Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 EX"yxZ~
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 :'ptuY
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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 p4QU9DF
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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 =MWHJ'3-/
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。 iRBfx
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分页支持类: 'fW-Y!k%
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java代码: Bp{Ri_&A
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package com.javaeye.common.util; 1Ws9WU
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import java.util.List; T>>c2$ x
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publicclass PaginationSupport { Xc.`-J~Il
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publicfinalstaticint PAGESIZE = 30; cb bFw
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privateint pageSize = PAGESIZE; zeRyL3fnmb
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privateList items; ;a3}~s
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privateint totalCount; hGrdtsH?
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privateint[] indexes = newint[0]; ('~LMu_
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privateint startIndex = 0; V6Dbd"
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public PaginationSupport(List items, int $Q0n
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totalCount){ fy$1YI>!Q
setPageSize(PAGESIZE); 6B-16
setTotalCount(totalCount); t,'<gI
setItems(items); h];I{crh
setStartIndex(0); =M-p/uB]
} wY}@'pzX
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public PaginationSupport(List items, int ]^]wP]R_
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totalCount, int startIndex){ P;*(hY5&
setPageSize(PAGESIZE); }7X%'Bg=M
setTotalCount(totalCount);
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setItems(items); p[cX O=
setStartIndex(startIndex); adw2x pj
} .(vwIb8\_
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public PaginationSupport(List items, int EK'!}OGCG
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totalCount, int pageSize, int startIndex){ iQ{VY
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setPageSize(pageSize); n`KY9[0U=
setTotalCount(totalCount); F[0]/
setItems(items); W9)&!&<o
setStartIndex(startIndex); F!do~Z
} ,0k;!YK
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publicList getItems(){ &wX]_:?
return items; Ep}s}Stlr}
} ElXFeJ%[G
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publicvoid setItems(List items){ [
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this.items = items; `x|?&Ytmf9
} Mfs?x
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publicint getPageSize(){ K%d&EYoW]
return pageSize; Je{ykL?N
} BuwY3F\-O
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publicvoid setPageSize(int pageSize){ [!z,lY>
this.pageSize = pageSize; 8-i#8'/x
} he4(hX^
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publicint getTotalCount(){ % `3jL7|
return totalCount; :-'qC8C
} 36NpfTW
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publicvoid setTotalCount(int totalCount){ l,8##7
if(totalCount > 0){ MPV5P^@X
this.totalCount = totalCount; nR~(0G,H
int count = totalCount / PM+[,H
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pageSize; 3 Y &d=
if(totalCount % pageSize > 0) &vJH$R
count++; 68
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indexes = newint[count]; 9my^Y9B
for(int i = 0; i < count; i++){ ! z**y}<T
indexes = pageSize * q@qsp&0/
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} <!+Az,-
}else{ YN,A)w:]
this.totalCount = 0; N$DkX)Z
} ^_6|X]tz1T
} g*Phv|kI
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publicint[] getIndexes(){ +:f"Y0
return indexes; hc1N~$3!G
} `gJ(0#ac
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publicvoid setIndexes(int[] indexes){ ?`#Khff?
this.indexes = indexes; y*? Jui Q
} nEfK53i_
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publicint getStartIndex(){ q<J~ ~'
return startIndex; Nl/dX-I
} ]yu:i-SfP
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publicvoid setStartIndex(int startIndex){ XkqCZHYkS
if(totalCount <= 0) GeqPRah
this.startIndex = 0; O8o3O
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elseif(startIndex >= totalCount) u y+pP!<
this.startIndex = indexes ~dSr5LUD
: +u]S2u{
[indexes.length - 1]; z{6Z
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elseif(startIndex < 0) G)YcJv7
this.startIndex = 0; H.;Q+A,8^
else{ q| 7(
this.startIndex = indexes >sF)BoLc
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[startIndex / pageSize]; @d_M@\r=j
} Lr+$_ t}r
} )_:NLo:
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publicint getNextIndex(){ [K Qi.u
int nextIndex = getStartIndex() + 8(De^H lO
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pageSize; {I((p_
if(nextIndex >= totalCount) %xW"!WbJ|
return getStartIndex(); 7^285)UQA
else vI?, 47Hj+
return nextIndex; 0_/[k*Re
} >!JS:5|
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publicint getPreviousIndex(){ _g8yDfcLG
int previousIndex = getStartIndex() - +t.b` U`-
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pageSize; [UR-I0 s!/
if(previousIndex < 0) 6Zo}(^Ovz
return0; hoP]9&<T
else ~Ei<Z`3}7"
return previousIndex; 5G#n"}T
} RCrCs
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} #4:?gfIj
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抽象业务类 =I<R! ZSN
java代码: &m3lXl
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/** GyIV
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* Created on 2005-7-12 x2EUr,7
*/ _!6jR5&r,
package com.javaeye.common.business; H}!r|nG
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import java.io.Serializable; ?[AD=rUC
import java.util.List; /z!%d%"
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import org.hibernate.Criteria; w
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import org.hibernate.HibernateException; 7_L;E~\
import org.hibernate.Session; XSDpRo
import org.hibernate.criterion.DetachedCriteria; g-A-kqo9
import org.hibernate.criterion.Projections; a[C@
import ok[i<zl;'
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org.springframework.orm.hibernate3.HibernateCallback; m*pJBZxd
import ]lbuy7xj63
. vV|hSc
