org.apache.http.message
Class BasicHeaderValueFormatter

java.lang.Object
  org.apache.http.message.BasicHeaderValueFormatter

All Implemented Interfaces:

HeaderValueFormatter

@Contract(threading=IMMUTABLE)
public class BasicHeaderValueFormatter
extends Object
implements HeaderValueFormatter

Basic implementation for formatting header value elements. Instances of this class are stateless and thread-safe. Derived classes are expected to maintain these properties.

Since:

4.0

Field Summary

static BasicHeaderValueFormatter	DEFAULT Deprecated. (4.3) use INSTANCE
static BasicHeaderValueFormatter	INSTANCE
static String	SEPARATORS Special characters that can be used as separators in HTTP parameters.
static String	UNSAFE_CHARS Unsafe special characters that must be escaped using the backslash character

Constructor Summary

BasicHeaderValueFormatter()

Method Summary

protected void	doFormatValue(CharArrayBuffer buffer, String value, boolean quote) Actually formats the value of a name-value pair.
protected int	estimateElementsLen(HeaderElement[] elems) Estimates the length of formatted header elements.
protected int	estimateHeaderElementLen(HeaderElement elem) Estimates the length of a formatted header element.
protected int	estimateNameValuePairLen(NameValuePair nvp) Estimates the length of a formatted name-value pair.
protected int	estimateParametersLen(NameValuePair[] nvps) Estimates the length of formatted parameters.
CharArrayBuffer	formatElements(CharArrayBuffer charBuffer, HeaderElement[] elems, boolean quote) Formats an array of header elements.
static String	formatElements(HeaderElement[] elems, boolean quote, HeaderValueFormatter formatter) Formats an array of header elements.
CharArrayBuffer	formatHeaderElement(CharArrayBuffer charBuffer, HeaderElement elem, boolean quote) Formats one header element.
static String	formatHeaderElement(HeaderElement elem, boolean quote, HeaderValueFormatter formatter) Formats a header element.
CharArrayBuffer	formatNameValuePair(CharArrayBuffer charBuffer, NameValuePair nvp, boolean quote) Formats one name-value pair, where the value is optional.
static String	formatNameValuePair(NameValuePair nvp, boolean quote, HeaderValueFormatter formatter) Formats a name-value pair.
CharArrayBuffer	formatParameters(CharArrayBuffer charBuffer, NameValuePair[] nvps, boolean quote) Formats the parameters of a header element.
static String	formatParameters(NameValuePair[] nvps, boolean quote, HeaderValueFormatter formatter) Formats a set of parameters.
protected boolean	isSeparator(char ch) Checks whether a character is a separator.
protected boolean	isUnsafe(char ch) Checks whether a character is unsafe.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

DEFAULT

@Deprecated
public static final BasicHeaderValueFormatter DEFAULT

Deprecated. (4.3) use INSTANCE

A default instance of this class, for use as default or fallback. Note that BasicHeaderValueFormatter is not a singleton, there can be many instances of the class itself and of derived classes. The instance here provides non-customized, default behavior.

INSTANCE

public static final BasicHeaderValueFormatter INSTANCE

SEPARATORS

public static final String SEPARATORS

Special characters that can be used as separators in HTTP parameters. These special characters MUST be in a quoted string to be used within a parameter value .

See Also:

Constant Field Values

UNSAFE_CHARS

public static final String UNSAFE_CHARS

Unsafe special characters that must be escaped using the backslash character

See Also:

Constant Field Values

Constructor Detail

BasicHeaderValueFormatter

public BasicHeaderValueFormatter()

Method Detail

formatElements

public static String formatElements(HeaderElement[] elems,
                                    boolean quote,
                                    HeaderValueFormatter formatter)

Formats an array of header elements.

Parameters:

elems - the header elements to format

quote - true to always format with quoted values, false to use quotes only when necessary

formatter - the formatter to use, or null for the default

Returns:

the formatted header elements

formatElements

public CharArrayBuffer formatElements(CharArrayBuffer charBuffer,
                                      HeaderElement[] elems,
                                      boolean quote)

Description copied from interface: HeaderValueFormatter

Formats an array of header elements.

Specified by:

formatElements in interface HeaderValueFormatter

Parameters:

charBuffer - the buffer to append to, or null to create a new buffer

elems - the header elements to format

quote - true to always format with quoted values, false to use quotes only when necessary

Returns:

a buffer with the formatted header elements. If the buffer argument was not null, that buffer will be used and returned.

estimateElementsLen

protected int estimateElementsLen(HeaderElement[] elems)

Estimates the length of formatted header elements.

