154 * current thread, it is first initialized to the value returned
155 * by an invocation of the {@link #initialValue} method.
156 *
157 * @return the current thread's value of this thread-local
158 */
159 public T get() {
160 Thread t = Thread.currentThread();
161 ThreadLocalMap map = getMap(t);
162 if (map != null) {
163 ThreadLocalMap.Entry e = map.getEntry(this);
164 if (e != null) {
165 @SuppressWarnings("unchecked")
166 T result = (T)e.value;
167 return result;
168 }
169 }
170 return setInitialValue();
171 }
172
173 /**
174 * Variant of set() to establish initialValue. Used instead
175 * of set() in case user has overridden the set() method.
176 *
177 * @return the initial value
178 */
179 private T setInitialValue() {
180 T value = initialValue();
181 Thread t = Thread.currentThread();
182 ThreadLocalMap map = getMap(t);
183 if (map != null)
184 map.set(this, value);
185 else
186 createMap(t, value);
187 return value;
188 }
189
190 /**
191 * Sets the current thread's copy of this thread-local variable
192 * to the specified value. Most subclasses will have no need to
193 * override this method, relying solely on the {@link #initialValue}
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154 * current thread, it is first initialized to the value returned
155 * by an invocation of the {@link #initialValue} method.
156 *
157 * @return the current thread's value of this thread-local
158 */
159 public T get() {
160 Thread t = Thread.currentThread();
161 ThreadLocalMap map = getMap(t);
162 if (map != null) {
163 ThreadLocalMap.Entry e = map.getEntry(this);
164 if (e != null) {
165 @SuppressWarnings("unchecked")
166 T result = (T)e.value;
167 return result;
168 }
169 }
170 return setInitialValue();
171 }
172
173 /**
174 * Returns the value in the current thread's copy of this
175 * thread-local variable. If the variable has no value for the
176 * current thread, null is returned and no value is initialized.
177 *
178 * @return the current thread's value of this thread-local or null
179 */
180 T getIfPresent() {
181 Thread t = Thread.currentThread();
182 ThreadLocalMap map = getMap(t);
183 if (map != null) {
184 ThreadLocalMap.Entry e = map.getEntry(this);
185 if (e != null) {
186 @SuppressWarnings("unchecked")
187 T result = (T)e.value;
188 return result;
189 }
190 }
191 return null;
192 }
193
194 /**
195 * Variant of set() to establish initialValue. Used instead
196 * of set() in case user has overridden the set() method.
197 *
198 * @return the initial value
199 */
200 private T setInitialValue() {
201 T value = initialValue();
202 Thread t = Thread.currentThread();
203 ThreadLocalMap map = getMap(t);
204 if (map != null)
205 map.set(this, value);
206 else
207 createMap(t, value);
208 return value;
209 }
210
211 /**
212 * Sets the current thread's copy of this thread-local variable
213 * to the specified value. Most subclasses will have no need to
214 * override this method, relying solely on the {@link #initialValue}
|