javax.naming.ldap: public class: Rdn

javax.naming.ldap
public class: Rdn [javadoc | source]

java.lang.Object
   javax.naming.ldap.Rdn

All Implemented Interfaces:
Comparable, java$io$Serializable

This class represents a relative distinguished name, or RDN, which is a component of a distinguished name as specified by RFC 2253. An example of an RDN is "OU=Sales+CN=J.Smith". In this example, the RDN consist of multiple attribute type/value pairs. The RDN is parsed as described in the class description for LdapName .

The Rdn class represents an RDN as attribute type/value mappings, which can be viewed using Attributes . In addition, it contains convenience methods that allow easy retrieval of type and value when the Rdn consist of a single type/value pair, which is how it appears in a typical usage. It also contains helper methods that allow escaping of the unformatted attribute value and unescaping of the value formatted according to the escaping syntax defined in RFC2253. For methods that take or return attribute value as an Object, the value is either a String (in unescaped form) or a byte array.

Rdn will properly parse all valid RDNs, but does not attempt to detect all possible violations when parsing invalid RDNs. It is "generous" in accepting invalid RDNs. The "validity" of a name is determined ultimately when it is supplied to an LDAP server, which may accept or reject the name based on factors such as its schema information and interoperability considerations.

The following code example shows how to construct an Rdn using the constructor that takes type and value as arguments:

     Rdn rdn = new Rdn("cn", "Juicy, Fruit");
     System.out.println(rdn.toString());

The last line will print cn=Juicy\, Fruit. The unescapeValue() method can be used to unescape the escaped comma resulting in the original value "Juicy, Fruit". The escapeValue() method adds the escape back preceding the comma.

This class can be instantiated by a string representation of the RDN defined in RFC 2253 as shown in the following code example:

     Rdn rdn = new Rdn("cn=Juicy\\, Fruit");
     System.out.println(rdn.toString());

The last line will print cn=Juicy\, Fruit.

Concurrent multithreaded read-only access of an instance of Rdn need not be synchronized.

Unless otherwise noted, the behavior of passing a null argument to a constructor or method in this class will cause NullPointerException to be thrown.

since: 1.5 -

Constructor:

Constructor:
Rdn() { entries = new ArrayList(DEFAULT_SIZE); }
public Rdn(Attributes attrSet) throws InvalidNameException { if (attrSet.size() == 0) { throw new InvalidNameException("Attributes cannot be empty"); } entries = new ArrayList(attrSet.size()); NamingEnumeration attrs = attrSet.getAll(); try { for (int nEntries = 0; attrs.hasMore(); nEntries++) { RdnEntry entry = new RdnEntry(); Attribute attr = (Attribute) attrs.next(); entry.type = attr.getID(); entry.value = attr.get(); entries.add(nEntries, entry); } } catch (NamingException e) { InvalidNameException e2 = new InvalidNameException( e.getMessage()); e2.initCause(e); throw e2; } sort(); // arrange entries for comparison } Constructs an Rdn from the given attribute set. See Attributes . The string attribute values are not interpretted as RFC 2253 formatted RDN strings. That is, the values are used literally (not parsed) and assumed to be unescaped. Parameters: `attrSet` - The non-null and non-empty attributes containing type/value mappings. Throws: `InvalidNameException` - If contents of `attrSet` cannot be used to construct a valid RDN.
public Rdn(String rdnString) throws InvalidNameException { entries = new ArrayList(DEFAULT_SIZE); (new Rfc2253Parser(rdnString)).parseRdn(this); } Constructs an Rdn from the given string. This constructor takes a string formatted according to the rules defined in RFC 2253 and described in the class description for javax.naming.ldap.LdapName . Parameters: `rdnString` - The non-null and non-empty RFC2253 formatted string. Throws: `InvalidNameException` - If a syntax error occurs during parsing of the rdnString.
public Rdn(Rdn rdn) { entries = new ArrayList(rdn.entries.size()); entries.addAll(rdn.entries); } Constructs an Rdn from the given `rdn`. The contents of the `rdn` are simply copied into the newly created Rdn. Parameters: `rdn` - The non-null Rdn to be copied.
public Rdn(String type, Object value) throws InvalidNameException { if (value == null) { throw new NullPointerException("Cannot set value to null"); } if (type.equals("") \|\| isEmptyValue(value)) { throw new InvalidNameException( "type or value cannot be empty, type:" + type + " value:" + value); } entries = new ArrayList(DEFAULT_SIZE); put(type, value); } Constructs an Rdn from the given attribute type and value. The string attribute values are not interpretted as RFC 2253 formatted RDN strings. That is, the values are used literally (not parsed) and assumed to be unescaped. Parameters: `type` - The non-null and non-empty string attribute type. `value` - The non-null and non-empty attribute value. Throws: `InvalidNameException` - If type/value cannot be used to construct a valid RDN. Also see: toString()

