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/* ____ ____ ____ ____ ______ *\
** / __// __ \/ __// __ \/ ____/ SOcos COmpiles Scala **
** __\_ \/ /_/ / /__/ /_/ /\_ \ (c) 2002, LAMP/EPFL **
** /_____/\____/\___/\____/____/ **
\* */
// $Id$
package ch.epfl.lamp.util;
import java.io.File;
import java.io.InputStream;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.util.ArrayList;
/**
* This class represents a single source file.
*/
public class SourceFile {
//########################################################################
// Public Constants
/** Constants used for source parsing */
public static final byte LF = 0x0A;
public static final byte FF = 0x0C;
public static final byte CR = 0x0D;
public static final byte SU = 0x1A;
//########################################################################
// Private Fields
/** The name of this source file */
private final String name;
/** The content of source this file */
private final byte[] bytes;
/** The encoding of this source file or null if unspecified */
private String encoding;
/** The position of the last line returned by getLine */
private int lineNumber = 0;
private int lineStart = 0;
private int lineLength = 0;
private int nextIndex = 0;
//########################################################################
// Public Constructors
/** Initializes a new instance. */
public SourceFile(String name) throws IOException {
this(new File(name));
}
/** Initializes a new instance. */
public SourceFile(File name) throws IOException {
this(name.toString(), read(name));
}
/** Initializes a new instance. */
public SourceFile(String name, InputStream input) throws IOException {
this(name, read(name, input));
}
/** Initializes a new instance. */
public SourceFile(String name, byte[] bytes) {
this.name = name;
this.bytes = normalize(bytes);
}
//########################################################################
// Public Methods
/** Returns the name of this source file. */
public String name() {
return name;
}
/** Returns the content of this source file. */
public byte[] bytes() {
return bytes;
}
/** Sets the encoding of the file. */
public void setEncoding(String encoding) {
this.encoding = encoding;
}
/** Returns the short name (name without path) of this source file. */
public String getShortName() {
int start = name.lastIndexOf(File.separatorChar);
return start < 0 ? name : name.substring(start + 1);
}
/**
* Returns an instance of Position representing the given line and
* column of this source file.
*/
public Position getPosition(int line, int column) {
return new Position(this, line, column);
}
/** Returns the content of the given line. */
public String getLine(int line) {
int index = lineNumber <= line ? nextIndex : (lineNumber = 0);
for (; index < bytes.length && lineNumber < line; lineNumber++) {
lineStart = index;
for (; index < bytes.length; index++) {
if (bytes[index] == CR) break;
if (bytes[index] == LF) break;
if (bytes[index] == FF) break;
}
lineLength = index - lineStart;
if (index < bytes.length) index++;
if (index < bytes.length)
if (bytes[index - 1] == CR && bytes[index] == LF) index++;
}
nextIndex = index;
try {
return encoding != null ?
new String(bytes, lineStart, lineLength, encoding) :
new String(bytes, lineStart, lineLength);
} catch (UnsupportedEncodingException exception) {
throw new Error(exception); // !!! use ApplicationError
}
}
/** Returns the name of this source file. */
public String toString() {
return name;
}
//########################################################################
// Private Methods
/** Reads the file and returns its content as a byte array. */
private static byte[] read(File file) throws IOException {
InputStream input = new FileInputStream(file);
try {
return read(file.toString(), input);
} finally {
input.close();
}
}
/** Reads the InputStream and returns its content as a byte array. */
private static byte[] read(String name, InputStream input)
throws IOException
{
try {
byte[] bytes = new byte[input.available() + 1];
if (input.read(bytes) != bytes.length - 1) throw new IOException();
bytes[bytes.length - 1] = SU;
return bytes;
} catch (IOException exception) {
throw new IOException("cannot read '" + name + "'");
}
}
/** Ensures that the last byte of the array is SU. */
private static byte[] normalize(byte[] input) {
if (input.length > 0 && input[input.length - 1] == SU) return input;
byte[] bytes = new byte[input.length + 1];
System.arraycopy(input, 0, bytes, 0, input.length);
bytes[input.length] = SU;
return bytes;
}
//########################################################################
}
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