Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 4ZYywD wn
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 i@%a!].I
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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 Vp1Nk#H
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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 {Wr5F9q
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分页支持类: @Q!Tvw/
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java代码: f/m0,EERk
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package com.javaeye.common.util; P#rS.CIh
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import java.util.List; _~2o
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publicclass PaginationSupport { SI=7$8T5=5
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publicfinalstaticint PAGESIZE = 30; ITz+O=I4R]
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privateint pageSize = PAGESIZE; >3I|5kZ6
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privateList items; 1>umf~%Wa
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privateint totalCount; vSCJ xSt#e
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privateint[] indexes = newint[0]; m;U_oxb
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privateint startIndex = 0; w,0OO
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public PaginationSupport(List items, int hdH3Jb_hl(
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totalCount){ B& 5Md.h
setPageSize(PAGESIZE); =t.T9'{
setTotalCount(totalCount); Xs~IoU
setItems(items); }yd!UU
setStartIndex(0); 74c5\UxA
} xE*.,:,&
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public PaginationSupport(List items, int &WS'Me
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totalCount, int startIndex){ Q+O./1x*,
setPageSize(PAGESIZE);
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setTotalCount(totalCount); ^bLFY9hSC
setItems(items); o76{;Bl\O
setStartIndex(startIndex); x((Rm_'
} .
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public PaginationSupport(List items, int Fnd_\`9{
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totalCount, int pageSize, int startIndex){ z]&?}o
setPageSize(pageSize); [7,q@>:CS
setTotalCount(totalCount); _auFt"n
setItems(items); HzsQ`M4cA
setStartIndex(startIndex); gIKQip<
} 7s Gf_`Z
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publicList getItems(){ c/l^;6O/!\
return items; \4O_@d`A
} C>QWV[F
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publicvoid setItems(List items){ z00,Vr^m
this.items = items; {=;<1PykLb
} 4v9d&
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publicint getPageSize(){ :*YnH&
return pageSize; {W=5
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} )G*xI`(@
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publicvoid setPageSize(int pageSize){ ~"8r=8|
this.pageSize = pageSize; VL|Z+3L
} hUEA)c
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publicint getTotalCount(){ wR"17z7[]
return totalCount; F!-%v5.y
} HumL(S'm
7"OJ,Mx%
publicvoid setTotalCount(int totalCount){ FbXur- et^
if(totalCount > 0){ %8xK BL]J
this.totalCount = totalCount; dk 0} q6~
int count = totalCount / Tl1H2s=G-
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pageSize; >Sb3]$$
if(totalCount % pageSize > 0) s@6Jz\<E
count++; "/%o'Fq
indexes = newint[count]; $weC '-n@
for(int i = 0; i < count; i++){ x0lAJaG
indexes = pageSize * pnXwE-c_
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i; p =-~qBw
} (k_9<Yb3
}else{ kM(m$Oo.
this.totalCount = 0; )4>7X)j>
} ARG8\qU
} t/l<X]o
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publicint[] getIndexes(){ Kq(JHB+
return indexes; g8@F/$HY
} Lyit`j~yH
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publicvoid setIndexes(int[] indexes){ JEF ;Q
this.indexes = indexes; d\25
} #7KR`H
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publicint getStartIndex(){ D
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return startIndex; /QQjb4S}
}
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publicvoid setStartIndex(int startIndex){ ,5AEtoF
if(totalCount <= 0) -aV(6i*n
this.startIndex = 0; Zay%QNsb
elseif(startIndex >= totalCount) EK&0Cn3z
this.startIndex = indexes 0E)M6
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[indexes.length - 1]; ,H1K sN
elseif(startIndex < 0) }F|B'[wn
this.startIndex = 0; hE<Sm*HU
else{ }daU/
this.startIndex = indexes Wfy+9"-;s
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[startIndex / pageSize]; KLG29G
} @uanej0q7
} |*Oi:)qt
}Yc5U,A;
publicint getNextIndex(){ P'DcNMdw
int nextIndex = getStartIndex() + DO( 3hIj
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pageSize; !Uv>>MCr
if(nextIndex >= totalCount) /y6I I$AvM
return getStartIndex(); f.$*9Fkw
else ZB}A^X
return nextIndex; ;lfv.-u:<
} 1U?5/Ja
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publicint getPreviousIndex(){ v["_t/_
int previousIndex = getStartIndex() - uBxoMxWm
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pageSize; &gUa^5'#
if(previousIndex < 0) 6Nt/>[
return0; >(.Y%$9"E
else 7|GSs=
return previousIndex; 1N<n)>X4
} z4;@"B
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} A;dD'Kgl
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抽象业务类 tU *`X(;
java代码: b=U3&CV9
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/** zx*D)i5-
* Created on 2005-7-12 y,bDi9*|
*/ vVrM[0*c
package com.javaeye.common.business; {m@tt{%
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import java.io.Serializable; _pDfPLlY&
import java.util.List; dCo3 VF"u
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import org.hibernate.Criteria; Eggu-i(rD
import org.hibernate.HibernateException; xA`j:zn'j
import org.hibernate.Session; uGm?e]7Hx<
import org.hibernate.criterion.DetachedCriteria; =;E0PB_w
import org.hibernate.criterion.Projections; 9!kp3x/`
import M'F<1(
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org.springframework.orm.hibernate3.HibernateCallback; [J(b"c6
import YD0hDp
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org.springframework.orm.hibernate3.support.HibernateDaoS ) xKW
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upport; E31YkD.A
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import com.javaeye.common.util.PaginationSupport; O.-n&U9
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public abstract class AbstractManager extends WuFBt=%
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HibernateDaoSupport { =LKM)d=1
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privateboolean cacheQueries = false; Yl:[b{Py
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privateString queryCacheRegion; ;r&Z?B$
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publicvoid setCacheQueries(boolean M_>kefr
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cacheQueries){ /oLY\>pD
this.cacheQueries = cacheQueries; MLg{Y?@
} _[-W*,xJ)
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publicvoid setQueryCacheRegion(String O&yAFiCd
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queryCacheRegion){ ]61HQ
this.queryCacheRegion = T,rRE7
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queryCacheRegion; 6,MQT,F
} dv+ZxP%g
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publicvoid save(finalObject entity){ *?]<=IV?