org.springframework.orm.hibernate3.support.HibernateDaoS \G[$:nS
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upport; 2HdC |$_+
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import com.javaeye.common.util.PaginationSupport;
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public abstract class AbstractManager extends >j/w@Fj
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HibernateDaoSupport { +2{Lh7Ks
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privateboolean cacheQueries = false; l-Z4Mq6*L
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privateString queryCacheRegion; WE?5ehEme
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publicvoid setCacheQueries(boolean 3n _htgcv
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cacheQueries){ u_enqC3
this.cacheQueries = cacheQueries; !zo{tI19
} v+XJ*N[W
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publicvoid setQueryCacheRegion(String .]^?<bG
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queryCacheRegion){ G[=c
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this.queryCacheRegion = $i&zex{\
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queryCacheRegion; _XBd3JN@
} C]6O!Pb0
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publicvoid save(finalObject entity){ d6O[ @CyP
getHibernateTemplate().save(entity); 5O%{{J
} (>Em^(&
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publicvoid persist(finalObject entity){ {FkF
getHibernateTemplate().save(entity); &Jj<h: *
} kmW4:EA%
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publicvoid update(finalObject entity){ J5qZFD
getHibernateTemplate().update(entity); -f .,tM=
} c)J%`i$
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publicvoid delete(finalObject entity){ 7! Nsm
getHibernateTemplate().delete(entity); It(_v
} #"!<W0
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publicObject load(finalClass entity, TOt dUO
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finalSerializable id){ ZVBXx\{s
return getHibernateTemplate().load L0,'mS
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(entity, id); COlqcq'qAu
} >Tgv11[
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publicObject get(finalClass entity, <I?Zk80
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finalSerializable id){ sRs>"zAg
return getHibernateTemplate().get dV_G1'
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(entity, id); **%37
} lxx2H1([
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publicList findAll(finalClass entity){ .#gzP2 [q
return getHibernateTemplate().find("from MtdG>TzUn
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" + entity.getName()); XS#Qu=,-
} Hl"N}
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publicList findByNamedQuery(finalString u9e@a9c
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namedQuery){ [n@]
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return getHibernateTemplate u`W2+S
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().findByNamedQuery(namedQuery); >:-$+I
} (`^1Y3&2
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publicList findByNamedQuery(finalString query, X?O[r3<
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finalObject parameter){ V[LglPt
return getHibernateTemplate VA%J\T|G2\
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().findByNamedQuery(query, parameter); ="+#W6bZT
} z/-=%g >HA
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publicList findByNamedQuery(finalString query, $Sq:q0
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finalObject[] parameters){ Q &8-\
return getHibernateTemplate Oketwa
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().findByNamedQuery(query, parameters); x2xRBkRg=
} 6nn*]|7
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publicList find(finalString query){ MgZ/(X E
return getHibernateTemplate().find %9"H
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(query); _a, s
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} ,1`z"7\W
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publicList find(finalString query, finalObject pa+hL,w{6
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parameter){ VbYdZCC
return getHibernateTemplate().find _ q"Gix
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(query, parameter); 6tZI["\
} zLQx%Yg!
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public PaginationSupport findPageByCriteria _`X:jj>
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(final DetachedCriteria detachedCriteria){ P \I|,
return findPageByCriteria Pz7XAcPQ(
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); HS$r8`S?)
} 3]hWfj1m2
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public PaginationSupport findPageByCriteria 4euO1=
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(final DetachedCriteria detachedCriteria, finalint vN $s|R'@
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startIndex){ (Ld i|jL
return findPageByCriteria BT$_@%ea&
)J |6 -C
(detachedCriteria, PaginationSupport.PAGESIZE, TeQV?ZQ#}
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startIndex); DU^loB+
} P?<y%c<
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public PaginationSupport findPageByCriteria _1^'(5f$
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(final DetachedCriteria detachedCriteria, finalint c-w)|-ac.
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pageSize, )7@0[>
finalint startIndex){ )oZ dj`
return(PaginationSupport) DG/Pb)%Y
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getHibernateTemplate().execute(new HibernateCallback(){ 9WHddDA
publicObject doInHibernate HW|IILFB
[
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(Session session)throws HibernateException {
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Criteria criteria = \e_O4
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detachedCriteria.getExecutableCriteria(session); N`i/mP
int totalCount = fA-7VdR`R
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((Integer) criteria.setProjection(Projections.rowCount pAEx#ck
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()).uniqueResult()).intValue(); t^HRgY'NjM
criteria.setProjection s2?&!
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(null); Ac6=(B
List items = %y@AA>x!
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criteria.setFirstResult(startIndex).setMaxResults y(Td/rY.
