Example usage for java.lang CharSequence charAt

Introduction

In this page you can find the example usage for java.lang CharSequence charAt.

Prototype

char charAt(int index);

Source Link

Document

Returns the char value at the specified index.

Usage

From source file:ths.commons.util.StringUtils.java

/**
 * <p>Checks if a CharSequence is whitespace, empty ("") or null.</p>
 *
 * <pre>//w w  w . j a  v a 2  s  .  c o  m
 * StringUtils.isBlank(null)      = true
 * StringUtils.isBlank("")        = true
 * StringUtils.isBlank(" ")       = true
 * StringUtils.isBlank("bob")     = false
 * StringUtils.isBlank("  bob  ") = false
 * </pre>
 *
 * @param cs  the CharSequence to check, may be null
 * @return {@code true} if the CharSequence is null, empty or whitespace
 */
public static boolean isBlank(CharSequence cs) {
    int strLen;
    if (cs == null || (strLen = cs.length()) == 0) {
        return true;
    }
    for (int i = 0; i < strLen; i++) {
        if ((Character.isWhitespace(cs.charAt(i)) == false)) {
            return false;
        }
    }
    return true;
}

From source file:org.apache.commons.lang3.StringUtils.java

/**
 * <p>Checks if the CharSequence contains only Unicode digits or space
 * ({@code ' '})./* ww w.j a va  2s  . com*/
 * A decimal point is not a Unicode digit and returns false.</p>
 *
 * <p>{@code null} will return {@code false}.
 * An empty CharSequence (length()=0) will return {@code true}.</p>
 *
 * <pre>
 * StringUtils.isNumericSpace(null)   = false
 * StringUtils.isNumericSpace("")     = true
 * StringUtils.isNumericSpace("  ")   = true
 * StringUtils.isNumericSpace("123")  = true
 * StringUtils.isNumericSpace("12 3") = true
 * StringUtils.isNumericSpace("ab2c") = false
 * StringUtils.isNumericSpace("12-3") = false
 * StringUtils.isNumericSpace("12.3") = false
 * </pre>
 *
 * @param cs  the CharSequence to check, may be null
 * @return {@code true} if only contains digits or space,
 *  and is non-null
 * @since 3.0 Changed signature from isNumericSpace(String) to isNumericSpace(CharSequence)
 */
public static boolean isNumericSpace(CharSequence cs) {
    if (cs == null) {
        return false;
    }
    int sz = cs.length();
    for (int i = 0; i < sz; i++) {
        if (Character.isDigit(cs.charAt(i)) == false && cs.charAt(i) != ' ') {
            return false;
        }
    }
    return true;
}

From source file:org.apache.commons.lang3.StringUtils.java

/**
 * <p>Checks if the CharSequence contains only Unicode letters and
 * space (' ').</p>//from   w  w  w. j  a  va  2  s . c  o m
 *
 * <p>{@code null} will return {@code false}
 * An empty CharSequence (length()=0) will return {@code true}.</p>
 *
 * <pre>
 * StringUtils.isAlphaSpace(null)   = false
 * StringUtils.isAlphaSpace("")     = true
 * StringUtils.isAlphaSpace("  ")   = true
 * StringUtils.isAlphaSpace("abc")  = true
 * StringUtils.isAlphaSpace("ab c") = true
 * StringUtils.isAlphaSpace("ab2c") = false
 * StringUtils.isAlphaSpace("ab-c") = false
 * </pre>
 *
 * @param cs  the CharSequence to check, may be null
 * @return {@code true} if only contains letters and space,
 *  and is non-null
 * @since 3.0 Changed signature from isAlphaSpace(String) to isAlphaSpace(CharSequence)
 */
public static boolean isAlphaSpace(CharSequence cs) {
    if (cs == null) {
        return false;
    }
    int sz = cs.length();
    for (int i = 0; i < sz; i++) {
        if (Character.isLetter(cs.charAt(i)) == false && cs.charAt(i) != ' ') {
            return false;
        }
    }
    return true;
}

