Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Vv4w?K
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 gwDQ@
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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 \kU0D
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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 &FF%VUfQJ
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分页支持类: ld8 E!t[
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java代码: iB;EV8E
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package com.javaeye.common.util; 'M>QA"*48E
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import java.util.List; 3-z;pk
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publicclass PaginationSupport { 1*\JqCR
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publicfinalstaticint PAGESIZE = 30; 4}@J]_]Z
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privateint pageSize = PAGESIZE; &~of]A
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privateList items; ?ACflU_k
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privateint totalCount; %UDz4?zx
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privateint[] indexes = newint[0]; XKD0n^L[
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privateint startIndex = 0; 36mp+}R#
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public PaginationSupport(List items, int U~8;y'
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totalCount){ @v^;,cu'8
setPageSize(PAGESIZE); -`nQa$N-
setTotalCount(totalCount); xE.K
setItems(items); NUBf>~_}
setStartIndex(0); -j1?lY
} Vmq:As^a
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public PaginationSupport(List items, int w U".^
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totalCount, int startIndex){ s8L=:hiSf)
setPageSize(PAGESIZE); 32nB9[l
setTotalCount(totalCount); a *?bnw?
setItems(items); nBw4YDR!
setStartIndex(startIndex); {~J'J $hn8
} coa+@g,w7#
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public PaginationSupport(List items, int L?_'OwaY
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totalCount, int pageSize, int startIndex){ = F*SAz
setPageSize(pageSize);
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setTotalCount(totalCount); }LK +w+h~
setItems(items); nn[OC=cDN
setStartIndex(startIndex); ?=zF]J:G1w
} A[W3.$s
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publicList getItems(){ 6Ih8~Hu
return items; g{|F<2rd[m
} \4$V;C/n,
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publicvoid setItems(List items){ .g/PWEr\I
this.items = items; 8@b,>l$
} |^l17veA@
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publicint getPageSize(){ mhh^kwW
return pageSize; P/%5J3_,
} yN-o?[o
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publicvoid setPageSize(int pageSize){ 2F5*C
this.pageSize = pageSize; %?<Y&t
} D,R"P }G
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publicint getTotalCount(){ imb.CYS74
return totalCount; okwkMd-yW
} i'bviD
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publicvoid setTotalCount(int totalCount){ ?2d! ^!9
if(totalCount > 0){ Z`jc*jgy
this.totalCount = totalCount; $2!|e,x
int count = totalCount / ;t6)(d4z?
}EJAC*W,
pageSize; s=KK)6T
if(totalCount % pageSize > 0) \%],pZsA ~
count++; tW$Di*h
indexes = newint[count]; dWKjVf
for(int i = 0; i < count; i++){ wE*o1.
indexes = pageSize * 9NXL8QmC8
MS Qz,nn
i; hYvWD.c}
} LIah'6qR
}else{ -_`dA^
this.totalCount = 0; ^9_4#Ep(
} _;zIH5 H
} 0NB5YQ8_]
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publicint[] getIndexes(){ T)CEcz
return indexes; Hl|EySno
} Nbyc,a[o
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publicvoid setIndexes(int[] indexes){ :,8eM{.Q
this.indexes = indexes; %DQ!#Nl*
} }c]u'a!4
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publicint getStartIndex(){
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return startIndex; w *Txc}
} i3dV2^O
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publicvoid setStartIndex(int startIndex){ ABG>W>H-S
if(totalCount <= 0) +$CO
this.startIndex = 0; @Jh;YDr`A
elseif(startIndex >= totalCount) !
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this.startIndex = indexes !'5t(Zw5
M[:},?ah0
[indexes.length - 1]; nqv#?>Z^OT
elseif(startIndex < 0) <jz\U7TBf
this.startIndex = 0; TBU.%3dEyI
else{ cedH#;V!j
this.startIndex = indexes p E56CM
+Rq7m]
[startIndex / pageSize]; 5^0K5R6GQf
} }uo.N
} n&fV^ x
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publicint getNextIndex(){ 8]2j*e0xV
int nextIndex = getStartIndex() + nq,P.~l
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pageSize; iS#m{1m$$
if(nextIndex >= totalCount) V|T3blG?D
return getStartIndex(); m2r%m
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else XKEbK\
return nextIndex; w=}R'O;k
} #- z(]Y,y
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publicint getPreviousIndex(){ "v[?`<53^l
int previousIndex = getStartIndex() - R) 'AI[la
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pageSize; B`;DAsmT
if(previousIndex < 0) =7P(T`j
return0; EwuBL6kN
else kFZjMchm A
return previousIndex; nv-_\M
} FZJyqqA$_
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} (.J8Q
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抽象业务类 dq
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java代码: ?:1)=I<A4
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/** @ZFU< e$!
