improvement for class parser

.golangci.yml

@@ -1,14 +1,30 @@
 linters:
   disable-all: true
   enable:
-    - deadcode
+    - unused
     - errcheck
     - gosimple
     - govet
     - ineffassign
     - staticcheck
-    - structcheck
     - unused
-    - varcheck
     - gofmt
     - goconst
+    - misspell
+    - nolintlint
+    - tagliatelle
+linters-settings:
+  misspell:
+    locale: US
+  nolintlint:
+    allow-unused: false # report any unused nolint directives
+    require-explanation: false # don't require an explanation for nolint directives
+    require-specific: false # don't require nolint directives to be specific about which linter is being skipped
+  tagliatelle:
+    case:
+      rules:
+        json: snake
+        yaml: snake
+        xml: snake
+        form: snake
+        msgpack: snake

class/attribute_access.go

@@ -0,0 +1,22 @@
+package class
+
+type AttrAccessFlag uint16
+
+const (
+	AttrAccPublic       AttrAccessFlag = 0x0001 // Declared public; may be accessed from outside its package.
+	AttrAccPrivate      AttrAccessFlag = 0x0002 // Declared private; accessible only within the defining class and other classes belonging to the same nest (§5.4.4).
+	AttrAccProtected    AttrAccessFlag = 0x0004 // Declared protected; may be accessed within subclasses.
+	AttrAccStatic       AttrAccessFlag = 0x0008 // Declared static.
+	AttrAccFinal        AttrAccessFlag = 0x0010 // Declared final; must not be overridden (§5.4.5).
+	AttrAccSynchronized AttrAccessFlag = 0x0020 // Declared synchronized; invocation is wrapped by a monitor use.
+	AttrAccBridge       AttrAccessFlag = 0x0040 // A bridge method, generated by the compiler.
+	AttrAccVarargs      AttrAccessFlag = 0x0080 // Declared with variable number of arguments.
+	AttrAccNative       AttrAccessFlag = 0x0100 // Declared native; implemented in a language other than the Java programming language.
+	AttrAccAbstract     AttrAccessFlag = 0x0400 // Declared abstract; no implementation is provided.
+	AttrAccStrict       AttrAccessFlag = 0x0800 // In a class file whose major version number is at least 46 and at most 60: Declared strictfp.
+	AttrAccSynthetic    AttrAccessFlag = 0x1000 // Declared synthetic; not present in the source code.
+)
+
+func (aaf AttrAccessFlag) HasAccessFlag(flag AttrAccessFlag) bool {
+	return (flag & aaf) == flag
+}

class/class_access.go

@@ -0,0 +1,50 @@
+package class
+
+import (
+	"encoding/binary"
+	"fmt"
+	"github.com/phith0n/zkar/commons"
+)
+
+type ClassAccessFlag uint16
+
+const (
+	ClassAccPublic     ClassAccessFlag = 0x0001 // Declared public; may be accessed from outside its package.
+	ClassAccPrivate    ClassAccessFlag = 0x0002 // Marked private in source.
+	ClassAccProtected  ClassAccessFlag = 0x0004 // Marked protected in source.
+	ClassAccStatic     ClassAccessFlag = 0x0008 // Marked or implicitly static in source.
+	ClassAccFinal      ClassAccessFlag = 0x0010 // Declared final; no subclasses allowed.
+	ClassAccSuper      ClassAccessFlag = 0x0020 // Treat superclass methods specially when invoked by the invokespecial instruction.
+	ClassAccInterface  ClassAccessFlag = 0x0200 // Is an interface, not a class.
+	ClassAccAbstract   ClassAccessFlag = 0x0400 // Declared abstract; must not be instantiated.
+	ClassAccSynthetic  ClassAccessFlag = 0x1000 // Declared synthetic; not present in the source code.
+	ClassAccAnnotation ClassAccessFlag = 0x2000 // Declared as an annotation type.
+	ClassAccEnum       ClassAccessFlag = 0x4000 // Declared as an enum type.
+	ClassAccModule     ClassAccessFlag = 0x8000 // Is a module, not a class or interface.
+)
+
+func (caf ClassAccessFlag) HasAccessFlag(flag ClassAccessFlag) bool {
+	return (flag & caf) == flag
+}
+
+func (cf *ClassFile) readAccessFlag(stream *commons.Stream) error {
+	bs, err := stream.ReadN(2)
+	if err != nil {
+		return fmt.Errorf("read access flag failed, no enough data in the stream")
+	}
+
+	var i = binary.BigEndian.Uint16(bs)
+	cf.AccessFlag = ClassAccessFlag(i)
+
+	// check access flag valid
+	if cf.AccessFlag.HasAccessFlag(ClassAccFinal) && cf.AccessFlag.HasAccessFlag(ClassAccAbstract) {
+		return fmt.Errorf("ACC_FINAL and ACC_ABSTRACT are not able to set at the same time")
+	}
+
+	if cf.AccessFlag.HasAccessFlag(ClassAccAnnotation) && !cf.AccessFlag.HasAccessFlag(ClassAccInterface) {
+		return fmt.Errorf("if ACC_ANNOTATION is set, ACC_ANNOTATION must also be set")
+	}
+
+	// TODO: maybe need more check
+	return nil
+}

