Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 CA'hvXb.
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 K1CMLX]m
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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 xy2eJJq
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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 tVK?VNW
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。 *T1L)Cp
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分页支持类: k B$lkl\C
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java代码: Y>c5:F;
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package com.javaeye.common.util; :z}~U3,JE
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import java.util.List; B]CS2LEqh
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publicclass PaginationSupport { *m2d#f
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publicfinalstaticint PAGESIZE = 30; #<^/yoH7C6
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privateint pageSize = PAGESIZE; M}{n6T6B
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privateList items; C: TuC5Sr
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privateint totalCount; .XZ 71E
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privateint[] indexes = newint[0]; 7zi^{]
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privateint startIndex = 0; yS(=eB_
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public PaginationSupport(List items, int c>%z)uY>/
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totalCount){ /61ag9pN
setPageSize(PAGESIZE); RJ7/I/yD|
setTotalCount(totalCount); rmAP&Gw I
setItems(items); 1L(Nfkh
setStartIndex(0); bTI&#Hu
} !~VR|n-
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public PaginationSupport(List items, int ~Y}Z4" o
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totalCount, int startIndex){
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setPageSize(PAGESIZE); P,LXZ
setTotalCount(totalCount); I NFzX
setItems(items); ph5xW<VNP
setStartIndex(startIndex); {jCu9 ]c!
} B_6v'=7]
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public PaginationSupport(List items, int 6='_+{
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totalCount, int pageSize, int startIndex){ N:sECGS,
setPageSize(pageSize); Z"PDOwj5
setTotalCount(totalCount); |M0,%~Kt
setItems(items); h)aWerzL
setStartIndex(startIndex); OQX{<pQ6
} 9#.NPfMF
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publicList getItems(){ ^me}k{x
return items; b{ubp
} S|Ij q3
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publicvoid setItems(List items){ 2TevdyI
this.items = items; Cvu8X&y
} +A&IxsTq5=
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publicint getPageSize(){ Dk.9&9mz
return pageSize; xN":2qy#T
} au9Wo<mR
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publicvoid setPageSize(int pageSize){ *<h
this.pageSize = pageSize; <8xP-(wk;
} McMK|_H
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publicint getTotalCount(){ Aj)<8
return totalCount; }Rf:DmPE
} QYCNO#*
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publicvoid setTotalCount(int totalCount){ BIB>U W
if(totalCount > 0){ [laL6
this.totalCount = totalCount; WRU@i;l
int count = totalCount / MjF.>4
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pageSize; C">=2OO
if(totalCount % pageSize > 0) =-B3vd:LF
count++; :4L5@>b-
indexes = newint[count]; ztxQv5=:,
for(int i = 0; i < count; i++){ FlA$ G3
indexes = pageSize * ![MDmt5Ub^
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i; N#6A>
} xuH<=-O>ki
}else{ gQcr'[[a
this.totalCount = 0; Qak@~b
} F|3FvxA
} z$im4'\c
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publicint[] getIndexes(){ *fy`JC
return indexes; {G*:N[pJp
} S:GUR6g8D
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publicvoid setIndexes(int[] indexes){ R?e7#HsJ
this.indexes = indexes; MBTt'6M
} Exo`Z`m`U
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publicint getStartIndex(){ 7g<`wLAH
return startIndex; {XUfxNDf
} xo"4mbTV
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publicvoid setStartIndex(int startIndex){ e hB1`%@
if(totalCount <= 0) ~ !+h"%'t
this.startIndex = 0; `"-!UkD+
elseif(startIndex >= totalCount) D;8V{Hs
this.startIndex = indexes o>,z %+
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[indexes.length - 1]; 4R^j"x
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elseif(startIndex < 0) eR
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this.startIndex = 0; ?b' '
else{ q,>F#A'
this.startIndex = indexes zinl.8Uk
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[startIndex / pageSize]; Da[X
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} jW0z|jr
} )mO;l/,0
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publicint getNextIndex(){ J?ZVzKTb>}
int nextIndex = getStartIndex() + p$G3r0@
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pageSize; z4`n%~w1b
if(nextIndex >= totalCount) vo<#sa^,j
return getStartIndex(); l@F
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else Wn#JYp
return nextIndex; A,[m=9V
} l6U'
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publicint getPreviousIndex(){ =F-^RnO%\
int previousIndex = getStartIndex() - @"7dk.|
*TI6Z$b|6
pageSize; pXlBKJmW
if(previousIndex < 0) d7zE8)D U7
return0; ~:b~f]lO
else Y9ce"*b
return previousIndex; ojqX#>0K
} `B0*/ml
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} Sf:lN4
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抽象业务类 m Dq,,
java代码: 8~+Msn:
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/** bu5)~|?{t
* Created on 2005-7-12 sb5kexGxkc
*/ [B<{3*R_
package com.javaeye.common.business; KePHn:c
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import java.io.Serializable; Z|wDM^Lf
import java.util.List; "n-xsAG
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import org.hibernate.Criteria; '(>N
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import org.hibernate.HibernateException; >Cc$ P