getHibernateTemplate().save(entity); c b&Yf1
} /&_q"y9
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publicvoid persist(finalObject entity){ {@3v$W~7M
getHibernateTemplate().save(entity); 8lGM>(:o
} h/5S2EB0!O
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publicvoid update(finalObject entity){ HtiIg a 7
getHibernateTemplate().update(entity); KfYU.Q
} CV_M |
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publicvoid delete(finalObject entity){ W$()W)
getHibernateTemplate().delete(entity); `wQs$!a
} }f14# y;
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publicObject load(finalClass entity, G6}&k[d5%
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finalSerializable id){ 4>LaA7)v
return getHibernateTemplate().load *|<~IQg
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(entity, id); LHXR7Fjc
} &5${k'
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publicObject get(finalClass entity, Yf~Kzv1]*
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finalSerializable id){ 1 ]
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return getHibernateTemplate().get 0I<L<^s3^U
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(entity, id); FfrC/"N
} #D|%r-:"
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publicList findAll(finalClass entity){ ViMl{3
return getHibernateTemplate().find("from aq8./^
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" + entity.getName()); D,[Nn_N
} ]'M B3@T
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publicList findByNamedQuery(finalString ZfH>UHft
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namedQuery){ nqo1+OR
return getHibernateTemplate UZrEFpi
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().findByNamedQuery(namedQuery); #+V4<o
} cL~WDW/
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publicList findByNamedQuery(finalString query, T*PEUq
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finalObject parameter){ kWVk^,
return getHibernateTemplate iLNUydiS
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().findByNamedQuery(query, parameter); b1jDbiH&
} 4%w<Ekd
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publicList findByNamedQuery(finalString query, 6$=>ck P
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finalObject[] parameters){ m"'LT0nur
return getHibernateTemplate + xO3<u
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().findByNamedQuery(query, parameters); =b>TF B=*N
} qHdUnW
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publicList find(finalString query){ EPH" 5$8
return getHibernateTemplate().find <!XunXh
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(query); Skg/iH"(
} D&2NO/
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publicList find(finalString query, finalObject &]RE 5!
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parameter){ Z|Rc54Ct
return getHibernateTemplate().find @KU;'th
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(query, parameter); *pSnEWwE
} &*ocr &
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public PaginationSupport findPageByCriteria -Yh(bS
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(final DetachedCriteria detachedCriteria){ )UF'y{K}
return findPageByCriteria 8h@L_*Kr
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Qkx*T9W
} %_4#WI
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public PaginationSupport findPageByCriteria : slO0
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(final DetachedCriteria detachedCriteria, finalint y&5
O)
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startIndex){ SJa>!]U'xI
return findPageByCriteria P-gj SE|yh
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(detachedCriteria, PaginationSupport.PAGESIZE, qve'Gm)
La9}JvQoX
startIndex); u*P@Nuy6
} dhLR#m30T
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public PaginationSupport findPageByCriteria ^@RvCJ+
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(final DetachedCriteria detachedCriteria, finalint UCfouQ Cj
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pageSize, ,3T"fT-(
finalint startIndex){ 4s9@4
return(PaginationSupport) so$(-4(E O
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getHibernateTemplate().execute(new HibernateCallback(){ mHW%:a\L
publicObject doInHibernate Gt*K:KT=L
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(Session session)throws HibernateException { h+j^VsP zB
Criteria criteria = gggD "alDx
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detachedCriteria.getExecutableCriteria(session); |e2s\?nB0S
int totalCount = d wG!]j>:_
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((Integer) criteria.setProjection(Projections.rowCount 3lZl
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()).uniqueResult()).intValue(); nCWoco.xy
criteria.setProjection gFHBIN;u
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(null); S%}G 8Ty
List items = p{LbTjdNc
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criteria.setFirstResult(startIndex).setMaxResults 6wWhM&Wd
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(pageSize).list(); >wmHCOL:
PaginationSupport ps = C 4C/
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new PaginationSupport(items, totalCount, pageSize, i56Rdb
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startIndex); ph6'(,
return ps; tyW}=xs
} uuwJ-
}, true); }lX$KuD
} OHBCanZZ,
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public List findAllByCriteria(final EF\OM?R
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DetachedCriteria detachedCriteria){ *6AV^^
return(List) getHibernateTemplate o
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().execute(new HibernateCallback(){ n8; p]{
publicObject doInHibernate EG`AkWy
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(Session session)throws HibernateException { JZ-@za6u
Criteria criteria = I]W7FZ=o
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detachedCriteria.getExecutableCriteria(session); U?f-/@fc
return criteria.list(); 83R s1}*
} {c_bNYoE
}, true); |"9&F
} 7\98E&
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public int getCountByCriteria(final 0>SA90Q
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DetachedCriteria detachedCriteria){ 6#*_d,xQT
Integer count = (Integer) Mi|13[p{
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getHibernateTemplate().execute(new HibernateCallback(){ Fy<:iv0>t
publicObject doInHibernate 8\P,2RSnt
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(Session session)throws HibernateException { \h#aPG<yo
Criteria criteria = W7uX
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detachedCriteria.getExecutableCriteria(session); :stHc,
return .W~XX
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criteria.setProjection(Projections.rowCount z*jaA;#
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()).uniqueResult(); )u{]rb[
} |=YK2};
}, true); vi^YtA
return count.intValue(); !;&\n3-W
} PVlCj
} o5&b'WUJ=
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用户在web层构造查询条件detachedCriteria,和可选的 3GE;:;8B
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 '9WTz(0?
