Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 "8MF_Gu):
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 niyV8v
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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 >GRxHK@G
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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
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分页支持类: 0h_|t-9j
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java代码: /x$ nje,.
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package com.javaeye.common.util; 7:1Lol-V
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import java.util.List; Xv^qVn4
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publicclass PaginationSupport { /8S>;5hvK@
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publicfinalstaticint PAGESIZE = 30; |{ip T SH
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privateint pageSize = PAGESIZE; 77Y/!~kd
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privateList items; Gc|idjW4
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privateint totalCount; y6a3tG
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privateint[] indexes = newint[0]; WsB ?C&>x
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privateint startIndex = 0; >[#f\bG>
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public PaginationSupport(List items, int M= (u]%\
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totalCount){ $UwCMPs X
setPageSize(PAGESIZE); ]f_p8?j"
setTotalCount(totalCount); mfr|:i
setItems(items); z{QqY.Gu{G
setStartIndex(0); !a\^Sk
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} 75lA%|
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public PaginationSupport(List items, int g_bLl)g<
]-#DB^EQ
totalCount, int startIndex){ uY To9A
setPageSize(PAGESIZE); W>r+h-kR
setTotalCount(totalCount);
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setItems(items); RA 6w}:sq7
setStartIndex(startIndex); ;xTpE2 -~
} SXh-A1t
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public PaginationSupport(List items, int PKz':_|
p_4<6{KEt
totalCount, int pageSize, int startIndex){ m&3xJuKih
setPageSize(pageSize); ~}
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setTotalCount(totalCount); /;$[E
setItems(items); !ohN!P7&
setStartIndex(startIndex); "AqB$^S9t
} tH4B:Bgj!
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publicList getItems(){ AbM'3Mkz
return items; HoAy_7-5
} 2=}FBA,2
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publicvoid setItems(List items){
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this.items = items; 2\$oV
} BgT*icd8d
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publicint getPageSize(){ dE3) |%
return pageSize; |-H&o]
} \;Weizq5
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publicvoid setPageSize(int pageSize){ 6A ah9
this.pageSize = pageSize; |.dRily+
} |w=zOC;v
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publicint getTotalCount(){ <_+X 88
return totalCount; BA.uw_^4
} XjBD{m(
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publicvoid setTotalCount(int totalCount){ zQ PQ
if(totalCount > 0){ #-J>NWdt
this.totalCount = totalCount; fP1!)po
int count = totalCount / e3\T)x&=
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pageSize; j>kqz>3
if(totalCount % pageSize > 0) y();tsWqc
count++; i
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indexes = newint[count];
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for(int i = 0; i < count; i++){ wd6owr
indexes = pageSize * &^nGtW%a 9
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i; nk:)j:fr
} hbn([+xY
}else{ \M-OC5fQv
this.totalCount = 0; O/LXdz0B
} 2an f$^[
} <VE@DBWyl~
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publicint[] getIndexes(){ :Dp0?&_
return indexes; F'Z,]b'st3
} w-jVC^C]
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publicvoid setIndexes(int[] indexes){
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this.indexes = indexes; 30{ gI0jk
} p
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publicint getStartIndex(){ PvL[e"p
return startIndex; 6u%&<")4HP
} wC*X4 '
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publicvoid setStartIndex(int startIndex){ m {}Lm)M
if(totalCount <= 0) jiGTA:v
this.startIndex = 0; pfPz8L.7
elseif(startIndex >= totalCount) wuBPfb
this.startIndex = indexes !u hT
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[indexes.length - 1]; .)3 <Q}>
elseif(startIndex < 0) TqQ[_RKg2
this.startIndex = 0; ^z\cyT%7t
else{ Nboaf
this.startIndex = indexes OTv)
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[startIndex / pageSize]; {RPI]DcO/
} V[V[~;Py
} {..6>fS
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publicint getNextIndex(){ N>E_%]C h
int nextIndex = getStartIndex() + D+c>F5
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pageSize; A}^mdw9
if(nextIndex >= totalCount) {{1G`;|v9
return getStartIndex(); =MWHJ'3-/
else 3c%caK
return nextIndex; g2]Qv@nxw
} u@444Vzg
]@TCk8d$0
publicint getPreviousIndex(){ ]###w;
int previousIndex = getStartIndex() - wM{s|Ay
{h4E8.E
pageSize; tX[WH\(xI
if(previousIndex < 0) bd`P0f?
