Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 1ux~dP
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 R X:wt
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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 |\"vHt?@G
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 `W< 7.
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分页支持类: "I?sz)pxG
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java代码: ]8KAat~J
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package com.javaeye.common.util; oomB/"Z
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import java.util.List; X9C)FS
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publicclass PaginationSupport { | iEhe
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publicfinalstaticint PAGESIZE = 30; Bt4
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privateint pageSize = PAGESIZE; [?VYxX@
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privateList items; FLdO
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privateint totalCount; L8n1p5gx3
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privateint[] indexes = newint[0]; 7q?u`3l
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privateint startIndex = 0; vUl5%r2O4
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public PaginationSupport(List items, int |4//%Ll/
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totalCount){ 4Z>hP]7
setPageSize(PAGESIZE); Z)Y--`*
setTotalCount(totalCount); *F/ uAI^)
setItems(items); B
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setStartIndex(0); 0:UK)t)3I
} =0 W`tx
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public PaginationSupport(List items, int rBLkowDP*
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totalCount, int startIndex){ f)hs>F
setPageSize(PAGESIZE); (v(!l=3
setTotalCount(totalCount); gv$6\1
setItems(items); V_jVVy30Ji
setStartIndex(startIndex); aCzdYv\} &
} ""l_&3oz
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public PaginationSupport(List items, int xMJF1O?3
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totalCount, int pageSize, int startIndex){ Dgh|,LqUB
setPageSize(pageSize); 6J0HaL
setTotalCount(totalCount); u38FY@U$
setItems(items); JmdXh/X
setStartIndex(startIndex); rhY>aj
} .b>1u3
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publicList getItems(){ <(W0N|1v
return items; yyZH1A
} ,!_
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publicvoid setItems(List items){ 49n.Gc
this.items = items; V3baEy>=z
} (.\GI D+i
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publicint getPageSize(){ wJ-G7V,)
return pageSize; 9], ;i7c
} 3;=nQ{0b
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publicvoid setPageSize(int pageSize){ 0L10GJ "(
this.pageSize = pageSize; [o8a(oC
} 1\1a;Q3W%,
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publicint getTotalCount(){ fU^B
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return totalCount; ^c{}G<U^
} O-B~~$g
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publicvoid setTotalCount(int totalCount){ ,GEMc a,`
if(totalCount > 0){ j-|YE?AA
this.totalCount = totalCount; GXB4&Q!C
int count = totalCount / R L/~E
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pageSize; Y W_E,A>h
if(totalCount % pageSize > 0) <$Q\vCR
count++; M>J8J*
indexes = newint[count]; Ge$cV}
for(int i = 0; i < count; i++){ ;AKtbS;H
indexes = pageSize * B[7|]"L@
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i; *FDz20S
} QxvxeK!Y
}else{ ut%t`Y(
]
this.totalCount = 0; t ]{qizfOB
} =Run
} zMb7a_W
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publicint[] getIndexes(){ U~Aw=h5SD
return indexes; ^zkTV_,cRp
} Rt~Aud[
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publicvoid setIndexes(int[] indexes){ Nk=F.fp|/
this.indexes = indexes; quk~z};R>\
} ^qqP):0y1V
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publicint getStartIndex(){ HRi~TZ?\
return startIndex; $+Ke$fq.>
} 0$l=ME(
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publicvoid setStartIndex(int startIndex){ 6u/3"A]'
if(totalCount <= 0) x^_Wfkch]
this.startIndex = 0; kH*l83
elseif(startIndex >= totalCount) V[,/Hw~d%
this.startIndex = indexes WpC@nz?
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[indexes.length - 1]; 0K7]<\)
elseif(startIndex < 0) pVn6>\xa
this.startIndex = 0; f]"][!e!,
else{ oQ~Q?o]Ri
this.startIndex = indexes ,R0@`t1 p
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[startIndex / pageSize]; m
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} Q_/{TE/sO5
} A=|LMJMWR
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publicint getNextIndex(){ #/sKb2eQ
int nextIndex = getStartIndex() + *{tn/ro6a
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pageSize; DCX4!,ZF
if(nextIndex >= totalCount) h*)spwF-
return getStartIndex(); ?
