Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 fZ6 fV=HEF
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 \>Ga-gv6/
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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 ovDJ{3L6O
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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 2 ]V>J
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分页支持类: 0;FqX*
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java代码: q[)q|R|
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package com.javaeye.common.util; Q&Z4r9+Z
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import java.util.List; so!w !O@@
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publicclass PaginationSupport { ]> )u+|
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publicfinalstaticint PAGESIZE = 30; JQ"`9RNb
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privateint pageSize = PAGESIZE; ePq13!FC/
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privateList items; MegE--h
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privateint totalCount; \LdmGv@&
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privateint[] indexes = newint[0]; |*tWF!
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privateint startIndex = 0; $hjP}- oUX
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public PaginationSupport(List items, int 'dIX=/RZ
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totalCount){ >d8x<|D
setPageSize(PAGESIZE); b^[W_y
setTotalCount(totalCount); G$;]
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setItems(items); M5GY>3P$c
setStartIndex(0); t."g\;
} #`jE%ONC
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public PaginationSupport(List items, int
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-?< Ww{
totalCount, int startIndex){ hWD !
setPageSize(PAGESIZE); 1R=)17'O
setTotalCount(totalCount); U1,~bO9
setItems(items); 0?lp/|K
setStartIndex(startIndex); m~)Fr8Wh6
} bZNIxkc[Dh
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public PaginationSupport(List items, int f^W[;w
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totalCount, int pageSize, int startIndex){ jM5_8nS&d
setPageSize(pageSize); E rop9T1
setTotalCount(totalCount); @br@[RpB
setItems(items); }P<Qz^sr_
setStartIndex(startIndex); Y{B9`Z
} g.64Id
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publicList getItems(){ "?apgx 6
return items; j5L)N
} T4OguP=
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publicvoid setItems(List items){ ([:]T$0 #
this.items = items; t"<s} ~
} I
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publicint getPageSize(){ J=I:T2bV&s
return pageSize; ic%?uWN
} .6> hD1'
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publicvoid setPageSize(int pageSize){ XB0a dp
this.pageSize = pageSize; &|v{#,ymeb
} h ?uqLsRl
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publicint getTotalCount(){ 5Z/yhF.{
return totalCount; duX0Mc.0P
} M]}l^m>L
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publicvoid setTotalCount(int totalCount){ ;mEwQ
if(totalCount > 0){ cVO,~I\\
this.totalCount = totalCount; :w@F?:C
int count = totalCount / 81~Kpx
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pageSize; v#
if(totalCount % pageSize > 0)
}10\K
count++; ,Pn-ZF
indexes = newint[count]; (2UW_l
for(int i = 0; i < count; i++){ 4L8z>9D
indexes = pageSize *
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i; EQ4#fAM)
} 'eDJ@4Xm
}else{ \[:PykS
this.totalCount = 0; ac9qj
} v @:~mwy
} 94\t1fE
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publicint[] getIndexes(){ pX@Si3G`
return indexes; g %f*ofb
} &J_Z~^
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publicvoid setIndexes(int[] indexes){ 7 _`L$<-n
this.indexes = indexes; J , V
} Rj^7#,993
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publicint getStartIndex(){ :z]}ZZ
return startIndex; ?AEd(_a!q
} -;^;2#](g
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publicvoid setStartIndex(int startIndex){ OB(pIzSe
if(totalCount <= 0) + :V rip
this.startIndex = 0; /D<"wF }@J
elseif(startIndex >= totalCount) OA[&Za#w
this.startIndex = indexes P}0*{%jB
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[indexes.length - 1]; O`WIkBV!
elseif(startIndex < 0) >&OUGu|
this.startIndex = 0; :-?Ct
else{ Z,K7Ot0
this.startIndex = indexes qz 9tr
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[startIndex / pageSize]; wJgX/W
} n-$VUo
} -D^L}b
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publicint getNextIndex(){ ` @8`qXg
int nextIndex = getStartIndex() + $$hv`HE^l
Ur^j$B}
pageSize; hrbo:8SL
if(nextIndex >= totalCount) Ow3P-UzU3
return getStartIndex(); UfO7+_2
else <\" .L
return nextIndex; (zG.aaz*C
} SVagT'BB
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publicint getPreviousIndex(){ . V$ps-t
int previousIndex = getStartIndex() - _d@=nK)
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pageSize; ZQ3_y $
if(previousIndex < 0) %r;w;`/hA
return0; {^5?)/<
else G/vC~6x
return previousIndex; K^zDNIQU
} 6 "U8V?E
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} (DDyK[t+VX
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抽象业务类 `Gd$:qV
java代码: !g>.i`
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/** Sw8kIC
* Created on 2005-7-12 WA$JI@g
*/ w\w(U
package com.javaeye.common.business; aE|OTm+@9;
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import java.io.Serializable; [BM*oEFPB*
import java.util.List; "CQw/qZw
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import org.hibernate.Criteria; -h#mn2U~3r
import org.hibernate.HibernateException; W2Luz;(U
import org.hibernate.Session; ; |L<:x/
import org.hibernate.criterion.DetachedCriteria; {_#y z\j
import org.hibernate.criterion.Projections; hXn3,3f3oZ
import YE}s
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org.springframework.orm.hibernate3.HibernateCallback; TZRcd~ 5$
import U7iuY~L
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org.springframework.orm.hibernate3.support.HibernateDaoS pFsc}R/0/8
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upport; (*\jbK
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import com.javaeye.common.util.PaginationSupport; k~3.MU
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public abstract class AbstractManager extends hWo=;#B*
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HibernateDaoSupport { LfLFu9#:w
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privateboolean cacheQueries = false; }fR,5|~X
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privateString queryCacheRegion; #~L h#
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publicvoid setCacheQueries(boolean 4~z?"