return0; 9JwPSAo;
else T4F/w|Q
return previousIndex; SfR%s8c`
} _dU\JD
Xc.`-J~Il
} {G-kNU
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抽象业务类 }a/Cro.~4
java代码: @]0%L0u
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/** k=^xVQuI
* Created on 2005-7-12 (5~h"s
*/ 1x^GWtRp
package com.javaeye.common.business; !m$jk2<
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import java.io.Serializable; V)4J`xg^
import java.util.List; 4K74=r),i
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import org.hibernate.Criteria; x^CS"v7
import org.hibernate.HibernateException; Wl4%GB
import org.hibernate.Session; ?ubro0F:
import org.hibernate.criterion.DetachedCriteria; 5-M-X#(
import org.hibernate.criterion.Projections; AwN!;t_0+N
import ^@]3R QB
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org.springframework.orm.hibernate3.HibernateCallback; \NC3'G:Ii
import Mihg:
,?3G;-
org.springframework.orm.hibernate3.support.HibernateDaoS z{>Rc"%\
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upport; +[P{&\d4}
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import com.javaeye.common.util.PaginationSupport; 0YHFvy)
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public abstract class AbstractManager extends g&.=2uP
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HibernateDaoSupport { e(yh[7p=
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privateboolean cacheQueries = false; @pxcpXCy
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privateString queryCacheRegion; KSL`W2}
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publicvoid setCacheQueries(boolean 8i pez/
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cacheQueries){ =lC7gS!U
this.cacheQueries = cacheQueries; n:X y6H
} 7o4\oRGV
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publicvoid setQueryCacheRegion(String m kexc~l
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queryCacheRegion){ ##{taR8
this.queryCacheRegion = DI%saw
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queryCacheRegion; ctUp=po
} 8_F1AU? u
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publicvoid save(finalObject entity){
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getHibernateTemplate().save(entity); OKV8zO
} 3sk9`=[{$
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publicvoid persist(finalObject entity){ n*$ g]G$
getHibernateTemplate().save(entity); Je{ykL?N
} :pUtSs7p}
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publicvoid update(finalObject entity){ UI#h&j5pW
getHibernateTemplate().update(entity); W4N{S.#!
} F5Va+z,jg
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publicvoid delete(finalObject entity){ Q20%"&Xp]
getHibernateTemplate().delete(entity); he4(hX^
} Y0>y8UV
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publicObject load(finalClass entity, &FD>&WRV
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finalSerializable id){ ]?*wbxU0
return getHibernateTemplate().load 7 3m1
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(entity, id); yjAL\U7`T
} HV.t6@\};
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publicObject get(finalClass entity, #F#%`Rv1
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finalSerializable id){ #S(Hd?34,
return getHibernateTemplate().get v1[29t<I!
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(entity, id); Uv.)?YeGh
} wbHb;]
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publicList findAll(finalClass entity){ +0~YP*I`/
return getHibernateTemplate().find("from d5.4l&\u
pFXEu=$3
" + entity.getName()); Y7aqO5
} 9my^Y9B
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publicList findByNamedQuery(finalString ]3gSQ7
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namedQuery){ 99S^f:t
return getHibernateTemplate dscgj5b1~
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().findByNamedQuery(namedQuery); [~^0gAlQC
} <!+Az,-
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publicList findByNamedQuery(finalString query, .h[:xYm
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finalObject parameter){ "{n&~H`
return getHibernateTemplate ^_6|X]tz1T
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().findByNamedQuery(query, parameter); :svqE+2
} g{Rd=1SK]
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publicList findByNamedQuery(finalString query, ,>M[@4`,U
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finalObject[] parameters){ ~zgGa:uU
return getHibernateTemplate P3%5?.S
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().findByNamedQuery(query, parameters); %;/P&d/
} rUl+
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publicList find(finalString query){ pI[uUu7O
return getHibernateTemplate().find phK/
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(query); XkqCZHYkS
} I*&8^r:A
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publicList find(finalString query, finalObject qLCR] _*
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parameter){ C+]I@Go'Tk
return getHibernateTemplate().find -} +[
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(query, parameter); So;<6~
} .6> w'F{>
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public PaginationSupport findPageByCriteria %C0Dw\A*:
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(final DetachedCriteria detachedCriteria){ L-Lvp%%
return findPageByCriteria >usL*b0%
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ':q p05t
} BWNi [^]
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public PaginationSupport findPageByCriteria .VqhV
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(final DetachedCriteria detachedCriteria, finalint ye97!nIg@
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startIndex){ "|NI]Kv
return findPageByCriteria wq{hF<
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(detachedCriteria, PaginationSupport.PAGESIZE, Q/?$x*\>
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startIndex); Kq!3wb;
} }b}m3i1
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public PaginationSupport findPageByCriteria vX>)je5#
{I((p_
(final DetachedCriteria detachedCriteria, finalint _GPe<H
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pageSize, *i,%,O96Nz
finalint startIndex){ [ )F<V!
return(PaginationSupport) N#]ypl
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getHibernateTemplate().execute(new HibernateCallback(){ 3^ClAE"8
publicObject doInHibernate 7=uj2.J6
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(Session session)throws HibernateException { "tZe>>I
Criteria criteria = e.%nRhSs3
8|^7ai[am
detachedCriteria.getExecutableCriteria(session); m~|40)
int totalCount = h1RSVp+?n
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((Integer) criteria.setProjection(Projections.rowCount xk5]^yDp
_{>vTBU4F
()).uniqueResult()).intValue(); YUb_y^B^
criteria.setProjection RCrCs
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(null); :0/7, i
List items = #4:?gfIj
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criteria.setFirstResult(startIndex).setMaxResults `^vE9nW7
km(Po}
(pageSize).list(); Wqnc{oq|$
PaginationSupport ps = x;S @bY
S/ *E,))m
new PaginationSupport(items, totalCount, pageSize, gUlo]!$
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startIndex); ~o(
return ps; wkq 66?