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l
PaginationSupport的实例ps。 d"?"(Q_8n
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ps.getItems()得到已分页好的结果集 O-V]I0
ps.getIndexes()得到分页索引的数组 Yh1nXkA!V
ps.getTotalCount()得到总结果数 Q<AOc\oO
ps.getStartIndex()当前分页索引 ~HGSA(
ps.getNextIndex()下一页索引 SF;\*]["f
ps.getPreviousIndex()上一页索引 zW#5 /*@
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 )cizd^{
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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 ,5Wu
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一下代码重构了。 Pah@d!%A
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我把原本我的做法也提供出来供大家讨论吧: 5<*ES[S
J61%a,es
首先,为了实现分页查询,我封装了一个Page类: r-$xLe7a
java代码: q>'#; QA
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/*Created on 2005-4-14*/ v]on0Pi!
package org.flyware.util.page; .-HM{6J
};rp25i
/** _ s}aF
* @author Joa NbU4|Oi
* t^MTR6y+8
*/ AcnY6:3Y|
publicclass Page { kBA.N l7
SPlt=*C#_
/** imply if the page has previous page */ W*S4gPGM
privateboolean hasPrePage;
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/** imply if the page has next page */ b(|&e
privateboolean hasNextPage; :F"IOPfU5[
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/** the number of every page */ =\2gnk~
privateint everyPage; am? k
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/** the total page number */ 2Cy,#X%j>
privateint totalPage; e)?}2
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/** the number of current page */ $t& o(]m
privateint currentPage; ]'%
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/** the begin index of the records by the current H%l-@::+$
d:>^]5cE&
query */ (=u!E+N
privateint beginIndex; bnkZWw'9
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/** The default constructor */ *ilVkV"U
public Page(){ q)?!]|pZ
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} [g}#R#Y)
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/** construct the page by everyPage ^"I@ 8 k
* @param everyPage w+')wyB
* */ YBj*c$.D0
public Page(int everyPage){ yI|x
5f
this.everyPage = everyPage; F;`c0ja]
} ]XlBV-@b
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/** The whole constructor */ @0EY5{&
public Page(boolean hasPrePage, boolean hasNextPage, 2dHO!A$RF
I@VzH(da\
{Lv"wec*x
int everyPage, int totalPage, :F6dXW
int currentPage, int beginIndex){ dr"$@
this.hasPrePage = hasPrePage; nl(GoX$vRQ
this.hasNextPage = hasNextPage; 4=^Ha%l
this.everyPage = everyPage; V /\Y(Mxc
this.totalPage = totalPage; g?xXX
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this.currentPage = currentPage; I:DAn!N-A*
this.beginIndex = beginIndex; DFZ0~+rh
} w3
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1l)j(,Zd*
/** 7&P70DO
* @return pFMjfWD,C
* Returns the beginIndex. Jjj;v2uSK
*/ Ppl :_Of
publicint getBeginIndex(){ j|[$P4w}U
return beginIndex; 3r[F1z2B
} _nz_.w0H9
,<P"\W
/** yph@H!@
* @param beginIndex aJ=)5%$6kc
* The beginIndex to set. `Mg3P_}=
*/ l v:GiA"X
publicvoid setBeginIndex(int beginIndex){ 0@{bpc rc
this.beginIndex = beginIndex;
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} 4w9=z,
d5L BL'/o
/** 6v scu2
* @return X6B,Mply
* Returns the currentPage. Qh8pOUD0l}
*/ p3-~cr.LD
publicint getCurrentPage(){ "h1ek*(?<
return currentPage; %$b}o7U"s
} ;s$4/b/~
URj)]wp/
/** O251. hXK
* @param currentPage 8MDivr/@
* The currentPage to set. *^{j!U37s
*/ ,if~%'9j
publicvoid setCurrentPage(int currentPage){ F
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this.currentPage = currentPage;
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} CTg79
ITYk
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/** y"Fu=
* @return -0;{
* Returns the everyPage. !Y|xu07
*/ )R<93`q
publicint getEveryPage(){ "* FjEA6=
return everyPage; ,H?e23G
} a 01s'9Be
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/** +Q5'!@8
* @param everyPage $Sy}im\H
* The everyPage to set. lUq`tK8
*/ 9i_@3OVl
publicvoid setEveryPage(int everyPage){ IY!.j5q8
this.everyPage = everyPage; "UY34a^I
}
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/** p;o "i_!
