- * - * Three classes are produced by this code: - *
- * - * Three parse tables are created as part of the parser class: - *
- * - * In addition to the method interface, this class maintains a series of - * public global variables and flags indicating how misc. parts of the code - * and other output is to be produced, and counting things such as number of - * conflicts detected (see the source code and public variables below for - * more details).
- * - * This class is "static" (contains only static data and methods).
- *
- * @see java_cup.main
- * @version last update: 11/25/95
- * @author Scott Hudson
- */
-
-/* Major externally callable routines here include:
- symbols - emit the symbol constant class
- parser - emit the parser class
-
- In addition the following major internal routines are provided:
- emit_package - emit a package declaration
- emit_action_code - emit the class containing the user's actions
- emit_production_table - emit declaration and init for the production table
- do_action_table - emit declaration and init for the action table
- do_reduce_table - emit declaration and init for the reduce-goto table
-
- Finally, this class uses a number of public instance variables to communicate
- optional parameters and flags used to control how code is generated,
- as well as to report counts of various things (such as number of conflicts
- detected). These include:
-
- prefix - a prefix string used to prefix names that would
- otherwise "pollute" someone else's name space.
- package_name - name of the package emitted code is placed in
- (or null for an unnamed package.
- symbol_const_class_name - name of the class containing symbol constants.
- parser_class_name - name of the class for the resulting parser.
- action_code - user supplied declarations and other code to be
- placed in action class.
- parser_code - user supplied declarations and other code to be
- placed in parser class.
- init_code - user supplied code to be executed as the parser
- is being initialized.
- scan_code - user supplied code to get the next Symbol.
- start_production - the start production for the grammar.
- import_list - list of imports for use with action class.
- num_conflicts - number of conflicts detected.
- nowarn - true if we are not to issue warning messages.
- not_reduced - count of number of productions that never reduce.
- unused_term - count of unused terminal symbols.
- unused_non_term - count of unused non terminal symbols.
- *_time - a series of symbols indicating how long various
- sub-parts of code generation took (used to produce
- optional time reports in main).
-*/
-
-public class emit {
-
- /*-----------------------------------------------------------*/
- /*--- Constructor(s) ----------------------------------------*/
- /*-----------------------------------------------------------*/
-
- /** Only constructor is private so no instances can be created. */
- private emit() { }
-
- /*-----------------------------------------------------------*/
- /*--- Static (Class) Variables ------------------------------*/
- /*-----------------------------------------------------------*/
-
- /** The prefix placed on names that pollute someone else's name space. */
- public static String prefix = "CUP$";
-
- /*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/
-
- /** Package that the resulting code goes into (null is used for unnamed). */
- public static String package_name = null;
-
- /*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/
-
- /** Name of the generated class for symbol constants. */
- public static String symbol_const_class_name = "sym";
-
- /*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/
-
- /** Name of the generated parser class. */
- public static String parser_class_name = "parser";
-
- /*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/
-
- /** User declarations for direct inclusion in user action class. */
- public static String action_code = null;
-
- /*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/
-
- /** User declarations for direct inclusion in parser class. */
- public static String parser_code = null;
-
- /*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/
-
- /** User code for user_init() which is called during parser initialization. */
- public static String init_code = null;
-
- /*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/
-
- /** User code for scan() which is called to get the next Symbol. */
- public static String scan_code = null;
-
- /*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/
-
- /** The start production of the grammar. */
- public static production start_production = null;
-
- /*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/
-
- /** List of imports (Strings containing class names) to go with actions. */
- public static Stack import_list = new Stack();
-
- /*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/
-
- /** Number of conflict found while building tables. */
- public static int num_conflicts = 0;
-
- /*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/
-
- /** Do we skip warnings? */
- public static boolean nowarn = false;
-
- /*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/
-
- /** Count of the number on non-reduced productions found. */
- public static int not_reduced = 0;
-
- /*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/
-
- /** Count of unused terminals. */
- public static int unused_term = 0;
-
- /*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/
-
- /** Count of unused non terminals. */
- public static int unused_non_term = 0;
-
- /*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/
-
- /* Timing values used to produce timing report in main.*/
-
- /** Time to produce symbol constant class. */
- public static long symbols_time = 0;
-
- /** Time to produce parser class. */
- public static long parser_time = 0;
-
- /** Time to produce action code class. */
- public static long action_code_time = 0;
-
- /** Time to produce the production table. */
- public static long production_table_time = 0;
-
- /** Time to produce the action table. */
- public static long action_table_time = 0;
-
- /** Time to produce the reduce-goto table. */
- public static long goto_table_time = 0;
-
- /* frankf 6/18/96 */
- protected static boolean _lr_values;
-
- /** whether or not to emit code for left and right values */
- public static boolean lr_values() {return _lr_values;}
- protected static void set_lr_values(boolean b) { _lr_values = b;}
-
- /*-----------------------------------------------------------*/
- /*--- General Methods ---------------------------------------*/
- /*-----------------------------------------------------------*/
-
- /** Build a string with the standard prefix.
- * @param str string to prefix.
- */
- protected static String pre(String str) {
- return prefix + parser_class_name + "$" + str;
- }
-
- /*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/
-
- /** Emit a package spec if the user wants one.
- * @param out stream to produce output on.
- */
- protected static void emit_package(PrintWriter out)
- {
- /* generate a package spec if we have a name for one */
- if (package_name != null) {
- out.println("package " + package_name + ";"); out.println();
- }
- }
-
- /*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/
-
- /** Emit code for the symbol constant class, optionally including non terms,
- * if they have been requested.
- * @param out stream to produce output on.