} .}t
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}, true); ks tIgcI
} ?< />Z)
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public List findAllByCriteria(final l}
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DetachedCriteria detachedCriteria){ K9[UB
return(List) getHibernateTemplate H}!r|nG
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().execute(new HibernateCallback(){ _t$sgz&
publicObject doInHibernate 1\Xw3prH
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(Session session)throws HibernateException { Z;i:](
Criteria criteria = Dv"9qk
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detachedCriteria.getExecutableCriteria(session); ZNoDFf*h
return criteria.list(); 'F<TSy|4kI
} sB</DS
}, true); XSDpRo
} Y73C5.dNcE
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public int getCountByCriteria(final 0f/<7R
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DetachedCriteria detachedCriteria){ pRqx`5 }
Integer count = (Integer) ixFi{_
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getHibernateTemplate().execute(new HibernateCallback(){ D-c4EV
publicObject doInHibernate 2T35{Q!=F
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(Session session)throws HibernateException { . vV|hSc
Criteria criteria = |=w@H]r
f 2.HF@
detachedCriteria.getExecutableCriteria(session); q'DW~!>qX
return BLttb
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criteria.setProjection(Projections.rowCount XUYtEf
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()).uniqueResult(); x4 yR8n(
} pb}*\/s
}, true); \bcLiKE{
return count.intValue(); KwS@D9bok
} tc! #wd+u
} WLT"ji0w2
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用户在web层构造查询条件detachedCriteria,和可选的 [6fQ7uFMM8
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 +rd+0 `}C
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PaginationSupport的实例ps。 yAt^;
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ps.getItems()得到已分页好的结果集 q1,~
ps.getIndexes()得到分页索引的数组 A&VG~r$
ps.getTotalCount()得到总结果数 KPF1cJ2N
ps.getStartIndex()当前分页索引 SU0
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ps.getNextIndex()下一页索引 ! mHO$bQ"
ps.getPreviousIndex()上一页索引 fVlB=8DNk&
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 p+eh%2Jm
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做
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一下代码重构了。 F%|h;+5
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我把原本我的做法也提供出来供大家讨论吧: qm}@!z^
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首先,为了实现分页查询,我封装了一个Page类: ^!d3=}:0
java代码: iTwm3V
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/*Created on 2005-4-14*/ d=(mw_-?
package org.flyware.util.page; LoV<:|GTI
jp,4h4C^)
/** K0~rN.C!0
* @author Joa ?4 ,T}@P
* 1?}T=)3+$
*/ DQ3<$0
publicclass Page { dN q$}
h{Y",7]!
/** imply if the page has previous page */ N7"W{"3D
privateboolean hasPrePage; h`q1
s;e\ pt
/** imply if the page has next page */ 3`g^
privateboolean hasNextPage; b}`TLn
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/** the number of every page */ <I?Zk80
privateint everyPage; 7.Op<
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/** the total page number */ X'srL j.
privateint totalPage; dV_G1'
]^E?;1$f?
/** the number of current page */ la!~\wpa
privateint currentPage; :TbgFQ86~
}vuO$j
/** the begin index of the records by the current CJY$G}rk
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query */ Ui~>SN>s
privateint beginIndex; 1}x%%RD_
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/** The default constructor */ +(Ae4{z"1+
public Page(){ /v{I
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} 4(+PD&_J
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/** construct the page by everyPage Et$2Y-L.
* @param everyPage ^8WRqQdx
* */ t.<i:#rj>l
public Page(int everyPage){ |Cv!,]9:r
this.everyPage = everyPage; (.:e,l{U%
} ah "o~Cbj
/^ts9:
/** The whole constructor */ >MZ/|`[M
public Page(boolean hasPrePage, boolean hasNextPage, r!v\"6:OM
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int everyPage, int totalPage, #qki
int currentPage, int beginIndex){ y29m/i:
this.hasPrePage = hasPrePage; IGl9g_18
this.hasNextPage = hasNextPage; M`_0C38
this.everyPage = everyPage; HMXE$d=[
this.totalPage = totalPage; O.? JmE
this.currentPage = currentPage; _BufO7`.