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else mU:C{<Z
return nextIndex; tp$NT.z
} >#dNXH]9
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publicint getPreviousIndex(){ 5b9_6L6
int previousIndex = getStartIndex() - ,0[8/)$M
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pageSize; is{I5IR\/
if(previousIndex < 0) Gh0H)
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return0; +xRja(d6
else 3O%[k<S\VO
return previousIndex; liFNJd`|o+
} : Ey
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} =sedkrM
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抽象业务类 gqNd@tYI
java代码: )vOZp&
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/** oe`oUnN
* Created on 2005-7-12 T2Cdw\
*/ '1ff| c!x9
package com.javaeye.common.business; h0Acpd2
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import java.io.Serializable; 5ejdf
import java.util.List; *gHOH!K,S
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import org.hibernate.Criteria; ~FH''}3:3
import org.hibernate.HibernateException; X55Eemg/
import org.hibernate.Session; `j[)iok
import org.hibernate.criterion.DetachedCriteria; v"O{5LM"
import org.hibernate.criterion.Projections; dGQxGt1
import 8^p/?R^bu
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org.springframework.orm.hibernate3.HibernateCallback; eznw05U
import 8U\;N
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org.springframework.orm.hibernate3.support.HibernateDaoS xBG&ZM4"^f
/#9O{)
upport; HoymGU`w
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import com.javaeye.common.util.PaginationSupport; ?A(=%c|,g
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public abstract class AbstractManager extends wGd8q xa
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HibernateDaoSupport { u)&6;A4
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privateboolean cacheQueries = false; a~OCo
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privateString queryCacheRegion; P^v`5v
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publicvoid setCacheQueries(boolean !fwLC"QC
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cacheQueries){ 6 )0$UW
this.cacheQueries = cacheQueries; &k&tkE
} "<3PyW?zt
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publicvoid setQueryCacheRegion(String y2\, L
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queryCacheRegion){ gO<>L0,j
this.queryCacheRegion = 6aCAz2/
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queryCacheRegion; {#=q[jVi%1
} %whPTc0P
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publicvoid save(finalObject entity){ ub}t3#
getHibernateTemplate().save(entity); ^ft_1 d[
} V. 'EP
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publicvoid persist(finalObject entity){ $"J+3mO
getHibernateTemplate().save(entity); fcr\XCG7U
} fbNVmjb$)
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publicvoid update(finalObject entity){ Da_g3z
getHibernateTemplate().update(entity); 0%k`*8
} ..'^1IOA
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publicvoid delete(finalObject entity){ jFw?Ky2
getHibernateTemplate().delete(entity); M,e_=aq
} >8 t3a-/
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publicObject load(finalClass entity, pb$U~TvzhM
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finalSerializable id){ `P)atQ
return getHibernateTemplate().load B Gh%3"q
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(entity, id); ocAoqjlT[
} d
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publicObject get(finalClass entity, YX18!OhQ
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finalSerializable id){ /0!6;PC<
return getHibernateTemplate().get Jmf&&)p
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(entity, id); [#)-F_S
} |6"zIHvtc
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publicList findAll(finalClass entity){ MJ8z"SKnV
return getHibernateTemplate().find("from wR@fB
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" + entity.getName()); 477jS6 ^e&
} tE9%;8;H
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publicList findByNamedQuery(finalString JDD(e_dw
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namedQuery){ opjrU$<]N
return getHibernateTemplate NL0X =i
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().findByNamedQuery(namedQuery); )<1M'2
} ]5YG*sD4
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publicList findByNamedQuery(finalString query, 3vHEPm]
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finalObject parameter){ J ;i/X;^
return getHibernateTemplate `+\+
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().findByNamedQuery(query, parameter); 9-Qub+0o
} K
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publicList findByNamedQuery(finalString query, EbY%:jR
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finalObject[] parameters){ "DjD"?/b
return getHibernateTemplate }PK8[N
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().findByNamedQuery(query, parameters); ;I:jd")
} v /G,
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publicList find(finalString query){ G3OqRH
return getHibernateTemplate().find 7 H.2]X
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(query); Hp8)-eT
} SE;Jl[PgcL
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publicList find(finalString query, finalObject kZ[E493bV
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parameter){ )<UNiC
return getHibernateTemplate().find c9= ;:E
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(query, parameter); e#0R9+"Ba
} /$%apci8
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public PaginationSupport findPageByCriteria 3!Gnc0%c
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(final DetachedCriteria detachedCriteria){ Z'/:
return findPageByCriteria ]Yp;8#:1
`CUTb*{`
(detachedCriteria, PaginationSupport.PAGESIZE, 0); }RO Cj,|
} [_^K}\/+
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public PaginationSupport findPageByCriteria &+xNR2";
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(final DetachedCriteria detachedCriteria, finalint |/Ggsfmby
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startIndex){ * A@~!@XE4
return findPageByCriteria /Pxt f~$
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(detachedCriteria, PaginationSupport.PAGESIZE, bsmZR(EnU
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startIndex); }~:`9PV)Z%
} ) 'j7Ra
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public PaginationSupport findPageByCriteria 2h@/Q)z
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(final DetachedCriteria detachedCriteria, finalint Z0`Bn5
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pageSize, O8wR#(/
finalint startIndex){ V) a<)
return(PaginationSupport) :tl*>d~
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getHibernateTemplate().execute(new HibernateCallback(){ [GyW1-p33w
publicObject doInHibernate YiTiJ9jf
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(Session session)throws HibernateException { T[`o$j6
Criteria criteria = "@xI
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detachedCriteria.getExecutableCriteria(session); r,cV(
int totalCount = 2TXrVaM
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((Integer) criteria.setProjection(Projections.rowCount +4Aj/$%[q
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()).uniqueResult()).intValue(); *Ew`Fm H
criteria.setProjection (oBvpFP33
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(null); bE74Ui
List items = 8doKB<#_+=
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criteria.setFirstResult(startIndex).setMaxResults bX Q*d_]WT
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(pageSize).list(); }R=n!Y$F
PaginationSupport ps = c$Z3P%aP'V
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new PaginationSupport(items, totalCount, pageSize, fa//~$#"{L
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startIndex); l~b# Y&
return ps; ?NOc]'<(G
} -|bnvPmE
}, true); M4w,J2_8MK
} F{WV}o=MY
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public List findAllByCriteria(final }^+E S^~
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DetachedCriteria detachedCriteria){ w
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return(List) getHibernateTemplate !nQ_<
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().execute(new HibernateCallback(){ mEeD[dMN
publicObject doInHibernate 3k(A&]~v
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(Session session)throws HibernateException { *'H0%GM
Criteria criteria = &b'IYoe
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detachedCriteria.getExecutableCriteria(session); 97l<9^$
return criteria.list(); Gf_Je
} ?41bZ$j
}, true); #Z#rOh
} C jISU$O
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public int getCountByCriteria(final .)59*'0
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DetachedCriteria detachedCriteria){ 'i+j;.
