Question

I have a map object testMap declared as HashMap<String, Test>.

Test is a simple class which contains references to an Object and to two String values.

ie,

public class Test {

  private String name;
  private String id;
  private Object val;


public Test(Object val,String name.String id){
  this.val =val;
  this.id=id;
  this.name = name;
}

I want to update the “name” only in the Hash map “testMap.” How can I do this?

Answer 1

You need to change the visibility of your name property to public or add a setter to it:

public class Test {

  private String name;
  private String id;
  private Object val;


public Test(Object val,String name, String id){
  this.val =val;
  this.id = id;
  this.name = name;
}

public void setName(String name) {
  this.name = name;
}

Then, to change your name, you need to

Test test = testMap.get("key");
if (test != null) {
   test.setName("new name");
}

If you want to update the Map key also, then you need

Test test = testMap.remove("oldKey");
if (test != null) {
   test.setName("newKey");
   test.put("newKey", test);
}