Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 |+Ub3<b[]
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 z
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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 ^/Frg<>'p
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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 *5S~@
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分页支持类: ;jT@eBJ
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java代码: k*= #XbX
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package com.javaeye.common.util; oyo
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import java.util.List; }JBLzk5|
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publicclass PaginationSupport { +#
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publicfinalstaticint PAGESIZE = 30; #ZpR.$`k
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privateint pageSize = PAGESIZE; ;*8,PV0b_<
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privateList items; I> 3]VRi
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privateint totalCount; LO
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privateint[] indexes = newint[0]; [>U =P`
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privateint startIndex = 0; zvnR'\A_
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public PaginationSupport(List items, int XSz)$9~hk
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totalCount){ .Zv uhOn^
setPageSize(PAGESIZE); Q96^rjY
setTotalCount(totalCount); iwT
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setItems(items); 5IiZnGu
setStartIndex(0); d,caO E8N
} JQ]A"xTIa*
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public PaginationSupport(List items, int )Fh5*UC
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totalCount, int startIndex){ E >lW'
setPageSize(PAGESIZE); ;B!u=_'
setTotalCount(totalCount); YA%0{Tdxz
setItems(items);
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setStartIndex(startIndex); *k
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} *b+~@o
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public PaginationSupport(List items, int "Z*u2_ H
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totalCount, int pageSize, int startIndex){ E*X-f"
setPageSize(pageSize); U/3<p8
setTotalCount(totalCount); El#"vIg(\
setItems(items); 3Ja1|;(2
setStartIndex(startIndex); &x<y4ORH|
} ?hS&OtW
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publicList getItems(){ eJwHeG
return items; *3]_Huw<
} vX/("[
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publicvoid setItems(List items){ :927y
this.items = items; &pZncm
} RYuR&0_{
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publicint getPageSize(){ !U8n=A#,-
return pageSize; >crFIkOJ
} _/`H<@B_U
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publicvoid setPageSize(int pageSize){ 9S]]KEGn4
this.pageSize = pageSize; Cmj+>$')0
} Yb;$z'
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publicint getTotalCount(){ >qC,IQ'
return totalCount; r`GA5}M
} 5isqBu
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publicvoid setTotalCount(int totalCount){ *$yU|,
if(totalCount > 0){ 's_[#a;Vp
this.totalCount = totalCount; @ UCr`>
int count = totalCount / ;fGh]i
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pageSize; Vx*O^cM
if(totalCount % pageSize > 0) ].r~?9'/
count++; {IA3`y~
indexes = newint[count]; f*46,`x
for(int i = 0; i < count; i++){ T_/ n#e
indexes = pageSize * 0l+[[ZTV
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} -h8@B+
}else{ Cu&y',ee~
this.totalCount = 0; #$0*Gd-N
} d !=AS
} ?3=y]Vb+
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publicint[] getIndexes(){ ,A9_xdv5
return indexes; '
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} x,: DL)$1
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publicvoid setIndexes(int[] indexes){ Dlqvz|X/
this.indexes = indexes; "cD MFu
} 5e}adHjM
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publicint getStartIndex(){ ^LAnR>mz^r
return startIndex; &Xh_`*]ox
} &.1qixXIr
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publicvoid setStartIndex(int startIndex){ ^Cy=L]
if(totalCount <= 0) s@D/.X
this.startIndex = 0; uyDPWnYk
elseif(startIndex >= totalCount) <`'T#e$
this.startIndex = indexes 5/YGu=,
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[indexes.length - 1]; u%sfHGrH
elseif(startIndex < 0) :`>bh
this.startIndex = 0; {j[a'Gb
else{ JBk >|q"
this.startIndex = indexes ^aR^M\38
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[startIndex / pageSize]; 45A|KaVpg
} gJBw6'Z
} v+(-\T\i
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publicint getNextIndex(){ I_\?w SNGM
int nextIndex = getStartIndex() + ^2C
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pageSize; MnTJFo"
if(nextIndex >= totalCount) !q!5D`
return getStartIndex(); h,|. qfUk
else >["X(%&w
return nextIndex; *b8AN3!
} <%?!3 n*
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publicint getPreviousIndex(){ QERj`/g
int previousIndex = getStartIndex() - w:aV2
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pageSize; S\L^ZH?[2
if(previousIndex < 0) H/}W_ h^^
return0; bJoP@s
else O;+
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return previousIndex; L(o#)I>j
} Ubm]V{7
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} ^C'{# p"
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抽象业务类 |.;*,bb|3
java代码: t?wVh0gT
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/** @%BsQm
* Created on 2005-7-12 4^T_" W}
*/ z1nKj\AM2
package com.javaeye.common.business; "7J38Ej\
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import java.io.Serializable; ^cCNQS}r
import java.util.List; ?7uK:'8
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import org.hibernate.Criteria; X`28?
import org.hibernate.HibernateException; NA=m<n#
import org.hibernate.Session; 4*'ZabDD
import org.hibernate.criterion.DetachedCriteria; J,:Wv`N:9~
import org.hibernate.criterion.Projections; 4s6,`-
import hc*t Q2
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org.springframework.orm.hibernate3.HibernateCallback; 08+\fT [
import C#n.hgo>I
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org.springframework.orm.hibernate3.support.HibernateDaoS SP"t2LTP
*Hz]<b?
