diff options
Diffstat (limited to 'docs/adk15ProgGuideDB/varargs.adoc')
| -rw-r--r-- | docs/adk15ProgGuideDB/varargs.adoc | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/docs/adk15ProgGuideDB/varargs.adoc b/docs/adk15ProgGuideDB/varargs.adoc index fe1500c1f..bf644ace3 100644 --- a/docs/adk15ProgGuideDB/varargs.adoc +++ b/docs/adk15ProgGuideDB/varargs.adoc @@ -7,6 +7,7 @@ Java 5 (and hence AspectJ 5) allows you to specify methods that take a variable number of arguments of a specified type. This is achieved using an ellipsis (...) in the method signature as shown: +[source, java] .... public void foo(int i, String... strings) { } @@ -21,6 +22,7 @@ A _varargs_ method may be called with zero or more arguments in the variable argument position. For example, given the definition of `foo` above, the following calls are all legal: +[source, java] .... foo(5); foo(5,"One String"); @@ -31,6 +33,7 @@ foo(3,"One String","Two Strings","Three Strings"); A _varargs_ parameter is treated as an array within the defining member. So in the body of `foo` we could write for example: +[source, java] .... public void foo(int i, String... strings) { String[] someStrings = strings; @@ -41,6 +44,7 @@ public void foo(int i, String... strings) { One consequence of this treatment of a varargs parameter as an array is that you can also call a varargs method with an array: +[source, java] .... foo(7,new String[] {"One String","Two Strings"}); .... @@ -63,6 +67,7 @@ annotations (xref:annotations.adoc#signaturePatterns[Signature Patterns]), that `ConstructorPattern` are extended to allow a `varargs` pattern in the last argument position of a method or constructor signature. +[source, text] .... FormalsPattern := '..' (',' FormalsPatternAfterDotDot)? | OptionalParensTypePattern (',' FormalsPattern)* | @@ -93,6 +98,7 @@ initialization(org.xyz.*.new((Foo || Goo)...)):: A variable argument parameter and an array parameter are treated as distinct signature elements, so given the method definitions: +[source, java] .... void foo(String...); void bar(String[]); @@ -110,6 +116,7 @@ array type, as discussed in the introduction to this section. We follow the same convention when binding a varargs parameter via the `args` pointcut designator. Given a method +[source, java] .... public void foo(int i, String... strings) { } @@ -123,6 +130,7 @@ syntax within an args pointcut designator - so you _cannot_ write Binding of a varargs parameter in an advice statement is straightforward: +[source, java] .... before(int i, String[] ss) : call(* foo(int,String...)) && args(i,ss) { // varargs String... argument is accessible in advice body through ss |