 Rdn() {
        entries = new ArrayList(DEFAULT_SIZE);
}

 public Rdn(Attributes attrSet) throws InvalidNameException {
        if (attrSet.size() == 0) {
            throw new InvalidNameException("Attributes cannot be empty");
        }
        entries = new ArrayList(attrSet.size());
        NamingEnumeration attrs = attrSet.getAll();
        try {
            for (int nEntries = 0; attrs.hasMore(); nEntries++) {
                RdnEntry entry = new RdnEntry();
                Attribute attr = (Attribute) attrs.next();
                entry.type = attr.getID();
                entry.value = attr.get();
                entries.add(nEntries, entry);
            }
        } catch (NamingException e) {
            InvalidNameException e2 = new InvalidNameException(
                                        e.getMessage());
            e2.initCause(e);
            throw e2;
        }
        sort(); // arrange entries for comparison
}

Attributes

The string attribute values are not interpretted as RFC 2253 formatted RDN strings. That is, the values are used literally (not parsed) and assumed to be unescaped.

Parameters:

attrSet - The non-null and non-empty attributes containing type/value mappings.

Throws:

InvalidNameException - If contents of attrSet cannot be used to construct a valid RDN.

 public Rdn(String rdnString) throws InvalidNameException {
        entries = new ArrayList(DEFAULT_SIZE);
        (new Rfc2253Parser(rdnString)).parseRdn(this);
}

RFC 2253

javax.naming.ldap.LdapName

Parameters:

rdnString - The non-null and non-empty RFC2253 formatted string.

Throws:

InvalidNameException - If a syntax error occurs during parsing of the rdnString.

 public Rdn(Rdn rdn) {
        entries = new ArrayList(rdn.entries.size());
        entries.addAll(rdn.entries);
}

rdn

Parameters:

rdn - The non-null Rdn to be copied.

 public Rdn(String type,
    Object value) throws InvalidNameException {
        if (value == null) {
            throw new NullPointerException("Cannot set value to null");
        }
        if (type.equals("") || isEmptyValue(value)) {
            throw new InvalidNameException(
                "type or value cannot be empty, type:" + type +
                " value:" + value);
        }
        entries = new ArrayList(DEFAULT_SIZE);
        put(type, value);
}

RFC 2253

Parameters:

type - The non-null and non-empty string attribute type.

value - The non-null and non-empty attribute value.

Throws:

InvalidNameException - If type/value cannot be used to construct a valid RDN.

Also see:

toString()

Method from javax.naming.ldap.Rdn Summary:
compareTo, equals, escapeValue, getType, getValue, hashCode, put, size, sort, toAttributes, toString, unescapeValue