upport; fd$nAE
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import com.javaeye.common.util.PaginationSupport; 9[R+m3V/`
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public abstract class AbstractManager extends p
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HibernateDaoSupport { nK}-^Ur
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privateboolean cacheQueries = false; KW!+Ws
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privateString queryCacheRegion; ^l<!:SS
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publicvoid setCacheQueries(boolean pS2u&Y"u|
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cacheQueries){ Pkv+^[(4
this.cacheQueries = cacheQueries; f>|Wd;7l:
} + w'q5/`
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publicvoid setQueryCacheRegion(String CEAmb[h
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queryCacheRegion){ 9_O6Sl
this.queryCacheRegion = Gk
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queryCacheRegion; NQA2usb
} =]S,p7* 7
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publicvoid save(finalObject entity){ %C_c%3d
getHibernateTemplate().save(entity); kbo9nY1k
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} Hb/8X
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publicvoid persist(finalObject entity){ a$\Bt_
getHibernateTemplate().save(entity); H@b4(6
} Xzl$Qc
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publicvoid update(finalObject entity){ {eVv%sbq
getHibernateTemplate().update(entity); `O5427Im
} -@ra~li,yQ
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publicvoid delete(finalObject entity){ I^HwXp([
getHibernateTemplate().delete(entity); djqw5kO:R
} |*^}e54
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publicObject load(finalClass entity, 7Ck3L6J#
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finalSerializable id){ X]o"4#CQIX
return getHibernateTemplate().load a?xZsR
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(entity, id); n5z|@I`S_
} 5WvsS(
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publicObject get(finalClass entity, ^#IE
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finalSerializable id){ Z1Qv>@u
return getHibernateTemplate().get 4;Vi@(G)
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(entity, id); GG"6O_
} 2x<!>B
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publicList findAll(finalClass entity){ L6#4A3yh
return getHibernateTemplate().find("from 0wCQPvO
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" + entity.getName()); A!Tm[oqu
} *(qj!U43
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publicList findByNamedQuery(finalString mZM,"Wq,
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namedQuery){ s4QCun~m
return getHibernateTemplate )%PMDG|
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().findByNamedQuery(namedQuery);
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} 3@:O1i
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publicList findByNamedQuery(finalString query, dS\!tdHP-Q
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finalObject parameter){ @biU@[D
return getHibernateTemplate -+M360
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().findByNamedQuery(query, parameter); i"xV=.
} {> <1K6t
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publicList findByNamedQuery(finalString query, 5S,Kq35$(
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finalObject[] parameters){ J_fs}Y1q\
return getHibernateTemplate Pd-LDs+Ga
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().findByNamedQuery(query, parameters); s 0_*^cZ
} (> _Lb
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publicList find(finalString query){ )EQz9
return getHibernateTemplate().find v~yw-}fk%
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(query); KVh#"]<WV
} {bR2S&=OmK
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publicList find(finalString query, finalObject _RUL$Ds
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parameter){ hlZ{bO'f
return getHibernateTemplate().find IC (:RtJ
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(query, parameter); jm@,Ihz=wI
} G.^)5!By
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public PaginationSupport findPageByCriteria I$p1^8~L
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(final DetachedCriteria detachedCriteria){ oK
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return findPageByCriteria REYvFx?i
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ck%YEMs
} Vo+.s#wN`h
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public PaginationSupport findPageByCriteria {Z7ixc523
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(final DetachedCriteria detachedCriteria, finalint dJ/gc"7aO
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startIndex){ ,Q3OQ[Nmh
return findPageByCriteria ivn2
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(detachedCriteria, PaginationSupport.PAGESIZE, !icI Rqcf=
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startIndex); s^SU6P/]
} "(vK.-T
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public PaginationSupport findPageByCriteria 2~l7WW+lx,
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(final DetachedCriteria detachedCriteria, finalint rsLkH&aM
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pageSize, MG~Z)+g=y
finalint startIndex){ Rd5-ao4
return(PaginationSupport) X 6tJ
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getHibernateTemplate().execute(new HibernateCallback(){ JN4gH4ez)
publicObject doInHibernate e^3D`GA
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(Session session)throws HibernateException { ok0ZI>=,
Criteria criteria = |m6rF7Q
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detachedCriteria.getExecutableCriteria(session); 0nL
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int totalCount = Yj*T'<e
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((Integer) criteria.setProjection(Projections.rowCount '|Bk}pl7
:Yn.Wv-
()).uniqueResult()).intValue(); 6i~|<vcSP
criteria.setProjection /9&!u )+
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(null); `2LmLFkb
List items = 2G$px
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criteria.setFirstResult(startIndex).setMaxResults 'I+S5![<
'W4B
(pageSize).list(); r~YBj>}
PaginationSupport ps = t&EizH$
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new PaginationSupport(items, totalCount, pageSize, m_CWVw
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startIndex); YY :{/0?
return ps; yn$1nt4
} iE
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}, true); xw_klHL-o
} pe0ax-Zv
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public List findAllByCriteria(final T4Vp0i
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DetachedCriteria detachedCriteria){ R]e&JoY
return(List) getHibernateTemplate A[^#8evaK
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().execute(new HibernateCallback(){ k ,ldi
publicObject doInHibernate G+Z ,ic
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(Session session)throws HibernateException { #b;k+<n[X
Criteria criteria = mRRZ/m?A(
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detachedCriteria.getExecutableCriteria(session); E:B"!Y6
return criteria.list(); gaz",kK<
} hnB`+!