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cacheQueries){ PX(pX>
this.cacheQueries = cacheQueries; 8|Y.|\
} "YU{Fkl#j
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publicvoid setQueryCacheRegion(String &o3K%M;C?
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queryCacheRegion){ N#C1-*[C
this.queryCacheRegion = Q@@v1G\
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queryCacheRegion; sJ
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} wJ<Oo@snm
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publicvoid save(finalObject entity){ l8h&|RY[
getHibernateTemplate().save(entity); sZ<9A Xk-E
} CjIu[S1%
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publicvoid persist(finalObject entity){ `Y=WMNy
getHibernateTemplate().save(entity); MZJ]Dwt]
} &w8)* T
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publicvoid update(finalObject entity){ 'R<&d}@P*#
getHibernateTemplate().update(entity); f:B>zp;N
} ;Lm=dd@S:
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publicvoid delete(finalObject entity){ X^9d/}uTa
getHibernateTemplate().delete(entity); k
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} ;a{ :%t
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publicObject load(finalClass entity, wd(Hv
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finalSerializable id){ P^`duZ{T
return getHibernateTemplate().load -u!FOD/
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(entity, id); 2lKV#9"
} ?E%ELs_Dl
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publicObject get(finalClass entity, P +"Y
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finalSerializable id){ l1U=f]
return getHibernateTemplate().get JO<wK
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(entity, id); wkqX^i7ls
} Cv
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publicList findAll(finalClass entity){ )}vNOE?X~
return getHibernateTemplate().find("from ps
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" + entity.getName()); oh"O07
} 65h @}9,U
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publicList findByNamedQuery(finalString `U#55k9^5
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namedQuery){ r;L>.wl*I
return getHibernateTemplate +YLejjQ
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().findByNamedQuery(namedQuery); ,lA.C%4au~
} P}ok*{"J<>
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publicList findByNamedQuery(finalString query, V7G7&'
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finalObject parameter){ DrnJ;Hi"
return getHibernateTemplate ;,i]w"*
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().findByNamedQuery(query, parameter); ~8"8w(CG*I
} ay "'#[
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publicList findByNamedQuery(finalString query, R8rfM?"W
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finalObject[] parameters){ jdE5~a+
return getHibernateTemplate -C(b,F%%
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().findByNamedQuery(query, parameters); #ET/ =
} LK6; ?m
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publicList find(finalString query){ 8Og_W8
return getHibernateTemplate().find %AOja+
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(query); 322jR4QGr
} E9?phD
?(*t@
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publicList find(finalString query, finalObject E*L iM5+I
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parameter){ 5JEbe
return getHibernateTemplate().find DvvT?K
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(query, parameter); :l|%17N
} HV6f@
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public PaginationSupport findPageByCriteria S=_vv)6+4
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(final DetachedCriteria detachedCriteria){ \U|ZR
return findPageByCriteria 3}|'0(hYL
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c
(detachedCriteria, PaginationSupport.PAGESIZE, 0); dl hdsj:
} >^XBa*4;Y
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public PaginationSupport findPageByCriteria N3u((y/
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(final DetachedCriteria detachedCriteria, finalint PJ cwH6m
G$ _yy:
startIndex){ DjSbyXvrg
return findPageByCriteria Gmf B
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(detachedCriteria, PaginationSupport.PAGESIZE, ~ek$C
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startIndex); +}f9
} LM&y@"wfm
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public PaginationSupport findPageByCriteria ?c0xRO%y
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(final DetachedCriteria detachedCriteria, finalint JK.ZdY%
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pageSize, Oft4-4$E
finalint startIndex){ l}$ U])an#
return(PaginationSupport) "M|zv
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getHibernateTemplate().execute(new HibernateCallback(){
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publicObject doInHibernate >yY'7Ey
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(Session session)throws HibernateException { [HCAmnb
Criteria criteria = detwa}h[0
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detachedCriteria.getExecutableCriteria(session);
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int totalCount = KiJT!moB
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((Integer) criteria.setProjection(Projections.rowCount 4lBU#V7
SPp#f~%m
()).uniqueResult()).intValue(); r\AyN=
y
criteria.setProjection ID#I`}h.k
765p/**
(null); Mi]L]-L
List items = 1KjU ]
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criteria.setFirstResult(startIndex).setMaxResults hAHq\
+[5.WC7J
(pageSize).list(); I4&::y^C
PaginationSupport ps = qIld;v8w"g
-WYAN:s
new PaginationSupport(items, totalCount, pageSize, !qX_I db\
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startIndex); ;]_o4e6\p
return ps; ?. D3'qv
} 6ND`l5
}, true); 2 !'A:;
} 4C FB"?n0
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public List findAllByCriteria(final AE} )o)B
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DetachedCriteria detachedCriteria){ EY \H=@A
return(List) getHibernateTemplate ;\p KDPr
%'[&U# -
().execute(new HibernateCallback(){ 1 5A*7|
publicObject doInHibernate _Gu-
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(Session session)throws HibernateException { g55`A`5%C
Criteria criteria = h[PYP5{L
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detachedCriteria.getExecutableCriteria(session); /{|fyKo\?
