Automatic crossing of function names by eclipse in the standard StdIn class

I copied and pasted a StdIn Class in eclipse which was used to complete an assignment in Stacks but suprisingly the names of functions readDoubles, readStrings and readInts were crossed automatically single-line crossed by Eclipse (although in the code below they are not crossed but if one tries to copy the below code to eclipse the crossed function names again appear). Why does this happen?

The code of StdIn is given below::

package stackimplementation;

/*************************************************************************
 *  Compilation:  javac StdIn.java
 *  Execution:    java StdIn   (interactive test of basic functionality)
 *
 *  Reads in data of various types from standard input.
 *
 *************************************************************************/

import java.util.ArrayList;
import java.util.InputMismatchException;
import java.util.Locale;
import java.util.Scanner;
import java.util.regex.Pattern;

/**
 *  The <tt>StdIn</tt> class provides static methods for reading strings
 *  and numbers from standard input. See 
 *  <a href="http://introcs.cs.princeton.edu/15inout">Section 1.5</a> of
 *  <i>Introduction to Programming in Java: An Interdisciplinary Approach</i>
 *  by Robert Sedgewick and Kevin Wayne.
 *  <p>
 *  For uniformity across platforms, this class uses <tt>Locale.US</tt>
 *  for the locale and <tt>"UTF-8"</tt> for the character-set encoding.
 *  The English language locale is consistent with the formatting conventions
 *  for Java floating-point literals, command-line arguments
 *  (via {@link Double#parseDouble(String)}) and standard output.
 *  <p>
 *  Like {@link Scanner}, reading a <em>token</em> also consumes preceding Java
 *  whitespace; reading a line consumes the following end-of-line
 *  delimeter; reading a character consumes nothing extra. 
 *  <p>
 *  Whitespace is defined in {@link Character#isWhitespace(char)}. Newlines
 *  consist of \n, \r, \r\n, and Unicode hex code points 0x2028, 0x2029, 0x0085;
 *  see <tt><a href="http://www.docjar.com/html/api/java/util/Scanner.java.html">
 *  Scanner.java</a></tt> (NB: Java 6u23 and earlier uses only \r, \r, \r\n).
 *  <p>
 *  See {@link In} for a version that handles input from files, URLs,
 *  and sockets.
 *  <p>
 *  Note that Java's UTF-8 encoding does not recognize the optional byte-order
 *  mask. If the input begins with the optional byte-order mask, <tt>StdIn</tt>
 *  will have an extra character <tt>uFEFF</tt> at the beginning.
 *  For details, see http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4508058.
 *
 *  @author David Pritchard
 *  @author Robert Sedgewick
 *  @author Kevin Wayne
 */
public final class StdIn {

    // it doesn't make sense to instantiate this class
    private StdIn() { }

    private static Scanner scanner;

    /*** begin: section (1 of 2) of code duplicated from In to StdIn */

    // assume Unicode UTF-8 encoding
    private static final String CHARSET_NAME = "UTF-8";

    // assume language = English, country = US for consistency with System.out.
    private static final Locale LOCALE = Locale.US;

    // the default token separator; we maintain the invariant that this value
    // is held by the scanner's delimiter between calls
    private static final Pattern WHITESPACE_PATTERN = Pattern.compile("\\p{javaWhitespace}+");

    // makes whitespace characters significant
    private static final Pattern EMPTY_PATTERN = Pattern.compile("");

    // used to read the entire input
    private static final Pattern EVERYTHING_PATTERN = Pattern.compile("\\A");

    /*** end: section (1 of 2) of code duplicated from In to StdIn */

    /*** begin: section (2 of 2) of code duplicated from In to StdIn,
      *  with all methods changed from "public" to "public static" ***/

   /**
     * Is the input empty (except possibly for whitespace)? Use this
     * to know whether the next call to {@link #readString()}, 
     * {@link #readDouble()}, etc will succeed.
     * @return true if standard input is empty (except possibly
     *     for whitespae), and false otherwise
     */
    public static boolean isEmpty() {
        return !scanner.hasNext();
    }

