class JvmBytecode::ConstantPool

Public Class Methods

new() click to toggle source
# File lib/jvm_bytecode/constant_pool.rb, line 5
def initialize
  @constants = []
end

Public Instance Methods

add(const) click to toggle source
# File lib/jvm_bytecode/constant_pool.rb, line 53
def add(const)
  @constants.push(const).length
end
add_class(name) click to toggle source
# File lib/jvm_bytecode/constant_pool.rb, line 22
def add_class(name)
  add(Constants::Class.new(index_or_utf8(name)))
end
add_method_ref(class_index, name_and_type_index) click to toggle source
# File lib/jvm_bytecode/constant_pool.rb, line 32
def add_method_ref(class_index, name_and_type_index)
  add(Constants::MethodRef.new(class_index, name_and_type_index))
end
add_name_and_type(name, descriptor) click to toggle source
# File lib/jvm_bytecode/constant_pool.rb, line 26
def add_name_and_type(name, descriptor)
  add(
    Constants::NameAndType.new(index_or_utf8(name), index_or_utf8(descriptor))
  )
end
bytecode() click to toggle source
# File lib/jvm_bytecode/constant_pool.rb, line 61
def bytecode
  @constants.join_bytecodes { @constants.length + 1 }
end
class_index(name) click to toggle source
# File lib/jvm_bytecode/constant_pool.rb, line 36
def class_index(name)
  name_index = utf8(name)
  
  index = nil
  each_constants_of Constants::Class.tag do |klass, i|
    index = i if klass.name_index == name_index
  end

  index || raise(Errors::ConstantError, "Class constant named \"#{name}\" doesn't exist")
end
constant(index) click to toggle source
# File lib/jvm_bytecode/constant_pool.rb, line 9
def constant(index)
  @constants[index - 1]
end
decode(io) click to toggle source
# File lib/jvm_bytecode/constant_pool.rb, line 65
def decode(io)
  entries = io.read(2).unpack('S>').first - 1

  @constants.clear
  entries.times do
    tag = io.read(1).unpack('C').first
    @constants << Constants::Constant.fetch(tag).decode(io)
  end
end
each_constants_of(tag) { |const, i + 1| ... } click to toggle source
# File lib/jvm_bytecode/constant_pool.rb, line 47
def each_constants_of(tag)
  @constants.each.with_index do |const, i|
    yield const, i + 1 if const.class.tag == tag
  end
end
index_or_utf8(v) click to toggle source
# File lib/jvm_bytecode/constant_pool.rb, line 57
def index_or_utf8(v)
  v.is_a?(String) ? utf8(v) : v.to_i
end
to_hash() click to toggle source
# File lib/jvm_bytecode/constant_pool.rb, line 75
def to_hash
  @constants.map.with_index do |const, i|
    { 
      index: i + 1,
      type: const.class.name.split('::').last.gsub('Constant', '')
    }.merge(const.to_hash)
  end
end
utf8(str) click to toggle source
# File lib/jvm_bytecode/constant_pool.rb, line 13
def utf8(str)
  index = nil
  each_constants_of Constants::Utf8.tag do |utf8, i|
    index = i if utf8.to_s == str
  end

  index || add(Constants::Utf8.new(str))
end