nonapi.io.github.classgraph.fileslice.reader

Class ClassfileReader

java.lang.Object

nonapi.io.github.classgraph.fileslice.reader.ClassfileReader

All Implemented Interfaces:

java.io.Closeable, java.lang.AutoCloseable, RandomAccessReader, SequentialReader

public class ClassfileReader
extends java.lang.Object
implements RandomAccessReader, SequentialReader, java.io.Closeable

A Slice reader that works as either a RandomAccessReader or a SequentialReader. The file is buffered up to the point it has been read so far. Reads in big endian order, as required by the classfile format.

Constructor Summary

Constructors

Constructor and Description
ClassfileReader(java.io.InputStream inputStream, Resource resourceToClose) Constructor for reader of module InputStream (which is not deflated).
ClassfileReader(Slice slice, Resource resourceToClose) Constructor.

Method Summary

Modifier and Type	Method and Description
byte[]	buf() Buf.
void	bufferTo(int numBytes) Ensure that the given number of bytes have been read into the buffer from the beginning of the slice.
void	close()
int	currPos() Curr pos.
int	read(long srcOffset, byte[] dstArr, int dstArrStart, int numBytes) Read bytes into a byte array.
int	read(long srcOffset, java.nio.ByteBuffer dstBuf, int dstBufStart, int numBytes) Read bytes into a ByteBuffer.
byte	readByte() Read a byte at the current cursor position.
byte	readByte(long offset) Read a byte at a specific offset (without changing the current cursor offset).
int	readInt() Read a int at the current cursor position.
int	readInt(long offset) Read a int at a specific offset (without changing the current cursor offset).
long	readLong() Read a long at the current cursor position.
long	readLong(long offset) Read a long at a specific offset (without changing the current cursor offset).
short	readShort() Read a short at the current cursor position.
short	readShort(long offset) Read a short at a specific offset (without changing the current cursor offset).
java.lang.String	readString(int numBytes) Reads the "modified UTF8" format defined in the Java classfile spec.
java.lang.String	readString(int numBytes, boolean replaceSlashWithDot, boolean stripLSemicolon) Reads the "modified UTF8" format defined in the Java classfile spec, optionally replacing '/' with '
java.lang.String	readString(long offset, int numBytes) Reads the "modified UTF8" format defined in the Java classfile spec.
java.lang.String	readString(long offset, int numBytes, boolean replaceSlashWithDot, boolean stripLSemicolon) Reads the "modified UTF8" format defined in the Java classfile spec, optionally replacing '/' with '
int	readUnsignedByte() Read an unsigned byte at the current cursor position.
int	readUnsignedByte(long offset) Read an unsigned byte at a specific offset (without changing the current cursor offset).
long	readUnsignedInt() Read a unsigned int at the current cursor position.
long	readUnsignedInt(long offset) Read a unsigned int at a specific offset (without changing the current cursor offset).
int	readUnsignedShort() Read a unsigned short at the current cursor position.
int	readUnsignedShort(long offset) Read a unsigned short at a specific offset (without changing the current cursor offset).
void	skip(int bytesToSkip) Skip the given number of bytes.

Methods inherited from class java.lang.Object

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

Constructor Detail

ClassfileReader

public ClassfileReader(Slice slice,
                       Resource resourceToClose)
                throws java.io.IOException

Constructor.

Parameters:

slice - the Slice to read.

resourceToClose - the resource to close when close() is called, or null.

Throws:

java.io.IOException - If an inflater cannot be opened on the Slice.

ClassfileReader

public ClassfileReader(java.io.InputStream inputStream,
                       Resource resourceToClose)
                throws java.io.IOException

Constructor for reader of module InputStream (which is not deflated).

Parameters:

inputStream - the InputStream to read from.

resourceToClose - the underlying resource to close when close() is called, or null.

Throws:

java.io.IOException - If an inflater cannot be opened on the Slice.

Method Detail

currPos

public int currPos()

Curr pos.

Returns:

the current read position.

buf

public byte[] buf()

Buf.

Returns:

the buffer.

bufferTo

public void bufferTo(int numBytes)
              throws java.io.IOException

Ensure that the given number of bytes have been read into the buffer from the beginning of the slice.

