public final class

Join

extends Object
java.lang.Object
   ↳ com.google.gdata.util.common.base.Join

Class Overview

Utility for joining pieces of text separated by a delimiter. It can handle iterators, collections, arrays, and varargs, and can append to any Appendable or just return a String. For example, join(":", "a", "b", "c") returns "a:b:c".

All methods of this class throw NullPointerException when a value of null is supplied for any parameter. The elements within the collection, iterator, array, or varargs parameter list may be null -- these will be represented in the output by the string "null".

Summary

Nested Classes
class Join.JoinException Exception thrown in response to an IOException from the supplied Appendable. 
Public Methods
static <T extends Appendable> T join(T appendable, String delimiter, Iterator<?> tokens)
Appends each of the tokens to appendable, separated by delimiter.
static String join(String delimiter, Object[] tokens)
Returns a string containing the tokens, converted to strings if necessary, separated by delimiter.
static String join(String keyValueSeparator, String entryDelimiter, Map<?, ?> map)
Returns a string containing the contents of map, with entries separated by entryDelimiter, and keys and values separated with keyValueSeparator.
static <T extends Appendable> T join(T appendable, String keyValueSeparator, String entryDelimiter, Map<?, ?> map)
Appends the contents of map to appendable, with entries separated by entryDelimiter, and keys and values separated with keyValueSeparator.
static <T extends Appendable> T join(T appendable, String delimiter, Object[] tokens)
Appends each of the tokens to appendable, separated by delimiter.
static <T extends Appendable> T join(T appendable, String delimiter, Iterable<?> tokens)
Appends each of the tokens to appendable, separated by delimiter.
static String join(String delimiter, Iterator<?> tokens)
Returns a string containing the tokens, converted to strings if necessary, separated by delimiter.
static String join(String delimiter, Iterable<?> tokens)
Returns a string containing the tokens, converted to strings if necessary, separated by delimiter.
static <T extends Appendable> T join(T appendable, String delimiter, Object firstToken, Object... otherTokens)
Appends each of the tokens to appendable, separated by delimiter.
static String join(String delimiter, Object firstToken, Object... otherTokens)
Returns a string containing the tokens, converted to strings if necessary, separated by delimiter.
[Expand]
Inherited Methods
From class java.lang.Object

Public Methods

public static T join (T appendable, String delimiter, Iterator<?> tokens)

Appends each of the tokens to appendable, separated by delimiter.

Each token will be converted to a CharSequence using valueOf(Object), if it isn't a CharSequence already. Note that this implies that null tokens will be appended as the four-character string "null".

Parameters
appendable The object to append the results to
delimiter A string to append between every element, but not at the beginning or end
tokens Objects to append
Returns
  • the same Appendable instance that was passed in
Throws
Join.JoinException if an IOException occurs

public static String join (String delimiter, Object[] tokens)

Returns a string containing the tokens, converted to strings if necessary, separated by delimiter. If tokens is empty, it returns an empty string.

Each token will be converted to a CharSequence using valueOf(Object), if it isn't a CharSequence already. Note that this implies that null tokens will be appended as the four-character string "null".

Parameters
delimiter A string to append between every element, but not at the beginning or end
tokens Objects to append
Returns
  • a string consisting of the joined elements

public static String join (String keyValueSeparator, String entryDelimiter, Map<?, ?> map)

Returns a string containing the contents of map, with entries separated by entryDelimiter, and keys and values separated with keyValueSeparator.

Each key and value will be converted to a CharSequence using valueOf(Object), if it isn't a CharSequence already. Note that this implies that null tokens will be appended as the four-character string "null".

Parameters
keyValueSeparator A string to append between every key and its associated value
entryDelimiter A string to append between every entry, but not at the beginning or end
map The map containing the data to join
Returns
  • a string consisting of the joined entries of the map; empty if the map is empty

public static T join (T appendable, String keyValueSeparator, String entryDelimiter, Map<?, ?> map)

Appends the contents of map to appendable, with entries separated by entryDelimiter, and keys and values separated with keyValueSeparator.

Each key and value will be converted to a CharSequence using valueOf(Object), if it isn't a CharSequence already. Note that this implies that null tokens will be appended as the four-character string "null".

Parameters
appendable The object to append the results to
keyValueSeparator A string to append between every key and its associated value
entryDelimiter A string to append between every entry, but not at the beginning or end
map The map containing the data to join
Returns
  • the same Appendable instance that was passed in

public static T join (T appendable, String delimiter, Object[] tokens)

Appends each of the tokens to appendable, separated by delimiter.

Each token will be converted to a CharSequence using valueOf(Object), if it isn't a CharSequence already. Note that this implies that null tokens will be appended as the four-character string "null".

Parameters
appendable The object to append the results to
delimiter A string to append between every element, but not at the beginning or end
tokens Objects to append
Returns
  • the same Appendable instance that was passed in
Throws
Join.JoinException if an IOException occurs

public static T join (T appendable, String delimiter, Iterable<?> tokens)

Appends each of the tokens to appendable, separated by delimiter.

Each token will be converted to a CharSequence using valueOf(Object), if it isn't a CharSequence already. Note that this implies that null tokens will be appended as the four-character string "null".

Parameters
appendable The object to append the results to
delimiter A string to append between every element, but not at the beginning or end
tokens Objects to append
Returns
  • the same Appendable instance that was passed in
Throws
Join.JoinException if an IOException occurs

public static String join (String delimiter, Iterator<?> tokens)

Returns a string containing the tokens, converted to strings if necessary, separated by delimiter. If tokens is empty, it returns an empty string.

Each token will be converted to a CharSequence using valueOf(Object), if it isn't a CharSequence already. Note that this implies that null tokens will be appended as the four-character string "null".

Parameters
delimiter A string to append between every element, but not at the beginning or end
tokens Objects to append
Returns
  • a string consisting of the joined elements

public static String join (String delimiter, Iterable<?> tokens)

Returns a string containing the tokens, converted to strings if necessary, separated by delimiter. If tokens is empty, it returns an empty string.

Each token will be converted to a CharSequence using valueOf(Object), if it isn't a CharSequence already. Note that this implies that null tokens will be appended as the four-character string "null".

Parameters
delimiter A string to append between every element, but not at the beginning or end
tokens Objects to append
Returns
  • a string consisting of the joined elements

public static T join (T appendable, String delimiter, Object firstToken, Object... otherTokens)

Appends each of the tokens to appendable, separated by delimiter.

Each token will be converted to a CharSequence using valueOf(Object), if it isn't a CharSequence already. Note that this implies that null tokens will be appended as the four-character string "null".

Parameters
appendable The object to append the results to
delimiter A string to append between every element, but not at the beginning or end
firstToken The first object to append
otherTokens Subsequent objects to append
Returns
  • the same Appendable instance that was passed in
Throws
Join.JoinException if an IOException occurs

public static String join (String delimiter, Object firstToken, Object... otherTokens)

Returns a string containing the tokens, converted to strings if necessary, separated by delimiter.

Each token will be converted to a CharSequence using valueOf(Object), if it isn't a CharSequence already. Note that this implies that null tokens will be appended as the four-character string "null".

Parameters
delimiter A string to append between every element, but not at the beginning or end
firstToken The first object to append
otherTokens Subsequent objects to append
Returns
  • a string consisting of the joined elements