class/classfile.go

@@ -13,7 +13,7 @@ type ClassFile struct {
 	MinorVersion        uint16
 	MajorVersion        uint16
 	ConstantPool        []Constant
-	AccessFlag          uint16
+	AccessFlag          ClassAccessFlag
 	ThisClassIndex      uint16
 	SuperClassIndex     uint16
 	InterfaceIndexArray []uint16
@@ -29,7 +29,7 @@ func (cf *ClassFile) readHeader(stream *commons.Stream) error {
 	}
 
 	if !bytes.Equal(bs, []byte("\xCA\xFE\xBA\xBE")) {
-		return fmt.Errorf("magic number %v is not equal to CAFEBABE", hex.EncodeToString(bs))
+		return fmt.Errorf("magic number %v is not equal to 0xCAFEBABE", hex.EncodeToString(bs))
 	}
 
 	cf.MagicNumber = bs

class/constant.go

@@ -7,23 +7,23 @@ import (
 )
 
 const (
-	CONSTANT_UTF8_INFO            = 1
-	CONSTANT_INTEGER_INFO         = 3
-	CONSTANT_FLOAT_INFO           = 4
-	CONSTANT_LONG_INFO            = 5
-	CONSTANT_DOUBLE_INFO          = 6
-	CONSTANT_CLASS_INFO           = 7
-	CONSTANT_STRING_INGFO         = 8
-	CONSTANT_FIELD_REF_INFO       = 9
-	CONSTANT_METHOD_REF_INFO      = 10
-	CONSTANT_INTERFACE_METHOD_REF = 11
-	CONSTANT_NAME_AND_TYPE_INFO   = 12
-	CONSTANT_METHOD_HANDLE_INFO   = 15
-	CONSTANT_METHOD_TYPE_INFO     = 16
-	CONSTANT_DYNAMIC_INFO         = 17
-	CONSTANT_INVOKE_DYNAMIC_INFO  = 18
-	CONSTANT_MODULE_INFO          = 19
-	CONSTANT_PACKAGE_INFO         = 20
+	ConstantUtf8Info               = 1
+	ConstantIntegerInfo            = 3
+	ConstantFloatInfo              = 4
+	ConstantLongInfo               = 5
+	ConstantDoubleInfo             = 6
+	ConstantClassInfo              = 7
+	ConstantStringInfo             = 8
+	ConstantFieldRefInfo           = 9
+	ConstantMethodRefInfo          = 10
+	ConstantInterfaceMethodRefInfo = 11
+	ConstantNameAndTypeInfo        = 12
+	ConstantMethodHandleInfo       = 15
+	ConstantMethodTypeInfo         = 16
+	ConstantDynamicInfo            = 17
+	ConstantInvokeDynamicInfo      = 18
+	ConstantModuleInfo             = 19
+	ConstantPackageInfo            = 20
 )
 
 type Constant interface {
@@ -57,39 +57,39 @@ func (cf *ClassFile) readConstant(stream *commons.Stream) error {
 
