Java tutorial
/* * Copyright (c) 1995 - 2008 Sun Microsystems, Inc. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * - Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * - Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * - Neither the name of Sun Microsystems nor the names of its * contributors may be used to endorse or promote products derived * from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ import static java.lang.System.out; import java.lang.reflect.Array; import java.lang.reflect.Constructor; import java.lang.reflect.InvocationTargetException; import java.util.Arrays; import java.util.regex.Matcher; import java.util.regex.Pattern; public class ArrayCreator { private static String s = "java.math.BigInteger bi[] = { 123, 234, 345 }"; private static Pattern p = Pattern.compile("^\\s*(\\S+)\\s*\\w+\\[\\].*\\{\\s*([^}]+)\\s*\\}"); public static void main(String... args) { Matcher m = p.matcher(s); if (m.find()) { String cName = m.group(1); String[] cVals = m.group(2).split("[\\s,]+"); int n = cVals.length; try { Class<?> c = Class.forName(cName); Object o = Array.newInstance(c, n); for (int i = 0; i < n; i++) { String v = cVals[i]; Constructor ctor = c.getConstructor(String.class); Object val = ctor.newInstance(v); Array.set(o, i, val); } Object[] oo = (Object[]) o; out.format("%s[] = %s%n", cName, Arrays.toString(oo)); // production code should handle these exceptions more gracefully } catch (ClassNotFoundException x) { x.printStackTrace(); } catch (NoSuchMethodException x) { x.printStackTrace(); } catch (IllegalAccessException x) { x.printStackTrace(); } catch (InstantiationException x) { x.printStackTrace(); } catch (InvocationTargetException x) { x.printStackTrace(); } } } }