Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 9=SZL~#CE
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 w <ID<
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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 k#.co~kS
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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 <3bh-)
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分页支持类: /dqKFxB1
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java代码: ec=C7M
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package com.javaeye.common.util; 'K1w.hC<
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import java.util.List; aE"t['
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publicclass PaginationSupport { -=RXhE_{
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publicfinalstaticint PAGESIZE = 30; BK{8\/dg
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privateint pageSize = PAGESIZE; bQ)r8[o!
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privateList items; Rq7ks To
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privateint totalCount; ZFzOW
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privateint[] indexes = newint[0]; Q3DxjD
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privateint startIndex = 0; 0KZ 3h|4lP
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public PaginationSupport(List items, int /sai}r1
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totalCount){ ,]d}pJ}PX`
setPageSize(PAGESIZE); DlP}Fp {
setTotalCount(totalCount); NF.SGga
setItems(items); 2{&" 3dq
setStartIndex(0); J4gIkZD
} >3bpa<M_
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public PaginationSupport(List items, int WC4Il
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totalCount, int startIndex){ >M!>Hl/
setPageSize(PAGESIZE); W1OGN4`C
setTotalCount(totalCount); %%_90t
setItems(items); [bp"U*!9P
setStartIndex(startIndex); 1.!(#I3
} k\lj<v<vD
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public PaginationSupport(List items, int +bXZE
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totalCount, int pageSize, int startIndex){ YPM>FDxDB
setPageSize(pageSize); U +]ab
setTotalCount(totalCount); |Mh;k6
setItems(items); \DHCf4,
setStartIndex(startIndex); <.<Nw6
} >GcFk&x
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publicList getItems(){ V7^?jck
return items; YMWy5 \
} h {m]n!
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publicvoid setItems(List items){ 2::T, Z
this.items = items; @iaN@`5I6s
} N>~*Jp2;
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publicint getPageSize(){ nuQ"\ G
return pageSize; KDhHp^IXQ
} =19]a
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publicvoid setPageSize(int pageSize){ d0xV<{,-
this.pageSize = pageSize; @@5u{K
} o{
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publicint getTotalCount(){ WULj@ds\~
return totalCount;
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} &a0%7ea`.S
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publicvoid setTotalCount(int totalCount){ Bj2rA.M
if(totalCount > 0){ ?{[H+hzz0
this.totalCount = totalCount; wO"Q{oi+
int count = totalCount / n`hSn41A
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pageSize; |gaZq!l
if(totalCount % pageSize > 0) zL|^5p`K
count++; )SQ g
indexes = newint[count]; E|6|m8
for(int i = 0; i < count; i++){ 81g&WQ'
indexes = pageSize * jm?mO9p~
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} Y~C S2%j
}else{ EKt-C_)U
this.totalCount = 0; eDm,8Se
} LgaJp_d>9*
} c:iMbJOn#
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publicint[] getIndexes(){ HP8pEo0Y
return indexes; }[Y):Yy
} X4TUi8ht!]
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publicvoid setIndexes(int[] indexes){ itvwmI,m\
this.indexes = indexes; rfZA21y{?
} F7hQNQu:
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publicint getStartIndex(){ sPw(+m*C
return startIndex; jlB3BwG{w
} ^KlOD_GN|
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publicvoid setStartIndex(int startIndex){ 9W8Dp?:
if(totalCount <= 0) 8}0
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this.startIndex = 0; "~
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elseif(startIndex >= totalCount) fG{oi(T
this.startIndex = indexes 07#!b~N
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[indexes.length - 1]; ,|H!b%ZW
elseif(startIndex < 0)
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this.startIndex = 0;
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else{ .3!4@l\9C
this.startIndex = indexes ^J G}|v3$
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[startIndex / pageSize]; (y36NH+
} V~wmGp.e
} %Xi%LUk{
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publicint getNextIndex(){ ooAZ,l=8
int nextIndex = getStartIndex() + ]+Vcu zq/
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pageSize; 3l^pY18H'
if(nextIndex >= totalCount) V]AL'}(
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return getStartIndex(); '*k\IM{h
else C+k>Ajr
return nextIndex; X*~YCF[_
} s6egd%r
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publicint getPreviousIndex(){ {\e}43^9N
int previousIndex = getStartIndex() - 5YCbFk^
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pageSize; qL#R
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if(previousIndex < 0) IF}r%%'Y$
return0; I,[EL{fz
else n >Ei1
return previousIndex; fP|\1Y?CS
} 26**tB<
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} N7_Co;#(zK
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抽象业务类 PEWzqZ|!;
java代码: $Yka\tS'
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/** wnX6XyUH
* Created on 2005-7-12 _e'mG'P(
*/ ^#o.WL%4/B
package com.javaeye.common.business; u *<
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import java.io.Serializable; QKO(8D 6+
import java.util.List; I%Awj(9BS
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import org.hibernate.Criteria; H,}?YW
import org.hibernate.HibernateException; wB^a1=C
import org.hibernate.Session; PjHm#a3zg%
import org.hibernate.criterion.DetachedCriteria; V*aTDU%-.
