82 lines
2.8 KiB
Java
82 lines
2.8 KiB
Java
/*
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* This program and the accompanying materials
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* are made available under the terms of the Eclipse Public License v1.0
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* which accompanies this distribution, and is available at
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* http://www.eclipse.org/legal/epl-v10.html.
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*
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* This file is a derivative of code released by the University of
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* California under the terms listed below.
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*
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* WALA JDT Frontend is Copyright (c) 2008 The Regents of the
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* University of California (Regents). Provided that this notice and
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* the following two paragraphs are included in any distribution of
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* Refinement Analysis Tools or its derivative work, Regents agrees
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* not to assert any of Regents' copyright rights in Refinement
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* Analysis Tools against recipient for recipient's reproduction,
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* preparation of derivative works, public display, public
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* performance, distribution or sublicensing of Refinement Analysis
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* Tools and derivative works, in source code and object code form.
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* This agreement not to assert does not confer, by implication,
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* estoppel, or otherwise any license or rights in any intellectual
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* property of Regents, including, but not limited to, any patents
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* of Regents or Regents' employees.
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*
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* IN NO EVENT SHALL REGENTS BE LIABLE TO ANY PARTY FOR DIRECT,
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* INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES,
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* INCLUDING LOST PROFITS, ARISING OUT OF THE USE OF THIS SOFTWARE
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* AND ITS DOCUMENTATION, EVEN IF REGENTS HAS BEEN ADVISED OF THE
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* POSSIBILITY OF SUCH DAMAGE.
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*
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* REGENTS SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, BUT NOT
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* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
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* FOR A PARTICULAR PURPOSE AND FURTHER DISCLAIMS ANY STATUTORY
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* WARRANTY OF NON-INFRINGEMENT. THE SOFTWARE AND ACCOMPANYING
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* DOCUMENTATION, IF ANY, PROVIDED HEREUNDER IS PROVIDED "AS
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* IS". REGENTS HAS NO OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT,
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* UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
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*/
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package javaonepointfive;
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import java.util.ArrayList;
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public class Wildcards {
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public void printCollection(ArrayList<?> c) {
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// for (Object e : c) {
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// for (Iterator tmp = c.iterator(); tmp.hasNext(); ) {
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// Object e = tmp.next();
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Object e = c.get(0);
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System.out.println(e);
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// }
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}
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public void printCollection1(ArrayList<? extends Object> c) {
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Object e = c.get(0);
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System.out.println(e);
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}
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public void printCollection2(ArrayList<? extends String> c) {
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String e = c.get(0);
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System.out.println(e);
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}
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public static void main(String args[]) {
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(new Wildcards()).doit();
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}
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private void doit() {
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ArrayList<String> e = new ArrayList<>();
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e.add("hello");
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e.add("goodbye");
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printCollection(e);
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printCollection1(e);
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printCollection2(e);
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ArrayList<Integer> e3 = new ArrayList<>();
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e3.add(new Integer(123));
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e3.add(new Integer(42));
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printCollection(e3);
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printCollection1(e3);
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}
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}
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