Package com.norconex.importer.util

Class CharsetUtil

java.lang.Object

com.norconex.importer.util.CharsetUtil

public final class CharsetUtil
extends Object

Character set utility methods.

Since:

2.5.0

Author:

Pascal Essiembre

Method Summary

Modifier and Type	Method	Description
static void	convertCharset(InputStream input, String inputCharset, OutputStream output, String outputCharset)	Converts the character encoding of the supplied input.
static String	convertCharset(String input, String inputCharset, String outputCharset)	Converts the character encoding of the supplied input value.
static String	detectCharset(InputStream input)	Detects the character encoding of an input stream.
static String	detectCharset(InputStream input, String declaredEncoding)	Detects the character encoding of an input stream.
static String	detectCharset(String input)	Detects the character encoding of a string.
static String	detectCharset(String input, String declaredEncoding)	Detects the character encoding of a string.
static String	detectCharsetIfBlank(String charset, Doc doc)	Detects a document character encoding if the supplied charset is blank.
static String	detectCharsetIfBlank(String charset, InputStream is)	Detects a document character encoding if the supplied charset is blank.
static String	detectsCharset(Doc doc)	Detects a document character encoding.
static String	firstNonBlankOrUTF8(ParseState parseState, String... charsets)	Returns the first non-blank character encoding, or returns UTF-8 if they are all blank or in post-parse state.
static String	firstNonBlankOrUTF8(String... charsets)	Returns the first non-blank character encoding, or returns UTF-8 if they are all blank.

Methods inherited from class java.lang.Object

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

Method Detail

convertCharset

public static String convertCharset(String input,
                                    String inputCharset,
                                    String outputCharset)
                             throws IOException

Converts the character encoding of the supplied input value.

Parameters:

input - input value to apply conversion

inputCharset - character set of the input value

outputCharset - desired character set of the output value

Returns:

the converted value

Throws:

IOException - problem converting character set

convertCharset

public static void convertCharset(InputStream input,
                                  String inputCharset,
                                  OutputStream output,
                                  String outputCharset)
                           throws IOException

Converts the character encoding of the supplied input.

Parameters:

input - input stream to apply conversion

inputCharset - character set of the input stream

output - where converted stream will be stored

outputCharset - desired character set of the output stream

Throws:

IOException - problem converting character set

detectCharset

public static String detectCharset(String input)
                            throws IOException

Detects the character encoding of a string.

Parameters:

input - the input to detect encoding on

Returns:

the character encoding official name or null if the input is null or blank

Throws:

IOException - if there is a problem find the character encoding

detectCharset

public static String detectCharset(String input,
                                   String declaredEncoding)

Detects the character encoding of a string. If the string has a declared character encoding, specifying it will influence the detection result.

Parameters:

input - the input to detect encoding on

declaredEncoding - declared input encoding, if known

Returns:

the character encoding official name or null if the input is null or blank

detectCharset

public static String detectCharset(InputStream input)
                            throws IOException

Detects the character encoding of an input stream. InputStream.markSupported() must return true otherwise no decoding will be attempted.

Parameters:

input - the input to detect encoding on

Returns:

the character encoding official name or null if input is null

Throws:

IOException - if there is a problem find the character encoding

detectCharset

public static String detectCharset(InputStream input,
                                   String declaredEncoding)
                            throws IOException

Detects the character encoding of an input stream. If the string has a declared character encoding, specifying it will influence the detection result. InputStream.markSupported() must return true otherwise no decoding will be attempted.

Parameters:

input - the input to detect encoding on

declaredEncoding - declared input encoding, if known

Returns:

the character encoding official name or null if input is null

Throws:

IOException - if there is a problem find the character encoding

detectsCharset

public static String detectsCharset(Doc doc)
                             throws IOException

Detects a document character encoding. It first checks if it is defined in the document DocInfo.getContentEncoding(). If not, it will attempt to detect it from the document input stream. This method will NOT set the detected encoding on the DocInfo. If unable to detect, UTF-8 is assumed.

Parameters:

doc - document to detect encoding on

Returns:

string representation of character encoding

Throws:

IOException - problem detecting charset

Since:

3.0.0

detectCharsetIfBlank

public static String detectCharsetIfBlank(String charset,
                                          Doc doc)
                                   throws IOException

Detects a document character encoding if the supplied charset is blank. When blank, it checks if it is defined in the document DocInfo.getContentEncoding(). If not, it will attempt to detect it from the document input stream. This method will NOT set the detected encoding on the DocInfo. If unable to detect, UTF-8 is assumed.

Parameters:

charset - character encoding to use if not blank

doc - document to detect encoding on

Returns:

supplied charset if not blank, or the detected charset

Throws:

IOException - problem detecting charset

Since:

3.0.0

detectCharsetIfBlank

public static String detectCharsetIfBlank(String charset,
                                          InputStream is)
                                   throws IOException

Detects a document character encoding if the supplied charset is blank. When blank, it will attempt to detect it from the input stream. If unable to detect, UTF-8 is assumed.

Parameters:

charset - character encoding to use if not blank

is - input stream

Returns:

supplied charset if not blank, or the detected charset

Throws:

IOException - problem detecting charset

Since:

3.0.0

firstNonBlankOrUTF8

public static String firstNonBlankOrUTF8(String... charsets)

Returns the first non-blank character encoding, or returns UTF-8 if they are all blank.

Parameters:

charsets - character encodings to test

Returns:

first non-blank, or UTF-8

Since:

3.0.0

firstNonBlankOrUTF8

public static String firstNonBlankOrUTF8(ParseState parseState,
                                         String... charsets)

Returns the first non-blank character encoding, or returns UTF-8 if they are all blank or in post-parse state. That is, UTF-8 is always returned if parsing has already occurred (since parsing converts content encoding to UTF-8).

Parameters:

parseState - document parsing state

charsets - character encodings to test

Returns:

first non-blank, or UTF-8

Since:

3.0.0