Object subclass:#JavaClassReader

	instanceVariableNames:'inStream msb constants majorVsn minorVsn constNeeds2Slots

		constSlot'

	poolDictionaries:''

	category:'Java-Support'

!

initialize

    Verbose := false. 

    Silent := true.

    AbsolutelySilent := false.

    LazyClassLoading := false. "/ true.

    "

     JavaClassReader initialize

    "

! !

verbose:aBoolean

    Verbose := aBoolean

    "

     Java flushClasses.

     JavaClassReader verbose:true

     JavaClassReader verbose:false

    "

! !

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.

    rslt notNil ifTrue:[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 cls loadedClass|

    (aClassName endsWith:';') ifTrue:[

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

        self halt:'should not happen'.

        ^ nil

    ].

    (aClassName endsWith:'[]') ifTrue:[

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

        self halt:'should not happen'.

        ^ nil

    ].

    clsName := aClassName.

    (clsName includes:$.) ifTrue:[

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

    ].

    (classesBeingLoaded notNil and:[classesBeingLoaded includes:clsName]) ifTrue:[

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

        self halt:'should not happen'.

        ^ JavaUnresolvedClassConstant fullName:clsName

    ].

    (cls := Java at:clsName) notNil ifTrue:[

        ('oops - ' , clsName , ' is already loaded') printNL.

        self halt:'should not happen'.

        ^ cls

    ].

    classesBeingLoaded isNil ifTrue:[

        loadedClass := Set with:clsName

    ] ifFalse:[

        loadedClass := Set withAll:classesBeingLoaded.

        loadedClass add:clsName.

    ].

        ]

    ].

    ('JAVA: no file found for: ' , clsName) infoPrintCR.

    ^ nil

!

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.

     Strings are fixed and classrefs are fixed, 

     but NO no class-init functions are called."

    |javaClass pool|

    javaClass := self readFile:aFilename ignoring:classesBeingLoaded.

    javaClass notNil ifTrue:[

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

        classesBeingLoaded remove:javaClass fullName ifAbsent:nil.

        JavaUnresolvedConstant resolveFor:javaClass.

    ].

    ^ 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)."

    |classes prevUnresolved newUnresolved|

    "/ need at least java.lang.String, for valid constants

    Java javaString isNil ifTrue:[

        self loadClassLazy:'java.lang.String' ignoring:Set new.

    ].

    LazyClassLoading ifFalse:[

        prevUnresolved := nil.

        newUnresolved := JavaUnresolvedConstant unresolvedClassNames asArray.

        [prevUnresolved ~= newUnresolved] whileTrue:[

            newUnresolved do:[:nextUnresolved |

                (Java at:nextUnresolved) isNil ifTrue:[ "/ could have been loaded in the meantime

                    Silent ifFalse:[

                        'loading unresolved: ' print. nextUnresolved printCR.

                    ].

                    self

                        loadClassLazy:nextUnresolved

                        ignoring:Set new.

                ]

            ].

            prevUnresolved := newUnresolved.

            newUnresolved := JavaUnresolvedConstant unresolvedClassNames asArray.

        ].

        newUnresolved size == 0 ifTrue:[

            "/ nothing unresolved

            (classes := Java allClasses) notNil ifTrue:[

                "/ init all new classes

                "/ fetch again - there could be new ones ...

                classes := Java allClasses.

                classes do:[:aJavaClass |

                    aJavaClass isInitialized ifFalse:[

                        Silent ifFalse:[

                            'performing class initialization of ' print. aJavaClass fullName printCR.

                        ].

                        aJavaClass classInit

                    ]

                ]

            ]

        ].

    ]

!

readFile:aFilename ignoring:classesBeingLoaded

    "reads a class from aFilename and returns it.

     The JavaClass is NOT installed as global and unresolved

     refs are NOT patched."

    |inStream javaClass|

    Silent ifFalse:[

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

    ].

    inStream := aFilename asFilename readStream.

    inStream isNil ifTrue:[

        ('no file: ' , aFilename) printCR.

        self halt.

        ^ nil

    ].

    javaClass := self new readStream:inStream ignoring:classesBeingLoaded.

    javaClass notNil ifTrue:[

        javaClass setBinaryFilePath:(inStream pathName).

    ].

    inStream close.

    AbsolutelySilent ifFalse:[

        '  ... loaded ' print. javaClass displayString printNL.

    ].

    ^ javaClass

    "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 := inStream nextUnsignedLongMSB:msb.

    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

    "/

    minorVsn := inStream nextUnsignedShortMSB:msb.

    majorVsn := inStream nextUnsignedShortMSB:msb.

    (majorVsn ~~ 45 or:[minorVsn ~~ 3]) ifTrue:[

        Transcript show:'warning this file has version '; show:majorVsn; show:'.'; showCR:minorVsn. 

    ].

    Verbose ifTrue:[

        Transcript show:'version = '; 

                   show:(majorVsn printString); 

                   show:'.';

                   showCR:(minorVsn printString).

    ].

    "/

    "/ get constant pool

    "/

    self readConstantPool.

    "/

    "/ access flags

    "/

    access_flags := inStream nextUnsignedShortMSB:msb.

    this_class_index := inStream nextUnsignedShortMSB:msb.

    super_class_index := inStream nextUnsignedShortMSB:msb.

    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:[

                Silent ifFalse:[

                    'load superClass: ' print. super_class fullName printCR.

                ].

                existingSuperClass := self class 

                                    loadClassLazy:(super_class fullName)

                                    ignoring:classesbeingLoaded.

                existingSuperClass isNil ifTrue:[

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

                ].

                super_class := existingSuperClass

            ] ifFalse:[

                self halt:'oops - superclass ?'

            ]

        ].

    ].

    "/

    "/ 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) numStatic:0.

    ].

    this_class setAccessFlags:access_flags.

    this_class setSuperclass:super_class.

    this_class setConstantPool:constants.

    this_class setFields:fields.

    this_class setInterfaces:interfaces.

    "/

    "/ get methods

    "/

    self readMethodsFor:this_class.

    self readAttributesFor:this_class.

    constants owner: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 := inStream nextUnsignedLongMSB:msb.

    sourceFile_index := inStream nextUnsignedShortMSB:msb.

    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'