Parameters:

numBytes - the number of bytes to ensure have been buffered

Throws:

java.io.IOException - on EOF or if the bytes could not be read.

read

public int read(long srcOffset,
                byte[] dstArr,
                int dstArrStart,
                int numBytes)
         throws java.io.IOException

Description copied from interface: RandomAccessReader

Read bytes into a byte array.

Specified by:

read in interface RandomAccessReader

Parameters:

srcOffset - The offset to start reading from.

dstArr - The byte array to write into.

dstArrStart - The offset within the destination array to start writing at.

numBytes - The number of bytes to read.

Returns:

The number of bytes actually read, or -1 if no more bytes could be read.

Throws:

java.io.IOException - If there was an exception while reading.

read

public int read(long srcOffset,
                java.nio.ByteBuffer dstBuf,
                int dstBufStart,
                int numBytes)
         throws java.io.IOException

Description copied from interface: RandomAccessReader

Read bytes into a ByteBuffer.

Specified by:

read in interface RandomAccessReader

Parameters:

srcOffset - The offset to start reading from.

dstBuf - The ByteBuffer to write into.

dstBufStart - The offset within the destination buffer to start writing at.

numBytes - The number of bytes to read.

Returns:

The number of bytes actually read, or -1 if no more bytes could be read.

Throws:

java.io.IOException - If there was an exception while reading.

readByte

public byte readByte(long offset)
              throws java.io.IOException

Description copied from interface: RandomAccessReader

Read a byte at a specific offset (without changing the current cursor offset).

Specified by:

readByte in interface RandomAccessReader

Parameters:

offset - The buffer offset to read from.

Returns:

The byte at the offset.

Throws:

java.io.IOException - If there was an exception while reading.

readUnsignedByte

public int readUnsignedByte(long offset)
                     throws java.io.IOException

Description copied from interface: RandomAccessReader

Read an unsigned byte at a specific offset (without changing the current cursor offset).

Specified by:

readUnsignedByte in interface RandomAccessReader

Parameters:

offset - The buffer offset to read from.

Returns:

The unsigned byte at the offset.

Throws:

java.io.IOException - If there was an exception while reading.

readShort

public short readShort(long offset)
                throws java.io.IOException

Description copied from interface: RandomAccessReader

Read a short at a specific offset (without changing the current cursor offset).

Specified by:

readShort in interface RandomAccessReader

Parameters:

offset - The buffer offset to read from.

Returns:

The short at the offset.

Throws:

java.io.IOException - If there was an exception while reading.

readUnsignedShort

public int readUnsignedShort(long offset)
                      throws java.io.IOException

Description copied from interface: RandomAccessReader

Read a unsigned short at a specific offset (without changing the current cursor offset).

Specified by:

readUnsignedShort in interface RandomAccessReader

Parameters:

offset - The buffer offset to read from.

Returns:

The unsigned short at the offset.

Throws:

java.io.IOException - If there was an exception while reading.

readInt

public int readInt(long offset)
            throws java.io.IOException

Description copied from interface: RandomAccessReader

Read a int at a specific offset (without changing the current cursor offset).

Specified by:

readInt in interface RandomAccessReader

Parameters:

offset - The buffer offset to read from.

Returns:

The int at the offset.

Throws:

java.io.IOException - If there was an exception while reading.

readUnsignedInt

public long readUnsignedInt(long offset)
                     throws java.io.IOException

Description copied from interface: RandomAccessReader

Read a unsigned int at a specific offset (without changing the current cursor offset).

Specified by:

readUnsignedInt in interface RandomAccessReader

Parameters:

offset - The buffer offset to read from.

Returns:

The int at the offset, as a long.

Throws:

java.io.IOException - If there was an exception while reading.

readLong

public long readLong(long offset)
              throws java.io.IOException

Description copied from interface: RandomAccessReader

Read a long at a specific offset (without changing the current cursor offset).

Specified by:

readLong in interface RandomAccessReader

Parameters:

offset - The buffer offset to read from.

Returns:

The long at the offset.

Throws:

java.io.IOException - If there was an exception while reading.

readByte

public byte readByte()
              throws java.io.IOException

Description copied from interface: SequentialReader

Read a byte at the current cursor position.

Specified by:

readByte in interface SequentialReader

Returns:

The byte at the current cursor position.

Throws:

java.io.IOException - If there was an exception while reading.

readUnsignedByte

public int readUnsignedByte()
                     throws java.io.IOException

Description copied from interface: SequentialReader

Read an unsigned byte at the current cursor position.

