Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ij?
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 W^G>cC8.L
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 4Z/f@ZD
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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 U*3uq7
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分页支持类: uJ6DO#d`P
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java代码: x:QgjK
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package com.javaeye.common.util; 'D@-
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import java.util.List; J&T.(
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publicclass PaginationSupport { ;6!Pwb;hY
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publicfinalstaticint PAGESIZE = 30; KG=h&
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privateint pageSize = PAGESIZE; SI=yI-
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privateList items; AGbhJ=tB
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privateint totalCount; Jm42b4
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privateint[] indexes = newint[0]; R~ZFy0
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privateint startIndex = 0; _N@ro
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public PaginationSupport(List items, int 0D&t!$Ibf
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totalCount){ >hr{JJe
setPageSize(PAGESIZE); rp0ZvEX
setTotalCount(totalCount); TsGE cxIg
setItems(items); 4vwTs*eB`
setStartIndex(0); pbU!dOU~e
} [AW"
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public PaginationSupport(List items, int B4mR9HMh
#cCL.p"]
totalCount, int startIndex){ ?! `=X>5
setPageSize(PAGESIZE); 9F*+YG!
setTotalCount(totalCount); QV&D l_
setItems(items); |0%+wB
setStartIndex(startIndex); L*~J%7
} iySRY^
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public PaginationSupport(List items, int G^`1]?
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totalCount, int pageSize, int startIndex){ ANps1w#TP
setPageSize(pageSize); (4Zts0O\
setTotalCount(totalCount); $9ky{T?YG
setItems(items); P`e!Z:
setStartIndex(startIndex); HdPoO;
} nVI!@qW
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publicList getItems(){ PgRDKygE
return items; |e2be1LD
} 6%VV,$p
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publicvoid setItems(List items){ <E0UK^-}
this.items = items; 6KOlY>m]
} `8Lo {P
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publicint getPageSize(){ b&5lY p"d
return pageSize; n2IV2^ "
} E_bO9nRHV
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publicvoid setPageSize(int pageSize){ ;ji pe3LU
this.pageSize = pageSize; X 51Yfr
} jvQ*t_L
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publicint getTotalCount(){ !eUDi(
return totalCount; Cj?L@%"
} _Y[jyD1>
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publicvoid setTotalCount(int totalCount){ p+Y>F\r&w
if(totalCount > 0){ &c*^VL\
this.totalCount = totalCount; u@4V7;L
int count = totalCount / 59Gk3frk(
wW%4d
pageSize; =lu/9
i6
if(totalCount % pageSize > 0) 3dDX8M?
count++; |#*'H*W
indexes = newint[count]; ~jb"5CX
for(int i = 0; i < count; i++){ Ogp"u b 8
indexes = pageSize * z1Ov|Q`
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i; ?PyG/W
} 8zBWIi
}else{ +/ &_v^sC;
this.totalCount = 0; QzAK##9bfa
} qBT.x,$
} %/rMg"f:
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publicint[] getIndexes(){ {iq3|x2[ :
return indexes; YQS5P#
} =Z+nX0qF
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publicvoid setIndexes(int[] indexes){ 0{j&6I2
this.indexes = indexes; &< !Ufa&
} ts8+V<g
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publicint getStartIndex(){ {$1J=JbE
return startIndex; G\a8B#hg
} g38&P3/
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publicvoid setStartIndex(int startIndex){ 1U,1)<z~u
if(totalCount <= 0) 3bNIZ#`|MB
this.startIndex = 0; oQL59XOT4
elseif(startIndex >= totalCount) 8+Bu+|c%f
this.startIndex = indexes aceZ3U>W
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[indexes.length - 1]; n\ Hs@.
elseif(startIndex < 0) leCVK.
this.startIndex = 0; v<9&B94z
else{ $v b,P(
this.startIndex = indexes c~o+WI
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[startIndex / pageSize]; wI5Yn
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} |G/7_+J6
} ^bLRVp1
3!
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publicint getNextIndex(){ P5gN #G
int nextIndex = getStartIndex() + wP/A^Rs
emW:C-/h/@
pageSize; j.:h5Y^N
if(nextIndex >= totalCount) dr<<! q /
return getStartIndex(); 178Mb\8
else zT ZVehEe
return nextIndex; ;;)`c/$
} '>(.%@
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publicint getPreviousIndex(){ qSx(X!YS
int previousIndex = getStartIndex() - 7zTqNnPnf
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pageSize; {5|("0[F
if(previousIndex < 0) @d&/?^dp6
return0; #Z~C`n
u
else xE-7P|2
return previousIndex; Hk7K`9
} >b.^kc
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} C_LvZ=
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抽象业务类 yA[({2%
java代码: Pj?Dmk~
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/** MP>n)!R[`
* Created on 2005-7-12 q*)+K9LRk
*/ _DP|-bp D
package com.javaeye.common.business; N]YtLa,t
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import java.io.Serializable; 23DJV);g8
import java.util.List;
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import org.hibernate.Criteria; uENdI2EY8y
import org.hibernate.HibernateException; Zt E##p
import org.hibernate.Session; R \s!*)
import org.hibernate.criterion.DetachedCriteria; W}'WA
import org.hibernate.criterion.Projections; "'Z- UV
import <EO<x D=:
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org.springframework.orm.hibernate3.HibernateCallback; AKu_~bTk
import o{-<L
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org.springframework.orm.hibernate3.support.HibernateDaoS <JI&
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upport; 4-v6=gz.