* @return &'PLOyWw
* Returns the hasNextPage. e)-$#qW
*/ [-W~o.`
publicboolean getHasNextPage(){ 6&~Z3|<e
return hasNextPage; M/F<W!
} 'Q]Wk75
@HI@PZ>
/** &uaSp,L
* @param hasNextPage suaP'0
* The hasNextPage to set. K0'p*[yO/j
*/
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publicvoid setHasNextPage(boolean hasNextPage){ TL"+Iv2]/$
this.hasNextPage = hasNextPage; #NMQN*J>D
} $@^\zg1n
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/** Ai 8+U)
* @return _a$5"
* Returns the hasPrePage. pox;NdX7
*/ Wo9=cYC)
publicboolean getHasPrePage(){ c?c"|.-<p
return hasPrePage; x) %"i)
} *<{hLf
K",Xe>
/** v'`qn
* @param hasPrePage !p36OEx
* The hasPrePage to set. XH!n{Of
*/ d{WOO)j
publicvoid setHasPrePage(boolean hasPrePage){ .}!.:
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this.hasPrePage = hasPrePage; 3h o'\Ysu/
} +Swl$ab
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/** cF9ZnT.
* @return Returns the totalPage. 4},Y0 QXw
* eA(FWO
*/ )`|`PB
publicint getTotalPage(){ /a}N6KUi
return totalPage; Zl!
} #QOb[9(Tu(
kyYU 1gfh
/** ]$UTMuOQl
* @param totalPage ??hKsjNAm0
* The totalPage to set. I&1.}{G>F
*/ i(# Fjp
publicvoid setTotalPage(int totalPage){ R5},E
this.totalPage = totalPage; O#8lJ%?
} X,8Zn06M
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} SBi4i;qD
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'
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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 \`/ P*
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个PageUtil,负责对Page对象进行构造: )iPU
java代码: U~zy;MT
CX{M@x3m
t08[3Q&
/*Created on 2005-4-14*/ aiw4J
package org.flyware.util.page; @@!]Raj=
{pRa%DF
import org.apache.commons.logging.Log; c~\^C_
import org.apache.commons.logging.LogFactory; [>Zg6q|
$['`H)z
/** QS,_= <
(
* @author Joa \D%n8O
* OMjx,@9
*/ Z#;\Rb.x7
publicclass PageUtil { hn&NypI
3Dh{#"88
privatestaticfinal Log logger = LogFactory.getLog 1iM(13jW
d-8g
(PageUtil.class); $iH
4;IZ}9|G
/** >;xkiO>Y
* Use the origin page to create a new page !0X"^VB
* @param page K_X(j$2Xc
* @param totalRecords jfa<32`0E
* @return _Mh..#)`[
*/ =k!F`H`/%'
publicstatic Page createPage(Page page, int 2:[G4
Sc]h^B^7
totalRecords){ @Js@\)P79
return createPage(page.getEveryPage(), S.C7%XU
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page.getCurrentPage(), totalRecords); iNn?G C>
} J,`I>^G
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/** Pn}oSCo
* the basic page utils not including exception Qeq=4Nq
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handler
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* @param everyPage gX5.u9%C\
* @param currentPage [s-!tE3-
* @param totalRecords {]y!2r
* @return page #vcQ =%;O
*/ SR/
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publicstatic Page createPage(int everyPage, int s*>B"#En
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currentPage, int totalRecords){ bde6
;=oM
everyPage = getEveryPage(everyPage); B@vup {Kg
currentPage = getCurrentPage(currentPage); !ZN"(0#qz
int beginIndex = getBeginIndex(everyPage, +ldgT"
aSSw>*?Q
currentPage); Q(hAV
int totalPage = getTotalPage(everyPage, ~?lmkfy
#W L>ha
v
totalRecords); `~qVo4V6Z
boolean hasNextPage = hasNextPage(currentPage, 1lv.@-
lIatM@gU
totalPage); "Z
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boolean hasPrePage = hasPrePage(currentPage); 5PKdMEK|q
E{B40E~4
returnnew Page(hasPrePage, hasNextPage, =XUt?5
everyPage, totalPage, ;q2e[ y
currentPage, n{%[G2.A
d]l(B+\vf
beginIndex); !R$t>X
} 3.04Toq!
[sG!|@r
privatestaticint getEveryPage(int everyPage){ kx[h41|n
return everyPage == 0 ? 10 : everyPage; cvnRd.&
} ^0"[l {
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privatestaticint getCurrentPage(int currentPage){ Z&y9m@
return currentPage == 0 ? 1 : currentPage; /}-LaiS
} &?SU3@3|
O#b%&s"o
privatestaticint getBeginIndex(int everyPage, int -$j|&l
'A#l$pJp7
currentPage){ |+Ub3<b[]
return(currentPage - 1) * everyPage; #xxs^Kbqa#
} gG46hO-M%x
y/Q,[Uzk\
privatestaticint getTotalPage(int everyPage, int +q~dS.