}, true); xvl{o
} {<@ud0A:\
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public int getCountByCriteria(final W_E^+Wl@
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DetachedCriteria detachedCriteria){ 6E
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Integer count = (Integer) 5,##p"O(
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getHibernateTemplate().execute(new HibernateCallback(){ IqFcrU$4
publicObject doInHibernate I:/|{:5
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(Session session)throws HibernateException { "{qnm+G
Criteria criteria = "qF/7`e[
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detachedCriteria.getExecutableCriteria(session); jT$J~MpHh
return F nXm;k,9*
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criteria.setProjection(Projections.rowCount YW6a?f^!
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()).uniqueResult(); iY$iL<
} E56
}, true); 6'kQ(r>
return count.intValue(); 0$c(<+D
} e
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} B !,&{[D
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用户在web层构造查询条件detachedCriteria,和可选的 keRLai7h
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 7F0J*M
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PaginationSupport的实例ps。 RHn3\N
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ps.getItems()得到已分页好的结果集 G .<0^q,
ps.getIndexes()得到分页索引的数组 LYL_Ah'=
ps.getTotalCount()得到总结果数 XZ]ji9'
ps.getStartIndex()当前分页索引 !;(Wm6~*ad
ps.getNextIndex()下一页索引 h[iO'Vq
ps.getPreviousIndex()上一页索引 iYvzZ7
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 '}(>s%~
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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 !ITM:%
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一下代码重构了。 A|1xK90^XT
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我把原本我的做法也提供出来供大家讨论吧: >'q]ypA1
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首先,为了实现分页查询,我封装了一个Page类: Z3c\}HLY
java代码: _[z)%`kay
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/*Created on 2005-4-14*/ syg{qtBz^
package org.flyware.util.page; N[3Y~HX!q
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/** !Whx^B:
* @author Joa K)
* qGH[kd
*/ )@I] Rk?
publicclass Page { 9y&;6V.'
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/** imply if the page has previous page */ 0nCiN;sA
privateboolean hasPrePage; 2e1%L,y{W
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({
/** imply if the page has next page */ j0+D99{R
privateboolean hasNextPage; e#k rr
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/** the number of every page */ KJOb1MM
privateint everyPage; #tHYCSr]
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/** the total page number */ 'D`lVUB
privateint totalPage; qGV(p}$O
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/** the number of current page */ +u=VO#IA#
privateint currentPage; d2i?FT>
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/** the begin index of the records by the current wT- -i@@
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query */ k6z
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privateint beginIndex; qS! Lt3+
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/** The default constructor */ zE1=P/N
public Page(){ QnBWZUI
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} ;%
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/** construct the page by everyPage FIfLDT+ Wh
* @param everyPage ~E8/m_> rU
* */ f?=0Wzb
public Page(int everyPage){ m%})H"5
this.everyPage = everyPage; /~WBqcl
} z7XI`MZN^
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/** The whole constructor */ 0iM'),v[]
public Page(boolean hasPrePage, boolean hasNextPage, 9v;[T%%
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int everyPage, int totalPage, g||
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int currentPage, int beginIndex){ > O?<?
this.hasPrePage = hasPrePage; .YvIVQ
this.hasNextPage = hasNextPage; 5655)u.N8
this.everyPage = everyPage; XX90Is
this.totalPage = totalPage; X,G"#j^
this.currentPage = currentPage; ^4,LIIUj
this.beginIndex = beginIndex; !mqIq}h
} X=f %!
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/** vs+aUT C\
* @return ^CQp5k p]
* Returns the beginIndex. QA^FP8!j
*/ /SM 7t_
publicint getBeginIndex(){ ?o6#i 3k#'
return beginIndex; eB9&HD:
} zBq&/?