import org.hibernate.Session; NFPkK?+
import org.hibernate.criterion.DetachedCriteria; 9K(b Z{
import org.hibernate.criterion.Projections; qT%E[qDS
import u%'22q$
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org.springframework.orm.hibernate3.HibernateCallback; 8Qy |;T}
import qm_E/B
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org.springframework.orm.hibernate3.support.HibernateDaoS /UAj]U
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upport; GMI>$$<
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import com.javaeye.common.util.PaginationSupport; $6Psq=|
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public abstract class AbstractManager extends h|Qh/jCX
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HibernateDaoSupport { Wc[)mYOSuO
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privateboolean cacheQueries = false; Ce emR>\t
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rl3=5{
privateString queryCacheRegion; T]k@g_
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publicvoid setCacheQueries(boolean ``D-pnKK
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cacheQueries){ pTd@i1%Nr
this.cacheQueries = cacheQueries; i ib-\j4d
} d4tVK0
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publicvoid setQueryCacheRegion(String <L0_<T
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queryCacheRegion){ 3]A'C&
this.queryCacheRegion = p};<l@
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queryCacheRegion; XZJx3!~fm
} 5@\<:Zmi
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publicvoid save(finalObject entity){ EY(4<;)
getHibernateTemplate().save(entity); NKN!X/P
} Ns{4BM6j
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publicvoid persist(finalObject entity){ |/ Z4lcI
getHibernateTemplate().save(entity); lU3wIB
} u5,<.#EVY
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publicvoid update(finalObject entity){ _Yv9u'q"
getHibernateTemplate().update(entity); J<D =\
} 3@ SfCG&|e
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publicvoid delete(finalObject entity){ 4l:+>U@KU
getHibernateTemplate().delete(entity); w@R-@
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} W%x#ps5%
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publicObject load(finalClass entity, 5NK:94&JE
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finalSerializable id){ 7O j9~3o4
return getHibernateTemplate().load z;)% i f6
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(entity, id); l\)Q3.w
} LBzpaLd
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publicObject get(finalClass entity, ~Km8-b(&
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finalSerializable id){ a&JAF?k
return getHibernateTemplate().get 0nX5
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(entity, id); gxiJ`.D=
} 2]l*{l^ Bl
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publicList findAll(finalClass entity){ f/xBR"'
return getHibernateTemplate().find("from |?8wyP
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" + entity.getName()); BC^WPr
} lsd\ `X5,
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publicList findByNamedQuery(finalString QLn5:&
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namedQuery){ Sq,x@
return getHibernateTemplate .%o:kq@B
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().findByNamedQuery(namedQuery); 8LOzL,Ah
} 94+#6jd e
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publicList findByNamedQuery(finalString query, )+J?(&6
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finalObject parameter){ 15B$Sp!/`e
return getHibernateTemplate ZD*>i=S
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().findByNamedQuery(query, parameter); Gl+}]Vn[n
} $JOIK9+3z#
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publicList findByNamedQuery(finalString query, X^?-Une
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finalObject[] parameters){ *i|hcDk
return getHibernateTemplate W`KkuQ4cM
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().findByNamedQuery(query, parameters); qsLsyi |zG
} WH!<Z=#c}
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publicList find(finalString query){ h<uQ~CQg
return getHibernateTemplate().find R!`#pklB
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(query); .Xr_BJ _
} {\k9%2V*+
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publicList find(finalString query, finalObject ~"(1~7_
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parameter){ N24+P5
return getHibernateTemplate().find ]HRE-g
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(query, parameter); iS{)Tll}&
} 1oC/W?l^
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public PaginationSupport findPageByCriteria Z|)~2[Roa
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(final DetachedCriteria detachedCriteria){ wM><DrQ
return findPageByCriteria =w8*n2
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); wH<S0vl
} n_5g:`Y
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public PaginationSupport findPageByCriteria bf3)^ 49}
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(final DetachedCriteria detachedCriteria, finalint #df Aqg'
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startIndex){ &c A?|(7-
return findPageByCriteria u*"tZ+|m
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(detachedCriteria, PaginationSupport.PAGESIZE, UHXlBH@
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startIndex); :QN,T3i'/3
} \4V'NTjB
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public PaginationSupport findPageByCriteria @NO&3m]
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(final DetachedCriteria detachedCriteria, finalint iud%X51
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pageSize, fY>\VY$>
finalint startIndex){ I@.qon2V
return(PaginationSupport) KExfa4W 3{
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getHibernateTemplate().execute(new HibernateCallback(){ z8A`BVqI
publicObject doInHibernate 6~^+</?
