53 *
54 * <p>If not specified, the Namespace URI is set to {@link
55 * javax.xml.XMLConstants#NULL_NS_URI XMLConstants.NULL_NS_URI}.
56 * If not specified, the prefix is set to {@link
57 * javax.xml.XMLConstants#DEFAULT_NS_PREFIX
58 * XMLConstants.DEFAULT_NS_PREFIX}.</p>
59 *
60 * <p><code>QName</code> is immutable.</p>
61 *
62 * @author <a href="mailto:Jeff.Suttor@Sun.com">Jeff Suttor</a>
63 * @see <a href="http://www.w3.org/TR/xmlschema-2/#QName">
64 * XML Schema Part2: Datatypes specification</a>
65 * @see <a href="http://www.w3.org/TR/REC-xml-names/#ns-qualnames">
66 * Namespaces in XML</a>
67 * @see <a href="http://www.w3.org/XML/xml-names-19990114-errata">
68 * Namespaces in XML Errata</a>
69 * @since 1.5
70 */
71
72 public class QName implements Serializable {
73
74 /**
75 * <p>Stream Unique Identifier.</p>
76 *
77 * <p>Due to a historical defect, QName was released with multiple
78 * serialVersionUID values even though its serialization was the
79 * same.</p>
80 *
81 * <p>To workaround this issue, serialVersionUID is set with either
82 * a default value or a compatibility value. To use the
83 * compatibility value, set the system property:</p>
84 *
85 * <code>com.sun.xml.namespace.QName.useCompatibleSerialVersionUID=1.0</code>
86 *
87 * <p>This workaround was inspired by classes in the javax.management
88 * package, e.g. ObjectName, etc.
89 * See CR6267224 for original defect report.</p>
90 */
91 private static final long serialVersionUID;
92 /**
93 * <p>Default <code>serialVersionUID</code> value.</p>
94 */
95 private static final long defaultSerialVersionUID = -9120448754896609940L;
96 /**
97 * <p>Compatibility <code>serialVersionUID</code> value.</p>
98 */
99 private static final long compatibleSerialVersionUID = 4418622981026545151L;
100 /**
101 * <p>Flag to use default or campatible serialVersionUID.</p>
102 */
103 private static boolean useDefaultSerialVersionUID = true;
104 static {
105 try {
106 // use a privileged block as reading a system property
107 String valueUseCompatibleSerialVersionUID = SecuritySupport.getSystemProperty(
108 "com.sun.xml.namespace.QName.useCompatibleSerialVersionUID");
109
110 useDefaultSerialVersionUID = (valueUseCompatibleSerialVersionUID != null
111 && valueUseCompatibleSerialVersionUID.equals("1.0")) ? false : true;
112 } catch (Exception exception) {
113 // use default if any Exceptions
114 useDefaultSerialVersionUID = true;
115 }
116
117 // set serialVersionUID to desired value
118 if (useDefaultSerialVersionUID) {
119 serialVersionUID = defaultSerialVersionUID;
120 } else {
121 serialVersionUID = compatibleSerialVersionUID;
122 }
123 }
124
125 /**
126 * <p>Namespace URI of this <code>QName</code>.</p>
127 */
128 private final String namespaceURI;
129
130 /**
131 * <p>local part of this <code>QName</code>.</p>
132 */
133 private final String localPart;
134
135 /**
136 * <p>prefix of this <code>QName</code>.</p>
137 */
138 private final String prefix;
139
140 /**
141 * <p><code>QName</code> constructor specifying the Namespace URI
142 * and local part.</p>
143 *
|
53 *
54 * <p>If not specified, the Namespace URI is set to {@link
55 * javax.xml.XMLConstants#NULL_NS_URI XMLConstants.NULL_NS_URI}.
56 * If not specified, the prefix is set to {@link
57 * javax.xml.XMLConstants#DEFAULT_NS_PREFIX
58 * XMLConstants.DEFAULT_NS_PREFIX}.</p>
59 *
60 * <p><code>QName</code> is immutable.</p>
61 *
62 * @author <a href="mailto:Jeff.Suttor@Sun.com">Jeff Suttor</a>
63 * @see <a href="http://www.w3.org/TR/xmlschema-2/#QName">
64 * XML Schema Part2: Datatypes specification</a>
65 * @see <a href="http://www.w3.org/TR/REC-xml-names/#ns-qualnames">
66 * Namespaces in XML</a>
67 * @see <a href="http://www.w3.org/XML/xml-names-19990114-errata">
68 * Namespaces in XML Errata</a>
69 * @since 1.5
70 */
71
72 public class QName implements Serializable {
73 // tests show that the ID is the same from JDK 1.5 through JDK 9
74 private static final long serialVersionUID = -9120448754896609940L;
75
76 /**
77 * <p>Namespace URI of this <code>QName</code>.</p>
78 */
79 private final String namespaceURI;
80
81 /**
82 * <p>local part of this <code>QName</code>.</p>
83 */
84 private final String localPart;
85
86 /**
87 * <p>prefix of this <code>QName</code>.</p>
88 */
89 private final String prefix;
90
91 /**
92 * <p><code>QName</code> constructor specifying the Namespace URI
93 * and local part.</p>
94 *
|