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Replace strings populated in an ArrayList<String> with other values

I am currently working on a project where I need to check an arraylist for a certain string and if that condition is met, replace it with the new string.
I will only show the relevant code but basically what happened before is a long string is read in, split into groups of three, then those strings populate an array. I need to find and replace those values in the array, and then print them out. Here is the method that populates the arraylist:
private static ArrayList<String> splitText(String text)
{
ArrayList<String> DNAsplit = new ArrayList<String>();
for (int i = 0; i < text.length(); i += 3)
{
DNAsplit.add(text.substring(i, Math.min(i + 3, text.length())));
}
return DNAsplit;
}
How would I search this arraylist for multiple strings (Here's an example aminoAcids = aminoAcids.replaceAll ("TAT", "Y");) and then print the new values out.
Any help is greatly appreciated.

In Java 8
list.replaceAll(s-> s.replace("TAT", "Y"));

There is no such "replace all" method on a list. You need to apply the replacement element-wise; the only difference vs doing this on a single string is that you need to get the value out of the list, and set the new value back into the list:
ListIterator<String> it = DNAsplit.listIterator();
while (it.hasNext()) {
// Get from the list.
String current = it.next();
// Apply the transformation.
String newValue = current.replace("TAT", "Y");
// Set back into the list.
it.set(newValue);
}
And if you want to print the new values out:
System.out.println(DNAsplit);

Why dont you create a hashmap that has a key-value and use it during the load time to populate this list instead of revising it later ?
Map<String,String> dnaMap = new HashMap<String,String>() ;
dnaMap.push("X","XXX");
.
.
.
dnaMap.push("Z","ZZZ");
And use it like below :
//Use the hash map to lookup the temp key
temp= text.substring(i, Math.min(i + 3, text.length()));
DNAsplit.add(dnaMap.get(temp));

Returning HashMap values and keys through an array method

I'm trying to return keys and values through an array method.
I have done this:
public ArrayList<String> translationList() {
for (String key : translations.keySet()) {
System.out.println(key + " = ");
}
return new ArrayList<String>(this.translations.values());
}
And in my Main.java
ArrayList<String> translations = dictionary.translationList();
for (String translation : translations) {
System.out.println(translation);
}
It returns
apina =
cembalo =
banaani =
monkey
harpsichord
banana
I'm not sure how to get them to print on the same line after the translation of the word. I know it's printing the for loop before returning the array but that is where my problem is and not sure how to solve it.

Since you are getting only values back there is no way to get key based on value. So hence not possible.
What you can do is return keys from method and iterate that in your method.
or simply change your method to
public ArrayList<String> translationList() {
List<String> returnList = new ArrayList<>(String);
for (Entry<Integer, String> entry : testMap.entrySet()) {
returnList.add(entry.getKey()+"="+entry.getValue());
}
return returnList;
}
and in your main method
ArrayList<String> translations = dictionary.translationList();
for (String translation : translations) {
System.out.println(translation);
}

How to compare values in different collections that need different type of iteration loops?

