Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 rVDOco+w
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 UMlvu?u2p1
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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 (iY2d_FQ[
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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 X-cP'"
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分页支持类: 4gn|zSe>^
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java代码: {R7m qzt
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package com.javaeye.common.util; Q@cYHFi~+
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import java.util.List; L.%zs
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publicclass PaginationSupport { Eg$Er*)h8
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publicfinalstaticint PAGESIZE = 30; hGo/Ve+@
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privateint pageSize = PAGESIZE; a0hgF_O1
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privateList items; qmq#(%Z <W
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privateint totalCount; bJFqyK:6
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privateint[] indexes = newint[0]; >UV?nXP}
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privateint startIndex = 0; KqWO9d?w.
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public PaginationSupport(List items, int |kqRhR(Ei
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totalCount){ 7h\U}!
setPageSize(PAGESIZE); /@6T~XY M
setTotalCount(totalCount); (b+o$C
setItems(items); zO 6Sl[)
setStartIndex(0); Qe]aI7Ei
} LEY k
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public PaginationSupport(List items, int TR!7@Mu3
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totalCount, int startIndex){ /.:&9 c
setPageSize(PAGESIZE); -nnAe
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setTotalCount(totalCount); ;et(Yi;9
setItems(items); |/!RN[<
setStartIndex(startIndex); q=+wQ[a<
} _j|U>s
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public PaginationSupport(List items, int ]!cLFXa
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totalCount, int pageSize, int startIndex){ 6o]>lQ}
setPageSize(pageSize); 1|5TuljTd
setTotalCount(totalCount); KwhATYWQb
setItems(items); zO3}c3D~q
setStartIndex(startIndex); BV]$=
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} j Ysg'Rl
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publicList getItems(){ 3 /LW6W|
return items; +=(@=PJ6
} qj,^"rp1:
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publicvoid setItems(List items){ @;>Xy!G
this.items = items; {EVHkQ+o
} d6~d)E
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publicint getPageSize(){ Lq{/r+tt/
return pageSize; `
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} L$= a,$
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publicvoid setPageSize(int pageSize){ [P%'p-Hg_
this.pageSize = pageSize; WsR4)U/]v
} O\^D
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publicint getTotalCount(){ #,rP1#?
return totalCount; 1Ewg_/R
} 'o-J)+oa
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publicvoid setTotalCount(int totalCount){ 5!7vD|6
if(totalCount > 0){ o^<W3Z
this.totalCount = totalCount; uN(N2m
int count = totalCount / _)^`+{N<
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pageSize; v#$}3+KVC
if(totalCount % pageSize > 0) *+<H4.W
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count++; $kn"S>jV
indexes = newint[count]; *jo1?
for(int i = 0; i < count; i++){ V-zF'KI[
indexes = pageSize * ;Yn_*M/*
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i; _O"C`]]
} d4A3DTW
}else{ >2;KPV0H
this.totalCount = 0; gYfOa`k
} Bt"*a=t;
} hV"2L4/E
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publicint[] getIndexes(){ -/J2;AkGH
return indexes; ~,reS:9RZ
} RX\@fmK&
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publicvoid setIndexes(int[] indexes){ a|@1RH>7H
this.indexes = indexes; jp+#N
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} v{TISgZ
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publicint getStartIndex(){ `pYL/[5
return startIndex; >
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} Y# ?M%I%j
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publicvoid setStartIndex(int startIndex){ Wx-rW
if(totalCount <= 0) Gm'Ch}E
this.startIndex = 0; Pna2IB+
elseif(startIndex >= totalCount) !8Q9RnGn
this.startIndex = indexes ?&r>`H E
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[indexes.length - 1]; g;<_GL
elseif(startIndex < 0) !FJ_\UST0
this.startIndex = 0; px.]m-
else{ zd#/zUPI
this.startIndex = indexes /A/k13 J
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[startIndex / pageSize]; 6'vt
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} 3W}xYYs]^
} ?3Dsz
{
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publicint getNextIndex(){ Y4n;[nHQ(
int nextIndex = getStartIndex() + H1g"09?h6o
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pageSize; vt-53fa|
if(nextIndex >= totalCount) j 1#T]CDs
return getStartIndex(); bLi>jE.%.