 	var obj Constant
 	switch bs[0] {
-	case CONSTANT_UTF8_INFO:
+	case ConstantUtf8Info:
 		obj, err = cf.readConstantUTF8(stream)
-	case CONSTANT_INTEGER_INFO:
+	case ConstantIntegerInfo:
 		obj, err = cf.readConstantInteger(stream)
-	case CONSTANT_FLOAT_INFO:
+	case ConstantFloatInfo:
 		obj, err = cf.readConstantFloat(stream)
-	case CONSTANT_LONG_INFO:
+	case ConstantLongInfo:
 		obj, err = cf.readConstantLong(stream)
-	case CONSTANT_DOUBLE_INFO:
+	case ConstantDoubleInfo:
 		obj, err = cf.readConstantDouble(stream)
-	case CONSTANT_CLASS_INFO:
+	case ConstantClassInfo:
 		obj, err = cf.readConstantClass(stream)
-	case CONSTANT_STRING_INGFO:
+	case ConstantStringInfo:
 		obj, err = cf.readConstantString(stream)
-	case CONSTANT_FIELD_REF_INFO:
+	case ConstantFieldRefInfo:
 		obj, err = cf.readConstantFieldRef(stream)
-	case CONSTANT_METHOD_REF_INFO:
+	case ConstantMethodRefInfo:
 		obj, err = cf.readConstantMethodRef(stream)
-	case CONSTANT_INTERFACE_METHOD_REF:
+	case ConstantInterfaceMethodRefInfo:
 		obj, err = cf.readConstantInterfaceMethodRef(stream)
-	case CONSTANT_NAME_AND_TYPE_INFO:
+	case ConstantNameAndTypeInfo:
 		obj, err = cf.readConstantNameAndType(stream)
-	case CONSTANT_METHOD_HANDLE_INFO:
+	case ConstantMethodHandleInfo:
 		obj, err = cf.readConstantMethodHandle(stream)
-	case CONSTANT_METHOD_TYPE_INFO:
+	case ConstantMethodTypeInfo:
 		obj, err = cf.readConstantMethodType(stream)
-	case CONSTANT_DYNAMIC_INFO:
+	case ConstantDynamicInfo:
 		obj, err = cf.readConstantDynamic(stream)
-	case CONSTANT_INVOKE_DYNAMIC_INFO:
+	case ConstantInvokeDynamicInfo:
 		obj, err = cf.readConstantInvokeDynamic(stream)
-	case CONSTANT_MODULE_INFO:
+	case ConstantModuleInfo:
 		obj, err = cf.readConstantModule(stream)
-	case CONSTANT_PACKAGE_INFO:
+	case ConstantPackageInfo:
 		obj, err = cf.readConstantPackage(stream)
 	default:
 		err = fmt.Errorf("constant type %v doesn't exists", bs)

class/constant_class.go

@@ -11,7 +11,7 @@ type ConstantClass struct {
 }
 
 func (c *ConstantClass) ToBytes() []byte {
-	var bs = []byte{CONSTANT_CLASS_INFO}
+	var bs = []byte{ConstantClassInfo}
 	bs = append(bs, commons.NumberToBytes(c.NameIndex)...)
 	return bs
 }

class/constant_double.go

@@ -12,7 +12,7 @@ type ConstantDouble struct {
 }
 
 func (c *ConstantDouble) ToBytes() []byte {
-	var bs = []byte{CONSTANT_DOUBLE_INFO}
+	var bs = []byte{ConstantDoubleInfo}
 	bs = append(bs, commons.NumberToBytes(c.Double)...)
 	return bs
 }

class/constant_dynamic.go

@@ -12,7 +12,7 @@ type ConstantDynamic struct {
 }
 
 func (c *ConstantDynamic) ToBytes() []byte {
-	var bs = []byte{CONSTANT_DYNAMIC_INFO}
+	var bs = []byte{ConstantDynamicInfo}
 	bs = append(bs, commons.NumberToBytes(c.BootstrapMethodIndex)...)
 	bs = append(bs, commons.NumberToBytes(c.NameAndTypeIndex)...)
 	return bs

class/constant_fieldref.go

@@ -12,7 +12,7 @@ type ConstantFieldRef struct {
 }
 
 func (c *ConstantFieldRef) ToBytes() []byte {
-	var bs = []byte{CONSTANT_FIELD_REF_INFO}
+	var bs = []byte{ConstantFieldRefInfo}
 	bs = append(bs, commons.NumberToBytes(c.ClassIndex)...)
 	bs = append(bs, commons.NumberToBytes(c.NameAndTypeIndex)...)
 	return bs

