GenericCompiler (BandM metatools API doc)

java.lang.Object
- eu.bandm.tools.tdom.runtime.BaseVisitor
- - eu.bandm.tools.formatfrontends.absy.Visitor
  - - eu.bandm.tools.formatfrontends.GenericCompiler

All Implemented Interfaces:

PCDataVisitor

Direct Known Subclasses:

Tdom2format, UMod2format.Compiler
```
public abstract class GenericCompiler
extends eu.bandm.tools.formatfrontends.absy.Visitor
```
Base class for different compilers which generate format-generating java sources, realizing the code generation for the common constructs of the format description language.

A specialization of this class generates code for generating formats by acting as a visitor of the format language tdom model, and creating code which (in most cases) is also a visitor, of some target model.

Any derived visitor has to act as follows:
1. It has to construct some target class (with the appropriate base class, specific fields, interface methods, etc)
2. It has to call initTransformerClass(GeneratedClass) on this class.
3. It has to define the visit() methods for all the specific language constructs.
4. It has to call compileOnePattern(Element_pattern) for each expression it wants to translate. This method intializes internal registers, calls visit(), and finally relocates all constant expressions to initializer blocks.
  The format result (which contains code to construct the required format) is left in fresult, The caller has to store this code in the generated class according to its need.
5. During the execution of the specific code, the following registers are relevant:
  - fresult (read/write) holding the code = translation result. ("f-result" = "functional result"),
  - isdynamic (read/write) must be set by custom code to true in most cases, ie. when the constructed format will not be constant, but will depend on the data.
  - checkedmode (read) if we are at the left of some "?" operator,
6. Whenever a sub-structure of aggreate type has to be compiled, a sub-class of GenericCompiler.Subformat can be defined. This class reduces all relevant parameters from the font-end constructs for aggregates (fold operators, code, etc.) into interal values and stores them, for easy recursion.

Nested Class Summary

Nested Classes
Modifier and Type	Class and Description
`protected class`	`GenericCompiler.Subformat` A sub-parser which extracts the list format description for a sub-object which is an aggregate, and stores them locally, for ease of recursion.

Field Summary

Fields
Modifier and Type	Field and Description
`Format`	`callFunctionForRaisingException` format for calling the method which throws `TakeAlternativeException`, cf `NAME_METHOD_THROW_TAKE_ALTERNATIVE`.
`protected boolean`	`checkedmode` are we currently visiting left part of a "?" operator ?
`protected Map<String,Format>`	`constcache` Maps "fresult" contents (=unformatted java code, used as a key) to the name of the constant fields which will hold the code's result.
`protected Map<String,Format>`	`exprCache`
`protected Format`	`fresult` accumulator for format generating functional code.
`protected boolean`	`isdynamic` indicates whether the code currently contained in `fresult` does generate formats "dynamically" (which implies that its result can NOT be stored in a constant field).
`protected static int`	`MODIF_CONST` modifier used for all fields generated to hold constant format expressions (= "protected static final").
`protected SimpleMessage.Generator<XMLDocumentIdentifier>`	`msg`
`protected String`	`NAME_CONST_FORMAT_EMPTY` name of the generated field which holds an empty format, normally "`format_empty`".
`String`	`NAME_METHOD_THROW_TAKE_ALTERNATIVE` name of the method generated for convenience for throwing `TakeAlternativeException`.
`protected String`	`NAME_VAR_DEFAULT_INDENT` name of the generated field which holds the default idententation, normally "`default_indent`".
`protected String`	`NAME_VAR_FORMAT_RESULT` name of the generated field which holds the resulting format.
`protected String`	`NAME_VAR_MODE` name of the generated field which holds the current mode, normally "`mode`".
`protected MessageReceiver<SimpleMessage<XMLDocumentIdentifier>>`	`rec` Needed ONLY because ".getReceiver()" is of type "? super M", which does not wokr.
`static Format`	`REF_FORMAT_Format` The format which refers to `Format`
`protected GeneratedClass`	`targetclass` class into which to generate all const field definitions.
`static EnvironmentClass`	`WRAPPEDCLASS_CompoundConstructor`
`static EnvironmentClass`	`WRAPPEDCLASS_Format`
`static EnvironmentClass`	`WRAPPEDCLASS_Function` Refers to `eu.bandm.tools.ops`, and is for convenience of derived compilers only.
`static EnvironmentClass`	`WRAPPEDCLASS_ListoidFormatter` For convenience of derived compilers only.
`static EnvironmentClass`	`WRAPPEDCLASS_Lists` Attention, refers NOT to java.util, but to `eu.bandm.tools.ops`, and is for convenience of derived compilers only.
`static EnvironmentClass`	`WRAPPEDCLASS_MapEntry` For convenience of derived compilers only.
`static EnvironmentClass`	`WRAPPEDCLASS_MapoidFormatter` For convenience of derived compilers only.
`static EnvironmentClass`	`WRAPPEDCLASS_Object`
`static EnvironmentClass`	`WRAPPEDCLASS_TakeAlternativeException`
`static EnvironmentClass`	`WRAPPEDCLASS_TryerCatcher`

