I think apache provides a better util class which provides a function to get the string

ReflectionToStringBuilder.toString(object) 

Every class in Java has the toString() method in it by default, which is called if you pass some object of that class to System.out.println(). By default, this call returns the className@hashcode of that object.

{ SomeClass sc = new SomeClass(); // Class @ followed by hashcode of object in Hexadecimal System.out.println(sc); } 

You can override the toString method of a class to get different output. See this example

class A { String s = "I am just a object"; @Override public String toString() { return s; } } class B { public static void main(String args[]) { A obj = new A(); System.out.println(obj); } } 

In Eclipse, Go to your class, Right click->source->Generate toString();

It will override the toString() method and will print the object of that class.

I prefer to use a utility function which uses GSON to de-serialize the Java object into JSON string.

/** * This class provides basic/common functionalities to be applied on Java Objects. */ public final class ObjectUtils { private static final Gson GSON = new GsonBuilder().setPrettyPrinting().create(); private ObjectUtils() { throw new UnsupportedOperationException("Instantiation of this class is not permitted in case you are using reflection."); } /** * This method is responsible for de-serializing the Java Object into Json String. * * @param object Object to be de-serialized. * @return String */ public static String deserializeObjectToString(final Object object) { return GSON.toJson(object); } } 

By default, every Object in Java has the toString() method which outputs the ObjectType@HashCode.

If you want more meaningfull information then you need to override the toString() method in your class.

public class Person { private String name; // constructor and getter/setter omitted // overridding toString() to print name public String toString(){ return name; } } 

Now when you print the person object using System.out.prtinln(personObj); it will print the name of the person instead of the classname and hashcode.

In your second case when you are trying to print the array, it prints [Lcom.foo.Person;@28a418fc the Array type and it's hashcode.

If you want to print the person names, there are many ways.

You could write your own function that iterates each person and prints

void printPersonArray(Person[] persons){ for(Person person: persons){ System.out.println(person); } } 

You could print it using Arrays.toString(). This seems the simplest to me.

 System.out.println(Arrays.toString(persons)); System.out.println(Arrays.deepToString(persons)); // for nested arrays 

You could print it the java 8 way (using streams and method reference).

 Arrays.stream(persons).forEach(System.out::println); 

There might be other ways as well. Hope this helps. :)

In intellij you can auto generate toString method by pressing alt+inset and then selecting toString() here is an out put for a test class:

public class test { int a; char b; String c; Test2 test2; @Override public String toString() { return "test{" + "a=" + a + ", b=" + b + ", c='" + c + '\'' + ", test2=" + test2 + '}'; } } 

As you can see, it generates a String by concatenating, several attributes of the class, for primitives it will print their values and for reference types it will use their class type (in this case to string method of Test2).

If you Directly print any object of Person It will the ClassName@HashCode to the Code.

in your case com.foo.Person@2f92e0f4 is getting printed . Where Person is a class to which object belongs and 2f92e0f4 is hashCode of the Object.

public class Person { private String name; public Person(String name){ this.name = name; } // getter/setter omitted @override public String toString(){ return name; } } 

Now if you try to Use the object of Person then it will print the name

Class Test { public static void main(String... args){ Person obj = new Person("YourName"); System.out.println(obj.toString()); } } 

For a "deep" toString() there is an alternative to the JSON based answers (Jackson, GSON, etc.): ReflectionToStringBuilder from the Apache Commons Lang 3 library, with RecursiveToStringStyle or MultilineRecursiveToStringStyle. Code example:

System.out.println("My object: " + ReflectionToStringBuilder .toString(theObject, new RecursiveToStringStyle())); // or as "toString()" overrides @Override public String toString() { return ReflectionToStringBuilder .toString(this, new RecursiveToStringStyle()); } // or @Override public String toString() { return ReflectionToStringBuilder .toString(this, new MultilineRecursiveToStringStyle()); } 

Output examples:

// RecursiveToStringStyle Person@7f54[name=Stephen,age=29,smoker=false,job=Job@43cd2[title=Manager]] // MultilineRecursiveToStringStyle Person@7f54[ name=Stephen, age=29, smoker=false, job=Job@43cd2[ title=Manager ] ] 

If you look at the Object class (Parent class of all classes in Java) the toString() method implementation is

 public String toString() { return getClass().getName() + "@" + Integer.toHexString(hashCode()); } 

whenever you print any object in Java then toString() will be call. Now it's up to you if you override toString() then your method will call other Object class method call.

Using Lombok @Data annotation on class will provide getter, setter, toString and hashcode. Using Lombok is better as it handles boilerplate code.

I managed to get this done using Jackson in Spring 5. Depending on the object it might not work in all cases.

import com.fasterxml.jackson.databind.ObjectMapper; ObjectMapper mapper = new ObjectMapper(); System.out.println(mapper.writeValueAsString(yourObject)); 

The output would look like:

{ "id" : 1, "fieldOne" : "string" } 

Here are more examples using Jackson.

If you use GSON instead It might look like:

Gson gson = new Gson(); System.out.println(gson.toJson(yourObject)); 

If you are using project Lombok you could use the @ToString annotation and generate a standard toString() method without adding boilerplate.

import lombok.ToString; @ToString public class LoginDto { private String user; private String pass; } 

... System.out.println(loginDto.toString()); // LoginDto([email protected], pass=xxxxx) 

If you don't want to Override the toString() method you can use this,

 public static void printJson(Object o) { ObjectMapper mapper = new ObjectMapper(); try { String json = mapper.writerWithDefaultPrettyPrinter().writeValueAsString(o); System.out.println(json); } catch (Exception e) { e.printStackTrace(); } } 

We also need to import, import com.fasterxml.jackson.databind.ObjectMapper;

We can make a Utils method and it will be very handy.

Just use the @ToString from Lombok project gets the job done

There are 2 good ways to do it

1. object.toString() - The default implementation of toString() in the Object class returns a string consisting of the class name, the @ character, and the unsigned hexadecimal representation of the hash code of the object. For example, com.example.MyClass@1a2b3c4d.

It's a common practice to override the toString() method in classes to provide a string representation of the object's state.

Implementation

public class MyClass { private int id; private String name; @Override public String toString() { return "MyClass{id=" + id + ", name='" + name + "'}"; } } 

Output: MyClass{id=1, name='Test'}

2. ReflectionToStringBuilder.toString(object) - The ReflectionToStringBuilder from the Apache Commons Lang library uses reflection to automatically generate a string representation of all fields of an object, including inherited fields from superclasses. It provides a quick way to implement a comprehensive toString() method without manually writing the code for each field.

Implementation

import org.apache.commons.lang3.builder.ReflectionToStringBuilder; public class MyClass { private int id; private String name; @Override public String toString() { return ReflectionToStringBuilder.toString(this); } } 

Output: com.example.MyClass@1a2b3c4d[id=1,name=Test]