else /-jk_8@a
return nextIndex; 9:jZ3U
} 7U {g'<
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publicint getPreviousIndex(){ ;R.l?Bg
int previousIndex = getStartIndex() - [sH[bmLR
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pageSize; 1]j_4M14aA
if(previousIndex < 0) b?FTwjV+#
return0; 1ssEJ;#s
else Nm]\0m0p-
return previousIndex; 7lz"^
} 27Ve $Q8]v
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} y*5bF0
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抽象业务类 4aQb+t,
java代码: c0%%X!!$
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/** q"[8u ]j
* Created on 2005-7-12 `?ijKZ}y5
*/ 2!35Tj"RFE
package com.javaeye.common.business; =pP0dvn
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import java.io.Serializable; yS[Z%]bvU
import java.util.List; LGm>x
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import org.hibernate.Criteria; eY1$smh t
import org.hibernate.HibernateException; Bld $<uU
import org.hibernate.Session; Q7 Clr{&
import org.hibernate.criterion.DetachedCriteria; 1wa zJj=v
import org.hibernate.criterion.Projections; B|Rnh;B-
import @{Q[M3l
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org.springframework.orm.hibernate3.HibernateCallback; dik+BBu5z
import I~$LIdzw
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org.springframework.orm.hibernate3.support.HibernateDaoS _/_1:ivY8
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upport; 0NB6S&lI^k
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import com.javaeye.common.util.PaginationSupport; .f V-puE
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public abstract class AbstractManager extends wr=h=vXU[
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HibernateDaoSupport { 6.Nu[-?
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privateboolean cacheQueries = false; onM ~*E
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privateString queryCacheRegion; y#AwuC K
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publicvoid setCacheQueries(boolean T{={uzQeJJ
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cacheQueries){ .-;K$'YG
this.cacheQueries = cacheQueries; bUC-}
} nBd!296
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publicvoid setQueryCacheRegion(String &X
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queryCacheRegion){ Tw{H+B"uVz
this.queryCacheRegion = b'^OW
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queryCacheRegion; /LM*nN$%
} w0Fi~:b
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publicvoid save(finalObject entity){ Sq&*K9:z
getHibernateTemplate().save(entity); Wiqy".YY
} v.)'be*u
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publicvoid persist(finalObject entity){ GA{>=Q_~
getHibernateTemplate().save(entity); Eo\#*Cv*
} WIXzxI<)
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publicvoid update(finalObject entity){ kwdmw_
getHibernateTemplate().update(entity); h)q:nlKUW
} ]nN']?{7PW
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publicvoid delete(finalObject entity){ -9/YS
getHibernateTemplate().delete(entity); Q;{yIa$ $
} t'4hWNR'
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publicObject load(finalClass entity, )$yqJ6y5
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finalSerializable id){ ?rWqFM:hb
return getHibernateTemplate().load it\{#rb=4
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(entity, id); bK; -X cm
} 3 S:}fPR
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publicObject get(finalClass entity, Wt"@?#L
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finalSerializable id){ |!dyk<}oIu
return getHibernateTemplate().get _< 69d
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(entity, id); j DcE_55o
} z7MJxjH
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publicList findAll(finalClass entity){ nTY`1w.;
return getHibernateTemplate().find("from eg)=^b
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" + entity.getName()); a<sEd p
} b=-<4Vu*\
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publicList findByNamedQuery(finalString KwWqsuju
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namedQuery){ 29u"\f a
return getHibernateTemplate 88d0`6K-9
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().findByNamedQuery(namedQuery); tHXt*tzq
} 6YrkS;_HS
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publicList findByNamedQuery(finalString query, 6=90 wu3
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finalObject parameter){ Hy|$7]1
return getHibernateTemplate O\XN/R3
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().findByNamedQuery(query, parameter); ]0xbvJ8oK
} SYB
}
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publicList findByNamedQuery(finalString query, E92dSLhs5
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finalObject[] parameters){ R"!.|fH6
return getHibernateTemplate '7
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().findByNamedQuery(query, parameters); %&4sHDP
} D._q'v<
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publicList find(finalString query){ !a~>;+
return getHibernateTemplate().find d vkA-9
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(query); X;v/$=-mz
} 6fY(u7m|p
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publicList find(finalString query, finalObject BGodrb1
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parameter){ b3H~a2"d
return getHibernateTemplate().find $9+}$lpPd
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(query, parameter); k^p|H:
} >wdR4!x!?
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public PaginationSupport findPageByCriteria 4.|]R8Mn
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(final DetachedCriteria detachedCriteria){ `w@fxv
return findPageByCriteria 2l{g$44
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); C=h$8Q
} 1V+a;-?
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public PaginationSupport findPageByCriteria >9Fs)R]P
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(final DetachedCriteria detachedCriteria, finalint J1 a/U@"
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startIndex){ x5WFPY$wM
return findPageByCriteria ?2
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(detachedCriteria, PaginationSupport.PAGESIZE, gPT-zul
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startIndex); Vu*yEF}
} S3MMyS8
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public PaginationSupport findPageByCriteria tU}CRh
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(final DetachedCriteria detachedCriteria, finalint aM9^V MOb
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pageSize, w_ kHy_)
finalint startIndex){ % rRYT8
return(PaginationSupport) ']ya_ v~e
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getHibernateTemplate().execute(new HibernateCallback(){ mK%!9F
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publicObject doInHibernate !qV{OXdrB
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(Session session)throws HibernateException { js^@tgf$x&
Criteria criteria = )xiic3F
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detachedCriteria.getExecutableCriteria(session); VSx[{yn
int totalCount = _ ;O$ot\5
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((Integer) criteria.setProjection(Projections.rowCount u&I?LZ-=,
ecA:y!N
()).uniqueResult()).intValue(); -n?|,cO
criteria.setProjection -w1U/o.