* Created on 2005-7-12 n?z^"vv$i
*/ F?!
package com.javaeye.common.business; Kj`sq":Je0
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import java.io.Serializable; 8~s-@3J
import java.util.List; %\n&iRwDF
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import org.hibernate.Criteria; jpW(w($XL
import org.hibernate.HibernateException; #&jr9RB
import org.hibernate.Session;
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import org.hibernate.criterion.DetachedCriteria; i@|.1dWh
import org.hibernate.criterion.Projections; /qalj\ud
import .wv!;
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org.springframework.orm.hibernate3.HibernateCallback; Vy:MK9U2
import &ivPY
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org.springframework.orm.hibernate3.support.HibernateDaoS :.,3Zw{l
p<9e5`&I
upport; $={WtR
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import com.javaeye.common.util.PaginationSupport; ;"@FLq(n
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public abstract class AbstractManager extends :/
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HibernateDaoSupport { A t#'q>Dn
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privateboolean cacheQueries = false; 0- 'f1 1S
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privateString queryCacheRegion; c*"TmDY
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publicvoid setCacheQueries(boolean Q hHexr6
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cacheQueries){ +y Yv"J
this.cacheQueries = cacheQueries; (n~e2tZ/
} G)E#wh_S^
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publicvoid setQueryCacheRegion(String q;kN+NK64
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queryCacheRegion){ >iCkvQ
this.queryCacheRegion = :K)=Hf2y
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queryCacheRegion; |Gw[vY
} TZ7{cekQ
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publicvoid save(finalObject entity){ R":nG7o
getHibernateTemplate().save(entity); E!4Qc+.
} \c! LC4pE
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publicvoid persist(finalObject entity){ !0g+}
getHibernateTemplate().save(entity); U?6YY`A8
} <9S?wju4W'
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publicvoid update(finalObject entity){ %KeQp W
getHibernateTemplate().update(entity); {)t6DH#
} fWR]L47n
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publicvoid delete(finalObject entity){ sq_N!
getHibernateTemplate().delete(entity); "mAVkq~
} EX[X|"r
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publicObject load(finalClass entity, #=f ]"uM<
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finalSerializable id){
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return getHibernateTemplate().load $a6&OH/
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(entity, id); Z;@F.r
} _c|>m4+X
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publicObject get(finalClass entity, &50Kn[
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finalSerializable id){ HnVUG4yZTD
return getHibernateTemplate().get }Kq5!XJV9C
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(entity, id); YE5v~2
} o(~>a
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publicList findAll(finalClass entity){ R,A|"Q
return getHibernateTemplate().find("from fPHv|_XM>
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" + entity.getName()); +*g[hRw[
} qkv.,z"
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publicList findByNamedQuery(finalString 1uv"5`%s
=[`wyQe`_
namedQuery){ 9U58#
return getHibernateTemplate +=MO6}5T
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().findByNamedQuery(namedQuery); x}1(okc
} "twV3R
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publicList findByNamedQuery(finalString query, l~&efAJ-$
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finalObject parameter){ s.KJYP
return getHibernateTemplate N{P (ym2yR
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().findByNamedQuery(query, parameter); R]/F{Xs
} *ARro
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publicList findByNamedQuery(finalString query, r7*[k[^[^
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finalObject[] parameters){ pWps-e
return getHibernateTemplate ^gky i/z
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().findByNamedQuery(query, parameters); J~<:yBup}
} >g93Bj*
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publicList find(finalString query){ wGISb\rr
return getHibernateTemplate().find z]P |%
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(query); &.7\{q\(
} #)>>f
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publicList find(finalString query, finalObject [Bpgb57En
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parameter){ o?p) V^7
return getHibernateTemplate().find W
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(query, parameter); "VcGr#zW
} {Fb)Z"8]
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public PaginationSupport findPageByCriteria S*#y7YKI
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(final DetachedCriteria detachedCriteria){ ,=6Eju#P
return findPageByCriteria 2U|Nkm
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); <hy>NM@$
} \3)%p('
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public PaginationSupport findPageByCriteria &,$A7:
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(final DetachedCriteria detachedCriteria, finalint #M`ijN!Y
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startIndex){ )[nzmL*w
return findPageByCriteria S$JM01
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(detachedCriteria, PaginationSupport.PAGESIZE, y[r T5ed
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startIndex); pd7FU~-
} %&gx@ \v
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public PaginationSupport findPageByCriteria 3tLh{S?uJ
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(final DetachedCriteria detachedCriteria, finalint
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pageSize, SxH}/I|W
finalint startIndex){ UZ](X/
return(PaginationSupport) dOiy[4s
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getHibernateTemplate().execute(new HibernateCallback(){ =e._b 7P
publicObject doInHibernate 4G`YZZQ
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(Session session)throws HibernateException { g|r
Criteria criteria = E-"Jgq\aC
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detachedCriteria.getExecutableCriteria(session); K@>v|JD
int totalCount = <M\Z}2 d
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((Integer) criteria.setProjection(Projections.rowCount [yVU
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()).uniqueResult()).intValue(); J J3vC
criteria.setProjection fi,=z
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(null); hnY^Z_v!