Parameters:

elems - the header elements to format, or null

Returns:

a length estimate, in number of characters

formatHeaderElement

public static String formatHeaderElement(HeaderElement elem,
                                         boolean quote,
                                         HeaderValueFormatter formatter)

Formats a header element.

Parameters:

elem - the header element to format

quote - true to always format with quoted values, false to use quotes only when necessary

formatter - the formatter to use, or null for the default

Returns:

the formatted header element

formatHeaderElement

public CharArrayBuffer formatHeaderElement(CharArrayBuffer charBuffer,
                                           HeaderElement elem,
                                           boolean quote)

Description copied from interface: HeaderValueFormatter

Formats one header element.

Specified by:

formatHeaderElement in interface HeaderValueFormatter

Parameters:

charBuffer - the buffer to append to, or null to create a new buffer

elem - the header element to format

quote - true to always format with quoted values, false to use quotes only when necessary

Returns:

a buffer with the formatted header element. If the buffer argument was not null, that buffer will be used and returned.

estimateHeaderElementLen

protected int estimateHeaderElementLen(HeaderElement elem)

Estimates the length of a formatted header element.

Parameters:

elem - the header element to format, or null

Returns:

a length estimate, in number of characters

formatParameters

public static String formatParameters(NameValuePair[] nvps,
                                      boolean quote,
                                      HeaderValueFormatter formatter)

Formats a set of parameters.

Parameters:

nvps - the parameters to format

quote - true to always format with quoted values, false to use quotes only when necessary

formatter - the formatter to use, or null for the default

Returns:

the formatted parameters

formatParameters

public CharArrayBuffer formatParameters(CharArrayBuffer charBuffer,
                                        NameValuePair[] nvps,
                                        boolean quote)

Description copied from interface: HeaderValueFormatter

Formats the parameters of a header element. That's a list of name-value pairs, to be separated by semicolons. This method will not generate a leading semicolon.

Specified by:

formatParameters in interface HeaderValueFormatter

Parameters:

charBuffer - the buffer to append to, or null to create a new buffer

nvps - the parameters (name-value pairs) to format

quote - true to always format with quoted values, false to use quotes only when necessary

Returns:

a buffer with the formatted parameters. If the buffer argument was not null, that buffer will be used and returned.

estimateParametersLen

protected int estimateParametersLen(NameValuePair[] nvps)

Estimates the length of formatted parameters.

Parameters:

nvps - the parameters to format, or null

Returns:

a length estimate, in number of characters

formatNameValuePair

public static String formatNameValuePair(NameValuePair nvp,
                                         boolean quote,
                                         HeaderValueFormatter formatter)

Formats a name-value pair.

Parameters:

nvp - the name-value pair to format

quote - true to always format with a quoted value, false to use quotes only when necessary

formatter - the formatter to use, or null for the default

Returns:

the formatted name-value pair

formatNameValuePair

public CharArrayBuffer formatNameValuePair(CharArrayBuffer charBuffer,
                                           NameValuePair nvp,
                                           boolean quote)

Description copied from interface: HeaderValueFormatter

Formats one name-value pair, where the value is optional.

Specified by:

formatNameValuePair in interface HeaderValueFormatter

Parameters:

charBuffer - the buffer to append to, or null to create a new buffer

nvp - the name-value pair to format

quote - true to always format with a quoted value, false to use quotes only when necessary

Returns:

a buffer with the formatted name-value pair. If the buffer argument was not null, that buffer will be used and returned.

estimateNameValuePairLen

protected int estimateNameValuePairLen(NameValuePair nvp)

Estimates the length of a formatted name-value pair.

Parameters:

nvp - the name-value pair to format, or null

Returns:

a length estimate, in number of characters

doFormatValue

protected void doFormatValue(CharArrayBuffer buffer,
                             String value,
                             boolean quote)

Actually formats the value of a name-value pair. This does not include a leading = character. Called from formatNameValuePair.

Parameters:

buffer - the buffer to append to, never null

value - the value to append, never null

quote - true to always format with quotes, false to use quotes only when necessary

isSeparator

protected boolean isSeparator(char ch)

Checks whether a character is a separator.

Parameters:

ch - the character to check

Returns:

true if the character is a separator, false otherwise

isUnsafe

protected boolean isUnsafe(char ch)

Checks whether a character is unsafe.

Parameters:

ch - the character to check

Returns:

true if the character is unsafe, false otherwise