Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 9;n*u9<
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 pi70^`@ 'B
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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 | Wj=%Ol%o
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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 zSMM?g^T
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分页支持类: 37IHn6r\
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java代码: K}n.k[Do
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package com.javaeye.common.util; li{<F{7
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import java.util.List; Vnb@5W2\
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publicclass PaginationSupport { m'G=WO*%
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publicfinalstaticint PAGESIZE = 30; 4S+E%b|)
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privateint pageSize = PAGESIZE; SMd[*9l
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privateList items; MkdC*|
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privateint totalCount; g rI#' x
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privateint[] indexes = newint[0]; k^KpQ&n
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privateint startIndex = 0; ^G5 fs'd
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public PaginationSupport(List items, int EKw)\T1
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totalCount){ z 36Y/{>[
setPageSize(PAGESIZE); Uw5&.aqn.b
setTotalCount(totalCount); 7bGOE_r
setItems(items); a>6M{C@pd
setStartIndex(0); Mx# P
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} V'za,.d-
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public PaginationSupport(List items, int /r&4< @
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totalCount, int startIndex){ |Ul 4n@+2
setPageSize(PAGESIZE); 8t7r^[T
setTotalCount(totalCount); &liFUP?
setItems(items); 1Qjc*+JzO.
setStartIndex(startIndex); vUL@i'0&o
} S@
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public PaginationSupport(List items, int x a\~(B.
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totalCount, int pageSize, int startIndex){ 2>J;P C[;
setPageSize(pageSize); XfEp_.~JM
setTotalCount(totalCount); )\W}&9 >
setItems(items); 6Y.k<oem
setStartIndex(startIndex); LF(S"Of
} ,#^2t_c/
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publicList getItems(){ %rl<%%T#.M
return items; KAT"!b
} TL-ALtG
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publicvoid setItems(List items){ V.+a}J=Cw
this.items = items; W=#jtU`:5
} gId
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publicint getPageSize(){ nkN2Bqt$
return pageSize; C(KV5c
} wk=s3^
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publicvoid setPageSize(int pageSize){ }\A0g}
this.pageSize = pageSize; uc=u4@.>
} pJo4&Ff
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publicint getTotalCount(){ )wEXCXr!
return totalCount; dry%aT
} v9gaRqi8
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publicvoid setTotalCount(int totalCount){ Tjj27+y*\
if(totalCount > 0){ =*UVe%N4
this.totalCount = totalCount; HuxvIg
int count = totalCount / 'I[xZu/8yg
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pageSize; !_dW
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if(totalCount % pageSize > 0) {=Py|N\\t
count++; pUgas?e&
indexes = newint[count]; q #8z%/~k
for(int i = 0; i < count; i++){ !:_krLB<
indexes = pageSize * !l9#a{#6l
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i; XNBzA3W
} GIK.+kn\
}else{ ?]}=4
this.totalCount = 0; D{+D.4\
} 1P BnGQYM
} ((BdT:T\_
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publicint[] getIndexes(){ 4i29nq^n
return indexes; ,M\/[_:
} dVJ9cJ9^
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publicvoid setIndexes(int[] indexes){ +xr;X 9
this.indexes = indexes; v=IcVHuf
} h}+Gz={Q^
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publicint getStartIndex(){ K=P LOC5
return startIndex; 1u*
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} X(]J\?n'
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publicvoid setStartIndex(int startIndex){ a
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if(totalCount <= 0) BK.RYSN
this.startIndex = 0; "(a}}q 9-
elseif(startIndex >= totalCount) )9!J
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this.startIndex = indexes You~
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[indexes.length - 1]; L$ju~0jl)%
elseif(startIndex < 0) DVBsRV)/
this.startIndex = 0; MR* %lZpB
else{ (Q|Y*yI
this.startIndex = indexes woU3WS0
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[startIndex / pageSize]; 8PGuZw<
} ;s-fYS6(>{
} 4DGKZh'm"
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publicint getNextIndex(){ oIKuo~
int nextIndex = getStartIndex() + kChCo0Q>1
uD`Z\@Z
pageSize; hnv0Loe.IW
if(nextIndex >= totalCount) DH4|lb}
return getStartIndex(); FJB
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else ~HBx5Cpi
return nextIndex; %bhFl,tL
} >>>MTV f
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publicint getPreviousIndex(){ sDy~<$l?