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(Session session)throws HibernateException { =uD2j9!"7
Criteria criteria = $WdZAv\_S
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detachedCriteria.getExecutableCriteria(session); `9@!"p
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int totalCount = LV`- eW
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((Integer) criteria.setProjection(Projections.rowCount JG4Tb{F=
T
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()).uniqueResult()).intValue(); a29mVmi >
criteria.setProjection 9gjx!t>`H
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(null); XfB;^y=u8
List items = 2 !{P<
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criteria.setFirstResult(startIndex).setMaxResults qD2<-E&M/
<{e0i
(pageSize).list(); %R(j|a9z
PaginationSupport ps = |
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new PaginationSupport(items, totalCount, pageSize, UUX
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startIndex); DT_012z
return ps; x!S8'
} 10*U2FY)]
}, true); nQ8EV>j2
} =_=jXWOQv
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public List findAllByCriteria(final >4bOM@[]
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DetachedCriteria detachedCriteria){ #[J..i/h
return(List) getHibernateTemplate K{HdqmxL.I
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().execute(new HibernateCallback(){ @Yy=HV
publicObject doInHibernate [4"%NY
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(Session session)throws HibernateException { 2_U H, n
Criteria criteria = ?jy^WF`
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detachedCriteria.getExecutableCriteria(session); ~ 5`Ngpp
return criteria.list(); YAsvw\iseK
} )\p@E3Uxf
}, true);
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} AlGD .K
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public int getCountByCriteria(final owQLAV
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DetachedCriteria detachedCriteria){ vrh}X[JEw'
Integer count = (Integer) 0p![&O
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getHibernateTemplate().execute(new HibernateCallback(){ |qfnbi-\
publicObject doInHibernate i9w xP i
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(Session session)throws HibernateException { Q TM+WD
Criteria criteria = ;sb0,2YyP
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detachedCriteria.getExecutableCriteria(session); 8&H1w9NrX_
return jt;68SA
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criteria.setProjection(Projections.rowCount bSBI[S
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()).uniqueResult(); CEt_wKzf
} E/Y.f
}, true); wHdq :,0-!
return count.intValue(); 0W#.$X5
} e(j"u;=
} iQS?LksQX
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用户在web层构造查询条件detachedCriteria,和可选的 vP?"MG
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 %5jxq9:K
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PaginationSupport的实例ps。 kVZ>Dc2M
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ps.getItems()得到已分页好的结果集 V<P@hAAr
ps.getIndexes()得到分页索引的数组 KG)Y{-Ao
ps.getTotalCount()得到总结果数 *T*MLD]Q
ps.getStartIndex()当前分页索引 H|==i2V{
ps.getNextIndex()下一页索引 ]'MLy#9
ps.getPreviousIndex()上一页索引 *(s)CWf
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 AgO:"'c
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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 M {_`X
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一下代码重构了。 @I#@%"AW
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我把原本我的做法也提供出来供大家讨论吧: MX6;ww
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首先,为了实现分页查询,我封装了一个Page类: O>)8< yi$
java代码: &PgbFy
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/*Created on 2005-4-14*/ ;&?NuK
package org.flyware.util.page; Q_qc_IcM y
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/**
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* @author Joa 9Jaek_A`
* X{<j%PdC
*/ OV Iu&6#
publicclass Page { p7Gs
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/** imply if the page has previous page */ IgQW 5E#
privateboolean hasPrePage; !$f@j6.
m?>$!B4jFB
/** imply if the page has next page */ ES<"YF
privateboolean hasNextPage; bY&s$Ry3"
#*1\h=bzmW
/** the number of every page */ i{
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privateint everyPage; dGTAZ(1W
7[ *,t
/** the total page number */ 0:Ak4L6k
privateint totalPage; fLxFF
7-Fh!=\f/
/** the number of current page */ iVREkZ2SC
privateint currentPage; /DJyNf*
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/** the begin index of the records by the current bxK1v7
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query */ }`\+_@w
privateint beginIndex; gNo.&G [
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/** The default constructor */ BoHMz/DB
public Page(){ iw12x:
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} J}nE,U2
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/** construct the page by everyPage xW#r)aN]p
* @param everyPage 2_R'Kl![
* */ N? ky2wG
public Page(int everyPage){ q;InFV3rv
this.everyPage = everyPage; wBA[L}
} 9Psy$
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/** The whole constructor */ htq#( M
public Page(boolean hasPrePage, boolean hasNextPage, 1#&*xF"
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int everyPage, int totalPage, w`UB_h#Bl
int currentPage, int beginIndex){ Tmg~ZI:MW
this.hasPrePage = hasPrePage; =ugxPgn
this.hasNextPage = hasNextPage; RL[?&L$7^%
this.everyPage = everyPage; ?sdVd
this.totalPage = totalPage; tz6d}$
this.currentPage = currentPage; x3MV"hm2
this.beginIndex = beginIndex; )R<hYd
} gV91=Pj
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/** O)kC[e4
* @return ~Q0gSazXFt
* Returns the beginIndex. CZS{^6Ye
*/ Z1wN+Y.CA
publicint getBeginIndex(){ }`{aeVHT
return beginIndex; ?
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} \8'fy\
e #>wv]V
/** /0uZ(F|>I
* @param beginIndex #e((F,1z
* The beginIndex to set. Mp:tcy,*
*/ ^^qB=N[';
publicvoid setBeginIndex(int beginIndex){ H$9--p
this.beginIndex = beginIndex; NU-({dGK}
} 9_n!.zA<
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/** |-bSoq7t
* @return cP''
* Returns the currentPage. >t<FG2
*/ c8v+eyn
publicint getCurrentPage(){ IX7<
return currentPage; P%]li`56-c
}
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/** ]2T =%(*
* @param currentPage @V
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* The currentPage to set. ]!E|5=q
*/ ^z-e"
publicvoid setCurrentPage(int currentPage){ hw:zak#j,
this.currentPage = currentPage; 559znM=
} -n?}L#4%8
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/** RX P 0
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* @return (Eq0 |"cj
* Returns the everyPage. \Azl6`Em
*/
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publicint getEveryPage(){ %=xR$<D
return everyPage; o$FqMRep
} UN>!#Ji:$
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/** +R@5e+auQ.