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/** Y=Ic<WHR
* @param beginIndex ^fO9oPM|
* The beginIndex to set. KwaxNb5
*/ ztHx)
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publicvoid setBeginIndex(int beginIndex){ }BT0dKx
this.beginIndex = beginIndex; 0/|Ax-dK
} sl@>GbnS
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/** TYR \K
* @return HbPn<x^7
* Returns the currentPage. 4Ng:7C2
*/ jHE^d<=O^
publicint getCurrentPage(){ z#`Qfvu6Hi
return currentPage; tUOY`]0
} Nc[N 11?O
t OJyj49^a
/** %ueD3;V
* @param currentPage j-"34
* The currentPage to set. N8kNi4$mp=
*/ V'dw=W17V
publicvoid setCurrentPage(int currentPage){ m##!sF^k~J
this.currentPage = currentPage; -~JYfj@
} cVMRSp
tcl9:2/^]
/** SvkCx>6/G
* @return nIL67&
* Returns the everyPage. B:UM2Jl
*/ KlS#f
publicint getEveryPage(){ "Vl4=W)u
return everyPage; :Sd`4"AA
} sz/^Ie-~
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/** 8_Uhh5[
* @param everyPage m:0[as=
* The everyPage to set. 3'i(wI~<[
*/ %LmsywPPp
publicvoid setEveryPage(int everyPage){ s3@mk\?qMe
this.everyPage = everyPage; P4{~fh (
} E8nj_^Z
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/** :/$_eg0A
* @return o+XQMg
* Returns the hasNextPage. `x >6Wk1
*/ n`w]? bL
publicboolean getHasNextPage(){ H
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return hasNextPage; ?tqJkL#
} YjL'GmL<
v?,@e5GZ
/** I][&*V1
* @param hasNextPage !J@!2S9
* The hasNextPage to set. 5#X R1#`
*/ q7soV(P
publicvoid setHasNextPage(boolean hasNextPage){ KkpbZ7\@
this.hasNextPage = hasNextPage; >O
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} (@!K tW
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/** }f}? |&q
* @return `[}X_d 1A
* Returns the hasPrePage. [~\]<;;\
*/ IqepR
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publicboolean getHasPrePage(){ PXtF#,roP
return hasPrePage; 3XDU(#
} }hg2}g99
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/** GBpdj}2=
* @param hasPrePage KDP4 7A
* The hasPrePage to set. $-t@=N@vO?
*/ 3pW4Ul@e
publicvoid setHasPrePage(boolean hasPrePage){ H-u
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this.hasPrePage = hasPrePage; d2gYBqag
} rMjb,2*rC7
kF,ME5%
/** /)K;XtcN
* @return Returns the totalPage. j%bC9UkE3
* 5cU:wc
*/ Rcw[`q3/
publicint getTotalPage(){ T!41[vm(
return totalPage; Ck%if
} Q_iN/F
:X-S&SX0
/** XSK<hr0m
* @param totalPage ^=5y;
* The totalPage to set. ~&MDfpl
*/ ,~1k:>njY~
publicvoid setTotalPage(int totalPage){ > cWE@P
this.totalPage = totalPage; ]e"!ZR?XJ
} ,!%E\`
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} 7
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 , u%V%
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个PageUtil,负责对Page对象进行构造: `\;Z&jlpT
java代码: -+Yark
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/*Created on 2005-4-14*/ ?r8hl.Z>
package org.flyware.util.page; X?< L<:.
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import org.apache.commons.logging.Log; k_1@?&3
import org.apache.commons.logging.LogFactory; lic-68T
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/** x@bqPZ t
* @author Joa r[;d.3jtP
* X;)/<:mX
*/ yx4pQL7
publicclass PageUtil { g:y4C6b
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privatestaticfinal Log logger = LogFactory.getLog k[a<KbS
{}Is&^3Z
(PageUtil.class); aD'Ax\-
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/** ^QJJ2 jZ
* Use the origin page to create a new page +s8R]3NJ_H
* @param page Xfqin4/jC
* @param totalRecords 3^y<Db
* @return 2@2d
|
*/ D g0rVV6c
publicstatic Page createPage(Page page, int ;i?2^xe^~c
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totalRecords){ UXpp1/d|e
return createPage(page.getEveryPage(), vF'>?O?
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page.getCurrentPage(), totalRecords); Qb/:E}h]$
} "Z,T%]
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/** `W~
* the basic page utils not including exception x`@`y7(
3rMJC\h
handler .RFH@''
* @param everyPage >8OY6wb
* @param currentPage 5.&)hmpg
* @param totalRecords vGh>1U:
* @return page 2/s42
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*/ Jkbeh.
publicstatic Page createPage(int everyPage, int 'plUs<A
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currentPage, int totalRecords){ N5sVRL"7
everyPage = getEveryPage(everyPage); GxG~J4
currentPage = getCurrentPage(currentPage); ]|,}hsN
int beginIndex = getBeginIndex(everyPage, rEj[XK
)qbkKCq/FB
currentPage); ~v pIy -
int totalPage = getTotalPage(everyPage, (Ll'j0]k>
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totalRecords); b$#b+G{y
boolean hasNextPage = hasNextPage(currentPage, S-gO
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totalPage); P3|s}&
boolean hasPrePage = hasPrePage(currentPage); h
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a <?~1pWtc
returnnew Page(hasPrePage, hasNextPage, vFntzN>#
everyPage, totalPage, a oU"
currentPage, W~D_+[P|_
u|Mx}
beginIndex); =|IlORf<
} [{u3g4`}
v7./u4S|V
privatestaticint getEveryPage(int everyPage){ LFHJj-nk
return everyPage == 0 ? 10 : everyPage; =_|G q|
} ml1%C%
|M5#jVXj
privatestaticint getCurrentPage(int currentPage){ [yQ%g;m
return currentPage == 0 ? 1 : currentPage; lbIPtu
} XJ3sqcS
.|R4E
privatestaticint getBeginIndex(int everyPage, int N\|z{vn
bK~Toz<k
currentPage){ *OFG3 uM
return(currentPage - 1) * everyPage; &U|c=$!\
} !vR Zh('R
b- t
privatestaticint getTotalPage(int everyPage, int `}=R
Qm[s"pM
totalRecords){ W>d)(
int totalPage = 0; %ZWt 45A
9ABU^ig
if(totalRecords % everyPage == 0) HV/:OCK
totalPage = totalRecords / everyPage; ^OWG9`p+
else h`1<+1J9
totalPage = totalRecords / everyPage + 1 ;
Fl=H5HR
UiH7
return totalPage; h^tCF=S
} a6DR' BC
xLoQ0rt
6
privatestaticboolean hasPrePage(int currentPage){ X7L:cVBg
return currentPage == 1 ? false : true; [I4MK%YQ
} ~d]v{<3
SU~.baP?