int previousIndex = getStartIndex() - MIc(B_q
j)jt&Gg'
pageSize; x=Ez hq]X
if(previousIndex < 0) K$
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return0; ~A>-tn}O
else >DR/lBtL
return previousIndex; u%CJjy
} PO0/C q)
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} 3,@|kN<
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抽象业务类 `$r?^|T
java代码: PW-sF
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/** CSE!Abg
* Created on 2005-7-12 w"h'rw
*/ m^a0JR}u9
package com.javaeye.common.business; EJTa~
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import java.io.Serializable; h56s ~(?O
import java.util.List; G*^4CJ
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import org.hibernate.Criteria; x1QL!MB
import org.hibernate.HibernateException; Ua>.k|>0
import org.hibernate.Session; ?D=%k8)Y
import org.hibernate.criterion.DetachedCriteria; d%ncI0f`
import org.hibernate.criterion.Projections; au7@- _
import S2
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org.springframework.orm.hibernate3.HibernateCallback; d|$-l:(J
import +PHuQ
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org.springframework.orm.hibernate3.support.HibernateDaoS EaN^<
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upport; ch0x*[N@
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import com.javaeye.common.util.PaginationSupport; (FNX>2Mv
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public abstract class AbstractManager extends (7}Zh|@W
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HibernateDaoSupport { vb k4
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privateboolean cacheQueries = false; g+u5u\k
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privateString queryCacheRegion; unkA%x{W;
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publicvoid setCacheQueries(boolean qnU$Pd
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cacheQueries){ 1?#Wg>7'
this.cacheQueries = cacheQueries; X\]Dx./
} qk\LfRbj
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publicvoid setQueryCacheRegion(String -<gQ>`(0
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queryCacheRegion){ ut9R]01:
this.queryCacheRegion = <p8>"~R
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queryCacheRegion;
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} C=PV-Ul+
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publicvoid save(finalObject entity){ /Oa.@53tK6
getHibernateTemplate().save(entity); %'[ pucEF
} %Z#[{yuFs
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publicvoid persist(finalObject entity){ ^NOy:>
getHibernateTemplate().save(entity); =zKbvwe%X
} }{
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publicvoid update(finalObject entity){ h>jp.%oOu
getHibernateTemplate().update(entity); 3x~AaC.j
} 15`,kJSK
}zV#?;}
publicvoid delete(finalObject entity){ VufG7%S{
getHibernateTemplate().delete(entity); .[X"+i\
} 3O'X;s2\d
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publicObject load(finalClass entity, -*&C "%e
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finalSerializable id){ -;o`(3wZq
return getHibernateTemplate().load b'yW+
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(entity, id); .aqP=
} =J&aN1Hgt
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publicObject get(finalClass entity, vke]VXU9z
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finalSerializable id){ 9IG3zM f
return getHibernateTemplate().get G@Vz
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(entity, id); l j*J|%~
} +\`t@Ht#
h}(GOYS)
publicList findAll(finalClass entity){ t%>x}b"2T
return getHibernateTemplate().find("from {:d9q
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" + entity.getName()); I~I$/j]e`
} O\qY?)
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publicList findByNamedQuery(finalString \%:]o-+"I
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namedQuery){ +S>}<OE
return getHibernateTemplate yzmwNsu
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().findByNamedQuery(namedQuery); 7u7 <"?v=
} /2PsC*y
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publicList findByNamedQuery(finalString query, #pw=HHq*(
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finalObject parameter){ B[Fuy y?
return getHibernateTemplate eFeWjB'<7
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().findByNamedQuery(query, parameter); az ?2
} {^n\
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publicList findByNamedQuery(finalString query, cxQ8/0^
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finalObject[] parameters){ -#?p16qz5
return getHibernateTemplate (Eoji7U
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().findByNamedQuery(query, parameters); 0Ku%9wh-
} HR83{B21
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publicList find(finalString query){ !56gJJ-r
return getHibernateTemplate().find A/"p PO
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(query); \V,;F!*#G
} &$</|F)y
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publicList find(finalString query, finalObject f~D>
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parameter){ <\cH9D`dE
return getHibernateTemplate().find Z"fnjH
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(query, parameter); MO$dim>
}
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public PaginationSupport findPageByCriteria kDG'5X;+
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(final DetachedCriteria detachedCriteria){ qm)KO 4
return findPageByCriteria 7E9h!<5v
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); sm>Hkci%
} afMIq Q?
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public PaginationSupport findPageByCriteria d>Z{TFY
*?+maK{5+
(final DetachedCriteria detachedCriteria, finalint Y(]&j`%
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startIndex){ #)BdN
return findPageByCriteria hFjXgpz5
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(detachedCriteria, PaginationSupport.PAGESIZE, vx\h
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startIndex); -R;.Md_
} WM}bM]oe
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public PaginationSupport findPageByCriteria Ek ,s6B)'d
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(final DetachedCriteria detachedCriteria, finalint 2Ax HhD.