* @param everyPage K'+GK S7.
* The everyPage to set. *Em 9R
*/ ? "]fGp6y
publicvoid setEveryPage(int everyPage){ Jtnuo]{R
this.everyPage = everyPage; Uc/MPCqZ
} 'j6PL;~c
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/** 8l-+
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* @return j(HC^\Hi
* Returns the hasNextPage. (D]l/akP
*/ Q/o!&&
publicboolean getHasNextPage(){ Z"<aS&GH
return hasNextPage; Q* ifmnB'
} JEL=,0J
DBANq\
/** 9->E$W
* @param hasNextPage ;Oh4W<hH}
* The hasNextPage to set. ,R5NKWo
*/ <7fF9X
publicvoid setHasNextPage(boolean hasNextPage){ ]1>U@oK
this.hasNextPage = hasNextPage; % <
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} J?&lpsB3_l
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/** Ml1yk)3G
* @return 8aQ\Yx
* Returns the hasPrePage. >Ip>x!wi
*/
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publicboolean getHasPrePage(){ {y0#(8-&
return hasPrePage; p:U9#(v)
} KY9sa/xO
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/** F/sXr(7
* @param hasPrePage jFf2( AR
* The hasPrePage to set. ( >zXapb2
*/ qMD 6LWJ
publicvoid setHasPrePage(boolean hasPrePage){ -(V]knIF
this.hasPrePage = hasPrePage; pV]m6!y&
} fEf",{I
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/** {|=
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* @return Returns the totalPage.
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* mO;X>~K
*/ t<mT=(zt*
publicint getTotalPage(){ t$^1A1Ef
return totalPage; Z[<rz6%cB
} ,rVm81-2
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/** 'yxRz5
* @param totalPage Is&z~Xy/
* The totalPage to set. I9O!CQCTt
*/ L!s/0kBg
publicvoid setTotalPage(int totalPage){ ,R]hNjs-{
this.totalPage = totalPage; S G|``}OA
} Tu2BQ4\[
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} WW82=2rJ9
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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 YzJ\< tkp
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个PageUtil,负责对Page对象进行构造: L"6qS3 [=
java代码: W}p>jP}
1^ZQXUzl%i
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/*Created on 2005-4-14*/ :c3}J<Z
package org.flyware.util.page; Nv}'"V>
^vmT=f;TM
import org.apache.commons.logging.Log; F!OVx<
import org.apache.commons.logging.LogFactory; S'm&Ll2i@
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/** a]XQM$T$
* @author Joa c+chwU0W
* t &XH:w&j
*/
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publicclass PageUtil { IH8^ fyQ`
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privatestaticfinal Log logger = LogFactory.getLog !N:!x[5
g]?&qF}
(PageUtil.class);
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x
LR
2H>B}
/** k4r;t: O ^
* Use the origin page to create a new page |;3Ru vX?+
* @param page KLD)h,]
* @param totalRecords `_Iy8rv:P
* @return 17g\XC@ Cl
*/ OCmF/B_
publicstatic Page createPage(Page page, int \ cmt'b
P @N7g`u3}
totalRecords){ d#E]>:w9
return createPage(page.getEveryPage(), ;BzbWvBo
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page.getCurrentPage(), totalRecords); 1FCqkwq[
} )N h67P3X"
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/** eaLSq
* the basic page utils not including exception &5>R>rnB
*ub]M3O
handler Tbv", b
* @param everyPage >PdYQDyVS
* @param currentPage 8OE=7PK
* @param totalRecords [@d$XC]Qz
* @return page K P{|xQ>
*/ B1dVHz#
publicstatic Page createPage(int everyPage, int ~ED8]*H|`
;|_aACina
currentPage, int totalRecords){ 3aIP^I1
everyPage = getEveryPage(everyPage); Y"~Tf{8
currentPage = getCurrentPage(currentPage); j9"uxw@
int beginIndex = getBeginIndex(everyPage, e0iE6:i
(
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currentPage); R~OameRR
int totalPage = getTotalPage(everyPage, {(;dHF%{
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totalRecords); LVNq@,s
boolean hasNextPage = hasNextPage(currentPage, j\l9|vpp
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totalPage); &4 Py
boolean hasPrePage = hasPrePage(currentPage); / blVm1F
7PQ03dtfg
returnnew Page(hasPrePage, hasNextPage, 9gP-//L@
everyPage, totalPage, +>3XJlZV
currentPage, |iN!V3#S
:lj1[q:Y>
beginIndex); '&/ 35d9|*
} O[ tD7!1
htC~BK3(
privatestaticint getEveryPage(int everyPage){ ^Ud1 ag!-
return everyPage == 0 ? 10 : everyPage; \a\-hm
} Co[fq3iX#
"f^s*I
privatestaticint getCurrentPage(int currentPage){ K.3)m]dCl
return currentPage == 0 ? 1 : currentPage; %:i; eUKR
} 2fZVBj
M-inlZNR
privatestaticint getBeginIndex(int everyPage, int XaT9`L<
)~/;Xl#b-
currentPage){ 0>@D{_}s
return(currentPage - 1) * everyPage; V1y"
} lAjP'(
ffMh2
privatestaticint getTotalPage(int everyPage, int _}MO.&Y
=eG?O7z&
totalRecords){ DmDsn
int totalPage = 0; hM}rf6B
QTZfe<m0
if(totalRecords % everyPage == 0) *12,MO>go
totalPage = totalRecords / everyPage; %`*`HU#X
else R^8L^8EL
totalPage = totalRecords / everyPage + 1 ; P<<?7_ ??