import org.hibernate.criterion.Projections; !8g
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import NO$Nl/XM
*.RVH<W=8
org.springframework.orm.hibernate3.HibernateCallback; UXP;'
import 2KEww3.{
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org.springframework.orm.hibernate3.support.HibernateDaoS OK 6}9Eu9
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upport; 0TpA3K
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import com.javaeye.common.util.PaginationSupport; ;W].j%]Le
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public abstract class AbstractManager extends NEk [0
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HibernateDaoSupport { Jj " {r{
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privateboolean cacheQueries = false; j66@E\dN
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privateString queryCacheRegion; zvD5i,I
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publicvoid setCacheQueries(boolean )sHPIxHI
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cacheQueries){ %vXQ Sz
this.cacheQueries = cacheQueries; K="+2]{I
} O^#u%/
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publicvoid setQueryCacheRegion(String Mx"tUoU6z
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queryCacheRegion){ yKJ^hv"#
this.queryCacheRegion = YLGLr@:q
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queryCacheRegion; EMG*8HRI>r
} GLyh1qNX
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publicvoid save(finalObject entity){ >y[S?M
getHibernateTemplate().save(entity); W=?87PkJu
} keOW{:^i
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publicvoid persist(finalObject entity){ ,whNh
getHibernateTemplate().save(entity); mxGN[%ve
} V*}zwms6
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publicvoid update(finalObject entity){
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getHibernateTemplate().update(entity); `t6L'%\
} H[
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publicvoid delete(finalObject entity){ @ni~ij
getHibernateTemplate().delete(entity); Ne
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}
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publicObject load(finalClass entity, 3)Y:c2
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finalSerializable id){
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return getHibernateTemplate().load Fev3CV$
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(entity, id); L ]c9
} S)yV51^B
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publicObject get(finalClass entity, mI#; pO2
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finalSerializable id){ ?C35
return getHibernateTemplate().get T*yveo&j
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(entity, id); <h9\ A&
} !$Z"\v'b
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publicList findAll(finalClass entity){ m{c#cR
return getHibernateTemplate().find("from -::%9D}P|
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" + entity.getName()); sfE8b/Z8
} HU9y{H
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publicList findByNamedQuery(finalString .Er/t"Qs;
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namedQuery){ 8
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return getHibernateTemplate VsEAo
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().findByNamedQuery(namedQuery); +_P
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} IviQ)hp
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publicList findByNamedQuery(finalString query, o[hP&9>q
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finalObject parameter){ (14kR
return getHibernateTemplate &tCtCk%{j
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().findByNamedQuery(query, parameter); g/p9"eBpq
} 9'g{<(R]
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publicList findByNamedQuery(finalString query, 3ohcHQ/a
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finalObject[] parameters){ E2'e}RQ
return getHibernateTemplate ZGhoV#T@
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().findByNamedQuery(query, parameters); WG} CPkj
} K- C-+RB
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publicList find(finalString query){ 389.&`Q%Ut
return getHibernateTemplate().find a] =\h'S
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(query); jSp&mD*xv
} +|)1_NK
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publicList find(finalString query, finalObject /? 1Yf
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parameter){ t<,p-TM]
return getHibernateTemplate().find g4a X
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(query, parameter); b.q"s6u
} A>%UYA
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public PaginationSupport findPageByCriteria '.