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pageSize, {Z_Pry$6
finalint startIndex){ I/s?]v
return(PaginationSupport) /.\$%bua
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getHibernateTemplate().execute(new HibernateCallback(){ 8F<Qc*'
publicObject doInHibernate X3:-+]6,d
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(Session session)throws HibernateException { jz$)*Kdi*
Criteria criteria = -< 7KW0CA
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detachedCriteria.getExecutableCriteria(session); +*Cg2`
int totalCount = 8<t?o'9I
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((Integer) criteria.setProjection(Projections.rowCount eb)S<%R/
QH%{r4
()).uniqueResult()).intValue(); OwQ 9y<v
criteria.setProjection 3
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(null); gtHk1 9
List items = MQQ!@I`
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criteria.setFirstResult(startIndex).setMaxResults )^^r\
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(pageSize).list(); Z8=4cWI~;
PaginationSupport ps = [j5^Zb&0
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new PaginationSupport(items, totalCount, pageSize, %xR;8IO
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startIndex); `\&qk)ZP
return ps; 48n>[
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} w<awCp
}, true); N2}].}
} zu}h3n5
}tU<RvT
public List findAllByCriteria(final %t\`20-1<
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DetachedCriteria detachedCriteria){ 2D
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return(List) getHibernateTemplate ~2~KcgPsq
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().execute(new HibernateCallback(){ }d)>pH
publicObject doInHibernate Z\{WBUR;4t
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(Session session)throws HibernateException { CPGXwM=
Criteria criteria = e@L'H)w,
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detachedCriteria.getExecutableCriteria(session); 11
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return criteria.list(); nrA}36 E
} [6
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}, true); {61NLF\0H
} "wxs
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public int getCountByCriteria(final FI~)ZhE)]
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DetachedCriteria detachedCriteria){ HF5aU:M
Integer count = (Integer) Xig+[2zS
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getHibernateTemplate().execute(new HibernateCallback(){ ^$_a_ft#
publicObject doInHibernate 5in6Y5c kj
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(Session session)throws HibernateException { gW6lMyiLb
Criteria criteria = bs]ret$?(q
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detachedCriteria.getExecutableCriteria(session); T{|'<KT
return P,~a'_w:|D
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criteria.setProjection(Projections.rowCount PF!Q2t5c3
f b_tda",}
()).uniqueResult(); eF}Q8]da
} X<(h)&E
}, true); k KL^U
return count.intValue(); (J<@e!@NE
} Os8]iNvW\
} 8R:H{)o~s}
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用户在web层构造查询条件detachedCriteria,和可选的 3T Q#3h
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 *D,+v!wG9
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PaginationSupport的实例ps。 ,h5.Si>
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ps.getItems()得到已分页好的结果集 rQ*'2Zf'<
ps.getIndexes()得到分页索引的数组 Gr?"okaA
ps.getTotalCount()得到总结果数 C3bZ3vcW$
ps.getStartIndex()当前分页索引 ?GD{}f33
ps.getNextIndex()下一页索引 ozkN&0
ps.getPreviousIndex()上一页索引 rgIJ]vmy<H
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 / vje='[!
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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 p4Vw`i+DnH
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一下代码重构了。 ,$vc*}yI0
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我把原本我的做法也提供出来供大家讨论吧: x;Dr40wD@y
u/y`M]17
首先,为了实现分页查询,我封装了一个Page类: #&r^~>,#L-
java代码: AWQwpaj-
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/*Created on 2005-4-14*/ wXXv0OzK
package org.flyware.util.page; j^iH[pN] \
L\ _8}\
/** +#1WOQfAD
* @author Joa $./JA)`
* )J~Qx-jG
*/ I^M3>}p
publicclass Page { }
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A[ /0on5r
/** imply if the page has previous page */ '4dnC2a]
privateboolean hasPrePage; $hndb+6q
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/** imply if the page has next page */ <B$Lu4b@c
privateboolean hasNextPage; 9S&6u1
Mk|h ><Q"
/** the number of every page */ '$1-A%e$1
privateint everyPage; F2oY_mA
.b N0!
/** the total page number */ 8dIgw
privateint totalPage; i]hFiX
wOHK
dQ'
/** the number of current page */ wc~a}0uz
privateint currentPage; I.y|AQB
e#kPf 'gL
/** the begin index of the records by the current E;VW6[M
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query */ '9<Mk-Aj
privateint beginIndex; Ez<J+#)t
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/** The default constructor */ U G^6I5
public Page(){ a/_sL(F{
WF *2^iWJ
} OYG8%L
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/** construct the page by everyPage z>~`9Qiw'
* @param everyPage S:rW}r J
* */ RF g$N@g,
public Page(int everyPage){ nN@8vivP%
this.everyPage = everyPage; `U(A 5
} CXCU5-
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/** The whole constructor */ }Ax$}#
public Page(boolean hasPrePage, boolean hasNextPage, C&<f YCwG
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int everyPage, int totalPage, 4vBZb^W;9
int currentPage, int beginIndex){ ZwO&G\A^
this.hasPrePage = hasPrePage; n8zUL1:R
this.hasNextPage = hasNextPage; S5m1~fz
this.everyPage = everyPage; u"pn'H
this.totalPage = totalPage; j]Rl1~+M
this.currentPage = currentPage; 1vl~[
this.beginIndex = beginIndex; qYsu3y)*N
} Y/gVyQ(
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/** w4(DR?[nC
* @return w`>xK
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* Returns the beginIndex. (zJ
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*/ !R{L`T0
publicint getBeginIndex(){ 0lmoI4bW}s
return beginIndex; YfxZ<
} UvQxtT]
7OC,KgJ3
/** q G=`'%,m
* @param beginIndex 2R2Z6}
* The beginIndex to set. /=m=i%& #
*/ ?>RJ8\Sj
publicvoid setBeginIndex(int beginIndex){ wAk oX
this.beginIndex = beginIndex; TKRu^KH9
} w:MfaN*
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/** 2!]':(8mR
* @return !WVF{L,/I
* Returns the currentPage. ut-UTW
*/ gyI5;il~
publicint getCurrentPage(){ %@H;6
return currentPage; 4^AE;= Q
} a&XURyp
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/** ,p$1n;
* @param currentPage >K50 h
* The currentPage to set. Z"e|DP`
*/ >-y'N.l^
publicvoid setCurrentPage(int currentPage){ )
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this.currentPage = currentPage; .]v8W51Y
} lpSM p
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/** +Icg;m{
* @return ^BNg^V.