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(null); uH^/\
List items = MG*#-<OV.
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criteria.setFirstResult(startIndex).setMaxResults L~"~C(g
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(pageSize).list(); -N<s =
PaginationSupport ps = x>A(016:C
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new PaginationSupport(items, totalCount, pageSize, zy(sekX;
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startIndex); @.yp IE\
return ps; rZLTai}`>
} WogJ~N,d53
}, true); %`F6>J
} skh6L!6*<
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public List findAllByCriteria(final = 7d{lK
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DetachedCriteria detachedCriteria){ s]#D;i8
return(List) getHibernateTemplate f>k]{W Y
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().execute(new HibernateCallback(){ 3lcd:=
publicObject doInHibernate (TM1(<j
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(Session session)throws HibernateException { 12U1DEd>-
Criteria criteria = _Jx.?8
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detachedCriteria.getExecutableCriteria(session); zlco?Rt
return criteria.list(); vOy;=0$
} [G>8N5@*
}, true); %JeT,{
} "_WOtJr
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public int getCountByCriteria(final % 3d59O
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DetachedCriteria detachedCriteria){ 0"o%=i;
Integer count = (Integer) ,#W>E,UU
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getHibernateTemplate().execute(new HibernateCallback(){ V]dzKNFi
publicObject doInHibernate R".~{6
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(Session session)throws HibernateException { `n7*6l<k~4
Criteria criteria = %$}aWzQxll
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detachedCriteria.getExecutableCriteria(session); _;/onM
return )65 o
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criteria.setProjection(Projections.rowCount C +S
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()).uniqueResult(); ,j\1UAa
} q;a"M7
}, true); mucKmb/
return count.intValue(); x8
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} {ZQ|Ydpk
} 9>?3FMKdY
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用户在web层构造查询条件detachedCriteria,和可选的 _voU^-
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 7HfA{.|m
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PaginationSupport的实例ps。 ]$7dkP
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ps.getItems()得到已分页好的结果集 /WqiGkHV*
ps.getIndexes()得到分页索引的数组 <E/"v
ps.getTotalCount()得到总结果数 JR>v
ps.getStartIndex()当前分页索引 e+416
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ps.getNextIndex()下一页索引 mtfEK3?2*
ps.getPreviousIndex()上一页索引 cvSr><(
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ?
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 Iq/V[v
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一下代码重构了。 P[q` {TdV
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我把原本我的做法也提供出来供大家讨论吧: Fh[Gq
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首先,为了实现分页查询,我封装了一个Page类: Fke_ms=I^
java代码: GJLe733o
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/*Created on 2005-4-14*/ w]-,X`
package org.flyware.util.page; xNLvK:@0p
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/** :Ca]/ ]]
* @author Joa vJ `'x
* +#$(>6Zu"{
*/ \7l%@
publicclass Page { Wu:@+~J.h
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/** imply if the page has previous page */ (=de#wh2]
privateboolean hasPrePage; IJnh@?BC
iD/r8_}
/** imply if the page has next page */ !}[cY76_
privateboolean hasNextPage; ueimTX k
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/** the number of every page */ gr&Rkuyfv
privateint everyPage; B^{87YR
hp:8e@
/** the total page number */ VlLc[eVV
privateint totalPage; aucQZD-_"
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/** the number of current page */ ab5uZ0@
privateint currentPage; IQ9jTkW l
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/** the begin index of the records by the current hhZUE]
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query */ C/sDyv$
privateint beginIndex; |ULwUi-r
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/** The default constructor */ K% Gbl#
public Page(){ Sn_zhQxG
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} [;]@PKW?w
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/** construct the page by everyPage e 1k\:]6
* @param everyPage lQ}e"#<
* */ o}iqLe\
public Page(int everyPage){ =XT'D@q~W
this.everyPage = everyPage; [xVE0l*\
} $_.m<
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/** The whole constructor */ wq( m%F
public Page(boolean hasPrePage, boolean hasNextPage, 4cO||OsMU
/)ubyl]^p
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int everyPage, int totalPage, >VAZ^kgi
int currentPage, int beginIndex){ ? }k~>. \
this.hasPrePage = hasPrePage; 7 %P?3
this.hasNextPage = hasNextPage; h)M9Oup`
this.everyPage = everyPage; &<u
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this.totalPage = totalPage; L-ZJ[#D
this.currentPage = currentPage; \I\'c.$I.Y
this.beginIndex = beginIndex; ;5*)kX
} 9u 'hCi(
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/** lRn6Zh
* @return =](c7HEQf
* Returns the beginIndex. d E@R7yU@
*/ \bh3 &Z'.