M "QT(u+
return totalPage; Uc
oVp}vl
} kLc}a5;
%eJolztKZ
privatestaticboolean hasPrePage(int currentPage){ `PML4P[
return currentPage == 1 ? false : true; W(jXOgs+_
} n~~0iU)
/S4$qr cM
privatestaticboolean hasNextPage(int currentPage, IQn|0$':Z
8MUY
int totalPage){ +um
Ua
return currentPage == totalPage || totalPage == PL+r*M%ll
X|o;*J](
0 ? false : true; :r5DR`Rfm
} K)NB{8 _
B[XVTok
=W+ h.?
} /u
hA\m(
%:61@<
tE&@U$0>o
""AP-7
Q[g>ee
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 S
b0p?
,'=Tf=wq
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 CM$q{;y
sK1YmB :~a
做法如下: oWCy%76@
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 4sU*UePr
j?!BHNs
的信息,和一个结果集List: Kob i!
java代码: I~:v X^%9
w8MQA!=l
-TIrbYS`
/*Created on 2005-6-13*/ hN0Y8Ia/5%
package com.adt.bo; <P)U Ggd
%V40I{1
import java.util.List; g&z)y
Z0o+&3a6
import org.flyware.util.page.Page; -)cau-(X
=m<; Jx5
/**
=+I~K'2
* @author Joa QU`M5{#
*/ ~3]ZN'b\
publicclass Result { 93Z/|7
f?KHp|
private Page page; p]/qf\E
Eqx2.S
private List content; "Jd!TLt\x
P'EPP*)q
/** n^} -k'l
* The default constructor fY)Dx c&ue
*/ #Az#dt]H
public Result(){ Z )Imj&;
super(); |r5e#3w
} ixK&E#
XUI9)Ne
/** $-HP5Kj(k-
* The constructor using fields F0yvV6;
* jO` b&]0
* @param page 0D x,)C
* @param content nC-=CMWWr
*/ i5f8}`w
public Result(Page page, List content){ $P=B66t
^
this.page = page; J%8M+!`F
this.content = content; 4CUoXs'
} 2(SU# /,
<>gX'te
/** TH;kJ{[}
* @return Returns the content. ny(`An
*/ 8$!&D&v
publicList getContent(){ Qqp_(5S|>
return content; 4*j6~
} |@84l
dA)JR"r2
/** o'oA.'ul
* @return Returns the page. (8Q0?SZN
*/ )K=%s%3h<
public Page getPage(){ 3K8#,TK3
return page; 5y
9(<}z
} @W4tnM,#
.G ^-.p
/** #hp7@ Tu
* @param content 'H19@b5rx
* The content to set. K;:_UJ>t
*/ uX.^zg]}%
public void setContent(List content){ e8WuAI86
this.content = content; b"Z$?5
} pKxsK^O5[
IE)$.%q;)
/** aw%iO|M_
* @param page fX
^hO+f
* The page to set. }9Th`
*/ ce3UB~Q
publicvoid setPage(Page page){ kp6{QKDj&
this.page = page; nrhzNW>]
} >)Udb//
} $ \yZ;Z:
wZ(H[be
~pZ<VH;h
<Ny DrO"C3
Io(*_3V)B
2. 编写业务逻辑接口,并实现它(UserManager, 4# L}&
KT4h3D`,
UserManagerImpl) 3jI
rB%
java代码: F@%`(/^TA
P&>!B,f
EbfE/_I
/*Created on 2005-7-15*/ X7bS{GT
package com.adt.service; Daw;6f:
g3Xa b
import net.sf.hibernate.HibernateException; yd}1Mx
|]Eli%mNe
import org.flyware.util.page.Page; <Jf[N=
n@JZ 2K4
import com.adt.bo.Result; '^{:HR#i
+55+%oGl
/** Ah?,9r=U
* @author Joa ^t$xR_
*/ @^2?97i
c
publicinterface UserManager { O x),jc[/
=d*5TyAcu
public Result listUser(Page page)throws t=;P1d?E;
8ofKj:W]
HibernateException; rjo1
N^TE
;BM
} @Y&UP
TwI'}J|w
(
kKQs")
^.pd'
xXRlQ|84
java代码: 2.2G79U,
\C}_l+nY
mm:g9j
/*Created on 2005-7-15*/ ;ztt*py
package com.adt.service.impl; JW}O`H9
+V `*
import java.util.List; l+UUv]:1
T&q0TBT
import net.sf.hibernate.HibernateException; \3WQ<t)W
Wb%t6N?