9uY'E'm*
(pageSize).list(); <3iMRe
PaginationSupport ps = 0(Ij%Wi,
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new PaginationSupport(items, totalCount, pageSize, a.'*G6~Qgw
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startIndex); b6[j%(
return ps; qR.Q,(b|
} N!3 2 wJ
}, true); ^8tEach
} C~[,z.FvO
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public List findAllByCriteria(final wr4:Go`
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DetachedCriteria detachedCriteria){ fM}#ON>Z
return(List) getHibernateTemplate E]6
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().execute(new HibernateCallback(){ _@g;8CA
publicObject doInHibernate tkhCw/
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(Session session)throws HibernateException { ]4{H+rw
Criteria criteria = -M2yw
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detachedCriteria.getExecutableCriteria(session); iE{&*.q_}>
return criteria.list(); _ |p8M!
} j|n R"!
}, true); H]!"Zq k
} 598i^z{~0%
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public int getCountByCriteria(final zX~MC?,W1
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DetachedCriteria detachedCriteria){ t5zKW _J7
Integer count = (Integer) %SI'BJ
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getHibernateTemplate().execute(new HibernateCallback(){ f)!Z~t &
publicObject doInHibernate Fi1@MG5$2
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(Session session)throws HibernateException { P4?glh q#
Criteria criteria = ddo#P%sH'
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detachedCriteria.getExecutableCriteria(session); 8Y3I0S
return y]imZ4{/
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criteria.setProjection(Projections.rowCount Wm|lSisY
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()).uniqueResult(); "j-CZ\]U|
} r/sNrB1U"y
}, true); U&xUfBDt
return count.intValue(); H-%v3d>3
} q=G+Tocv
} G`zm@QL
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用户在web层构造查询条件detachedCriteria,和可选的 P$sxr
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 )i<j XZ:O
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PaginationSupport的实例ps。 Ug`djIL
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ps.getItems()得到已分页好的结果集 b2]Kx&!
ps.getIndexes()得到分页索引的数组 jIF
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ps.getTotalCount()得到总结果数 Bf:Q2slqI
ps.getStartIndex()当前分页索引 B:QHwzd
ps.getNextIndex()下一页索引 i&k7-<
ps.getPreviousIndex()上一页索引 W l16`9
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 rH>)oThA#
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 PzGWff!*n
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一下代码重构了。 %bfZn9_m
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我把原本我的做法也提供出来供大家讨论吧: X?$_Sd"G+5
Sc
首先,为了实现分页查询,我封装了一个Page类: 4 OX^(
java代码: "]iB6
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/*Created on 2005-4-14*/ go"Hf_
package org.flyware.util.page; O~QB!<Q+
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/** Z8oK2Dw
* @author Joa !a<ng&H^U
* 4&f3%eTi
*/ D0q":WvE
publicclass Page { T^v}mWCZ
>*n0n!vF
/** imply if the page has previous page */ 1QJL .
privateboolean hasPrePage; BUR*n;V`
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/** imply if the page has next page */ _[y/Y\{I
privateboolean hasNextPage; '7@R7w!E4H
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/** the number of every page */ )Wox Mmz
privateint everyPage; 9E tz[`|
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/** the total page number */ W];dD$Oqg
privateint totalPage; N36_C;K-z
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/** the number of current page */ 3&/Ixm:
privateint currentPage; z~Q>V]a>;
; Hd7*`$
/** the begin index of the records by the current f`/x"@~H5
+@:x!q|^
query */ h=%_Ao<x
privateint beginIndex; \j)E5b+
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/** The default constructor */ i@BtM9:
public Page(){ z"4~P3>{g
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} sse.*75U
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/** construct the page by everyPage M|[o aanY'
* @param everyPage t. '!`5G
* */ ))i }7chc
public Page(int everyPage){ G/mXq-
this.everyPage = everyPage; `V3Fx{
} 4NIRmDEd
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/** The whole constructor */ {vO9ptR;
public Page(boolean hasPrePage, boolean hasNextPage, RAK-UN
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int everyPage, int totalPage, }-3mPy(*%
int currentPage, int beginIndex){ Uv~QUL3>
this.hasPrePage = hasPrePage; T"}vAG( .O
this.hasNextPage = hasNextPage; LYg-
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this.everyPage = everyPage; :U(A;U1,
this.totalPage = totalPage; a -moI+y
this.currentPage = currentPage; /[>sf[X\I9
this.beginIndex = beginIndex; SC])?h-Fw
} UEVG0qF
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/** ^w06<m
* @return u=_mvN
* Returns the beginIndex. bD8Gwi=iiu
*/ ,<p}o\6
publicint getBeginIndex(){ CC^'@~)?
