How to Find an Object in an Arraylist by Property

Searching in a ArrayList with custom objects for certain strings

The easy way is to make a for where you verify if the atrrtibute name of the custom object have the desired string

    for(Datapoint d : dataPointList){
        if(d.getName() != null && d.getName().contains(search))
           //something here
    }

I think this helps you.

How to search for an Object in ArrayList?

created the list and the search item:

List<String> list = new ArrayList<String>();
    list.add("book");
    list.add("pencil");
    list.add("note");

    String itemToBeSearched = "book"; // taken as example

    if(check(list,itemToBeSearched)){
        System.out.println("ITEM FOUND");
    }
    else
    {
        System.out.println("NOT FOUND");
    }

then the item check function is

public static boolean check(List<String> list, String itemToBeSearched){
    boolean isItemFound =false;
    for(String singleItem: list){
        if(singleItem.equalsIgnoreCase(itemToBeSearched)){
            isItemFound = true;
            return isItemFound;
        }
    }
    return  isItemFound;
}

and it's working for me, please try this and let us know :)

Search for a particular element from object in ArrayList

Using for loop over ArrayList can solve your problem, it's naive method and old fashioned.

Below is the code for it.

import java.util.ArrayList;

public class HelloWorld{

     public static void main(String []args){
        String author_name = "abc";
        ArrayList<book> bk = new ArrayList<book>();
        bk.add(new book("abc", "abc", "abc", 10));
        bk.add(new book("mno", "mno", "abc", 10));
        bk.add(new book("xyz", "abc", "abc", 10));
        ArrayList<book> booksByAuthor = new ArrayList<book>();
        for(book obj : bk)
        {
            if(obj.author_nm == author_name)
            {
                booksByAuthor.add(obj);
            }
        }

     }
}

class book{
      public String book_nm;
      public String author_nm;
      public String publication;
      public int price;
      public book(String book_nm,String author_nm,String publication,int price){
          this.book_nm=book_nm;
          this.author_nm=author_nm;
          this.publication=publication;
          this.price=price;
      }
}

Hope you can get an idea from it.

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