import org.flyware.util.page.Page; V{{Xz:
import org.flyware.util.page.PageUtil; #]kO/Mr
R_zQiSwG<
import com.adt.bo.Result; h]jy):9L
import com.adt.dao.UserDAO; a;h.I}*]
import com.adt.exception.ObjectNotFoundException; V#,jUH|
import com.adt.service.UserManager; ccY! OSae
:Ldx^UO
/** 0@tN3u?dx
* @author Joa v;o/M6GL5
*/ (3Dz'X
publicclass UserManagerImpl implements UserManager { o()No_.8H
d=DQS>Nz
private UserDAO userDAO; V sQ~Y,7
Fz {T;
/** i}gsxq%
* @param userDAO The userDAO to set. KK';ho,W
*/ O63:t$Yx#
publicvoid setUserDAO(UserDAO userDAO){ I/hq8v~S
this.userDAO = userDAO; !zQbF&>
} ]2
wZ%a:Z4TcM
/* (non-Javadoc) tyU'[LF?
* @see com.adt.service.UserManager#listUser sKwUY{u\M
[:(hqi!
(org.flyware.util.page.Page) T&nIH[}v
*/ ".7\>8A#a
public Result listUser(Page page)throws H(gETRh
^oMdx2Ow#
HibernateException, ObjectNotFoundException { >e^^YR^
int totalRecords = userDAO.getUserCount(); 'w8p[h
(,
if(totalRecords == 0) VC X^D)[-
throw new ObjectNotFoundException 80%L!x|
e X{#FgFc
("userNotExist"); 8'*/|)Hn
page = PageUtil.createPage(page, totalRecords); Q#5~"C
List users = userDAO.getUserByPage(page); ;J,`v5z0:
returnnew Result(page, users); 7V2xg h!W
} ez14f$cJ+
mMw--Gc?
} IAi|4,y_L
/@?lV!QiO
[.'9Sw
J3XrlSc
Tn"^`\m
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 5ENEx
~X<?&;6
询,接下来编写UserDAO的代码: FWW*f
_L
3. UserDAO 和 UserDAOImpl: d]K$0HY
java代码: uH |:gF^
P?hB`5X
+-:o+S`q~
/*Created on 2005-7-15*/ QTospHf`
package com.adt.dao; UuCRQN H
2QgD<
import java.util.List; 9/h[(qvT
8l*h\p:Q
import org.flyware.util.page.Page; FGzn|I
X@ S~D7|ja
import net.sf.hibernate.HibernateException; q.bxnta"
$kBcnk
/** <~zPt&C]V
* @author Joa :n,x?bM
*/ ?|Ey WAL
publicinterface UserDAO extends BaseDAO { UaB2vuL*=
j@R"AP}
publicList getUserByName(String name)throws * .g[vCy
CrB4%W:{
HibernateException; xEg@Y"NQ
NwN3T]W
publicint getUserCount()throws HibernateException;
Dn#^-,H
cAq5vAqmg
publicList getUserByPage(Page page)throws G_`Ae%'h
t=fr`|!
HibernateException; w!jY(WKU
PlR$s
} e5d STc`
{dYz|O<
$;rvKco)%
W[:CCCDL
`<-/e%8
java代码: M<r]a{Yv
Gkm{b[
W~FU!C?]
/*Created on 2005-7-15*/ *|ef #-|D
package com.adt.dao.impl; 1&RB=7.h
Vqr]Ui
import java.util.List; w:ASB>,!
ZgfhNI\
import org.flyware.util.page.Page; B'I_i$g4w
|G/U%?`
import net.sf.hibernate.HibernateException; kqjj&{vPFJ
import net.sf.hibernate.Query; ?)H:.]7-x
Sd/7#
import com.adt.dao.UserDAO; vxS4YR b
V
n+a-v
/** (7ujJ}#,
* @author Joa 2(5/#$t
*/ eo~b]D
public class UserDAOImpl extends BaseDAOHibernateImpl /!%?I#K{Wq
tn;{r
implements UserDAO { /VD[: sU7
UrO&K]Z
/* (non-Javadoc) S`Z[MNY
* @see com.adt.dao.UserDAO#getUserByName NA$%Up
ipE|)Ns
(java.lang.String)
[?bq4u`
*/ U6.hH%\}@
publicList getUserByName(String name)throws v'm-A d+4t
yxi&80$
HibernateException { %, S{9q
String querySentence = "FROM user in class o]WcODJdl
y>cLG5v
com.adt.po.User WHERE user.name=:name"; ]Upr<!