publicint getBeginIndex(){ o3;u*f0rWn
return beginIndex; zr0_SCh;2
} ))n7.pB9/
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/** 1%L* 9>e
* @param beginIndex 3q:-98DT
* The beginIndex to set. dkV%Pyj
*/ !Xwp;P=
publicvoid setBeginIndex(int beginIndex){ /~_Cb=7
this.beginIndex = beginIndex; S?{|qlpy
} Q#@gOn=W\
[@}{sH(#Ta
/** JH~v e
* @return 6,'!z
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* Returns the currentPage. u.gh04{5
*/ eiZv|?^0
publicint getCurrentPage(){ AJrwl^lm
return currentPage; [Cz.K?+#M
} KJa?TwnC
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/** %PG::b
* @param currentPage ,q#^_/?
* The currentPage to set. 0EM`,?i .Q
*/ F9e$2J)C
publicvoid setCurrentPage(int currentPage){ XN"V{;OP1
this.currentPage = currentPage; jlER_I]
} NQ<~$+{
xZ@H{):
/** Y#PbC
* @return $JTy`g0>x
* Returns the everyPage. &Ko}Pv
*/ 0D>~uNcT}
publicint getEveryPage(){ DR9M8E
return everyPage; QEM")(
} RlX;c!K
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/** ?ZSG4La\
* @param everyPage lN+NhPF
* The everyPage to set. `sN3iD!@R
*/ n?pCMS|
publicvoid setEveryPage(int everyPage){ `h S<F"
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this.everyPage = everyPage; }se)=7d8
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} 76)(G/
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/** O6;>]/`
* @return ywk;
* Returns the hasNextPage. <_ */
*/ K 3&MR=#^
publicboolean getHasNextPage(){ X3]E8)645N
return hasNextPage; j&fr4t3
} mo#4jtCE
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/** Sct-,K%i
* @param hasNextPage ru(Xeojv#
* The hasNextPage to set. c ~YD|l
*/ g$dL5N7
publicvoid setHasNextPage(boolean hasNextPage){ KN~E9oGs
this.hasNextPage = hasNextPage; %8$JL=c
} X@9_ukdpu
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/** :c)<B@NqNo
* @return 35RH|ci&
* Returns the hasPrePage. tb/u@}")
*/ 'xStA
publicboolean getHasPrePage(){ Jkm\{;
return hasPrePage; ]vQo^nOo
} yc]ni.Hz
NFLmM
/** cw"x0 RS
* @param hasPrePage #A]7cMZ'W
* The hasPrePage to set. %/etoK
*/ 4C01=,6ye
publicvoid setHasPrePage(boolean hasPrePage){ (P`{0^O"}
this.hasPrePage = hasPrePage; m1F<L
} TWx<)
tO[+O=d
/** CM5A-R90
* @return Returns the totalPage. .[1A
* 9d[0i#` :q
*/ $Q{1^
publicint getTotalPage(){ 82J0t}:U
return totalPage; j&T/.]dX&
} QV .A.DK
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/** @/$mZ]|T
* @param totalPage _hh|/4(
* The totalPage to set. #mkr]K8A4
*/ g=U?{<8.m
publicvoid setTotalPage(int totalPage){ [7I|8
this.totalPage = totalPage; Jh466;
E
} m]"YR_
}(o/+H4
} J1R%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 U1q$B32
*|E@81s#
个PageUtil,负责对Page对象进行构造: )<^ ~${$U
java代码: }?fa+FQGp
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/*Created on 2005-4-14*/ vq5I 2
package org.flyware.util.page; qyJpm{
epG;=\f}m`
import org.apache.commons.logging.Log; qFs<s<]
import org.apache.commons.logging.LogFactory; XdS<51 C
GUp51*#XR
/** ,@!d%rL:4]
* @author Joa aZ0H)
* @B^'W'&C
*/ C|lMXp\*
publicclass PageUtil { ):|)/ZiC'
>u/yp[Ky
privatestaticfinal Log logger = LogFactory.getLog 7J;.T%4l
EV(/@kN2
(PageUtil.class); fZ376Z:S$
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/** 5Y&@
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* Use the origin page to create a new page mPD'"
* @param page )Z _i[1V
* @param totalRecords % (.PRRI
* @return W1!eY,1}
*/ aLq;a
publicstatic Page createPage(Page page, int +]e4c;`ko}
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totalRecords){ b;O+QRa
return createPage(page.getEveryPage(), nSC>x:jY5/
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page.getCurrentPage(), totalRecords); ^\6UTnS.