privatestaticboolean hasNextPage(int currentPage, ~i%=1&K&`
QWfSm^
t
int totalPage){ <O'U-.
Gc
return currentPage == totalPage || totalPage == >rEZ$h
naf ~#==vc
0 ? false : true; ySO\9#Ho
} 9c)#j&2?H
;Hk3y+&]a
(wZ!OLY%}
} qovsM M
rn*'[i?
U0j>u*yE
qD>^aEd@4
mXyP;k
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 ;i6~iLY
\M\7k5$
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 klm>/MXI`
n
Ab~
做法如下: ?}s;,_GH
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 MBA?, |9Q#
5>f"
的信息,和一个结果集List: [%dsq`b#
java代码: tjXg
ktTP~7UVi
aHW34e@ebL
/*Created on 2005-6-13*/ \~,\|
package com.adt.bo; *%KIq/V
\Yr*x7!
import java.util.List; d%'#-w'
B0Wf$
s^7t
import org.flyware.util.page.Page; )f:i4.M
xNOKa*
/** Zc~7R`v7}
* @author Joa OU,FU@6,7w
*/ X<;.
publicclass Result { \]Ah=`
/)_4QSz7
private Page page; 08nh y[
,R`CAf%*
private List content; K& ^qn&
lUEbxN
/** St%x\[D
* The default constructor ^ul1{
*/ I8J>>H'#A
public Result(){ 3O$l;|SX
super(); ?; W"=I*3
} o[!o+M
.-rz30xT
/** \T_ZcV
* The constructor using fields Cb{D[
* m6e(Xk,)
* @param page :P_h_Tizv
* @param content 8+oc4~!A@n
*/ 7w)8s
public Result(Page page, List content){ Ljz)%y[s
this.page = page; 2T2<I/")O
this.content = content; G^)]FwTs
} a^J(TW/
]C,j80+pK
/** }VJ>}i*
* @return Returns the content. ,g7O
*/ hTLf$_|P
publicList getContent(){ yg}O9!M J
return content; z]8Mv(eL
} s|<n7 =J
Q;3`T7
/** fW2NYQP$:
* @return Returns the page. x!GDS>
*/ g3kbsi7_:
public Page getPage(){ Gpxp8[ {
return page; U!|)M
} lot`6]
@
,X/Wf
/** ZzE( S
* @param content O6y:e#0z
* The content to set. }XBF#BN
*/ Qt4mg?X/
public void setContent(List content){ qWr=Oiu
this.content = content; _)5E=
} 45.ks.
)b1hF
/** OoA!N-Q
* @param page t!rrYBSCr
* The page to set. -rcEG!
*/ E6~VHQa2?
publicvoid setPage(Page page){ }~@/r5Zl
this.page = page; Lf%3-P
} &{8:XJe*,%
} a%`Yz"<lQ
^x O](,H
Y[7prjd
H[KX xNYZ_
tP|/Q5s
2. 编写业务逻辑接口,并实现它(UserManager, Jp"29
)w
Z]b;%:>=
UserManagerImpl) 8+w*,Ry`
java代码: SV t~pE+Y
ASy?^Jrs5
(k!7`<k!Y
/*Created on 2005-7-15*/ tdRvg7v,N%
package com.adt.service; L3I$ K+c
%l&oRBC
import net.sf.hibernate.HibernateException; k5-4^
~|=D.}#$
import org.flyware.util.page.Page; xwD` R*
ir.RO7f
import com.adt.bo.Result; cL#-vW<s3
*RS/`a;,
/** Fya*[)HBo
* @author Joa }'wZ)N@
*/ $Be hU
publicinterface UserManager { c9 EtUv~
_$$.5?4
public Result listUser(Page page)throws }w4OCN\1
)=GPhC/sw
HibernateException; u=nd7:bv
K.QSt
} zl8M<z1`1
i=<;$+tW
cu>(;=
&'^.>TJ\
)@DDs(q=i
java代码: =!SV;^-q
1]''@oh{6U
-51LF=(!L
/*Created on 2005-7-15*/ 5T.U=_ag
package com.adt.service.impl; $>#0RzU
u4FD}nV
import java.util.List; 6ZE`'pk<
=At" Q6-O
import net.sf.hibernate.HibernateException;
RP{0+
)lLeL#]FLO
import org.flyware.util.page.Page; *CXc{{
import org.flyware.util.page.PageUtil; LGuZp?"
