The String class

As with all other Java object types, java.lang.String is mapped to a proxy class, java_lang_String. This proxy class has a few special features:

• A C++ constructor that takes a char* parameter (assumes UTF-8 encoding):

  String s1("abc");
  

• An overloaded assignment operator, which allows you to assign a string in any of the following ways:

  String s2 = "xyz";
  String s3 = String("xyz");
  String s4 = new_String("xyz");
  

• A str method that returns a char* (UTF-8 format). The return value is automatically freed when the String from which it was obtained goes out of scope. The following code segment prints “xyz” to standard output:

  String s2 = "xyz";
  char* s2Str = s2.str();
  cout << s2.str();
  

• A strcpy method that returns a char* (UTF-8 format). The return value is a copy, which is not automatically freed. You must free it explicitly using the delete[] operator. The following code segment prints “xyz” to standard output, then frees the memory associated with s2Str.

  String s2 = "xyz";
  char* s2Str = s2.strcpy();
  cout << s2Str;
  delete[] s2Str;
  

To pass a String constant in a parameter of type Object, you can use an explicit String constructor, as illustrated in the following code segment:

java_util_HashMap map = new_java_util_HashMap();
map.put(String("abc"), String("xyz"));