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import com.javaeye.common.util.PaginationSupport; mW`oq
s* jfMY
public abstract class AbstractManager extends K\Eo z]?
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HibernateDaoSupport { gH:ArfC
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privateboolean cacheQueries = false; d @rs3Q1z
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privateString queryCacheRegion; KhM.Tc
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publicvoid setCacheQueries(boolean ~S(^T9R
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cacheQueries){ FE m=w2
this.cacheQueries = cacheQueries; rj H`
} s'_,:R\VM>
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publicvoid setQueryCacheRegion(String et$uP
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queryCacheRegion){ =3ADT$YHd
this.queryCacheRegion = z \?UGxu}
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queryCacheRegion; E8/rZ~0O~
} N\R=cwk
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publicvoid save(finalObject entity){ F!8=FTb
getHibernateTemplate().save(entity); QB1M3b
} MTmO>V&O
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publicvoid persist(finalObject entity){ *_)E6Y?9
getHibernateTemplate().save(entity);
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} BXTN>d27
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publicvoid update(finalObject entity){ W(@>?$&
getHibernateTemplate().update(entity); 5N1 K~".
} NfF~dK|
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publicvoid delete(finalObject entity){ If.n(t[M9
getHibernateTemplate().delete(entity); pT=2e&
} H~m]nV,r
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publicObject load(finalClass entity, .xpmp6-
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finalSerializable id){ aJ2H.E
return getHibernateTemplate().load (2%>jg0M
){tPP$-i=
(entity, id); u33zceE8
} @)z*BmP
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publicObject get(finalClass entity, uL>:tb
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finalSerializable id){ t F/nah
return getHibernateTemplate().get T~:_}J
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(entity, id); <bX 1,}?
} lJj&kVHb
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publicList findAll(finalClass entity){ 0UD"^zgY
return getHibernateTemplate().find("from yiO31uQt
B"[{]GP BY
" + entity.getName()); ;fx1!:;.
} `
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publicList findByNamedQuery(finalString L?.7\a@
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namedQuery){ DvJB59:_}
return getHibernateTemplate }s6G!v^2""
{jhcZ"#>\
().findByNamedQuery(namedQuery); iUCwKpb9
} 5m3'Gt4
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publicList findByNamedQuery(finalString query, :}y| 4*z
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finalObject parameter){ :H3(w| T/
return getHibernateTemplate 9;pzzZ
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().findByNamedQuery(query, parameter); rr)9Y][l}
} `rq<jtf+
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publicList findByNamedQuery(finalString query, @LHtt/&
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finalObject[] parameters){ X,&xhSzg?
return getHibernateTemplate Y8t
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().findByNamedQuery(query, parameters); `:R-[>5P8
} G ;jF9i
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publicList find(finalString query){ w2@"PGR
return getHibernateTemplate().find %p}qO^%M
*se u&
(query); jPj2
} =;g= GcVK
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publicList find(finalString query, finalObject TXx'7[
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parameter){ >]^>gUmq
return getHibernateTemplate().find xdCs5ko
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(query, parameter); \N4d_fPj
} ,v|CombIc.