Query query = getSession().createQuery vl~HV8MAv
UW1i%u
k
(querySentence); 51-'*Y
query.setParameter("name", name); }0sLeGJ!
return query.list(); 5"ooam3
} ..5.":
RXw1HRR$V
/* (non-Javadoc) 1bjz :^
* @see com.adt.dao.UserDAO#getUserCount() CF:L#r
*/ S f6%A
publicint getUserCount()throws HibernateException { z<%dWz
int count = 0; "ruYMSpU
String querySentence = "SELECT count(*) FROM -d-xsP}
s
Q.fUpa v
user in class com.adt.po.User"; Q5A,9ovNZ
Query query = getSession().createQuery G'`^U}9V\
"gFw:t"VV
(querySentence); uAs!5h
count = ((Integer)query.iterate().next (b.4&P"0
UCj:]!P
()).intValue(); _GM?`
return count; >
H&v
} P 5.@LN
OO</d:
/* (non-Javadoc) xUNq!({T
* @see com.adt.dao.UserDAO#getUserByPage 5gkQ6&m
/N#=Tol
(org.flyware.util.page.Page) hAt4+O&P
*/ ;GKL[tI"
publicList getUserByPage(Page page)throws oF a,IA
1M b[S{
HibernateException { ObJ-XNcNH
String querySentence = "FROM user in class <oi'yr
?op;#/Q(
com.adt.po.User"; \4>w17qng
Query query = getSession().createQuery eSHsE3}h
{|<yZ,,p
(querySentence); 7rYBFSp
query.setFirstResult(page.getBeginIndex()) =oM#]M'G+(
.setMaxResults(page.getEveryPage()); = l:k($%%
return query.list(); maa$kg8U*!
} KoA +Vv9
7w]3D
} N|%r5%
=k,?+h~
X,Rl&K\b"
#;5Qd'
MPK rr
至此,一个完整的分页程序完成。前台的只需要调用 JH u>\{ 8V
HAo=t
userManager.listUser(page)即可得到一个Page对象和结果集对象 $:# :"
w~:F?
的综合体,而传入的参数page对象则可以由前台传入,如果用 6(x53y__
;Qi!~VsP;
webwork,甚至可以直接在配置文件中指定。 vxug>2
=qbN?a/?2
下面给出一个webwork调用示例: VFMn"bYOB
java代码: 'p78^4'PL
X&h?1lMJ /
PVIZ
Y^64
/*Created on 2005-6-17*/ q[+h ~)
package com.adt.action.user; G
B,O
ti$60Up
import java.util.List; ;nJ2i?"
NpCQ4K
import org.apache.commons.logging.Log; <lNNT6[/r
import org.apache.commons.logging.LogFactory; $|7=$~y
import org.flyware.util.page.Page; X|/RV4x@Cq
Ptcq/f
import com.adt.bo.Result; f mJK+
import com.adt.service.UserService; cr|]\
import com.opensymphony.xwork.Action; CU*TY1%
t)uxW
7
/** kr@!j@j$
* @author Joa 3,`M\#z%K
*/ KhP_U{)D
publicclass ListUser implementsAction{ Zy.A9Bh~
h_\(
$"
privatestaticfinal Log logger = LogFactory.getLog CBNt
_y
mIp> ~
(ListUser.class); Q2)(tB= )
IOF!Ra:w
private UserService userService; A:D9qp
^FQn\,
private Page page; =,C]d~
~kj96w4eAR
privateList users; ?m+];SJk
Ju&FwY+
/* H "5,To
* (non-Javadoc) 'n1$Y%t
* .{ZJywE<
* @see com.opensymphony.xwork.Action#execute() J7C?Z
*/ HG< z,gE
2
publicString execute()throwsException{ -T i<H9OV
Result result = userService.listUser(page); C9!FnvH
page = result.getPage(); I{ki))F
users = result.getContent(); =
Ezg3$%-
return SUCCESS; xK)<763q>
} AAW] Y#UwW
lrwQ
>N
/** ]~VuY:abH
* @return Returns the page. -QR]BD%J*[
*/ AWPgrv/
public Page getPage(){ P;-.\VRu
return page;
2VUN
} r%WHYhD
Qds:*]vGS
/** h-sO7M0E]
* @return Returns the users. !syyOfu`}
*/ fAz4>_4
publicList getUsers(){ NFtA2EMLu[
return users; MK @rx6<9
} jJNl{nyq
3TLym&
/** J]zhwM
* @param page @o*~\E<T
* The page to set. M(:bM1AD`u
*/ 9Iq<*\V 4
publicvoid setPage(Page page){ +'iqGg-
this.page = page; $aB`A$'hK
} oM^vJ3
Q4*{+$A
/** &/2+'wCp5
* @param users "L`BuAB
* The users to set. {O).!