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(final DetachedCriteria detachedCriteria){ oV>AFs6
return findPageByCriteria zy6(S_j
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ^@L
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} I7z/GA\x
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public PaginationSupport findPageByCriteria cN}A rv
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(final DetachedCriteria detachedCriteria, finalint I@Z*Nu1L
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startIndex){ PJ'lZu8?x
return findPageByCriteria V,"iMo
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(detachedCriteria, PaginationSupport.PAGESIZE, 8pMZ~W;
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startIndex); y{Y+2}Dv/
} [Pwo,L,)
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public PaginationSupport findPageByCriteria Jo aDX ,
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(final DetachedCriteria detachedCriteria, finalint #IhLpO
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pageSize, ZHD0u)ri=J
finalint startIndex){
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return(PaginationSupport) 6Y_O^f
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getHibernateTemplate().execute(new HibernateCallback(){ |+xtFe
publicObject doInHibernate 6(^Upk=59
)):22}I#
(Session session)throws HibernateException { GHC?Tp
Criteria criteria = ^x"c0R^
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detachedCriteria.getExecutableCriteria(session); p/WH#4Xdr
int totalCount = &Dg)"Xji
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((Integer) criteria.setProjection(Projections.rowCount b}&7~4zw
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()).uniqueResult()).intValue(); 3^R] [;
criteria.setProjection tZu*Asx7
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(null); $K.%un Gm
List items = m7wc)"`t
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criteria.setFirstResult(startIndex).setMaxResults Fr3d#kVR
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(pageSize).list(); UG"6RW @
PaginationSupport ps = "ex~LB
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new PaginationSupport(items, totalCount, pageSize, R(?<97
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startIndex);
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return ps; iPY vePQ
} t>6x)2,TC
}, true); _{*$>1q
} @6YBK+"
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public List findAllByCriteria(final ~r>EF!U`h
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DetachedCriteria detachedCriteria){ ,;cel^.b
return(List) getHibernateTemplate }]g95xT
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().execute(new HibernateCallback(){ '6.>Wdd
publicObject doInHibernate 0qL
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(Session session)throws HibernateException { /,Dwu?Lcqp
Criteria criteria = ]o[X+;Tj|
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detachedCriteria.getExecutableCriteria(session); Q3Z%a|3W
return criteria.list(); ~ACP%QM=
} #7~tL23}]
}, true); I*:qGr+ WJ
} J|"nwY}a9
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public int getCountByCriteria(final pqH(
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DetachedCriteria detachedCriteria){ x7KcO0F{
Integer count = (Integer) E)80S.V
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getHibernateTemplate().execute(new HibernateCallback(){ 6R-C0_'h
publicObject doInHibernate t(j_eq}J
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(Session session)throws HibernateException { FYXw$7'l
Criteria criteria = T\2) $
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detachedCriteria.getExecutableCriteria(session); 3b|7[7}&
return o%Uu.P
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criteria.setProjection(Projections.rowCount N
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()).uniqueResult(); CQBT::
} $^vp'^uW>
}, true); `i t+D
return count.intValue(); 6^]`-4*W
} @Xq&t}*8
} "M9TB. O
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用户在web层构造查询条件detachedCriteria,和可选的 i>tW|N
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ERfd7V<c>
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PaginationSupport的实例ps。 C!ZI&cD9
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ps.getItems()得到已分页好的结果集 (XbMrPKG
ps.getIndexes()得到分页索引的数组 FylWbQU9
ps.getTotalCount()得到总结果数 hF7V !*5
ps.getStartIndex()当前分页索引 G}=`VYK
ps.getNextIndex()下一页索引 CdBthOPX)
ps.getPreviousIndex()上一页索引 Wj&<"Z6'm(
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 \#\`!L[1
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 TnN^2:cU
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一下代码重构了。 9,S,NvSq
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我把原本我的做法也提供出来供大家讨论吧: xHEVR!&c4
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首先,为了实现分页查询,我封装了一个Page类: 6-*~t8
java代码: eZ@Gu
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/*Created on 2005-4-14*/ vQ:x%=]
package org.flyware.util.page; 'v'`
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/** -d|BO[4j
* @author Joa 5wzQ?07T_
* F3r S6_
*/ W$z#ssr
publicclass Page { =gW"#ZjL){
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/** imply if the page has previous page */ #'J~Xk
privateboolean hasPrePage; Qy{NS.T
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/** imply if the page has next page */ sTd}cP
privateboolean hasNextPage; &q4ox7 1
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/** the number of every page */ 'fS?xDs-v
privateint everyPage; v\fzO#vj
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/** the total page number */ k k
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privateint totalPage; g/OI|1a
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/** the number of current page */ Z -pyFK\
privateint currentPage; Qe2m8
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/** the begin index of the records by the current c *.G]nRc
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query */ 5>'?:jY
privateint beginIndex;
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/** The default constructor */ VKT@2HjNT`
public Page(){ V)2"l"Kt
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} &\&'L|0F
3 sS=?q
/** construct the page by everyPage NV&;e[z
* @param everyPage U^B"|lc:[
* */ W=~id"XtJ
public Page(int everyPage){ "w;08TX8
this.everyPage = everyPage; B:e.gtM5
} vAi"$e
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/** The whole constructor */ Mx^y>\X)v
public Page(boolean hasPrePage, boolean hasNextPage, kXigX-
USE [N
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int everyPage, int totalPage, P\.WXe#j
int currentPage, int beginIndex){ .H
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this.hasPrePage = hasPrePage; ~@xT]D!BQ
this.hasNextPage = hasNextPage; S2Zx &D/_
this.everyPage = everyPage; !)NYW4"
this.totalPage = totalPage; 0xN!DvCg>.