Integer count = (Integer) \NU^Jc_k7
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getHibernateTemplate().execute(new HibernateCallback(){ )l g>'O
publicObject doInHibernate +txFdc
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(Session session)throws HibernateException { O$zXDxn
Criteria criteria = QiC}hj$
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detachedCriteria.getExecutableCriteria(session); iga.B
return ~ES6Qw`Oe
$$F iCMI
criteria.setProjection(Projections.rowCount e0;0 X7
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()).uniqueResult(); ;O8'vp
} O/Cwm;&t
}, true); |`eHUtjH
return count.intValue(); zW#P
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} ZZq]I
} VJbsM1y M
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用户在web层构造查询条件detachedCriteria,和可选的 X!,huB^i
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 3Gi^TXE]
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PaginationSupport的实例ps。 )hG4,0hv&
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ps.getItems()得到已分页好的结果集 2(I S*idq
ps.getIndexes()得到分页索引的数组 wtM1gYl^
ps.getTotalCount()得到总结果数 3qf?n5"8
ps.getStartIndex()当前分页索引 41uiW,
ps.getNextIndex()下一页索引 K}|zKTh:?
ps.getPreviousIndex()上一页索引 ES,T[
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 V#X#rDfJZ
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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 w1Txz4JqB
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一下代码重构了。 #ZkT![`
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我把原本我的做法也提供出来供大家讨论吧: 9]C%2!Ur,
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首先,为了实现分页查询,我封装了一个Page类: "w&IO}j;=
java代码: Oh# z zo
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/*Created on 2005-4-14*/ &cGa~#-u
package org.flyware.util.page; |PtfG2Ty?
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/** 9Js+*,t
* @author Joa )E|{.K
* H2lQ(Y+H
*/ ;
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publicclass Page { ^'\JI
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/** imply if the page has previous page */ <*Nd%Ca
privateboolean hasPrePage; R_^0Un([
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/** imply if the page has next page */ %u}#|+8}
privateboolean hasNextPage; -*A1[Z ?
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/** the number of every page */ 4mjlat(d
privateint everyPage; v}LI-~M>U
:
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/** the total page number */ qCkC 2Fy(
privateint totalPage; v]Fw~Y7l!
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/** the number of current page */ >{S
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privateint currentPage; A!cY!aQ
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/** the begin index of the records by the current xv"v='
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query */ NX4G;+6
privateint beginIndex; c=,HLHpFO(
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/** The default constructor */ {p.^E5&
public Page(){ &@K6;T
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} 1etT."
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d
/** construct the page by everyPage ZIN1y;dJ
* @param everyPage nll=Vd[
* */ i50E#+E8
public Page(int everyPage){ en>n\;U
this.everyPage = everyPage; > ^=n|%
} ~R&rQJJeJ
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/** The whole constructor */ x<h|$$4S
public Page(boolean hasPrePage, boolean hasNextPage, '_b3m2I.G
R_D&"&
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int everyPage, int totalPage, $DXO7;#
int currentPage, int beginIndex){ 5tyA{&Ao
this.hasPrePage = hasPrePage; $K.DLqDt
this.hasNextPage = hasNextPage; ZC]|s[
this.everyPage = everyPage; NH;e|8
this.totalPage = totalPage; f&j\gYWq
this.currentPage = currentPage; A9lw^.
this.beginIndex = beginIndex; eC"k-a8j+
} up{0ehr
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/** (gnN</%
* @return Atb`Q'Yrw
* Returns the beginIndex. K@<*m!%<2
*/ qfG:vTm
publicint getBeginIndex(){ Nw9@E R
return beginIndex; | }L=e.