return beginIndex; ^Js9 s8?$
} [R7Y}k:9U
)D82N`c2\i
/** *C=>X193U
* @param beginIndex \K<QmK
* The beginIndex to set. w(TJ*::T
*/ D+7Rz_=
publicvoid setBeginIndex(int beginIndex){ AlW66YAuQ
this.beginIndex = beginIndex; Clb@$,
} }k
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/** R#8L\1l
* @return ?_"ik[w}
* Returns the currentPage. (41|'eB\\
*/ Yr=Y@~ XL
publicint getCurrentPage(){ hzbw>g+
return currentPage; y[_Q-
}
{ Z5nGG
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/** ;x1PS
* @param currentPage ; XN{x
* The currentPage to set. :7?FF'u
*/ qXtC^n@x
publicvoid setCurrentPage(int currentPage){ ;K&o-y
this.currentPage = currentPage; v(D;PS3r
7
} f\>M'{cV
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/** n%s]30Xs
* @return \1 &,|\E#
* Returns the everyPage. x&T [*i
*/ ^vO+(p
publicint getEveryPage(){ Yv!a88+A8M
return everyPage; TNh1hhJ$b
} aC.~&MxFC
B[-v[K2
/** |:<f-j7t~
* @param everyPage zY!j:FT1HY
* The everyPage to set. I\JGs@I
*/ '>ssqBnI
publicvoid setEveryPage(int everyPage){ Z//+Gw<'
this.everyPage = everyPage; rOOT8nkR#
} ><$d$(
!XCm>]R
/** "z=SO1
* @return 2M'[,Xe
* Returns the hasNextPage. :GP]P^M;G@
*/ R1GEh&U{
publicboolean getHasNextPage(){ :Ab%g-
return hasNextPage; lun\`f 5Q
} 9!}8UALD
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/** Rt!FPoN,y
* @param hasNextPage $$5aUI:$~$
* The hasNextPage to set. c>Xs&_
*/ QY?~ZwYB
publicvoid setHasNextPage(boolean hasNextPage){ j; y#[|
this.hasNextPage = hasNextPage; !F1N~6f
} (HE9V]
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/** 5}]"OXQ
* @return v,{yU\)
* Returns the hasPrePage. Ww%=1M]e-
*/ nV:LqF=
publicboolean getHasPrePage(){ 4$S;(
return hasPrePage; /%TI??PGu
} 'JfdV%M
lP@Ki5
/** pd;br8yE$@
* @param hasPrePage (ECnMti+
* The hasPrePage to set. ^xh ;
*/ LNpup`>`
publicvoid setHasPrePage(boolean hasPrePage){ #32"=MfQn
this.hasPrePage = hasPrePage; -pGE]nwDL
} `_RTw5{
\$e)*9)
/** *b/`Ya4
* @return Returns the totalPage. E5xzy/ZQ
* 1Z~)RJ<D
*/ ~r`9+b[9{
publicint getTotalPage(){ TQ*1L:X7M&
return totalPage; <_tT<5'[$u
} 2Mmz %S'd
bc)~k:
/** S` ;?z
* @param totalPage _Khc3Jo
* The totalPage to set. ()+<)hg}2
*/ X+S9{X#Cm
publicvoid setTotalPage(int totalPage){ EzV96+
this.totalPage = totalPage; v` 7RCg`
} fb8g7H|
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} af+IP_6
.
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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 $!(pF
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个PageUtil,负责对Page对象进行构造: M|qteo
java代码: H{k^S\K
*
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/*Created on 2005-4-14*/ Q[I=T&
package org.flyware.util.page; j|%HIF25
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import org.apache.commons.logging.Log; 7C ,UDp|
import org.apache.commons.logging.LogFactory; .wu
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/** ?zVL;gVWA
* @author Joa f[~L?B;_L
* M8Z2Pg\0
*/ "WK{ >T
publicclass PageUtil { o=?C&f{
5HO9+i
privatestaticfinal Log logger = LogFactory.getLog h!ZV8yMc
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(PageUtil.class); oifv+oY
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/** 7`8Ik`lY
* Use the origin page to create a new page BT"42#7_
* @param page xs:n\N
* @param totalRecords <**y !2
* @return ~UjGSO)z}
*/ ``e$AS
publicstatic Page createPage(Page page, int *nsAgGKKM^
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totalRecords){ BWuqo
return createPage(page.getEveryPage(), OYmR<x5y/
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page.getCurrentPage(), totalRecords); WRDjh7~Efn
} .Pw\~X3!
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/** 3*)ig@e6
* the basic page utils not including exception
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yH*6@P4:0=
handler Zrr5csE
* @param everyPage !M]\I &
* @param currentPage sZm$|T0
* @param totalRecords i21Gw41p:
* @return page i?e`:}T
*/ $Gv9m
publicstatic Page createPage(int everyPage, int /BV03B
x61 U[/r
currentPage, int totalRecords){ H;fxxu`cS
everyPage = getEveryPage(everyPage); z0*_^MH
currentPage = getCurrentPage(currentPage); }HYjA4o\A
int beginIndex = getBeginIndex(everyPage, jR#~I@q^
_({A\}Q|
currentPage); mJ`A_0
int totalPage = getTotalPage(everyPage, {aJJ`t
_}VloiY
totalRecords); )V:]g\t
boolean hasNextPage = hasNextPage(currentPage,
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totalPage); YH_7=0EJ
boolean hasPrePage = hasPrePage(currentPage); -!L"')
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returnnew Page(hasPrePage, hasNextPage, QZhjb
everyPage, totalPage, g
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currentPage, 6]pX>Xho
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beginIndex); T%n2$
} {Gw.l."