this.currentPage = currentPage; (2:
N;
this.beginIndex = beginIndex; : @s8?eg
} +:}kZDl@ X
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/** ex.+'m<g
* @return &8Zeq3~
* Returns the beginIndex. T0g0jr{
*/ 1JIG+ZN md
publicint getBeginIndex(){ }|AX_=a
return beginIndex; L?C\Q^0"`G
} !syU]Yk
a/#+92C
/** NK 8<=
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* @param beginIndex 5$anqGw
* The beginIndex to set. $?-7OXj<
*/ HB%K|&!+
publicvoid setBeginIndex(int beginIndex){ 7@JjjV
this.beginIndex = beginIndex; vxb@9eb!H
} B
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/** wc"9A~
* @return u',b1 3g(
* Returns the currentPage. 5;}2[3}[
*/ M
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publicint getCurrentPage(){ Ys-^7
y_
return currentPage; -jFP7tEv
} `4_c0q)N4
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/** =`JW1dM
* @param currentPage cbfDB^_
* The currentPage to set. ;;M"hI3@
*/ ]7*kWc2
publicvoid setCurrentPage(int currentPage){ ;3mL^
this.currentPage = currentPage; Is
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} iZC>)&ax
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/** C(}^fJ6r
* @return JT}.F!q6E
* Returns the everyPage. xg?auje
*/ kj-=xhJ{=
publicint getEveryPage(){ Mw+v"l&mU
return everyPage; _FT6]I0
} >d#3|;RY
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/** 7"#f!.E
* @param everyPage a%v>eXc
* The everyPage to set. >[EBpYi
*/ >G&^?5
publicvoid setEveryPage(int everyPage){ ;ed#+$Na
this.everyPage = everyPage; w;~>k%}j
} J||E;=%f-Q
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/** v G2.]?
* @return Nfg{,/O
* Returns the hasNextPage. c+~LpSQ
*/ >:%BNeO
publicboolean getHasNextPage(){ #,TELzUVE
return hasNextPage; -;vT<G3
} )y`i@S}J
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/** ]W;:|/,c
* @param hasNextPage zz&vfO31J
* The hasNextPage to set. p3 e|j
*/ pcnl0o~
publicvoid setHasNextPage(boolean hasNextPage){ {tc57jsr
this.hasNextPage = hasNextPage; 0Q`&inwh
} PYu$1o9+N
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/** Ia#"/`||
* @return Od-Ax+Hp
* Returns the hasPrePage. ?,>5[Ha^?
*/ zSKKr?{
publicboolean getHasPrePage(){ @7%.7LK
return hasPrePage; bJwc1AJgH
} `0rRKlb j4
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/** $~G@
* @param hasPrePage ;
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* The hasPrePage to set. tvGlp)?.
*/ []gRfM]$&
publicvoid setHasPrePage(boolean hasPrePage){ 2QL?]Vo
this.hasPrePage = hasPrePage; \sITwPA[z
} dZDK7UL
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/** b)`pZiQP
* @return Returns the totalPage. >Mw'eQ0(y
* }vY.EEy!
*/ t!:)L+$3
publicint getTotalPage(){ o0l74
return totalPage; <aXoB*Y
} C `6S}f,
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/** Yz\
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* @param totalPage BPewc9RxV
* The totalPage to set. P$OUi!"
*/ xCq'[9oU
publicvoid setTotalPage(int totalPage){ $''UlWK
this.totalPage = totalPage; 1x{kl01m%
} _C$X04bU3V
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} bcn7,ht
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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 (hN?:q?'
#kci=2q_
个PageUtil,负责对Page对象进行构造: Ha218Hy0W
java代码: MMd.0JuaO
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/*Created on 2005-4-14*/ En\Z#0,V
package org.flyware.util.page; zN")elBi
jkt6/H
import org.apache.commons.logging.Log; P,ydt
import org.apache.commons.logging.LogFactory; ^V.'^=l
h/?6=D{
/** Mq'IkSt'
* @author Joa vxVOcO9<
* 9go))&`PJL
*/ CN\=9Rvs
publicclass PageUtil { yb?|Eww_o
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privatestaticfinal Log logger = LogFactory.getLog $8g42LR'
p9iu:MucD<
(PageUtil.class); V;;#/$oU:4
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/** w
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* Use the origin page to create a new page Ww`&i
* @param page SiTeB)/
* @param totalRecords 8R?I`M_b
* @return FM\[].