H:L<gv(rG
totalRecords){ ;c>IM]
int totalPage = 0; 4p/d>DTiM
4ko(bW#jL
if(totalRecords % everyPage == 0) =a./HCF
totalPage = totalRecords / everyPage; 7Dx<Sr!
else C5'#0}6i
totalPage = totalRecords / everyPage + 1 ; nOUF<DNQ
!\1Pu|
return totalPage; O<qo%fP
} 6y)NH 8l7
5!d'RBO
privatestaticboolean hasPrePage(int currentPage){ oOy_2fwZPp
return currentPage == 1 ? false : true; j}@n`[V1
} ns !Mqcm
4VfZw\^
privatestaticboolean hasNextPage(int currentPage, 25jgM!QBXF
1bJrEXHXy
int totalPage){ | D,->k
return currentPage == totalPage || totalPage == 7-MkfWH2b6
x-=qlg&EI
0 ? false : true; dy2<b+..
} SH M@H93
$r=tOD4;
/%T d(
} .t|B6n!
VpmD1YSn
G>c:+`KS
,hXhcfFl
Ln5g"g8gb%
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 #x5?RHX56
5KDN8pJN
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 "\M^jO
S-KHot ?
做法如下: >-Q=o,cl%3
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 A"~4|`W
{Zy)p%j8
的信息,和一个结果集List: IH~[/qNk
java代码: 'nh^'i&0.
:Z5Twb3h
xc6A&b>jI
/*Created on 2005-6-13*/ 5\eM3w'd
package com.adt.bo; ; )J\k2
nf9NJ_8}4H
import java.util.List; 16R0#Q/{+*
V'&`JZK6
import org.flyware.util.page.Page; ww$Ec
*b+~@o
/** eww/tG a
* @author Joa "Z*u2_ H
*/ /p_#8}Uh
publicclass Result { E*X-f"
U/3<p8
private Page page; El#"vIg(\
&i?>mt
private List content; ae|j#!~oi
K/ 5U;oC
/** 1=Nh<FuQ
* The default constructor ct![eWsuB
*/ ~zT7 43
public Result(){ R\d)kcy4
super(); <mX EX`?
} Tg~SGAc
|#?:KvU97E
/** #J09Eka;J
* The constructor using fields ZQY?wO: [
* bL]NSD
* @param page |Y&&g=7
* @param content j0+l-]F-
*/ E|v9khN(].
public Result(Page page, List content){ XPQY*.l&.
this.page = page; ;_Z[' %
this.content = content; %d"d<pvx
} C6{\^kG^j2
5>u,Qh
/** )7s(]~z
* @return Returns the content. U/l3C(bc!
*/ sw$$I~21
publicList getContent(){ Ty;P`Uv]r
return content; Ne9S90HsB6
} GPs//
;2jH;$HZ
/** /Mmts=^Ja
* @return Returns the page. Y~[k_!
*/ 5Gw B1}q
public Page getPage(){ pa8R;A70Dl
return page; N>Q~WXvV#
} ^(on"3sG
!b 4v}70,
/** ~duF2m 72
* @param content -h8@B+
* The content to set. y0_z_S#gO
*/ r!e:sJAB.
public void setContent(List content){ AMf{E
this.content = content; Z(:q.{"r
} N83c+vs%c
;G|#i?JJ
/** yeqHeZ
* @param page !
n13B
* The page to set. 5~GH*!h%;
*/ ,zVS}!jRhy
publicvoid setPage(Page page){ ]m<z
this.page = page; >&%#`PKT
} q)PLc{NO
} Bx9v2x.
d.Ep#4
:^H2D=z@
vMYL( ]e
5VZZk%oy
2. 编写业务逻辑接口,并实现它(UserManager, 5DxNHEuS
uyDPWnYk
UserManagerImpl) @P@{%I
java代码: A} v;uNS]
^i8"eF
u%sfHGrH
/*Created on 2005-7-15*/ hh7unHt-
package com.adt.service; {j[a'Gb
JBk >|q"
import net.sf.hibernate.HibernateException; ^aR^M\38
[]b=
xRJM
import org.flyware.util.page.Page; T7R,6qt
r%\%tz'`j
import com.adt.bo.Result; eY\w?pT2
$q*hE&x
Qd
/** C8t;E`
* @author Joa I_\?w SNGM
*/ =M9;`EmC
publicinterface UserManager { A"i$.dR{
MnTJFo"
public Result listUser(Page page)throws R@~=z5X(Q
.OcI.1H [
HibernateException; ex6QHUQ
*b8AN3!
