The substring() method in Java, when invoked with a single parameter, allows for the extraction of a new String object starting from the specified startIndex (inclusive) and extending to the end of the original String, encompassing the last character of the String. This variant extracts the characters between the starting and ending indices from the original String.

This variant extracts the portion of the String starting from the specified index to the end of the String.Īnother version of the substring() method takes two parameters, denoting the starting index and the ending index (exclusive) of the desired substring. One version takes a single parameter, representing the starting index of the substring. The substring() method in Java offers flexibility by accepting different variations of parameters. There are two ways you can use the Java substring() method This new String object is created based on the original String and contains the characters specified by the substring parameters. When the substring() method is invoked, it returns a brand new String object that represents the extracted substring. In Java, the String class provides a substring() method that facilitates the extraction of a specific substring from a given String. The substring refers to a portion or fragment extracted from a larger String. This is pretty technical but will make more sense when you start to work with Strings more and more.The concept of substrings holds significance when dealing with Strings. the reference will refer to the object in the heap. You create two string objects: one in the pool and the other in the heap. Will only create a String object in the pool and the reference s will refer to it, but by using In Java String objects are immutable (i.e their values cannot be changed once they are initialized), so when editing a string object you end up creating a new edited string object wherease the old object just floats around in a special memory area called the 'string constant pool'. There is a 'String constant pool' in the Java language.

Then s!=t (because you've explicitly created a new string) although s.equals(t) will return true (because the equals method checks for value equality instead of reference equality). Then s and t actually refer to the same String object, and ‘s = t’ will return true, because for objects the double equal sign ('=') reads as 'is the same object'. Nor can you extend String, because it's declared as final, meaning no sub-classing is allowed (if you're not into inheritance that's ok for now). Strings are special in Java - they're immutable, and string constants (=variables that do not change) are automatically turned into String objects. You can override the standard equals() method from to implement a custom equals() method.

In general both the equals() method and “=” operator in Java are used to compare objects to check equality but the ‘’=’ operator’ checks if both objects point to the same memory location whereas the equals() method evaluates the values inside the objects.

Getting to know the String class in java took me some time. Come back to this answer later and review again. If you dont fully understand this topic right now, it's fine. This goes beyond your question but is important to realise when working with Strings in Java (and Strings are everywhere). To elaborate a little further on String equality.

Substring java not first