} bc"N
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/** V&nN/CF
* the basic page utils not including exception 4HHf3j!5
2X]\:<[4
handler '
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* @param everyPage eo8 0L
* @param currentPage Xo5L:(?K
* @param totalRecords Ii8jY_
* @return page [y:LA~q
*/ `Q hh{
publicstatic Page createPage(int everyPage, int ?l (hS\N,
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[
currentPage, int totalRecords){ {HU48v"W
everyPage = getEveryPage(everyPage); 9x1Dyz 2?F
currentPage = getCurrentPage(currentPage); re!CF8
q
int beginIndex = getBeginIndex(everyPage, DNy)\+[
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currentPage); 3IkG*enI
int totalPage = getTotalPage(everyPage, U_~~PCi
*+z({S_Nv
totalRecords); <*+MBF
boolean hasNextPage = hasNextPage(currentPage, Txh;r.1e
@RP|?Xc{?
totalPage); !jbjrzv9
boolean hasPrePage = hasPrePage(currentPage); }VGiT~2$
KOQTvJ_#
returnnew Page(hasPrePage, hasNextPage, %([c4el>\F
everyPage, totalPage, [ZbK)L+_
currentPage, ]*|K8&jxl
#o RUH8
beginIndex);
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} vn<S"
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privatestaticint getEveryPage(int everyPage){ UQ)}i7v
return everyPage == 0 ? 10 : everyPage; Kf4z*5Veqr
} DbN'b(+
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privatestaticint getCurrentPage(int currentPage){ E'G>'cW;x
return currentPage == 0 ? 1 : currentPage; dc)Gk
} ob{pQx7
:m\KQ1sq
privatestaticint getBeginIndex(int everyPage, int Xd6y7s
q*OKA5
currentPage){ '}u31V"SS
return(currentPage - 1) * everyPage; Q\76jD`m\
} b nGA.b
^U}0D^jDeE
privatestaticint getTotalPage(int everyPage, int Ub,unU
P `"7m-
totalRecords){ Pcs@`&}7r
int totalPage = 0; /Hmo!"W`
3p4?-Dd|_$
if(totalRecords % everyPage == 0) o3=kF
totalPage = totalRecords / everyPage; u*{ _WL[(
else }El_.@'T &
totalPage = totalRecords / everyPage + 1 ; ,X^_w
g
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return totalPage; AX+d? M
} [JoTWouNU
UD{/L"GG
privatestaticboolean hasPrePage(int currentPage){ w|C~{
return currentPage == 1 ? false : true; =]e^8;e9
} >U?Bka!
h>:RCpC
privatestaticboolean hasNextPage(int currentPage, (, "E9.
.h,xBT`}Ji
int totalPage){ Q=E@i9c9
return currentPage == totalPage || totalPage == 9eiBj
OU@x1G{Cy
0 ? false : true; 2(Uz9!<V
} =joXP$n^
Bq@wS\W>b}
\F~Cbj+'Nu
} r%d11[z
YS~t d+*
"Q{~Bj~
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1 ],,
Ar5
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。
'*u;:[73
,hLSRj{
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 !"%sp6Wc
v&2@<I>
做法如下: ;bZ*6-\!-
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 PMs_K"-K
Z&jb,eh2
的信息,和一个结果集List: x}'4^Cv
java代码: wg<|@z5
g)qnjeSs]
vUe
*
/*Created on 2005-6-13*/ {$YD-bqY
package com.adt.bo; s}9tK(4v
F*t_lN5{
import java.util.List; ([b!$o<v
'h>5&=r
import org.flyware.util.page.Page; 9zYiG3 d
zL`uiZl
/** @[tV_Z%,b
* @author Joa Yc`j
*/ F(9
Y/UXH
publicclass Result { DnsP7k.8T
OP`Jc$|6
private Page page; ~+ s*\~
|( 9#vt#
private List content; zX [r
F] ?@X
/** RB7AI!'a?
* The default constructor dIpW!Pj^
*/ Yz-JI=
public Result(){ uO@3vY',n
super(); Ocwp]Mut&
}
1Dya?}3
^M"z1B]
/** q7f;ZK=f
* The constructor using fields M&/aJRBS
* 'K`Rbhy
* @param page &49$hF
g6"
* @param content #3K,V8(
*/ qJ+52U|z
public Result(Page page, List content){ "WbVCT'i
this.page = page; Kka8cG
this.content = content; @>fO;*
} H8$<HhuZM
\}Acq;
/** o9Txo
(tYU
* @return Returns the content. f-3'D-{EKt
*/ n(1wdl Ep
publicList getContent(){ tpa^k
return content; zn
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} !/6\m!e|1R
Yn4)Zhkk
/** |ck
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* @return Returns the page. (7;J"2M
*/ #~4{`]W6
public Page getPage(){ ~mK-8U4>K,
return page; %l:|2s:
} Du^x=;
n</k/Mk}
/** 5:%..e`T
* @param content ZD)0P=%
* The content to set. au~]
*/ XLZ j
public void setContent(List content){ <mZrR3v'D
this.content = content; U=F-]lD
} lk_s!<ni
w|}W(=#
/** #9$V
08
* @param page M|UxE/
* The page to set. 8
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*/ HDF"]l;
publicvoid setPage(Page page){ `6Ureui2?