Lets say you have an Iterator which will contains values that you need to compare with values that are located in a separate List.
Iterator<Map.Entry<String, Object>> it = aObj.items();
while (it.hasNext()) {
Map.Entry<String, Object> item = it.next();
nameValue = item.getNameValue();
keyValue = item.getKeyValue();
System.out.println("Name: " + nameValue);
System.out.println("Value: " + keyValue);
}
This outputs:
Name: header
Value: 22222
Lets say you have a separate list (in which you want to compare the above values with):
List<Items> items = new ArrayList<>();
for (Item item : items) {
itemNameValue = item.getName();
itemKeyValue = item.getKey();
System.out.println("Name: " + itemNameValue);
System.out.println("Value: " + itemKeyValue);
}
This outputs:
Name: header
Value: 44444
Since these are different types of loops (one is a while loop and the other one is a for each loop)
how can you compare for example:
if (nameValue.equals(itemNameValue())) {
// do something?
}
I need to iterate over both collections / data structures at the same time...
Would this be the solution?
String nameValue = "";
Object keyValue = "";
String itemNameValue = "";
String itemKeyValue = "";
Iterator<Map.Entry<String, Object>> it = aObj.items();
while (it.hasNext()) {
Map.Entry<String, Object> item = it.next();
nameValue = item.getNameValue();
keyValue = item.getKeyValue();
for (Item item : items) {
itemNameValue = item.getName();
itemKeyValue = item.getKey();
}
if (nameValue.equals(itemNameValue())) {
// do something?
}
}
Basically, what I am trying to ask (in a very simplified way is this):
(1) The collection that needs to be iterated in a while loop is just test input (sample data)
(2) The array list from the second collection is really a list of data which was returned from a database call (DAO) and placed into the ArrayList.
I am trying to verify if the input from Iterator inside the while loop is the same as the values from the ArrayList (which came from a database). Since these are different data structures requiring different looping mechanisms. How could I iterate through both data structures at the same time and compare them? The second data structure (the array list) is the actual set of values that are correct.
I don't know if there's a guarantee that each iteration would be comparing the same items if I use a nested loop?
Thank you for taking the time to read this...

The problem you are facing is a direct result of a BAD Application design.
The underline incorrect assumption of this question is that the map and the list will hold the objects in the same sequence.
List --> A data structure that is ordered by not sorted
Map --> A data structure that is neither ordered nor sorted
This is not to say that these two data structures don't work well together. However, using them to store the same list should only result from an awkward program design.
Even though to answer your question, you can use the below code to accomplish this:
Iterator<Map.Entry<String, Object>> it = aObj.items();
List<Items> items = dbCall.getItems(); // Get the list of Items from the DB
int index = 0;
while (it.hasNext()) {
Map.Entry<String, Object> itemFromMap = it.next();
Item itemFromList = items.get(index);
if(itemFromMap.getNameValue().equals(itemFromList.getName()) &&
itemFromMap.getKeyValue().equals(itemFromList.getKey())){
// If you prefer a single .equals() method over &&, then you can implement a Comparator<Item>
return false;
}
index++;
}
return true;

ArrayList Java String remove doesnt delete

I am working with Arraylist of objects.
while i already succeeded in delete values from Arraylist while they are numeral.
i'm having trouble delete from arraylist while they are String
here is the example :
public class ArrayListDemo {
public static void main(String[] args) {
// create an empty array list with an initial capacity
ArrayList<Namer> arrlist = new ArrayList<Namer>( );
// use add() method to add values in the list
arrlist.add(new Namer("1","A","G"));
arrlist.add(new Namer("2","E","G"));
arrlist.add(new Namer("3","F","G"));
System.out.println("Size of list: " + arrlist.size());
// let us print all the values available in list
for (Namer value : arrlist) {
System.out.println("age = " + value.age);
}
arrlist.remove("3");
System.out.println("Now, Size of list: " + arrlist.size());
for (Namer value : arrlist) {
System.out.println("age = " + value.age); //System.out.println("Value = " + value);
}
}
}
and the result of running it proof it doesnt deleted the spesific row
i need to delete if with String and cant use number as "Key" .
Size of list: 3
age = 1
age = 2
age = 3
Now, Size of list: 3
age = 1
age = 2
age = 3
what can i make it to work with String in order to delete ?
if that's help
this is the object of arrayList
public class Namer
{
// instance variables - replace the example below with your own
public String age;
public String name;
public String L_name;
public Namer(String a, String na , String Lname)
{
// initialise instance variables
age =a;
name=na;
L_name=Lname;
}
}

You have Namer objects in your ArrayList, not Strings. When you call remove("3"), the ArrayList will look for an object that returns true when equals is called on it with "3". Of course, no String will compare equals with any Namer.
You must do the comparison yourself with the name field, and remove the appropriate item. This can be done with an Iterator and its remove method.

