Java StringBuilder Methods

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The StringBuilder class in Java is a mutable sequence of characters. It is used to create and manipulate strings that can be modified after they are created. This is in contrast to the String class, whose instances are immutable. Understanding the methods provided by the StringBuilder class is essential for efficient string manipulation.

This guide covers various methods available in the StringBuilder class, offering a comprehensive understanding of how to append, insert, replace, and delete characters within a string. These methods are essential for efficient coding practices and help in performing various operations on strings.

For more detailed information, you can refer to the official Java SE Documentation and additional resources on the Java String API Guide.

Method Description
append() Appends the specified string to this character sequence.
capacity() Returns the current capacity of the StringBuilder.
charAt() Returns the character at the specified index.
chars() Returns a stream of int values representing the characters in this sequence.
codePointAt() Returns the Unicode code point at the specified index.
codePointBefore() Returns the Unicode code point before the specified index.
codePointCount() Returns the number of Unicode code points in the specified text range.
codePoints() Returns a stream of int values representing the Unicode code points in this sequence.
delete() Removes the characters in a substring of this sequence.
deleteCharAt() Removes the character at the specified position in this sequence.
ensureCapacity() Ensures that the capacity is at least equal to the specified minimum.
getChars() Copies characters from this sequence into the destination character array.
indexOf() Returns the index within this sequence of the first occurrence of the specified substring.
insert() Inserts the string representation of the given data at the specified position.
lastIndexOf() Returns the index within this sequence of the last occurrence of the specified substring.
length() Returns the length (character count) of this sequence.
repeat() Returns a string whose value is the concatenation of this sequence repeated the specified number of times.
replace() Replaces the characters in a substring of this sequence with characters in the specified string.
reverse() Reverses the sequence of characters in this sequence.
setLength() Sets the length of this sequence.
subSequence() Returns a new character sequence that is a subsequence of this sequence.
substring() Returns a new string that is a substring of this sequence.
trimToSize() Attempts to reduce storage used for the character sequence.
toString() Returns a string representing the data in this sequence.

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