   /**
     * Does the input have a next line? Use this to know whether the
     * next call to {@link #readLine()} will succeed. <p> Functionally
     * equivalent to {@link #hasNextChar()}.
     * @return true if standard input is empty, and false otherwise
     */
    public static boolean hasNextLine() {
        return scanner.hasNextLine();
    }

    /**
     * Is the input empty (including whitespace)? Use this to know 
     * whether the next call to {@link #readChar()} will succeed.
     * <p>Functionally equivalent to {@link #hasNextLine()}.
     * @return true if standard input is empty, and false otherwise
     */
    public static boolean hasNextChar() {
        scanner.useDelimiter(EMPTY_PATTERN);
        boolean result = scanner.hasNext();
        scanner.useDelimiter(WHITESPACE_PATTERN);
        return result;
    }


   /**
     * Reads and returns the next line, excluding the line separator if present.
     * @return the next line, excluding the line separator if present
     */
    public static String readLine() {
        String line;
        try                 { line = scanner.nextLine(); }
        catch (Exception e) { line = null;               }
        return line;
    }

    /**
     * Reads and returns the next character.
     * @return the next character
     */
    public static char readChar() {
        scanner.useDelimiter(EMPTY_PATTERN);
        String ch = scanner.next();
        assert (ch.length() == 1) : "Internal (Std)In.readChar() error!"
            + " Please contact the authors.";
        scanner.useDelimiter(WHITESPACE_PATTERN);
        return ch.charAt(0);
    }  


   /**
     * Reads and returns the remainder of the input, as a string.
     * @return the remainder of the input, as a string
     */
    public static String readAll() {
        if (!scanner.hasNextLine())
            return "";

        String result = scanner.useDelimiter(EVERYTHING_PATTERN).next();
        // not that important to reset delimeter, since now scanner is empty
        scanner.useDelimiter(WHITESPACE_PATTERN); // but let's do it anyway
        return result;
    }


   /**
     * Reads the next token  and returns the <tt>String</tt>.
     * @return the next <tt>String</tt>
     */
    public static String readString() {
        return scanner.next();
    }

   /**
     * Reads the next token from standard input, parses it as an integer, and returns the integer.
     * @return the next integer on standard input
     * @throws InputMismatchException if the next token cannot be parsed as an <tt>int</tt>
     */
    public static int readInt() {
        return scanner.nextInt();
    }

   /**
     * Reads the next token from standard input, parses it as a double, and returns the double.
     * @return the next double on standard input
     * @throws InputMismatchException if the next token cannot be parsed as a <tt>double</tt>
     */
    public static double readDouble() {
        return scanner.nextDouble();
    }

   /**
     * Reads the next token from standard input, parses it as a float, and returns the float.
     * @return the next float on standard input
     * @throws InputMismatchException if the next token cannot be parsed as a <tt>float</tt>
     */
    public static float readFloat() {
        return scanner.nextFloat();
    }

   /**
     * Reads the next token from standard input, parses it as a long integer, and returns the long integer.
     * @return the next long integer on standard input
     * @throws InputMismatchException if the next token cannot be parsed as a <tt>long</tt>
     */
    public static long readLong() {
        return scanner.nextLong();
    }

   /**
     * Reads the next token from standard input, parses it as a short integer, and returns the short integer.
     * @return the next short integer on standard input
     * @throws InputMismatchException if the next token cannot be parsed as a <tt>short</tt>
     */
    public static short readShort() {
        return scanner.nextShort();
    }

   /**
     * Reads the next token from standard input, parses it as a byte, and returns the byte.
     * @return the next byte on standard input
     * @throws InputMismatchException if the next token cannot be parsed as a <tt>byte</tt>
     */
    public static byte readByte() {
        return scanner.nextByte();
    }

