Object subclass:#JavaClassReader

	instanceVariableNames:'inStream msb constants version majorVsn minorVsn constNeeds2Slots

		constSlot'

	classVariableNames:'Verbose ClassPath Silent'

	poolDictionaries:''

	category:'Java-Support'

!

!JavaClassReader  class methodsFor:'initialization'!

initialize

    Verbose := false. Silent := false.

    self initializeClassPath

    "

     JavaClassReader initialize

    "

!

initializeClassPath

    "

     JavaClassReader initializeClassPath

    "

!

initializeClassPath:aCollectionOfDirectoryPathNames

    ClassPath := aCollectionOfDirectoryPathNames

    "

     JavaClassReader initializeClassPath:#(

                        '/home/cg/java/'

                  )

    "

! !

!JavaClassReader  class methodsFor:'debugging'!

verbose:aBoolean

    Verbose := aBoolean

    "

     Java flushClasses.

     JavaClassReader verbose:true

     JavaClassReader verbose:false

    "

! !

!JavaClassReader  class methodsFor:'file reading'!

loadClass:aClassName

    "reads a class, installs and returns it.

     The classes string constants are resolved & <clinit> is called,

     if it implements it."

    |rslt|

    rslt := self loadClassLazy:aClassName ignoring:Set new.

    self postLoadActions.

    ^ rslt

    "

     JavaClassReader loadClass:'awt/Component'

     JavaClassReader loadClass:'awt/Button'

     JavaClassReader loadClass:'browser/AddButton'

     JavaClassReader loadClass:'java/lang/Object'

     JavaClassReader loadClass:'java/lang/AbstractMethodError'

     JavaClassReader loadClass:'java/lang/Thread'

    "

    "Created: 15.4.1996 / 14:58:53 / cg"

!

loadClassLazy:aClassName ignoring:classesBeingLoaded

    "private helper:

      reads a class, installs and returns it.

      The class is searched along the ClassPath.

     This is a partial load (to load other classes):

     - The classes stringConstants are not fixed to be JavaStrings 

       (i.e they are still ST-Strings).

     - The class is not initialized."

    |rslt clsName|

    (aClassName endsWith:';') ifTrue:[

        ('oops - loading of ' , aClassName , ' attempted') printNL.

self halt.

        ^ nil

    ].

    clsName := aClassName.

    (clsName includes:$.) ifTrue:[

        clsName := clsName copy replaceAll:$. by:$/

    ].

    (classesBeingLoaded includes:clsName) ifTrue:[

        ('oops - recursive load of ' , clsName , ' attempted') printNL.

"/ self halt.

        ^ JavaUnresolvedClassConstant fullName:clsName

    ].

    classesBeingLoaded add:clsName.

    ClassPath do:[:path |

        rslt := self loadFileLazy:(path , clsName , '.class')

                         ignoring:classesBeingLoaded.

        rslt notNil ifTrue:[^ rslt].

    ].

    ^ rslt

!

loadFile:aFilename

    "reads a class from aFilename, installs and returns it.

     The classes strings are fixed and its class-init function is called."

    self loadFileLazy:aFilename ignoring:(Set new).

    self postLoadActions

!

loadFileLazy:aFilename ignoring:classesBeingLoaded

    "reads a class from aFilename, installs and returns it.

     No strings are fixed and no class-init functions are called."

    |javaClass pool|

    javaClass := self readFile:aFilename ignoring:classesBeingLoaded.

    javaClass notNil ifTrue:[

        Java at:(javaClass fullName asSymbol) put:javaClass.

"/        javaClass resolveClassRefsIgnoring:classesBeingLoaded.

        classesBeingLoaded remove:javaClass fullName ifAbsent:nil.

"/        Smalltalk at:(javaClass fullName asSymbol) put:javaClass.

"/        Smalltalk changed.

    ].

    ^ javaClass

    "

     JavaClassReader loadFile:'/phys/ibm3/hotjava/classes/browser/AddButton.class'

     '/phys/ibm3/java/lib/java/lang' asFilename

        directoryContents do:[:nm |

            (nm endsWith:'.class') ifTrue:[

                ('/phys/ibm3/java/lib/java/lang/' , nm) printNL.

                JavaClassReader loadFile:'/phys/ibm3/java/lib/java/lang/' , nm

            ]

        ].

     '/phys/ibm3/java/lib/java/io' asFilename

        directoryContents do:[:nm |

            (nm endsWith:'.class') ifTrue:[

                ('/phys/ibm3/java/lib/java/io/' , nm) printNL.

                JavaClassReader loadFile:'/phys/ibm3/java/lib/java/io/' , nm

            ]

        ].

     '/phys/ibm3/java/lib/java/net' asFilename

        directoryContents do:[:nm |

            (nm endsWith:'.class') ifTrue:[

                ('/phys/ibm3/java/lib/java/net/' , nm) printNL.

                JavaClassReader loadFile:'/phys/ibm3/java/lib/java/net/' , nm

            ]

        ].