Y910\h@V
import com.adt.bo.Result; yH"i5L9
import com.adt.dao.UserDAO; Szt2 "AR
import com.adt.exception.ObjectNotFoundException; $$ *tK8#
import com.adt.service.UserManager; u_NLgM7*
&=)O:Jfa
/** q
n-f&R
* @author Joa X>`03?L
*/ C)j/!+nh
publicclass UserManagerImpl implements UserManager { I\_2=mL
$i+@vbU6
private UserDAO userDAO; dz+!yE\f$
RdD>&D$I
/** $)NS]wJ]3
* @param userDAO The userDAO to set. ~.3v\Q
*/ RN 4?]8
publicvoid setUserDAO(UserDAO userDAO){ s.7=!JQ#]p
this.userDAO = userDAO; %`k [xz
} AR( gI]1
j"6|$Ze8
/* (non-Javadoc) `PAQv+EYz
* @see com.adt.service.UserManager#listUser t<fah 3hl
[c=P)t7
V
(org.flyware.util.page.Page) :qxWANUa
*/ cdkEK
public Result listUser(Page page)throws 5FJLDT2Lg
yfV]f
LZ
HibernateException, ObjectNotFoundException { V/H+9+B7Im
int totalRecords = userDAO.getUserCount(); >m lQ@Z_O
if(totalRecords == 0) 'dBe,@
throw new ObjectNotFoundException
^cw9Yjh6
v|~=rvXFC
("userNotExist"); T1$p%yQH
page = PageUtil.createPage(page, totalRecords); Nzgi)xX0HX
List users = userDAO.getUserByPage(page); ?xv."I%
returnnew Result(page, users); uz+WVmb
} 2iM}YCV
O EaL2T
} 6oLOA}q
eb`3'&zV&)
&c!6e<o[p
vC>2%Zgf-
W7A!QS
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 O^CBa$
uQc("F
询,接下来编写UserDAO的代码: F-zIzzb&O
3. UserDAO 和 UserDAOImpl: h[qZM
java代码: ?7wcv$K5
-V;Y4,:c
ox`Zs2-a
/*Created on 2005-7-15*/ ppn 8
package com.adt.dao; <QvVPE}z
RuYIG?J=/
import java.util.List; }Fu1Y@M%
uMva5o
import org.flyware.util.page.Page; ]/Nt
7xO05)bz
import net.sf.hibernate.HibernateException; _+9i
PEEaNOk
1b
/** A z@@0
* @author Joa :|kO}NGM
*/ ]QR]#[Tn'
publicinterface UserDAO extends BaseDAO { QAx9W%
xP~GpVhLF
publicList getUserByName(String name)throws ds+K7B$
*~
I HVU
HibernateException; a]fFR~OY
?xUl_
publicint getUserCount()throws HibernateException; )t+pwh!8
U[3w9
publicList getUserByPage(Page page)throws =(hBgNH
mD7NQ2:wA
HibernateException; `AE6s.p?
\^,Jh|T
} >;Oa|G
r=3`Eb"t
iJhieNn
e eN`T&cI
7r?,wM
java代码: Y>aVnixx<
U/{t" e
sryA(V
/*Created on 2005-7-15*/ Xh}q/H<
package com.adt.dao.impl; USEmD5 q
{M:/HQo
import java.util.List; C ibfuR
} 'xGip@W
import org.flyware.util.page.Page; >WZ%Pv*
Pq<43:*?
import net.sf.hibernate.HibernateException; 9~j"6wS
import net.sf.hibernate.Query; i_m&qy<v
TJRp/BP
import com.adt.dao.UserDAO; M:OZWYQ
<-N eusx%
/** xib}E[-l#
* @author Joa JdI*@b2k[
*/ yn ofDGAf
public class UserDAOImpl extends BaseDAOHibernateImpl =%I[o=6
U%r{{Q1
implements UserDAO { 2X' H^t]7
)MI w/
/* (non-Javadoc) HLz<C
* @see com.adt.dao.UserDAO#getUserByName :T$}@& -
\mu';[gLd
(java.lang.String) vM5I2C3_>!
*/ p&Nav,9x
publicList getUserByName(String name)throws +&"W:Le:
&u|t{C#0
HibernateException { =.S2gO >
String querySentence = "FROM user in class 2u_=i$xW
4N=,9
com.adt.po.User WHERE user.name=:name"; wT+60X'
Query query = getSession().createQuery YhglL!pC
l2W+VBn6
(querySentence); }`
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query.setParameter("name", name); PT,*KYF_O"
return query.list(); zx"EAF{
} Bi fI.2|
D_<B^3w)
/* (non-Javadoc) JfJ ln[
* @see com.adt.dao.UserDAO#getUserCount() +1qvT_
*/ 'p[6K'Uq5
publicint getUserCount()throws HibernateException { P JKY$s.