} K( r@JW
c"lblt5
QERj`/g
w:aV2
Z;~ 7L*|
java代码: S\L^ZH?[2
H/}W_ h^^
#5%ipWPHb
/*Created on 2005-7-15*/ O;+
sAt
package com.adt.service.impl; U%)-_
*`z
^C'{# p"
import java.util.List; j:E3c\a
=z!/:M
import net.sf.hibernate.HibernateException; @Y !Jm
ek1<9"y
import org.flyware.util.page.Page; Q6;bORN
import org.flyware.util.page.PageUtil; =$SvKzN
GB4^ 4Ajx
import com.adt.bo.Result; B&m6N,
import com.adt.dao.UserDAO; . ZP$,
import com.adt.exception.ObjectNotFoundException; yT|44
D2j
import com.adt.service.UserManager; N qS]dH61
r;_*.|AH
/** GBY{O2!3u
* @author Joa _$_,r H
*/ ,H>'1~q
publicclass UserManagerImpl implements UserManager { mO2u9?N
'*D>/hn|:]
private UserDAO userDAO; lYT_Y.%I
MY'T%_id
/** $Y M(NC
* @param userDAO The userDAO to set. C#n.hgo>I
*/ @%jY
publicvoid setUserDAO(UserDAO userDAO){ c 5 `74g
this.userDAO = userDAO; U".5x~UC
} W`uq,r0Xsy
;FJFr*PM
/* (non-Javadoc) [>KnMi=o)
* @see com.adt.service.UserManager#listUser CbwQbJ/v7
Pk>S;KT.
(org.flyware.util.page.Page) nK}-^Ur
*/ <%.lPO]&E
public Result listUser(Page page)throws j'`-3<k
KW!+Ws
HibernateException, ObjectNotFoundException { gx8i|]
int totalRecords = userDAO.getUserCount(); Tvt(nWn(H1
if(totalRecords == 0) 5Od&-~O
throw new ObjectNotFoundException t;`ULp~&
/ke[nr
("userNotExist"); Z7> Nd$E{
page = PageUtil.createPage(page, totalRecords); E24j(>
List users = userDAO.getUserByPage(page); i.{.koH<
returnnew Result(page, users); Rn)fwGC
} OIDP#K
rl,i,1t
} 86);0EBX
|
{Q}:_/q
3YG%YhevO
$,B;\PX
q07H{{h/B
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 i*r ag0Mw
Z*Rgik
询,接下来编写UserDAO的代码: k"|Fu
3. UserDAO 和 UserDAOImpl: wI;sZJc
java代码: 6F5g2hBz
EQ.K+d*K][
P *&Cght>0
/*Created on 2005-7-15*/ my0iE:
package com.adt.dao; 1Tr%lO5?6
=RAojoN
import java.util.List; ^B1$|C
D,
>pp#>{}
import org.flyware.util.page.Page; @,9YF}
Z/T(4
import net.sf.hibernate.HibernateException; tSe[*V4{'
XRHngW_A
/** yb,X
}"Et
* @author Joa
vR&b2G7o
*/ !#zO%
publicinterface UserDAO extends BaseDAO { p[&b@U#
oJQ
\?~
publicList getUserByName(String name)throws z;MPp#Y
D8{,}@
HibernateException; U }AIOtUw
6Yc(|>b!
publicint getUserCount()throws HibernateException; 'j-U=2,n
jYvl-2A'
publicList getUserByPage(Page page)throws Z1Qv>@u
K>C@oE[W
HibernateException; 0Y:)$h2?
$ w+.-Tr
} =sAU5Ag68
Z*ag{N
r`\@Fv,
fjy7 gC2
[jksOC)@4
java代码: `sDLxgwI
x6^Y&,y9kU
@AM11v\:
/*Created on 2005-7-15*/ e)N<r
package com.adt.dao.impl; +z:>Nl
/4N ?v. jf
import java.util.List; hiEYIx
mkhWbzD'S
import org.flyware.util.page.Page; _8!x
0X4)=sJP
import net.sf.hibernate.HibernateException; 7&9w_iCkV
import net.sf.hibernate.Query; slhMvHOk-
~KV{m
import com.adt.dao.UserDAO; *nc3A[B#C
q6 ny2;/r
/** Zd88+GS,#
* @author Joa d3Y;BxEz
*/ p<z eaf0W
public class UserDAOImpl extends BaseDAOHibernateImpl 5S,Kq35$(
)8oN$20
implements UserDAO { J_fs}Y1q\
O#t[YP
/* (non-Javadoc) dPbn[*:
* @see com.adt.dao.UserDAO#getUserByName ~9xkiu5~
^d@2Y0hH
(java.lang.String) tRO=k34
*/ Zw _aeJ
publicList getUserByName(String name)throws KCAV
#C~ </R%
HibernateException { c*]f#yr?