@%lBrM
privatestaticint getEveryPage(int everyPage){ zyg
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return everyPage == 0 ? 10 : everyPage; e^Ky<*Y
} z)=+ F]
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privatestaticint getCurrentPage(int currentPage){ 9Xo[(h)5d
return currentPage == 0 ? 1 : currentPage; 0Ir<y
} Gkxj?)`
;6{@^
privatestaticint getBeginIndex(int everyPage, int N**g]T
0`
ee#):
-p
currentPage){ fb:j%1WF
return(currentPage - 1) * everyPage; /q$,'^.A
} (?! ,p^
"a/ Q%.P
privatestaticint getTotalPage(int everyPage, int u@%r
BEgV^\u
totalRecords){ :C8$Xi_i}
int totalPage = 0; "y<?Q}1
$Qy7G{XJ[^
if(totalRecords % everyPage == 0) d@G}~&.|
totalPage = totalRecords / everyPage; rf%7b8[v
else -}6xoF?
totalPage = totalRecords / everyPage + 1 ; OOz[-j>'Y+
W$Yc'E
;
return totalPage; Pv+5K*"7Cg
} V@QK
TSsKfexQ
privatestaticboolean hasPrePage(int currentPage){ mTEx,
return currentPage == 1 ? false : true; .pvV1JA'
} RTu4@7XP
wgRsZ
privatestaticboolean hasNextPage(int currentPage, T}=>C+3r
awUx=%ERtA
int totalPage){ 4~OQhiJ
return currentPage == totalPage || totalPage == R?EASc!b
}AvcoD/b
0 ? false : true; N9<Ujom
} h}Wdh1.M3
1uk0d`JL
3o|I[!2.
} ,mL
!(US
k%op>
&
<JwX_\?ln
!;!~n`
b2b75}_A
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。 +EM_TTf4
&h,5:u
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 ,*@AX>
NCf"tK'5n
做法如下: ,xT?mt}P
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 e%>b+Sv
hwDbs[:
的信息,和一个结果集List: X5*C+ I=2
java代码: ow' lRHZ
ez9k4IO
rqlc2m,<-p
/*Created on 2005-6-13*/ ^U8r0]9
package com.adt.bo; ^:jN3@Q%
yRYWch
import java.util.List; s$*'^:
x)_@9ldYv
import org.flyware.util.page.Page; m%8qZzqk
DBs*Fx[
/** 1]T`n /d V
* @author Joa 2qO3XI
*/ {3Vk p5%l
publicclass Result { Jj^GWZRu
w_iam qe,
private Page page; CC3v%^81l^
l#wdpD a{
private List content; h
!(>7/Gi
zK+52jhi
/** OW(&s,|6x
* The default constructor <[/%{sUNC
*/ ozr9>b>M
public Result(){ 2`=6 %s
super(); :;!\vfZbU
} 'iLH `WE
{hO`6mr&t
/** t=#Pya
* The constructor using fields \ U-vI:J_
* il:nXpM!
* @param page @oG)LT
* @param content ~H}en6Rc
*/ qUF1XJZ}z
public Result(Page page, List content){ 0X(]7b&~R
this.page = page; J:F^
#gW
this.content = content; BXUF^Hj%
} mEuHl>
s2v(=
/** yO>V/5`
* @return Returns the content. WnAd5#G
*/ ; W7Y2Md
publicList getContent(){ *xM/;)
return content; [&P`ak
} Ld|V^9h1;
~L+]n0*
/** ^Dx#7bsDZR
* @return Returns the page. ]wuy_+$
*/ G7* h{nE
public Page getPage(){ cUDg M
return page; !@
YXZ
} W%!@QY;E(
y02u?wJ
/** XvSIWs
* @param content }+Vv0jX|V
* The content to set. IdM*5Y>f
*/ YJ2ro-X
public void setContent(List content){ []&(D_e"
this.content = content; 9F+ P@Kp
} aN^IP
hGP1(pH.
/** Vul+]h[!h
* @param page q3'o|pp
* The page to set. 0d\~"4 R
*/ f3
]
publicvoid setPage(Page page){ =`I?mn&
this.page = page; 3,.%
s
} -0,4egj3
} +EAS Aq
8kW /DcLE
%TK&)Q% h5
4^!4eyQ^
w&lZ42(mF
2. 编写业务逻辑接口,并实现它(UserManager, 5su.+4z\
f(u&XuZ
UserManagerImpl) ]RFdLV?
java代码: BEw{X|7
5 z]\$=TE
$ehg@WK}.
/*Created on 2005-7-15*/ v29G:YQe
package com.adt.service; "~p+0Xws9
N5q725zJ
import net.sf.hibernate.HibernateException; ZcZ;$*
j.QHkI1.
import org.flyware.util.page.Page; z*.v_Mx
?B4#f!X
import com.adt.bo.Result; C;sgK
vg5NY =O
/** B2hfD-h,>
* @author Joa P&t;WPZ
*/ DcFCKji
publicinterface UserManager { R^Bk]
} 21j
public Result listUser(Page page)throws .u< U:*
LC'2q*:'
HibernateException; ( D}"&2
|@`"F5@,
} *:arva5
Sa}D.SBg
w4:<fnOM
\X@IkL$r
56s*A*z$
;
java代码: -fux2?8M
dokuyiN\
Jqg3.2q
/*Created on 2005-7-15*/ #O</\|aH)i
package com.adt.service.impl; aii'}c
BQ#jwu0e
import java.util.List; <"I?jgo
piu0^vEEH
import net.sf.hibernate.HibernateException; 8!j=vCv
uJPH~mdW
import org.flyware.util.page.Page; b|E/LKa
import org.flyware.util.page.PageUtil; &"j@79Ym1~
!P" ?