From source file:org.apache.commons.lang3.StringUtils.java

/**
 * <p>Checks if the CharSequence contains only whitespace.</p>
 *
 * <p>{@code null} will return {@code false}.
 * An empty CharSequence (length()=0) will return {@code true}.</p>
 *
 * <pre>/* w  w  w  .  ja va2s. c  om*/
 * StringUtils.isWhitespace(null)   = false
 * StringUtils.isWhitespace("")     = true
 * StringUtils.isWhitespace("  ")   = true
 * StringUtils.isWhitespace("abc")  = false
 * StringUtils.isWhitespace("ab2c") = false
 * StringUtils.isWhitespace("ab-c") = false
 * </pre>
 *
 * @param cs  the CharSequence to check, may be null
 * @return {@code true} if only contains whitespace, and is non-null
 * @since 2.0
 * @since 3.0 Changed signature from isWhitespace(String) to isWhitespace(CharSequence)
 */
public static boolean isWhitespace(CharSequence cs) {
    if (cs == null) {
        return false;
    }
    int sz = cs.length();
    for (int i = 0; i < sz; i++) {
        if (Character.isWhitespace(cs.charAt(i)) == false) {
            return false;
        }
    }
    return true;
}

From source file:org.apache.commons.lang3.StringUtils.java

/**
 * <p>Checks if the CharSequence contains only Unicode letters, digits
 * or space ({@code ' '}).</p>// ww w . j  ava 2  s  .c  o m
 *
 * <p>{@code null} will return {@code false}.
 * An empty CharSequence (length()=0) will return {@code true}.</p>
 *
 * <pre>
 * StringUtils.isAlphanumericSpace(null)   = false
 * StringUtils.isAlphanumericSpace("")     = true
 * StringUtils.isAlphanumericSpace("  ")   = true
 * StringUtils.isAlphanumericSpace("abc")  = true
 * StringUtils.isAlphanumericSpace("ab c") = true
 * StringUtils.isAlphanumericSpace("ab2c") = true
 * StringUtils.isAlphanumericSpace("ab-c") = false
 * </pre>
 *
 * @param cs  the CharSequence to check, may be null
 * @return {@code true} if only contains letters, digits or space,
 *  and is non-null
 * @since 3.0 Changed signature from isAlphanumericSpace(String) to isAlphanumericSpace(CharSequence)
 */
public static boolean isAlphanumericSpace(CharSequence cs) {
    if (cs == null) {
        return false;
    }
    int sz = cs.length();
    for (int i = 0; i < sz; i++) {
        if (Character.isLetterOrDigit(cs.charAt(i)) == false && cs.charAt(i) != ' ') {
            return false;
        }
    }
    return true;
}

From source file:org.apache.commons.lang3.StringUtils.java

/**
 * <p>Checks if the CharSequence contains only ASCII printable characters.</p>
 *
 * <p>{@code null} will return {@code false}.
 * An empty CharSequence (length()=0) will return {@code true}.</p>
 *
 * <pre>//from  w ww.  ja  va2  s.c  o m
 * StringUtils.isAsciiPrintable(null)     = false
 * StringUtils.isAsciiPrintable("")       = true
 * StringUtils.isAsciiPrintable(" ")      = true
 * StringUtils.isAsciiPrintable("Ceki")   = true
 * StringUtils.isAsciiPrintable("ab2c")   = true
 * StringUtils.isAsciiPrintable("!ab-c~") = true
 * StringUtils.isAsciiPrintable("\u0020") = true
 * StringUtils.isAsciiPrintable("\u0021") = true
 * StringUtils.isAsciiPrintable("\u007e") = true
 * StringUtils.isAsciiPrintable("\u007f") = false
 * StringUtils.isAsciiPrintable("Ceki G\u00fclc\u00fc") = false
 * </pre>
 *
 * @param cs the CharSequence to check, may be null
 * @return {@code true} if every character is in the range
 *  32 thru 126
 * @since 2.1
 * @since 3.0 Changed signature from isAsciiPrintable(String) to isAsciiPrintable(CharSequence)
 */
public static boolean isAsciiPrintable(CharSequence cs) {
    if (cs == null) {
        return false;
    }
    int sz = cs.length();
    for (int i = 0; i < sz; i++) {
        if (CharUtils.isAsciiPrintable(cs.charAt(i)) == false) {
            return false;
        }
    }
    return true;
}