this.beginIndex = beginIndex; )~>YH*g
} %9"H
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/** cAw/I@jG
* @return UQsN'r\tS
* Returns the beginIndex. M\j.8jG
*/ W/N7vAx X
publicint getBeginIndex(){ U{mYTN*:j$
return beginIndex; Qs!5<)6
} ".%k6W<n
>P(.:_^p
/** mpyt5#f
* @param beginIndex :FF=a3/"6
* The beginIndex to set. gXU8hTd8
*/ JF]JOI6.e
publicvoid setBeginIndex(int beginIndex){ 4+n\k
this.beginIndex = beginIndex; @ Qe0! (_=
} 7zMr:JmV
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/** }V>T M{
* @return crCJrN=
* Returns the currentPage. z?zL9 7H
*/ @EAbF>>
publicint getCurrentPage(){ =4!mAo}
return currentPage; 3`HV(5U[
} xw%0>K[
x-c"%Z|
/** jIyQ]:* p
* @param currentPage fA-7VdR`R
* The currentPage to set. G}*hM$F
*/ ?2a $*(
publicvoid setCurrentPage(int currentPage){ GbyJ:
this.currentPage = currentPage; X&zis1A<
} 1M-pr 8:6s
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/** E7hhew
* @return zDp 2g)
* Returns the everyPage. a.'*G6~Qgw
*/ ^.tg 7%dJ
publicint getEveryPage(){ b6[j%(
return everyPage; qR.Q,(b|
} 9L9sqZUB
TC. ,V_
/** (hsl~Jf
* @param everyPage )"LJ
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* The everyPage to set. m|# y
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*/ NI5``BwpO
publicvoid setEveryPage(int everyPage){ n%-0V>
this.everyPage = everyPage; E]6
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} Bx!-"e
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/** tkhCw/
* @return !wNO8;(
* Returns the hasNextPage. l2d{ 73h
*/ ToQ"Iy?
publicboolean getHasNextPage(){ u-TUuP
return hasNextPage; wzaV;ac4K
} ,Q,^3*HX9}
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/** hph4 `{T
* @param hasNextPage h![#;>(
* The hasNextPage to set. f?b"i A(6
*/ ,[Fb[#Qqb
publicvoid setHasNextPage(boolean hasNextPage){ l,:F
this.hasNextPage = hasNextPage; Q&&@v4L
} JRFtsio*
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/** /=h` L,
* @return zQA`/&=Y
* Returns the hasPrePage. H"KCK6
*/ ;=@0'xPEa-
publicboolean getHasPrePage(){ -8Xf0_
return hasPrePage; +#By*;BJ
} vy/-wP|1
]9XDS[<2`
/** +RXoi2"-q@
* @param hasPrePage Wm|lSisY
* The hasPrePage to set. eFAnFJ][L
*/ R3!t$5HG
publicvoid setHasPrePage(boolean hasPrePage){ jal-9NV)!
this.hasPrePage = hasPrePage; 9kojLqCT
} 7KPwQ?SjT
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/** F"<vaqT2
* @return Returns the totalPage. ccnK#fn v
* [Yyk0Qv|4
*/ l@\FWWQ
publicint getTotalPage(){ Tr|JYLwF
return totalPage; *kVV+H<X|b
} b\ PgVBf9
@KA4N`
/** V:27)]q
* @param totalPage ]~%6JJN7
* The totalPage to set. jtc~DL
*/ K>9 ()XT)
publicvoid setTotalPage(int totalPage){ PX99uWx5]
this.totalPage = totalPage; qNr}
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} {U1m.30n
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} Q^I\cAIB
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U3kyraj
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 7rPF$ \#
8] ikygt"
个PageUtil,负责对Page对象进行构造: J=L5=G7(
java代码: ?}7p"3j'z
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66 Tpi![
/*Created on 2005-4-14*/ 7?t6UPf
package org.flyware.util.page; ^J d
r>@
v@Ox:wl>
import org.apache.commons.logging.Log; V$~9]*Wn
import org.apache.commons.logging.LogFactory; 3~\[7I/
d\Zng!Z '
/** vI]N^j2%
* @author Joa _~pbqa,
* 5PW^j\G-f
*/ rGkyGz8>
publicclass PageUtil { c)tfAD(N8x
\Roz$t-R|f
privatestaticfinal Log logger = LogFactory.getLog x`?3C"N:<
4fzZ;2sl}
(PageUtil.class); akT6^cP^
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/** !by\9
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* Use the origin page to create a new page kW (Bkuc)
* @param page j7c3(*Pl
* @param totalRecords H|D.6^
* @return +"6`q;p3)
*/ l(q ,<[O
publicstatic Page createPage(Page page, int ty`DJO=Omj
CP{cAzHO
totalRecords){ @I*{f
return createPage(page.getEveryPage(), |CzSU1ma
]_f<kW\1*
page.getCurrentPage(), totalRecords); '\GbmD^F
} v}x&?fU `
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/** V>
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* the basic page utils not including exception j5ve2LiFV%
EIQ
p>|5
handler -(#iIgmP
* @param everyPage Q&V;(L62!
