Java std::vector improvements for types that do not have a default constructor.

The std::vector wrappers have been changed to work by default for elements that are
not default insertable, i.e. have no default constructor. This has been achieved by
not wrapping:

  vector(size_type n);

Previously the above had to be ignored via %ignore.

If the above constructor is still required it can be added back in again via %extend:

  %extend std::vector {
    vector(size_type count) { return new std::vector< T >(count); }
  }

Alternatively, the following wrapped constructor could be used as it provides near-enough
equivalent functionality:

  vector(jint count, const value_type& value);

The equivalent change to std::list has also been made (std::list
wrappers were not in the previous release [3.0.12] though).

CHANGES.current

@@ -7,6 +7,30 @@ the issue number to the end of the URL: https://github.com/swig/swig/issues/
 Version 4.0.0 (in progress)
 ===========================
 
+2019-02-28: wsfulton
+            [Java] std::vector improvements for types that do not have a default constructor.
+
+            The std::vector wrappers have been changed to work by default for elements that are
+            not default insertable, i.e. have no default constructor. This has been achieved by
+            not wrapping:
+
+              vector(size_type n);
+
+            Previously the above had to be ignored via %ignore.
+
+            If the above constructor is still required it can be added back in again via %extend:
+
+              %extend std::vector {
+                vector(size_type count) { return new std::vector< T >(count); }
+              }
+
+            Alternatively, the following wrapped constructor could be used as it provides near-enough
+            equivalent functionality:
+
+              vector(jint count, const value_type& value);
+
+            *** POTENTIAL INCOMPATIBILITY ***
+
 2019-02-25: wsfulton
             [Python] Fix compile errors wrapping overloaded functions/constructors where a vararg
             function is declared after a non-vararg function.

Examples/test-suite/common.mk

@@ -407,6 +407,7 @@ CPP_TEST_CASES += \
 	static_array_member \
 	static_const_member \
 	static_const_member_2 \
+	stl_no_default_constructor \
 	string_constants \
 	struct_initialization_cpp \
 	struct_value \

Examples/test-suite/java/li_std_list_runme.java

@@ -53,7 +53,7 @@ public class li_std_list_runme {
     if (v1.size() != 0) throw new RuntimeException("v1 test (16) failed");
     if (v1.remove(Integer.valueOf(456))) throw new RuntimeException("v1 test (17) failed");
 
-    if (new IntList(3).size() != 3) throw new RuntimeException("constructor initial size test failed");
+    if (new IntList(3, 0).size() != 3) throw new RuntimeException("constructor initial size test failed");
     for (int n : new IntList(10, 999))
       if (n != 999) throw new RuntimeException("constructor initialization with value failed");
     for (int n : new IntList(new IntList(10, 999)))

Examples/test-suite/java/li_std_vector_runme.java

@@ -54,7 +54,7 @@ public class li_std_vector_runme {
     if (v1.size() != 0) throw new RuntimeException("v1 test (16) failed");
     if (v1.remove(Integer.valueOf(456))) throw new RuntimeException("v1 test (17) failed");
 
-    if (new IntVector(3).size() != 3) throw new RuntimeException("constructor initial size test failed");
+    if (new IntVector(3, 0).size() != 3) throw new RuntimeException("constructor initial size test failed");
     for (int n : new IntVector(10, 999))
       if (n != 999) throw new RuntimeException("constructor initialization with value failed");
     for (int n : new IntVector(new IntVector(10, 999)))

Examples/test-suite/stl_no_default_constructor.i

@@ -0,0 +1,19 @@
+%module stl_no_default_constructor
+
+%include <stl.i>
+
+%inline %{
+struct NoDefaultCtor {
+  int value;
+  NoDefaultCtor(int i) : value(i) {}
+};
+%}
+
+#if defined(SWIGCSHARP) || defined(SWIGJAVA) || defined(SWIGD)
+%template(VectorNoDefaultCtor) std::vector<NoDefaultCtor>;
+#endif
+
+#if defined(SWIGJAVA)
+%include <std_list.i>
+%template(ListNoDefaultCtor) std::list<NoDefaultCtor>;
+#endif

Lib/java/std_list.i

@@ -198,11 +198,6 @@ namespace std {
 
     %extend {
       %fragment("SWIG_ListSize");
-      list(jint count) throw (std::out_of_range) {
-        if (count < 0)
-          throw std::out_of_range("list count must be positive");
-        return new std::list<T>(static_cast<std::list<T>::size_type>(count));
-      }
 
       list(jint count, const T &value) throw (std::out_of_range) {
         if (count < 0)

Lib/java/std_vector.i

@@ -94,11 +94,6 @@ SWIGINTERN jint SWIG_VectorSize(size_t size) {
     void clear();
     %extend {
       %fragment("SWIG_VectorSize");
-      vector(jint count) throw (std::out_of_range) {
-        if (count < 0)
-          throw std::out_of_range("vector count must be positive");
-        return new std::vector< CTYPE >(static_cast<std::vector< CTYPE >::size_type>(count));
-      }
 
       vector(jint count, const CTYPE &value) throw (std::out_of_range) {
         if (count < 0)