this.page = page; xd^&_P$=
} 5pRY&6So
} vuR5}/Ev
TBZ-17+
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Z|ZBKcmg
{sC@N![
2. 编写业务逻辑接口,并实现它(UserManager, Ap]4QqU
dD/t_ {h
UserManagerImpl) w"cM<Ewu
java代码: )=jT_?9b
.pZ o(*
Y*@|My`
/*Created on 2005-7-15*/ m|]j'g?{}(
package com.adt.service; /Hv*K&}M
Hp\Ddx >Jd
import net.sf.hibernate.HibernateException; <ROpuY\!l
XzT78
import org.flyware.util.page.Page; `$S^E !=
},DyU
import com.adt.bo.Result; 2)wAFO6u
f.||PH
/** S:ls[9G[3
* @author Joa +0]'| t F>
*/ TdQ]G2
publicinterface UserManager { Bv^+d\*1
=G(*gx
public Result listUser(Page page)throws ^8:VWJM
R
N@^j
HibernateException; 9C_*3?6
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} \a"i7Caa
VCjq3/[_
RI-A"cc6A
wW-A b
&K>cW$h=a
java代码: {AOG"T&<
bFg*l$`5
0<g<GQ(E
/*Created on 2005-7-15*/ #+9rjq:v#]
package com.adt.service.impl; *C\(wL
lW
p~t
import java.util.List; !\^jt%e&
n@
4@,
import net.sf.hibernate.HibernateException; XYe~G@Q Z
Jen%}\
import org.flyware.util.page.Page; :X_CFW
import org.flyware.util.page.PageUtil; 1Ao6y.S
|zq4* 5
import com.adt.bo.Result; ]ni6p&b>
import com.adt.dao.UserDAO; r}
Lb3`'
import com.adt.exception.ObjectNotFoundException; @lS==O-`f
import com.adt.service.UserManager; ;o[rQ6+
FEF"\O|Q
/** f ba&`
* @author Joa pz7H To;p
*/ !EOQhh
publicclass UserManagerImpl implements UserManager { Yt+h2ft!
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F+
private UserDAO userDAO; >SoO4i8
O|I+],
/** /Pvk),ca
* @param userDAO The userDAO to set. f2yq8/J8.
*/ gfde#T)S
publicvoid setUserDAO(UserDAO userDAO){ 7X}TB\N1
this.userDAO = userDAO; jH>8bXQqZ
} J!hFN]M<<
qbiK^gR
/* (non-Javadoc) KlN/\N\
* @see com.adt.service.UserManager#listUser Fu7M0X'p
YLOwQj'
(org.flyware.util.page.Page) s\gp5MT
*/ N}b^fTq
public Result listUser(Page page)throws {,?ss$L
o0ZBi|U\4
HibernateException, ObjectNotFoundException { qsI^oBD"
int totalRecords = userDAO.getUserCount(); *}cSE|S%
if(totalRecords == 0) +j{Y,t{4
throw new ObjectNotFoundException
l{$[}<
FI"HJwAs
("userNotExist"); +ZA)/
page = PageUtil.createPage(page, totalRecords); 53Yxz3v
List users = userDAO.getUserByPage(page); $wV1*$1NM
returnnew Result(page, users); /=)L_
} m\ S\3n
19c@ `?
} FW..mD9)}
B=n[)"5fBO
s5D:
])w[
BT,b-=
;J-
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 8 #}D
:(
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询,接下来编写UserDAO的代码: FhkkWWL
3. UserDAO 和 UserDAOImpl: 'yY>as
java代码: ]~0}=,H$N
!GwL,)0@^
/,s[#J
/*Created on 2005-7-15*/ 6C [E
package com.adt.dao; V'G Ju
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import java.util.List; 9Uf j
i47j lyH
import org.flyware.util.page.Page; ;H'gT+t<c
d5`3wd]]'v
import net.sf.hibernate.HibernateException; ^T::-pN*
g%[c<l9
/** 0Hxmm@X2
* @author Joa T .FI'wy
*/ !%)F J:p
publicinterface UserDAO extends BaseDAO { %Dg0fL
ZyrI R
publicList getUserByName(String name)throws 4d b(<h
@a:>$t
HibernateException; .mLK`c6
eqw0]U\pv
publicint getUserCount()throws HibernateException; +ZM)bbB
hCjR&ZA
publicList getUserByPage(Page page)throws y){
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x^4xq#Bb7
HibernateException; npJt3
Y_I
/='. 4v
} d)4
m6
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Qham^
1cS}J:0P
VCXJwVb
java代码: <Ln1pV~k
u/cg|]x&T
EkgE_8
/*Created on 2005-7-15*/ #wL
package com.adt.dao.impl; 35E _W>n
h%}/Cmx[
import java.util.List; [<DZ*|+
%3NqSiMs
import org.flyware.util.page.Page; 3;S,3
8!Vl
import net.sf.hibernate.HibernateException; +qh[N@F
import net.sf.hibernate.Query; oE#d,Z
r E}%KsZ
import com.adt.dao.UserDAO; WI?oSE w
4"gM<z
/** ne4Q#P
* @author Joa 6d_'4B
*/ S30?VG9U0f
public class UserDAOImpl extends BaseDAOHibernateImpl U2bjFLd"
*:ZDd
implements UserDAO { !%"8|)CAr
.Fdgb4>BXX
/* (non-Javadoc) xuqv6b.