List items = `o*eL Lk
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criteria.setFirstResult(startIndex).setMaxResults Icr'l$PE
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(pageSize).list(); {9=U6m^R2
PaginationSupport ps = 4a646jg)
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new PaginationSupport(items, totalCount, pageSize, }3i@5ctQ
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startIndex); h\ybh
return ps; ,~kMkBkl~
} zf S<X
}, true); /JfXK$`
} 2KzKNe(
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public List findAllByCriteria(final y1AS^'
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DetachedCriteria detachedCriteria){ N CsUC
return(List) getHibernateTemplate P$oa6`%l
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().execute(new HibernateCallback(){ p1D-Q7F
publicObject doInHibernate 6Q>w\@lF
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(Session session)throws HibernateException { Ln:
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Criteria criteria = ~/.&Z`ls
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detachedCriteria.getExecutableCriteria(session); E7D^6G&i
return criteria.list(); [n^___7
} O4#zsr:"
}, true); #&/*ll)
} k |Lm;g
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public int getCountByCriteria(final *X>rvAd3
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DetachedCriteria detachedCriteria){ ILpB:g
Integer count = (Integer) !XicX9n
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getHibernateTemplate().execute(new HibernateCallback(){ f Xq e7[
publicObject doInHibernate VT9$&\)>O
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(Session session)throws HibernateException { %NBD^gF
Criteria criteria = b9v Kux
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detachedCriteria.getExecutableCriteria(session); -OHG1"/
return IW46-;l7
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criteria.setProjection(Projections.rowCount jgYiuM3c\
*oPSkEA{
()).uniqueResult(); *kIJv?%_}
} +X&B'
}, true); emaNmpg
return count.intValue(); byMO&Lb*
} m1<B6*iG"
} 6xOR,p>E
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用户在web层构造查询条件detachedCriteria,和可选的 bT;C8i4b\H
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 IKU-
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PaginationSupport的实例ps。 dfrq8n]
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ps.getItems()得到已分页好的结果集 aB Yhk|Ei
ps.getIndexes()得到分页索引的数组 z(m*]kpL"
ps.getTotalCount()得到总结果数 h8h4)>:
ps.getStartIndex()当前分页索引 15zL,yo
ps.getNextIndex()下一页索引 o+nU {
ps.getPreviousIndex()上一页索引 qmK!d<4
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 n8iN/Y<%U
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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 & .#0jb1r
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一下代码重构了。 )jH"6my_
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我把原本我的做法也提供出来供大家讨论吧: U{;i 864:}
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首先,为了实现分页查询,我封装了一个Page类: sFGXW
java代码: |S4yol
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y /PEm)=Tt
/*Created on 2005-4-14*/ R~tv?hP
package org.flyware.util.page; "'PDreS
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/** P8TiB
* @author Joa }FFW,x
* 0nl)0|?Az
*/ l&C%oW
publicclass Page { b'ew
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j$Kubg(I5
/** imply if the page has previous page */ H8\N~>
privateboolean hasPrePage; FV^kOz
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/** imply if the page has next page */ Ck[Z(=b$$:
privateboolean hasNextPage; XjX<?W
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/** the number of every page */ :Z/ig%
privateint everyPage; K_My4>~Il
R{*p\;
/** the total page number */ T? =jKLPC
privateint totalPage; !E*-\}[
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/** the number of current page */ =XYfzR
privateint currentPage; |D^[]*cEH
m=n
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/** the begin index of the records by the current jm*v0kNy
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query */ %fxGdzu7.
privateint beginIndex; @c&)K^v8
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/** The default constructor */ *rqih_j0
public Page(){ D9Q%*DLd$_
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} #ocT4
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/** construct the page by everyPage , X|oCD
* @param everyPage Qs4Jl ;Y _
* */ Pl 5+Oo
public Page(int everyPage){ I]} MK?
this.everyPage = everyPage; HM<V$
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} AA@J~qd
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/** The whole constructor */ c[Y7tj%y
public Page(boolean hasPrePage, boolean hasNextPage, txliZ|.O
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int everyPage, int totalPage, id*UTY
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int currentPage, int beginIndex){ (3_2h4O
this.hasPrePage = hasPrePage; Ot(EDa9}IJ
this.hasNextPage = hasNextPage; ;}:"[B3$
this.everyPage = everyPage; Vg2s~ce{
this.totalPage = totalPage; /TpM#hkq/2
this.currentPage = currentPage; C
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this.beginIndex = beginIndex; gBresHrlH
} VCh%v -/
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/** Prr<:q
* @return Q%@l`V)Rs
* Returns the beginIndex. -B@jQg@
>
*/ :vc[ iZ
publicint getBeginIndex(){ l&E- H@Pe
return beginIndex; kigc+R
} G*Qk9bk9
V_0e/7}Ya
/** 3``$yWWg
* @param beginIndex !dmI}<@&k
* The beginIndex to set. cITQ,ah
*/ =TyN"0@
publicvoid setBeginIndex(int beginIndex){ 377$c;4F
this.beginIndex = beginIndex; -6Cxz./#yS
} vsLn@k3
utRvE(IbmV
/** l HZf'P_Wx
* @return (}bP`[@rX!
* Returns the currentPage. Lt=#tu&d
*/ ()XL}~I{!A
publicint getCurrentPage(){ b)
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return currentPage; l6)*u[}E
} {5_*tV<I
H@OYtPHGR
/** :m-HHWMN
* @param currentPage hX~IZ((Hi8
* The currentPage to set. `N2zeFG
*/ 'ApWYt
publicvoid setCurrentPage(int currentPage){ 5GC{)#4
this.currentPage = currentPage; 1<pbO:r
} `W{Ye=|[d#
b Kv9F@
/** b\H~Ot[i
* @return N'|zPFkg
* Returns the everyPage. G8eAj%88
*/ #jK{)%}mA
publicint getEveryPage(){ yQ6{-:`)
return everyPage; Hd6Qy {,*-
} Pxy(YMv
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/** dIMs{!