} L3w.<h
JH| D
/** tnAj3wc
* @param beginIndex i=L 86Ks
* The beginIndex to set. {yv_Ni*6!
*/ A_l\ij$Y
publicvoid setBeginIndex(int beginIndex){ ny{S&f
this.beginIndex = beginIndex; WMHYOJR
} Nyt*mbd5
{
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/** [;yKbw!C
* @return {+zG.1o^
* Returns the currentPage. V:#rY5X
*/ gg.]\#3g
publicint getCurrentPage(){ &#JYh=#
return currentPage; 118lb]
} mKjTJzS
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/** whYk"N
* @param currentPage wK0x\V6dJ
* The currentPage to set. (kVY\!UAt
*/ ]isq}Qv~
publicvoid setCurrentPage(int currentPage){ >|, <9z`D
this.currentPage = currentPage; ~;jgl_5?b
} \s%g'g;
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/** HU'w[r6a
* @return $@@ii+W}\
* Returns the everyPage. 9i U/[d
*/ &',#j]I
publicint getEveryPage(){ ^,YTQ.O
return everyPage; >-\^ )z
} sBYDo{01
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/** BdMd\1eMw
* @param everyPage H#7=s{u
* The everyPage to set. *Lxt{z`9
*/ c0Bqm
publicvoid setEveryPage(int everyPage){ *+zFsu4l
this.everyPage = everyPage; w,X)g{^T
} SHs [te[
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/** m_Pk$Vwx
* @return VQ,5&-9Y3
* Returns the hasNextPage. qtdkK LT
*/ )^BZ,e
publicboolean getHasNextPage(){ f,i2U|1pbj
return hasNextPage; K\KQ(N8F
} y{&%]Fq
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/** I{[}1W3]W
* @param hasNextPage 5k@T{
* The hasNextPage to set. R(pQu!
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*/ P>u2""c
publicvoid setHasNextPage(boolean hasNextPage){ )5n0P
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this.hasNextPage = hasNextPage; 0<:rp]<,
} P5h*RV>oS
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/** X3 1%T"
* @return 0C.5Qx
* Returns the hasPrePage. sxA]o|
*/ RhKDQGdd
publicboolean getHasPrePage(){ cuH5f }oc
return hasPrePage; ppRA%mhZ
} %TR J
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/** J~xm[^0
* @param hasPrePage `q\F C[W
* The hasPrePage to set. mi$C%~]5m
*/ A4|7^Ay
publicvoid setHasPrePage(boolean hasPrePage){ 4[#)p}V
this.hasPrePage = hasPrePage; Y'jgp Vt
} 9mp`LT
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/** |EdEV*.ej
* @return Returns the totalPage. n:B){'S
* A W6B[
*/ g33Y$Xdk
publicint getTotalPage(){ :R=7dH~r
return totalPage; ]hy@5Jyh
} Du
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/** WF*j^ %5
* @param totalPage ?$ov9U_
* The totalPage to set. Dq%}({+
*/ @`+\vmfD
publicvoid setTotalPage(int totalPage){ ^7ID |uMr
this.totalPage = totalPage; shL_{}
} 6W
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} yPT o,,ca=
5D=U.UdR
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7Y-Q, ?1
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 w0@XJH:P
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个PageUtil,负责对Page对象进行构造: >TM{2b,(p
java代码: [O'aka
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/*Created on 2005-4-14*/ \!jz1`]&{
package org.flyware.util.page; 9015PEO
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import org.apache.commons.logging.Log; >);M\,1\I
import org.apache.commons.logging.LogFactory; sw}^@0ua=
rN7JJHV
/** -K$ugDi
* @author Joa & ^1 b]f
* ;qy;;usa
*/ k<j]b^jbz
publicclass PageUtil { :-U&_%#w
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privatestaticfinal Log logger = LogFactory.getLog A-.Wd7^~*
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(PageUtil.class); Z_dL@\#|
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/** vol (%wB
* Use the origin page to create a new page },}g](!m
* @param page ]8OmYU%6V
* @param totalRecords h+!R)q8M
* @return wj0_X;L
*/
