Java 正在检索hashmap中的列表。
我试图从hashmap中检索列表值,但它正在显示com.action。ReportClass@10da25f. 这里ReportClass是Pojo类,我在其中设置了我的resultset数据Java 正在检索hashmap中的列表。,java,list,jsp,collections,hashmap,Java,List,Jsp,Collections,Hashmap,我试图从hashmap中检索列表值,但它正在显示com.action。ReportClass@10da25f. 这里ReportClass是Pojo类,我在其中设置了我的resultset数据 package com.pkg; import java.sql.Connection; import java.sql.ResultSet; import java.sql.Statement; import java.util.ArrayList; import java.util.HashMap
package com.pkg;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;
public class JanuaryAction {
private String from; // creating variables to access input values.
private String to; // creating variables to access input values.
Map abc1 = new HashMap(); // Getting the map objects to store tha values
public Map getAbc1() { /* Creating the setters and getters */
return abc1;
}
public void setAbc1(Map abc1) {
this.abc1 = abc1;
}
public String getFrom() {
return from;
}
public void setFrom(String from) {
this.from = from;
}
public String getTo() {
return to;
}
public void setTo(String to) {
this.to = to;
}
public Map<String, String> getAbc() {
return abc;
}
public void setAbc(Map<String, String> abc) {
this.abc = abc;
}
Map<String, String> abc = new HashMap<String, String>();
Map<String, List<ReportClass>> map = new HashMap<String, List<ReportClass>>(); // Using
// Map
// interface
// implementing
// hashmap
public Map<String, List<ReportClass>> getMap() {
return map;
}
public void setMap(Map<String, List<ReportClass>> map) {
this.map = map;
}
public String execute() throws Exception {
String fromdate = getFrom();
System.out.println(fromdate);
String todate = getTo();
System.out.println(todate);
Connection con = GetCon.getCon();
Statement statement = con.createStatement();
ResultSet resultset = statement
.executeQuery("SELECT MarketPlace,OrderDate, ROUND(SUM(Total),2), COUNT(*) , ROUND(ROUND(SUM(Total),2)/ COUNT(*),2) FROM vend_printed WHERE OrderDate >='"
+ fromdate + "' AND OrderDate <='" + todate + "' GROUP BY OrderDate,MarketPlace");
while (resultset.next()) {
String marketplace = resultset.getString(1);// get the first column
// in marketplace
String orderdate = resultset.getString(2);// get the second column
// in orderdate
Double datamount = resultset.getDouble(3);// get the third column in
// datamount
Integer count = resultset.getInt(4);// get the fourth column in
// count
Double result = resultset.getDouble(5); // get the fifth column in
// result
ReportClass a = new ReportClass(); // create an object to access
// pojo class.
a.setMarketplace(marketplace); // setting the values in pojo class
a.setOrderdate(orderdate);
a.setDataamount(datamount);
a.setCount(count);
a.setResult(result);
if (map.get(marketplace) != null) { // if the value in marketplace
// is null then go to else
// statement or go to if
// statement.
map.get(marketplace).add(a); // using the key add one complete
// row values from a to
// marketplace
} else {
List<ReportClass> optionsVO = new ArrayList<ReportClass>(); // create
// a
// list
// optionsVo
optionsVO.add(a); // store Reportclass values in List.
map.put(marketplace, optionsVO); // storing it in map.
/* System.out.println(map.get(marketplace).toString()); */
}
}
Set s = map.entrySet(); // A map entry (key-value pair).creating Set
// interface.
Iterator i = s.iterator();
while (i.hasNext()) {
List<ReportClass> tempList = (List<ReportClass>) ((Entry) i.next()).getValue(); // creating
// a
// temporary
// list
for (ReportClass reportClassObj : tempList) {
System.out.println(reportClassObj.getMarketplace());// display
// values.
System.out.println(reportClassObj.getDataamount());
System.out.println(reportClassObj.getOrderdate());
System.out.println(reportClassObj.getCount());
System.out.println(reportClassObj.getResult());
}
}
/* System.out.println(map.size()); */
return "success";
}
}
在我的jsp中,我有一个代码
<s:iterator var="studentEntry" status="stat" value="map.entrySet()">
Student Key: <s:property value="%{#studentEntry.getKey()}"/>
Student Value: <s:property value="%{#studentEntry.getValue()}"/><br>
</s:iterator>
您直接打印ReportClass对象,它打印该对象的hashcode值。您需要重写类的toString方法以获得对象的有意义的文本表示
我猜您正在使用eclipse。只需在编辑器上单击鼠标右键,然后单击OverrideTostring。在这里,您可以选择要放入表示中的字段
这里有一个例子
包com.compare
public class Person {
private String firstName;
private String lastName;
public String getFirstName() {
return firstName;
}
public void setFirstName(String firstName) {
this.firstName = firstName;
}
public String getLastName() {
return lastName;
}
public void setLastName(String lastName) {
this.lastName = lastName;
}
@Override
public String toString() {
return "Person [firstName=" + firstName + ", lastName=" + lastName
+ "]";
}
public static void main(String [] args){
Person person = new Person();
person.setFirstName("Prasad");
person.setLastName("kharkar");
System.out.println(person);
}
}
这将生成以下输出
Person [firstName=Prasad, lastName=kharkar]
您直接打印ReportClass对象,它打印该对象的hashcode值。您需要重写类的toString方法以获得对象的有意义的文本表示
我猜您正在使用eclipse。只需在编辑器上单击鼠标右键,然后单击OverrideTostring。在这里,您可以选择要放入表示中的字段
这里有一个例子
包com.compare
public class Person {
private String firstName;
private String lastName;
public String getFirstName() {
return firstName;
}
public void setFirstName(String firstName) {
this.firstName = firstName;
}
public String getLastName() {
return lastName;
}
public void setLastName(String lastName) {
this.lastName = lastName;
}
@Override
public String toString() {
return "Person [firstName=" + firstName + ", lastName=" + lastName
+ "]";
}
public static void main(String [] args){
Person person = new Person();
person.setFirstName("Prasad");
person.setLastName("kharkar");
System.out.println(person);
}
}
这将生成以下输出
Person [firstName=Prasad, lastName=kharkar]
在reportclass中使用此选项
@Override
public String toString() {
return "orderdate is: " +orderdate+ ", No of order is: "+dataamount+ ", Total Order is: " +count+ ", Reuslt is: "+result;
}
}
在reportclass中使用此选项
@Override
public String toString() {
return "orderdate is: " +orderdate+ ", No of order is: "+dataamount+ ", Total Order is: " +count+ ", Reuslt is: "+result;
}
}
你需要重写ReportClass中的toString方法。如果你能给我举个例子,我是新手,你可以用我写的上面的内容进行谷歌搜索,我将不胜感激。搜索重写Java中的toString你需要重写ReportClass中的toString方法。如果你能给我举个例子,我是新手,如果你能用我写的上述内容进行google搜索,我将不胜感激。我很高兴我能提供帮助:你能告诉我如何在我的案例中实现吗。我不知道该怎么做。我很高兴我能帮上忙:你能告诉我在我的案例中该如何实现吗。我不知道该怎么办。