org.sejda.sambox.input

Class ContentStreamParser

java.lang.Object

org.sejda.sambox.input.ContentStreamParser

All Implemented Interfaces:

Closeable, AutoCloseable

public class ContentStreamParser
extends Object

Component responsible for parsing a a content stream to extract operands and such.

Author:

Andrea Vacondio

Field Summary

Fields

Modifier and Type	Field and Description
static String	OBJ

Constructor Summary

Constructors

Constructor and Description
ContentStreamParser(PDContentStream stream)
ContentStreamParser(org.sejda.io.SeekableSource source)

Method Summary

Modifier and Type	Method and Description
void	close() Closes the SeekableSource this reader was created from.
boolean	isNextToken(String... values)
long	length()
Object	nextParsedToken()
long	position()
void	position(long offset) seeks to the given offset
int	readGenerationNumber() reads an integer and throws an IOException if the integer value has more than the maximum object revision (i.e.
String	readHexString() Reads a token conforming with PDF Hexadecimal Strings chap 7.3.4.3 PDF 32000-1:2008.
int	readInt()
String	readIntegerNumber() Reads a a token conforming with a PDF Integer object defined in Numeric Objects chap 7.3.3 PDF 32000-1:2008.
String	readLine() Reads bytes until the first end of line marker occurs.
String	readLiteralString() Reads a token conforming with PDF Literal Strings chap 7.3.4.2 PDF 32000-1:2008.
long	readLong()
String	readName() Reads a token conforming with PDF Name Objects chap 7.3.5 PDF 32000-1:2008.
String	readNumber() Reads a token conforming with PDF Numeric Objects chap 7.3.3 PDF 32000-1:2008.
long	readObjectNumber() Reads a long and throws an IOException if the long value is negative or has more than 10 digits (i.e.
String	readToken()
void	skipExpected(char ec) Skips one char and throws an exception if it is not the expected value.
void	skipExpected(String expected) Skips the expected given String
void	skipExpectedIndirectObjectDefinition(COSObjectKey expected) Skips an indirect object definition open tag (Ex.
void	skipIndirectObjectDefinition() Skips an indirect object definition open tag (Ex.
void	skipSpaces() Skips all spaces and comments that are present.
boolean	skipTokenIfValue(String... values) Skips the next token if it's value is one of the given ones
org.sejda.io.SeekableSource	source()
List<Object>	tokens()
void	unreadIfValid(int c) Unreads the given character if it's not -1
void	unreadSpaces() Unreads white spaces
void	unreadUntilSpaces() Unreads characters until it finds a white space

Methods inherited from class java.lang.Object

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

Field Detail

OBJ

public static final String OBJ

See Also:

Constant Field Values

Constructor Detail

ContentStreamParser

public ContentStreamParser(PDContentStream stream)
                    throws IOException

Throws:

IOException

ContentStreamParser

public ContentStreamParser(org.sejda.io.SeekableSource source)

Method Detail

tokens

public List<Object> tokens()
                    throws IOException

Returns:

a list of tokens retrieved parsing the source this parser was created from.

Throws:

IOException

nextParsedToken

public Object nextParsedToken()
                       throws IOException

Returns:

the next token parsed from the content stream

Throws:

IOException

close

public void close()
           throws IOException

Closes the SeekableSource this reader was created from.

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

Throws:

IOException

source

public org.sejda.io.SeekableSource source()

Returns:

the source for this reader

position

public long position()
              throws IOException

Returns:

the current position

Throws:

IOException

See Also:

SeekableSource#position()}

position

public void position(long offset)
              throws IOException

seeks to the given offset

Parameters:

offset - the new offset

Throws:

IOException

See Also:

SeekableSource#position(long)}

length

public long length()

Returns:

the source length

See Also:

SeekableSource#size()}

skipExpected

public final void skipExpected(String expected)
                        throws IOException

Skips the expected given String

Parameters:

expectedString - the String value that is expected.

Throws:

IOException - if the String char is not the expected value or if an I/O error occurs.

skipExpected

public void skipExpected(char ec)
                  throws IOException

Skips one char and throws an exception if it is not the expected value.

Parameters:

ec - the char value that is expected.

Throws:

IOException - if the read char is not the expected value or if an I/O error occurs.

skipTokenIfValue

public boolean skipTokenIfValue(String... values)
                         throws IOException

Skips the next token if it's value is one of the given ones

Parameters:

values - the values to skip

Returns:

true if the token is found and skipped, false otherwise.