class/constant_float.go

@@ -12,7 +12,7 @@ type ConstantFloat struct {
 }
 
 func (c *ConstantFloat) ToBytes() []byte {
-	var bs = []byte{CONSTANT_FLOAT_INFO}
+	var bs = []byte{ConstantFloatInfo}
 	bs = append(bs, commons.NumberToBytes(c.Float)...)
 	return bs
 }

class/constant_integer.go

@@ -11,7 +11,7 @@ type ConstantInteger struct {
 }
 
 func (c *ConstantInteger) ToBytes() []byte {
-	var bs = []byte{CONSTANT_INTEGER_INFO}
+	var bs = []byte{ConstantIntegerInfo}
 	bs = append(bs, commons.NumberToBytes(c.Integer)...)
 	return bs
 }

class/constant_invoke_dynamic.go

@@ -12,7 +12,7 @@ type ConstantInvokeDynamic struct {
 }
 
 func (c *ConstantInvokeDynamic) ToBytes() []byte {
-	var bs = []byte{CONSTANT_INVOKE_DYNAMIC_INFO}
+	var bs = []byte{ConstantInvokeDynamicInfo}
 	bs = append(bs, commons.NumberToBytes(c.BootstrapMethodIndex)...)
 	bs = append(bs, commons.NumberToBytes(c.NameAndTypeIndex)...)
 	return bs

class/constant_long.go

@@ -11,7 +11,7 @@ type ConstantLong struct {
 }
 
 func (c *ConstantLong) ToBytes() []byte {
-	var bs = []byte{CONSTANT_LONG_INFO}
+	var bs = []byte{ConstantLongInfo}
 	bs = append(bs, commons.NumberToBytes(c.Long)...)
 	return bs
 }

class/constant_method_handle.go

@@ -12,7 +12,7 @@ type ConstantMethodHandle struct {
 }
 
 func (c *ConstantMethodHandle) ToBytes() []byte {
-	var bs = []byte{CONSTANT_METHOD_HANDLE_INFO}
+	var bs = []byte{ConstantMethodHandleInfo}
 	bs = append(bs, c.ReferenceKind)
 	bs = append(bs, commons.NumberToBytes(c.ReferenceIndex)...)
 	return bs

class/constant_method_type.go

@@ -11,7 +11,7 @@ type ConstantMethodType struct {
 }
 
 func (c *ConstantMethodType) ToBytes() []byte {
-	var bs = []byte{CONSTANT_METHOD_TYPE_INFO}
+	var bs = []byte{ConstantMethodTypeInfo}
 	bs = append(bs, commons.NumberToBytes(c.DescriptorIndex)...)
 	return bs
 }

class/constant_methodref.go

@@ -12,7 +12,7 @@ type ConstantMethodRef struct {
 }
 
 func (c *ConstantMethodRef) ToBytes() []byte {
-	var bs = []byte{CONSTANT_METHOD_REF_INFO}
+	var bs = []byte{ConstantMethodRefInfo}
 	bs = append(bs, commons.NumberToBytes(c.ClassIndex)...)
 	bs = append(bs, commons.NumberToBytes(c.NameAndTypeIndex)...)
 	return bs

class/constant_module.go

@@ -11,7 +11,7 @@ type ConstantModule struct {
 }
 
 func (c *ConstantModule) ToBytes() []byte {
-	var bs = []byte{CONSTANT_MODULE_INFO}
+	var bs = []byte{ConstantModuleInfo}
 	bs = append(bs, commons.NumberToBytes(c.NameIndex)...)
 	return bs
 }

class/constant_nametype.go

@@ -12,7 +12,7 @@ type ConstantNameAndType struct {
 }
 
 func (c *ConstantNameAndType) ToBytes() []byte {
-	var bs = []byte{CONSTANT_NAME_AND_TYPE_INFO}
+	var bs = []byte{ConstantNameAndTypeInfo}
 	bs = append(bs, commons.NumberToBytes(c.NameIndex)...)
 	bs = append(bs, commons.NumberToBytes(c.DescriptorIndex)...)
 	return bs

class/constant_package.go

@@ -11,7 +11,7 @@ type ConstantPackage struct {
 }
 
 func (c *ConstantPackage) ToBytes() []byte {
-	var bs = []byte{CONSTANT_PACKAGE_INFO}
+	var bs = []byte{ConstantPackageInfo}
 	bs = append(bs, commons.NumberToBytes(c.NameIndex)...)
 	return bs
 }