RTTI improvements for Java backend. io.write/3 works for some simple types

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RTTI improvements for Java backend.  io.write/3 works for some simple types
(builtin types and non-existential d.u. types).

compiler/mlds_to_java.m:
        Fix problem with cyclic RTTI definitions.  Initialisers could refer to
        other RTTI structures which weren't yet allocated, leading to fields
        being null.  The fix is to allocate all top-level RTTI objects first
        and initialise in a second phase.

java/runtime/DuExistInfo.java:
java/runtime/DuExistLocn.java:
java/runtime/DuFunctorDesc.java:
java/runtime/EnumFunctorDesc.java:
java/runtime/ForeignEnumFunctorDesc.java:
java/runtime/TypeClassConstraint.java:
java/runtime/TypeClassDeclStruct.java:
java/runtime/TypeClassId.java:
java/runtime/TypeCtorInfo_Struct.java:
java/runtime/TypeInfo_Struct.java:
        Separate constructors into constructors for the initial allocation,
        and an `init' method to fill in the fields.

java/runtime/MethodPtr.java:
        Use variadic method support to simplify semidet_call_* and
        result_call_* in rtti_implementation.m.

library/builtin.m:
        Make Java definitions of builtin.unify/2 and builtin.compare/3 call
        rtti_implementation.generic_unify and generic_compare.

library/private_builtin.m:
        Add missing MR_TYPECTOR_REP_FOREIGN_ENUM{,_USEREQ} constants
        for C# and Java.

library/rtti_implementation.m:
        Fix and add missing Java versions of many foreign_procs.

        Add more attributes to foreign_procs.

        Clean up the code a bit (fewer casts and ^ field access functions).

README.Java:
        Bump Java version requirement to J2SE 1.5 or higher.

java/runtime/DuExistInfo.java

@@ -15,7 +15,11 @@ public class DuExistInfo {
 	public /* final */ mercury.runtime.TypeClassConstraint[]
 		exist_constraints;
 
-	public DuExistInfo(int typeinfos_plain, int typeinfos_in_tci, int tcis,
+	public DuExistInfo()
+	{
+	}
+
+	public void init(int typeinfos_plain, int typeinfos_in_tci, int tcis,
 		mercury.runtime.DuExistLocn[] typeinfo_locns,
 		mercury.runtime.TypeClassConstraint constraints[])
 	{

java/runtime/DuExistLocn.java

@@ -11,6 +11,7 @@ package mercury.runtime;
 public class DuExistLocn {
 	public int exist_arg_num;
 	public int exist_offset_in_tci;
+
 	public DuExistLocn(int arg_num, int offset_in_tci) {
 		exist_arg_num = arg_num;
 		exist_offset_in_tci = offset_in_tci;

java/runtime/DuFunctorDesc.java

@@ -21,7 +21,11 @@ public class DuFunctorDesc {
 	public /*final*/ java.lang.String[] du_functor_arg_names;
 	public /*final*/ mercury.runtime.DuExistInfo du_functor_exist_info;
 
-	public DuFunctorDesc(java.lang.String functor_name, int orig_arity,
+	public DuFunctorDesc()
+	{
+	}
+
+	public void init(java.lang.String functor_name, int orig_arity,
 		int arg_type_contains_var, int sectag_locn, int primary,
 		int secondary, int ordinal,
 		// XXX why do we need to use Object here?

java/runtime/EnumFunctorDesc.java

@@ -11,7 +11,10 @@ public class EnumFunctorDesc {
 	public java.lang.String enum_functor_name;
 	public int              enum_functor_ordinal;
 
-	public EnumFunctorDesc(String name, int ordinal) {
+	public EnumFunctorDesc() {
+	}
+
+	public void init(String name, int ordinal) {
 		enum_functor_name = name;
 		enum_functor_ordinal = ordinal;
 	}

java/runtime/ForeignEnumFunctorDesc.java

@@ -12,7 +12,10 @@ public class ForeignEnumFunctorDesc {
 	public int			foreign_enum_functor_ordinal;
 	public int			foreign_enum_functor_value;
 