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publicstatic Page createPage(Page page, int +:jv )4^O
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totalRecords){ w;(=wN\
return createPage(page.getEveryPage(), q&3(yhx
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page.getCurrentPage(), totalRecords); Z8/.I
} _<2{8>EVf
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/** ~.J*_0~Ze
* the basic page utils not including exception gaNe\
_,v?rFLE
handler tI^[|@,
* @param everyPage pRxVsOb
* @param currentPage FIAmAZH}_
* @param totalRecords %jf|efxo
* @return page 7rbw_m`12-
*/ T*Ge67
publicstatic Page createPage(int everyPage, int A.7lo
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currentPage, int totalRecords){ ?IS[2 v$
everyPage = getEveryPage(everyPage); +_vf=d
currentPage = getCurrentPage(currentPage); ?G7*^y&Q
int beginIndex = getBeginIndex(everyPage, @c"s6h&
c;(Fz^&_
currentPage); 5kWzD'!^
int totalPage = getTotalPage(everyPage, vA ZkT"
@].!}tz
totalRecords); @p/"]zf
boolean hasNextPage = hasNextPage(currentPage, k#~oagW_Gw
*81/q8Az
totalPage); sK9RViqF\
boolean hasPrePage = hasPrePage(currentPage); FqGMHM\J
[AIqKyIr
returnnew Page(hasPrePage, hasNextPage, 9m_~Zs}Z
everyPage, totalPage, nQ|($V1?W
currentPage, Y`$\o
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beginIndex); xe(7q1
} g2^{+,/^K
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privatestaticint getEveryPage(int everyPage){ %qE"A6j
return everyPage == 0 ? 10 : everyPage; EB}~^ aY
} +>2.O2)%q
</5
privatestaticint getCurrentPage(int currentPage){ wL]#]DiE
return currentPage == 0 ? 1 : currentPage; snu?+*6
} ,afO\oe>MG
@ZJ}lED3
privatestaticint getBeginIndex(int everyPage, int |=~mRqG
lfd-!(tXD
currentPage){
JV4fL~
return(currentPage - 1) * everyPage; #h9Gl@|
} t;PG
8'qlg|{!~
privatestaticint getTotalPage(int everyPage, int &w`Ho)P
(Uu5$q(
totalRecords){ .V}bfd[k$
int totalPage = 0; =;Co0Q`
XhWo~zh"
if(totalRecords % everyPage == 0) o$U{.#
totalPage = totalRecords / everyPage; qe
e_wx
else cH:&S=>h
totalPage = totalRecords / everyPage + 1 ; iPG:w+G
'L9hM.+
return totalPage; +eKLwM
} r4X\/
SD8>,
privatestaticboolean hasPrePage(int currentPage){ *V+,X
return currentPage == 1 ? false : true; ea`6J
} ei=u$S.
m]Qs
BK
privatestaticboolean hasNextPage(int currentPage, %BMlcm7Ec
:f_oN3F p
int totalPage){ #uC}IX2n
return currentPage == totalPage || totalPage == FzCXA=m
P\{s C6E
0 ? false : true; ^'Rs`e
} 9jx>&MnWs
M$>Nd6,@N
aZa1 eE
} $[Nf?`f(t_
7zU~X,
U,fPG/9
vflC{,{=k>
>zw@!1{1
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 K)[\IJJM
kVt/Hhd9
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 <HS{A$]
MY z!zI
做法如下: eAjR(\f>
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 63$`KG3
lZ2gCZ
的信息,和一个结果集List: ]-a/)8
java代码: [TqX"@4NS
u}_x
C8)s6
/*Created on 2005-6-13*/ usoyH0t!?
package com.adt.bo; qx*b\6Rt
[0kZyjCq@
import java.util.List; QG
L~??
<m{#u4FC'
import org.flyware.util.page.Page; 2\|sXC
2,Z@<
/** K$:btWSm
* @author Joa >){}nlQf
*/ v6! `H
publicclass Result { -!M>;M@
Q.V@Sawe5
private Page page; nG?Z* n
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private List content; `jhbKgR[
~+Cl9:4T
/** rTJqw@]#WH
* The default constructor 'iwTvkf{
*/ Z?9G2<i
public Result(){ \)aFYDq#\
super(); j':<7n/A
} Pd
`~#!
xH,e$t#@@~
/** 0lOan
* The constructor using fields Y<N#{)Q
* Kg /,
* @param page IC$"\7
@
* @param content + ~,q"6
*/ \FCPD.2s+
public Result(Page page, List content){ i/!KUbt
this.page = page; WHLTJ]OB
this.content = content; d#ab"&$bv
} "Z&_*F.[O
P+_1*lOG
/** "^
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* @return Returns the content. ^ AZv4H*~
*/ P-yVc2YH
publicList getContent(){ C+t|fSJ
return content; Z3u6m0!