* @see com.adt.dao.UserDAO#getUserByName $0vb^
o4|M0
(java.lang.String) W[Ls|<Q
*/ 6@rMtQfI
publicList getUserByName(String name)throws "rx-_uK*
5H*\t 7
HibernateException { 9I6a"PGDb
String querySentence = "FROM user in class :]\([Q+a
:Zlwp6
com.adt.po.User WHERE user.name=:name"; .&DhN#EN0
Query query = getSession().createQuery r"P|dlV-
Wk)OkIFR
(querySentence); 0*f)=Q'
query.setParameter("name", name); x[a<mk
return query.list(); 6}d.5^7lr
} uScMn/%
OX\A|$GS
/* (non-Javadoc) kqFP)!37
* @see com.adt.dao.UserDAO#getUserCount() f|\onHI)>
*/ %J+E/
publicint getUserCount()throws HibernateException { <g"{Wv: h
int count = 0; SLa>7`<Q
String querySentence = "SELECT count(*) FROM U~:-roQ(\
4 o Fel.o
user in class com.adt.po.User"; U/!TKic+
Query query = getSession().createQuery =vX/{C
'uBu6G
(querySentence); h2G$@8t}I
count = ((Integer)query.iterate().next PvPOU"
GPN]9
()).intValue(); t'n pG}`tE
return count; e"|efE
} `sn^ysp
'=b/6@&
/* (non-Javadoc) Z?h~{Mg
* @see com.adt.dao.UserDAO#getUserByPage IxY|>5z
!|^|,"A)
(org.flyware.util.page.Page) ,o86}6Ag
*/ k\5c|Wq|g
publicList getUserByPage(Page page)throws Hj^1or3R]
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HibernateException { (A9Fhun
String querySentence = "FROM user in class <^#,_o,!
TM%|'^)
com.adt.po.User";
akp-zn&je
Query query = getSession().createQuery 9X}10u:
I|qo+u)
(querySentence); hOjk3
k
query.setFirstResult(page.getBeginIndex()) -r`.#c4
.setMaxResults(page.getEveryPage()); Tp?7_}tRi
return query.list(); M\uiq38
} J,'M4O\S
/:m->
T
} (KjoSN(
K
<? q?Mn
5-:?&|JK;
@LF,O}[2J
G#ZH.24Y
至此,一个完整的分页程序完成。前台的只需要调用 )|ju~qbf
8{^kQ/]'|
userManager.listUser(page)即可得到一个Page对象和结果集对象 kMIcK4.MH
G/)O@Ugp
的综合体,而传入的参数page对象则可以由前台传入,如果用 D+TD 95t
3#3n!(
webwork,甚至可以直接在配置文件中指定。 ^UP`%egR
r8`ffH
下面给出一个webwork调用示例: @ a! #G
java代码: KI"#f$2&
`KZm0d{H
hNC&T`.-~B
/*Created on 2005-6-17*/ 8I =2lK
package com.adt.action.user; `'DmDg
5%Y3 Kwyy
import java.util.List; .YtKS
; 5*&xz
import org.apache.commons.logging.Log; !z\h|wU+
import org.apache.commons.logging.LogFactory; ">\?&0
import org.flyware.util.page.Page; T^zXt?
sA+ }TNhq
import com.adt.bo.Result; aC]$k'71
import com.adt.service.UserService; {i;r
import com.opensymphony.xwork.Action; u+9hL4
)HEa<P^kJl
/** /ixp&Z|7
* @author Joa "BM#4
*/ nGC/R&
publicclass ListUser implementsAction{ /p/]t,-j2
_P!m%34|
privatestaticfinal Log logger = LogFactory.getLog tR#OjkvX
2R[:]-b
(ListUser.class); $zUP?Gq!