*/ :)4*^a/lC
publicstatic Page createPage(Page page, int ]0-<>
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totalRecords){
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return createPage(page.getEveryPage(), x<F$aXOS
iRve)
page.getCurrentPage(), totalRecords); ix*muVBj.
} tvpN/p
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/** "
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* the basic page utils not including exception 1-o V-K
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handler ArXl=s';s4
* @param everyPage t9` Ed>a
* @param currentPage Ct!S Tk[2
* @param totalRecords /b%Q[
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* @return page I`^Y Abnb
*/ }-nU3{1
publicstatic Page createPage(int everyPage, int H~Uq?!=b
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currentPage, int totalRecords){ A[JM4x
everyPage = getEveryPage(everyPage); {y-`QS
currentPage = getCurrentPage(currentPage); (p,}'I#i*
int beginIndex = getBeginIndex(everyPage, #pA[k-
#>[wD#XJV
currentPage); A3q*$.[
int totalPage = getTotalPage(everyPage, wS$46M<
-nR\,+N
totalRecords); 28UVDG1?
boolean hasNextPage = hasNextPage(currentPage, A*i_|]Q
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totalPage); *eGM7o*\X
boolean hasPrePage = hasPrePage(currentPage); 8x{Hg9
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returnnew Page(hasPrePage, hasNextPage, CDCC1B G"
everyPage, totalPage, :Q-F9o
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currentPage, ;_tO+xL&
,8##OB(
beginIndex);
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} %?=)!;[
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privatestaticint getEveryPage(int everyPage){ $E.XOpl&I
return everyPage == 0 ? 10 : everyPage; SFpQ#
} ~:Mm<*lL%
}N,>A-P
privatestaticint getCurrentPage(int currentPage){ e{!vNJ0`
return currentPage == 0 ? 1 : currentPage; H(> M
} Zi4d]
=DMbz`t
privatestaticint getBeginIndex(int everyPage, int 28oJFi]
UvBnf+,
currentPage){ ug&92Hdvy3
return(currentPage - 1) * everyPage; ny1 \4C
} fA^SD"xf
)`Ed_F}k
privatestaticint getTotalPage(int everyPage, int p+<}YDMb
K\^&+7&zVg
totalRecords){ t.U{Bu
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int totalPage = 0; 9,WG!4:+W
.$wLLE^*
if(totalRecords % everyPage == 0) /^4"Qv\@/
totalPage = totalRecords / everyPage; t?3BCm$Mi
else ?D=8{!R3
totalPage = totalRecords / everyPage + 1 ; gp/YjUH7k8
n(R_#,Hs
return totalPage; sFElD
]|
} m&Sp1=*Ejy
@q)E=G1<o0
privatestaticboolean hasPrePage(int currentPage){ JIV8q HC
return currentPage == 1 ? false : true; XKSX#cia
} q%S8\bt
xR}of"
privatestaticboolean hasNextPage(int currentPage, K)5;2lN,
N^J*!]|
int totalPage){ r/Dd&x
return currentPage == totalPage || totalPage == (}~ucI<~
x6e +7"#~
0 ? false : true; %U?)?iZdL
} oMc1:=EG
40.AM1Z0f
hdg<bZk:
} P)1EA;
HNMBXXf,B
>{XScxaB`
!Uy>eji}
e1^l.>2d6
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 uV77E*+7\
+c?ie4
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 7K :FeW'N
-tyaE
做法如下: r*Z_+a8
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ? s4oDi|:
<Uwwux<v
的信息,和一个结果集List: ]!aUT&
java代码: ImHU:iR[J-
r|-J8s#
^ItAW$T]F
/*Created on 2005-6-13*/ hr~.Lj5^W
package com.adt.bo; +WLD
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import java.util.List; b1)\Zi
})7K S?
import org.flyware.util.page.Page; /7vE>mSY
0WXVc
/** **HrWM%?8o
* @author Joa !NA`g7'
*/ 6t$N78U
publicclass Result { uO"8aD`W
5!h<b3u>]
private Page page;
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U8[Qw}T P
private List content; G?ZC9w]rA
mATH*[Y
/** 5rN7':(H!%
* The default constructor Gh+f1)\FA"
*/ r?$&Z^
public Result(){ acae=c|X
super(); }.t^D|
} ^O \q3HA_4
:D4];d>1
/** 5M.Red.L
* The constructor using fields D aDUK?
* O!