Fields inherited from class eu.bandm.tools.tdom.runtime.BaseVisitor
validating

Constructor Summary

Constructors
Constructor and Description

GenericCompiler(MessageReceiver<SimpleMessage<XMLDocumentIdentifier>> rec)

Constructors
Constructor and Description
`GenericCompiler(MessageReceiver<SimpleMessage<XMLDocumentIdentifier>> rec)`

Method Summary

All Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method and Description
`protected void`	`checkconst()` Whenever possible, store the code from `fresult` into an initializer of a new constant, and replace `fresult` by a reference to this (or to an already existing constant).
`protected void`	`compileCallToFormatText(Format model)` compiles a call to `Format.text(String)`, if model != null.
`protected void`	`compileModeSwitch(eu.bandm.tools.formatfrontends.absy.Element_cases el)` Compiles a switch statement with `$mode` as its selector.
`void`	`compileOnePattern(eu.bandm.tools.formatfrontends.absy.Element_pattern el)` called from derived code for translating one(1) rule.
`void`	`create_resultfield(GeneratedClass gc)` creates a field "`Format result=Format.empty;`" for formatting wisitors which need such a temp storage (ie.
`protected Format`	`expr(String code)`
`protected abstract Format`	`getCurrentModel()` Currently only needed to compile `escapeToJava()` in the variant operating directly on the model element.
`protected MessageReceiver<SimpleMessage<XMLDocumentIdentifier>>`	`getMsgReceiver()`
`void`	`initTransformerClass(GeneratedClass gc)` Creates standard fields for the generated format generating class.
`protected void`	`process_compound(eu.bandm.tools.formatfrontends.absy.Element[] subs, String constr)`
`protected Format`	`refer(CompoundConstructor c)`
`protected void`	`setMsgReceiver(MessageReceiver<SimpleMessage<XMLDocumentIdentifier>> rec)`
`void`	`visit(eu.bandm.tools.formatfrontends.absy.Element_alternative element)` Compiles the cascade of alternatives/catch clauses from the front end representation {@code ...? ...
`void`	`visit(eu.bandm.tools.formatfrontends.absy.Element_append element)`
`void`	`visit(eu.bandm.tools.formatfrontends.absy.Element_beneath element)`
`void`	`visit(eu.bandm.tools.formatfrontends.absy.Element_beside element)`
`void`	`visit(eu.bandm.tools.formatfrontends.absy.Element_block element)`
`void`	`visit(eu.bandm.tools.formatfrontends.absy.Element_escapeToJava element)` Creates code for a java escape.
`void`	`visit(eu.bandm.tools.formatfrontends.absy.Element_indent element)` creates code for indentation.
`void`	`visit(eu.bandm.tools.formatfrontends.absy.Element_line element)`
`void`	`visit(eu.bandm.tools.formatfrontends.absy.Element_literal el)` Creates code for one literal, which might also be empty.
`void`	`visit(eu.bandm.tools.formatfrontends.absy.Element_nullException el)` Creates code for the `$throw` element.
`void`	`visit(eu.bandm.tools.formatfrontends.absy.Element_prior el)` `<!ELEMENT prior (number, (number \| appendOp)?, pattern, pattern) >` It directly maps its arguments to a call of `Format.prior(int, int, eu.bandm.tools.format.Format, eu.bandm.tools.format.Format)`.
`void`	`visit(eu.bandm.tools.formatfrontends.absy.Element_tabular element)`
`void`	`visit(eu.bandm.tools.formatfrontends.absy.Element_whitespace el)` Creates code for whitespace.