%Tfbsyf%f
private UserService userService; bTI|F]^!
C"y(5U)d
private Page page; 1y:-N6
CT&|QH{
privateList users; Pd8![Z3
0-B5`=yU
/* y5vvu>nd
* (non-Javadoc) R!HXhQ
* QFA8N
* @see com.opensymphony.xwork.Action#execute() v_yw@
*/ _5w]a 2
publicString execute()throwsException{ ez7A4>/
Result result = userService.listUser(page); (O\)_#-D
page = result.getPage(); _?nL+\'V
users = result.getContent(); A@`}c,G
return SUCCESS; VMZMG$C
} Z*F3G#A
pd?Mf=>#
/** HVRZ[Y<^
* @return Returns the page. &s(^@OayE
*/ -uS!\
public Page getPage(){ Zj(AJ* r
return page; h0EEpL|\
} 5%"V[lDx@
]U+LJOb
/** /'SNw?&
* @return Returns the users. +w`2kv
*/ y
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publicList getUsers(){ PrqlTT}Px
return users;
l]5KN
} ,~U>'&M;
-OV&Md:~
/** 6jaEv#
* @param page {p2!|A&a
* The page to set. g _9C*
*/ FaAC&F@u
publicvoid setPage(Page page){ \
#F
this.page = page; [g|_~h
} iI T;K@&
M/f<A$xx_
/** %uDi#x.
* @param users { l/U6](
* The users to set. .^`{1%
*/ (MM]N=Tw4
publicvoid setUsers(List users){ [(i
this.users = users; LBeF&sb6
} >58YjLXb
j^sg6.Z*
/** LH.]DVj
* @param userService tAd%#:K
* The userService to set. LVM%"sd?
*/ d0!5j
publicvoid setUserService(UserService userService){ RMV/&85?y
this.userService = userService; C^Yb\N}S
} ^LnTOdAE
} tU5zF.%
gx/,)> E.
Wtd/=gmiI
&J]K3w1p
QO:!p5^:
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, lN)C2 2
F~vuM$+d
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 tKuwpT1Qc
q[_VuA]&
么只需要: Dj?> <@
java代码: HyQJXw?A:
@gEUm_#HTs
x8B}ZIbT9
<?xml version="1.0"?> 5V~oIL
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork &m7]v,&
wU36sCo
1.0//EN" "http://www.opensymphony.com/xwork/xwork- <NY^M!
p`dU2gV
1.0.dtd"> ys^oG$lq
&BLJT9Frx
<xwork> H|<[YYk
:S83vE81WK
<package name="user" extends="webwork- RLXL&
4Z=_,#h4.
interceptors"> Rok7n1gW
Jt<_zn_FG
<!-- The default interceptor stack name HRCT}
xt*
3'v
--> ~W'{p
<default-interceptor-ref f}ji?p
d"mkL-
name="myDefaultWebStack"/> pj{`';
:g
SM#]H-3
<action name="listUser" 4he GnMD
T*Exs|N2P-
class="com.adt.action.user.ListUser"> u%KTNa0
<param ~H_/zK6e
TER=*"!
name="page.everyPage">10</param> [ ({nj`
<result
(N6i4
g6
^7cGq+t
name="success">/user/user_list.jsp</result> [PM2\#K
</action> <z&/L/bl"
N^G
Mp,8
</package> qJs<#MQ2
wu!59pL
</xwork> iN\4gQ!
LgU_LcoM*
orpri O|qD
`pa!~|p
iRbT/cc{
{SPq$B_VR
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 z+wA
rPxc
ItVWO:x&v
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。 / }X1W
-H@:*
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 81F/G5
z"L/G
DB|Y
~9]hV7y5C
3?9IJ5p
我写的一个用于分页的类,用了泛型了,hoho rig,mv
&< `N T D
java代码: *uf'zQ<9
Ad8n<zt|
$E~`\o%Ev
package com.intokr.util; &*,#5.
cWaSn7p !X
import java.util.List; XGWSdPJLr
Y|f[bw
/** @7]yl&LZ
* 用于分页的类<br> u@UMP@"#
* 可以用于传递查询的结果也可以用于传送查询的参数<br> kk@fL
* SI-q C
* @version 0.01 vhW2PzHFRi
* @author cheng R6 .hA_ih
*/ O!#g<`r{K
public class Paginator<E> { 2B[X,rL.pX
privateint count = 0; // 总记录数 ?m}s4a
privateint p = 1; // 页编号 TH&U
j1
privateint num = 20; // 每页的记录数 `l
^9/_g'6
privateList<E> results = null; // 结果 1>_8d"<Gd
Fn;SF4KOm
/** gnOt+W8
* 结果总数 8,4"uuI
*/ mbTEp*H
publicint getCount(){ rdP[<Y9
return count; 5y[Oj^
} Eqd<