* @param currentPage E!#WnSpnK
* @param totalRecords _y>~
yZx
* @return page /=, nGk>
*/ "vslZ`RU
publicstatic Page createPage(int everyPage, int Q|L~=9
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currentPage, int totalRecords){ B]$GSEB
everyPage = getEveryPage(everyPage); <|\Lm20G]
currentPage = getCurrentPage(currentPage); +]50D xflA
int beginIndex = getBeginIndex(everyPage, Yuc> fFA
c=+!>Z&i$G
currentPage); )0R'(#
int totalPage = getTotalPage(everyPage, )Beiu*
X|8c>_}
totalRecords); m9A!D
boolean hasNextPage = hasNextPage(currentPage, Bw{I;rW{2
-GgA&dh
totalPage); YDFyX){
boolean hasPrePage = hasPrePage(currentPage); (khL-F
F:l%O#V
returnnew Page(hasPrePage, hasNextPage, 5^KWCS7@
everyPage, totalPage, BCcjK6'
currentPage, h=%_Ao<x
7`YEH2
beginIndex); lPJ\-/>$z
} l$'wD hN*
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privatestaticint getEveryPage(int everyPage){ V/;B3t~f
return everyPage == 0 ? 10 : everyPage; .%OR3"9@
} -R6)ROGl
TuYCR>P[
privatestaticint getCurrentPage(int currentPage){ #!m.!?
O
return currentPage == 0 ? 1 : currentPage; (3&?w y_l
} -)/$M(Pu"
h65-s
privatestaticint getBeginIndex(int everyPage, int -Vhw^T1iV
&=k,?TJO>
currentPage){ =kqt
return(currentPage - 1) * everyPage; fg{n(TE"8
} X~i<g?]
hiw|2Y&`
privatestaticint getTotalPage(int everyPage, int pO.2<
8h4'(yGQQW
totalRecords){ uXq.
]ub
int totalPage = 0; gl_^V&c
TNr :pE<
if(totalRecords % everyPage == 0) BV+ Bk+
totalPage = totalRecords / everyPage; S/I /-Bp~
else Jdp3nzM^^@
totalPage = totalRecords / everyPage + 1 ; :Xd<74Nu
.y,0[i V
N
return totalPage; ~| 6[j<ziL
} K}U-w:{
WSY}d
Vr
privatestaticboolean hasPrePage(int currentPage){ PAOJ\U
return currentPage == 1 ? false : true;
EUgs6[w 4
} zZC9\V}R
V,?yPi$#E
privatestaticboolean hasNextPage(int currentPage, -FlzEZ
"2T#MO/
int totalPage){ /Qk4
return currentPage == totalPage || totalPage == kn"(A.R
mo#04;VF
0 ? false : true; bD8Gwi=iiu
} P_#bow
(NnH:J`
t>B;w14
} <kd1Nrr!p
SG4%}wn%
BIWWMg
[\b0Lem
8&Y^""#e)
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 M+9 gL3W
#`X?=/q
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 ApXy=?fc
f8.gT49I
做法如下: G<^{&E+=
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 MO <3"@/,
NS6:yX,/
的信息,和一个结果集List: mcX/GO}
java代码: 9lDhIqx0~
=+?7''{>
9v!1V,`j"
/*Created on 2005-6-13*/ !GEJIefx_
package com.adt.bo; e,XYVWY%
w~?~g<q
import java.util.List; xLZG:^(I
?_"ik[w}
import org.flyware.util.page.Page; t\j*}# S
E'.7xDN
/** 3CGp`~Zf
* @author Joa k/gZ,
*/ Q7COQ2~K
publicclass Result { v+=BCyT
x*&|0n.D
private Page page; 84 pFc;<
-n<pPau2
private List content; Y~E`9
3%;a)c;D
/** ([LSsZ]sj
* The default constructor 4u47D$=
*/ ["e3Ez
public Result(){ U\<?z Dw
super(); 7y@Pa&^8
} WYYa/,{9.
)$bS}.
/** do+.aOC
* The constructor using fields kO*$"w#X[p
* n%s]30Xs
* @param page "?I y (*^
* @param content
2WVka
*/ (<oyN7NT
public Result(Page page, List content){ ?r 2` Q
this.page = page; LRG6:&
this.content = content; &wE%<"aRAl
} o\pVp bB
TNh1hhJ$b
/** #PQB(=299P
* @return Returns the content. BC<^a )D=
*/ K8.!_
c
publicList getContent(){ :#?5X|Gz
return content; f|lU6EkU
} J9iy
o/Q;f@
/** !pdb'*,n
* @return Returns the page. K]"#C
*/ [ )dXI IM
public Page getPage(){ JU5C}%Q6
return page; b4ONh%
} A_5P/ARmI
0h\smqm
/** -Z
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* @param content CxG#"{&
* The content to set. vucxt }Ti
*/ Om@C
X<(9C
public void setContent(List content){ :GP]P^M;G@
this.content = content; ApV~(k)W
} ~C`^6UQr/?