-	public ForeignEnumFunctorDesc(String name, int ordinal, int value) {
+	public ForeignEnumFunctorDesc() {
+	}
+
+	public void init(String name, int ordinal, int value) {
 		foreign_enum_functor_name = name;
 		foreign_enum_functor_ordinal = ordinal;
 		foreign_enum_functor_value = value;

java/runtime/MethodPtr.java

@@ -10,6 +10,6 @@
 package mercury.runtime;
 
 public interface MethodPtr {
-	public abstract java.lang.Object call___0_0(java.lang.Object[] args); 
+	public abstract java.lang.Object call___0_0(java.lang.Object... args);
 }
 

java/runtime/TypeClassConstraint.java

@@ -13,20 +13,11 @@ public class TypeClassConstraint {
 	public TypeClassDeclStruct	tc_constr_type_class;
 	public PseudoTypeInfo		tc_constr_arg_ptis[];
 
-	public TypeClassConstraint(TypeClassDeclStruct type_class)
+	public TypeClassConstraint()
 	{
-		tc_constr_type_class = type_class;
-		tc_constr_arg_ptis = new PseudoTypeInfo[] {};
 	}
 
-	public TypeClassConstraint(TypeClassDeclStruct type_class,
-		PseudoTypeInfo[] ptis)
-	{
-		tc_constr_type_class = type_class;
-		tc_constr_arg_ptis = ptis;
-	}
-
-	public TypeClassConstraint(TypeClassDeclStruct type_class,
+	public void init(TypeClassDeclStruct type_class,
 		// XXX Object[] should be mercury.runtime.PseudoTypeInfo[],
 		//     but mlds_to_java.m generates Object[] since
 		//     init_array/1 doesn't give type info
@@ -38,47 +29,4 @@ public class TypeClassConstraint {
 			tc_constr_arg_ptis[i] = (PseudoTypeInfo) ptis[i];
 		}
 	}
-
-	public TypeClassConstraint(TypeClassDeclStruct type_class,
-		PseudoTypeInfo pti1)
-	{
-		tc_constr_type_class = type_class;
-		tc_constr_arg_ptis = new PseudoTypeInfo[] { pti1 };
-	}
-
-	public TypeClassConstraint(TypeClassDeclStruct type_class,
-		PseudoTypeInfo pti1, PseudoTypeInfo pti2)
-	{
-		tc_constr_type_class = type_class;
-		tc_constr_arg_ptis = new PseudoTypeInfo[] { pti1, pti2 };
-	}
-
-	public TypeClassConstraint(TypeClassDeclStruct type_class,
-		PseudoTypeInfo pti1, PseudoTypeInfo pti2,
-		PseudoTypeInfo pti3)
-	{
-		tc_constr_type_class = type_class;
-		tc_constr_arg_ptis = new PseudoTypeInfo[] { pti1, pti2, pti3 };
-	}
-
-	public TypeClassConstraint(TypeClassDeclStruct type_class,
-		PseudoTypeInfo pti1, PseudoTypeInfo pti2,
-		PseudoTypeInfo pti3, PseudoTypeInfo pti4)
-	{
-		tc_constr_type_class = type_class;
-		tc_constr_arg_ptis = new PseudoTypeInfo[]
-			{ pti1, pti2, pti3, pti4 };
-	}
-
-	public TypeClassConstraint(TypeClassDeclStruct type_class,
-		PseudoTypeInfo pti1, PseudoTypeInfo pti2,
-		PseudoTypeInfo pti3, PseudoTypeInfo pti4,
-		PseudoTypeInfo pti5)
-	{
-		tc_constr_type_class = type_class;
-		tc_constr_arg_ptis = new PseudoTypeInfo[] {
-			pti1, pti2, pti3, pti4, pti5 };
-	}
-
-	// XXX type classes with arity > 5 not supported
 }

java/runtime/TypeClassDeclStruct.java

@@ -16,7 +16,11 @@ public class TypeClassDeclStruct {
 	public int			tc_decl_num_supers; // redundant
 	public TypeClassConstraint	tc_decl_supers;
 
-	public TypeClassDeclStruct(TypeClassId id, int version_number,
+	public TypeClassDeclStruct()
+	{
+	}
+
+	public void init(TypeClassId id, int version_number,
 		int num_supers, TypeClassConstraint supers)
 	{
 		tc_decl_id = id;

java/runtime/TypeClassId.java

@@ -18,7 +18,11 @@ public class TypeClassId {
 	public String[]			tc_id_var_names;
 	public TypeClassMethod[]	tc_id_methods;
 