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public PaginationSupport findPageByCriteria N*HH,m&
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(final DetachedCriteria detachedCriteria){ >QA/Mi~R
return findPageByCriteria BQE{
p EY>A_F
(detachedCriteria, PaginationSupport.PAGESIZE, 0); !+5C{Hs2
} +_P8'e%Iy
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public PaginationSupport findPageByCriteria n#)PvV~
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(final DetachedCriteria detachedCriteria, finalint u0wn=Dg
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startIndex){ o; 6fvn
return findPageByCriteria "^Y6ctw
id3)6}
(detachedCriteria, PaginationSupport.PAGESIZE, &3jBE--
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startIndex); te4F"SEf
} C{8i7D
:
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public PaginationSupport findPageByCriteria Zlr{L]c
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(final DetachedCriteria detachedCriteria, finalint "[#@;{@Gt
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pageSize, #4Dn@Gqh.Y
finalint startIndex){ #Tup]czO
return(PaginationSupport) KuIBYaK,
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getHibernateTemplate().execute(new HibernateCallback(){ aytq4Ts
publicObject doInHibernate BhOXXa{B
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(Session session)throws HibernateException { 0m]~J_
Criteria criteria = oNiToFbQu
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detachedCriteria.getExecutableCriteria(session); -q'xC: m
int totalCount = LvSP #$f
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((Integer) criteria.setProjection(Projections.rowCount }f<fgY
fO[Rf_
()).uniqueResult()).intValue(); *p" "YEN
criteria.setProjection |WD,\=J2
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(null); +io;K]C
List items = 2$o2.$i81
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criteria.setFirstResult(startIndex).setMaxResults g4~X#}:z$O
,maAw}=
(pageSize).list(); Bpk@ {E9
PaginationSupport ps = 2neF<H?^o
mXxZM;P[
new PaginationSupport(items, totalCount, pageSize, Sf+(1_^`t
a)I=U[
startIndex); R=][>\7]}
return ps; DBu)xr}7A
} o 8~f
}, true); g28S3 '2
} s|{^ }4{
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public List findAllByCriteria(final ZTQ$Ol+{q
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DetachedCriteria detachedCriteria){ IgzCh
return(List) getHibernateTemplate *Gk<"pEeS
_ 4~ng#M*
().execute(new HibernateCallback(){ X";QA":
publicObject doInHibernate J]n7| L
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(Session session)throws HibernateException { kr/1Dsr4
Criteria criteria = C$N4
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detachedCriteria.getExecutableCriteria(session); q;1VF;<"vH
return criteria.list(); +XU$GSw3(
} #Qtg\X
}, true); *@\?}cX
} Ev$-PX
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public int getCountByCriteria(final b6LC$"t0
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DetachedCriteria detachedCriteria){ +WV_`Rx#
Integer count = (Integer) dVj'
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getHibernateTemplate().execute(new HibernateCallback(){ hr~qt~Oi
publicObject doInHibernate Ov~S2?E8
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(Session session)throws HibernateException { C$AIP\j-
)
Criteria criteria = @w#gRQCl
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detachedCriteria.getExecutableCriteria(session); 94qHY1rp
return ~n8*@9[
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criteria.setProjection(Projections.rowCount t[f9Z
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()).uniqueResult(); bG?WB,1
} "a0u-}/D
}, true); T;4gcJPn"M
return count.intValue(); ig.6[5a\
} Zgy2Pot
} @??c<]9F
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用户在web层构造查询条件detachedCriteria,和可选的 `:bvuc(
#g-*n@
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 >F\rBc&
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PaginationSupport的实例ps。 O=#/DM;
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ps.getItems()得到已分页好的结果集 3"^)bGe
ps.getIndexes()得到分页索引的数组 ]UCk_zWsn1
ps.getTotalCount()得到总结果数 Zjp5\+hHV
ps.getStartIndex()当前分页索引 rmg";(I
ps.getNextIndex()下一页索引 \MFWK#W
ps.getPreviousIndex()上一页索引 =-Q
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 o+)LcoPu
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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 {HRxyAI!
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一下代码重构了。 Eip~~2
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我把原本我的做法也提供出来供大家讨论吧: V Q,\O
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首先,为了实现分页查询,我封装了一个Page类: vu.S>2Wv
java代码: y/sWy1P7
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/*Created on 2005-4-14*/ ++{+
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package org.flyware.util.page; C#?d=x
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/** n xh/&%
* @author Joa IrwF
B
* a+a%}76N
*/ Mi/'4~0Y
publicclass Page { %CE@}
jf)JPa_
/** imply if the page has previous page */ ;,B@84'