4'A!; ]:
/** z] ?N+NHOA
* @param page l6 H|PR{
* The page to set. \(Y\|zC'0$
*/ e`xdSi>E
publicvoid setPage(Page page){ B%76rEpvW;
this.page = page; D(RTVef
} ^y1j.M@q
} (/j/>9iro
O7<]U_"I
.1Al<OLL
[t@Mn
wlk4*4dKn
2. 编写业务逻辑接口,并实现它(UserManager, L(-b@Joh
_JE"{ ;
UserManagerImpl) b@f$nS
B
java代码: E:}r5S)4
k $J zH$
[knN:{ l
/*Created on 2005-7-15*/ 4$S;(
package com.adt.service; /%TI??PGu
'JfdV%M
import net.sf.hibernate.HibernateException; lP@Ki5
<Fc;_GG
import org.flyware.util.page.Page; (ECnMti+
^xh ;
import com.adt.bo.Result; LNpup`>`
#32"=MfQn
/** % <*g!y `
* @author Joa HbAkZP
*/ 0ANZAX5
publicinterface UserManager { kZZh"#W: L
cm[&?
public Result listUser(Page page)throws z>Hgkp8D"
$gy*D7
HibernateException; X4E%2-m@'
a8iQ4
} =&2Lb
^,_w$H
`A^"%@j
C:C}5<fkx
DB:+E|vSD
java代码: /.M N
!0@Yplj
_Khc3Jo
/*Created on 2005-7-15*/ Z99>5\k
package com.adt.service.impl; TbGn46!:
Dg?70v<a
import java.util.List; JB`\G=PiL
.my0|4CQ#@
import net.sf.hibernate.HibernateException; _:C9{aEZb
DhT>']Z
import org.flyware.util.page.Page; v` 7RCg`
import org.flyware.util.page.PageUtil; ie\"$i.98H
PCM-i{6/
import com.adt.bo.Result; Ry K\uv
import com.adt.dao.UserDAO; -~ Mb
import com.adt.exception.ObjectNotFoundException; 5Z\#0":e
import com.adt.service.UserManager; ws|;`
#9xd[A: N
/** m{uxIza
* @author Joa )3w@]5j
*/ % !>I*H
publicclass UserManagerImpl implements UserManager { g,95T Bc
MLWM&cFG
private UserDAO userDAO; ;\Y&ce
T}P".kpbS
/** !Kj,9NX{U
* @param userDAO The userDAO to set. @I/]D6
~"
*/ "zRoU$X
publicvoid setUserDAO(UserDAO userDAO){ kg3EY<4i
this.userDAO = userDAO; ); dT_
} b e-~\ @
jvFTR'R)=
/* (non-Javadoc) M:3h e
* @see com.adt.service.UserManager#listUser }36QsH8
;u(<h?%e
(org.flyware.util.page.Page) ;)e2@'Agl
*/ D-(w_$#
public Result listUser(Page page)throws 3G~@H>j
Z1Z1@2 T
HibernateException, ObjectNotFoundException { (%xwl
int totalRecords = userDAO.getUserCount();
Mo @C9Y0
if(totalRecords == 0) JJ'.((
throw new ObjectNotFoundException *B{j.{
p(
[E
JQ>?D
("userNotExist"); Jesjtcy<*
page = PageUtil.createPage(page, totalRecords); [YT>*BH ?
List users = userDAO.getUserByPage(page); c 8>hcV
returnnew Result(page, users); S9`flo
} uVDa^+=
mB9r3[
} }S$@ Ez6
UE ,t8j
x{c/$+Z[
<l9-;2L4
!\L/[:n
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 `Ru3L#@
nMvKTH
询,接下来编写UserDAO的代码: {0^&SI"5`E
3. UserDAO 和 UserDAOImpl: GF%314Xu
java代码: I{:(z3
.j>hI="b
/&{$ pM|?
/*Created on 2005-7-15*/ )!:Lzi
package com.adt.dao; lBFMwJU)
GJp85B!PlO
import java.util.List; qfz 8jY]
xD[Gq%
import org.flyware.util.page.Page; /iV}HV0
<xC#@OZ
import net.sf.hibernate.HibernateException; z;wELz1L{
e=;AfK
/** %v7[[U{T
* @author Joa /2Bi@syxK
*/ ?6jkI2w
publicinterface UserDAO extends BaseDAO { K/=_b<
:`2=@ .
publicList getUserByName(String name)throws X>.
NFB
*@)O7vB
HibernateException; R@#G>4
z,bQQ;z9
publicint getUserCount()throws HibernateException; w MP
' dx1x6
publicList getUserByPage(Page page)throws nn9wdt@.]