* @param everyPage P2 f~sx9
* The everyPage to set. A+:K!|w
*/ Rnun() plJ
publicvoid setEveryPage(int everyPage){ p4|:u[:&
this.everyPage = everyPage; [WC-EDO2lb
} v5 $"v?PT
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/** bV`Zo(z
* @return #%B1,.A
* Returns the hasNextPage. X]Sr]M^EK
*/ rVFAwbR
publicboolean getHasNextPage(){ a+,)rY9
return hasNextPage; 6BNOF66kH
} RG #
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/** 2"JIlS;J}7
* @param hasNextPage x~A""*B~
* The hasNextPage to set. WWHT;ST
*/ prhFA3
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publicvoid setHasNextPage(boolean hasNextPage){ 8_m dh +
this.hasNextPage = hasNextPage; ^MDBJ0
I.
} ) Q]kUG#`
;. /Tv84I^
/** v!K%\h2A
* @return \O72PC+
* Returns the hasPrePage. }JAg<qy}
*/ $OmcEd
publicboolean getHasPrePage(){ dt^yEapjM
return hasPrePage; ATH0n>)
} cfa#a!Y4
W!V06.
/** 9:4P7
* @param hasPrePage x1?p+
* The hasPrePage to set. ?Tt/,Hl?D
*/ /V-7 u
publicvoid setHasPrePage(boolean hasPrePage){ Wvmf[!V;
this.hasPrePage = hasPrePage; 2u/(Q>#
} s%;18V:pi
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/** C5 ^_R
* @return Returns the totalPage. s
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* C`7HC2Is
*/ 6HFA2~A
publicint getTotalPage(){ XOVZ'V
return totalPage; l*xA5ObV
} u*}6)=+:
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/** Z9 }qds6 y
* @param totalPage sm4@ywd>
* The totalPage to set. NM
*/ |&h!#Q{7l
publicvoid setTotalPage(int totalPage){ dV.)+X7<
this.totalPage = totalPage; [}}oHm3&
} \D>'
#](ML:!
} U7bG(?k)
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bP(V#6IJ8
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 ]oXd|[G
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个PageUtil,负责对Page对象进行构造: Dbz\8gmY
java代码: o!wz:|\S
%`-NWAXL
nS]/=xP{
/*Created on 2005-4-14*/ BDD^*Y
package org.flyware.util.page; ,N5Rdgzk
&h8+-
import org.apache.commons.logging.Log; -L</,>p
import org.apache.commons.logging.LogFactory; cD-\fRBGK
Vy&F{T;$
/** eW0:&*.vMj
* @author Joa 2m/1:5
* |#f
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*/ Z:)\j.
publicclass PageUtil { 7Ja^d-F7
DTAEfs!ZW
privatestaticfinal Log logger = LogFactory.getLog jKM-(s!(
VDCrFZ!]
(PageUtil.class); *M6M'>Tin
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/** E':y3T@."
* Use the origin page to create a new page (gs"2
* @param page H /*^$>0Uo
* @param totalRecords ?gH[tN:=
* @return 0JKbp*H
*/ /p?h@6h@y
publicstatic Page createPage(Page page, int R8O<}>3a
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totalRecords){ ?Ju=L|
return createPage(page.getEveryPage(), C Vyq/X
dD@T}^j *|
page.getCurrentPage(), totalRecords); sW@4r/F>:D
} UOT~L4G
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/** 'hg, W]
* the basic page utils not including exception <b{Le{QJ*
+q1
@8
handler /XtxgO\T.
* @param everyPage xAon:58m{
* @param currentPage *`=V"nXw$|
* @param totalRecords
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* @return page NrhU70y
*/ #0hX)7(j
publicstatic Page createPage(int everyPage, int w!8h4U.
;
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currentPage, int totalRecords){ X];a(7+2
everyPage = getEveryPage(everyPage); &&Vz=6N
currentPage = getCurrentPage(currentPage); N}pE{~Y
int beginIndex = getBeginIndex(everyPage, By:A9s
oC^-" (#
currentPage); rM_8piD
int totalPage = getTotalPage(everyPage, ^mkplp
a
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totalRecords); |!flR? OU
boolean hasNextPage = hasNextPage(currentPage, .lOEQLt
11%^K=dq
totalPage); $ [M8G
boolean hasPrePage = hasPrePage(currentPage); Cf@WjgR
mVP@c&1w?