privateboolean hasPrePage; knK=ENf;e
\q`+
/** imply if the page has next page */ %k;FxUKi
privateboolean hasNextPage; HG3>RcB
z#E,96R
/** the number of every page */ 2,e|,N"zN
privateint everyPage; &\]f!'jV
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/** the total page number */ wsGq>F~
privateint totalPage; pu)9"Ad[ G
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/** the number of current page */ -JO46
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privateint currentPage; vLT12v:)`
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/** the begin index of the records by the current dv9Pb5i
p*&LEjaVM4
query */ 4!s k3Cw{
privateint beginIndex; TtjSLkF
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/** The default constructor */ ZG[0rvW
public Page(){ jeBj
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} r~Ubgd ]U
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/** construct the page by everyPage +4p;4/=
* @param everyPage C`_D{r
* */ ,Y5 4(>>%
public Page(int everyPage){ sF3
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this.everyPage = everyPage; ,H(vD,54g
} ]~M{@h!<
+~{nU'
/** The whole constructor */ E|uXi)!.x
public Page(boolean hasPrePage, boolean hasNextPage, ^Jpd9KK
-^
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43Uy<%yb>}
int everyPage, int totalPage, r$eL-jQmn
int currentPage, int beginIndex){ #YVDOR{z
this.hasPrePage = hasPrePage; *7V{yK$O|
this.hasNextPage = hasNextPage; juYt =
this.everyPage = everyPage; p;Ok.cXVp
this.totalPage = totalPage; m/B9)JzY
this.currentPage = currentPage; 95&sFT
C
this.beginIndex = beginIndex; cW/~4.v$
} Sh6 NgO
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/** "MP{z~Mmj
* @return JJOs
L!@
* Returns the beginIndex. o@~gg*
*/ h4xdE0
publicint getBeginIndex(){ GuDD7~qxY
return beginIndex; F+-MafN7Y
} U]&%EqLS
dM.Ow!j
/** ]= D
* @param beginIndex Qn cS&
* The beginIndex to set. yf>,oNIAg
*/ zMg^2{0L
publicvoid setBeginIndex(int beginIndex){ yG_.|%e
this.beginIndex = beginIndex; Y(mwJud|
} *Y>'v%
u-cC}DP
/** L)"w-,zy
* @return %['F[Mo
* Returns the currentPage. KDzIarC
*/ N.J:Qn`(
publicint getCurrentPage(){ [qo*,CRz
return currentPage; $>`8'I
} z`6KX93
#Z5~a9rO
/** yZ6X$I:C
* @param currentPage @g?z>n
n
* The currentPage to set. ,peFNpi
*/ ?q7Gs)B=^'
publicvoid setCurrentPage(int currentPage){ DvKMb-*S
this.currentPage = currentPage; 4K,&Q/Vdd7
} |LhuZ_;1xo
7]
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/** RAa1KOxZX
* @return Cq'r
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* Returns the everyPage. }?$Mh)
*/ c73ZEd+j
publicint getEveryPage(){ {K}+$jzGVt
return everyPage; ?/ g(Y
} -rrg?4
fe,CY5B{
/** 34:=A0z
* @param everyPage ^Y!`wp2vn
* The everyPage to set.
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*/ 7hQl,v< 5
publicvoid setEveryPage(int everyPage){ uDUSR+E>
this.everyPage = everyPage; P#]jPW
} m[rJFSpef
{M5IJt"{4b
/** n%hnL$!z
* @return CK%W+";
* Returns the hasNextPage. :2+:(^l
*/ O\z%6:'M
publicboolean getHasNextPage(){ 'L7.a'
return hasNextPage; ^|2qD:
;
} 0
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/** t `oP;
* @param hasNextPage 6C=.8eP
* The hasNextPage to set. <7+.5iB3
*/ ?6gI8K6X
publicvoid setHasNextPage(boolean hasNextPage){
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this.hasNextPage = hasNextPage; /6fs h7 \
} 2TO1i0
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/** %\u>%s<9
* @return (G
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* Returns the hasPrePage. \ U_DTI
*/ +Y+kx"8
publicboolean getHasPrePage(){ O@VmV>m
return hasPrePage; MH-,+-Eq
} ]v@,>!Wn
>ZT3gp?E
/** 6/) A6Tt
* @param hasPrePage #=2~MXa@z7
* The hasPrePage to set. (uE_mEIsv
*/ Tu"](|I>
publicvoid setHasPrePage(boolean hasPrePage){ E^G=
this.hasPrePage = hasPrePage; YR>x h2< 9
} V3S`8VI
pE#0949
/** H'0S;A+Y6
* @return Returns the totalPage. kK(,FB
* '?nhpT^
*/ 3z#16*
publicint getTotalPage(){ V_:/#G]jeG
return totalPage; *e=e7KC6kI
} {chl+au*l
V*)gJg
/** ?V+=uTCq
* @param totalPage :D EZ$gi
* The totalPage to set. M~v{\!S
*/ 8Vp"}(Q
publicvoid setTotalPage(int totalPage){ [>fE{~Y
this.totalPage = totalPage; (_D#gr{S=
} "{}5uth
<D?`*#K
} sBh|y F,
}Q*8QV
SI\zW[IL
Z^b1i`v
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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 Wh7$')@
VrHFM(RNe
个PageUtil,负责对Page对象进行构造: W,vb7v'
java代码: Gg/K
IP-mo!Y.
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/*Created on 2005-4-14*/ v6FYlKU@8
package org.flyware.util.page; \ /o`CV{O
>qOhzbAH{<
import org.apache.commons.logging.Log; =2<
>dM#`
import org.apache.commons.logging.LogFactory; l+@NjZGm<
<~]s+"oVc
/** qT(j%F
* @author Joa .Sm7na
K
* yB&s2J
*/ #P1k5!u
publicclass PageUtil { Pr" 2d\
P9gIKOOx#4
privatestaticfinal Log logger = LogFactory.getLog i-$]Tg
Vg0Rc t
(PageUtil.class); A+AqlM+$i
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/** (JOge~U
* Use the origin page to create a new page Xfe,ZC)
* @param page `uY77co6
* @param totalRecords x5s Yo\
* @return Y*0mC "n}
*/ {qK>A?9
publicstatic Page createPage(Page page, int &W*9'vSm.