From source file:org.apache.commons.lang3.StringUtils.java

/**
 * Check whether the given CharSequence contains any whitespace characters.
 * @param seq the CharSequence to check (may be {@code null})
 * @return {@code true} if the CharSequence is not empty and
 * contains at least 1 whitespace character
 * @see java.lang.Character#isWhitespace
 * @since 3.0/*  ww  w. java 2 s  . c o  m*/
 */
// From org.springframework.util.StringUtils, under Apache License 2.0
public static boolean containsWhitespace(CharSequence seq) {
    if (isEmpty(seq)) {
        return false;
    }
    int strLen = seq.length();
    for (int i = 0; i < strLen; i++) {
        if (Character.isWhitespace(seq.charAt(i))) {
            return true;
        }
    }
    return false;
}

From source file:org.apache.commons.lang3.StringUtils.java

/**
 * <p>Checks if the CharSequence contains only lowercase characters.</p>
 *
 * <p>{@code null} will return {@code false}.
 * An empty CharSequence (length()=0) will return {@code false}.</p>
 *
 * <pre>/*  ww  w  .j  a va2  s .  com*/
 * StringUtils.isAllLowerCase(null)   = false
 * StringUtils.isAllLowerCase("")     = false
 * StringUtils.isAllLowerCase("  ")   = false
 * StringUtils.isAllLowerCase("abc")  = true
 * StringUtils.isAllLowerCase("abC") = false
 * </pre>
 *
 * @param cs  the CharSequence to check, may be null
 * @return {@code true} if only contains lowercase characters, and is non-null
 * @since 2.5
 * @since 3.0 Changed signature from isAllLowerCase(String) to isAllLowerCase(CharSequence)
 */
public static boolean isAllLowerCase(CharSequence cs) {
    if (cs == null || isEmpty(cs)) {
        return false;
    }
    int sz = cs.length();
    for (int i = 0; i < sz; i++) {
        if (Character.isLowerCase(cs.charAt(i)) == false) {
            return false;
        }
    }
    return true;
}

From source file:org.apache.commons.lang3.StringUtils.java

/**
 * <p>Checks if the CharSequence contains only uppercase characters.</p>
 *
 * <p>{@code null} will return {@code false}.
 * An empty String (length()=0) will return {@code false}.</p>
 *
 * <pre>//from   www.j a va2s  .co m
 * StringUtils.isAllUpperCase(null)   = false
 * StringUtils.isAllUpperCase("")     = false
 * StringUtils.isAllUpperCase("  ")   = false
 * StringUtils.isAllUpperCase("ABC")  = true
 * StringUtils.isAllUpperCase("aBC") = false
 * </pre>
 *
 * @param cs the CharSequence to check, may be null
 * @return {@code true} if only contains uppercase characters, and is non-null
 * @since 2.5
 * @since 3.0 Changed signature from isAllUpperCase(String) to isAllUpperCase(CharSequence)
 */
public static boolean isAllUpperCase(CharSequence cs) {
    if (cs == null || isEmpty(cs)) {
        return false;
    }
    int sz = cs.length();
    for (int i = 0; i < sz; i++) {
        if (Character.isUpperCase(cs.charAt(i)) == false) {
            return false;
        }
    }
    return true;
}

From source file:org.apache.commons.lang3.StringUtils.java

/**
 * <p>Checks if the CharSequence contains only Unicode digits.
 * A decimal point is not a Unicode digit and returns false.</p>
 *
 * <p>{@code null} will return {@code false}.
 * An empty CharSequence (length()=0) will return {@code false}.</p>
 *
 * <pre>//  ww w. j  a  va 2s.  c  o  m
 * StringUtils.isNumeric(null)   = false
 * StringUtils.isNumeric("")     = false
 * StringUtils.isNumeric("  ")   = false
 * StringUtils.isNumeric("123")  = true
 * StringUtils.isNumeric("12 3") = false
 * StringUtils.isNumeric("ab2c") = false
 * StringUtils.isNumeric("12-3") = false
 * StringUtils.isNumeric("12.3") = false
 * </pre>
 *
 * @param cs  the CharSequence to check, may be null
 * @return {@code true} if only contains digits, and is non-null
 * @since 3.0 Changed signature from isNumeric(String) to isNumeric(CharSequence)
 * @since 3.0 Changed "" to return false and not true
 */
public static boolean isNumeric(CharSequence cs) {
    if (cs == null || cs.length() == 0) {
        return false;
    }
    int sz = cs.length();
    for (int i = 0; i < sz; i++) {
        if (Character.isDigit(cs.charAt(i)) == false) {
            return false;
        }
    }
    return true;
}