Here is my HashMap and a method for listing all the keys in it
HashMap<String, String> exampleOne = new HashMap<String, String>();
public void allKeys() {
int i;
i =0;
for (String name: exampleOne.keySet())
[Code]....
Now I want to return all values that associated with one key. How do I do this? Or is it possible to other way round? I mean return All keys associated with a value?
I have one doubt.In HashMap if keys contains 1,2,3,4 and values are a,b,c,d we can get values using get(key) method like 1 will A,2 will return B and so on. Can we get the keys from values like A will get 1 and also if in key if there is a String like 1,2,3,Z and value is A,B,C,7 Z should get me 7. Here I am not using any generics.
View Replies View RelatedI am asked in my assignment to make a program that accepts a text file as an example a novel and i have to sort each word as a PERSON or ORGANIZATION or LOCATION or O as in Other , example :
Microsoft/ORGANIZATION ,/O Nelly/PERSON !/O '/O
Now we notice that microsoft is and organitzation and "," is Other and Nelly is a person's name and so on ..
Now I am asked to return the numbers of tags in the text which is 4 in our case because we have (ORGANIZATION,PERSON,LOCATION,OTHER)
My question here is my logic true ? And since i made a map of String,String ; Is there any way that i can get the size of the values in our case the values are the organization etc.. ?
import java.io.File;
import java.io.FileNotFoundException;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
[code].....
I want to write a method to print the all the names of a phone book. phoneBook is a HashMap<String, String> , that has names as keys and phone numbers as values.
Reading the documentation for both HashMap and Set, I have more or less an idea of how it could be done but I cant put it on code..
public String getName()
{
String[] keys = phoneBook.keySet().toArray();
return keys[0];
}
This is wrong. It doesnt compile saying incompatible types. I was thinking first to manage to succeed to get a key from my phone book and then I change it to print all the keys.
I have the following hashMap declared:
private HashMap<String, Car> cars = new HashMap<String, Car>();
How can i get an array of String filled with hashMap keys?
My objective here is to process a HashMap's key's in order. I found SortedSet as a way to do it.
The HashMap is like this:
nobelPrizeWinners = new HashMap<String, PrizeWinner[]>();
// 2009:
nobelPrizeWinners.put(new String ("2009 Physics"), new PrizeWinner[] {new PrizeWinner("Charles K.", "Kao"), new PrizeWinner("Willard S.", "Boyle"), new PrizeWinner("George S.", "Smith")});
[Code] ....
This is the method I am trying to write
public void displayAllYearsAndWinners_2()
{
// Creation of the SortedSet
SortedSet sortedSet = new TreeSet();
[Code] ....
However, the compiler gives me a warning of NobelPrizeWinners.java uses unchecked or unsafe operations. Recompile with -Xlint:unchecked for details.
As I said, my objective here is to process them in order. If this compiler warning cannot be resolved, I am open to other methods of accomplishing my objective.
I'm learning Java using BlueJ, I have made a class that has a HashMap of (String, String) that contains an the make of a car and the model.
I want a method to return a collection of all the keys that satisfy a condition, like if someone wants to find what make a certain model is. I know it requires a loop, just not too sure how to write the loop to satisfy the condition.
How do i take input values for TwoDPoint (which are objects) and return it back in numerical values also print them.
When i create an object in main method and pass values to my function of return type TwoDPoint,it gives error:- found int,int need TwoDPoiint,TwoDPoint.
// Here is what i tried to do:
Created class TwoDPoint that contains two fields x, y which are of type int. Defined another class TestTwoDPoint, where a main method is defined.In the main method created two TwoDPoint objects.
Then I modified the class TestTwoDPoint and add another function to it. This function takes two TwoDPoints as input and returns the TwoDPoint that is farthest from the point (0,0).
Then I added another function to TestTwoDPoint. This function takes two TwoDPoints as input and returns a new TwoDPoint whose x value is the sum of x values of the input TwoDPoint's and whose y value is the sum of the y values of the input TwoDPoint's.
class TwoDPoint {
int x = 2;
int y = 4;
}
class TestTwoDPoint {
public static void main(String args[]) {
TwoDPoint obj1 = new TwoDPoint();
System.out.println(obj1.x);
System.out.println(obj1.y);
[Code] ....
I have a 2D array and the elements are listed as follows:
outlook temperature humidity windy gooutside
sunny hot high false n
overcast hot high false y
....
I need to put these values into a HashMap, where the elements of the first row are the keys and the elements from row 1 to n-1 are the values. What would be the best way to make sure the key and values are matched correctly?