074)(X&:x
totalRecords){ RCKb5p9
return createPage(page.getEveryPage(), Bf.@B0\
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page.getCurrentPage(), totalRecords); (k4> I"x)
} ngE5$}UM
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/** w\!aKeP'
* the basic page utils not including exception +TL5yuA
z^bv)u
handler dL!PpLR$2
* @param everyPage sSU p7V
* @param currentPage KFx4"f%
* @param totalRecords zyTeF~_
* @return page ;.+sz(:hm
*/ w,n&K6<
publicstatic Page createPage(int everyPage, int v25]}9 /C
1?\G6T
currentPage, int totalRecords){ Dn1aaN6
everyPage = getEveryPage(everyPage); \b6H4aQii
currentPage = getCurrentPage(currentPage); ye4 T2=
int beginIndex = getBeginIndex(everyPage, UU~S{!*+L
7b7@"Zw*
currentPage); (hr*.NS#
int totalPage = getTotalPage(everyPage, 7,X5]U&A<x
k <SFl
totalRecords); 1ayL*tr
boolean hasNextPage = hasNextPage(currentPage, &?59{B.mD
"k&QS@l
totalPage); g$+ $@~
boolean hasPrePage = hasPrePage(currentPage); :@K1pAh 4
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returnnew Page(hasPrePage, hasNextPage, h'%iY6!fA
everyPage, totalPage, /r2*le (H
currentPage, ?QR13l(
^N#z&oh
beginIndex); O(pa;&"
} F)XO5CBK
;XAj/6pm
privatestaticint getEveryPage(int everyPage){ K FM x(fD
return everyPage == 0 ? 10 : everyPage; <l>o6K
} q.I
rW),xfo0
privatestaticint getCurrentPage(int currentPage){ m}`!FaB #
return currentPage == 0 ? 1 : currentPage; Oc A;+}>
} N#C,q&;
n06T6oc
privatestaticint getBeginIndex(int everyPage, int 8p"R4
,Kl6vw8Htg
currentPage){ a\_?zi]s&,
return(currentPage - 1) * everyPage; 3pU/Zbb,:
} ,.6)y1!
T'8d|$X
privatestaticint getTotalPage(int everyPage, int [cfKvROG
,;%F\<b
totalRecords){ Z2@_F7cXt
int totalPage = 0; 5,vw%F-m
6Z,GD
if(totalRecords % everyPage == 0) HnlCEW,^o
totalPage = totalRecords / everyPage; L>@:Xo@
else V;@kWE>3
totalPage = totalRecords / everyPage + 1 ; &[#iM0;)W0
=pa
F6!AB
return totalPage;
Fm-D>PR
} yUY* l@v]
%Bxp
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privatestaticboolean hasPrePage(int currentPage){ Aq3.%,X2H
return currentPage == 1 ? false : true; M?[~_0_J
} rP%B#%;S"
vHmsS\\~9
privatestaticboolean hasNextPage(int currentPage, .+#<~Jv
H5,rp4H9
int totalPage){ og$%`o:{
return currentPage == totalPage || totalPage == |K(jXZ)
k\/idd[
0 ? false : true; -h%!#g
} :@oy5zib
e09('SON(
F<9S,
} N0mP
EF2
rb_FBa%
"o{o9.w
(U?*Z/
G_cWp D/
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 j84g6; 4Dv
S!oG|%VuB#
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 N"k
IQe*}1
8`]1Nt!*B
做法如下: \g;o9}@3~
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 y/9aI/O'
{];8jdg/?
的信息,和一个结果集List: m ,|)$R
java代码: Y(U+s\X
KEfx2{k b
l!7O2Ai5
/*Created on 2005-6-13*/ L`6 R
package com.adt.bo; 5vSJjhS
+=o?&
import java.util.List; FG@ ')N!g
A8jj]J+
import org.flyware.util.page.Page; [$iKx6\
&ZR} Z7E*=
/** {37v.4d;
* @author Joa bw[s<z|LKA
*/ D *Hy 2eZ.
publicclass Result { mh7JPbX|
yKb+bm&5:'
private Page page; `{v!|.d<
Lbwc2Q,.-
private List content; +#@)C?G,TF
6a MG!_jC
/** nMT"Rp
* The default constructor sk>E(Myo
*/ m2esVvP
public Result(){ $!q(-+(
super(); A^3M~
} %K/zVYGm&
2M`:/ shq
/** a\]glw\;
* The constructor using fields -+)06BqF}
* XcH_Y
* @param page 41oXOB
* @param content QHmF,P
*/ J&w'0
public Result(Page page, List content){ *kM^l!<g
this.page = page; u+_6V
this.content = content; l'm\*=3
} g\~n5=-D
T
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/** i+XHXpk
* @return Returns the content. vDit&Lh{T
*/ @en*JxIM
publicList getContent(){ A.wuB
return content; ,B8u?{O
} F!*tE&Se+
)z
Hib;O
/** sO$X5S C9
* @return Returns the page. X Z4q{^o
*/ `SM37({c
public Page getPage(){ S:YQVj
return page; HB:VpNFn
} W^8MsdM
Q xm:5P
/** bZf}m=C!