* Returns the everyPage. .f(x9|K^
*/
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publicint getEveryPage(){ 3b#KrN'
return everyPage; 8uT@$./
} bE]2:~
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/** uERc\TZ
* @param everyPage ]dk~C?H
* The everyPage to set. lW^RwNcd
*/ S1&6P)X.Za
publicvoid setEveryPage(int everyPage){ dLQ!hKD~
this.everyPage = everyPage; $stJ+uh
} J
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/** ^P&y9dC.
* @return p(U'c}@2
* Returns the hasNextPage. 'Ur$jW
*/ )W*S6}A
publicboolean getHasNextPage(){ 8#7z5:_
return hasNextPage; !\?? [1_e
} G'{4ec0<{
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/** /A<L
* @param hasNextPage 2,NQ(c_c$
* The hasNextPage to set. 6PvV X*5T
*/ c(YNv4*X
publicvoid setHasNextPage(boolean hasNextPage){ ,VJ0J!@
this.hasNextPage = hasNextPage; @Cw<wrem
} ,pf<"^li
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/** \J9@p
* @return oEKLuy
* Returns the hasPrePage. sbkWJy
*/ ,/o<O jR
publicboolean getHasPrePage(){ M@8
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return hasPrePage; ZIpL4y
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} H$1R\rE`
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/** MK~viSgi
* @param hasPrePage s:;!QIC5jo
* The hasPrePage to set. Ds0^/bYp&
*/ Cd6^aFoK!
publicvoid setHasPrePage(boolean hasPrePage){ LA"`8
this.hasPrePage = hasPrePage; Bv!j.$0d{
} /Pi{Mv eZM
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/** hua{g_
* @return Returns the totalPage. ;'R{b$B;|
* ~{U~9v^v(
*/ JsVW:8QO~
publicint getTotalPage(){ S
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return totalPage; #Du1(R
} oD~VK,.
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/** 3Yg/-=U(
* @param totalPage ^aXyho
* The totalPage to set. F!'b_gmz
*/ KQQR"[z&V
publicvoid setTotalPage(int totalPage){ 1 ljgq]($
this.totalPage = totalPage; SaQ_%-p
} vPSH
0'z$"(6D
} !*+~R2&b
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hD # Yz<
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 9s5CqB
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个PageUtil,负责对Page对象进行构造: (ioi !p
java代码: ~i6tcd
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/*Created on 2005-4-14*/ }& `#
package org.flyware.util.page; {$O.@#'
3EF|1B/5
import org.apache.commons.logging.Log; /`}C~
import org.apache.commons.logging.LogFactory; M,q'
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/** Q[`_Y3@j
* @author Joa QfT&y &
* YG"P:d;s
*/ &xrm;pO
publicclass PageUtil { FeLWQn/aV6
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privatestaticfinal Log logger = LogFactory.getLog _%z)Y=Q
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(PageUtil.class); jD$T
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/** v[35C]gS
* Use the origin page to create a new page u|O5ZV-cd
* @param page 2+
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* @param totalRecords Yz\z
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* @return l|U=(aA]h
*/ .5KRi6
publicstatic Page createPage(Page page, int "%-HZw%X
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totalRecords){ V:F)m!
return createPage(page.getEveryPage(), IWuR=I$t
VU}UK$JN
page.getCurrentPage(), totalRecords); +Rxf~m(pV
} m:II<tv
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/** pbR84g^p.S
* the basic page utils not including exception $PHKI B(
GkaIqBS
handler 2O`uzT$
* @param everyPage SYeCz(H>d
* @param currentPage 1MX:^L!f8
* @param totalRecords zrD$loaW.'