String querySentence = "FROM user in class g cB
hEw
^b|I^TN0
com.adt.po.User WHERE user.name=:name"; h"/'H)G7_&
Query query = getSession().createQuery
2W`WOBz
Xs# _AX
(querySentence); JWYe~
query.setParameter("name", name); J@"UFL'^
return query.list(); ,RM8D)m\
} \I-e{'h
#p7gg61
/* (non-Javadoc) QqRF?%7q"q
* @see com.adt.dao.UserDAO#getUserCount() cTS.yN({G
*/ \#WWJh"W
publicint getUserCount()throws HibernateException { jvAjnh#
int count = 0; ;]b4O4C\
String querySentence = "SELECT count(*) FROM DA04llX~
5!cp^[rGL
user in class com.adt.po.User"; Sc#3<nVg
Query query = getSession().createQuery @}:E{J#g
?qi~8.<w
(querySentence); :WX
OD
count = ((Integer)query.iterate().next u|T]Ne
/zb/am1#
()).intValue(); (z.n9lkfi
return count; 97$Q?a8S@
} KO%$
W$2\GPJt
/* (non-Javadoc) Kh[l};/F
* @see com.adt.dao.UserDAO#getUserByPage ~,E }^
SDV#p];u
(org.flyware.util.page.Page) LMx/0
*/ $v[mIR
publicList getUserByPage(Page page)throws S89j:KRXH%
%p$XK(6
HibernateException { vd(S&&]o1
String querySentence = "FROM user in class _p5#`-%mM
5S2 j5M00
com.adt.po.User"; /d,u"_=l
Query query = getSession().createQuery ~*"ZF-c,
C:}1r
(querySentence); T/2k2r4PD
query.setFirstResult(page.getBeginIndex()) ]jC{o,?s
.setMaxResults(page.getEveryPage()); h# KSKKNW
return query.list(); eY'nS
} 4L ]4WVc
`GW&*[.7
} |59)6/i
sNcU>qjj6
p
JT)X8K"
/]'&cD 1
od5nRb
至此,一个完整的分页程序完成。前台的只需要调用 m;\nMdn
jf`w8*R
userManager.listUser(page)即可得到一个Page对象和结果集对象 =}kISh
FU/:'/ L
的综合体,而传入的参数page对象则可以由前台传入,如果用 4w=v
/WDo
fM7B<eB
webwork,甚至可以直接在配置文件中指定。 sve} ent
/3Gq&[R{
下面给出一个webwork调用示例: yYYP;N?g4k
java代码: tpEy-"D&
wpt$bqs|1
nW"O+s3
/*Created on 2005-6-17*/ VevG 64o
package com.adt.action.user; K-)!d$$
gd]S;<Jh
import java.util.List; HcJ!(
o$l8"Uv
import org.apache.commons.logging.Log; =0]K(p,
import org.apache.commons.logging.LogFactory; y6tqemz
import org.flyware.util.page.Page; L.yM"
UPr&
`kaJ
import com.adt.bo.Result; d~r A`!s7`
import com.adt.service.UserService; &9)/"
import com.opensymphony.xwork.Action; 036m\7+Qj
5,s@K>9l;
/** F-rhxJd
* @author Joa ZD'mwj+K
*/ `h'l"3l
publicclass ListUser implementsAction{ )^ZC'[93
K>e-IxA);0
privatestaticfinal Log logger = LogFactory.getLog >6jal?4u-
V^R,j1*
(ListUser.class); k{#k:
)Z1&`rv
private UserService userService; 9aLd!PuTN
gC(S(osF
private Page page; 3N-
'{c6]U
_s#]WyU1g
privateList users; )Sb-e(sl
<mlN\BcX;
/* l+>Y
* (non-Javadoc) JygJ4RI%j
* {l!{b1KJ
* @see com.opensymphony.xwork.Action#execute() h)ZqZ'k$
*/ jT$J~MpHh
publicString execute()throwsException{ 6xtgnl#T
Result result = userService.listUser(page); uA[
:
page = result.getPage(); TP {\V>*Yz
users = result.getContent(); CEkUXsp
return SUCCESS; bRyxP2
} 2(0%{*m
1E
/G+pm
/** qpjZ-[UC
* @return Returns the page. (}6\_k[}m
*/ MnqT?Cc4$j
public Page getPage(){ _q#pEv
return page; EjFpQ|-L|
} dWiNe!oY2
P ?f${t+
/** bAH<h
* @return Returns the users. o*/;Zp==
*/ 7F0J*M
publicList getUsers(){ A :KZyd"Z
return users; )Cj1VjAg
} M0xhcU_
HM0&%
/** WwTl|wgvyI
* @param page M>m!\bb%.
* The page to set. @@K/0:],
*/ Vdxo
publicvoid setPage(Page page){ `r-Jy{!y4
this.page = page; vJGH8$%;,
}
anpKWa
FCEmg0qdjD
/** "Y L^j~A
* @param users t?-a JU
* The users to set. r'#!w3*Cy
*/ Qd YYWD
publicvoid setUsers(List users){ u28$V]
this.users = users; \3^V-/SJf
} ],0I`!\
cL*oO@I&_
/** R/"-r^j
* @param userService ;f[##=tm
* The userService to set. 3Fn}nek
*/ ejyx[CF
publicvoid setUserService(UserService userService){ 9q$^x/z!