    /**
     * Reads the next token from standard input, parses it as a boolean,
     * and returns the boolean.
     * @return the next boolean on standard input
     * @throws InputMismatchException if the next token cannot be parsed as a <tt>boolean</tt>:
     *    <tt>true</tt> or <tt>1</tt> for true, and <tt>false</tt> or <tt>0</tt> for false,
     *    ignoring case
     */
    public static boolean readBoolean() {
        String s = readString();
        if (s.equalsIgnoreCase("true"))  return true;
        if (s.equalsIgnoreCase("false")) return false;
        if (s.equals("1"))               return true;
        if (s.equals("0"))               return false;
        throw new InputMismatchException();
    }

    /**
     * Reads all remaining tokens from standard input and returns them as an array of strings.
     * @return all remaining tokens on standard input, as an array of strings
     */
    public static String[] readAllStrings() {
        // we could use readAll.trim().split(), but that's not consistent
        // because trim() uses characters 0x00..0x20 as whitespace
        String[] tokens = WHITESPACE_PATTERN.split(readAll());
        if (tokens.length == 0 || tokens[0].length() > 0)
            return tokens;

        // don't include first token if it is leading whitespace
        String[] decapitokens = new String[tokens.length-1];
        for (int i = 0; i < tokens.length - 1; i++)
            decapitokens[i] = tokens[i+1];
        return decapitokens;
    }

    /**
     * Reads all remaining lines from standard input and returns them as an array of strings.
     * @return all remaining lines on standard input, as an array of strings
     */
    public static String[] readAllLines() {
        ArrayList<String> lines = new ArrayList<String>();
        while (hasNextLine()) {
            lines.add(readLine());
        }
        return lines.toArray(new String[0]);
    }

    /**
     * Reads all remaining tokens from standard input, parses them as integers, and returns
     * them as an array of integers.
     * @return all remaining integers on standard input, as an array
     * @throws InputMismatchException if any token cannot be parsed as an <tt>int</tt>
     */
    public static int[] readAllInts() {
        String[] fields = readAllStrings();
        int[] vals = new int[fields.length];
        for (int i = 0; i < fields.length; i++)
            vals[i] = Integer.parseInt(fields[i]);
        return vals;
    }

    /**
     * Reads all remaining tokens from standard input, parses them as doubles, and returns
     * them as an array of doubles.
     * @return all remaining doubles on standard input, as an array
     * @throws InputMismatchException if any token cannot be parsed as a <tt>double</tt>
     */
    public static double[] readAllDoubles() {
        String[] fields = readAllStrings();
        double[] vals = new double[fields.length];
        for (int i = 0; i < fields.length; i++)
            vals[i] = Double.parseDouble(fields[i]);
        return vals;
    }

    /*** end: section (2 of 2) of code duplicated from In to StdIn */


    // do this once when StdIn is initialized
    static {
        resync();
    }

    /**
     * If StdIn changes, use this to reinitialize the scanner.
     */
    private static void resync() {
        setScanner(new Scanner(new java.io.BufferedInputStream(System.in), CHARSET_NAME));
    }

    private static void setScanner(Scanner scanner) {
        StdIn.scanner = scanner;
        StdIn.scanner.useLocale(LOCALE);
    }

   /**
     * Reads all remaining tokens, parses them as integers, and returns
     * them as an array of integers.
     * @return all remaining integers, as an array
     * @throws InputMismatchException if any token cannot be parsed as an <tt>int</tt>
     * @deprecated For more consistency, use {@link #readAllInts()}
     */
    public static int[] readInts() {
        return readAllInts();
    }

   /**
     * Reads all remaining tokens, parses them as doubles, and returns
     * them as an array of doubles.
     * @return all remaining doubles, as an array
     * @throws InputMismatchException if any token cannot be parsed as a <tt>double</tt>
     * @deprecated For more consistency, use {@link #readAllDoubles()}
     */
    public static double[] readDoubles() {
        return readAllDoubles();
    }

   /**
     * Reads all remaining tokens and returns them as an array of strings.
     * @return all remaining tokens, as an array of strings
     * @deprecated For more consistency, use {@link #readAllStrings()}
     */
    public static String[] readStrings() {
        return readAllStrings();
    }


    /**
     * Interactive test of basic functionality.
     */


}