Methods inherited from class eu.bandm.tools.formatfrontends.absy.Visitor
visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit, visit

Methods inherited from class eu.bandm.tools.tdom.runtime.BaseVisitor
visit

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - WRAPPEDCLASS_Object
```
public static final EnvironmentClass WRAPPEDCLASS_Object
```
  - WRAPPEDCLASS_Lists
```
public static final EnvironmentClass WRAPPEDCLASS_Lists
```
    Attention, refers NOT to java.util, but to eu.bandm.tools.ops, and is for convenience of derived compilers only.
  - WRAPPEDCLASS_Function
```
public static final EnvironmentClass WRAPPEDCLASS_Function
```
    Refers to eu.bandm.tools.ops, and is for convenience of derived compilers only.
  - WRAPPEDCLASS_Format
```
public static final EnvironmentClass WRAPPEDCLASS_Format
```
  - REF_FORMAT_Format
```
public static final Format REF_FORMAT_Format
```
    The format which refers to Format
  - WRAPPEDCLASS_TakeAlternativeException
```
public static final EnvironmentClass WRAPPEDCLASS_TakeAlternativeException
```
  - WRAPPEDCLASS_MapoidFormatter
```
public static final EnvironmentClass WRAPPEDCLASS_MapoidFormatter
```
    For convenience of derived compilers only.
  - WRAPPEDCLASS_MapEntry
```
public static final EnvironmentClass WRAPPEDCLASS_MapEntry
```
    For convenience of derived compilers only.
  - WRAPPEDCLASS_ListoidFormatter
```
public static final EnvironmentClass WRAPPEDCLASS_ListoidFormatter
```
    For convenience of derived compilers only.
  - WRAPPEDCLASS_TryerCatcher
```
public static final EnvironmentClass WRAPPEDCLASS_TryerCatcher
```
  - WRAPPEDCLASS_CompoundConstructor
```
public static final EnvironmentClass WRAPPEDCLASS_CompoundConstructor
```
  - NAME_METHOD_THROW_TAKE_ALTERNATIVE
```
public final String NAME_METHOD_THROW_TAKE_ALTERNATIVE
```
    name of the method generated for convenience for throwing TakeAlternativeException.
    
    See Also:
    
    Constant Field Values
  - callFunctionForRaisingException
```
public final Format callFunctionForRaisingException
```
    format for calling the method which throws TakeAlternativeException, cf NAME_METHOD_THROW_TAKE_ALTERNATIVE.
  - NAME_VAR_DEFAULT_INDENT
```
protected String NAME_VAR_DEFAULT_INDENT
```
    name of the generated field which holds the default idententation, normally "default_indent".
  - NAME_VAR_MODE
```
protected String NAME_VAR_MODE
```
    name of the generated field which holds the current mode, normally "mode".
  - NAME_CONST_FORMAT_EMPTY
```
protected String NAME_CONST_FORMAT_EMPTY
```
    name of the generated field which holds an empty format, normally "format_empty".
  - MODIF_CONST
```
protected static final int MODIF_CONST
```
    modifier used for all fields generated to hold constant format expressions (= "protected static final").
    
    See Also:
    
