The Java Language Specification, Third Edition

EXPRESSIONS Compound Assignment Operators 15.26.2
class RightHandSideThrow extends RuntimeException { }
class IllustrateCompoundArrayAssignment {
static String[] strings = { "Simon", "Garfunkel" };
static double[] doubles = { Math.E, Math.PI };
static String[] stringsThrow() {
throw new ArrayReferenceThrow();
}
static double[] doublesThrow() {
throw new ArrayReferenceThrow();
}
static int indexThrow() { throw new IndexThrow(); }
static String stringThrow() {
throw new RightHandSideThrow();
}
static double doubleThrow() {
throw new RightHandSideThrow();
}
static String name(Object q) {
String sq = q.getClass().getName();
int k = sq.lastIndexOf('.');
return (k < 0) ? sq : sq.substring(k+1);
}
static void testEight(String[] x, double[] z, int j) {
String sx = (x == null) ? "null" : "Strings";
String sz = (z == null) ? "null" : "doubles";
System.out.println();
try {
System.out.print(sx + "[throw]+=throw => ");
x[indexThrow()] += stringThrow();
System.out.println("Okay!");
} catch (Throwable e) { System.out.println(name(e)); }
try {
System.out.print(sz + "[throw]+=throw => ");
z[indexThrow()] += doubleThrow();
System.out.println("Okay!");
} catch (Throwable e) { System.out.println(name(e)); }
try {
System.out.print(sx + "[throw]+=\"heh\" => ");
x[indexThrow()] += "heh";
System.out.println("Okay!");
} catch (Throwable e) { System.out.println(name(e)); }
try {
DRAFT
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