* @return page V5qvH"^
*/ 2EycFjO
publicstatic Page createPage(int everyPage, int pkjL2U:
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currentPage, int totalRecords){ )?I1*(1{A
everyPage = getEveryPage(everyPage); .nKyB'uV
currentPage = getCurrentPage(currentPage); "4&HxD8_ih
int beginIndex = getBeginIndex(everyPage, =>4>Z_q
G@
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currentPage); l3b$b%0'
int totalPage = getTotalPage(everyPage, z#8GF^U:T
tJ bOn$]2"
totalRecords); CPFd 33
boolean hasNextPage = hasNextPage(currentPage, -O^ b
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totalPage); EX=+TOkAf
boolean hasPrePage = hasPrePage(currentPage); 6=MejT
P[%
W[E<
returnnew Page(hasPrePage, hasNextPage, 86vk"
everyPage, totalPage, Rfeiv
currentPage, fPZBm&`C
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beginIndex); X./8
PK?&
} %7/XZQ
9 qqy( H
privatestaticint getEveryPage(int everyPage){ x44)o:
return everyPage == 0 ? 10 : everyPage; %Kd8ZNv
} S-Ryt>G
vn6/H8
privatestaticint getCurrentPage(int currentPage){ 5i83(>p3]e
return currentPage == 0 ? 1 : currentPage; 2W$c%~j$2
} no)Spo'
r/Qq-1E
privatestaticint getBeginIndex(int everyPage, int Apa)qRJd
:hjeltt
currentPage){ ;)u}`4~L
return(currentPage - 1) * everyPage; mQ('X~l
} It(8s)5
1CFrV=d
privatestaticint getTotalPage(int everyPage, int {KdC51"Nv
4/~8zvz&3
totalRecords){ LV4x9?&
int totalPage = 0; rm1R^n
B`T|M$Ug
if(totalRecords % everyPage == 0) t A\N$
totalPage = totalRecords / everyPage; k2j:s}RHY
else q !EJs:AS
totalPage = totalRecords / everyPage + 1 ; lk2F]@_kJH
FOM~Uj
return totalPage; i ao/l
} aluXh?
WFjNS'WI_
privatestaticboolean hasPrePage(int currentPage){ R^f~aLl
return currentPage == 1 ? false : true; nwOr
} |hiYV
+}I[l,,xy
privatestaticboolean hasNextPage(int currentPage, Yw\}'7
?G*XZ0u~
int totalPage){ I&q:w\\z8|
return currentPage == totalPage || totalPage == *~lD;{2
;]i&AAbj
0 ? false : true; V4l`Alr\L
} [WRs1$5
ryW1OV6?_0
V%<<Udu<
} fP&F$"o8
@zT.&1;`
Ys+Dw-
c<y.Y0
~Rs|W;
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。 9hmCvQgtf
^G~W}z?-
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 % 95:yyH 0
3wX{U8mrg
做法如下: ,B5Ptf#
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ie
2X.#
5w@ ;B
的信息,和一个结果集List: h<Yn0(.
java代码: &oWWc$
Hm-+1Wx
B(:Kw;r?
/*Created on 2005-6-13*/ |n}W^}S5
package com.adt.bo; --Dw
PC.$&x4w1
import java.util.List; awHfd5nRS
)gmDxD
^C
import org.flyware.util.page.Page; fB3O zff
X']>b
/** _-o*3gmbQ
* @author Joa
+h9UV
*/ ^R,5T}J.
publicclass Result { l0U6eOx
h:z;b;
private Page page; -E2[PW4$
J.$<Lnt>u
private List content; 7. G
o!q9pt
/** /JEH%)
* The default constructor (|'w$
*/ xp)#a_}
public Result(){ _-%ay
super(); lE?e1mz{
} Jj fNH
~
T9t9])
/** { )'D<:T
* The constructor using fields d#ya"e>
* 0Y)b319B
* @param page jm.pb/
* @param content .x(&-
*/ C:
kl/9M@
public Result(Page page, List content){ cQ6[o"j.
this.page = page; "*RCV6{
this.content = content; l
YH={jJ
} ]1)@.b;QR
>,@Fz)\:{'
/** D4
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* @return Returns the content.
#7lkj:j4
*/ 3a!/EP
publicList getContent(){ rHT8a^MO
return content; M0=ZAsN
} D'fP2?3FK
g#9w5Q
/** pqMvYF
* @return Returns the page. nI2}E
*/ ^nbze
public Page getPage(){ s.=)p"pTd
return page; Kzo{L
} :{_Or'L
qE$.a[
/** zesEbR)j
* @param content uqTOEHH7
* The content to set. kgr:85
*/ O3bK>9<K
public void setContent(List content){ sn5N9=\+T
this.content = content; Ct }"o
} Xuh_bW&zF
]DmqhK`
/** qgI
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* @param page ;jX_e(T3m
* The page to set. =!#DUfQf
*/ 7w>"M
publicvoid setPage(Page page){ ,yV
pB)IQ
this.page = page; GdG%=+
} |i|YlWQS
} EF"ar
T?AGQcG
.8b4
Cf`UMQ a
\M>AN
Z}
2. 编写业务逻辑接口,并实现它(UserManager, <(BA ws(X
YLSG
5vF+
UserManagerImpl) ei\X/Z*q%P
java代码: Ql&P1|&
<>j,Q
*zX<`E
/*Created on 2005-7-15*/ v|{*y
package com.adt.service; X){F^1CT{
{dMa&r|lp
import net.sf.hibernate.HibernateException; f\r$T Nd6
nJ*NI)
import org.flyware.util.page.Page; /jj!DO#
ni~45WX3
import com.adt.bo.Result; oC4rL\d{
?a}eRA7
/** xZ;';}&pj
* @author Joa 9sYX(Fl
*/ UwE^ij
publicinterface UserManager { 1+y&n?