Methods from java.lang.Object:
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method from javax.naming.ldap.Rdn Detail:
public int compareTo(Object obj) { if (!(obj instanceof Rdn)) { throw new ClassCastException("The obj is not a Rdn"); } if (obj == this) { return 0; } Rdn that = (Rdn) obj; int minSize = Math.min(entries.size(), that.entries.size()); for (int i = 0; i < minSize; i++) { // Compare a single pair of type/value pairs. int diff = ((RdnEntry) entries.get(i)).compareTo( that.entries.get(i)); if (diff != 0) { return diff; } } return (entries.size() - that.entries.size()); // longer RDN wins } Compares this Rdn with the specified Object for order. Returns a negative integer, zero, or a positive integer as this Rdn is less than, equal to, or greater than the given Object. If obj is null or not an instance of Rdn, ClassCastException is thrown. The attribute type and value pairs of the RDNs are lined up against each other and compared lexicographically. The order of components in multi-valued Rdns (such as "ou=Sales+cn=Bob") is not significant.
public boolean equals(Object obj) { if (obj == this) { return true; } if (!(obj instanceof Rdn)) { return false; } Rdn that = (Rdn) obj; if (entries.size() != that.size()) { return false; } for (int i = 0; i < entries.size(); i++) { if (!entries.get(i).equals(that.entries.get(i))) { return false; } } return true; } Compares the specified Object with this Rdn for equality. Returns true if the given object is also a Rdn and the two Rdns represent the same attribute type and value mappings. The order of components in multi-valued Rdns (such as "ou=Sales+cn=Bob") is not significant. Type and value equalilty matching is done as below: The types are compared for equality with their case ignored. String values with different but equivalent usage of quoting, escaping, or UTF8-hex-encoding are considered equal. The case of the values is ignored during the comparison. If obj is null or not an instance of Rdn, false is returned.
public static String escapeValue(Object val) { return (val instanceof byte[]) ? escapeBinaryValue((byte[])val) : escapeStringValue((String)val); } Given the value of an attribute, returns a string escaped according to the rules specified in RFC 2253. For example, if the val is "Sue, Grabbit and Runn", the escaped value returned by this method is "Sue\, Grabbit and Runn". A string value is represented as a String and binary value as a byte array.
public String getType() { return ((RdnEntry) entries.get(0)).getType(); } Retrieves one of this Rdn's type. This is a convenience method for obtaining the type, when the RDN contains a single type and value mapping, which is the common RDN usage. For a multi-valued RDN, the type/value pairs have no specific order defined on them. In that case, this method returns type of one of the type/value pairs. The getValue() method returns the value corresponding to the type returned by this method.
public Object getValue() { return ((RdnEntry) entries.get(0)).getValue(); } Retrieves one of this Rdn's value. This is a convenience method for obtaining the value, when the RDN contains a single type and value mapping, which is the common RDN usage. For a multi-valued RDN, this method returns value corresponding to the type returned by getType() method.
public int hashCode() { // Sum up the hash codes of the components. int hash = 0; // For each type/value pair... for (int i = 0; i < entries.size(); i++) { hash += entries.get(i).hashCode(); } return hash; } Returns the hash code of this RDN. Two RDNs that are equal (according to the equals method) will have the same hash code.
Rdn put(String type, Object value) { // create new Entry RdnEntry newEntry = new RdnEntry(); newEntry.type = type; if (value instanceof byte[]) { // clone the byte array newEntry.value = ((byte[]) value).clone(); } else { newEntry.value = value; } entries.add(newEntry); return this; }
public int size() { return entries.size(); } Retrieves the number of attribute type/value pairs in this Rdn.
void sort() { if (entries.size() > 1) { Collections.sort(entries); } }
public Attributes toAttributes() { Attributes attrs = new BasicAttributes(true); for (int i = 0; i < entries.size(); i++) { RdnEntry entry = (RdnEntry) entries.get(i); Attribute attr = attrs.put(entry.getType(), entry.getValue()); if (attr != null) { attr.add(entry.getValue()); attrs.put(attr); } } return attrs; } Retrieves the Attributes view of the type/value mappings contained in this Rdn.
public String toString() { StringBuilder builder = new StringBuilder(); int size = entries.size(); if (size > 0) { builder.append(entries.get(0)); } for (int next = 1; next < size; next++) { builder.append('+'); builder.append(entries.get(next)); } return builder.toString(); } Returns this Rdn as a string represented in a format defined by RFC 2253 and described in the class description for LdapName .
public static Object unescapeValue(String val) { char[] chars = val.toCharArray(); int beg = 0; int end = chars.length; // Trim off leading and trailing whitespace. while ((beg < end) && isWhitespace(chars[beg])) { ++beg; } while ((beg < end) && isWhitespace(chars[end - 1])) { --end; } // Add back the trailing whitespace with a preceeding '\' // (escaped or unescaped) that was taken off in the above // loop. Whether or not to retain this whitespace is decided below. if (end != chars.length && (beg < end) && chars[end - 1] == '\\') { end++; } if (beg >= end) { return ""; } if (chars[beg] == '#') { // Value is binary (eg: "#CEB1DF80"). return decodeHexPairs(chars, ++beg, end); } // Trim off quotes. if ((chars[beg] == '\"') && (chars[end - 1] == '\"')) { ++beg; --end; } StringBuilder builder = new StringBuilder(end - beg); int esc = -1; // index of the last escaped character for (int i = beg; i < end; i++) { if ((chars[i] == '\\') && (i + 1 < end)) { if (!Character.isLetterOrDigit(chars[i + 1])) { ++i; // skip backslash builder.append(chars[i]); // snarf escaped char esc = i; } else { // Convert hex-encoded UTF-8 to 16-bit chars. byte[] utf8 = getUtf8Octets(chars, i, end); if (utf8.length > 0) { try { builder.append(new String(utf8, "UTF8")); } catch (java.io.UnsupportedEncodingException e) { // shouldn't happen } i += utf8.length * 3 - 1; } else { // no utf8 bytes available, invalid DN // '/' has no meaning, throw exception throw new IllegalArgumentException( "Not a valid attribute string value:" + val + ",improper usage of backslash"); } } } else { builder.append(chars[i]); // snarf unescaped char } } // Get rid of the unescaped trailing whitespace with the // preceeding '\' character that was previously added back. int len = builder.length(); if (isWhitespace(builder.charAt(len - 1)) && esc != (end - 1)) { builder.setLength(len - 1); } return builder.toString(); } Given an attribute value string formated according to the rules specified in RFC 2253, returns the unformated value. Escapes and quotes are stripped away, and hex-encoded UTF-8 is converted to equivalent UTF-16 characters. Returns a string value as a String, and a binary value as a byte array. Legal and illegal values are defined in RFC 2253. This method is generous in accepting the values and does not catch all illegal values. Therefore, passing in an illegal value might not necessarily trigger an `IllegalArgumentException`.