-	public TypeClassId(String module_name, String name, int arity,
+	public TypeClassId()
+	{
+	}
+
+	public void init(String module_name, String name, int arity,
 		int num_type_vars, int num_methods,
 		String[] var_names, TypeClassMethod[] methods)
 	{

java/runtime/TypeCtorInfo_Struct.java

@@ -25,7 +25,11 @@ public class TypeCtorInfo_Struct extends PseudoTypeInfo {
 	public /* short */ int 			type_ctor_flags;
 	public int[]              		type_functor_number_map;
 
-	public TypeCtorInfo_Struct(
+	public TypeCtorInfo_Struct()
+	{
+	}
+
+	public void init(
 			int type_arity, int version, int num_ptags, int rep,
 			Object unify_proc, Object compare_proc, 
 			String module, String name,

java/runtime/TypeInfo_Struct.java

@@ -11,18 +11,15 @@ public class TypeInfo_Struct extends PseudoTypeInfo {
 	public TypeCtorInfo_Struct type_ctor;
 	public PseudoTypeInfo args[];
 
+	public TypeInfo_Struct()
+	{
+	}
+
 	public TypeInfo_Struct(TypeCtorInfo_Struct tc)
 	{
 		type_ctor = tc;
 	}
 
-    	// raw constructor
-	public TypeInfo_Struct(TypeCtorInfo_Struct tc, PseudoTypeInfo... as)
-	{
-		type_ctor = tc;
-		args = as;
-	}
-
 	// copy constructor
 	// XXX Rather than invoking this constructor, and allocating a new
 	//     type_info object on the heap, we should generate code which
@@ -33,42 +30,44 @@ public class TypeInfo_Struct extends PseudoTypeInfo {
 		args = ti.args;
 	}
 
-	// XXX "as" should have type PseudoTypeInfo[],
-	//     but mlds_to_java.m uses Object[]
-	//     because init_array/1 does not store the type.
-	public TypeInfo_Struct(TypeCtorInfo_Struct tc, int arity, Object[] as)
+	public void init(TypeCtorInfo_Struct tc, PseudoTypeInfo[] as)
 	{
-		assert arity == as.length;
-
-		type_ctor = tc;
-		args = new PseudoTypeInfo[as.length];
-		for (int i = 0; i < as.length; i++) {
-			args[i] = (PseudoTypeInfo) as[i];
-		}
+	    type_ctor = tc;
+	    args = as;
 	}
 
 	// XXX "as" should have type PseudoTypeInfo[],
 	//     but mlds_to_java.m uses Object[]
 	//     because init_array/1 does not store the type.
-	public TypeInfo_Struct(TypeCtorInfo_Struct tc, Object[] as)
+	public void init(TypeCtorInfo_Struct tc, int arity, Object[] as)
 	{
-		type_ctor = tc;
-		args = new PseudoTypeInfo[as.length];
+		assert arity == as.length;
+
+		init(tc, as);
+	}
+
+	// XXX "as" should have type PseudoTypeInfo[],
+	//     but mlds_to_java.m uses Object[]
+	//     because init_array/1 does not store the type.
+	public void init(TypeCtorInfo_Struct tc, Object[] as)
+	{
+		PseudoTypeInfo[] ptis = new PseudoTypeInfo[as.length];
 		for (int i = 0; i < as.length; i++) {
-			args[i] = (PseudoTypeInfo) as[i];
+			ptis[i] = (PseudoTypeInfo) as[i];
 		}
+                init(tc, ptis);
 	}
 
 	// XXX untested guess
 	public TypeInfo_Struct(TypeInfo_Struct ti, int arity, Object... as)
 	{
-		this(ti.type_ctor, arity, as);
+		init(ti.type_ctor, arity, as);
 	}
 
 	// XXX untested guess
 	public TypeInfo_Struct(TypeInfo_Struct ti, Object... as)
 	{
-		this(ti.type_ctor, as);
+		init(ti.type_ctor, as);
 	}
 
 	// XXX a temp hack just to get things to run