\F1nEj
public Result listUser(Page page)throws ,ypxy/
}PED#Uv
HibernateException; ^1*p]j(
< "~k8:=4
} Jc:G7}j6
PU-~7h+$
jDXmre?
_ORW'(:Z
^+GN8LUs
java代码: ?7G[`@^Y
p%3';7W\
0HNe44oI+D
/*Created on 2005-7-15*/ fcw\`.
package com.adt.service.impl; A=XM(2{aN
H.>KYiv+
import java.util.List; kQ'G+Kw~F
Ym F`7W
import net.sf.hibernate.HibernateException; Z<&:
W8n
TzK?bbgr!
import org.flyware.util.page.Page; HH+rib'u
import org.flyware.util.page.PageUtil; xPb`CY7
w~Y#[GW
import com.adt.bo.Result; ^'[ |
import com.adt.dao.UserDAO; Q7}wY
import com.adt.exception.ObjectNotFoundException;
VJ=!0v
import com.adt.service.UserManager; \ g0
"4"L"lJ
/** R0/~)
P
* @author Joa ZT^PL3j+
*/ ?C $_?Qi
publicclass UserManagerImpl implements UserManager { J41ZQ
2l\Oufer"
private UserDAO userDAO; S:1! )7
{ld([
/** .S5&MNE
* @param userDAO The userDAO to set. MaMs(
*/ C}00S{nAZ
publicvoid setUserDAO(UserDAO userDAO){ 7XwFO0==
this.userDAO = userDAO; UyF]gO
} Eydk645:3
lcUL7
/* (non-Javadoc) #a .aD+d'
* @see com.adt.service.UserManager#listUser ;c;;cJc!
]]7s9PCN
(org.flyware.util.page.Page) CX1'B0=\r
*/ 'E7|L@X"r
public Result listUser(Page page)throws |20p#]0E+
DAvAozM
HibernateException, ObjectNotFoundException { 9k*'5(D4S
int totalRecords = userDAO.getUserCount(); PMTyiwlm
if(totalRecords == 0) UhEnW8^bz1
throw new ObjectNotFoundException E4{^[=}
W0nRUAo[
("userNotExist"); BRW
page = PageUtil.createPage(page, totalRecords); FijzO
List users = userDAO.getUserByPage(page); XDI@mQmzB
returnnew Result(page, users); SgY>$gP9S
} JgxOxZS`@
IGbQ L
} J7l1-
ZM)a4h,kcm
TI*uNS;-
UnO -?
1$
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 `Y(/G"]
ChBZGuO:
询,接下来编写UserDAO的代码: `GSfA0?
3. UserDAO 和 UserDAOImpl: \y0abxIHS
java代码: U,+=>ns>
CF$^we
y\@XW*_?
/*Created on 2005-7-15*/ 0<P
-` |X
package com.adt.dao; R"82=">v
RQh4RUm
import java.util.List; icnp^2P
$:<KG&Br
import org.flyware.util.page.Page; #=zh&`
U9;AU]A
import net.sf.hibernate.HibernateException; Uq[NOJC
H>W A?4
/** p oNQ<ijK
* @author Joa l$zM|Z1wR`
*/ PVU(RJ
publicinterface UserDAO extends BaseDAO { {j^}"8GB
D&]SPhX
publicList getUserByName(String name)throws hZyz5aZ)K
9cj:'KG)!
HibernateException; \Hy~~Zh2
p~M^' k=d
publicint getUserCount()throws HibernateException; 0mCrA|A.
yTmoEy. q
publicList getUserByPage(Page page)throws yuhSP{pv'
Jj([O2Eq$
HibernateException; u/``*=Y@
hB|LW^@v
} 5$jKw\FF=
&|',o ?'F
^TDHPBlG
JA1(yt
4wK!)Pwq
java代码: WF:i}+g+^
G-T:7
,!Q2^R
/*Created on 2005-7-15*/ CM~)\prks
package com.adt.dao.impl; 0A|.ch
f4:gD*YT
import java.util.List; /tV)8pEj
PCD1I98
import org.flyware.util.page.Page; Pirc49c
4m%_#J{
import net.sf.hibernate.HibernateException; pYVQ-r%QF
import net.sf.hibernate.Query; o,u-%
Q;`#ujxL
import com.adt.dao.UserDAO; CFn!P;.!