Method from javax.naming.ldap.Rdn Detail:

 public int compareTo(Object obj) {
        if (!(obj instanceof Rdn)) {
            throw new ClassCastException("The obj is not a Rdn");
        }
        if (obj == this) {
            return 0;
        }
        Rdn that = (Rdn) obj;
        int minSize = Math.min(entries.size(), that.entries.size());
        for (int i = 0; i <  minSize; i++) {
            // Compare a single pair of type/value pairs.
            int diff = ((RdnEntry) entries.get(i)).compareTo(
                                        that.entries.get(i));
            if (diff != 0) {
                return diff;
            }
        }
        return (entries.size() - that.entries.size());  // longer RDN wins
}

If obj is null or not an instance of Rdn, ClassCastException is thrown.

The attribute type and value pairs of the RDNs are lined up against each other and compared lexicographically. The order of components in multi-valued Rdns (such as "ou=Sales+cn=Bob") is not significant.

 public boolean equals(Object obj) {
        if (obj == this) {
            return true;
        }
        if (!(obj instanceof Rdn)) {
            return false;
        }
        Rdn that = (Rdn) obj;
        if (entries.size() != that.size()) {
            return false;
        }
        for (int i = 0; i <  entries.size(); i++) {
            if (!entries.get(i).equals(that.entries.get(i))) {
                return false;
            }
        }
        return true;
}

Type and value equalilty matching is done as below:

The types are compared for equality with their case ignored.
String values with different but equivalent usage of quoting, escaping, or UTF8-hex-encoding are considered equal. The case of the values is ignored during the comparison.

If obj is null or not an instance of Rdn, false is returned.

 public static String escapeValue(Object val) {
        return (val instanceof byte[])
                ? escapeBinaryValue((byte[])val)
                : escapeStringValue((String)val);
}

RFC 2253

For example, if the val is "Sue, Grabbit and Runn", the escaped value returned by this method is "Sue\, Grabbit and Runn".

A string value is represented as a String and binary value as a byte array.

 public String getType() {
        return ((RdnEntry) entries.get(0)).getType();
}

For a multi-valued RDN, the type/value pairs have no specific order defined on them. In that case, this method returns type of one of the type/value pairs. The getValue() method returns the value corresponding to the type returned by this method.

 public Object getValue() {
        return ((RdnEntry) entries.get(0)).getValue();
}

For a multi-valued RDN, this method returns value corresponding to the type returned by getType() method.

 public int hashCode() {
        // Sum up the hash codes of the components.
        int hash = 0;
        // For each type/value pair...
        for (int i = 0; i <  entries.size(); i++) {
            hash += entries.get(i).hashCode();
        }
        return hash;
}

Returns the hash code of this RDN. Two RDNs that are equal (according to the equals method) will have the same hash code.

