Uses of Class java.lang.StringBuffer (Java Platform SE 8 )
Date: 2026-03-16

## Uses of Class
java.lang.StringBuffer

- Packages that use StringBuffer
  Package | Description
  --- | ---
  java.io | Provides for system input and output through data streams, serialization and the file system.
  java.lang | Provides classes that are fundamental to the design of the Java programming language.
  java.text | Provides classes and interfaces for handling text, dates, numbers, and messages in a manner independent of natural languages.
  java.util.regex | Classes for matching character sequences against patterns specified by regular expressions.
  javax.swing.text.html.parser | Provides the default HTML parser, along with support classes.

- - ### Uses of StringBuffer in java.io

    Methods in java.io that return StringBuffer
    Modifier and Type | Method and Description
    --- | ---
    `StringBuffer` | StringWriter.`getBuffer()` Return the string buffer itself.

  - ### Uses of StringBuffer in java.lang

    Methods in java.lang that return StringBuffer
    Modifier and Type | Method and Description
    --- | ---
    `StringBuffer` | StringBuffer.`append(boolean b)`
    `StringBuffer` | StringBuffer.`append(char c)`
    `StringBuffer` | StringBuffer.`append(char[] str)`
    `StringBuffer` | StringBuffer.`append(char[] str, int offset, int len)`
    `StringBuffer` | StringBuffer.`append(CharSequence s)` Appends the specified `CharSequence` to this sequence.
    `StringBuffer` | StringBuffer.`append(CharSequence s, int start, int end)`
    `StringBuffer` | StringBuffer.`append(double d)`
    `StringBuffer` | StringBuffer.`append(float f)`
    `StringBuffer` | StringBuffer.`append(int i)`
    `StringBuffer` | StringBuffer.`append(long lng)`
    `StringBuffer` | StringBuffer.`append(Object obj)`
    `StringBuffer` | StringBuffer.`append(String str)`
    `StringBuffer` | StringBuffer.`append(StringBuffer sb)` Appends the specified `StringBuffer` to this sequence.
    `StringBuffer` | StringBuffer.`appendCodePoint(int codePoint)`
    `StringBuffer` | StringBuffer.`delete(int start, int end)`
    `StringBuffer` | StringBuffer.`deleteCharAt(int index)`
    `StringBuffer` | StringBuffer.`insert(int offset, boolean b)`
    `StringBuffer` | StringBuffer.`insert(int offset, char c)`
    `StringBuffer` | StringBuffer.`insert(int offset, char[] str)`
    `StringBuffer` | StringBuffer.`insert(int index, char[] str, int offset, int len)`
    `StringBuffer` | StringBuffer.`insert(int dstOffset, CharSequence s)`
    `StringBuffer` | StringBuffer.`insert(int dstOffset, CharSequence s, int start, int end)`
    `StringBuffer` | StringBuffer.`insert(int offset, double d)`
    `StringBuffer` | StringBuffer.`insert(int offset, float f)`
    `StringBuffer` | StringBuffer.`insert(int offset, int i)`
    `StringBuffer` | StringBuffer.`insert(int offset, long l)`
    `StringBuffer` | StringBuffer.`insert(int offset, Object obj)`
    `StringBuffer` | StringBuffer.`insert(int offset, String str)`
    `StringBuffer` | StringBuffer.`replace(int start, int end, String str)`
    `StringBuffer` | StringBuffer.`reverse()`

    Methods in java.lang with parameters of type StringBuffer
    Modifier and Type | Method and Description
    --- | ---
    `StringBuffer` | StringBuffer.`append(StringBuffer sb)` Appends the specified `StringBuffer` to this sequence.
    `StringBuilder` | StringBuilder.`append(StringBuffer sb)` Appends the specified `StringBuffer` to this sequence.
    `boolean` | String.`contentEquals(StringBuffer sb)` Compares this string to the specified `StringBuffer`.

    Constructors in java.lang with parameters of type StringBuffer
    Constructor and Description
    `String(StringBuffer buffer)` Allocates a new string that contains the sequence of characters currently contained in the string buffer argument.