return criteria.list(); P3oI2\)*i
} R+Y4|
}, true); e*L.U~ZR
} up'Tit
);FJx~b
public int getCountByCriteria(final vsa92c@T
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DetachedCriteria detachedCriteria){ Ek6MYc8<b~
Integer count = (Integer) 9]e V?yoA8
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getHibernateTemplate().execute(new HibernateCallback(){ 48Mpf=f`
publicObject doInHibernate VO"("7L
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(Session session)throws HibernateException { mW:!M!kk
Criteria criteria = 3"O>&Q0c
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detachedCriteria.getExecutableCriteria(session); &8z[`JW,T
return hEw-
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criteria.setProjection(Projections.rowCount *W
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f"St&q>[s
()).uniqueResult(); O)"gS!,
} 9D4NX<_
}, true); J&T.(
return count.intValue(); '{(UW.Awo
} 0pbtH8~
} ;6!Pwb;hY
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用户在web层构造查询条件detachedCriteria,和可选的 `P9XqWr
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 6qp%$>$Vt;
7P9=)$(EH
PaginationSupport的实例ps。 1Uqu>'
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ps.getItems()得到已分页好的结果集 PK"c4>q
ps.getIndexes()得到分页索引的数组 w08?DD]CDt
ps.getTotalCount()得到总结果数 C[%OkPR,H
ps.getStartIndex()当前分页索引
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ps.getNextIndex()下一页索引 #H0dZ.$b0
ps.getPreviousIndex()上一页索引 65Cg]Dt71
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 &cu lbcz
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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 -UD\;D?$
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一下代码重构了。 ;
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我把原本我的做法也提供出来供大家讨论吧: q5#J~n8Wr
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首先,为了实现分页查询,我封装了一个Page类: .<Zy|1
4
java代码: c.j$9=XLBG
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/*Created on 2005-4-14*/ >>5NX"{
package org.flyware.util.page; ;W^o@*i{>
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/** B|&"#Q
* @author Joa ph-ATJ"
* /;utcc
*/ a(0*um(
publicclass Page { @0SC"CqM
v_nj$1dY6
/** imply if the page has previous page */ V7Mh-]
privateboolean hasPrePage; iySRY^
>mjNmh7
/** imply if the page has next page */ YxP@!U9dE,
privateboolean hasNextPage; G 8V,
Bn(W"=1
/** the number of every page */ H V;D?^F
privateint everyPage; qIAoA.
gwWN%Z"
/** the total page number */ >b]S3[Q(
privateint totalPage; t>[KVVg
W
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/** the number of current page */ /\WQxe
privateint currentPage; <0PT"ij
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/** the begin index of the records by the current r9ww.PpNk#
yn/rW$
query */ %,k][V
privateint beginIndex; ^)W[l!!<)
()3O=!
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/** The default constructor */ z~>pVs
public Page(){ |K|h+fgG6*
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}
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cJL'$`gWf
/** construct the page by everyPage 4`8<
* @param everyPage r!{LLc}>
* */ ](^(=%
public Page(int everyPage){ Ix(><#P
this.everyPage = everyPage; 6O}`i>/6M
} J|w)&bV
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/** The whole constructor */ {Pc<u
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public Page(boolean hasPrePage, boolean hasNextPage, 44F`$.v96
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int everyPage, int totalPage, V@\%)J'g
int currentPage, int beginIndex){ @`,1:
this.hasPrePage = hasPrePage; -%I2[)F<
this.hasNextPage = hasNextPage; B0ndcB-
this.everyPage = everyPage; QQV~?iW{~
this.totalPage = totalPage; izx#3u$P
this.currentPage = currentPage; 37RLE1Yf
this.beginIndex = beginIndex; &CG*)bE
} HuVJ\%.
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/** QurW/a
* @return ZPD[5)~
* Returns the beginIndex. Cj?L@%"
*/ RJ$7XCY%`*
publicint getBeginIndex(){ FSRj4e1y1
return beginIndex; Kk{<@v)
} uSR~@Lj ~
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/** NmSo4Dg`U
* @param beginIndex }nMPSerE
* The beginIndex to set. ,DZX$Ug~+E
*/ leQT-l2Bk
publicvoid setBeginIndex(int beginIndex){ 59Gk3frk(
this.beginIndex = beginIndex; q]\g,a
} d`(@_czdF
=lu/9
i6
/** @_LN3zP
* @return g=e71DXG2
* Returns the currentPage. <Engi!
*/ tu5*Qp\
publicint getCurrentPage(){ H~E(JLcU
return currentPage; 1Zi,b
} nw6+.pOy
shMSN]S_x
/** A<B=f<N3gV
* @param currentPage 7k( Kq5w.