returnnew Page(hasPrePage, hasNextPage, \
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everyPage, totalPage, 0Eo*C9FP~
currentPage, 57%:0loW
wvBJ?t,
beginIndex); ^#vWdOlt
} C(xdiQJh
Qm^N}>e
privatestaticint getEveryPage(int everyPage){ ERCW5b[RT
return everyPage == 0 ? 10 : everyPage; n)^B0DnIk
} li$(oA2
G'#a&6
privatestaticint getCurrentPage(int currentPage){ CQ"5bnR
return currentPage == 0 ? 1 : currentPage; drNfFx2
} =cX&H
oju4.1
privatestaticint getBeginIndex(int everyPage, int 7:9WiN5b
"qMd%RP
currentPage){ Y GvtG U-
return(currentPage - 1) * everyPage; }+,1G!?z
} )LKutN?tBy
Y{f;qbEQH'
privatestaticint getTotalPage(int everyPage, int $
[0
+p>tO\mo
totalRecords){ 4B^f"6'
int totalPage = 0; AW%^Xt
]M-j_("&
if(totalRecords % everyPage == 0) /2~qm/%Q
totalPage = totalRecords / everyPage; f0O"Hm$Z
else lk)38.
totalPage = totalRecords / everyPage + 1 ; nH/V2>Lm
1vx:`2 A4
return totalPage; 9p9:nx\
} eM*@}3
cK1r9ED|
privatestaticboolean hasPrePage(int currentPage){ Bd31>
%6
return currentPage == 1 ? false : true; doW_vu
} 5O]ph[7
at/bes W
privatestaticboolean hasNextPage(int currentPage, I[c/)
N
PZ
AyHXY
int totalPage){ P!0uAkt9C
return currentPage == totalPage || totalPage == CRw.UC\
6zaO$
0 ? false : true; ZdY:I;)s
} z|<6y~5,
wS hsu_(i
7??+8T#n*
} ,_F1g<^@u
-'*B%yy
N0vr>e`
K*d+pImrV
Vyf r>pgW1
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。 Pz:,q~
LW{7|g
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 9V9K3xWn
_RST[B.u6
做法如下: zL+jlUkE
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 !w(J]<
gC>
A*~J;
的信息,和一个结果集List: Cz#0Gh>1
java代码: xKv\z1ra
,KdDowc
4`7N}$j#,
/*Created on 2005-6-13*/ "fU=W|lY
package com.adt.bo; to|O]h2*U2
`gDpb.=Y
import java.util.List; }N&}6U
H"=%|/1M0
import org.flyware.util.page.Page; kD8$ir'UYG
.-awl1 W
/** 9i;%(b{
* @author Joa N>/!e787OU
*/ ;xS@-</:
publicclass Result { P\pHos
^mv F%"g
private Page page; W.'#pd
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private List content; wa\Yc,R
}~DlOvsq
/** 8iGS=M
* The default constructor ^<}9#q/rt
*/ ;}@.E@s%'
public Result(){
{^a"T'+
super(); FAX|.!US*p
} sf<S#;aYqn
M ~zA
/** !ow:P8K?
* The constructor using fields 07P/A^Mkx
* {E@Fk,
* @param page LP-~;
* @param content HIsIW%B
*/ .!e):&(8
public Result(Page page, List content){ O3/][\
this.page = page; A<fKO <d
this.content = content; 'y[74?1
} I8TqK
MKf|(6;~
/** ?x1sm"]p'
* @return Returns the content. _~/F-
*/ SR!EQ<
publicList getContent(){ _2xNio&
return content; -K eoq
} Kkcb'aDR
m!Cvd9X=
/** }Go?j#
!
* @return Returns the page. d,8L-pT$FM
*/ ' ^E7T'v%
public Page getPage(){ VHyH't_&s
return page; X'Q?Mh
} e=Ko4Ao2y
<`rmQ`(}s
/** %A64AJZ
* @param content KSDz3qe
* The content to set. b+Sq[
*/ `?E|frz[
public void setContent(List content){ `?f6~$1
this.content = content; +O"!*
} Zgy~Y0Di
_N)/X|=~s
/** .);~H#
* @param page >9dzl#
* The page to set. 17P5Dr&
*/ |>|f?^
publicvoid setPage(Page page){ D+m#_'ocL
this.page = page; HVjN<H IqM
} C# zYZ JZ
} M$_E:u&D
5|O~
jV{?.0/h|
|?v(?
!z?&
2. 编写业务逻辑接口,并实现它(UserManager, + OKk~GYf
k;/K']4y
UserManagerImpl) TWE>"8]
java代码: 2iM]t&^<+
dhrh "x_?:
vT@*o=I
/*Created on 2005-7-15*/ ;>hRj!
