQ=HFs
~
import com.adt.bo.Result; ?/8V%PL~$
import com.adt.dao.UserDAO; w^NQLV S
import com.adt.exception.ObjectNotFoundException; ~7m+N)5
import com.adt.service.UserManager; "Cs36k
-,2CMS#N
/** -_XTy!I
* @author Joa /y(0GP4A
*/ q}W})
publicclass UserManagerImpl implements UserManager { HEw&'
~ 7<M6F
private UserDAO userDAO; I+
Y{_yw"f
BAtjYPX'w
/** %*#+(A"V
* @param userDAO The userDAO to set. <,\U,jU_
*/ YLuf2ja}X
publicvoid setUserDAO(UserDAO userDAO){ ',/2J0_
this.userDAO = userDAO; Y(R.<LtY
} $=) Pky-~
kT:I.,N
/* (non-Javadoc) nu(7YYCM$
* @see com.adt.service.UserManager#listUser o=Y'ns^a(
]J@-,FFC
(org.flyware.util.page.Page) W2'!Pc,W
*/ Fm*npK
public Result listUser(Page page)throws QNH3\<IS
z"Mk(d@-E
HibernateException, ObjectNotFoundException { m"QDc[^Ge
int totalRecords = userDAO.getUserCount(); <~uzKs0
if(totalRecords == 0) Q!_d6-*u
throw new ObjectNotFoundException (>NZYPw^3
aemi;61T\
("userNotExist"); +}PN+:yV
page = PageUtil.createPage(page, totalRecords); Je}0KW3G9L
List users = userDAO.getUserByPage(page); +wxsAGy_j
returnnew Result(page, users); c94=>p6
} p}<60O"r$
o4wSt6gBcJ
} jcb&h@T8kv
|gIE$rt-~W
fH$#vRcq
O8SE)R~
_
j`tR:
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 SZ}=~yoD(
v*%52_
询,接下来编写UserDAO的代码: ESYF4-d+
3. UserDAO 和 UserDAOImpl: V@[C=K
java代码: {Wu[e,p
]qxl^Himq
2t
PfIg
/*Created on 2005-7-15*/ {Ay dt8
package com.adt.dao; %D5F7wB
e[s}tjx
import java.util.List; _54gqD2C,
}
!y5hv!_
import org.flyware.util.page.Page; LD1&8kJ*l
cnI5G!
import net.sf.hibernate.HibernateException; @bJIN]R
^39lUKL
/** v; R2,`[W
* @author Joa xiDgQTDz
*/ AV7#,+p%G
publicinterface UserDAO extends BaseDAO { cqSXX++CS,
_{-[1-lN5_
publicList getUserByName(String name)throws dDIR~!T
}}i'8
HibernateException; G]4Ca5;Z!N
m(*rMO>_
publicint getUserCount()throws HibernateException; n,2
=^i K^)
publicList getUserByPage(Page page)throws mEsb_3?#+
D:f=Z?L)>
HibernateException; |`t 6lVO,Z
X%3?sH
} H!&_Tv[
uYWD.]X;[
(zsv!U
F"UI=7:o
O9p s?{g
java代码: 40pz <-B
D>-r `
"RN]
@p#m
/*Created on 2005-7-15*/ 8-Y*b89
package com.adt.dao.impl; L!lmy&1
P_w4
DU
import java.util.List; &JcatI
-5 D<zP/
import org.flyware.util.page.Page; "ayV8{m^3
V~ORb1
import net.sf.hibernate.HibernateException; mfN'+`r
import net.sf.hibernate.Query; 5af0- hj
brs`R#e \
import com.adt.dao.UserDAO; IEMa/[n/
-v.\W y~\
/** &i(Ip'r
* @author Joa 5l
3PAG
*/ ]B?M3`'>
public class UserDAOImpl extends BaseDAOHibernateImpl Hd\V?#H
.<F46?HS
implements UserDAO { `SsoRPW&$
)Wr_*>xj
/* (non-Javadoc) 0hV#]`9`gN
* @see com.adt.dao.UserDAO#getUserByName Z|%h-~
_X~O6e-!