* The currentPage to set. t&(PN%icD
*/ fhCc! \
publicvoid setCurrentPage(int currentPage){ KW7UUXL
this.currentPage = currentPage; +/ &_v^sC;
} "$}vP<SM
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/** 1\r|g2Z
:
* @return 9Fr3pRIJ
* Returns the everyPage. po}F6m8bX
*/ 6AWKLFMV
publicint getEveryPage(){ {N#KkYH{"
return everyPage; DSj(]U~r
} UYz0PSV=.
8dlw-Q'S
/** @e'5E^
* @param everyPage RAp=s
* The everyPage to set. /P
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*/ )<xypDQ
publicvoid setEveryPage(int everyPage){ &< !Ufa&
this.everyPage = everyPage; M5trNSL&u
} Tdc3_<1
^7.h%lSg
/** \fjMc }'
* @return dqX;#H}h
* Returns the hasNextPage. X~xd/M=9^
*/ Jx=hJ-FY
publicboolean getHasNextPage(){ 2mq$H_
return hasNextPage; A Z{^o4<q
} #"49fMi/
raQ7.7
/** E{2Eoj;gq
* @param hasNextPage +GAf O0
* The hasNextPage to set. "rAY.E]
*/ oY=q4D
publicvoid setHasNextPage(boolean hasNextPage){ s<]&*e&}?
this.hasNextPage = hasNextPage; -uH#VP{0M
} 8x[YZ@iM-
/NFz4h=>
/** bTSL<"(]N
* @return =GXu 5 8
* Returns the hasPrePage. aIXdV2QS
*/ )$Z=t-q
publicboolean getHasPrePage(){ sk|=% }y
return hasPrePage; | 0,vQv
} dCFlM&(i
ZY56\qcY
/** d;+[i
* @param hasPrePage Zx$ol;Yd
* The hasPrePage to set. W#Qmv^StZ
*/ _aPh(qprc
publicvoid setHasPrePage(boolean hasPrePage){ ]0r|_)s
this.hasPrePage = hasPrePage; cGwf!hA
} p)~lL
Tb1U^E:
/** wap3Kd>MP
* @return Returns the totalPage. _e7-zg$/
* [qoXMuC|P
*/ dgo3'ZO
publicint getTotalPage(){ 2:LHy[{5
return totalPage; O0PJ6:9P
} m5D"A D
9Ok9bC'?8@
/** J4YBqp
* @param totalPage :ZDMNhUl
&
* The totalPage to set. 178Mb\8
*/ 9RwawTM
publicvoid setTotalPage(int totalPage){ !SKV!xH9
this.totalPage = totalPage; nPUqMn'
} k'X;ruQ:tF
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} dz[
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1w"8~Z:UXV
g`>og^7g
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 pZZf[p^s|
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个PageUtil,负责对Page对象进行构造: .O0O-VD+a
java代码: 9GdB#k6W`
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/*Created on 2005-4-14*/ RB?V7 uX
package org.flyware.util.page; T%R:NQf
yE} dj)wd
import org.apache.commons.logging.Log; 5yVkb*8HS
import org.apache.commons.logging.LogFactory; V|>oGtt7
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/** B[9 (FRX
* @author Joa PNeh#PI6)
* 0W^dhYO
*/ {k(eNr,
publicclass PageUtil { ;
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S.|FL%;
privatestaticfinal Log logger = LogFactory.getLog drq hQ
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(PageUtil.class); \/|)HElKR
*Ul*%!?D
/** 19q{6X`x
* Use the origin page to create a new page @InZ<AW>|
* @param page !SsHAE|
* @param totalRecords OU7 %V)X5
* @return y }08~L?2
*/ &2I*0
publicstatic Page createPage(Page page, int _KD5T4FZR
+2C?9:bH
totalRecords){ q|)Q9+6$+
return createPage(page.getEveryPage(), ]+H?@*b`
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page.getCurrentPage(), totalRecords); /( 6|{B
} K^t?gt@k}
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/** <f~Fl^^8
* the basic page utils not including exception Bf4%G,o5
a1N!mQ^
handler Wd(86idnc
* @param everyPage }vt%R.u
* @param currentPage v0l_w
* @param totalRecords $WW)bP
d4^
* @return page D';eTy Y
*/ k6\^p;!Y
publicstatic Page createPage(int everyPage, int C+NF9N
{w^uWR4f
currentPage, int totalRecords){ jQj,q{eA
everyPage = getEveryPage(everyPage); E&~nps8e
currentPage = getCurrentPage(currentPage); giavJ|
int beginIndex = getBeginIndex(everyPage, 7 boJ*
kVDe6},D7
currentPage); G.U5)4_^
int totalPage = getTotalPage(everyPage, 4-v6=gz.
5 ZfP
totalRecords); Me:{{-V4
boolean hasNextPage = hasNextPage(currentPage, ?PPZp6A3L=
v@EQ^C2.&
totalPage); yy(A(}
boolean hasPrePage = hasPrePage(currentPage); bb=uF1
F#+ .>!
returnnew Page(hasPrePage, hasNextPage, Ey&aBYR
everyPage, totalPage, HT`1E0G8)
currentPage, }{],GHCjQ
G\iyJSj[P
beginIndex); G{
mC7@
} v
vE\
`3iQZui
privatestaticint getEveryPage(int everyPage){ 1x >iz
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return everyPage == 0 ? 10 : everyPage; KhM.Tc
} rlznwfr7+
QYThW7S
privatestaticint getCurrentPage(int currentPage){ ~S(^T9R
return currentPage == 0 ? 1 : currentPage; mgkyC5)d
} pvXcLR)L+3
^i_Iqph=
privatestaticint getBeginIndex(int everyPage, int {8NwFN.
eXy"^xp^
currentPage){ hRTMFgO
return(currentPage - 1) * everyPage; PCfo
} =K$,E4*
F;D1F+S
privatestaticint getTotalPage(int everyPage, int Nf?\AK!