     '/phys/ibm3/java/lib/java/util' asFilename

        directoryContents do:[:nm |

            (nm endsWith:'.class') ifTrue:[

                ('/phys/ibm3/java/lib/java/util/' , nm) printNL.

                JavaClassReader loadFile:'/phys/ibm3/java/lib/java/util/' , nm

            ]

        ].

     '/phys/ibm3/java/lib/java/awt' asFilename

        directoryContents do:[:nm |

            (nm endsWith:'.class') ifTrue:[

                ('/phys/ibm3/java/lib/java/awt/' , nm) printNL.

                JavaClassReader loadFile:'/phys/ibm3/java/lib/java/awt/' , nm

            ]

        ].

     '/phys/ibm3/java/lib/java/applet' asFilename

        directoryContents do:[:nm |

            (nm endsWith:'.class') ifTrue:[

                ('/phys/ibm3/java/lib/java/applet/' , nm) printNL.

                JavaClassReader loadFile:'/phys/ibm3/java/lib/java/applet/' , nm

            ]

        ].

     JavaClassReader loadFile:'/phys/ibm3/java/lib/java/lang/AbstractMethodError.class'

     JavaClassReader loadFile:'/phys/ibm3/java/lib/java/lang/Thread.class'

    "

    "Created: 15.4.1996 / 14:58:53 / cg"

!

postLoadActions

    "Resolve all classes' string constants.

     Perform all class initialization functions (of those which are not

     yet initialized)."

    JavaUnresolvedStringConstant patchupStringConstants.

    Java allClassesDo:[:aJavaClass |

        aJavaClass resolveClassRefsIgnoring:Set new.

    ].

    Java allClassesDo:[:aJavaClass |

        aJavaClass isInitialized ifFalse:[

            aJavaClass classInit

        ]

    ]

!

readFile:aFilename ignoring:classesBeingLoaded

    "reads a class from aFilename and returns it.

     The JavaClass is NOT installed as global"

    |inStream retVal|

    Silent ifFalse:[

        'reading ' print. aFilename print. ' ...' printNL.

    ].

    inStream := aFilename asFilename readStream.

    inStream isNil ifTrue:['nil' printNL. ^ nil].

    retVal := self readStream:inStream ignoring:classesBeingLoaded.

    inStream close.

    Silent ifFalse:[

        '  ... loaded ' print. retVal displayString printNL.

    ].

    ^ retVal

    "Created: 15.4.1996 / 14:58:53 / cg"

!

readStream:aStream ignoring:classesBeingLoaded

    "reads a class from aStream and returns it.

     The JavaClass is not installed as global"

    ^ self new readStream:aStream ignoring:classesBeingLoaded

    "

     JavaClassReader readFile:'/phys/ibm3/hotjava/classes/browser/AddButton.class'

    "

    "Modified: 15.4.1996 / 15:01:30 / cg"

! !

!JavaClassReader methodsFor:'file reading'!

readClassFileIgnoring:classesbeingLoaded

    "reads a class from inStream and returns it.

     The JavaClass is not installed as global and its constants

     (especially strings) may not be fully resolved."

    |magic 

     access_flags this_class this_class_index super_class super_class_index

     realSuperClass this_class_ref existingSuperClass

     fields interfaces staticFields nStatic|

    "/

    "/ read magic, determine byte order

    "/

    msb := true.

    magic := self nextU4.

    magic = 16rCAFEBABE ifFalse:[

        magic = 16rBEBAFECA ifFalse:[

            self error:'not a java class file'.

            ^ nil

        ].

        msb := false.

        Verbose ifTrue:[Transcript showCR:'file is lsb'].

    ] ifTrue:[

        Verbose ifTrue:[Transcript showCR:'file is msb'].

    ].

    "/

    "/ get version

    "/

    version := self nextU4.

    majorVsn := (version bitShift:-16) bitAnd:16rFFFF.

    minorVsn := version bitAnd:16rFFFF.

    Verbose ifTrue:[Transcript show:'version = '; 

                               show:(majorVsn printString); 

                               show:'.';

                               showCR:(minorVsn printString)].

    "/

    "/ get constant pool

    "/

    self readConstantPool.

    "/

    "/ access flags

    "/

    access_flags := self nextU2.

    this_class_index := self nextU2.

    super_class_index := self nextU2.

"/    this_class_ref := constants at:this_class_index.

"/    this_class := JavaClass fullName:(this_class_ref fullName).

    super_class_index == 0 ifTrue:[

        super_class := nil

    ] ifFalse:[

        super_class := constants at:super_class_index.

        existingSuperClass := Java classNamed:super_class fullName.

        existingSuperClass notNil ifTrue:[

            super_class := existingSuperClass

        ] ifFalse:[

            (super_class isMemberOf:JavaUnresolvedClassConstant) ifTrue:[

                existingSuperClass := super_class resolve.

                existingSuperClass isNil ifTrue:[

                    super_class := self class 

                                        loadClassLazy:(super_class fullName)

                                        ignoring:classesbeingLoaded.