 Rdn put(String type,
    Object value) {
        // create new Entry
        RdnEntry newEntry = new RdnEntry();
        newEntry.type =  type;
        if (value instanceof byte[]) {  // clone the byte array
            newEntry.value = ((byte[]) value).clone();
        } else {
            newEntry.value = value;
        }
        entries.add(newEntry);
        return this;
}

 public int size() {
        return entries.size();
}

Retrieves the number of attribute type/value pairs in this Rdn.

  void sort() {
        if (entries.size()  > 1) {
            Collections.sort(entries);
        }
}

 public Attributes toAttributes() {
        Attributes attrs = new BasicAttributes(true);
        for (int i = 0; i <  entries.size(); i++) {
            RdnEntry entry = (RdnEntry) entries.get(i);
            Attribute attr = attrs.put(entry.getType(), entry.getValue());
            if (attr != null) {
                attr.add(entry.getValue());
                attrs.put(attr);
            }
        }
        return attrs;
}

Attributes

 public String toString() {
        StringBuilder builder = new StringBuilder();
        int size = entries.size();
        if (size  > 0) {
            builder.append(entries.get(0));
        }
        for (int next = 1; next <  size; next++) {
            builder.append('+');
            builder.append(entries.get(next));
        }
        return builder.toString();
}

RFC 2253

LdapName

 public static Object unescapeValue(String val) {
            char[] chars = val.toCharArray();
            int beg = 0;
            int end = chars.length;
            // Trim off leading and trailing whitespace.
            while ((beg <  end) && isWhitespace(chars[beg])) {
                ++beg;
            }
            while ((beg <  end) && isWhitespace(chars[end - 1])) {
                --end;
            }
            // Add back the trailing whitespace with a preceeding '\'
            // (escaped or unescaped) that was taken off in the above
            // loop. Whether or not to retain this whitespace is decided below.
            if (end != chars.length &&
                    (beg <  end) &&
                    chars[end - 1] == '\\') {
                end++;
            }
            if (beg  >= end) {
                return "";
            }
            if (chars[beg] == '#') {
                // Value is binary (eg: "#CEB1DF80").
                return decodeHexPairs(chars, ++beg, end);
            }
            // Trim off quotes.
            if ((chars[beg] == '\"') && (chars[end - 1] == '\"')) {
                ++beg;
                --end;
            }
            StringBuilder builder = new StringBuilder(end - beg);
            int esc = -1; // index of the last escaped character
            for (int i = beg; i <  end; i++) {
                if ((chars[i] == '\\') && (i + 1 <  end)) {
                    if (!Character.isLetterOrDigit(chars[i + 1])) {
                        ++i;                            // skip backslash
                        builder.append(chars[i]);       // snarf escaped char
                        esc = i;
                    } else {
                        // Convert hex-encoded UTF-8 to 16-bit chars.
                        byte[] utf8 = getUtf8Octets(chars, i, end);
                        if (utf8.length  > 0) {
                            try {
                                builder.append(new String(utf8, "UTF8"));
                            } catch (java.io.UnsupportedEncodingException e) {
                                // shouldn't happen
                            }
                            i += utf8.length * 3 - 1;
                        } else { // no utf8 bytes available, invalid DN
                            // '/' has no meaning, throw exception
                            throw new IllegalArgumentException(
                                "Not a valid attribute string value:" +
                                val + ",improper usage of backslash");
                        }
                    }
                } else {
                    builder.append(chars[i]);   // snarf unescaped char
                }
            }
            // Get rid of the unescaped trailing whitespace with the
            // preceeding '\' character that was previously added back.
            int len = builder.length();
            if (isWhitespace(builder.charAt(len - 1)) && esc != (end - 1)) {
                builder.setLength(len - 1);
            }
            return builder.toString();
}

RFC 2253

Legal and illegal values are defined in RFC 2253. This method is generous in accepting the values and does not catch all illegal values. Therefore, passing in an illegal value might not necessarily trigger an IllegalArgumentException.