,-rB=|w
totalRecords){ ]HvZ$
int totalPage = 0; [6gO
h{]#ag5`
if(totalRecords % everyPage == 0) G?V"SU.
totalPage = totalRecords / everyPage; RIhOR8)
else Q;26V4
totalPage = totalRecords / everyPage + 1 ; E`@43Nz
V_a)jJ
return totalPage; .RRlUWu
} [!?wyv3
T{S4|G1R6
privatestaticboolean hasPrePage(int currentPage){ QB 77:E
return currentPage == 1 ? false : true; m)f|:MM
} ?y-s20Kd
A0#Y, 1
privatestaticboolean hasNextPage(int currentPage, yr4ou
MEU[%hty_
int totalPage){ J_ V,XO
return currentPage == totalPage || totalPage == kX8=cL9G
l_+A5Xy
0 ? false : true; G :4;y7
} &(O06QL
Q\#UWsN(T/
`fW{yb
} _+zVpZ
1!/-)1t
If.n(t[M9
|%ZpatZA5
fS./y=j(X
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。 6GKT yN
$pFk"]=
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 f9']
jJ+
6q%ed
UED
做法如下: }aZrou3E
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ?~)Ak`=
$^Ca:duk
的信息,和一个结果集List: /2h][zrZ[.
java代码: ){tPP$-i=
|s`Kd-'|q
?L`ZKRD
/*Created on 2005-6-13*/ ~hD{coVTI
package com.adt.bo; C
ktX0
.;slrg(5F
import java.util.List; *g$agyOfh
X')S;KW
import org.flyware.util.page.Page; $,P\)</VR
=>YvA>izE
/** !`C%Fkq
* @author Joa T~:_}J
*/ GYqJ!,
publicclass Result { cQ,9Rnfl,
h[H%:743
private Page page; Ej|A
; &E
m0Z7N5v)
private List content; "%kGRHq
c
*1S}us
/** RHXvee55
* The default constructor 1"$R 3@s;
*/ tDU}rI8?
public Result(){ ;z0"Ox=7
super(); )l{A{f6O
} YOKR//|3
N
^f}ui i
/** >
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* The constructor using fields ,TJ/3_ lH
* =kO@ Gk?
* @param page 5Jw"{V?Ak
* @param content fKYKW?g;)Z
*/ H PTHF
public Result(Page page, List content){ "GLYyC
this.page = page; \^m.dIPdO
this.content = content; LT(?#)D
} TMY{OI8 a
>D3zV.R
/** Hir(6Bt
* @return Returns the content. (uT^Nn9L=
*/ /Tcb\:`9
publicList getContent(){ ^yD"d =z
return content; &vkp?UH
} zP|*(*
lrn+d$!@
/** Zx9.p Fc"
* @return Returns the page. r8+*|$K
*/ 9;pzzZ
public Page getPage(){ ^Yr|K
return page; IrUi
Eq
} {DS\!0T-X
@?vLAsp\
/** xBt<Yt"
* @param content `rq<jtf+
* The content to set. ,0.|P`|w
*/ (L:`ojiU
public void setContent(List content){ 'XEK&Yi1
this.content = content; #!Ze\fOC
} ?KCxrzf
x57'Cg \
/** 2|
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* @param page y\@SC\jk|
* The page to set. <%/:w/
*/ s8yCC#H"
publicvoid setPage(Page page){ "&Ff[O*
this.page = page; 6yp+h
} |zb`&tv}
} oX#9RW/ >I
-P*xyI
9g4QVo|
jvWI_Fto
LEA;dSf
2. 编写业务逻辑接口,并实现它(UserManager, ?{n>EvLY
=;g= GcVK
UserManagerImpl) QWKs[yfdo
java代码: )I?RMR
y
'mlee
#,)PN @P
/*Created on 2005-7-15*/ 3^'#ny?l
package com.adt.service; GU5W|bS
6,a%&1_
import net.sf.hibernate.HibernateException; 4 ;^g MI9
B6(h7~0(<
import org.flyware.util.page.Page; 5UPPk$8`
(UXv,_"nU
import com.adt.bo.Result; \N4d_fPj
`)LIVi"(D
/** v^;-@ddr
* @author Joa 7<fL[2-
*/ mQFa/7FX
publicinterface UserManager { $e>/?Ss
Cv0&prt
public Result listUser(Page page)throws QZ?O;K1|y
'+tKvTU;
HibernateException; HqB|SWyK
VVgsLQd
} Ko@zk<~"[
+tPx0>p;
*ZX!EjICk
B,w:DX
P4i3y{$V
java代码: KU*`f{|
_F3KFQ4,S-
`B:B7Cpvn
/*Created on 2005-7-15*/ CG CQa0
package com.adt.service.impl; u0wn=Dg
#"|"cYi,
import java.util.List; iJEB?y
N\c&PS
import net.sf.hibernate.HibernateException; T4Xtuu1
4,gol?a
import org.flyware.util.page.Page; G OH
import org.flyware.util.page.PageUtil;
,0BR-#
4c
import com.adt.bo.Result; ;5-R=e(KA
import com.adt.dao.UserDAO; ]s f2"~v
import com.adt.exception.ObjectNotFoundException; zoJ_=- *s
import com.adt.service.UserManager; Oi6f8*,
vU ?b"n
/** GJ.kkTMT
* @author Joa OiYNH~hv
*/ u,:CJ[3
publicclass UserManagerImpl implements UserManager { j
l}!T[5
Fecx';_1`
private UserDAO userDAO; q;CayN'I
w 9/nVu
/** >0kmRVd
* @param userDAO The userDAO to set. [0h* &
*/ xi;/^)r
publicvoid setUserDAO(UserDAO userDAO){ dK[*
this.userDAO = userDAO; _{[k[]
} MV%
:ES?
