Initial constant_pool[] Entries

There are several entries in the constant_pool[] that have to be present in every class file. These entries are:

• a CONSTANT_Class_info describing the superclass, in our case the class java.lang.Object;
• a CONSTANT_Class_info describing this class, in case of a Pascal program that is the name of the program. This way a Pascal program becomes one Java class;
• a CONSTANT_Methodref_info entry describing the instance initialization method <init> of the class java.lang.Object, the superclass of this method.

Other entries needed by the above entries, like the CONSTANT_Utf8_info entries containing the names and CONSTANT_NameAndType_info entry needed by the CONSTANT_Methodref_info entry describing <init>, and entries containing the name and descriptor of the main method are of course also present.

Something I did not expect was that javac also put the CONSTANT_Utf8_info entries in the constant_pool[] containing the names of the attributes ( Code, Exceptions, LineNumberTable, LocalVariableTable, SourceFile and ConstantValue), even if they are not used. This of course does not mean they have to be put in there.