package com.adt.service; corNw+|/w
c"KN;9c,
import net.sf.hibernate.HibernateException; ,5V w^@F
O|K-UTWH%
import org.flyware.util.page.Page; MrjgV+P}[
&3gC&b^i
import com.adt.bo.Result; CWT#1L=
]2E#P.-!b
/** +MZsL7%
* @author Joa dCA| )
*/ 9K!kU6Gh
publicinterface UserManager { zUuOX5-6x
_E %!5u
public Result listUser(Page page)throws |7%has3"
Ec/&?|$
HibernateException; .*}!XKp0j
^?M# |>
} )[b\wrc
='A VI-go5
<+y%k~("
mH.c`*
wqxChTbs
java代码: 0oK_u Y
4g
>}T}^F
ygK@\JHn
/*Created on 2005-7-15*/ 3vXa#f>P<
package com.adt.service.impl; kB`
@M>[
e"#QUc(
import java.util.List; niA>afo
1.0:
import net.sf.hibernate.HibernateException; a =
*'
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import org.flyware.util.page.Page; 'm=TBNQTS
import org.flyware.util.page.PageUtil; A"tE~m;"7
o5B]? ekpq
import com.adt.bo.Result; 6Y`rQ/F
import com.adt.dao.UserDAO; 7Pe<0K)s(
import com.adt.exception.ObjectNotFoundException; ~nJ"#Q_T
import com.adt.service.UserManager; k"3@G?JY
;!S i_b2
/** @.&KRAZ
* @author Joa shgZru
*/ t|urvoz
publicclass UserManagerImpl implements UserManager { ~6A;H$dr
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private UserDAO userDAO; !C(U9p. 0
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/**
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* @param userDAO The userDAO to set. R ;k1(p
*/ VUon>XQ
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publicvoid setUserDAO(UserDAO userDAO){ VTUSM{TC
this.userDAO = userDAO; uc{s\_
} R
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7}1Z7"?
/* (non-Javadoc) Tnv,$KOhs
* @see com.adt.service.UserManager#listUser BUCPO}I
'4Drs}j5
(org.flyware.util.page.Page) P3!JA)p6a
*/ `pb=y}
public Result listUser(Page page)throws D\^mh{q(
`]`S"W7&
HibernateException, ObjectNotFoundException { U?%T~!
int totalRecords = userDAO.getUserCount(); z"nMR_TTu
if(totalRecords == 0) iNs@8<=$T
throw new ObjectNotFoundException VS\| f'E
cG"wj$'w
("userNotExist"); *(s0X[-
page = PageUtil.createPage(page, totalRecords); 00B,1Q HP
List users = userDAO.getUserByPage(page); 82)%`$yZw[
returnnew Result(page, users); e'yw8U5E/
} g@'2 :'\
>*/:"!u
} }Ug$d>\
+~>cAWZq_
j[,XJ,5=
\kZ@2.pN
$."DOZQ3U
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ekW#|
2:RFPK
询,接下来编写UserDAO的代码: H:nO\]
3. UserDAO 和 UserDAOImpl: ce3``W/H3
java代码: rf^u&f
u9{SG^
s)jNP\-
/*Created on 2005-7-15*/ 75pn1*"gQ
package com.adt.dao; *JRM(V+IEv
jR9;<qT/
import java.util.List; #kk5{*`
]u^ybW"
import org.flyware.util.page.Page; O]Ey@7 &
JXV#V7
import net.sf.hibernate.HibernateException; ev#/v:$?
jM-7
/** @QMU$]&i]
* @author Joa Y <`X$
*/ "Lyb4# M
publicinterface UserDAO extends BaseDAO { e(?1`1
i[4!% FxB
publicList getUserByName(String name)throws {Hie%2V
r $[{sW
HibernateException; iGSF5S
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publicint getUserCount()throws HibernateException; vmv6y*qU
Scug
wSB
publicList getUserByPage(Page page)throws 3&I3ViAH
Rh!m1Q(-
HibernateException; 2Lytk OMf
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} 0dIGX |e
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+f$
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1,:QrhC
java代码: ,k1ns?i9KH
p-m\0tQ
G)?j(El
/*Created on 2005-7-15*/ R_9M-RP6*
package com.adt.dao.impl; ]*U+nG
9@?|rje9
import java.util.List; b'C#]DorE
H2xDC_Fs
import org.flyware.util.page.Page; V*r/0|vd
E@%1HO_
import net.sf.hibernate.HibernateException; L{GlDoFk
import net.sf.hibernate.Query; Z<W f/
;s #I b_
import com.adt.dao.UserDAO; i1X!G|Awfv
L8f_^
*,
/** z}iz~WZ
* @author Joa vM-kk:n7f
*/ y<*\D_J
public class UserDAOImpl extends BaseDAOHibernateImpl Q@|"xKa
>sdF:(JV&
implements UserDAO { #S]O|$&*
*%\Xw*\0
/* (non-Javadoc) Xgl
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* @see com.adt.dao.UserDAO#getUserByName mhM;`dl
Y
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(java.lang.String) M?Fv'YE
*/ Lp3pJE
publicList getUserByName(String name)throws W9{;HGWS
=jA.INin4
HibernateException { >0u*E *Y
String querySentence = "FROM user in class Q"Exmn3p
~.6% %1?
com.adt.po.User WHERE user.name=:name"; c}!`tBTm
Query query = getSession().createQuery g6xQQ,q=l
4=%,0.yt
(querySentence); {t4':{Y+
query.setParameter("name", name); O2"@09:
return query.list(); xXnSo0`LF
} (#x&Y#5
@Z7s3b
/* (non-Javadoc) nET<u;
* @see com.adt.dao.UserDAO#getUserCount() Bio QV47B
*/ _v8u%
publicint getUserCount()throws HibernateException { bMsThoePT
int count = 0; 5z_Kkf?o
String querySentence = "SELECT count(*) FROM @+_pj.D
gK"(;Jih$
user in class com.adt.po.User"; G^z>2P
Query query = getSession().createQuery ,Y#f0
UV</Nx)3
(querySentence); APJFy@l}
count = ((Integer)query.iterate().next *3h_'3yo@
0C3Y =F
()).intValue(); Q<DXDvL
return count; >s!k"s,
} g~(G P
asE.!g?