*/ 2L[!~h2
publicvoid setUsers(List users){ 2<h~:
L
this.users = users; ;K|K]c
} f2pA+j5[
^c/3!"wK
/** w|6?A-
* @param userService f*88k='\W
* The userService to set. y29G#Y4J
*/ @8w5Oudvx
publicvoid setUserService(UserService userService){ vJct)i
this.userService = userService; v@ qDR|?^
} 0_-o]BY
} *93=}1gN
^'du@XCf}
2~7*jA+Ab
_Gt;=
i `p1e5$
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, 7lAJ
0
W"pHR sf
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 =sv?))b`
Nu3IYS5&
么只需要: T-GvPl9ZJw
java代码: cTn(Tv9s
VAjl?\}6
qmGHuQVe
<?xml version="1.0"?> AS:k&t
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork f<$*,P
( xzruI5P
1.0//EN" "http://www.opensymphony.com/xwork/xwork- oOLA&N-A~
5D?{dA:Rq
1.0.dtd"> 0bJT0_
X(17ESQ/Y
<xwork> \6.dGKK
|
2<zYY
<package name="user" extends="webwork- WBJn1
#*lDKn[vO
interceptors"> q[W@.[2y)
uHbbPtk
<!-- The default interceptor stack name VPuo!H
p\#;(pf}s
--> 5 8L@:>"
<default-interceptor-ref ]TUoXU2<x
/X0<2&v
name="myDefaultWebStack"/> lx0BKD?n
",[ /pb
<action name="listUser" g`C"t3~%S
=B'Yx
class="com.adt.action.user.ListUser"> i$}G[v<4
<param )+hJi/g
_8-1wx
name="page.everyPage">10</param> Er8F_,M+
<result W!kF(O
NA
._;It198f
name="success">/user/user_list.jsp</result> =w8 0y'
</action> lA4J#
38l:Y"
</package> &z*4Uij
"?<`]WG\
</xwork> Au/'|%2#(
\>EUa}%xn
P, F5Hf
F.(e}EMyNh
qzHsqlof
J8@+)hn
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 `:m=rT_
PR(KDwsT&l
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。 M&",7CPD(1
!Q%r4Nr
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 SX =^C
#Q_<eo%lI*
X MF? y
N!v>2"x8q
]d%Ou]609
我写的一个用于分页的类,用了泛型了,hoho ts@e
,
W$l4@A
java代码: Z$m&F0g
?vF8 y;Jh
(r'NB
package com.intokr.util; )PkGT~3I
&Q\k`0vzVB
import java.util.List; [Q6$$z92Q
7~P!Z=m^^f
/** $gk=~p|
* 用于分页的类<br> 8(A
k
* 可以用于传递查询的结果也可以用于传送查询的参数<br> w)YTHY(k;
* &?y|Pn
* @version 0.01 |\"%Dy[m
* @author cheng i*09m^r
*/ \Km+>G
public class Paginator<E> { 7<2?NLE8*
privateint count = 0; // 总记录数 eCg|@d% D
privateint p = 1; // 页编号 kZ:~m1dd
privateint num = 20; // 每页的记录数 $SniQ
privateList<E> results = null; // 结果 ^Ga_wJP8S
Spo[JQ%6
/** CJ#Yu3}
* 结果总数 #0#6eT{-
*/ la]Zk
publicint getCount(){ G"vEtNoV
return count; \tS|
N40
} NB( GE
'$ G%HUn
publicvoid setCount(int count){ 9N) Ea:N
this.count = count; C8:y+pH_U;
} xFp9H'j{
"68=dC
/** A/j'{X!z
* 本结果所在的页码,从1开始 1ahb:Mjv
* w%6 L"
* @return Returns the pageNo. Fy_~~nI0
*/ ??P3gA
publicint getP(){ [t5D d
return p; L>57eF)7
} g^\>hjNX
2Myz[)<P_
/** >Y:veEa6v6
* if(p<=0) p=1 (1Jc-`
* @XKVdtG
* @param p 3);Wgh6
*/ 8{CBWXo$)
publicvoid setP(int p){ IF?
if(p <= 0) $')Uie<!8
p = 1; q }9n.
this.p = p; 4&`d$K
} {?IUf~<
bGB5]%v,
/** zn\$6'"
* 每页记录数量 ).$kp2IN
*/ 2QIo|$
publicint getNum(){ VZA>ErB
return num; FvBnmYnW
} %-NG eN8
s!
sG)AR.J
/** L7.LFWq$S
* if(num<1) num=1 mi sPJO&QD
*/ DJR r
publicvoid setNum(int num){ )VxC v
if(num < 1) 6wyhL-{:
num = 1; 93Qx+oK]
this.num = num; xn7bb[g;
} U }}E
E~W
NX<Q}3cC
/** #~qY%X
* 获得总页数 9z?B@;lMc
*/ FzFP 0
publicint getPageNum(){ FOX0
return(count - 1) / num + 1; gAy"W$F
} DEKO]i
88atj+N]
/** ,aSK L1
* 获得本页的开始编号,为 (p-1)*num+1 )7N$lY<
*/ V"sm+0J
publicint getStart(){ 5U JMiwP{
return(p - 1) * num + 1; <d3N2
} (_~Dyvo
"eKM<S
/** BH?fFe&J:`
* @return Returns the results. K%>3ev=y.s
*/ p{rzP,Pb&
publicList<E> getResults(){ *3!ixDX[r
return results; 4=hz4(5a
} YR68'Sft[
xgB-m[Xi
public void setResults(List<E> results){ 'C1yqkIa`
this.results = results; xO'xZ%cUI
} A)o%\j
f<2<8xS
public String toString(){ G%fNGQwT
StringBuilder buff = new StringBuilder Kdb:Q0B
^g N?Io
(); _~E_#cNn
buff.append("{"); 0Y ld!L
buff.append("count:").append(count); (k5d.E]CK
buff.append(",p:").append(p); 3VmF1w
2
buff.append(",nump:").append(num); 1?ST*b
buff.append(",results:").append SV_b(wP9
)'t&LWS~
(results); NiH.Pv)Oa'
buff.append("}"); ~C ;gEE-
return buff.toString(); Vb8{OD3PK
} Ezw<
AU
H_~SY
} *Y9' tHI
^o6&|q
WzO[-csy