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* @param page JZw^W{
* @param content Da CblX
*/ [yF^IlSs
public Result(Page page, List content){ g]4yAV<2
this.page = page; M:(&n@e
this.content = content; )f[C[Rd
}
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;-Ado8
/** `u=oeM:
* @return Returns the content. 5"uNj<.V
*/ y($EK(cb
publicList getContent(){ 3P`WPph
return content; f}blB?e
} wt\m+!u`
tNB%eb{
/** Y{j7Q4{
* @return Returns the page. <(?'
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*/ oN ;-M-(
public Page getPage(){ pU@YiwP"]x
return page; IywiCMjH
} V8T#NJ
S*s:4uf
/** J@gm@ jLc
* @param content K4Y'B
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* The content to set. $E @ouX?
*/ jJ<;2e~OW
public void setContent(List content){ (gDQ\t@3-
this.content = content; ;t~*F#p(!
}
[9J:bD
$':JI#
/** sX!3_'-
* @param page Wt"ww~h`(
* The page to set. }pKv.
*/ Q!`)e @r
publicvoid setPage(Page page){ iel-<(~
this.page = page; 6N?#b66
} 1y~L8!:L
} zF?31\GOX
gY%OhYtF2
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V07VwVD
@ "0uM?_)-
2. 编写业务逻辑接口,并实现它(UserManager, #)FDl70S8
.Nk}Z9L]k
UserManagerImpl) J ZA*{n2
java代码: R qnWtE
%6N)G!P
[0wP\{%
/*Created on 2005-7-15*/ dDo6fP2
package com.adt.service; i`R(7Z
m^'~&!ba
import net.sf.hibernate.HibernateException; :q(D(mK
B_!wutV@
import org.flyware.util.page.Page; 'OG{*TDPu
JBvk)ogM
import com.adt.bo.Result; &jt02+Hj'
x
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/** 3`xsK[
* @author Joa jmSt?M0.xV
*/ z+ uL "PG[
publicinterface UserManager { }'PG!+=I
]W+)ee|D
public Result listUser(Page page)throws & \JLTw
MCM/=M'y
HibernateException; O/(3 87= U
k{_1r;
} ^u3*hl}YKy
Bpm,mp4g\#
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>CH
"oHp.$+K
java代码: xm^N8
k]t,q$Vd
&<`-:x1 2_
/*Created on 2005-7-15*/ b By'v/
package com.adt.service.impl; Ywmyr[Uh'
JaA&eT|
import java.util.List; `(P
"u
W8< @sq~I
import net.sf.hibernate.HibernateException; EG%I1F%
mZ]P[lQ'5
import org.flyware.util.page.Page; ?n2C
import org.flyware.util.page.PageUtil; *3!(*F@M,
dr.**fGYde
import com.adt.bo.Result; (Z5qf
import com.adt.dao.UserDAO; MST:.x ;
import com.adt.exception.ObjectNotFoundException; h|K\z{ A
import com.adt.service.UserManager; vz- 9<w;>a
yq1Gqbh
l
/** qI(W$
* @author Joa *+NGi(N
*/ aXQ&@BZ{j
publicclass UserManagerImpl implements UserManager { AbL5 !'
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private UserDAO userDAO; 7F"3 <U@J
3(MoXA*
/** >ze>Xr'm5=
* @param userDAO The userDAO to set. BHEs+e0
*/ xT:qe
publicvoid setUserDAO(UserDAO userDAO){ ;&RUE
this.userDAO = userDAO; pi|\0lH6W
} iK ohuZr
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/* (non-Javadoc) b*cW<vX}~
* @see com.adt.service.UserManager#listUser :b.3CL\.6
a:=q8Qy
(org.flyware.util.page.Page) Ti hnSb
*/ |Uc<;> l
public Result listUser(Page page)throws X";TZk
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HibernateException, ObjectNotFoundException { joxS+P5#
int totalRecords = userDAO.getUserCount(); Tnf&pu#5
if(totalRecords == 0) th5
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throw new ObjectNotFoundException C_6GOpl
cR,'o'V/
("userNotExist"); 65'`uuPx
page = PageUtil.createPage(page, totalRecords); Qk?jGXB>^
List users = userDAO.getUserByPage(page); ^!q 08`0
returnnew Result(page, users); eVJ= .?r
} NKRaQr
c'"#q)
} ,jAx%]@,I
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R
4 DM_u
XPar_8I
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 d^ 2u}^kG
X7t5b7
询,接下来编写UserDAO的代码: TFAYVK~
3. UserDAO 和 UserDAOImpl: ~D<7W4c
java代码: E%-Pyg*
3yeK@>C
R1II k
/*Created on 2005-7-15*/ &r&;<Q
package com.adt.dao; V*~1,6N[
v]B0!k&4.
