/*
* Copyright (c) 1997, 1998, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
/*
* @test
* @bug 4030173 4071548
* @summary Verify correct conversion of non-string arguments in string concatenation.
* @author maddox
*
* @compile StringConversion.java
* @run main StringConversion
*/
class FooBar {
public String toString(){
return null;
}
}
public class StringConversion {
static void check(int testid, String have, String expect)
throws Exception {
if ((have == null && have != expect) ||
(have != null && !have.equals(expect))) {
String msg =
"TEST " + testid + ": HAVE \"" +
have + "\" EXPECT \"" + expect + "\"";
System.out.println("StringConversion: " + msg);
throw new Exception(msg);
}
}
public static void main(String[] args) throws Exception {
String s;
String n = null;
Object o = null;
FooBar m = new FooBar();
// Null reference must be converted to "null"
// Conversion will be done by 'StringBuffer.append'.
s = "foo" + n;
check(11, s, "foonull");
s = n + "bar";
check(12, s, "nullbar");
s = "foo" + o;
check(13, s, "foonull");
s = o + "bar";
check(14, s, "nullbar");
// Conversion will be done by 'String.valueOf'.
s = "" + n;
check(21, s, "null");
s = n + "";
check(22, s, "null");
s = "" + o;
check(23, s, "null");
s = o + "";
check(24, s, "null");
// Null 'toString' result must be converted to "null"
// Conversion will be done by 'StringBuffer.append'.
s = "foo" + m;
check(31, s, "foonull");
s = m + "bar";
check(32, s, "nullbar");
// Conversion will be done by 'String.valueOf'.
s = "" + m;
check(43, s, "null");
s = m + "";
check(44, s, "null");
// A character array must be converted as if by
// 'toString', i.e., it is treated as an 'Object'.
s = "polymorph";
char[] ca = {'i', 's', 'm'};
check(51, s + ca, s + ca.toString());
check(52, ca + s, ca.toString() + s);
System.out.println("OK");
}
}