Syntax Error when using Arrays.asList with array shortcut declaration

Question

Can someone explain why this expression is OK

TestClass[] a = {new TestClass("a")};
public List<TestClass> tall = Arrays.asList( a );

but this one is rejected by the compiler with a "Syntax error"

public List<TestClass> tall = Arrays.asList( {new TestClass("a")} );

Is shortcut syntax for declaring arrays only allowed on the right side of an array declaration?

Answer 1

With the exception of an explicit array initialization (eg, TestClass[] a = {new TestClass("a")}; ), you cannot use the {} notation for an array literal without calling the new operator.

So either explicitly call the new operator:

public List<TestClass> tall = 
    Arrays.asList( new TestClass[] {new TestClass("a")} );

Or better yet, use Arrays.asList 's varags notation, and drop the array initialization completely:

public List<TestClass> tall = Arrays.asList(new TestClass("a"));