Here is what I have:
String[][] array = new String[numberOfRows][numberOfCols];
HashMap<String, String> map = new HashMap<String, String>();
for(int rows = 0; rows < (numberOfRows * numberOfCols); rows++) {
for(int cols = 0; cols < array[i].length; cols++} {
map.put(array[0][cols], array[rows*cols][col];
}
}
I keep getting the out of bounds error.
Currently working on a simple file processing problem, namely, reorder a set of strings (called bid phrases) in terms of the score value associated to them in descending order.
My code outputs everything in ASCENDING order.
How to twist HashMap values around?
import java.io.BufferedReader;
import java.io.FileReader;
import java.io.FileWriter;
[Code].....
I am working on the Kevin Bacon - 6 degrees of bacon problem. I want to take my Array List and use the index and Values that I have saved in it as the Key and Value of a Hashmap. Below is my code.
HashMap<Integer, ArrayList<String>> actors =
new HashMap<Integer, ArrayList<String>>();
ArrayList array = new ArrayList();
try (BufferedReader br = new BufferedReader(
new FileReader("actors.txt"));)
[code]...
saving each one in it's own spot. I want to use the index of each one as the key to find it in the Hashmap....
I need assigning the selected hashmap values into a list and to display the values in a jsf page. The user will select certificates and will be stored in the below list:
private List<String> selectedCertificates = new ArrayList<String>();
The selectedCertificates will have the values ("AA","BB"). Now I will be passing the list into a hashmap in order to get the names and to display them on the jsf page.
My code is below:
Map<String, String> CertificatesNames =
new HashMap<String,String>(selectedCertificates.size());
CertificatesNames.put("AA", "Certificate A");
CertificatesNames.put("BB", "Certificate B");
CertificatesNames.put("CC", "Certificate C");
for(String key1: selectedCertificates) {
System.out.println(CertificatesNames.get(key1));
}
I want to display in my jsf page :
Certificate A
Certificate B
Now my issue is that is how to display all the values of the CertificatesNames.get(key1) in the jsf page as I tried to do the below and it printed all the values when I used the #{mybean.beans} using the :
List beans =
new ArrayList(CertificatesNames.values());
So how to do this?
I have a question in mind that this is my registration form. I am sending these values from HTML form to server and database. I have question that in my case if I click next to Add Another Mobile no in HTML.then a block is genereated and each time a new name is generated.
My Question is if I click 6 times then 6 name attribute are generated. How can I send and differentiate them on my server side.
Because at their I will use something request.getAttribute("Attr_Name");
But they are same. How to do this?.
I have a class, which communicates with database via SQL queries. But one queries don't produce any ResultSet, while other queries do. Now I'm facing situation, where I have two methods, one which executes queries with return values and other which executes queries without return values:
public ResultSet executeQueryWithReturn(String query){
try{
return executeWithReturn(query);
}catch(Exception e){
e.printStackTrace();
[Code] .....
But I see few problems here: 1) Method can return null, (I read in book Clean Code, that people should avoid return null) Another issue - boolean value breaks the rule that method should do only one thing.
Maybe there is a better option? or maybe I should forget these two issues here for readability?
I have the folowing method i what to return two values
public String[] getChildRoles()
return this.getUserTypes() + this.getUsernew();
}
All the samples I found use JOptionPane to return a single value. I am looking to return two values from two Text fields.
View Replies View RelatedI have attempted on my own many times but I am not getting any closer to a solution.
/**
* Returns a SmartArray with eight values. The values are the values stored in the 8 neighbors of the array cell at the given location in the Smart2DArray.
* Start with the neighbor to the "north" of the given cell and proceed clockwise, using -1 as the value if the neighboring cell is outside the Smart2DArray.
For example, if the array is:
1 2 3
4 5 6
7 8 9
neighbors(1, 1) should return a SmartArray with the values:
2 3 6 9 8 7 4 1
in that order.
neighbors(2,1) should return a SmartArray with the values:
3 -1 -1 -1 9 8 5 2
in that order.
*/
public SmartArray neighbors (int col, int row) {
}
I am trying to write a program that will take any comma separated data set and return the values in an arraylist without any commas. Like if I input "hello, world, program, java" it would output an arraylist [hello,world,program,java].
public void run(){
String line = readLine("Enter a CSV-formatted line of data: ");
int lowerBound = 0;
String entry = new String("");
ArrayList<String> string = new ArrayList<String>();
[Code] .....