You have to use the object or the index to remove and you are not using either ...
Try this code :
arrlist.remove(2);
or
// create an empty array list with an initial capacity
ArrayList<Namer> arrlist = new ArrayList<Namer>( );
Namer namer1= new Namer("1","A","G");
Namer namer2= new Namer("2","E","G");
Namer namer3= new Namer("3","F","G");
// use add() method to add values in the list
arrlist.add(namer1);
arrlist.add(namer2);
arrlist.add(namer3);
arrlist.remove(namer3);

The method arrlist.remove(idx) takes as paramenter the (interger) index of the element to be removed from the array. There's no such thing as a "key" for ArrayLists.
You probably want to use java.util.Map<Integer,Namer>.

Java Parsing Using Hmap

I am new to Java. I want to Parse the data which is in this Format
Apple;Mango;Orange:1234;Orange:1244;...;
There could be more than one "Orange" at any point of time. Numbers (1,2...) increase and accordingly as the "Orange".
Okay. After splitting it, Lets assume I have stored the first two data(Apple, Orange) in a variable(in setter) to return the same in the getter function. And now I want to add the value(1234,1244....etc) in the 'orange' thing into a variable to return it later. Before that i have to check how many oranges have come. For that, i know i have to use for loop. But don't know how to store the "Value" into a variable.
Please Help me guys.

String input = "Apple;Mango;Orange:1234;Orange:1244;...;"
String values[] = input.split(";");
String value1 = values[0];
String value2 = values[1];
Hashmap< String, ArrayList<String> > map = new HashMap<String, ArrayList<String>>();
for(int i = 2; i < values.length; i = i + 2){
String key = values[i];
String id = values[i+1];
if (map.get(key) == null){
map.put(key, new ArrayList<String>());
}
map.get(key).add(id);
}
//for any key s:
// get the values of s
map.get(s); // returns a list of all values added
// get the count of s
map.get(s).size(); // return the total number of values.

Let me try to rephrase the question by how I interpreted it and -- more importantly -- how it focuses on the input and output (expectations), not the actual implementation:
I need to parse the string
"Apple;Mango;Orange:1234;Orange:1244;...;"
in a way so I can retrieve the values associated (numbers after ':') with the fruits:
I should receive an empty list for both the Apple and Mango in the example, because they have no value;
I should receive a list of 1234, 1244 for Orange.
Of course your intuition of HashMap is right on the spot, but someone may always present a better solution if you don't get too involved with the specifics.
There are a few white spots left:
Should the fruits without values have a default value given?
Should the fruits without values be in the map at all?
How input errors should be handled?
How duplicate values should be handled?
Given this context, we can start writing code:
import java.util.*;
public class FruitMarker {
public static void main(String[] args) {
String input = "Apple;Mango;Orange:1234;Orange:1244";
// replace with parameter processing from 'args'
// avoid direct implementations in variable definitions
// also observe the naming referring to the function of the variable
Map<String, Collection<Integer>> fruitIds = new HashMap<String, Collection<Integer>>();
// iterate through items by splitting
for (String item : input.split(";")) {
String[] fruitAndId = item.split(":"); // this will return the same item in an array, if separator is not found
String fruitName = fruitAndId[0];
boolean hasValue = fruitAndId.length > 1;
Collection<Integer> values = fruitIds.get(fruitName);
// if we are accessing the key for the first time, we have to set its value
if (values == null) {
values = new ArrayList<Integer>(); // here I can use concrete implementation
fruitIds.put(fruitName, values); // be sure to put it back in the map
}
if (hasValue) {
int fruitValue = Integer.parseInt(fruitAndId[1]);
values.add(fruitValue);
}
}
// display the entries in table iteratively
for (Map.Entry<String, Collection<Integer>> entry : fruitIds.entrySet()) {
System.out.println(entry.getKey() + " => " + entry.getValue());
}
}
}
If you execute this code, you will get the following output:
Mango => []
Apple => []
Orange => [1234, 1244]