import java.util.List; jVLY!7Z4
`6|i&w:b
import org.flyware.util.page.Page; |E46vup
]ev *m&O
import net.sf.hibernate.HibernateException; D-'i G%)kA
ev~dsk6k
/** 6\; 4
4,3
* @author Joa ;M%oQ>].[
*/ u)<Ysx8G
publicinterface UserDAO extends BaseDAO { l0qdk#v
pYYqGv^oa
publicList getUserByName(String name)throws kqj;l\N
<8}KEe4
HibernateException; k)?,xY\AV
&?P=arU
publicint getUserCount()throws HibernateException; bRx2
c
?| D$#{^
publicList getUserByPage(Page page)throws LEYWH%y
`'z(--J}`
HibernateException; :iP>z}h
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} >t1_5
QH@Q\
@,
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o?:;8]sr!
;X?Ah
java代码: TYs+XJ'Xj
]jHh7> D
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/*Created on 2005-7-15*/ y#hga5
package com.adt.dao.impl; <;2P._oZ
8QkWgd7y
import java.util.List; kvMk:.
?b!CV
import org.flyware.util.page.Page;
`_NnQ%
*(?U
import net.sf.hibernate.HibernateException; :z0s*,QH
import net.sf.hibernate.Query; LydbP17K}
ek<PISlci
import com.adt.dao.UserDAO; D6&mf2'u
pFpQ\xc9$
/** kx"hWG4
* @author Joa "#mXsp-ut
*/ *u|lmALs
public class UserDAOImpl extends BaseDAOHibernateImpl >P6^k!R1y
/'8*aUa
implements UserDAO { Sqp;/&Ji
Q3<bC6$r
/* (non-Javadoc) ,!o\),N
* @see com.adt.dao.UserDAO#getUserByName XM$5S+e
m#5|J@]
(java.lang.String) sDLVYD
*/ <7_ |Q
publicList getUserByName(String name)throws 1g~Dm}m
m.\ >95!
HibernateException { { ()p%#*
String querySentence = "FROM user in class t,--V|7-
jMm_A#V>p
com.adt.po.User WHERE user.name=:name"; N<#S3B?.
Query query = getSession().createQuery 2*~JMbm
oj,HJH+
(querySentence); 9[epr+f
query.setParameter("name", name); Jcwh|w9D8
return query.list(); Zu2m%=J`
} 9IS1.3
l _kg3e4
/* (non-Javadoc) u4b3bH9U
* @see com.adt.dao.UserDAO#getUserCount() "e1{V8
4
*/ hj^G}4
publicint getUserCount()throws HibernateException { E5,%J
int count = 0; s)=!2A Y
String querySentence = "SELECT count(*) FROM -Z`( ?
k
6=Y3(#Ddt
user in class com.adt.po.User"; c]AKeq]
Query query = getSession().createQuery mhHA!:Y
8!
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(querySentence); EmtDrx4!(f
count = ((Integer)query.iterate().next U~u6}s]:
dCf'\@<<
()).intValue(); Bo](n*i
return count; p0}+071o%
} >cwJl@wx-
<r_P?
lZW
/* (non-Javadoc) vh1
Ma<cx
* @see com.adt.dao.UserDAO#getUserByPage p^pQZ6-
"VT{1(]t
(org.flyware.util.page.Page) OCbQB5k3
*/ Vze!/ED
publicList getUserByPage(Page page)throws TnvHO_P,
kbIY%\QSO
HibernateException { JEK%yMj
String querySentence = "FROM user in class F"B<R~
Sah<sb=
com.adt.po.User"; 6i9Q,4~
Query query = getSession().createQuery 0UM@L
}L
K^z5x#Yj
(querySentence); Y0P}KPD
query.setFirstResult(page.getBeginIndex()) bl:a&<F
.setMaxResults(page.getEveryPage()); ZXssvjWQV}
return query.list(); 4*N@=v
} [3{:H"t
dUsJv
} sUyCAKebRr
2-"Lxe65f
3oppV_^JdT
/ctaAQDUh\
s]nGpA[!
至此,一个完整的分页程序完成。前台的只需要调用 C;58z5*,
<eud#v
userManager.listUser(page)即可得到一个Page对象和结果集对象 2g ?Jb5)
=FtM;(\
的综合体,而传入的参数page对象则可以由前台传入,如果用 F- !}dzO
*7xQp!w^
webwork,甚至可以直接在配置文件中指定。 +YQ)}v
fw(j6:p
下面给出一个webwork调用示例: MYDf`0{$_a
java代码: (x1"uy7_
k$$S!qi#
0]:*v?