(java.lang.String) (8)9S6
*/ 4&sf{tI
publicList getUserByName(String name)throws ?'z/S5&j
CV.|~K0O
HibernateException { &h5Y_no GX
String querySentence = "FROM user in class Xt<1b
lz~^*\ F
com.adt.po.User WHERE user.name=:name"; %DYh<U4N
Query query = getSession().createQuery "(7y%TFt:
A*?PH`bY
(querySentence); d\l{tmte
query.setParameter("name", name); Syy{ ^Ae}
return query.list(); rZJJ\ , |
} e,/]]E/o
ZK+F<}
/* (non-Javadoc) jDpA>{O[
* @see com.adt.dao.UserDAO#getUserCount() uC^)#Y\"
*/ \&hq$
publicint getUserCount()throws HibernateException { z3K$gEve
int count = 0; dAx
? ,
String querySentence = "SELECT count(*) FROM ]690ey$E:j
(.cA'f?h
user in class com.adt.po.User"; HS/.H,X
Query query = getSession().createQuery .Y;f9R
_ZK^JS
(querySentence); N*}soMPV^.
count = ((Integer)query.iterate().next JM|HnyI
jJ$B^Y"4
()).intValue(); !SW0iq[7j
return count; QQ .?A(U7
} \ +%~7Bi]z
~p?ArZb
/* (non-Javadoc) Wvf>5g)?
* @see com.adt.dao.UserDAO#getUserByPage gZ$
8Y7
~3?-l/ $
(org.flyware.util.page.Page) 5 ix*wu`,
*/ !q\=e@j-i
publicList getUserByPage(Page page)throws S
F*C'
p{^:b6
HibernateException { 4 k<o
String querySentence = "FROM user in class @)6b
^EX"fRwNi
com.adt.po.User"; cZNcplt8
Query query = getSession().createQuery S>~f.
,r w4Lo
(querySentence); /B@{w-N
query.setFirstResult(page.getBeginIndex()) a31e.36g
.setMaxResults(page.getEveryPage()); !Ud'(iGa
return query.list(); |VWT4*K
} m6ge
%
w5HIR/kP
} = 'o3 <}
0w3c8s.
FfJ;r'eGs
MF4(
Q:(mK* _
至此,一个完整的分页程序完成。前台的只需要调用 W/!P1M n
djOjd,
userManager.listUser(page)即可得到一个Page对象和结果集对象 3y}E*QE
CW
&z?B ra
的综合体,而传入的参数page对象则可以由前台传入,如果用 #y:D{%Wp
g8##Be
webwork,甚至可以直接在配置文件中指定。 c a_mift
"CJ~BJI%
下面给出一个webwork调用示例: _Hv+2E[4Z
java代码: PR.3EL
4=([v;fc
Q%JI-&K
/*Created on 2005-6-17*/ ~Kw#^.$3T
package com.adt.action.user; ~V8z%s@
#{q.s[g*+1
import java.util.List; d2`g,~d
P"_/P8
import org.apache.commons.logging.Log; XGx[Ny_A2
import org.apache.commons.logging.LogFactory; *vD.\e~
import org.flyware.util.page.Page; \FVfV`x
Qu61$!