this.userService = userService; I*Dj@f`
} As>Og
} s<# BxN
h7fytO
|3E|VGm~
//|B?4kk
*j]Bo,AC
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, AQ(n?1LU
2IW!EUR
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 0]*W0#{Zj
0nCiN;sA
么只需要: b3[[ Ah-
java代码: Cq/u$G
n:wAxU
]zyT_}&
<?xml version="1.0"?> q?mpvpLG
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork "IQYy~
/
>SvS(N{
1.0//EN" "http://www.opensymphony.com/xwork/xwork- Io JI|lP
.wq
j
1.0.dtd"> (nmsw6
X
goyDG/
<xwork> zF^H*H
.hxFFk%5
<package name="user" extends="webwork- v&;JVai
5lD`qY
interceptors"> YHom9&A
K<::M3eQ
<!-- The default interceptor stack name dF 6od
*q=\e 9
--> 7J5jf231
<default-interceptor-ref =|Qxv`S1
n=JV*h0
name="myDefaultWebStack"/> kG5+kwV=:
o:ow"cOEf
<action name="listUser" u? >x
Q.eD:@%iE
class="com.adt.action.user.ListUser"> 8(Ptse
,
<param >gL&a#<S
.!L{yU,
name="page.everyPage">10</param> "O9n|B
<result HxW/t7Z(
l
lcq~*zz
name="success">/user/user_list.jsp</result>
Nb3O>&J
</action> x?B`p"ifS
rp<~=X
</package> v)O].Hd
W0mvwYON[
</xwork> h(AL\9{=}
R"HV|Dm|m
`u_MdB}<x;
&F#eYEuy
eQ)*jeD
+RM!j9Rq
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 MHt
~ZVH
$v2t6wS,"
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 jf1GYwuW*
PE6,9i0ee
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 /^jl||'H,:
_ ~yd
EX!`Zejf
xbw;s}B
u@:[ dbJ
我写的一个用于分页的类,用了泛型了,hoho K@2"n|
S;
Z-4/xi7
java代码: Q6URaw#Yt`
t+F_/_"B
?MSwr_eZH
package com.intokr.util; ~ehN%-
NQuqM`LSQ
import java.util.List; `_1fa7,z
?RsPAL
/** x\ #K2
* 用于分页的类<br> p>J@"?%^
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 9S9j
* 6A=k;do
* @version 0.01 xH`
VX-X3
* @author cheng gzvgXZ1q"
*/ 1'p=yHw
public class Paginator<E> { LcA7f'GVK
privateint count = 0; // 总记录数
<6;@@
privateint p = 1; // 页编号 ^+d]'$
privateint num = 20; // 每页的记录数 wE<r'
privateList<E> results = null; // 结果 J[uH@3v
#/H2p`5
/** ~;]zEq-hG
* 结果总数 TUwX4X6m
*/ N8kNi4$mp=
publicint getCount(){ V'dw=W17V
return count; m##!sF^k~J
} KrG,T5
NhTJB7
publicvoid setCount(int count){ >iG3!Td)y
this.count = count; -@]b7J?`k
} $.w$x1
C,mfA%63
/** ..BP-N)V)
* 本结果所在的页码,从1开始 j$s/YI:
* j$lf>.[I
* @return Returns the pageNo.
O<|pw
*/ * Wp?0CP
publicint getP(){ \I}EWI
return p; ^ZS!1%1
} @x!+_z
,H.5TQ#
/** 4:**d[|1
* if(p<=0) p=1 +hispU3ia
* OXKV6r6f
* @param p d)Z&_v<|
*/ umnQ$y
0
publicvoid setP(int p){ =w`uZ;l$Q
if(p <= 0) w 2U302TZ
p = 1; n`w]? bL
this.p = p; Pe\Obd8d
} q o^mp
~UeTV?)
/** XHJ`C\xR
* 每页记录数量 YIgHLM(
*/ \ %MsG
publicint getNum(){ <z#Fj`2{
return num; -L6CEe
} T2rBH]5
iV#A-9
/** kQd|qZ=:w
* if(num<1) num=1 /|H9Gm
*/ 7mXXMm
publicvoid setNum(int num){ zAklS 7L
if(num < 1) L{r 4hL [
num = 1; kc=Z6(=
this.num = num; L$);50E
} Uzrf,I[
6L\]Ee
/** zd!%7
UP
* 获得总页数 xb0,dZb
*/ #%E^cGfY
publicint getPageNum(){
!j%
return(count - 1) / num + 1; (=c,b9cb
} b$*2bSdv0<
W|zPV`
/** o_k)x3I?
* 获得本页的开始编号,为 (p-1)*num+1 r1vS~
4Z
*/ Dic|n@_Fy
publicint getStart(){ HYT~AO-!
return(p - 1) * num + 1; $- %um
} EN/t5d
dy5}Jn%L
/** kn$_X4^?
* @return Returns the results. HRM-r~2:-]
*/ -gt?5H h
publicList<E> getResults(){ oyk&]'>
return results; .b<W*4{j0H
} kFmtE
dhsc
<,/7:n
public void setResults(List<E> results){ z6d0Y$A G
this.results = results; %3t;[$n#
} xHaz*w1|
/2/aMF(J
public String toString(){ 5=#d#dDc
StringBuilder buff = new StringBuilder emrA!<w!W
NR8`nc1~
(); P3=#<Q.
buff.append("{"); lP]Y^Gz
buff.append("count:").append(count); G'w!Aw s
buff.append(",p:").append(p); ?)k]Vg.
buff.append(",nump:").append(num); \.H9e/vU`
buff.append(",results:").append >!']w{G
z^&$6c_
(results); Tl[*(|/C
buff.append("}"); f#GMJ mCQs
return buff.toString(); hjFht+j1
} @>~\So|
HB}rpiB
} RU6c 8>"
sb8bCEm-\
7_)38