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Java example source code file (fieldType.cpp)

This example Java source code file (fieldType.cpp) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

basictype, check_, fieldarrayinfo, fieldtype::is_valid_array_signature, fieldtype\:\:get_array_info, fieldtype\:\:skip_optional_size, t_byte, t_char, t_double, t_float, t_int, t_long, t_object

The fieldType.cpp Java example source code

/*
 * Copyright (c) 1997, 2011, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 *
 */

#include "precompiled.hpp"
#include "classfile/systemDictionary.hpp"
#include "memory/oopFactory.hpp"
#include "oops/oop.inline.hpp"
#include "oops/typeArrayKlass.hpp"
#include "runtime/fieldType.hpp"
#include "runtime/signature.hpp"

void FieldType::skip_optional_size(Symbol* signature, int* index) {
  jchar c = signature->byte_at(*index);
  while (c >= '0' && c <= '9') {
    *index = *index + 1;
    c = signature->byte_at(*index);
  }
}

BasicType FieldType::basic_type(Symbol* signature) {
  return char2type(signature->byte_at(0));
}

// Check if it is a valid array signature
bool FieldType::is_valid_array_signature(Symbol* sig) {
  assert(sig->utf8_length() > 1, "this should already have been checked");
  assert(sig->byte_at(0) == '[', "this should already have been checked");
  // The first character is already checked
  int i = 1;
  int len = sig->utf8_length();
  // First skip all '['s
  while(i < len - 1 && sig->byte_at(i) == '[') i++;

  // Check type
  switch(sig->byte_at(i)) {
    case 'B': // T_BYTE
    case 'C': // T_CHAR
    case 'D': // T_DOUBLE
    case 'F': // T_FLOAT
    case 'I': // T_INT
    case 'J': // T_LONG
    case 'S': // T_SHORT
    case 'Z': // T_BOOLEAN
      // If it is an array, the type is the last character
      return (i + 1 == len);
    case 'L':
      // If it is an object, the last character must be a ';'
      return sig->byte_at(len - 1) == ';';
  }

  return false;
}


BasicType FieldType::get_array_info(Symbol* signature, FieldArrayInfo& fd, TRAPS) {
  assert(basic_type(signature) == T_ARRAY, "must be array");
  int index = 1;
  int dim   = 1;
  skip_optional_size(signature, &index);
  while (signature->byte_at(index) == '[') {
    index++;
    dim++;
    skip_optional_size(signature, &index);
  }
  ResourceMark rm;
  char *element = signature->as_C_string() + index;
  BasicType element_type = char2type(element[0]);
  if (element_type == T_OBJECT) {
    int len = (int)strlen(element);
    assert(element[len-1] == ';', "last char should be a semicolon");
    element[len-1] = '\0';        // chop off semicolon
    fd._object_key = SymbolTable::new_symbol(element + 1, CHECK_(T_BYTE));
  }
  // Pass dimension back to caller
  fd._dimension = dim;
  return element_type;
}

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