import com.adt.bo.Result; {aJz. `u\
import com.adt.dao.UserDAO; l @A"U)A(
import com.adt.exception.ObjectNotFoundException; /;+,mp4
import com.adt.service.UserManager; sfC@*Y2XT
MhH);fn
/** &HxT41pku
* @author Joa y#r\b6
*/ {Tx 3$eU
publicclass UserManagerImpl implements UserManager { /'Bdq?!B&
;qT5faKB3J
private UserDAO userDAO; U$$3'n
<`mOU}0)
/** 8OBF^r44R
* @param userDAO The userDAO to set. 4JK@<GBK6
*/ r!M#7FDs(
publicvoid setUserDAO(UserDAO userDAO){ ;8EjjF [>
this.userDAO = userDAO; y7;
5xF?q
} \I
xzdFF#
J/gQQ.s
/* (non-Javadoc) | /#'S&!U
* @see com.adt.service.UserManager#listUser 2HVCXegq
j@V$Mbv
(org.flyware.util.page.Page) \#_@qHAG
*/ Hc
/wta
public Result listUser(Page page)throws ;.r2$/E
}1\?()rB
HibernateException, ObjectNotFoundException { 7CYH'DL
int totalRecords = userDAO.getUserCount(); RhyegD
if(totalRecords == 0) sx90lsu
throw new ObjectNotFoundException |Rk37P{
4Qhx[Hv>(
("userNotExist"); aZC*7AK
page = PageUtil.createPage(page, totalRecords); _3zU,qm+
List users = userDAO.getUserByPage(page); *<CxFy;|
returnnew Result(page, users); Obg@YIwn
} %g5jY%dg.r
Z
c<]^QR
} :3 PG f
9OhR41B
,FS?"Ni
w=gQ3j#s
YN`UTi\s
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Q{`@
G"'
Xv]*;Bq:SK
询,接下来编写UserDAO的代码: i~ROQMN1
3. UserDAO 和 UserDAOImpl: qY# m*R
java代码: \4C)~T:*
Fv;u1Atiw
]P
JH'=
/*Created on 2005-7-15*/ NywB3
package com.adt.dao; Age-AJ
`2sdZ/fO
import java.util.List; ?#U0eb5u
M'b:B*>6
import org.flyware.util.page.Page; yi&?d&rK
.!!79 6hS
import net.sf.hibernate.HibernateException; =tLU]
IBzHR[#,^
/** il=?o f\,i
* @author Joa pFS
F[9?e>
*/ d|R
HG
publicinterface UserDAO extends BaseDAO { 4b]IazL)
osI- o~#>
publicList getUserByName(String name)throws <r@bNx@T
$Gr4sh!cE
HibernateException; gt#MeU
d5N)^\z
publicint getUserCount()throws HibernateException; ;&/sj-xJ2
[))gn
publicList getUserByPage(Page page)throws aS3P(s L
>9<_s
^_
HibernateException; 6R0D3kW
}3bQ>whF
} 3AX?B~s
B'NS&7+].
IJ+O),'
Rv0-vH.n
Q1]V|S;)X
java代码: Rs`Vr_?Hk
7)g;Wd+H
wn&[1gBxM
/*Created on 2005-7-15*/ l!xgtP K
package com.adt.dao.impl; cYBrRTrI#
ddGkk@CA
import java.util.List; 1uKD&k%q
clij|?O
import org.flyware.util.page.Page; [N'r3
=M Q2sb
import net.sf.hibernate.HibernateException; _Y}^%eFw
import net.sf.hibernate.Query; 7{?lEQ&UE
][s*~VK;
import com.adt.dao.UserDAO; #g5't4zqx
\JF57t}Zk
/** bcGn8
* @author Joa iPRJA{$b_
*/ 4nX'a*'D~}
public class UserDAOImpl extends BaseDAOHibernateImpl Udb0&Y1^
<v1_F;{n
implements UserDAO { M%nZu{
=|DkD-
O
/* (non-Javadoc) $D0)j(v
* @see com.adt.dao.UserDAO#getUserByName {EiG23!qV
6|>"0[4S
(java.lang.String) )o}=z\M-bN
*/ 7z0;FW3>9
publicList getUserByName(String name)throws S1 R #]
?w|\7T.?
HibernateException { x<)!$cg
String querySentence = "FROM user in class ?CL z@u~
_&8KB1~
com.adt.po.User WHERE user.name=:name"; )^QG-IM
Query query = getSession().createQuery F~11 _
TLR Lng
(querySentence); {d{WMq$
query.setParameter("name", name); $)WH^Ir~
return query.list(); r&LCoe'\{i
} P^o"PKA
d-_93
/* (non-Javadoc) 8k*k
* @see com.adt.dao.UserDAO#getUserCount() wE.@0
*/ Cys/1DkE
publicint getUserCount()throws HibernateException { =#PudF.\
int count = 0; +eH=;8
String querySentence = "SELECT count(*) FROM )Uoe~\
's%ct}y\J
user in class com.adt.po.User"; C$EFh4
Query query = getSession().createQuery j+ T\c2d
ek_i{'hFd
(querySentence); hPX2 Bp
count = ((Integer)query.iterate().next s^x ,S
LqH?3):
()).intValue(); Lu u-c<*M
return count; r>D[5B
} 2{Lc^6i(t
:EmMia-)J
/* (non-Javadoc) 9Y*Vz QE
* @see com.adt.dao.UserDAO#getUserByPage yO69p
FCw
VVF0y
(org.flyware.util.page.Page) +k"8e?/e.
