Java tutorial
package com.fasterxml.jackson.core.io; import java.util.Arrays; import com.fasterxml.jackson.core.SerializableString; /** * Abstract base class that defines interface for customizing character * escaping aspects for String values, for formats that use escaping. * For JSON this applies to both property names and String values. */ public abstract class CharacterEscapes implements java.io.Serializable // since 2.1 { private static final long serialVersionUID = 1L; /** * Value used for lookup tables to indicate that matching characters * do not need to be escaped. */ public final static int ESCAPE_NONE = 0; /** * Value used for lookup tables to indicate that matching characters * are to be escaped using standard escaping; for JSON this means * (for example) using "backslash - u" escape method. */ public final static int ESCAPE_STANDARD = -1; /** * Value used for lookup tables to indicate that matching characters * will need custom escapes; and that another call * to {@link #getEscapeSequence} is needed to figure out exact escape * sequence to output. */ public final static int ESCAPE_CUSTOM = -2; /** * Method generators can call to get lookup table for determining * escape handling for first 128 characters of Unicode (ASCII * characters. Caller is not to modify contents of this array, since * this is expected to be a shared copy. * * @return Array with size of at least 128, where first 128 entries * have either one of <code>ESCAPE_xxx</code> constants, or non-zero positive * integer (meaning of which is data format specific; for JSON it means * that combination of backslash and character with that value is to be used) * to indicate that specific escape sequence is to be used. */ public abstract int[] getEscapeCodesForAscii(); /** * Method generators can call to get lookup table for determining * exact escape sequence to use for given character. * It can be called for any character, but typically is called for * either for ASCII characters for which custom escape * sequence is needed; or for any non-ASCII character. */ public abstract SerializableString getEscapeSequence(int ch); /** * Helper method that can be used to get a copy of standard JSON * escape definitions; this is useful when just wanting to slightly * customize definitions. Caller can modify this array as it sees * fit and usually returns modified instance via {@link #getEscapeCodesForAscii} */ public static int[] standardAsciiEscapesForJSON() { int[] esc = CharTypes.get7BitOutputEscapes(); return Arrays.copyOf(esc, esc.length); } }