+Gk!
t]dy
/* (non-Javadoc) '2wXV;`
* @see com.adt.service.UserManager#listUser ,}eRnl\
Y;'VosTD
(org.flyware.util.page.Page) F_ ,L2J
*/ ;r g H}r
public Result listUser(Page page)throws t|go5DXz4
AD~~e%
s=
HibernateException, ObjectNotFoundException { 5{8x*PSl
int totalRecords = userDAO.getUserCount(); (y-x01H
if(totalRecords == 0) <WZ1-
throw new ObjectNotFoundException -q'xC: m
i7i|370
("userNotExist"); #;wkr))
page = PageUtil.createPage(page, totalRecords); Uzan7A
List users = userDAO.getUserByPage(page); - 3C* P
returnnew Result(page, users); muL>g_H
} LvSP #$f
EC^Ev|PB\u
} b24NL'jm
.jvSAV5B
b*btkaVue
2N
L:\%wz
Cf.pTYSl
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 NvQY7C
|WD,\=J2
询,接下来编写UserDAO的代码: #citwMW
3. UserDAO 和 UserDAOImpl: l,imT$u
java代码: #]5&mKi
V}vl2o
&&]"Y!r -
/*Created on 2005-7-15*/ =-OCM*5~S
package com.adt.dao; t}5'(9
,:0Q1~8
import java.util.List;
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2neF<H?^o
import org.flyware.util.page.Page; >P<k[vF
Ymwx(Pm
import net.sf.hibernate.HibernateException; kS@9c _3S
I>A^5nk
/** bs<WH`P
* @author Joa =XZF.ur
*/ R=][>\7]}
publicinterface UserDAO extends BaseDAO { Qh)|FQ[s$r
!L&=?CX
publicList getUserByName(String name)throws Zp/qs
z(]
^2&O3s
HibernateException; Uq9,(tV`6g
wQF&GGYR
publicint getUserCount()throws HibernateException; <7vI h0
",MK'\E
publicList getUserByPage(Page page)throws I><99cwFI
xTa4.ZXg
HibernateException; "o\6k"_c>
hN>('S-cq
} ^BF@j4*~
0C7thl{Dms
;']vY
.fio<mqi
a-z23$3
java代码: UPfFT^=y
iFAoAw(
gE-w]/1zD5
/*Created on 2005-7-15*/
q8'@dH
package com.adt.dao.impl; M9uH&CD6U
H$k![K6Uj
import java.util.List; ?=/}Ft
zPX=MfF
import org.flyware.util.page.Page; @&~OB/7B:
az:~{f*-
import net.sf.hibernate.HibernateException; ?:#>^eWYe7
import net.sf.hibernate.Query; (5f5P84x
t7U,AQ=;P5
import com.adt.dao.UserDAO; 4=?Ok":8
8>% jZ%`a
/** /{eih]`x(
* @author Joa ,wry u|7"$
*/ 7| h3.
public class UserDAOImpl extends BaseDAOHibernateImpl >.!5M L\
9E->;0-
implements UserDAO { H3p4,Y}'#
+P>
A
P&
/* (non-Javadoc) ^Ff~j&L@{
* @see com.adt.dao.UserDAO#getUserByName !Zk%P
f^[{k
{t
(java.lang.String) ="#:=i]
*/ Y\z^\k
publicList getUserByName(String name)throws ,p[\fT($]
\,@Yl.,+
HibernateException { V'HlAQr
String querySentence = "FROM user in class #VQGN2bK.
S`GXiwk
com.adt.po.User WHERE user.name=:name"; C$AIP\j-
)
Query query = getSession().createQuery 3]:p!Y`$
)|{1&F1
(querySentence); UtW"U0A
query.setParameter("name", name); c{]r{FAx9o
return query.list(); 'y+bx?3Z
} p5twL
x8SM,2ud
/* (non-Javadoc) _Cv[`e.