    Constant Field Values
  - NAME_VAR_FORMAT_RESULT
```
protected String NAME_VAR_FORMAT_RESULT
```
    name of the generated field which holds the resulting format. such a field is NOT necesarry and not created iff the generated code (including facade code !) can be fully functional.
  - exprCache
```
protected Map<String,Format> exprCache
```
  - rec
```
protected MessageReceiver<SimpleMessage<XMLDocumentIdentifier>> rec
```
    Needed ONLY because ".getReceiver()" is of type "? super M", which does not wokr.
  - msg
```
protected final SimpleMessage.Generator<XMLDocumentIdentifier> msg
```
  - targetclass
```
protected GeneratedClass targetclass
```
    class into which to generate all const field definitions.
  - isdynamic
```
protected boolean isdynamic
```
    indicates whether the code currently contained in fresult does generate formats "dynamically" (which implies that its result can NOT be stored in a constant field).
  - checkedmode
```
protected boolean checkedmode
```
    are we currently visiting left part of a "?" operator ?
  - fresult
```
protected Format fresult
```
    accumulator for format generating functional code. (of course coded in form of a format !-).
  - constcache
```
protected final Map<String,Format> constcache
```
    Maps "fresult" contents (=unformatted java code, used as a key) to the name of the constant fields which will hold the code's result.
- Constructor Detail
  - GenericCompiler
```
public GenericCompiler(MessageReceiver<SimpleMessage<XMLDocumentIdentifier>> rec)
```
- Method Detail
  - setMsgReceiver
```
protected void setMsgReceiver(MessageReceiver<SimpleMessage<XMLDocumentIdentifier>> rec)
```
  - getMsgReceiver
```
protected MessageReceiver<SimpleMessage<XMLDocumentIdentifier>> getMsgReceiver()
```
  - getCurrentModel
```
protected abstract Format getCurrentModel()
```
    Currently only needed to compile escapeToJava() in the variant operating directly on the model element. Introduced 20170428.
  - refer
```
protected Format refer(CompoundConstructor c)
```
  - expr
```
protected Format expr(String code)
```
  - initTransformerClass
```
public void initTransformerClass(GeneratedClass gc)
```
    Creates standard fields for the generated format generating class. (Like "default indent", "result" as intermediate storage, a cache of the empty format, a method to throw the "take alternative" exception, etc.) Must be called. This is ensured by the field targetclass, which otherwise stays =null.
  - create_resultfield
```
public void create_resultfield(GeneratedClass gc)
```
    creates a field "Format result=Format.empty;" for formatting wisitors which need such a temp storage (ie. are not purely functinal code).
    Currently used by UMod2format and Tdom2format.
  - compileOnePattern
```
public void compileOnePattern(eu.bandm.tools.formatfrontends.absy.Element_pattern el)
```
    called from derived code for translating one(1) rule. (1) initialize registers, (2) call visit(el) and (3) leave result in fresult. after return, the contents of fresult (=format representing format-generating code) must be stored to somewhere by the calling code!
  - checkconst
```
protected void checkconst()
```
    Whenever possible, store the code from fresult into an initializer of a new constant, and replace fresult by a reference to this (or to an already existing constant).
  - process_compound
```
protected void process_compound(eu.bandm.tools.formatfrontends.absy.Element[] subs,
                                String constr)
```
  - visit
```
public void visit(eu.bandm.tools.formatfrontends.absy.Element_beneath element)
```
    Overrides:
    
    visit in class eu.bandm.tools.formatfrontends.absy.Visitor
  - visit
```
public void visit(eu.bandm.tools.formatfrontends.absy.Element_beside element)
```
    Overrides:
    
    visit in class eu.bandm.tools.formatfrontends.absy.Visitor
  - visit
```
public void visit(eu.bandm.tools.formatfrontends.absy.Element_line element)
```
    Overrides:
    
    visit in class eu.bandm.tools.formatfrontends.absy.Visitor
  - visit
```
public void visit(eu.bandm.tools.formatfrontends.absy.Element_block element)
```
    Overrides:
    
    visit in class eu.bandm.tools.formatfrontends.absy.Visitor
  - visit
```
public void visit(eu.bandm.tools.formatfrontends.absy.Element_append element)
```
    Overrides:
    
    visit in class eu.bandm.tools.formatfrontends.absy.Visitor
  - visit
```
public void visit(eu.bandm.tools.formatfrontends.absy.Element_tabular element)
```
    Overrides:
    
    visit in class eu.bandm.tools.formatfrontends.absy.Visitor
  - compileModeSwitch
```
protected void compileModeSwitch(eu.bandm.tools.formatfrontends.absy.Element_cases el)
```
    Compiles a switch statement with $mode as its selector. Defaults to the empty format.
  - compileCallToFormatText
```
protected void compileCallToFormatText(Format model)
```
    compiles a call to Format.text(String), if model != null. otherwise an exception or an empty format, if not left of a "?".
  - visit
```
public void visit(eu.bandm.tools.formatfrontends.absy.Element_alternative element)
```
    Compiles the cascade of alternatives/catch clauses from the front end representation ...? ... ? ... ? ... .
    