/* (non-Javadoc)
z).&0K
* @see com.adt.dao.UserDAO#getUserByPage QxuU3#l
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(org.flyware.util.page.Page) Gm> =s
*/ I~E&::,
publicList getUserByPage(Page page)throws &|h9L' mr
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HibernateException { X{[$4\di{
String querySentence = "FROM user in class ug'^$geM
E(z|LS*3
com.adt.po.User"; kpy)kS
Query query = getSession().createQuery <[T{q
|*
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(querySentence); #)i+'L8
query.setFirstResult(page.getBeginIndex()) '
QjJ^3A
.setMaxResults(page.getEveryPage()); #s#BYbF
return query.list(); {$pi};
} 4H@7t,>
b7">IzAe
} 5|`./+Ghk
pV!WZUfg
2|(lKFkQ
"\]]?&
eht>4)
至此,一个完整的分页程序完成。前台的只需要调用 ;>fM?ae5
snNB;hkj
userManager.listUser(page)即可得到一个Page对象和结果集对象 ;TK$?hrv*1
*(XGNp[0
的综合体,而传入的参数page对象则可以由前台传入,如果用 bPkz= ^-
@k# xr
webwork,甚至可以直接在配置文件中指定。 T1 1>&K)
Q ~n%c7
下面给出一个webwork调用示例: 3hEbM'L
java代码: KdzV^6K<c
>wFn|7\)s>
]r%fAmj
/*Created on 2005-6-17*/ 3qDbfO[
package com.adt.action.user; Ls3r( Tf
&m]jYvRc
import java.util.List; ;?TM_%>
V&/Cb&~Uw
import org.apache.commons.logging.Log; e~9g~k]s
import org.apache.commons.logging.LogFactory; FF7?|V!Q
import org.flyware.util.page.Page; :~ 	
tO D}&
import com.adt.bo.Result; fQ-IM/z
import com.adt.service.UserService; *+00
import com.opensymphony.xwork.Action; oMYZ^b^
OHnsfXO_V
/** glkH??S
* @author Joa 7j(gW
*/ aZ|S$-}
publicclass ListUser implementsAction{ W[e2J&G
bweAmSs
privatestaticfinal Log logger = LogFactory.getLog 5d# 73)x$
^&c &5S}
(ListUser.class); ~fzuz'"^
TN08,:k
private UserService userService; <^W5UU#Pg
F}@]Lq+
private Page page; )jjaY1E
H;DjM;be
privateList users; ^X"x,8}&V
A!uiM*"W
/* Jp_ :.4
* (non-Javadoc) r
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* jfam/LL{V
* @see com.opensymphony.xwork.Action#execute() {d)L0KXK
*/ hvA|d=R(
publicString execute()throwsException{ m%.[|sZ3EM
Result result = userService.listUser(page); gO@LJ
page = result.getPage(); uu>R)iTQ%S
users = result.getContent(); Zw<<p|{)<
return SUCCESS; <^942y-=
} 9T1-{s
R
3;!!`R>e
/** MOi1+`kwh
* @return Returns the page. :2XX~|
*/ sv#b5,>9
public Page getPage(){ s"2+H}u
return page; g0IvcA
} VCIV*5
P
NQcg}y
/** hx4c`fOs
* @return Returns the users. 5aXE^.`
*/ +=nWB=iCb
publicList getUsers(){ `7?EE1o
return users; Q~rE+?n9F
} 41Ab,
m6A\R KJ'
/** 6.[3N~pq
* @param page ;hEeFJ=/G
* The page to set. 1F+JyZK}w
*/ )@=fGN Dt
publicvoid setPage(Page page){ [dqh-7
this.page = page; ''q#zEf6
} L!`PM.:9
!HP=Rgh
/** U8,pe;/ln`
* @param users dOKe}?}==
* The users to set. Q|U
[|U
*/ kQn}lD
publicvoid setUsers(List users){ Lzcea+*uw
this.users = users; ~]n=TEJ>
} 1qm*#4x
9;L8%T
(
/** K<5 0>uG
* @param userService r8[)C cv
* The userService to set. XK)0Mt\
*/ !!cN4X
publicvoid setUserService(UserService userService){ [h8macx
this.userService = userService; vY,D02EMw
}
\]dvwN3x
} ,rNud]NM8
hf7[<I,jov
+%K~HYN
o*oFCR]j
.kgt?r
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, X!@ Y,
"M^mJl&*b
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 2h)Qz+|7
}KEr@h,N
么只需要: *u < ZQq
java代码: +/" \.wYv
,K|UUosS-#
2zuQeFsK
<?xml version="1.0"?> Yvu?M8aK!
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ,/!^ZS*
#u +~ ^M
1.0//EN" "http://www.opensymphony.com/xwork/xwork- HuQdQ*Q
vTIRydg2b
1.0.dtd"> t
>.=q:
1jaK N*
<xwork> cIP%t pTW.