* @param content AR?1_]"=
* The content to set. u!@(u!Qz
*/ RIV
+ _}R
public void setContent(List content){ 8lZB3p]X
this.content = content; Zog&:]P'F
} :ND e<6?u
)1iqM]~;B
/** J<h!H
* @param page J2avt
* The page to set. E=$li
*/ {"WfA
publicvoid setPage(Page page){ -.t/c}a#
this.page = page; 8D:0Vhx\I
} ;&OVV+y
} `:#IZ
YQN@;
^+k~{F,)
d]r?mnN W
0 P2lq
2. 编写业务逻辑接口,并实现它(UserManager, HD!2|b~@
g|=1U
UserManagerImpl) <1eD*sC?g
java代码: '4e,
e|r
6R'z3[K9
Cc}3@Nf{/
/*Created on 2005-7-15*/ W'!
I+nh
package com.adt.service; :D:Y-cG*n<
,*m{Q
import net.sf.hibernate.HibernateException; PfjD!=yS=h
sDl@
import org.flyware.util.page.Page; ?X^.2+]*&
dj2w_:&W
import com.adt.bo.Result; |*>s%nF|
BG^)?_69
/** ,R[<+!RS
* @author Joa oZ\zi> Y,
*/ 'BX
U'
publicinterface UserManager { 1TlMB
p>h}k_s
public Result listUser(Page page)throws 4L<;z'
r,Tq";N'
HibernateException; IylfMwLC
0lLg uBW@
} bZ[ay-f6oK
uFnq 3m^u
<Gj]XAoe%
"?S>}G\
@S)p{T5G
java代码: W(o#2;{ln
t*wV<b
}iRRf_
/*Created on 2005-7-15*/ gQ$0 |0O
package com.adt.service.impl; U[G5<&Z^
oD3Q{e
import java.util.List; b&P2VqYgl
L*zfZ&
import net.sf.hibernate.HibernateException; NszqI
/E^j}H{
import org.flyware.util.page.Page; u85?f
import org.flyware.util.page.PageUtil; d6ckvD[
i?n#ge
import com.adt.bo.Result; Sh(XFUJ
import com.adt.dao.UserDAO; QRHM#v S
import com.adt.exception.ObjectNotFoundException; T854}RX[{
import com.adt.service.UserManager; pGP$2
s)}EMDY
/** EfqC_,J*3
* @author Joa -?1ed|I8
*/ :~\ y<
publicclass UserManagerImpl implements UserManager { }*,z~y}V#
3Gt@Fo=
private UserDAO userDAO; <4Ik]Uz^
lin
/** e_dsBmTh
* @param userDAO The userDAO to set. \:>eZl?
*/ Hh'o:j(^
publicvoid setUserDAO(UserDAO userDAO){ xbsX-F
this.userDAO = userDAO; xPMX\aI|l
} O4T_p=Xc
YzYj/,?r
/* (non-Javadoc) Nrzg>WQa
* @see com.adt.service.UserManager#listUser E[M.q;rM
?<~P)aVVj
(org.flyware.util.page.Page) &?M'(` ~
*/ k@Bn}r
public Result listUser(Page page)throws bix}#M
-9yWf8;
HibernateException, ObjectNotFoundException { 28O 3N;a
int totalRecords = userDAO.getUserCount(); tNYCyw{K
if(totalRecords == 0) 7vEZb.~4z
throw new ObjectNotFoundException DHh30b$c
g>H\"cUv
("userNotExist"); !==C@cH<N
page = PageUtil.createPage(page, totalRecords); `.YMbj#T
List users = userDAO.getUserByPage(page); 2x:aMWh
returnnew Result(page, users); 7F8>w 7Y]
} 2$1D+(5;
C[nacAi
} 1VB{dgr
H~~>ut6`
+Ec@qP R&
Bu#\W
o&kgRv[
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ;\gHFG}
Jl{g"N{2u'
询,接下来编写UserDAO的代码: 5Cl;h^R|m
3. UserDAO 和 UserDAOImpl: ef]60OtP
java代码: N>',[4pJ|
?o_D#gG*
eG%Q
3h
/*Created on 2005-7-15*/ ,dSP%?vV
package com.adt.dao; zzZK S
8&++S> <
import java.util.List; }+BbwBm&
HsAKz]Mq
import org.flyware.util.page.Page; v9l|MI15V
d1n*wVl
import net.sf.hibernate.HibernateException; |v= */e
8% `Jf`
/** !z?;L_Lb
* @author Joa Y1L7s H 9
*/ THz=_L6
publicinterface UserDAO extends BaseDAO { K5:>
8aa`0X/6
publicList getUserByName(String name)throws DeGcS1_?