* @see com.adt.dao.UserDAO#getUserCount() *uI hxMX
*/ K-"HcHuF
publicint getUserCount()throws HibernateException { 3zA8pI w
int count = 0; a.Rp#}f
String querySentence = "SELECT count(*) FROM 1,%#O;ya
rHC+nou
user in class com.adt.po.User"; RF,=bOr19
Query query = getSession().createQuery Mu_mm/U_
N:PA/V^z
(querySentence); 7(|3 OR+
count = ((Integer)query.iterate().next bgzT3KZ
'1kj:Np
()).intValue(); Zgy2Pot
return count; .qb_/#Bas
} <u x*r#a!d
{d?4;Kd
/* (non-Javadoc) ,#'o)O#
* @see com.adt.dao.UserDAO#getUserByPage ?|Q5]rhs
VtzyB
(org.flyware.util.page.Page) RV#uy]
*/ f)AW !/
publicList getUserByPage(Page page)throws ! 6p)t[s
v8'`gY
HibernateException { y3@x*_K8
String querySentence = "FROM user in class (Q h7bfd
A&}nRP9
com.adt.po.User"; Ch \ed|u
Query query = getSession().createQuery {'c%#\
WDH[kJ
(querySentence);
#8Id:56
query.setFirstResult(page.getBeginIndex()) z!1/_]WJ,
.setMaxResults(page.getEveryPage()); E-tNB{r@
return query.list(); -}N\REXE
} } TX'Z?Lq
D|Ih e%w-
} <R`,zE@t'(
ku[=QsMv
X>@.-{6T
iu6WGmR
o trTrh
至此,一个完整的分页程序完成。前台的只需要调用 gGiV1jN_
~Q$c!=
userManager.listUser(page)即可得到一个Page对象和结果集对象 eRl?9
:AqnWy
的综合体,而传入的参数page对象则可以由前台传入,如果用 z)<pqN
4|@FO}rK[l
webwork,甚至可以直接在配置文件中指定。 0LHiOav
Kz3h]/A.
下面给出一个webwork调用示例: j]F#p R}p
java代码: #/B~G.+(
MMxoKL
IYM@(c@ld0
/*Created on 2005-6-17*/ xeP;"J}
package com.adt.action.user; u>Axq3F
-B3wRAEt
import java.util.List; *p#YK|
XvzV
lKL
import org.apache.commons.logging.Log; ?/l}(t$H
import org.apache.commons.logging.LogFactory; Xv5Ev@T
import org.flyware.util.page.Page; Y(I*%=:$
|H+k?C-w
import com.adt.bo.Result; ZAo)_za&mH
import com.adt.service.UserService; Y%?!AmER
import com.opensymphony.xwork.Action; vu.S>2Wv
s!o<Pd yJK
/** X $9D0;L
* @author Joa E~Up\f
*/ aIt
0;D
publicclass ListUser implementsAction{ Am=PUQF$
k0e|8g X
privatestaticfinal Log logger = LogFactory.getLog #Mem2cz
1:{O RX[;
(ListUser.class); jXDzjt94J
zk 'e6
private UserService userService; 7dg
5HH
qYu!:xa8
private Page page; C@?e`=9(
%`T^qh_dE
privateList users; h&)vdCCk
A$"$`)P!
/* #u=O 5%.
* (non-Javadoc) Ff#N|L'9_
* fN*4(yw
* @see com.opensymphony.xwork.Action#execute() ubC JZ"!
*/ k#=leu"I
publicString execute()throwsException{ 7quwc'!
Result result = userService.listUser(page); r+#V{oE_
page = result.getPage(); = cI\OsV&?
users = result.getContent(); Y`O}]*{>8R
return SUCCESS; Y)j,(9
} k}0
={i&F
/** +$m skj0s
* @return Returns the page. ]MA)='~
*/ bQN4ozSi
public Page getPage(){ by
y1MgQd
return page; O"-PNF,J
} _467~5JkU
lSbM)gL
/** 0!'M#'m
* @return Returns the users. O7CYpn4<7
*/ xo_k"'f+
publicList getUsers(){ +U/ "F|M
return users; Lp]C![\>U
} (uK), *6B
Tx?@*Q
/** rnBeL _8 C
* @param page e"H+sM26-
* The page to set. {)[g
*/ Umwg
iw
publicvoid setPage(Page page){ vls> 6h
this.page = page; [c!vsh]^
}
iIEIGQx
YIk6:W{
/** |v'5*n9
* @param users +p}Xmn
* The users to set. oJu4vGy0
*/ r~Ubgd ]U
publicvoid setUsers(List users){ rMFZ#38d
this.users = users; ]:#$6D"
} ds[Z=_Ll
Mc3h
R0
/** *U^I`j[u
* @param userService BH*]OXW\
* The userService to set. lRK?%~
*/ sF3
l##Wv
publicvoid setUserService(UserService userService){ PWD]qtr
this.userService = userService; l3|>*szX
} MmX[xk
} R]sjG<
i@j ?<
<:7e4#
tJ_@AcF
n$0)gKN7
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, z'K7J'(R
$I0a2Z=dP
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 W2(=m!:U
z}N^`_ *
么只需要: ~4` ec
java代码: yWk:u 5
C)^\?DH
vCo}-b-j
<?xml version="1.0"?> VzM@DM]= ~
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork vgZPDf|
ghQsS|)p.