+*aC
\4w
<package name="user" extends="webwork- e{*yV#Wl
;<nJBZB9u
interceptors"> @Qp#Tg<'
Gi*_ &
<!-- The default interceptor stack name Hxleh><c-
?I\,RiZkz^
--> %36@1l-N
<default-interceptor-ref #q xo1uV(c
r d)W+W9
name="myDefaultWebStack"/> u1\r:q
H5o=nWQ6e
<action name="listUser"
;kT~&.,y
6&
6|R3
class="com.adt.action.user.ListUser">
o^r\7g6\
<param v2="j
'E\4/0 !
name="page.everyPage">10</param> su3Wk,MLP
<result xJA{Hws
oArJ%Y>
name="success">/user/user_list.jsp</result> w6pXF5ur>
</action> ff~1>=^
~qK/w0=j
</package> \)ZCB7|
}<*KM)%
</xwork> tf[)| /M
3Vak
C
i4XiwjCHN
k|U2Mp
pbw{EzM
{-%8RSK=<
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%\&n0
?/myG{E
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。 8pZ Ogh
bR8`Y(=F9b
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 NOKU2d4 G
yqB!0)
<
H8 xhE~'t
%.onO0})
7+qKA1t^
我写的一个用于分页的类,用了泛型了,hoho ''3I0X*!
Wrh$`JC
java代码: ?0?3yD-!9
[1 O{yPV3s
X;
6=WqJj
package com.intokr.util; ,i8%qm8
B&6lG!K'?
import java.util.List; |68k9rq
7!\zo mx
/** |=MhI5gsx
* 用于分页的类<br> vo%"(!
* 可以用于传递查询的结果也可以用于传送查询的参数<br> IDL0!cF
* "\=Phqw
* @version 0.01 HxcL3Bh$~}
* @author cheng M>}_2G]#F
*/ Qkhor-f0
public class Paginator<E> { $48Z>ij?f
privateint count = 0; // 总记录数 D3%2O`9
privateint p = 1; // 页编号 1Kd6tnX
privateint num = 20; // 每页的记录数 mrr~ #Bb>
privateList<E> results = null; // 结果 1 vtC4`
|qz%6w=
/** f8`dJ5i
* 结果总数 n9n)eI)R
*/ p@[ fZj
publicint getCount(){ <fV][W
return count; yc`*zLWh
} q6<P\CSHy<
_uXb>V*8
publicvoid setCount(int count){ J_.cC
this.count = count; b&dv("e
4
} -Mz [S
DUh\x>^
/** Ez-Q'v(9
* 本结果所在的页码,从1开始 w~ON861
* $2RSYI`py
* @return Returns the pageNo. lW|v_oP9
*/ Aa4Tq2G
publicint getP(){ j4+Px%sW
return p; R<(xWH
} 4 Tw~4b
>[;=c0(
/** $*T?}r>
* if(p<=0) p=1 >P&1or)e%
* 1@Ju sS0^K
* @param p $EX(-!c
*/ _(I6o
publicvoid setP(int p){ R=F_U
if(p <= 0) 0U H]
p = 1; \4^rb?B
this.p = p; (<8}un
} c?u*,d) G
RS
l*u[fB
/** M.r7^9 P
* 每页记录数量 w( _42)v]g
*/ ZfK[o{9>
publicint getNum(){ ! ?/:p.
return num; P^48]Kj7
} 7 )rL<+
_53~D=
/** mt`CQz"_
* if(num<1) num=1 RHMXPsj
*/ Lj9RF<39g
publicvoid setNum(int num){ eZN"t~\rX
if(num < 1) "H<us?r{
num = 1; k)|.<
this.num = num; ;i'[c`
} Z7RBJK7|.
:GO"bsjL
/** LO>42o?/i
* 获得总页数 WmN(
(
*/ A`ajsZ{q,
publicint getPageNum(){ -]H~D4ng
return(count - 1) / num + 1; " aCAA#$J
} BP0:<vK{
-Ou.C7ol
/** tiHR&v
* 获得本页的开始编号,为 (p-1)*num+1 q$mc{F($D
*/ ]z/R?SM
publicint getStart(){ "\KBF
return(p - 1) * num + 1; IA({RE
} =I)43ahd
~~ rR< re
/** !hhL",
* @return Returns the results. ~rJG4U
*/ |E.BGdS
publicList<E> getResults(){ [nP s
return results; XW" 0:}`J
} ]|+M0:2?
9|#cjHf
public void setResults(List<E> results){ kuV7nsXiQ
this.results = results; ``Q6R2[|)
} ;'= cNj
c$%*p
(zY
public String toString(){ nGkSS_X
StringBuilder buff = new StringBuilder =@?[.`
%&|
uT
(); R]iV;j|
buff.append("{"); ,1$F#Eh
buff.append("count:").append(count); LzNfMvh
buff.append(",p:").append(p); G+t:]\
buff.append(",nump:").append(num); %dFJ'[jDL
buff.append(",results:").append ng"=vmu
?(R3%fU
(results); Es%f@$0uy
buff.append("}"); qul#)HI
return buff.toString(); dkZe.pv$j
} >m,hna]RZ
U5OX.0
} pUb1#=
^hmV?a:Y
U`mX
f#D