O
Wj@<N
HibernateException; k{$ ao
(%o2jroQ#
} z2hc.29t
\$OF1i@
@b~fIW_3>
9Q-*@6G
(N=5.7"T
java代码: { e5/+W
"0k8IVwp
g{9+O7q
/*Created on 2005-7-15*/ -,{-bi
package com.adt.dao.impl; ]B]*/
]$\|ktY!
import java.util.List; j$Je6zq0x
,SiY;(b=\
import org.flyware.util.page.Page; pOkLb
#
JiU9CeD3
import net.sf.hibernate.HibernateException; ?8mlZ
X9C
import net.sf.hibernate.Query; U}l14
zf>5,k'x'A
import com.adt.dao.UserDAO; FwZ>{~?3
~/ilx#d
/** ^F"iP7
* @author Joa @*DyZB
*/ dk<XzO~g
public class UserDAOImpl extends BaseDAOHibernateImpl NwR}yb6
Z@%HvB7
implements UserDAO { 9bq<GC'eX8
gOK\%&S]
/* (non-Javadoc) [e4]"v`N
* @see com.adt.dao.UserDAO#getUserByName ?
j
9|5*
~w;]c_{.b
(java.lang.String) d4 (/m_HMu
*/ ~E^,=4
publicList getUserByName(String name)throws U"4?9.
k
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HibernateException { ~|AwN [
String querySentence = "FROM user in class r]Ff{la5
@hImk`&[N
com.adt.po.User WHERE user.name=:name"; #vqo -y7@
Query query = getSession().createQuery z|(+|pV(
ii0Ce}8d~
(querySentence); wB{;bB{
query.setParameter("name", name); /Y2/!mU</
return query.list(); F[!ckes<bB
} `H3.,]
`3'0I /d"z
/* (non-Javadoc) ~b|`'kU
* @see com.adt.dao.UserDAO#getUserCount() 1I}b|6
`
*/ $CE[MZ&S
publicint getUserCount()throws HibernateException { +EM_TTf4
int count = 0; &h,5:u
String querySentence = "SELECT count(*) FROM ,*@AX>
NCf"tK'5n
user in class com.adt.po.User"; ,xT?mt}P
Query query = getSession().createQuery e%>b+Sv
A[YpcG'9
(querySentence); l@hjP1o
count = ((Integer)query.iterate().next m G1IQ!
=0'q!}._!
()).intValue(); ]k8/#@19
return count; irZFV
} Kw`VrcwjT
eb8w~
/* (non-Javadoc) s$*'^:
* @see com.adt.dao.UserDAO#getUserByPage
l"zUv
/)rkiwp
(org.flyware.util.page.Page) WWZ9._
*/ VNtPKtx\
publicList getUserByPage(Page page)throws ,[nm_^R*\
6R29$D|HFO
HibernateException { ='E$-_
String querySentence = "FROM user in class oQj=;[
Ij'NC C
com.adt.po.User"; 47T}0q,
Query query = getSession().createQuery ^-M^gYBR
._96*r=o
(querySentence); a/uo}[Y
query.setFirstResult(page.getBeginIndex()) ag4`n:1
.setMaxResults(page.getEveryPage()); "XLe3n
return query.list(); OlQ,Ce
} S|GWcSg
'?yCq$&
} Ab1/.~^
FCc=e{
-6Mm#sX
B )JM%r
O;]?gj 1@
至此,一个完整的分页程序完成。前台的只需要调用 Sb:T*N0gS
vG2b:[W
userManager.listUser(page)即可得到一个Page对象和结果集对象 <39!G7ny
lKEa)KF[
的综合体,而传入的参数page对象则可以由前台传入,如果用 Y#01o&f0n
8 )\M:s~7&
webwork,甚至可以直接在配置文件中指定。 qOG}[%<^n7
2PSTGG8JV
下面给出一个webwork调用示例: 7>
Pgc
java代码: p&K\]l}
~mN%(w!^
%E27.$E_
/*Created on 2005-6-17*/ ~-F?Mc
package com.adt.action.user; 6bZ[Kt
#rYENR[
import java.util.List; u; TvS
|
^`qPs/b
import org.apache.commons.logging.Log; em]xtya
import org.apache.commons.logging.LogFactory; &4$oudn
import org.flyware.util.page.Page; WO,xMfK
[ev-^[
import com.adt.bo.Result; (w2=
2$
import com.adt.service.UserService; '?Iif#Z1
import com.opensymphony.xwork.Action; <V_7|)'/A
>AI<60/<
/** *N/hc
* @author Joa ,dd WBwMK
*/ aN^IP
publicclass ListUser implementsAction{ hGP1(pH.
