/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
* JFlex 1.8.2 *
* Copyright (C) 1998-2018 Gerwin Klein <lsf@jflex.de> *
* All rights reserved. *
* *
* License: BSD *
* *
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
package jflex.skeleton;
import static java.nio.charset.StandardCharsets.UTF_8;
import static jflex.logging.Out.NL;
import java.io.BufferedReader;
import java.io.File;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.URL;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.util.ArrayList;
import java.util.List;
import jflex.exceptions.GeneratorException;
import jflex.l10n.ErrorMessages;
import jflex.logging.Out;
This class stores the skeleton of generated scanners.
The skeleton consists of several parts that can be emitted to a file. Usually there is a
portion of generated code (produced in class Emitter) between every two parts of skeleton code.
There is a static part (the skeleton code) and state based iterator part to this class. The iterator part is used to emit consecutive skeleton sections to some PrintWriter.
Author: Gerwin Klein See Also: Version: JFlex 1.8.2
/**
* This class stores the skeleton of generated scanners.
*
* <p>The skeleton consists of several parts that can be emitted to a file. Usually there is a
* portion of generated code (produced in class Emitter) between every two parts of skeleton code.
*
* <p>There is a static part (the skeleton code) and state based iterator part to this class. The
* iterator part is used to emit consecutive skeleton sections to some {@code PrintWriter}.
*
* @see jflex.generator.Emitter
* @author Gerwin Klein
* @version JFlex 1.8.2
*/
public class Skeleton {
location of default skeleton /** location of default skeleton */
private static final String DEFAULT_LOC = "jflex/skeleton.default";
expected number of sections in the skeleton file /** expected number of sections in the skeleton file */
private static final int size = 21;
The skeleton /** The skeleton */
public static String[] line;
static {
readDefault();
}
// the state based, iterator part of Skeleton:
The current part of the skeleton (an index of nextStop[]) /** The current part of the skeleton (an index of nextStop[]) */
private int pos;
The writer to write the skeleton-parts to /** The writer to write the skeleton-parts to */
private final PrintWriter out;
Creates a new skeleton (iterator) instance.
Params: - out – the writer to write the skeleton-parts to
/**
* Creates a new skeleton (iterator) instance.
*
* @param out the writer to write the skeleton-parts to
*/
public Skeleton(PrintWriter out) {
this.out = out;
}
Emits the next part of the skeleton /** Emits the next part of the skeleton */
public void emitNext() {
out.print(line[pos++]);
}
Make the skeleton private.
Replaces all occurrences of " public " in the skeleton with " private ".
/**
* Make the skeleton private.
*
* <p>Replaces all occurrences of " public " in the skeleton with " private ".
*/
public static void makePrivate() {
for (int i = 0; i < line.length; i++) {
line[i] = replace(" public ", " private ", line[i]);
}
}
Reads an external skeleton file for later use with this class.
Params: - skeletonFile – the file to read (must be != null and readable)
/**
* Reads an external skeleton file for later use with this class.
*
* @param skeletonFile the file to read (must be != null and readable)
*/
public static void readSkelFile(File skeletonFile) {
if (skeletonFile == null) throw new IllegalArgumentException("Skeleton file must not be null");
if (!skeletonFile.isFile() || !skeletonFile.canRead()) {
Out.error(ErrorMessages.CANNOT_READ_SKEL, skeletonFile.toString());
throw new GeneratorException();
}
Out.println(ErrorMessages.READING_SKEL, skeletonFile.toString());
try (BufferedReader reader =
Files.newBufferedReader(Paths.get(skeletonFile.toString()), UTF_8)) {
readSkel(reader);
} catch (IOException e) {
Out.error(ErrorMessages.SKEL_IO_ERROR);
throw new GeneratorException(e);
}
}
Reads an external skeleton file from a BufferedReader.
Params: - reader – the reader to read from (must be != null)
Throws: - IOException – if an IO error occurs
- GeneratorException – if the number of skeleton sections does not match
/**
* Reads an external skeleton file from a BufferedReader.
*
* @param reader the reader to read from (must be != null)
* @throws java.io.IOException if an IO error occurs
* @throws GeneratorException if the number of skeleton sections does not match
*/
public static void readSkel(BufferedReader reader) throws IOException {
List<String> lines = new ArrayList<>();
StringBuilder section = new StringBuilder();
String ln;
while ((ln = reader.readLine()) != null) {
if (ln.startsWith("---")) { // $NON-NLS-1$
lines.add(section.toString());
section.setLength(0);
} else {
section.append(ln);
section.append(NL);
}
}
if (section.length() > 0) lines.add(section.toString());
if (lines.size() != size) {
Out.error(ErrorMessages.WRONG_SKELETON);
throw new GeneratorException();
}
line = new String[size];
for (int i = 0; i < size; i++) line[i] = lines.get(i);
}
Replaces a with b in c.
Params: - a – the String to be replaced
- b – the replacement
- c – the String in which to replace a by b
Returns: a String object with a replaced by b in c
/**
* Replaces a with b in c.
*
* @param a the String to be replaced
* @param b the replacement
* @param c the String in which to replace a by b
* @return a String object with a replaced by b in c
*/
public static String replace(String a, String b, String c) {
StringBuilder result = new StringBuilder(c.length());
int i = 0;
int j = c.indexOf(a);
while (j >= i) {
result.append(c.substring(i, j));
result.append(b);
i = j + a.length();
j = c.indexOf(a, i);
}
result.append(c.substring(i, c.length()));
return result.toString();
}
(Re)load the default skeleton. Looks in the current system class path. /** (Re)load the default skeleton. Looks in the current system class path. */
public static void readDefault() {
ClassLoader l = Skeleton.class.getClassLoader();
URL url;
/* Try to load from same class loader as this class.
* Should work, but does not on OS/2 JDK 1.1.8 (see bug 1065521).
* Use system class loader in this case.
*/
if (l != null) {
url = l.getResource(DEFAULT_LOC);
} else {
url = ClassLoader.getSystemResource(DEFAULT_LOC);
}
if (url == null) {
Out.error(ErrorMessages.SKEL_IO_ERROR_DEFAULT);
throw new GeneratorException();
}
try (BufferedReader reader =
new BufferedReader(new InputStreamReader(url.openStream(), UTF_8))) {
readSkel(reader);
} catch (IOException e) {
Out.error(ErrorMessages.SKEL_IO_ERROR_DEFAULT);
throw new GeneratorException(e);
}
}
}