/*Created on 2005-6-17*/ J-eA,9J
package com.adt.action.user; 9:CVN@E
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import java.util.List; 3%vx'1h[
?vht~5'
import org.apache.commons.logging.Log; ?j&~vy= T
import org.apache.commons.logging.LogFactory; 1eE]4Z4Q
import org.flyware.util.page.Page; JhMrm%
|(J
?#?
import com.adt.bo.Result; $.r}g\43P
import com.adt.service.UserService; X_0{*!v8
import com.opensymphony.xwork.Action; oSu|Yn
y7;XOPm
/** AXNszS%4
* @author Joa O9qKwn;q(
*/ By"^ Z`EP4
publicclass ListUser implementsAction{ }Yo15BN+
W{$+mow7S
privatestaticfinal Log logger = LogFactory.getLog '$kS]U
tvj'{W
(ListUser.class); hZss
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private UserService userService; [kp7LA"`
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private Page page; HAI1%F236
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privateList users; JX2
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/* "b1R5(Ar
* (non-Javadoc) K;ry4/Vap
* ^;bGP.!p
* @see com.opensymphony.xwork.Action#execute() 35@Ibe~
*/ e%@[d<Ta\
publicString execute()throwsException{
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Result result = userService.listUser(page); P5
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page = result.getPage(); wNf*/?N
users = result.getContent(); g`~lIt[=
return SUCCESS; t;e]L'z@:
} of[|b{Ze4~
yN WbI0a
/** W"}*Q-8W
* @return Returns the page. 6M<mOhp@}n
*/ N8L)KgM5#7
public Page getPage(){ V"2AN3~&
return page; H,4,~lv|
} g*w-"%"O
<-oRhi4
/** }07<(,0n
* @return Returns the users. !g8.8(/t)
*/ d'g{K]=tF
publicList getUsers(){ *{;A\sL
return users; @h7GTA \
} ]uj.uWD
Tm~#wL
+r
/** v-r[~
* @param page !Pi?
!
* The page to set. L/ICFa.G
*/ {L2Gb(YLW
publicvoid setPage(Page page){ vS*0CR\
this.page = page; 8w@W8(3B
} u7y7
nE"b`
/** .}hZ7>4-
* @param users lA^Kh
* The users to set. Kj<<&_B.H
*/ n'ca*E(
publicvoid setUsers(List users){ ->"h5h
this.users = users; gU 2c--`
} d8 BK/b
f@.Q%+!4
/** 6'sFmC
* @param userService x_H7=\pX]
* The userService to set. PEQvEruZ}
*/ nO.+&kA
publicvoid setUserService(UserService userService){ tgF(=a]o
this.userService = userService; @Ozf}}#
} yV]-Oa$*s0
} zC>(!fJqq
S,<.!v 57
CK`3
Kp=3\) &
;|$]Qq
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, kq.R(z+
F0ivL`
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 ks`
CR<pB)F?a
么只需要: |s3HeY+Co
java代码: U+}9X^
sxQ ,x/O
7!yF5+_d
<?xml version="1.0"?> W 9:{pQG
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork my\oC^/9
Ef*.}gcU
1.0//EN" "http://www.opensymphony.com/xwork/xwork- sFz4^Kn
N n-6/]d#
1.0.dtd"> mBgx17K/-_
Y X{
<xwork> [Oy2&C
PM?Ri^55<L
<package name="user" extends="webwork- KZ
>"L
tIy/QN_42
interceptors"> 2mp>Mn~K^
E~O>m8hF
<!-- The default interceptor stack name )I
UWM
.N><yQ-j3'
--> ^fiRRFr[
<default-interceptor-ref md
+`#-D\O
czsoD)N
name="myDefaultWebStack"/> SFPIr0 u
;@-5lCvC(+
<action name="listUser"
! +VN
!J?=nSu
class="com.adt.action.user.ListUser"> OsSiBb,W79
<param >`V|`Zi ?
AkQFb2|ir
name="page.everyPage">10</param> ?}Ptb&Vk(
<result o?hw2-mH
VKfHN_m*
name="success">/user/user_list.jsp</result> /ykxVCvAt
</action> {kO:HhUg
J2k'Ke97o
</package> <W|{)U?p
kX .1#%Ex
</xwork> b6$A@b
9oN'.H^
)PNH| h
8uD%]k=#!
<^c0bY1
nk,Mo5iqV
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 T`<k4ur
`e;Sjf<
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。 ZTz(NS
EK
x3F L/^S
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 LK}eU,m=
/%'7sx[p
gY^TBR0?m
(S 3kP5:F
\yizIo.Y`
我写的一个用于分页的类,用了泛型了,hoho N<r0I-
X10TZ
java代码: <