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 0 S8{VZpy
!3M!p&
1.0.dtd"> 95&sFT
C
4GejT(U
<xwork> 4i&!V9@:
'u%;6'y
<package name="user" extends="webwork- Z:gsguX
AG%es0D[H
interceptors"> ]b=A/*z
)4~XZt1r
<!-- The default interceptor stack name Jpnp'
.@Sh,^ v
--> RXvcy<
<default-interceptor-ref H$iMP.AK
\/%Q PE8
name="myDefaultWebStack"/> u}0t`w:
xW )8mv?4n
<action name="listUser" `fVA.%
(P]^5D
class="com.adt.action.user.ListUser"> BeCr){,3
<param ]= D
*4\ub:9
name="page.everyPage">10</param> ^w}Ib']X
<result o"CqVRR
yf>,oNIAg
name="success">/user/user_list.jsp</result> SygsZv&LZ
</action> g+{MvSj$
?UIb!k>
</package> 1:V/['|*g)
6UP3Ij
</xwork> UM^hF%
5S?Xl|8E
`b$I)UUm
fkG"72 95A
L7="! I
r2`?Ta
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 aq**w?l
wC@U/?
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 aa3YtNpP
7En~~J3
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 qo![#s
Fd0FG A&L
,FPgs0rrS
cW>`Z:6{K
~$Yuxo
我写的一个用于分页的类,用了泛型了,hoho p`C5jfI
xBd%e-r
java代码: ^U1+D^AJ
yrb%g~ELGn
I*t}gvUt9
package com.intokr.util; artS*fv3r
h<jIg$rA
import java.util.List; VAz+J
!1]xKNp]
/** eVJL|uI|
* 用于分页的类<br> o
W [-?
* 可以用于传递查询的结果也可以用于传送查询的参数<br> RR9s%>^
* oOvbel`;
* @version 0.01 C_;6-Q%V
* @author cheng w%"q=V
*/ Cq'r
'cBZ
public class Paginator<E> { #7) 6X:/O
privateint count = 0; // 总记录数 9EQ,|zf'
privateint p = 1; // 页编号 |MGw$
privateint num = 20; // 每页的记录数 HxAa,+k
privateList<E> results = null; // 结果 z(` kWF1<
OTm"Iwzu@
/** DenCD9 f
* 结果总数 *9 xD]ZZF
*/ |9@;Muq;
publicint getCount(){ R 1\]Y
return count; @ZWKs
} /$Jh5Bv
!o7.L%S
publicvoid setCount(int count){ Iu]P^8
this.count = count; HkCme_y"
} e&kg[jU
{643Dz<e
/** 'McVaPav
* 本结果所在的页码,从1开始 T!AQJ:;1
* $~l:l[Zs
* @return Returns the pageNo. \>Q,AyL
*/ L T!X|O.
publicint getP(){ p^3d1H3
return p; 5^i ^?
} ?J
AzN
EJsb{$u
/** ""=Vt]
* if(p<=0) p=1 #Ki@=*
* fNumY|%3
* @param p (TsgVq]L
*/ -8:@xG2
publicvoid setP(int p){ 7KLq-u-8
if(p <= 0) $$w 1%#F=
p = 1; R8]bi|e)
this.p = p; t `oP;
} ]y/:#^M+
x3
<Lx^;
/** G#>nOB
* 每页记录数量 ME"/%59r
*/ F ry5v?22
publicint getNum(){ KA7nncg;,
return num; ?xega-l
} !cZIoz
xMu6PM<l
/** -`JY] H
* if(num<1) num=1 N_U
D7P1
*/ Ex{]<6UAu
publicvoid setNum(int num){ `K.yE0^i
if(num < 1) o>h>#!e
num = 1; G5Nub9_*X
this.num = num; y+_U6rv[
} ~drNlt9jf
W3#L!&z_wK
/** 5Dd;?T>
* 获得总页数 6\L,L&
*/ VEk|lX;2
publicint getPageNum(){ ]v@,>!Wn
return(count - 1) / num + 1; CEiGjo^
} f3O'lc3
[?A0{#5)8x
/** #N:o)I
* 获得本页的开始编号,为 (p-1)*num+1 G4~J+5m k
*/ /$KW$NH4z
publicint getStart(){ P^z)]K#sw
return(p - 1) * num + 1; 4-AmzU
} ;3_'{
!{+(oDN
/** &^"m6
* @return Returns the results. u=5^xpI<D
*/ k 'o?/
publicList<E> getResults(){ `Bx CTwc
return results; lnhZ!_
} \4DH&gZ[
kK(,FB
public void setResults(List<E> results){ l?d*g&
this.results = results; xK f+.6 wz
} gw-l]@;1
mi+I)b=
public String toString(){ V*)gJg
StringBuilder buff = new StringBuilder 6Yu8ReuL
_F$?Z
(); 0<!BzG
buff.append("{"); @YRBZ6FH
buff.append("count:").append(count); Xg"=,j2
buff.append(",p:").append(p); Gh.02
buff.append(",nump:").append(num); LY7'wONx
buff.append(",results:").append (_D#gr{S=
|1EM )zh6
(results); 5_PD?lg
buff.append("}"); <D?`*#K
return buff.toString(); uKplPze?
} u+N[Cgh
'<O&
:
} Q[ IaA"
*ZRQ4i[+
~*RNJ