gshgl3
HibernateException; o;7_*=i
#mH4\s
publicint getUserCount()throws HibernateException; KmaMS(A(3
75RQ\_zDu
publicList getUserByPage(Page page)throws |9fGn@-
d/&~IR
HibernateException; \,yX3R3}.~
Xjnv8{X
} !&@!:=X,
<#No t1R
OjBg$f~0F
ip2BvN&
B&4NdL/
java代码: qn#f:xltu
l|'{Cb
9e'9$-z
/*Created on 2005-7-15*/ 2^T`> ?{X
package com.adt.dao.impl; LM?UV)
I-o|~
import java.util.List; /GMT
8^av&u$
import org.flyware.util.page.Page; ;_?RPWZ;MO
B3-;]6
import net.sf.hibernate.HibernateException; q8P$Md-=b1
import net.sf.hibernate.Query; #ybtjsu'"U
)|CF)T-
import com.adt.dao.UserDAO; M3/_E7Qoj
8@-
UvT&o
/** = ,^eQZR:
* @author Joa |)IS[:X
*/ |%xgob
public class UserDAOImpl extends BaseDAOHibernateImpl GV(@(bI*
:;u?TFCRx
implements UserDAO { ELqpIXq#
TE t+At`]
/* (non-Javadoc) 92)e/t iP
* @see com.adt.dao.UserDAO#getUserByName x cA5
#JIh-h@
(java.lang.String) @O Rk
*/ Rw#4 |&
publicList getUserByName(String name)throws K`#bLCXEV0
t/L:Y=7w
HibernateException { >)p8^jX
String querySentence = "FROM user in class l=?G"1
^E349c-|
com.adt.po.User WHERE user.name=:name"; f hS4Gb_
Query query = getSession().createQuery m C&*K
R@Kzdeo
(querySentence); qKL
mL2O
query.setParameter("name", name); }*s%|!{H
return query.list(); A9L
{c!|-
} ,2?S ua/LD
>^q7:x\
/* (non-Javadoc) haW*W=kv)
* @see com.adt.dao.UserDAO#getUserCount() `bx}!;{lx
*/ xgV(0H}Mf
publicint getUserCount()throws HibernateException { J52- qR/
int count = 0; hxQx$
String querySentence = "SELECT count(*) FROM U#=5HzE
236,o
{9e
user in class com.adt.po.User"; Tz{f5c&
Query query = getSession().createQuery z.%K5vrO>
/>q?H)6
(querySentence); D?:AHj%gW
count = ((Integer)query.iterate().next F vt5vQ
(h3f$
()).intValue(); M8HHyV[AmC
return count; J;AwC>N
} ym~
c^ifHCt|
/* (non-Javadoc) Td"_To@jd
* @see com.adt.dao.UserDAO#getUserByPage XFv) ]_G
7g&"clRGO
(org.flyware.util.page.Page) SZ'2/#R>
*/ ?1kXV n$
publicList getUserByPage(Page page)throws >/5'0n_R
F&= X/
HibernateException { N& 683z
String querySentence = "FROM user in class zm7IkYF
B{ptP4As-
com.adt.po.User"; ^vA"3Ixb!
Query query = getSession().createQuery 'W2B**}
mufJ@Y S#
(querySentence); @P@j9yR
query.setFirstResult(page.getBeginIndex()) 4ZAnq{nR4
.setMaxResults(page.getEveryPage()); Op2@En|d
return query.list(); Q?uHdmY*X
} V^[B=|56
aI'MVKwMk
} +8#hi5e
;[,r./XmH
gXP)YN
Un.u{$po
e*?@6E
至此,一个完整的分页程序完成。前台的只需要调用 9H6%\#rw
ys~oJb~
userManager.listUser(page)即可得到一个Page对象和结果集对象 CqkY_z
#i1z&b#@
的综合体,而传入的参数page对象则可以由前台传入,如果用 KdTDBC
2iV/?.<Z&
webwork,甚至可以直接在配置文件中指定。 bAVlL&^@|
$YztLcn
下面给出一个webwork调用示例: 2C59fXfd
java代码: }JlrWJRi
Fk*C8
2k]Jkd,E
/*Created on 2005-6-17*/ _Q=h3(ZI
package com.adt.action.user; zS<idy F`
T5gL
import java.util.List; $FM:8^
C>gC99
import org.apache.commons.logging.Log; (S)jV0
import org.apache.commons.logging.LogFactory; YM<F7tp4
import org.flyware.util.page.Page; !bGMVw6_
|ycN)zuE
import com.adt.bo.Result; p1`")$
import com.adt.service.UserService; k0^t$J
W
import com.opensymphony.xwork.Action; >)6d~
I/`\>Hk
/** u`~,`z^{n
* @author Joa 3Q\k!$zq
*/ V|`w/P9g4
publicclass ListUser implementsAction{ dc=~EG-_rM
(\o &Gl
privatestaticfinal Log logger = LogFactory.getLog FesUE_L2$
RJa1pYK
(ListUser.class); t}x^*I$*
|:b!e
private UserService userService; ,he1WjL
x4^*YZc$,
private Page page; y??^[ sB
:9Mqwgk,;3
privateList users; ,/Usyb,`
uz'MUT(68
/* 4khc*fh
* (non-Javadoc) O&@pi-=o
* C]GW u~QF
* @see com.opensymphony.xwork.Action#execute() _<m yM2z
*/ q)QM+4
publicString execute()throwsException{ Q=n2frW(T
Result result = userService.listUser(page); 8L _]_
page = result.getPage(); %z"${ zw
users = result.getContent(); ;tG@ 6
return SUCCESS; c6~<vV'}
} * G0I2
F$nc9x[S
/** E;-*LT&{
* @return Returns the page. IEeh9:Km
*/ 'd |*n#Dqc
public Page getPage(){ \wM8I-f!