import com.adt.bo.Result; nnv|GnQST
import com.adt.service.UserService; q*3OWr
import com.opensymphony.xwork.Action; \~
D(ww
d&j
/** ukSv70Ev
* @author Joa Jp=fLo 9
*/ xQu|D>kv87
publicclass ListUser implementsAction{ JI5o~;}m
t@qf/1
privatestaticfinal Log logger = LogFactory.getLog 9=>fx
LORcf 1X/
(ListUser.class); ,2S!$M
]c/E7|0Q
private UserService userService; 2FIL@f|\7z
y/Xs+ {x
private Page page; al9wNtMT
Q1,sjLO-a
privateList users; YExgUE|
I%3[aBz4
/* U N9hZ>9
* (non-Javadoc) 7)lEZJK&T
* 32YbBGDN!f
* @see com.opensymphony.xwork.Action#execute() dz_S6o ]
*/ R*[sO*h\k
publicString execute()throwsException{ =fcg4h5(
Result result = userService.listUser(page); KxkBP/`3Q
page = result.getPage(); yq%5h[M
users = result.getContent(); u.GnXuax
return SUCCESS; 1r;zA<<%R
} *&NP?-E
Xqf,_I=V
/** |THpkfW
* @return Returns the page. :o'x?]
*/ o!M8V ^vW
public Page getPage(){ 4Z)s8sD KW
return page; ~bLx2=-"
} \R#SoOd
za_b jE
/** = s&Rk~2b/
* @return Returns the users. xa~]t<2
*/ +hyOc|5
publicList getUsers(){ ^m qEKy<
return users; JusU5 e|
} EwP2,$;
'UX.Q7W
/** OIcXelS:@k
* @param page <3;p>4gN
* The page to set. n Nt28n@
*/
~non_pJ
publicvoid setPage(Page page){ ^D+J
k8
this.page = page; dHnCSOM<
} I!sT=w8V
&$MC!iMh
/** n>Ff tVZNJ
* @param users s<O$
Y
* The users to set. ~aob@(
*/ 8SGaS&
publicvoid setUsers(List users){ G|wtl(}3
this.users = users; 2cMCZuO
} r_T)|||v
R/vHq36d
/** RzEzNV
* @param userService b#VtPn]
* The userService to set. 3!CUJs/W
*/
I1Q!3P
publicvoid setUserService(UserService userService){ GcBqe=/B!
this.userService = userService; Yuvi{ 0
} ]5ZXgz
} ,d#*i
8u[_t.y4m
WK{`_c
U^
51|ky-
~>u.d
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, cQU/z"?+
EeuYRyK
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 EQ1**[$
] ,|,/~
么只需要: QaWS%0go
java代码: 1JJsYX
owAO&"C
}p)K6!J0
<?xml version="1.0"?> @oXGa>Ru
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork D-gH_ff<]9
vSgT36ZF
1.0//EN" "http://www.opensymphony.com/xwork/xwork- rAenxZ,tF
mWp>E`l
1.0.dtd"> zggnDkC5
J@3,
<xwork> GY~$<^AK
zx.qN
<package name="user" extends="webwork- {EgSjxfmw
U+S=MP
}:
interceptors"> n]4E>/\
Uj!3MF
<!-- The default interceptor stack name o@:"3s
- x
--> $RD~,<oEm
<default-interceptor-ref ?cV,lak
/$~1e7W
name="myDefaultWebStack"/> <FT7QO$I
yJA~4
<action name="listUser" +}:Z9AAMy
S$mv(C
class="com.adt.action.user.ListUser"> !=[Y yh
<param q}{E![ZTu
) c@gRb~
name="page.everyPage">10</param> tLE8+[
SU
<result ;4F6
$T'I
R/hf"E1
name="success">/user/user_list.jsp</result> r4yz{^G
</action> eM7@!CdA9q
f|d~=\0y
</package> \""^'pP@
Bx?3E^!T
</xwork> @v-^j
}[p{%:tP
_7c3=f83
s(,S~
=ZgueUz,
iE%" Q? Q/
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 x YS81
~A0]vcP
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 :'%6
'Y?-."eKh
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 X=)V<2WO
bLc5$U$!I
CoN[Yf3\
Al$z.i?R
oi #B7
我写的一个用于分页的类,用了泛型了,hoho wuqe{?