} '%TD#!a
dPV<:uO
/** ka(3ONbG
* @return Returns the page. ={6vShG)m
*/ .+u r+"i
public Page getPage(){ 2'Kh>c2
return page; qM3(OvCt
} )`gxaT>&l
H3iYE~^#
/** {S@,
,
* @param content h+YPyeAs
* The content to set. wsAb8U C_
*/ ku>Bxau4>
public void setContent(List content){ 7[R`52pP
this.content = content; ALInJ{X
} 5RY-.c4}
i`}9VaUG
/** r9D
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* @param page *`Ge8?qC
* The page to set. *lheF>^
*/ NNJQDkO-I
publicvoid setPage(Page page){ q 4Ok$~"I
this.page = page; FS!vnl8`
} or7l}X
} l6MBnvi
q!h'rX=_-
#a]\3X
ir|L@Jj,
v!n|X7
2. 编写业务逻辑接口,并实现它(UserManager, 6aWnj*dF
`Uvc^
UserManagerImpl) ,Vz-w;oDn
java代码: "N}MhcdS
DwTVoCC
4JH^R^O<n
/*Created on 2005-7-15*/ U:PtRSdn!b
package com.adt.service; e%9zY{ABR%
G%}k_vi&q
import net.sf.hibernate.HibernateException; .+lx}#-#
tTt}=hQpgX
import org.flyware.util.page.Page; c2Y\bKeN
e%7#e%1s
import com.adt.bo.Result; |a'$v4dCF
$HRl:KDdP~
/** (~"#=fs.L
* @author Joa UZ:z|a3
*/ %hz5)
publicinterface UserManager { Y%(8'Ch
Q5 o0!w
public Result listUser(Page page)throws YCdtf7P=q
Y|KT3
HibernateException; Cw5B
p9
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} @j(2tJ,w
6"r _Y7%
:/>Zky8,k
{aU|BdATI
{817Svp@
java代码: A9GSeW<
:j32 :/u
f]Rh<N$
/*Created on 2005-7-15*/ >LVGNicQ
package com.adt.service.impl; 3A! |M5
xxC2 h3
import java.util.List; p@@*F+
\34:]NM
import net.sf.hibernate.HibernateException; (7??5gjh
sv6m)pwh
import org.flyware.util.page.Page;
LGYg@DR
import org.flyware.util.page.PageUtil; %9L+ Q1o
_.m|Ml,`{
import com.adt.bo.Result; D'UIxc8
import com.adt.dao.UserDAO; |vBy=:
import com.adt.exception.ObjectNotFoundException; ~*tn|?%
import com.adt.service.UserManager; |2jA4C2L}
nHLMF7\
/** xd4~[n\hm
* @author Joa =W gzj|Kr
*/ 0R-W9qP
publicclass UserManagerImpl implements UserManager { Zb<D%9
VwLo
private UserDAO userDAO; )3 '8T>^<K
-O $!sFmY
/** *3fhVl=8^*
* @param userDAO The userDAO to set. CX]L'
*/ gL7rX a j
publicvoid setUserDAO(UserDAO userDAO){ 7oCY@>(f
this.userDAO = userDAO; z)u\(W*\iA
} 8rLhOA
6R#igLm
/* (non-Javadoc) [z'jL'\4
* @see com.adt.service.UserManager#listUser rX?%{M,xFw
]r\!Z
<<(
(org.flyware.util.page.Page) '*G8;91u
*/ r( bA>L*mk
public Result listUser(Page page)throws }Am5b@g"$Y
wxF\enDY
HibernateException, ObjectNotFoundException { \[AJWyP
int totalRecords = userDAO.getUserCount(); }E&:
if(totalRecords == 0) Q-yNw0V}F
throw new ObjectNotFoundException {m_y<
:8A@4vMS)?
("userNotExist"); {WTy/$ Qk
page = PageUtil.createPage(page, totalRecords); xg'xuz$U
List users = userDAO.getUserByPage(page); 79+i4(H
returnnew Result(page, users); DjvPeX
} 59X XmVg
Wo5%@C#M
} H=mFc@fh
G4\|bwh
TRE D_6
P!XO8X 1F
Ggbz
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 R}D[ z7
nPjK=o`KR
询,接下来编写UserDAO的代码: @z`eqG,']
3. UserDAO 和 UserDAOImpl: @=BApuer+
java代码:
cG1iO:
" z -tL
{"|la;*I
/*Created on 2005-7-15*/ j-| !QlB
package com.adt.dao; Bc'Mj=>;
Ou+b ce
import java.util.List; Fx:4d$>;
!Yz
CK*av1
import org.flyware.util.page.Page; ^Iqu ^n?2.
^,`]Q)P^
import net.sf.hibernate.HibernateException; G[{Av5g mx
:G&:v
/** 6;(b-Dhi
* @author Joa =o'g5Be<F
*/ 0#~k)>(7lR
publicinterface UserDAO extends BaseDAO { Yaz/L)Y;R
$v5 >6+-n
publicList getUserByName(String name)throws Af}o/g
e2L>"/
HibernateException; a;\a>N4
apnpy\in
publicint getUserCount()throws HibernateException; Y&bO[(> 1
2#s8Dxt
publicList getUserByPage(Page page)throws Q
/t_%vb
d ]jF0Wx*
HibernateException; (i1p6
uG-S$n"7K
} s|X_:3\x
/[n]t
;J:* r0
n Q{~D5y,,
$9u:Ox
2
java代码: +Eel|)Z*Q
N0N%~3
j]aIJbi
/*Created on 2005-7-15*/ n(CM)(ozU
package com.adt.dao.impl; U~dqxR"Q
FtlJ3fB@
import java.util.List; b;NV vc(
fUPYCw6F
import org.flyware.util.page.Page; c{ qTVi5e
x6^FpNgQ
import net.sf.hibernate.HibernateException; 9#kk5 )J
import net.sf.hibernate.Query; O'QnfpQ*9
12: Q`
import com.adt.dao.UserDAO; XEN-V-Z%*
y.(m#&T
/** *:`fgaIDa
* @author Joa Nnoj6+b
*/ -OnKvpeI
public class UserDAOImpl extends BaseDAOHibernateImpl I.`DBI#-f
H}(WL+7
implements UserDAO { qac:"z'9
r$ I k*R
/* (non-Javadoc) _qh\
* @see com.adt.dao.UserDAO#getUserByName <N3~X,ch
V}Oz!
