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-rw-r--r--server/src/org/jsoup/helper/StringUtil.java140
1 files changed, 140 insertions, 0 deletions
diff --git a/server/src/org/jsoup/helper/StringUtil.java b/server/src/org/jsoup/helper/StringUtil.java
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+++ b/server/src/org/jsoup/helper/StringUtil.java
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+package org.jsoup.helper;
+
+import java.util.Collection;
+import java.util.Iterator;
+
+/**
+ * A minimal String utility class. Designed for internal jsoup use only.
+ */
+public final class StringUtil {
+ // memoised padding up to 10
+ private static final String[] padding = {"", " ", " ", " ", " ", " ", " ", " ", " ", " ", " "};
+
+ /**
+ * Join a collection of strings by a seperator
+ * @param strings collection of string objects
+ * @param sep string to place between strings
+ * @return joined string
+ */
+ public static String join(Collection strings, String sep) {
+ return join(strings.iterator(), sep);
+ }
+
+ /**
+ * Join a collection of strings by a seperator
+ * @param strings iterator of string objects
+ * @param sep string to place between strings
+ * @return joined string
+ */
+ public static String join(Iterator strings, String sep) {
+ if (!strings.hasNext())
+ return "";
+
+ String start = strings.next().toString();
+ if (!strings.hasNext()) // only one, avoid builder
+ return start;
+
+ StringBuilder sb = new StringBuilder(64).append(start);
+ while (strings.hasNext()) {
+ sb.append(sep);
+ sb.append(strings.next());
+ }
+ return sb.toString();
+ }
+
+ /**
+ * Returns space padding
+ * @param width amount of padding desired
+ * @return string of spaces * width
+ */
+ public static String padding(int width) {
+ if (width < 0)
+ throw new IllegalArgumentException("width must be > 0");
+
+ if (width < padding.length)
+ return padding[width];
+
+ char[] out = new char[width];
+ for (int i = 0; i < width; i++)
+ out[i] = ' ';
+ return String.valueOf(out);
+ }
+
+ /**
+ * Tests if a string is blank: null, emtpy, or only whitespace (" ", \r\n, \t, etc)
+ * @param string string to test
+ * @return if string is blank
+ */
+ public static boolean isBlank(String string) {
+ if (string == null || string.length() == 0)
+ return true;
+
+ int l = string.length();
+ for (int i = 0; i < l; i++) {
+ if (!StringUtil.isWhitespace(string.codePointAt(i)))
+ return false;
+ }
+ return true;
+ }
+
+ /**
+ * Tests if a string is numeric, i.e. contains only digit characters
+ * @param string string to test
+ * @return true if only digit chars, false if empty or null or contains non-digit chrs
+ */
+ public static boolean isNumeric(String string) {
+ if (string == null || string.length() == 0)
+ return false;
+
+ int l = string.length();
+ for (int i = 0; i < l; i++) {
+ if (!Character.isDigit(string.codePointAt(i)))
+ return false;
+ }
+ return true;
+ }
+
+ /**
+ * Tests if a code point is "whitespace" as defined in the HTML spec.
+ * @param c code point to test
+ * @return true if code point is whitespace, false otherwise
+ */
+ public static boolean isWhitespace(int c){
+ return c == ' ' || c == '\t' || c == '\n' || c == '\f' || c == '\r';
+ }
+
+ public static String normaliseWhitespace(String string) {
+ StringBuilder sb = new StringBuilder(string.length());
+
+ boolean lastWasWhite = false;
+ boolean modified = false;
+
+ int l = string.length();
+ for (int i = 0; i < l; i++) {
+ int c = string.codePointAt(i);
+ if (isWhitespace(c)) {
+ if (lastWasWhite) {
+ modified = true;
+ continue;
+ }
+ if (c != ' ')
+ modified = true;
+ sb.append(' ');
+ lastWasWhite = true;
+ }
+ else {
+ sb.appendCodePoint(c);
+ lastWasWhite = false;
+ }
+ }
+ return modified ? sb.toString() : string;
+ }
+
+ public static boolean in(String needle, String... haystack) {
+ for (String hay : haystack) {
+ if (hay.equals(needle))
+ return true;
+ }
+ return false;
+ }
+}