(NJ{>@&
java代码: LlTD =tJ0
EGu%;[
BA;r%?MRL
package com.intokr.util; M8},RR@{
)GP;KUVae
import java.util.List; T.bFB+'E|
J
En jc/
/** %cF`x_h[j
* 用于分页的类<br> .D*Qu}
* 可以用于传递查询的结果也可以用于传送查询的参数<br> -^p{J
TB+
* DE(XSzX
* @version 0.01 ]*0zir/
* @author cheng [|nK5(e9
*/ E7uIur=g!
public class Paginator<E> { ]c(FgYc
privateint count = 0; // 总记录数 +R'8$
privateint p = 1; // 页编号 PRhC1#
privateint num = 20; // 每页的记录数 aV;|2}q "
privateList<E> results = null; // 结果 sY]J!"
2yN!yIPR
/** 15:9JVH3D
* 结果总数 66=[6U9 *
*/ %4~"$kE
publicint getCount(){ Jqoo&T")
return count; Yh<F-WOo2
} -E-#@s
N_Us6X
publicvoid setCount(int count){ G]lGoa}]`u
this.count = count; w2LnY1A
} osp~)icun
:jiEn
y
/** Fis!MMh.$
* 本结果所在的页码,从1开始 Ycr3$n]e
* VU3RFl
* @return Returns the pageNo. ~&?([}A
*/ \@Wv{0a(
publicint getP(){ +t!]nE#
return p; zIa={tU
} [&TF]az
Qz(D1>5I?
/** )*KMU?
* if(p<=0) p=1 j0l,1=^>l
* 1?'4%>kp
* @param p (UkP AE
*/ pqG>|#RG
publicvoid setP(int p){ x@#>l8k?
if(p <= 0) ?2@^O=I
p = 1; jWdviS9&g
this.p = p; ] \yIHdcDi
} Ib(C`4%
is;g`m
/** ?:R ]p2 ID
* 每页记录数量 6h9(u7(-N
*/ ]E9iaq6Z
publicint getNum(){ |MNSIb&,W
return num; rto?*^N?
} HUKrp*Hv
aCZ0-X?c
/** `>"#d
?,
* if(num<1) num=1 V^7.@BeT
*/ PT>b%7Of
publicvoid setNum(int num){ @A[)\E1
if(num < 1) *@rA7zPFf
num = 1; ]d*9@+Iu
this.num = num; oW~W(h!
}
Zkp~qx
F^l1WX6
/** gT}H B.
* 获得总页数 1AJ6NBC&c
*/ Vgm*5a6t
publicint getPageNum(){ XIcUoKg^
return(count - 1) / num + 1; ^".OMS"!
} (\:Rnl
zs=3e~o3
/** 'sEnh<
* 获得本页的开始编号,为 (p-1)*num+1 * +
T(i
*/ b9H(w%7ucU
publicint getStart(){ :82T!
return(p - 1) * num + 1; #:6-O
} 7Ae`>5B#
X,Ql6uO
/** x`6MAZ
* @return Returns the results. p?gm=b#
*/ L;V8c
publicList<E> getResults(){ I%d=c0>%
return results; -y.cy'$f
} >LBA0ynh
{
e-dkvPr
public void setResults(List<E> results){ a_N7X
this.results = results; Us`=^\
} _H$Lu4b)N
hjL;B'IL
public String toString(){ hBU)gP75
StringBuilder buff = new StringBuilder w =GMQ8
'z}
t= ?
(); 0U=wGIO
buff.append("{"); $N?8[
buff.append("count:").append(count); /k'7j*t Z
buff.append(",p:").append(p); )+
<w>pc
buff.append(",nump:").append(num); ztVTXI%Kz
buff.append(",results:").append 5=o ^/Vkc
2@S}x@^
(results); (Yewd/T
buff.append("}"); }UyQGRZ=
return buff.toString(); ZthT('"a
} JBY.er`6C
Nh\vWAz9
} 'rhgM/I
:FAPH8]
\HGf!zZ