I am making a java swing program. I have a main window that opens a JForm window when the user clicks a menu option. Then I have a button on the JForm that closes the window on click. However, I would also somehow like to make the JForm return values to the main window (according to the states of the selector components) when it is closed. How would I go about this? Currently my jForm is a seperate class called "NewGame", and inside the menu item mouse clicked method, I have the following code:
//open new game jform window
NewGame newGameWindow = new NewGame();
newGameWindow.setVisible(true);
newGameWindow.setLocationRelativeTo(null); //center window
Is there something I can add here to get the object's values upon the window's close? Or is there a way I can add that into the button clicked method on the actual jForm?
I want to return multiple values in my EJB query. The query goes something like this:
SELECT SUM(s.sales) SUM(s.cancels) FROM accounts.
To implement this if I write as below:
Query query = _em.createNamedQuery("Accounts.findAccountData");
Now if I do query.getSingleResult(); how do i retrieve both the values since the ejb finder returns either a single object or a collection?.
Write a complete Student class that allows you to use the statements such as the following in methods in outside classes, with the obvious meanings. Then write an application program that creates one student object, reads in test grades until a negative "grade" is seen (as a signal that the list of grades has ended), then prints out all available information about the Student:
Student bob = new Student ("Robert", "Newhart");
bob.storeGrade (23); // bob scored 23 on this test
return bob.getTotalGrades();; // total of test scores to date
return bob.getAverageGrade();; // for all test scores to date
return bob.getName();; // returns "Robert Newhart"
What I need is in the Student class... I'm not sure how to go about storing the grades without renewing the value of storeGrade (I'm sure what I have right now is incorrect, but I'm stuck). This is what I have so far, as you can see I left some of the grade-related bits blank for now, but all I want to know is how I can store the grades:
Java Code:
public class Student extends Object
{
private int itsTotalGrades;
private int itsAverageGrades;
private String itsFirstName;
private String itsLastName;
private int storeGrade;
public Student (String first, String last)
[Code] ....
Write method distance to calculate the distance between two points (x1, y1) and (x2, y2). All numbers and return values should be of type double. Incorporate this method into an application that enables the user to enter the coordinates of the points.
Hints:
- The distance between two points can be calculated by taking the square root of
( x2 - x1 )2 + ( y2 - y1 )2
- Use Math class methods to compute the distance.
- Your output should appear as follows:
Type the end-of-file indicator to terminate
On UNIX/Linux/Mac OS X type <ctrl> d then press Enter
On Windows type <ctrl> z then press Enter
Or Enter X1: 1
Enter Y1: 1
Enter X2: 4
Enter Y2: 5
Distance is 5.000000
Type the end-of-file indicator to terminate
On UNIX/Linux/Mac OS X type <ctrl> d then press Enter
On Windows type <ctrl> z then press Enter
Or Enter X1: ^Z
Can I assign multiple values to one variable? For example I want myNum = 0 thru 9 you see im trying to program a password checker program to verify that the password meets all the criteria 8 char long, 1 upper case, 1 lower case, 1 numeric, 1 special, and don't contain and or end
View Replies View RelatedThe below program ask the user to enter the value of x 1 , Y 1 and radius in separate boxes , What would look nice is if the user can Enter the Value X ,Y and radius in the same box.
import javax.swing.JOptionPane;
public class C3E29GeometryTwoCircles {
public static void main(String[] args) {
// Ask the user to enter the x1 coordinate.
String strNumber = JOptionPane.showInputDialog("Enter the value of x1 coordinate " );
double x1 = Double.parseDouble(strNumber);
strNumber = JOptionPane.showInputDialog("Enter the value of y1 coordinate " );
double y1 = Double.parseDouble(strNumber);
[code]...
I am making use of NetBeans IDE 8.0 to build a GUI. The idea is that I set multiple values received from textfields to textarea. This will enable me print the work. But ONLY ONE value from textfields is set(appear on textarea); the others do not appear at all. Below is example of what I mean:
String s = jTextField1.getText();
JTextArea1.setText(s);
String x =
jTextField2.getText();
JTextArea1.setText(x);
Only one is being set. The rest are not.
I want to use a method, which takes for example an int and also returns an integer. For example, if the the given integer is strong return a, if it is notstrong return b. How would you write that in a Code?
I want to use that in a more general way. I want to give a method mlong the value X of the type date and let it return an int. Type date consists of 3 int, one of them is the int month.
mlong should return an int depending on the X.moth. at the moment my code looks like this:
// File1:
public class date {
public int day;
public int month;
public int year;
}
// File 2:
public class monthlength {
public int mlong(date X) {
int t;
t = X.month;
if (t == 1 || t == 3 || t == 5 || t == 7 || t == 8 || t == 10 || t == 12)
{ return 31; }
if(t == 4 || t == 6 || t == 9 || t == 11)
{return 30;}
}
}