org.antlr.v4.runtime.misc.Utils Maven / Gradle / Ivy
/*
* Copyright (c) 2012-2017 The ANTLR Project. All rights reserved.
* Use of this file is governed by the BSD 3-clause license that
* can be found in the LICENSE.txt file in the project root.
*/
package org.antlr.v4.runtime.misc;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.util.Arrays;
import java.util.BitSet;
import java.util.Collection;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
public class Utils {
// Seriously: why isn't this built in to java? ugh!
public static String join(Iterator iter, String separator) {
StringBuilder buf = new StringBuilder();
while ( iter.hasNext() ) {
buf.append(iter.next());
if ( iter.hasNext() ) {
buf.append(separator);
}
}
return buf.toString();
}
public static String join(T[] array, String separator) {
StringBuilder builder = new StringBuilder();
for (int i = 0; i < array.length; i++) {
builder.append(array[i]);
if (i < array.length - 1) {
builder.append(separator);
}
}
return builder.toString();
}
public static int numNonnull(Object[] data) {
int n = 0;
if ( data == null ) return n;
for (Object o : data) {
if ( o!=null ) n++;
}
return n;
}
public static void removeAllElements(Collection data, T value) {
if ( data==null ) return;
while ( data.contains(value) ) data.remove(value);
}
public static String escapeWhitespace(String s, boolean escapeSpaces) {
StringBuilder buf = new StringBuilder();
for (char c : s.toCharArray()) {
if ( c==' ' && escapeSpaces ) buf.append('\u00B7');
else if ( c=='\t' ) buf.append("\\t");
else if ( c=='\n' ) buf.append("\\n");
else if ( c=='\r' ) buf.append("\\r");
else buf.append(c);
}
return buf.toString();
}
public static void writeFile(String fileName, String content) throws IOException {
writeFile(fileName, content, null);
}
public static void writeFile(String fileName, String content, String encoding) throws IOException {
File f = new File(fileName);
FileOutputStream fos = new FileOutputStream(f);
OutputStreamWriter osw;
if (encoding != null) {
osw = new OutputStreamWriter(fos, encoding);
}
else {
osw = new OutputStreamWriter(fos);
}
try {
osw.write(content);
}
finally {
osw.close();
}
}
public static char[] readFile(String fileName) throws IOException {
return readFile(fileName, null);
}
public static char[] readFile(String fileName, String encoding) throws IOException {
File f = new File(fileName);
int size = (int)f.length();
InputStreamReader isr;
FileInputStream fis = new FileInputStream(fileName);
if ( encoding!=null ) {
isr = new InputStreamReader(fis, encoding);
}
else {
isr = new InputStreamReader(fis);
}
char[] data = null;
try {
data = new char[size];
int n = isr.read(data);
if (n < data.length) {
data = Arrays.copyOf(data, n);
}
}
finally {
isr.close();
}
return data;
}
/** Convert array of strings to string→index map. Useful for
* converting rulenames to name→ruleindex map.
*/
public static Map toMap(String[] keys) {
Map m = new HashMap();
for (int i=0; i= 0 ) {
s.add(i);
i = bits.nextSetBit(i+1);
}
return s;
}
/** @since 4.6 */
public static String expandTabs(String s, int tabSize) {
if ( s==null ) return null;
StringBuilder buf = new StringBuilder();
int col = 0;
for (int i = 0; i