    Overrides:
    
    visit in class eu.bandm.tools.formatfrontends.absy.Visitor
  - visit
```
public void visit(eu.bandm.tools.formatfrontends.absy.Element_nullException el)
```
    Creates code for the $throw element. This causes explicit failure, i.e. throwing of an instance of TakeAlternativeException. This is sensible when eg. done out of one (or some) of the cases of a $switch statement. It may only be used to the left side of a ? operator, which results in the corresponding right side to be executed.
    
    Overrides:
    
    visit in class eu.bandm.tools.formatfrontends.absy.Visitor
  - visit
```
public void visit(eu.bandm.tools.formatfrontends.absy.Element_prior el)
```
    <!ELEMENT prior (number, (number | appendOp)?, pattern, pattern) > It directly maps its arguments to a call of Format.prior(int, int, eu.bandm.tools.format.Format, eu.bandm.tools.format.Format).
    
    Overrides:
    
    visit in class eu.bandm.tools.formatfrontends.absy.Visitor
  - visit
```
public void visit(eu.bandm.tools.formatfrontends.absy.Element_literal el)
```
    Creates code for one literal, which might also be empty. Consequently, is compiles to Format.literal(String) or to Format.empty
    
    Overrides:
    
    visit in class eu.bandm.tools.formatfrontends.absy.Visitor
  - visit
```
public void visit(eu.bandm.tools.formatfrontends.absy.Element_whitespace el)
```
    Creates code for whitespace. The width of the input is preserved in the generated format. Creates a call to Format.space(int)
    
    Overrides:
    
    visit in class eu.bandm.tools.formatfrontends.absy.Visitor
  - visit
```
public void visit(eu.bandm.tools.formatfrontends.absy.Element_escapeToJava element)
```
    Creates code for a java escape.
    The syntax in the front end language is "$java 'my.package.Class.method'(formatsAsArgument..)". or "$java 'my.package.Class.method'". The first argument must point to some static function from Format to Format. If there is a second argument, it is a "block" construct of formats which are arguments to the function. Otherwise the current model element is the only argument.
    Attention: "$java" is now one level higher than "atom"; can be used as an instance of "atom" simply by additional parentheses "($java x.y(..))"
    
    Overrides:
    
    visit in class eu.bandm.tools.formatfrontends.absy.Visitor
  - visit
```
public void visit(eu.bandm.tools.formatfrontends.absy.Element_indent element)
```
    creates code for indentation.
    Supports two variants: with inline constant, or without, reading a runtime variable for default indentation. The name of this variable is defined by NAME_VAR_DEFAULT_INDENT
    
    Overrides:
    
    visit in class eu.bandm.tools.formatfrontends.absy.Visitor

Class GenericCompiler

Nested Class Summary

Field Summary

Fields inherited from class eu.bandm.tools.tdom.runtime.BaseVisitor

Constructor Summary

Method Summary

Methods inherited from class eu.bandm.tools.formatfrontends.absy.Visitor

Methods inherited from class eu.bandm.tools.tdom.runtime.BaseVisitor

Methods inherited from class java.lang.Object

Field Detail

WRAPPEDCLASS_Object

WRAPPEDCLASS_Lists

WRAPPEDCLASS_Function

WRAPPEDCLASS_Format

REF_FORMAT_Format

WRAPPEDCLASS_TakeAlternativeException

WRAPPEDCLASS_MapoidFormatter

WRAPPEDCLASS_MapEntry

WRAPPEDCLASS_ListoidFormatter

WRAPPEDCLASS_TryerCatcher

WRAPPEDCLASS_CompoundConstructor

NAME_METHOD_THROW_TAKE_ALTERNATIVE

callFunctionForRaisingException

NAME_VAR_DEFAULT_INDENT

NAME_VAR_MODE

NAME_CONST_FORMAT_EMPTY

MODIF_CONST

NAME_VAR_FORMAT_RESULT

exprCache

rec

msg

targetclass

isdynamic

checkedmode

fresult

constcache

Constructor Detail

GenericCompiler

Method Detail

setMsgReceiver

getMsgReceiver

getCurrentModel

refer

expr

initTransformerClass

create_resultfield

compileOnePattern

checkconst

process_compound

visit

visit

visit

visit

visit

visit

compileModeSwitch

compileCallToFormatText

visit

visit

visit

visit

visit

visit

visit