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The Java™ Tutorials
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Numbers and Strings
Numbers
The Numbers Classes
Formatting Numeric Print Output
Beyond Basic Arithmetic
Summary of Numbers
Questions and Exercises
Characters
Strings
Converting Between Numbers and Strings
Manipulating Characters in a String
Comparing Strings and Portions of Strings
The StringBuilder Class
Summary of Characters and Strings
Autoboxing and Unboxing
Questions and Exercises
Trail: Learning the Java Language
Lesson: Numbers and Strings
Section: Strings
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# Comparing Strings and Portions of Strings

The `String` class has a number of methods for comparing strings and portions of strings. The following table lists these methods.

Methods for Comparing Strings
Method | Description
--- | ---
`boolean endsWith(String suffix) boolean startsWith(String prefix)` | Returns `true` if this string ends with or begins with the substring specified as an argument to the method.
`boolean startsWith(String prefix, int offset)` | Considers the string beginning at the index `offset`, and returns `true` if it begins with the substring specified as an argument.
`int compareTo(String anotherString)` | Compares two strings lexicographically. Returns an integer indicating whether this string is greater than (result is > 0), equal to (result is = 0), or less than (result is < 0) the argument.
`int compareToIgnoreCase(String str)` | Compares two strings lexicographically, ignoring differences in case. Returns an integer indicating whether this string is greater than (result is > 0), equal to (result is = 0), or less than (result is < 0) the argument.
`boolean equals(Object anObject)` | Returns `true` if and only if the argument is a `String` object that represents the same sequence of characters as this object.
`boolean equalsIgnoreCase(String anotherString)` | Returns `true` if and only if the argument is a `String` object that represents the same sequence of characters as this object, ignoring differences in case.
`boolean regionMatches(int toffset, String other, int ooffset, int len)` | Tests whether the specified region of this string matches the specified region of the String argument. Region is of length `len` and begins at the index `toffset` for this string and `ooffset` for the other string.
`boolean regionMatches(boolean ignoreCase, int toffset, String other, int ooffset, int len)` | Tests whether the specified region of this string matches the specified region of the String argument. Region is of length `len` and begins at the index `toffset` for this string and `ooffset` for the other string. The boolean argument indicates whether case should be ignored; if true, case is ignored when comparing characters.
`boolean matches(String regex)` | Tests whether this string matches the specified regular expression. Regular expressions are discussed in the lesson titled "Regular Expressions."

The following program, `RegionMatchesDemo`, uses the `regionMatches` method to search for a string within another string:

    public class RegionMatchesDemo {
        public static void main(String[] args) {
            String searchMe = "Green Eggs and Ham";
            String findMe = "Eggs";
            int searchMeLength = searchMe.length();
            int findMeLength = findMe.length();
            boolean foundIt = false;
            for (int i = 0;
                 i <= (searchMeLength - findMeLength);
                 i++) {
               if (searchMe.regionMatches(i, findMe, 0, findMeLength)) {
                  foundIt = true;
                  System.out.println(searchMe.substring(i, i + findMeLength));
                  break;
               }
            }
            if (!foundIt)
                System.out.println("No match found.");
        }
    }

The output from this program is `Eggs`.

The program steps through the string referred to by `searchMe` one character at a time. For each character, the program calls the regionMatches method to determine whether the substring beginning with the current character matches the string the program is looking for.

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