7]G3yt->
/** X_"TG;*$
* @author Joa ]3C7guWz
*/ hPH=.rX
public class UserDAOImpl extends BaseDAOHibernateImpl UX(#C,qgG
9r8*'.K`Z
implements UserDAO { Q7f\ 5QjT
gP)g_K(e
/* (non-Javadoc) DmPp&
* @see com.adt.dao.UserDAO#getUserByName 5H>[@_u+:
:3u>%
(java.lang.String) Eiwo==M
*/ #=+d;RdlW
publicList getUserByName(String name)throws XG*Luc-v
6x6PP}IX
HibernateException { `&j5/[>v
String querySentence = "FROM user in class ?!8M
I,c/
r1xNU0A
com.adt.po.User WHERE user.name=:name"; n|3ENN
Query query = getSession().createQuery #(!>
lcyan
(querySentence); @/XA*9]l
query.setParameter("name", name); 91e&-acA
return query.list(); 3fM~R+p
} AEhh
6v
Xb3z<r
/* (non-Javadoc) L)J0TSh
* @see com.adt.dao.UserDAO#getUserCount() E_7N^htv
*/ PJS\> N&u
publicint getUserCount()throws HibernateException { = K}5 fe
int count = 0; _KC()OIeC
String querySentence = "SELECT count(*) FROM B&`#`]
d z&8$(f,
user in class com.adt.po.User"; i5q
VQo
Query query = getSession().createQuery wjQu3 ,Cj
ojUBa/
(querySentence); j:\MrYt0H
count = ((Integer)query.iterate().next i\2~yXw\
GnkNoaU
()).intValue(); "\)j=MI8u+
return count; &8z`]mB{t
} n<uF9N<
4tof[n3us
/* (non-Javadoc) z45ImItH
* @see com.adt.dao.UserDAO#getUserByPage q:+,'&<D
; Sq_DP1W
(org.flyware.util.page.Page) &}Cm9V
*/ (n|PLi
publicList getUserByPage(Page page)throws (%YFcE)SRS
seB ^o}
HibernateException { a9` E&Q}z
String querySentence = "FROM user in class v&D^N9hy9
tc.R(F96
com.adt.po.User"; >7p?^*&7;
Query query = getSession().createQuery u-$(TyDEl|
vzd1:'^t
(querySentence); $&I##od
query.setFirstResult(page.getBeginIndex()) S{zi8Oc6
.setMaxResults(page.getEveryPage()); I_oJx
return query.list(); Cpz'6F^oP
} D({%FQ"
}v"X.fa^
} :na9PW`TC
C%9;~S
"FwbhD0Gb
s(o{SC'tt
7H %>\^A^
至此,一个完整的分页程序完成。前台的只需要调用 # 4L[8(+V
yn)K1f^
userManager.listUser(page)即可得到一个Page对象和结果集对象 L
Me{5H
z}&?^YU*)`
的综合体,而传入的参数page对象则可以由前台传入,如果用 L#1YR}m
wKIQK!B)mF
webwork,甚至可以直接在配置文件中指定。 =c"`>Vi@d
'%vb&a!.6
下面给出一个webwork调用示例: 5IE 2&V
java代码: tXV9+AJ
d<r=f"
!ZJ"lm
/*Created on 2005-6-17*/ [I^>ji0V
package com.adt.action.user; imv[xBA(d
<,$(,RX
import java.util.List; vd6Y'Zk|F6
/GD4GWv :
import org.apache.commons.logging.Log; yZj:Kp+7
import org.apache.commons.logging.LogFactory; =*
oFs|v
import org.flyware.util.page.Page; zxTcjC)y
yl0&|Ub
import com.adt.bo.Result; s`B]+
import com.adt.service.UserService; !`LaX!bmp
import com.opensymphony.xwork.Action; ouL/tt_~
L}T:Y).
/** ^mz&L|h
* @author Joa R @N
I
*/ a{v1[i\
publicclass ListUser implementsAction{ t;!vjac
hy3j8?66
privatestaticfinal Log logger = LogFactory.getLog ;}"_hLX
[p^N].K$
(ListUser.class); yV,ki^^
{4SwCN /
private UserService userService; $6e&sDJ
tpOMKh.`
private Page page; z-$ bce9*
j6]+fo&3
privateList users; +P:xB0Tm
D
G0Q}
1
/* aw&:$twbM
* (non-Javadoc) :8\!; !
