--- /dev/null
+//
+// Getdown - application installer, patcher and launcher
+// Copyright (C) 2004-2018 Getdown authors
+// https://github.com/threerings/getdown/blob/master/LICENSE
+
+package com.threerings.getdown.util;
+
+import java.util.StringTokenizer;
+
+public class StringUtil {
+
+ /**
+ * @return true if the specified string could be a valid URL (contains no illegal characters)
+ */
+ public static boolean couldBeValidUrl (String url)
+ {
+ return url.matches("[A-Za-z0-9\\-\\._~:/\\?#\\[\\]@!$&'\\(\\)\\*\\+,;=%]+");
+ }
+
+ /**
+ * @return true if the string is null or consists only of whitespace, false otherwise.
+ */
+ public static boolean isBlank (String value)
+ {
+ for (int ii = 0, ll = (value == null) ? 0 : value.length(); ii < ll; ii++) {
+ if (!Character.isWhitespace(value.charAt(ii))) {
+ return false;
+ }
+ }
+ return true;
+ }
+
+ /**
+ * Parses an array of integers from it's string representation. The array should be represented
+ * as a bare list of numbers separated by commas, for example:
+ *
+ * <pre>25, 17, 21, 99</pre>
+ *
+ * Any inability to parse the int array will result in the function returning null.
+ */
+ public static int[] parseIntArray (String source)
+ {
+ StringTokenizer tok = new StringTokenizer(source, ",");
+ int[] vals = new int[tok.countTokens()];
+ for (int i = 0; tok.hasMoreTokens(); i++) {
+ try {
+ // trim the whitespace from the token
+ vals[i] = Integer.parseInt(tok.nextToken().trim());
+ } catch (NumberFormatException nfe) {
+ return null;
+ }
+ }
+ return vals;
+ }
+
+ /**
+ * Parses an array of strings from a single string. The array should be represented as a bare
+ * list of strings separated by commas, for example:
+ *
+ * <pre>mary, had, a, little, lamb, and, an, escaped, comma,,</pre>
+ *
+ * If a comma is desired in one of the strings, it should be escaped by putting two commas in a
+ * row. Any inability to parse the string array will result in the function returning null.
+ */
+ public static String[] parseStringArray (String source)
+ {
+ return parseStringArray(source, false);
+ }
+
+ /**
+ * Like {@link #parseStringArray(String)} but can be instructed to invoke {@link String#intern}
+ * on the strings being parsed into the array.
+ */
+ public static String[] parseStringArray (String source, boolean intern)
+ {
+ int tcount = 0, tpos = -1, tstart = 0;
+
+ // empty strings result in zero length arrays
+ if (source.length() == 0) {
+ return new String[0];
+ }
+
+ // sort out escaped commas
+ source = source.replace(",,", "%COMMA%");
+
+ // count up the number of tokens
+ while ((tpos = source.indexOf(",", tpos+1)) != -1) {
+ tcount++;
+ }
+
+ String[] tokens = new String[tcount+1];
+ tpos = -1; tcount = 0;
+
+ // do the split
+ while ((tpos = source.indexOf(",", tpos+1)) != -1) {
+ tokens[tcount] = source.substring(tstart, tpos);
+ tokens[tcount] = tokens[tcount].trim().replace("%COMMA%", ",");
+ if (intern) {
+ tokens[tcount] = tokens[tcount].intern();
+ }
+ tstart = tpos+1;
+ tcount++;
+ }
+
+ // grab the last token
+ tokens[tcount] = source.substring(tstart);
+ tokens[tcount] = tokens[tcount].trim().replace("%COMMA%", ",");
+
+ return tokens;
+ }
+
+ /**
+ * @return the supplied string if it is non-null, "" if it is null.
+ */
+ public static String deNull (String value)
+ {
+ return (value == null) ? "" : value;
+ }
+
+ /**
+ * Generates a string from the supplied bytes that is the HEX encoded representation of those
+ * bytes. Returns the empty string for a <code>null</code> or empty byte array.
+ *
+ * @param bytes the bytes for which we want a string representation.
+ * @param count the number of bytes to stop at (which will be coerced into being {@code <=} the
+ * length of the array).
+ */
+ public static String hexlate (byte[] bytes, int count)
+ {
+ if (bytes == null) {
+ return "";
+ }
+
+ count = Math.min(count, bytes.length);
+ char[] chars = new char[count*2];
+
+ for (int i = 0; i < count; i++) {
+ int val = bytes[i];
+ if (val < 0) {
+ val += 256;
+ }
+ chars[2*i] = XLATE.charAt(val/16);
+ chars[2*i+1] = XLATE.charAt(val%16);
+ }
+
+ return new String(chars);
+ }
+
+ /**
+ * Generates a string from the supplied bytes that is the HEX encoded representation of those
+ * bytes.
+ */
+ public static String hexlate (byte[] bytes)
+ {
+ return (bytes == null) ? "" : hexlate(bytes, bytes.length);
+ }
+
+ /**
+ * Joins an array of strings (or objects which will be converted to strings) into a single
+ * string separated by commas.
+ */
+ public static String join (Object[] values)
+ {
+ return join(values, false);
+ }
+
+ /**
+ * Joins an array of strings into a single string, separated by commas, and optionally escaping
+ * commas that occur in the individual string values such that a subsequent call to {@link
+ * #parseStringArray} would recreate the string array properly. Any elements in the values
+ * array that are null will be treated as an empty string.
+ */
+ public static String join (Object[] values, boolean escape)
+ {
+ return join(values, ", ", escape);
+ }
+
+ /**
+ * Joins the supplied array of strings into a single string separated by the supplied
+ * separator.
+ */
+ public static String join (Object[] values, String separator)
+ {
+ return join(values, separator, false);
+ }
+
+ /**
+ * Helper function for the various <code>join</code> methods.
+ */
+ protected static String join (Object[] values, String separator, boolean escape)
+ {
+ StringBuilder buf = new StringBuilder();
+ int vlength = values.length;
+ for (int i = 0; i < vlength; i++) {
+ if (i > 0) {
+ buf.append(separator);
+ }
+ String value = (values[i] == null) ? "" : values[i].toString();
+ buf.append((escape) ? value.replace(",", ",,") : value);
+ }
+ return buf.toString();
+ }
+
+ /** Used by {@link #hexlate} and {@link #unhexlate}. */
+ protected static final String XLATE = "0123456789abcdef";
+}
git://source.jalview.org / jalview.git / blobdiff