*/ ;L/T}!Dx
publicList getUserByPage(Page page)throws @a{v>)
6CzvRvA*P
HibernateException { c~u
F
String querySentence = "FROM user in class #)c;i<Q3S
:X'U`jE
com.adt.po.User"; OW5|oG
Query query = getSession().createQuery > & lg
'3kL=(
(querySentence); PT5ni6
query.setFirstResult(page.getBeginIndex()) ?}>B4Z)
.setMaxResults(page.getEveryPage()); 2%, ' }Bus
return query.list(); 1=cfk#
} ,t,65@3+b
[!|d[
} c^/?VmCQ}
QRc=-Wu_(
lKD<
AhFI, x
N4JL.(m){I
至此,一个完整的分页程序完成。前台的只需要调用 Xf/<.5A
7|?@\ZE
userManager.listUser(page)即可得到一个Page对象和结果集对象 [,V92-s;N
6P[O8
的综合体,而传入的参数page对象则可以由前台传入,如果用 /[|md0,
'm.XmVZL%
webwork,甚至可以直接在配置文件中指定。 t7`Pw33#kY
a!]QD`
下面给出一个webwork调用示例: '/)_{Ly
java代码: T<~[vjA
iZqFVr&JF
o+WrIAR
/*Created on 2005-6-17*/ .A f)y_
package com.adt.action.user; YSUH*i/%
XzwQ,+IAr
import java.util.List; Zvw3C%In
9MlfZsby
import org.apache.commons.logging.Log; }qX&*DU_@
import org.apache.commons.logging.LogFactory; 74N\G1
import org.flyware.util.page.Page; Bwvc@(3v
[Z&s0f1Qb
import com.adt.bo.Result; | gxB;
GG
import com.adt.service.UserService; kj"_Y"q=
import com.opensymphony.xwork.Action; WX$^[^=HC
rMFf8D(Y
/** (N>ew)Ke
* @author Joa CX2q7azG
*/ :JG}%
publicclass ListUser implementsAction{ *j; r|P;g
YuW\GSV00
privatestaticfinal Log logger = LogFactory.getLog ])";Z
YQd&rkr
(ListUser.class); bI0+J)
~Am
%%$
private UserService userService; 17i@GnbNb
.j@n6RyN
private Page page; "f$A0RL
OnPLz"-
privateList users; ue2nfp
u,k8i:JY
/* ju6_L<
* (non-Javadoc) m9i%U
* -m-WUox4"
* @see com.opensymphony.xwork.Action#execute() t|XC4:/>T
*/ by3kfY]4s
publicString execute()throwsException{ x \{jWR%
Result result = userService.listUser(page); PH=8'GN
page = result.getPage(); F4l6PGxF&\
users = result.getContent(); QU;C*}0Zl
return SUCCESS; K&oO+ G^f
} K%@SS8!oy
T1TZ+\
/** .-*nD8b
* @return Returns the page. ^]K)V
*/ zL{@LHP
public Page getPage(){ g5'bUYsa
return page; yc}t(*A5
} AR2+W^aM3
cLF>Jvs*J
/** QVhBHAw
* @return Returns the users. vDb}CQ\
*/ pAL-Pl9z
publicList getUsers(){ `-\JjMSQ1
return users; u _^=]K;
} bhT]zsBK
2UJ0%k
/** : \`MrI^
* @param page =l_"M
* The page to set. Q)dns)_x
*/ 'hWRwP|
publicvoid setPage(Page page){ D1/$pA+B
this.page = page; =jHy6)6w
} NP/2gjp
Z@umbyM
/** gQGiph |
* @param users eT?LMBn\
* The users to set. +t6m>IBu
*/ t,YAk
?}
publicvoid setUsers(List users){ hY'%SV
p
this.users = users; ;sJ2K"c
} #bH[UId[
a}{! %5
/** GDntGTE~sk
* @param userService Fje%hcV
* The userService to set. P;[mw(
*/ 4h(Hy&1C
publicvoid setUserService(UserService userService){ hQeZI+
this.userService = userService; ?uv%E*TU
} 2F]MzeW
} s os&
34+}u,=
zW.sXV,
9|DC<Zn&B#
;c}];ZU3G
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, +r"$?bw'
,iy
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 k$/].P*!
dy'?@Lj;
么只需要: B&D
z(Bs
java代码: jz0\F,s
&Gl&m@-j
&*SnDuc
<?xml version="1.0"?> !ZdUW]
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork p:))ne:7
|+''d
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 06
1=pV$CJ
QI<3N
1.0.dtd"> F*H}5yBp_:
R~([
<xwork> C]cw@:o%
>i<-rO>kN
<package name="user" extends="webwork- WdnP[x9
ozG:f*{T
interceptors"> eU0-_3gN_
[5-5tipvWp
<!-- The default interceptor stack name yFqC-t-i
gw^+[}U#
--> MIJ~j><L
<default-interceptor-ref ^DOcw@Z6HC
fZC,%p
name="myDefaultWebStack"/> Y#,MFEd
,vj^AXU
<action name="listUser" /zKuVaC
.S;/v--F
class="com.adt.action.user.ListUser"> 1g+<`1=KT
<param V}?5=f'
DEhA8.v
name="page.everyPage">10</param> lB-7.
