50
51 /**
52 * Subclass of <code>ResourceBundle</code> which mimics
53 * <code>ListResourceBundle</code>, but provides more hooks
54 * for specialized subclass behavior. For general description,
55 * see {@link java.util.ListResourceBundle}.
56 * <p>
57 * This class leaves handleGetObject non-final, and
58 * adds a method createMap which allows subclasses to
59 * use specialized Map implementations.
60 */
61 public abstract class OpenListResourceBundle extends ResourceBundle {
62 /**
63 * Sole constructor. (For invocation by subclass constructors, typically
64 * implicit.)
65 */
66 protected OpenListResourceBundle() {
67 }
68
69 // Implements java.util.ResourceBundle.handleGetObject; inherits javadoc specification.
70 public Object handleGetObject(String key) {
71 if (key == null) {
72 throw new NullPointerException();
73 }
74
75 loadLookupTablesIfNecessary();
76 return lookup.get(key); // this class ignores locales
77 }
78
79 /**
80 * Implementation of ResourceBundle.getKeys.
81 */
82 public Enumeration<String> getKeys() {
83 ResourceBundle parent = this.parent;
84 return new ResourceBundleEnumeration(handleGetKeys(),
85 (parent != null) ? parent.getKeys() : null);
86 }
87
88 /**
89 * Returns a set of keys provided in this resource bundle
90 */
91 public Set<String> handleGetKeys() {
92 loadLookupTablesIfNecessary();
93
94 return lookup.keySet();
95 }
96
97 @Override
98 public Set<String> keySet() {
99 if (keyset != null) {
100 return keyset;
101 }
102 Set<String> ks = new HashSet<>();
103 ks.addAll(handleGetKeys());
104 if (parent != null) {
105 ks.addAll(parent.keySet());
106 }
107 synchronized (this) {
108 if (keyset == null) {
109 keyset = ks;
110 }
111 }
112 return keyset;
113 }
114
115 /**
116 * Returns the parent bundle
117 */
118 public OpenListResourceBundle getParent() {
119 return (OpenListResourceBundle)parent;
120 }
121
122 /**
123 * See ListResourceBundle class description.
124 */
125 abstract protected Object[][] getContents();
126
127 /**
128 * Load lookup tables if they haven't been loaded already.
129 */
130 void loadLookupTablesIfNecessary() {
131 if (lookup == null) {
132 loadLookup();
133 }
134 }
135
136 /**
137 * We lazily load the lookup hashtable. This function does the
138 * loading.
139 */
140 private void loadLookup() {
141 Object[][] contents = getContents();
142 Map<String, Object> temp = createMap(contents.length);
143 for (int i = 0; i < contents.length; ++i) {
144 // key must be non-null String, value must be non-null
145 String key = (String) contents[i][0];
146 Object value = contents[i][1];
147 if (key == null || value == null) {
148 throw new NullPointerException();
149 }
150 temp.put(key, value);
151 }
152 synchronized (this) {
153 if (lookup == null) {
154 lookup = temp;
155 }
156 }
157 }
158
159 /**
160 * Lets subclasses provide specialized Map implementations.
161 * Default uses HashMap.
162 */
163 protected Map<String, Object> createMap(int size) {
164 return new HashMap<>(size);
165 }
166
167 private volatile Map<String, Object> lookup = null;
168 private volatile Set<String> keyset;
169 }
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50
51 /**
52 * Subclass of <code>ResourceBundle</code> which mimics
53 * <code>ListResourceBundle</code>, but provides more hooks
54 * for specialized subclass behavior. For general description,
55 * see {@link java.util.ListResourceBundle}.
56 * <p>
57 * This class leaves handleGetObject non-final, and
58 * adds a method createMap which allows subclasses to
59 * use specialized Map implementations.
60 */
61 public abstract class OpenListResourceBundle extends ResourceBundle {
62 /**
63 * Sole constructor. (For invocation by subclass constructors, typically
64 * implicit.)
65 */
66 protected OpenListResourceBundle() {
67 }
68
69 // Implements java.util.ResourceBundle.handleGetObject; inherits javadoc specification.
70 @Override
71 public Object handleGetObject(String key) {
72 if (key == null) {
73 throw new NullPointerException();
74 }
75
76 loadLookupTablesIfNecessary();
77 return lookup.get(key); // this class ignores locales
78 }
79
80 /**
81 * Implementation of ResourceBundle.getKeys.
82 */
83 @Override
84 public Enumeration<String> getKeys() {
85 ResourceBundle parent = this.parent;
86 return new ResourceBundleEnumeration(handleGetKeys(),
87 (parent != null) ? parent.getKeys() : null);
88 }
89
90 /**
91 * Returns a set of keys provided in this resource bundle,
92 * including no parents.
93 */
94 public Set<String> handleGetKeys() {
95 loadLookupTablesIfNecessary();
96
97 return lookup.keySet();
98 }
99
100 @Override
101 public Set<String> keySet() {
102 if (keyset != null) {
103 return keyset;
104 }
105 Set<String> ks = createSet();
106 ks.addAll(handleGetKeys());
107 if (parent != null) {
108 ks.addAll(parent.keySet());
109 }
110 synchronized (this) {
111 if (keyset == null) {
112 keyset = ks;
113 }
114 }
115 return keyset;
116 }
117
118 /**
119 * See ListResourceBundle class description.
120 */
121 abstract protected Object[][] getContents();
122
123 /**
124 * Load lookup tables if they haven't been loaded already.
125 */
126 void loadLookupTablesIfNecessary() {
127 if (lookup == null) {
128 loadLookup();
129 }
130 }
131
132 /**
133 * We lazily load the lookup hashtable. This function does the
134 * loading.
135 */
136 private void loadLookup() {
137 Object[][] contents = getContents();
138 Map<String, Object> temp = createMap(contents.length);
139 for (int i = 0; i < contents.length; ++i) {
140 // key must be non-null String, value must be non-null
141 String key = (String) contents[i][0];
142 Object value = contents[i][1];
143 if (key == null || value == null) {
144 throw new NullPointerException();
145 }
146 temp.put(key, value);
147 }
148 synchronized (this) {
149 if (lookup == null) {
150 lookup = temp;
151 }
152 }
153 }
154
155 /**
156 * Lets subclasses provide specialized Map implementations.
157 * Default uses HashMap.
158 */
159 protected <K, V> Map<K, V> createMap(int size) {
160 return new HashMap<>(size);
161 }
162
163 protected <E> Set<E> createSet() {
164 return new HashSet<>();
165 }
166
167 private volatile Map<String, Object> lookup = null;
168 private volatile Set<String> keyset;
169 }
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