Throws:

IOException - if there is an error reading from the stream

skipIndirectObjectDefinition

public void skipIndirectObjectDefinition()
                                  throws IOException

Skips an indirect object definition open tag (Ex. "12 0 obj") as defined in the chap 7.3.10 PDF 32000-1:2008.

Throws:

IOException - if we are reading a not valid indirect object definition open tag

skipExpectedIndirectObjectDefinition

public void skipExpectedIndirectObjectDefinition(COSObjectKey expected)
                                          throws IOException

Skips an indirect object definition open tag (Ex. "12 0 obj") as defined in the chap 7.3.10 PDF 32000-1:2008.

Parameters:

expected - object we are expecting to find

Throws:

IOException - if we are reading a not valid indirect object definition open tag or the object number or generation number don't match the expected object

readToken

public String readToken()
                 throws IOException

Returns:

The next token that was read from the stream.

Throws:

IOException - If there is an error reading from the stream.

See Also:

CharUtils.isEndOfName(int)

unreadSpaces

public void unreadSpaces()
                  throws IOException

Unreads white spaces

Throws:

IOException

unreadUntilSpaces

public void unreadUntilSpaces()
                       throws IOException

Unreads characters until it finds a white space

Throws:

IOException

isNextToken

public boolean isNextToken(String... values)
                    throws IOException

Parameters:

valid - values for the next token.

Returns:

true if the next token is one of the given values. false otherwise.

Throws:

IOException - if there is an error reading from the stream

readLine

public String readLine()
                throws IOException

Reads bytes until the first end of line marker occurs. NOTE: The EOL marker may consists of 1 (CR or LF) or 2 (CR and CL) bytes which is an important detail if one wants to unread the line.

Returns:

The characters between the current position and the end of the line.

Throws:

IOException - If there is an error reading from the stream.

readObjectNumber

public long readObjectNumber()
                      throws IOException

Reads a long and throws an IOException if the long value is negative or has more than 10 digits (i.e. : bigger than OBJECT_NUMBER_THRESHOLD)

Returns:

the object number being read.

Throws:

IOException - if an I/O error occurs

readGenerationNumber

public int readGenerationNumber()
                         throws IOException

reads an integer and throws an IOException if the integer value has more than the maximum object revision (i.e. : bigger than GENERATION_NUMBER_THRESHOLD)

Returns:

the generation number being read.

Throws:

IOException - if an I/O error occurs

readName

public String readName()
                throws IOException

Reads a token conforming with PDF Name Objects chap 7.3.5 PDF 32000-1:2008.

Returns:

the generation number being read.

Throws:

IOException - if an I/O error occurs

readInt

public int readInt()
            throws IOException

Returns:

The integer that was read from the stream.

Throws:

IOException - If there is an error reading from the stream.

readLong

public long readLong()
              throws IOException

Returns:

The long that was read from the stream.

Throws:

IOException - If there is an error reading from the stream.

readIntegerNumber

public final String readIntegerNumber()
                               throws IOException

Reads a a token conforming with a PDF Integer object defined in Numeric Objects chap 7.3.3 PDF 32000-1:2008.

Returns:

the token to parse as Integer or Long.

Throws:

IOException - If there is an error reading from the stream.

readNumber

public final String readNumber()
                        throws IOException

Reads a token conforming with PDF Numeric Objects chap 7.3.3 PDF 32000-1:2008.

Returns:

the token to parse as integer or real number.

Throws:

IOException - If there is an error reading from the stream.

readHexString

public final String readHexString()
                           throws IOException

Reads a token conforming with PDF Hexadecimal Strings chap 7.3.4.3 PDF 32000-1:2008. Any non hexadecimal char found while parsing the token is replace with the default '0' hex char.

Returns:

the token to parse as an hexadecimal string

Throws:

IOException - If there is an error reading from the stream.

readLiteralString

public String readLiteralString()
                         throws IOException

Reads a token conforming with PDF Literal Strings chap 7.3.4.2 PDF 32000-1:2008.

Returns:

the token to parse as a literal string

Throws:

IOException - If there is an error during parsing.

skipSpaces

public void skipSpaces()
                throws IOException

Skips all spaces and comments that are present.

Throws:

IOException - If there is an error reading from the stream.

unreadIfValid

public void unreadIfValid(int c)
                   throws IOException

Unreads the given character if it's not -1

Parameters:

c -

Throws:

IOException