<result n66_#X
=G :H)i
name="success">/user/user_list.jsp</result> v;7u"9t
</action> <}%*4mv
DFMWgBL
</package> W#Z]mt B
)ej8vm
</xwork> I5,Fh>
b;vO`
YzqhFFaj.
V
Euv
D6pk!mS
Z)~2{)
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 "u/8
$9/r*@bu8d
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。 $}@ll^
Yc}b&
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 WD:5C3;
9 )qx0
V'B 6C#jT
FgxQ}VvlH
s#ykD{Z
我写的一个用于分页的类,用了泛型了,hoho v)06`G
l3,|r QD
java代码: 3 0Z;}<)9
P%c<0y"O:>
vEkz5$
package com.intokr.util; rcOmpgew
~p.23G]x
import java.util.List; R\^tr
LCtm@oN
/** Ue7~rPdlR
* 用于分页的类<br> '4iu0ie>D
* 可以用于传递查询的结果也可以用于传送查询的参数<br> Jx]`!dP3
* U\N`[k.F
* @version 0.01 i \~4W$4I
* @author cheng o9CB
,c7]
*/ (DU{o\=
public class Paginator<E> { _
i8}ld-
privateint count = 0; // 总记录数 9Z=Bs)-y.
privateint p = 1; // 页编号 w[iQndu
privateint num = 20; // 每页的记录数 WG,{:|!E
privateList<E> results = null; // 结果 IaB
A 2
#X+)
/** 6m9Z5:xG
* 结果总数 /D12N'VaE
*/ fg2}~02n
publicint getCount(){ A+'j@c\&!
return count; > 01k
u
} I/adzLQ
J
GdVSjNC
publicvoid setCount(int count){ d 9|u~3
this.count = count; PF~&!~S>W
} R!O'DM+
d;z`xy(C
/** 8m iIlB
* 本结果所在的页码,从1开始 +q1@,LxN
* J<2N~$
* @return Returns the pageNo. ]du pU"VV
*/ E?V:dr
publicint getP(){ ^>>Naid
return p; ?Gb
18m
} li'#< "R?'
Z1&8U=pax
/** \6o
~ i
* if(p<=0) p=1
d%<Uh(+:
* W\"cp[b
* @param p E4PP&'
*/ [30< 0
publicvoid setP(int p){ Gh j[nsoC~
if(p <= 0) /2c?+04+
p = 1; vR -/c
this.p = p; n`6vM4rM)
} v^vEaB
)gE:@3
/** 5i0<BZDTef
* 每页记录数量 B!:(*lF
*/ _M?:N:e
publicint getNum(){ GYBM]mW^ W
return num; {YkW5zC(L
} wi!Ml4Sb
pl%ag~i5
/** >o@WT kF]
* if(num<1) num=1 (t <Um
Vd
*/ 8u>E(Vmpu
publicvoid setNum(int num){ F](kU#3"S
if(num < 1) %FwLFo^v
num = 1; PffRV7qU0
this.num = num;
@>BFhH
} *w!H -*`
yd2ouCUV
/** 8g<3J-7Mm
* 获得总页数 ^ H'|iju
*/ $Uzc
publicint getPageNum(){ "B.l j)
return(count - 1) / num + 1; >LjvMj ]
} ~q<UE\H
TygRG+G-
/** >8ePx,+!
* 获得本页的开始编号,为 (p-1)*num+1 KNV$9&Z
*/ `A#r6+
publicint getStart(){ x.'O_7c0:
return(p - 1) * num + 1; oYu5]ry
} JMoWA0f
/0 zk &g
/** ^K3{6}]
* @return Returns the results. Q?vGg{>
*/ ifuVV Fov
publicList<E> getResults(){ 7-)Y\D
return results; )=~1m85+5B
} !x>P]j7A}Y
+&|WC2#
public void setResults(List<E> results){ zF{5!b
this.results = results; $"sf%{~
} <jV_J+#
KnlVZn[3t
public String toString(){ /<GygRs
StringBuilder buff = new StringBuilder GX\/2P7CZ
B;^7Yu0,
(); oSxHTbp?
buff.append("{"); .a$][Jny
buff.append("count:").append(count); Jyvc(~x
buff.append(",p:").append(p); y>|7'M*+
buff.append(",nump:").append(num);
BVG 3 T
buff.append(",results:").append Ry,jPw5<
vQztD_bX%
(results); `6UW?1_Z5
buff.append("}"); 9hcZbM]
return buff.toString(); ;gf^;%FK
} LTrn$k3}
1'M<{h<sP
} --y.q~d
I( pU_7mw
P*G&pitT