O
(java.lang.String) KIKIag#
*/ JOs
kf(
publicList getUserByName(String name)throws ^ (J%)&_\3
T7l,}G
HibernateException { p4kK"
\ln
String querySentence = "FROM user in class 7Q,<h8N\5
u#Bj#y!
com.adt.po.User WHERE user.name=:name"; Ak$9\Sl
Query query = getSession().createQuery J?tnS6V
6="o&!
(querySentence); \x5>H:\Y
query.setParameter("name", name); ZT`"
{#L
return query.list(); MJa`4[/
} "#iO{uMWb
TJB4N$-}A
/* (non-Javadoc) eKU4"XTk
* @see com.adt.dao.UserDAO#getUserCount() Oi{J}2U
*/ K7/&~;ZwT
publicint getUserCount()throws HibernateException { P2U4,?_e
int count = 0; ?}EWfsA
String querySentence = "SELECT count(*) FROM v
"[<pFj^
aJc>"#+
o
user in class com.adt.po.User"; :_+U[k(#
Query query = getSession().createQuery K9K.mGYc
XXQC`%-]<i
(querySentence); ::3[H$
count = ((Integer)query.iterate().next 4#I=n~8a
{}=5uU 2Tu
()).intValue(); ^9YS dFH/
return count; ^PMA"!n8
} 8v)HTD/C
0BAZWm
/* (non-Javadoc) _T=";NSa
* @see com.adt.dao.UserDAO#getUserByPage `wSoa#U"@
^E%NYq_2l<
(org.flyware.util.page.Page) mM_gOd
*/ H)y_[:[
publicList getUserByPage(Page page)throws Z+4Mo*#
+?5Vuc%
HibernateException { VP7LKfv
String querySentence = "FROM user in class 0/cgOP!^
6vzvH
com.adt.po.User"; U8%IpI;
Query query = getSession().createQuery E^~ {thf
&]anRT#
(querySentence); (X (:h\^
query.setFirstResult(page.getBeginIndex()) ]eTp?q%0
.setMaxResults(page.getEveryPage()); ol`q7i.
return query.list(); &?gcnMg$,J
} R/2L9Lcv
HD,6
} n"R$b:
Lf{pTxKr
CM`Q((
+.$:ZzH#
2Ns<lh
至此,一个完整的分页程序完成。前台的只需要调用 $0]5b{i]
9N|JI3*41
userManager.listUser(page)即可得到一个Page对象和结果集对象 9yLPh/!Ob
s,D GFK
的综合体,而传入的参数page对象则可以由前台传入,如果用 H/*i-%]v+(
")fgQ3XZ
webwork,甚至可以直接在配置文件中指定。 K5(T7S
x26 sH5
下面给出一个webwork调用示例: HhzP Kd
java代码: j",*&sy
1o)<23q`)
Ysi@wK-LnF
/*Created on 2005-6-17*/ P+3
]g{2w
package com.adt.action.user; !=+;9Ry$z
Q0xQxz
import java.util.List; Z(J
1A x
8"u.GL.
import org.apache.commons.logging.Log; ?w)A`G_
import org.apache.commons.logging.LogFactory; i_I`
import org.flyware.util.page.Page; 475jmQ{q
zD
sV"D8
import com.adt.bo.Result; &d"scM5
import com.adt.service.UserService; >q&e.-qL
import com.opensymphony.xwork.Action; h@s i)5"
J,=^'K(
/** +ERuZc$3,
* @author Joa paxZlA
o
*/ #EH\Q%
publicclass ListUser implementsAction{ TI8EW
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[
privatestaticfinal Log logger = LogFactory.getLog C{6m?6
qtP*O#1q
(ListUser.class); uYd_5
nw
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private UserService userService; ^SwU]e
E/E|*6R
private Page page; &(20*Vn,O
mUiJ@
privateList users; (k%r_O 6
zK*i:(>B
/* 8#Y_]Z?)