return page; (y!V0iy]
} :=e"D;5
y\@INA^
/** l,@rB+u
* @return Returns the users. cVuT|b^
*/ #CTeZ/g
publicList getUsers(){ *EllE+M{n
return users; mT&?DZ9<
} ~Hb2-V
+Vw]DLWR
/** rPUk%S
* @param page -APbN(Vi
* The page to set. [/GCy0jk
*/ nk.j7tu
publicvoid setPage(Page page){ ,ocAB;K
this.page = page; +Z1y1%a
} #H-EOXy
I'e`?H t
/** E:ti]$$
* @param users 5h@5.-}
* The users to set. v/[*Pze,C
*/ 91\]Dg
publicvoid setUsers(List users){ 2f0qfF
this.users = users; ]CGH )4Pe
} #j4jZBOTM
Vl`!6.F3
/** ~U+W4%f8
* @param userService ,ePl>m:Z
* The userService to set. E@CK.-N|
*/ nl+8C}=u
publicvoid setUserService(UserService userService){ 5j>olz=n}
this.userService = userService; g66x;2Q
} gtRVXgI
} M~Ph/
o@uZU4MM
X1FKcWv
bu,xIT ^
a,eJO ??
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, >TG#
L17{W4
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 /amWf^z
Z}yd`7
么只需要: q$7/X;A
java代码: +6Ye'IOG
S0H|:J
3"LT ''
<?xml version="1.0"?> 6!Uk c'r
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork U$Od)
L|Bjw3K&D
1.0//EN" "http://www.opensymphony.com/xwork/xwork- Z=9gok\
3T~DeqAyw
1.0.dtd"> K:b^@>XH
Mk8k,"RG&Z
<xwork> 6[\1Nzy>
=k##*%
<package name="user" extends="webwork- `*y%[J,I#
NS){D7T
interceptors"> EL(BXJrx{
&?Z<"+B8S
<!-- The default interceptor stack name C@!bd+'
[E)&dl_k
--> &/8B(0<
<default-interceptor-ref FXh*!%"*
0y3C
/>a
name="myDefaultWebStack"/> He1~27+99
}gKY_e3
<action name="listUser" =kjD ]+l
K)GpQ|4:<
class="com.adt.action.user.ListUser"> 9 e;8"rJ?C
<param gdkHaLL"
t@!A1Vr@
name="page.everyPage">10</param> &"d
:+!4h
<result G6p R?K+
dpcU`$kt
name="success">/user/user_list.jsp</result> \0.!al0
</action> ]T._TZ"
\?[ m%$A
</package> XwDt8TxL
B/dJj#
</xwork> *0Wkz'=U
`a5,5}7v%`
]0=THq\H
]l^"A~va
y\Wp}}
Sobp;OZ5
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 0u
bf]Z
f('##pND@
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。 pV*d"~T
T;v^BVn
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 r{wf;5d(
#>2cfZ`6'J
\`W8#fob
I5E+=.T*ar
83F]d+n
我写的一个用于分页的类,用了泛型了,hoho f{U,kCv
ge#P(Itz
java代码: F41g Mg
5")BCA
XsX];I{E,
package com.intokr.util; KN~Rep cz@
YGhHIziI
import java.util.List; Y#FSU#a$<
P_(<?0l
/** R)Dh; XA
* 用于分页的类<br> syk,e4:oA
* 可以用于传递查询的结果也可以用于传送查询的参数<br> :Yn{:%p
* 0oo_m6ie&
* @version 0.01 0G3T.4I
* @author cheng :<uCi\9(
*/ ' wKTWmf?\
public class Paginator<E> { t![972.&
privateint count = 0; // 总记录数 |T{ZDJ+
privateint p = 1; // 页编号 xLw[
aYy4
privateint num = 20; // 每页的记录数 Tvw(Sq};
privateList<E> results = null; // 结果 @}{Fw;,(7n
p<&d