                ].

                super_class isNil ifTrue:[

                    self halt:('cannot find superclass: ' , super_class fullName).

                ]

            ].

        ].

    ].

    "/

    "/ get interfaces

    "/

    interfaces := self readInterfaces.

    "/

    "/ get fields

    "/

    fields := self readFieldInfofields.

    "/

    "/ create the fields as instVars

    "/ static fields are created as class-InstVars

    "/

    staticFields := fields select:[:f | f isStatic].

    nStatic := staticFields size.

    this_class_ref := constants at:this_class_index.

    nStatic ~~ 0 ifTrue:[

        fields := fields select:[:f | f isStatic not].

        this_class := JavaClass fullName:(this_class_ref fullName) numStatic:nStatic.

        JavaClass setInstanceVariableStringFromFields:staticFields in:this_class class.

        this_class setStaticFields:staticFields.

        this_class initializeStaticFields.

    ] ifFalse:[

        this_class := JavaClass fullName:(this_class_ref fullName).

    ].

    this_class setAccessFlags:access_flags.

    this_class setSuperclass:super_class.

    this_class setConstantPool:constants.

    this_class setFields:fields.

    "/

    "/ get methods

    "/

    self readMethodsFor:this_class.

    self readAttributesFor:this_class.

    ^ this_class

    "

     JavaClassReader readFile:'/phys/ibm3/hotjava/classes/browser/AddButton.class'

     JavaClassReader readFile:'/phys/ibm3/hotjava/classes/browser/Alignable.class'

     JavaClassReader verbose:true.

     JavaClassReader readFile:'/phys/ibm3/hotjava/classes/java/lang/ArithmeticException.class'

     JavaClassReader readFile:'/phys/ibm3/java/lib/java/lang/ArithmeticException.class'

    "

    "Created: 15.4.1996 / 15:02:47 / cg"

    "Modified: 15.4.1996 / 16:51:48 / cg"

!

readSourceFileAttributeFor:aJavaClass

    |attribute_length sourceFile_index sourceFile|

    attribute_length := self nextU4.

    sourceFile_index := self nextU2.

    sourceFile := constants at:sourceFile_index.

    aJavaClass setSourceFile:sourceFile.

    Verbose ifTrue:[Transcript show:'sourceFile: '; showCR:sourceFile].

    ^ true

    "

     JavaClassReader readFile:'/phys/ibm3/hotjava/classes/browser/AddButton.class'

     JavaClassReader readFile:'/phys/ibm3/hotjava/classes/browser/Alignable.class'

    "

    "Modified: 15.4.1996 / 15:33:28 / cg"

    "Created: 15.4.1996 / 15:40:17 / cg"

!

readStream:aStream ignoring:classesBeingLoaded

    "reads a class from aStream and returns it.

     The JavaClass is not installed as global"

    inStream := aStream.

    inStream binary.

    ^ self readClassFileIgnoring:classesBeingLoaded

    "

     JavaClassReader readFile:'/phys/ibm3/hotjava/classes/browser/AddButton.class'

    "

    "Created: 15.4.1996 / 15:00:55 / cg"

    "Modified: 15.4.1996 / 15:06:18 / cg"

! !

!JavaClassReader methodsFor:'file reading - attributes'!

readAttribute:attributeName for:something

    (attributeName = 'Code') ifTrue:[

        self readCodeAttributeFor:something.

        ^ true.

    ].

    (attributeName = 'LineNumberTable') ifTrue:[

        self readLineNumberTableAttributeFor:something.

        ^ true.

    ].

    (attributeName = 'LocalVariableTable') ifTrue:[

        self readLocalVariableTableAttributeFor:something.

        ^ true.

    ].

    (attributeName = 'ConstantValue') ifTrue:[

        self readConstantValueAttributeFor:something.

        ^ true.

    ].

    (attributeName = 'SourceFile') ifTrue:[

        self readSourceFileAttributeFor:something.

        ^ true.

    ].

    ^ false

    "

     JavaClassReader readFile:'/phys/ibm3/hotjava/classes/browser/AddButton.class'

    "

    "Modified: 15.4.1996 / 15:33:28 / cg"

    "Created: 15.4.1996 / 15:40:17 / cg"

!

readAttributeFor:something

    |attribute_name_index attribute_name attribute_length attribute_info|

    Verbose ifTrue:[Transcript show:'attrib at pos: '; showCR:inStream position].

    attribute_name_index := self nextU2.

    "/

    "/ UNDOC feature ?

    "/

    attribute_name_index > constants size ifTrue:[

        attribute_name_index == 16rb700 ifTrue:[

            self halt.

        ]

    ].

    attribute_name := constants at:attribute_name_index.

    Verbose ifTrue:[Transcript show:'attrib name: '; showCR:attribute_name].

    (self readAttribute:attribute_name for:something) ifFalse:[

        attribute_length := self nextU4.

        attribute_info := ByteArray new:(attribute_length).