* (non-Javadoc) d~b@F&mf
* GVdJ&d\x
* @see com.opensymphony.xwork.Action#execute() /EvT%h?p
*/ 6p14BruV
publicString execute()throwsException{ Rr\fw'
Result result = userService.listUser(page); X)8Edw[?N3
page = result.getPage(); i2\CDYP
users = result.getContent(); \9}-5
return SUCCESS; G2J4N2hu
} FWS!b!#,N
BkDq9>
/** CTc#*LJx>j
* @return Returns the page. z}p*";)A
*/ }5?|iUH|
public Page getPage(){ b+71`aD0
return page; W#9LK
Jj
} /NVyzM51V
zG&yu0;D6
/**
y $L&N0z
* @return Returns the users. jgw+c3^R_
*/ k6_OP]
publicList getUsers(){ j*_#{niy:
return users;
5)M#hx%]#
} o^BX:\}
Vb~;"WABo
/** l+O\oD?-
* @param page b28C(
* The page to set. AE%zqvp>
*/ Ude)$PAe%
publicvoid setPage(Page page){ YMn=9EUp
this.page = page; m9aP]I3g]\
} ;7!u(XzN
+#g4Crb
/** g^:7mG6C
* @param users FsfP^a
* The users to set. &F +hh{
*/ SS-7y:6y>
publicvoid setUsers(List users){ @ds.)sKA>
this.users = users; mmEe@-lE
} 1.j;Xo/+:V
<U""CAE
/** DQ_ pLXCC
* @param userService ?yvjX90
* The userService to set. 6x!
q
*/ "ODs.m oq
publicvoid setUserService(UserService userService){ Eb\SK"8
this.userService = userService; w Yr M2X@
} ==~
lc;
} rcjj(
C
,wk %)^
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" G0HsXi
X1lL@ `r.5
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, I~7eu&QZ
<ApzcyC
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 v
iM6q<Ht
U~{sJwB
么只需要: ;S^7Q5-
java代码: e/ V8lo
J"]P"`/
E3o J;E
<?xml version="1.0"?> wLH[rwPr
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork Fu#mMn0c
R9V v*F]m@
1.0//EN" "http://www.opensymphony.com/xwork/xwork- /s^O M`5
wr;8o*~
1.0.dtd"> (8OaXif
@K.[;-;g
<xwork> HESORa;
?W4IAbT\G
<package name="user" extends="webwork- I:%O`F
xk8P4`;d$
interceptors"> tV,Y38e
or1D
6*'
<!-- The default interceptor stack name +MP`iuDO
`l8^n0-
--> `?R~iLIAq
<default-interceptor-ref ?-IjaDC}
}J&[Uc
name="myDefaultWebStack"/> %rZJ#p[e)=
+c^[[ K"
<action name="listUser" C@i4[g){
#x;i R8^
class="com.adt.action.user.ListUser"> 3mnq=.<(w
<param -Am~CM
S+EC!;@Xg
name="page.everyPage">10</param> -h<Rby
<result SMdQ,n1]
amK.H"
name="success">/user/user_list.jsp</result> Fn~?YN
</action> ^s&1,
2_]"9d4
</package> A!Ls<D.
~L.)<{?
</xwork> 'rwnAr
sOBy)vq?\
(PmaVwF
"e\:Cq>\
,#PeK(
f._FwD
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 n-7|{1U
`_{^&W
WS
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。 3+/{}rv
T>ds<MaLP
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 >1=sw
qa
.?YLD+\A
[9E<z2H
Wl:vO^
>}~Pu|
_S
我写的一个用于分页的类,用了泛型了,hoho b4$-?f?V
{b^JH2,
java代码: D d$ SQ
cDS6RO?
W/m,qilQI
package com.intokr.util; KXP^F6@l
+)4_1i4"x
import java.util.List; jHj*S9:`
od\Q<Jm}
/** "&ElKy
7j
* 用于分页的类<br> vq~btc.p{&
* 可以用于传递查询的结果也可以用于传送查询的参数<br> )(|+z'
* k%?fy
* @version 0.01 jc|"wN]
* @author cheng 7Xu.z9y
*/ /pvR-Id|6
public class Paginator<E> { lth t'|
privateint count = 0; // 总记录数 a~_5N&~pi
privateint p = 1; // 页编号 BiQ7r=Dd.
privateint num = 20; // 每页的记录数 V3'QA1$
privateList<E> results = null; // 结果 =Zcbfo_&
P%v7(bqL4+
/** TixXA:Mf
* 结果总数 UGNFWZ c
*/ %Bo/vB'
publicint getCount(){ e5_:15%R\
return count; *5bKJgwJ
} !biq7f%6#
#TLqo(/
publicvoid setCount(int count){ 821@qr|`e
this.count = count; Cebl"3Q
} H[ DrG6GA
Z?H#=|U
/** L=u>}?!,Fj
* 本结果所在的页码,从1开始 &}P{w
* kETu@la}
* @return Returns the pageNo. $2=-Q/lM
*/ )E<<