int count = 0; *vBhd2HO
String querySentence = "SELECT count(*) FROM o|n;{zT"
J%ws-A?6rN
user in class com.adt.po.User"; Hh](n<Bs
Query query = getSession().createQuery kKbbsB
H4v%$R;K
(querySentence); W!8$:Ih_Z
count = ((Integer)query.iterate().next |U1u:=[
5C*Zb3VG4
()).intValue(); p({|=+bl
return count; NY?iuWa*g
} /Tl ybSC1
)N{PWSPs
/* (non-Javadoc) 8z=o.\@
* @see com.adt.dao.UserDAO#getUserByPage |#*+#27
4ybOK~z
(org.flyware.util.page.Page) HSG9|}$
*/ #F
.8x@
publicList getUserByPage(Page page)throws ~O./A-l
M[b~5L+S
HibernateException { (1{OQ0N+x
String querySentence = "FROM user in class A+Je?3/.
ocW`sE?EED
com.adt.po.User"; 9|>y[i
Query query = getSession().createQuery 3H"F~_H
p(4Ek"
(querySentence); ,t1s#*j\!q
query.setFirstResult(page.getBeginIndex()) 3S^Qo9S
.setMaxResults(page.getEveryPage()); YA8/TFu<_
return query.list(); Tz&cm=
} BI#(L={5
?b^<Tny
} `,GFiTPd
K24y;968
Q4ii25]*
IP !zg|c,
IMSm
至此,一个完整的分页程序完成。前台的只需要调用 QKz2ONV=)
Q(8W5Fb?
userManager.listUser(page)即可得到一个Page对象和结果集对象 c$A}mL_
e!i.u'z
的综合体,而传入的参数page对象则可以由前台传入,如果用 =|- xj h
F+xMXBD@>*
webwork,甚至可以直接在配置文件中指定。 bg4VHT7?>)
jAt65a
下面给出一个webwork调用示例: #2.C$
java代码: 5hCfi
mn<ea&
*LmzGF|
/*Created on 2005-6-17*/ U_B`SS
package com.adt.action.user; A^c5CJ_
; zy;M5l5.
import java.util.List; #@5 jOi
;NJM3g0I
import org.apache.commons.logging.Log; H~hAm
import org.apache.commons.logging.LogFactory; 1nLFtiki
import org.flyware.util.page.Page; f'Xz4;
^n]?!BdU
import com.adt.bo.Result; 78b9Sdi&
import com.adt.service.UserService; @qJv
import com.opensymphony.xwork.Action; d<;XQ.Wo7
iN`L* h
/** ER$~kFE2yP
* @author Joa kS7T'[d
*/ Y50$2%kM
publicclass ListUser implementsAction{ wVs |mG"
-gS/
privatestaticfinal Log logger = LogFactory.getLog ]}0+7Q
/ dn]`Ge)
(ListUser.class); R91u6r#
D3 E!jQ1
private UserService userService; 2gjA>ET`N
483vFLnF
private Page page; QaEXk5>e
KQqQ@D&n
privateList users; }S&SL)
L/cbq*L
/* %^E>~
* (non-Javadoc) F{<rIR
*
})w5`?Y
* @see com.opensymphony.xwork.Action#execute() a-DE-V Uls
*/ :Ws3+OI'm3
publicString execute()throwsException{ Nb{oH +$b
Result result = userService.listUser(page); qm}7w3I^
page = result.getPage(); 1-gX=8]]
users = result.getContent(); C{S6Ri
return SUCCESS; ln!KL'T]
} }mJ)gK5b 6
B "}GAk}V
/** I`KN8ll
* @return Returns the page. 9p$q@Bc
*/ 8@Km@o]?
public Page getPage(){ J5rR?[i{
return page; WCWBvw4&"{
} _H3cqD
]g+(#x_.?
/** AAl`bhx'n
* @return Returns the users. "ChBcxvxb:
*/ z?YGE iR/}
publicList getUsers(){ T
+4!g|Y
return users; Ip1QmP
} y.eBFf
;NPb
/** %r,2ZLZ
* @param page hQ8{
A7
* The page to set. >\p}UPx
*/ >zhbipA
publicvoid setPage(Page page){ "Ii!)n,
this.page = page; :3Jh f$
} kI;^V
WK^qYfq|
/** 1!NaOfP;@
* @param users dX3>j{_
* The users to set. p_(hM&>C
*/ 5Np. &
publicvoid setUsers(List users){ XZT( :(
this.users = users; Wl2>U(lj
} =gqZ^v&5U
?3, *
/** ffhD+-gTU
* @param userService nz&JG~Qfm
* The userService to set. J/*[wj
*/
^~ I
publicvoid setUserService(UserService userService){ +%~g$#tlJo
this.userService = userService; t-Fl"@s
} wIiT
:o
} V)Xcn'h
pV+;/y_
\5l}5<|
d16PY_
}R'oAE}$
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, yI;Qb7|^
U\z+{]<<
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 w/<hyEpxg
>y@w-,1he
么只需要: K&h|r`W(
java代码: 33C#iR1(WJ
lqs_7HhvRS
/4f;Niem
<?xml version="1.0"?> 8|/YxF<
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork Vqr&)i"b$
}A;Xd/,'r
1.0//EN" "http://www.opensymphony.com/xwork/xwork- w$!n8Aqs
&_6:TqJ
1.0.dtd"> mB~&nDU
lb('r"*.