* ,K'>s<}
* @see com.opensymphony.xwork.Action#execute() VJmX@zX9
*/ >77N5>]e
publicString execute()throwsException{ Y_tLSOD#/
Result result = userService.listUser(page); veIR)i@dx
page = result.getPage(); %xF
j;U?
users = result.getContent(); /n;Ll](ri
return SUCCESS; :34]}`-
} `?r]OVe{y
S{'/=Px+
/** ErIAS6HS'
* @return Returns the page. U]jHe
*/ `@1y|j:m
public Page getPage(){ lO3W:,3_a
return page; QWz5iM
} a$H*C(wL
=oQw?,eY
/** t\Pn67t
* @return Returns the users. nm5zX,
*/ VO r*YB&
publicList getUsers(){ |U)m'W-(q
return users; G347&F)
} d*Q:[RUf,
k`FCyO
/** G8b/eWtP
* @param page /J!C2
* The page to set. IA_>x9 (~
*/ D#Fe\8!l
publicvoid setPage(Page page){ V;0{o
this.page = page; aV"K%#N
} ^PA[fL"
o>*vG
/** Elth xj
* @param users 9 f$S4O5
* The users to set. 8fA9yQ8
*/ oE@{h$=
publicvoid setUsers(List users){ DY1?37h
this.users = users; v0hr ~1
} 64xq@_+
wgfy; #
/** 2r;^OWwr?
* @param userService 1&N|k;#QS
* The userService to set. :&:IZkO
*/ ;]YQWK
publicvoid setUserService(UserService userService){ F[m"eEX
this.userService = userService; oz
$T.
} juOOD
} 0s )B~
i\hH .7G1
nn><
k"
R-nC+)^
uMOm<kn
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, %SORs(4
7
+A-S9P)
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 )P4#P2
{.F``2
么只需要: D~ _|`D5WK
java代码: `s74g0h
kB_u U !G
]=ar&1}J
<?xml version="1.0"?> gNkx]bm
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork Y^5X>
obWBX'
1.0//EN" "http://www.opensymphony.com/xwork/xwork- dv3+x\`9
[ox!MQ+s
1.0.dtd"> {6MLbL{
/?X1>A:*
<xwork> K|*Cka{
9`{[J['V
<package name="user" extends="webwork- JmN,:bI
w6tb vhcmU
interceptors"> jRIjFn|~{Y
. 2_t/2
<!-- The default interceptor stack name
/;LteBoY
k1;,eB
--> SR>Sq2cW0
<default-interceptor-ref .gUceXWH3
z{T2!w~[
name="myDefaultWebStack"/> UJ'
+Z6d
V+M2Gf
<action name="listUser" bm1+|gssn
cGSoAK
class="com.adt.action.user.ListUser"> + wd} '4)
<param ]:TX> X!
),`MAevp
name="page.everyPage">10</param> bqY}t. Y&"
<result 0[6llcuj
xTQV?g
J
name="success">/user/user_list.jsp</result> ,Ie~zZE&
</action> *8k`m)h26
fM8kS
</package> BcV;EEi
a(CZGIB
</xwork> p'{ `Uvr
$t5
0<1
G3QB Rh{
Q"c!%`\
-eAo3
g;en_~g3j
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 K]dqK'
PZ69aZ*Gs
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 t!^FWr&
3}O.B
r|
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 g3{)AX[Uy
e
#l/jFJU
rN?
L8
bu"Jb4_a>
N]cGJU>$
我写的一个用于分页的类,用了泛型了,hoho Y+N^_2@+C
^5vFF@to
java代码: p-V#nPb
)CS7>Vx
AEkgm^t.{
package com.intokr.util; &*g5kh{
S8j;oJ2d
import java.util.List; u&l2s&i
EK.L>3
/** }]sI?&xB
* 用于分页的类<br> ><iE VrpN
* 可以用于传递查询的结果也可以用于传送查询的参数<br> #I9|>XE1
* DoWY*2E
* @version 0.01 bTC2Ya
* @author cheng xD#PM |I
*/ lD2>`s5
public class Paginator<E> { @Zd+XWFw
privateint count = 0; // 总记录数 }4xxge?r
privateint p = 1; // 页编号 THQW8 V
privateint num = 20; // 每页的记录数 ]OY6.m
privateList<E> results = null; // 结果 yAEOn/.~
g=; rM8W
/** j-$aa;
* 结果总数 HCQv"i}-
*/ 6, ag\
publicint getCount(){ L.(T"`-i
return count; ^8)&~q*
} U0u @[9!
D+rDgrv
publicvoid setCount(int count){ GSV,
this.count = count; t&SJ!>7_c
} d T/*O8
&nn!{S^
/** /6F 1=O(c>
* 本结果所在的页码,从1开始 @FkNT~OZ
* ,IuO;UV#)
* @return Returns the pageNo. YkPz ~;
*/ Y'/` ?CK
publicint getP(){ .^#{rk
return p; 'N=' B<^;%
} eFXxkWR)
`6j?2plZ
/** 3f's>+,#%
* if(p<=0) p=1 /@FB;`'
* ]Ke|wRQD
* @param p k}>l+_*+7
*/ 05*_h0}
publicvoid setP(int p){ 'DsfKR^s
if(p <= 0) &0f7>.y
p = 1; 2bX!-h
this.p = p; y=9a2[3Dz
} <t]c'
EBzg<-?o
/** bXq,iX
* 每页记录数量 2 T{PIJg3
*/ \,
n'D
publicint getNum(){ (#c5Q&