Specified by:

readUnsignedByte in interface SequentialReader

Returns:

The unsigned byte at the current cursor position.

Throws:

java.io.IOException - If there was an exception while reading.

readShort

public short readShort()
                throws java.io.IOException

Description copied from interface: SequentialReader

Read a short at the current cursor position.

Specified by:

readShort in interface SequentialReader

Returns:

The short at the current cursor position.

Throws:

java.io.IOException - If there was an exception while reading.

readUnsignedShort

public int readUnsignedShort()
                      throws java.io.IOException

Description copied from interface: SequentialReader

Read a unsigned short at the current cursor position.

Specified by:

readUnsignedShort in interface SequentialReader

Returns:

The unsigned shortat the current cursor position.

Throws:

java.io.IOException - If there was an exception while reading.

readInt

public int readInt()
            throws java.io.IOException

Description copied from interface: SequentialReader

Read a int at the current cursor position.

Specified by:

readInt in interface SequentialReader

Returns:

The int at the current cursor position.

Throws:

java.io.IOException - If there was an exception while reading.

readUnsignedInt

public long readUnsignedInt()
                     throws java.io.IOException

Description copied from interface: SequentialReader

Read a unsigned int at the current cursor position.

Specified by:

readUnsignedInt in interface SequentialReader

Returns:

The int at the current cursor position, as a long.

Throws:

java.io.IOException - If there was an exception while reading.

readLong

public long readLong()
              throws java.io.IOException

Description copied from interface: SequentialReader

Read a long at the current cursor position.

Specified by:

readLong in interface SequentialReader

Returns:

The long at the current cursor position.

Throws:

java.io.IOException - If there was an exception while reading.

skip

public void skip(int bytesToSkip)
          throws java.io.IOException

Description copied from interface: SequentialReader

Skip the given number of bytes.

Specified by:

skip in interface SequentialReader

Parameters:

bytesToSkip - The number of bytes to skip.

Throws:

java.io.IOException - If there was an exception while reading.

readString

public java.lang.String readString(long offset,
                                   int numBytes,
                                   boolean replaceSlashWithDot,
                                   boolean stripLSemicolon)
                            throws java.io.IOException

Description copied from interface: RandomAccessReader

Reads the "modified UTF8" format defined in the Java classfile spec, optionally replacing '/' with '.', and optionally removing the prefix "L" and the suffix ";".

Specified by:

readString in interface RandomAccessReader

Parameters:

offset - The start offset of the string.

numBytes - The number of bytes of the UTF8 encoding of the string.

replaceSlashWithDot - If true, replace '/' with '.'.

stripLSemicolon - If true, string final ';' character.

Returns:

The string.

Throws:

java.io.IOException - If an I/O exception occurs.

readString

public java.lang.String readString(int numBytes,
                                   boolean replaceSlashWithDot,
                                   boolean stripLSemicolon)
                            throws java.io.IOException

Description copied from interface: SequentialReader

Reads the "modified UTF8" format defined in the Java classfile spec, optionally replacing '/' with '.', and optionally removing the prefix "L" and the suffix ";".

Specified by:

readString in interface SequentialReader

Parameters:

numBytes - The number of bytes of the UTF8 encoding of the string.

replaceSlashWithDot - If true, replace '/' with '.'.

stripLSemicolon - If true, string final ';' character.

Returns:

The string.

Throws:

java.io.IOException - If an I/O exception occurs.

readString

public java.lang.String readString(long offset,
                                   int numBytes)
                            throws java.io.IOException

Description copied from interface: RandomAccessReader

Reads the "modified UTF8" format defined in the Java classfile spec.

Specified by:

readString in interface RandomAccessReader

Parameters:

offset - The start offset of the string.

numBytes - The number of bytes of the UTF8 encoding of the string.

Returns:

The string.

Throws:

java.io.IOException - If an I/O exception occurs.

readString

public java.lang.String readString(int numBytes)
                            throws java.io.IOException

Description copied from interface: SequentialReader

Reads the "modified UTF8" format defined in the Java classfile spec.

Specified by:

readString in interface SequentialReader

Parameters:

numBytes - The number of bytes of the UTF8 encoding of the string.

Returns:

The string.

Throws:

java.io.IOException - If an I/O exception occurs.

close

public void close()

Specified by:

close in interface java.io.Closeable

Specified by:

close in interface java.lang.AutoCloseable