  - ### Uses of StringBuffer in java.text

    Methods in java.text that return StringBuffer
    Modifier and Type | Method and Description
    --- | ---
    `StringBuffer` | SimpleDateFormat.`format(Date date, StringBuffer toAppendTo, FieldPosition pos)` Formats the given `Date` into a date/time string and appends the result to the given `StringBuffer`.
    `abstract StringBuffer` | DateFormat.`format(Date date, StringBuffer toAppendTo, FieldPosition fieldPosition)` Formats a Date into a date/time string.
    `StringBuffer` | ChoiceFormat.`format(double number, StringBuffer toAppendTo, FieldPosition status)` Returns pattern with formatted double.
    `StringBuffer` | DecimalFormat.`format(double number, StringBuffer result, FieldPosition fieldPosition)` Formats a double to produce a string.
    `abstract StringBuffer` | NumberFormat.`format(double number, StringBuffer toAppendTo, FieldPosition pos)` Specialization of format.
    `StringBuffer` | ChoiceFormat.`format(long number, StringBuffer toAppendTo, FieldPosition status)` Specialization of format.
    `StringBuffer` | DecimalFormat.`format(long number, StringBuffer result, FieldPosition fieldPosition)` Format a long to produce a string.
    `abstract StringBuffer` | NumberFormat.`format(long number, StringBuffer toAppendTo, FieldPosition pos)` Specialization of format.
    `StringBuffer` | MessageFormat.`format(Object[] arguments, StringBuffer result, FieldPosition pos)` Formats an array of objects and appends the `MessageFormat`'s pattern, with format elements replaced by the formatted objects, to the provided `StringBuffer`.
    `StringBuffer` | DecimalFormat.`format(Object number, StringBuffer toAppendTo, FieldPosition pos)` Formats a number and appends the resulting text to the given string buffer.
    `StringBuffer` | DateFormat.`format(Object obj, StringBuffer toAppendTo, FieldPosition fieldPosition)` Overrides Format.
    `abstract StringBuffer` | Format.`format(Object obj, StringBuffer toAppendTo, FieldPosition pos)` Formats an object and appends the resulting text to a given string buffer.
    `StringBuffer` | NumberFormat.`format(Object number, StringBuffer toAppendTo, FieldPosition pos)` Formats a number and appends the resulting text to the given string buffer.
    `StringBuffer` | MessageFormat.`format(Object arguments, StringBuffer result, FieldPosition pos)` Formats an array of objects and appends the `MessageFormat`'s pattern, with format elements replaced by the formatted objects, to the provided `StringBuffer`.

    Methods in java.text with parameters of type StringBuffer
    Modifier and Type | Method and Description
    --- | ---
    `StringBuffer` | SimpleDateFormat.`format(Date date, StringBuffer toAppendTo, FieldPosition pos)` Formats the given `Date` into a date/time string and appends the result to the given `StringBuffer`.
    `abstract StringBuffer` | DateFormat.`format(Date date, StringBuffer toAppendTo, FieldPosition fieldPosition)` Formats a Date into a date/time string.
    `StringBuffer` | ChoiceFormat.`format(double number, StringBuffer toAppendTo, FieldPosition status)` Returns pattern with formatted double.
    `StringBuffer` | DecimalFormat.`format(double number, StringBuffer result, FieldPosition fieldPosition)` Formats a double to produce a string.
    `abstract StringBuffer` | NumberFormat.`format(double number, StringBuffer toAppendTo, FieldPosition pos)` Specialization of format.
    `StringBuffer` | ChoiceFormat.`format(long number, StringBuffer toAppendTo, FieldPosition status)` Specialization of format.
    `StringBuffer` | DecimalFormat.`format(long number, StringBuffer result, FieldPosition fieldPosition)` Format a long to produce a string.
    `abstract StringBuffer` | NumberFormat.`format(long number, StringBuffer toAppendTo, FieldPosition pos)` Specialization of format.
    `StringBuffer` | MessageFormat.`format(Object[] arguments, StringBuffer result, FieldPosition pos)` Formats an array of objects and appends the `MessageFormat`'s pattern, with format elements replaced by the formatted objects, to the provided `StringBuffer`.
    `StringBuffer` | DecimalFormat.`format(Object number, StringBuffer toAppendTo, FieldPosition pos)` Formats a number and appends the resulting text to the given string buffer.
    `StringBuffer` | DateFormat.`format(Object obj, StringBuffer toAppendTo, FieldPosition fieldPosition)` Overrides Format.
    `abstract StringBuffer` | Format.`format(Object obj, StringBuffer toAppendTo, FieldPosition pos)` Formats an object and appends the resulting text to a given string buffer.
    `StringBuffer` | NumberFormat.`format(Object number, StringBuffer toAppendTo, FieldPosition pos)` Formats a number and appends the resulting text to the given string buffer.
    `StringBuffer` | MessageFormat.`format(Object arguments, StringBuffer result, FieldPosition pos)` Formats an array of objects and appends the `MessageFormat`'s pattern, with format elements replaced by the formatted objects, to the provided `StringBuffer`.

  - ### Uses of StringBuffer in java.util.regex

    Methods in java.util.regex that return StringBuffer
    Modifier and Type | Method and Description
    --- | ---
    `StringBuffer` | Matcher.`appendTail(StringBuffer sb)` Implements a terminal append-and-replace step.

    Methods in java.util.regex with parameters of type StringBuffer
    Modifier and Type | Method and Description
    --- | ---
    `Matcher` | Matcher.`appendReplacement(StringBuffer sb, String replacement)` Implements a non-terminal append-and-replace step.
    `StringBuffer` | Matcher.`appendTail(StringBuffer sb)` Implements a terminal append-and-replace step.

  - ### Uses of StringBuffer in javax.swing.text.html.parser

    Methods in javax.swing.text.html.parser with parameters of type StringBuffer
    Modifier and Type | Method and Description
    --- | ---
    `protected boolean` | Parser.`parseMarkupDeclarations(StringBuffer strBuff)` Parse markup declarations.

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