<xwork> EIfrZg7R
:U>
oW97l
<package name="user" extends="webwork- XDGZqkt
]9:G3vq
interceptors"> '37b[~k4
:[&X*bw[
<!-- The default interceptor stack name /_|1,x-Kx
?~{xL"
--> hg~fFj3ST
<default-interceptor-ref Kna'5L5"
`xr%LsNn
name="myDefaultWebStack"/> +1%6-g4"
7$;$4.'
<action name="listUser" tQ67XAb
{mQJ6
G'ny
class="com.adt.action.user.ListUser"> #@fypCc
<param gr=`_k4~1
XTJ>y@
name="page.everyPage">10</param> vX\e*
v
<result GSH{1VS_b
>A/=eW/q
name="success">/user/user_list.jsp</result> (r4\dp&
</action> ;z>YwRV
on\\;V_/Q
</package> >R<fm
`dZ|}4[1
</xwork> %r"GL
9vu8koL
'3Ie0QO]"%
s$_#T
K36B9<F
g]#Wve
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 _;{-w%Vf
qg/5m;U
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。 gib]#n1!p
kR]SxG9
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 ^d*>P|n*@e
M)7enp) F.
V]}b3Y!(
Vvj]2V3
8rYK~Sz
我写的一个用于分页的类,用了泛型了,hoho %-Z~f~<?
w$4Lu"N:
java代码: O|~'-^
xJhbGK
`,Gk1~Wv
package com.intokr.util; [
UJj*n
)QD}R36Ic
import java.util.List; `9l\~t(M
$ Zr,-
/** ise}> A!t
* 用于分页的类<br> ,0bM*qob
* 可以用于传递查询的结果也可以用于传送查询的参数<br> MVdx5,t
* :N}KScS|Wa
* @version 0.01 eZi<C}z
* @author cheng (&,R1dLo
*/ b3lpNJ J
public class Paginator<E> { KoJG!Rm
privateint count = 0; // 总记录数 r
`dU
(T!
privateint p = 1; // 页编号 -huZnDN
privateint num = 20; // 每页的记录数 N}G(pq}
privateList<E> results = null; // 结果 *lAdS]I
/GUuu
/** `t&;Yk]-L
* 结果总数 C5UDez
*/ _4$DnQ6&
publicint getCount(){ (?y2@I}
return count; IcQ!A=lB
} x["
H@'
@xHv
publicvoid setCount(int count){ ;[ueNP%*y|
this.count = count; ?y)X $D^
} 9K<a}QJP
FOi`TZ8
/** ~*[4DQ[\
* 本结果所在的页码,从1开始 5FI>T=QF
* K3DJ"NJ<Ji
* @return Returns the pageNo. &NeYKh?
*/ 0pa^O$?p
publicint getP(){ +=Wdn)T
return p; ^ZUgDQduc
} ~+yo;[1Yc
wf%Ep#^6}
/** ZiYzsn
* if(p<=0) p=1 0\@|M @X=
* C/Bx_j((
* @param p ?
M_SNv
*/ ZS]f+}0/}
publicvoid setP(int p){ `r(J6,O
if(p <= 0) /ASI0h
p = 1; P'9io!Z-s
this.p = p; M) XQi/
} m?$G(E5
PSS/JFZ^
/** , vyx`wDd
* 每页记录数量 %W;Gf9.w
*/ 4ZpF1Zc4B
publicint getNum(){ 5O
;^Mk|
return num; z %E!tB2o
} C&N4<2b
g8A{aHb1}
/** !13
/+ u
* if(num<1) num=1 u#k,G`
*/ AiK4t-
publicvoid setNum(int num){ BrMp_M
if(num < 1) | V,jd
num = 1; ~j#6 goKn
this.num = num; 3MJWC o-[
} 9= $,] M
=3dbw8I
/** <|Eby!KXR
* 获得总页数 |S`yXsg
*/ 'xoE
[0!
publicint getPageNum(){ @k6}4O?{
return(count - 1) / num + 1; 9k[},MM
} @i-@mxk6<
DeQ'U!?+N
/** %&+R":Bw
* 获得本页的开始编号,为 (p-1)*num+1 .0W4Dp
*/ C+m^Z[
publicint getStart(){ )Q/`o,Vm
return(p - 1) * num + 1; EiP&Y,vT
} (A fbS=[
'4lT*KN7\
/** wf<`J/7u
* @return Returns the results. yPG\ &Bo
*/ )60f
publicList<E> getResults(){ ,h.Jfo54,
return results; yi-"hT`
} A<X :K
nl
j{Jc6U
public void setResults(List<E> results){ ZfCr"aL
this.results = results; gdFoTcHgO|
} <&EO=A
"|r^l
public String toString(){ s1 ^mk]
StringBuilder buff = new StringBuilder ! vVjZ
p2DNbY\]
(); as|c`4r\O
buff.append("{"); @j2*.ee
buff.append("count:").append(count); HT=Am
buff.append(",p:").append(p); Yn]yd1
buff.append(",nump:").append(num); P|P fG=
buff.append(",results:").append Iki+5
xc<eU`-'b
(results); 1S]gD&V
buff.append("}"); IH5} Az
return buff.toString(); '7LJuMp$#
} K-k.=6mS
],}afa!A
} wt=>{JM
E(3+o\w
&G|jzXE