Vul+]h[!h
privatestaticfinal Log logger = LogFactory.getLog q3'o|pp
fV ZW[9[
(ListUser.class); |Zq\GA
xNN@ 1P[*
private UserService userService; hWcTI{v
i.rU&yT%
private Page page; xT F=Y_
04y!\
privateList users; CM~MoV[k7e
LI:Tc7t
/* ur2!#bU9
* (non-Javadoc) xKJ>gr"w#
* @5}gsC
* @see com.opensymphony.xwork.Action#execute() S@:B6](D$
*/ U 0ZB^`
publicString execute()throwsException{ :LV.G0)#
Result result = userService.listUser(page); <Ns &b.\h6
page = result.getPage(); :J(sXKr[C
users = result.getContent(); @PcCiGZ
return SUCCESS; nJVp.*S
} {(vOt '
,{j4
/** +*t|yKO>[
* @return Returns the page. TV{)n'aA
*/ Z|`fHO3j
public Page getPage(){ =%h~/,
return page; A'"-m)1P
} L=7rDW)aa
i@$-0%,
/** %N~;{!![p
* @return Returns the users. "oE* 9J?e
*/ K~>jApZ%
publicList getUsers(){ ~5t?C<wo
return users; xtJAMo>g
} _IYY08&(r
t>U!Zal"
/** {of]/3=
* @param page pVOI5>f\
* The page to set. ?*K<*wBw#
*/ ,ZK]i CGk
publicvoid setPage(Page page){ b]`^KTYK
this.page = page; iUNnPJh
} 5a$$95oL
#O</\|aH)i
/** !s-/0ugZ
* @param users w<d*#$[,*
* The users to set. &`PbO
*/ piu0^vEEH
publicvoid setUsers(List users){ 8!j=vCv
this.users = users; uJPH~mdW
} b|E/LKa
uiK:*[
/** !Y%D
9
* @param userService >0T3'/k<H
* The userService to set. #^\}xn"[
*/ $j
!8?
publicvoid setUserService(UserService userService){ nO@+s
F
this.userService = userService; kukaim>K
} d8.ajeN]o
} +{xG<Wkltz
FT_k^CC
b]dxlj}
<
s,
-*q}
EVSK8T,
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, 3o7xN=N
B&nw#saz.
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 0Uaem
J3\)Jy
么只需要: GI4oQcJ
java代码: &enlAV'#)O
s=\7)n=,M
em/Xu
<?xml version="1.0"?> 2B'^`>+8S
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork *dVD
F`D9Zfd
1.0//EN" "http://www.opensymphony.com/xwork/xwork- Nz @8
di<B ~:l58
1.0.dtd"> sWW\bK0B4
y7;
5xF?q
<xwork> Heohe|an
t;XS;b%
<package name="user" extends="webwork- g)N54WV
(lb`#TTGx
interceptors"> .9I_NG
r1hD
%a
<!-- The default interceptor stack name ZE ^u .>5
dAwS<5!
--> wL'C1Vr
<default-interceptor-ref q"p#H 8
!pV<n
name="myDefaultWebStack"/> K*[0dza$
9T]va]w?#
<action name="listUser" C[W5d~@;E
KPg[-d
class="com.adt.action.user.ListUser"> \
>(zunL
<param FP@A;/c
UR\ZN@O
name="page.everyPage">10</param> }9FD/
<result o5V`'[c
x/[8Wi,yB
name="success">/user/user_list.jsp</result> K5+!(5V~
</action> %)dI2 J^Xf
:3 PG f
</package> 7ozYq_ $
TwwIt5_fN
</xwork> 1+FYjh!2t
@ p"NJx"
hF9B?@n?B
U!_sh<
7~lB}$L
NB3/A"}"02
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 `lvh\[3^
yvS^2+jW
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。 &(WE]ziuO
uq]iMz>
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 4=UI3 2v3
w8U2y/:>
<xC:Ant
-D$3!ccX
F1/6&u9I
我写的一个用于分页的类,用了泛型了,hoho 4g S[D
7!mJhgGc
java代码: 9c:5t'Qt5.
Age-AJ
- =yTAx
package com.intokr.util; wiKCr/
\v.HG]
/u
import java.util.List; _82<|NN:
D@2Ya/c
/** ^CO#QnB @
* 用于分页的类<br> kaV%0Of]
* 可以用于传递查询的结果也可以用于传送查询的参数<br> mMga"I9
* MyK^i2eD
* @version 0.01 -Zttj /K
* @author cheng G|<] Ma9x
*/ |F3vRt@
public class Paginator<E> { EmYO5Whi
privateint count = 0; // 总记录数 _dz+2au
privateint p = 1; // 页编号 2c!h2$w
privateint num = 20; // 每页的记录数 f*UBigk
privateList<E> results = null; // 结果 S_`W@cp[
'o7R/`4KR
/** 9F/|`
* 结果总数 1g+LF[*-~
*/ (tgEa{rPAP
publicint getCount(){ WvIK=fdZ$
return count; x0y%\
} cvn-*Sj
(}VuiNY<