- * @param emit_non_terms do we emit constants for non terminals?
- * @param sym_interface should we emit an interface, rather than a class?
- */
- public static void symbols(PrintWriter out,
- boolean emit_non_terms, boolean sym_interface)
- {
- terminal term;
- non_terminal nt;
- String class_or_interface = (sym_interface)?"interface":"class";
-
- long start_time = System.currentTimeMillis();
-
- /* top of file */
- out.println();
- out.println("//----------------------------------------------------");
- out.println("// The following code was generated by " +
- version.title_str);
- out.println("// " + new Date());
- out.println("//----------------------------------------------------");
- out.println();
- emit_package(out);
-
- /* class header */
- out.println("/** CUP generated " + class_or_interface +
- " containing symbol constants. */");
- out.println("public " + class_or_interface + " " +
- symbol_const_class_name + " {");
-
- out.println(" /* terminals */");
-
- /* walk over the terminals */ /* later might sort these */
- for (Enumeration e = terminal.all(); e.hasMoreElements(); )
- {
- term = (terminal)e.nextElement();
-
- /* output a constant decl for the terminal */
- out.println(" public static final int " + term.name() + " = " +
- term.index() + ";");
- }
-
- /* do the non terminals if they want them (parser doesn't need them) */
- if (emit_non_terms)
- {
- out.println();
- out.println(" /* non terminals */");
-
- /* walk over the non terminals */ /* later might sort these */
- for (Enumeration e = non_terminal.all(); e.hasMoreElements(); )
- {
- nt = (non_terminal)e.nextElement();
-
- /* output a constant decl for the terminal */
- out.println(" static final int " + nt.name() + " = " +
- nt.index() + ";");
- }
- }
-
- /* end of class */
- out.println("}");
- out.println();
-
- symbols_time = System.currentTimeMillis() - start_time;
- }
-
- /*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/
-
- /** Emit code for the non-public class holding the actual action code.
- * @param out stream to produce output on.
- * @param start_prod the start production of the grammar.
- */
- protected static void emit_action_code(PrintWriter out, production start_prod)
- throws internal_error
- {
- production prod;
-
- long start_time = System.currentTimeMillis();
-
- /* class header */
- out.println();
- out.println(
- "/** Cup generated class to encapsulate user supplied action code.*/"
- );
- out.println("class " + pre("actions") + " {");
-
- /* user supplied code */
- if (action_code != null)
- {
- out.println();
- out.println(action_code);
- }
-
- /* field for parser object */
- out.println(" private final "+parser_class_name+" parser;");
-
- /* constructor */
- out.println();
- out.println(" /** Constructor */");
- out.println(" " + pre("actions") + "("+parser_class_name+" parser) {");
- out.println(" this.parser = parser;");
- out.println(" }");
-
- /* action method head */
- out.println();
- out.println(" /** Method with the actual generated action code. */");
- out.println(" public final java_cup.runtime.Symbol " +
- pre("do_action") + "(");
- out.println(" int " + pre("act_num,"));
- out.println(" java_cup.runtime.lr_parser " + pre("parser,"));
- out.println(" java.util.Stack " + pre("stack,"));
- out.println(" int " + pre("top)"));
- out.println(" throws java.lang.Exception");
- out.println(" {");
-
- /* declaration of result symbol */
- /* New declaration!! now return Symbol
- 6/13/96 frankf */
- out.println(" /* Symbol object for return from actions */");
- out.println(" java_cup.runtime.Symbol " + pre("result") + ";");
- out.println();
-
- /* switch top */
- out.println(" /* select the action based on the action number */");
- out.println(" switch (" + pre("act_num") + ")");
- out.println(" {");
-
- /* emit action code for each production as a separate case */
- for (Enumeration p = production.all(); p.hasMoreElements(); )
- {
- prod = (production)p.nextElement();
-
- /* case label */
- out.println(" /*. . . . . . . . . . . . . . . . . . . .*/");
- out.println(" case " + prod.index() + ": // " +
- prod.to_simple_string());
-
- /* give them their own block to work in */
- out.println(" {");
-
- /* create the result symbol */
- /*make the variable RESULT which will point to the new Symbol (see below)
- and be changed by action code
- 6/13/96 frankf */
- out.println(" " + prod.lhs().the_symbol().stack_type() +
- " RESULT = null;");
-
- /* Add code to propagate RESULT assignments that occur in
- * action code embedded in a production (ie, non-rightmost
- * action code). 24-Mar-1998 CSA
- */
- for (int i=0; ireduce_goto table. */");
- out.println(" public short[][] reduce_table() {return _reduce_table;}");
- out.println();
-
- goto_table_time = System.currentTimeMillis() - start_time;
- }
-
- // print a string array encoding the given short[][] array.
- protected static void do_table_as_string(PrintWriter out, short[][] sa) {
- out.println("new String[] {");
- out.print(" \"");
- int nchar=0, nbytes=0;
- nbytes+=do_escaped(out, (char)(sa.length>>16));
- nchar =do_newline(out, nchar, nbytes);
- nbytes+=do_escaped(out, (char)(sa.length&0xFFFF));
- nchar =do_newline(out, nchar, nbytes);
- for (int i=0; iEOF Symbol index. */");
- out.println(" public int EOF_sym() {return " + terminal.EOF.index() +
- ";}");
- out.println();
- out.println(" /** error Symbol index. */");
- out.println(" public int error_sym() {return " + terminal.error.index() +
- ";}");
- out.println();
-
- /* user supplied code for user_init() */
- if (init_code != null)
- {
- out.println();
- out.println(" /** User initialization code. */");
- out.println(" public void user_init() throws java.lang.Exception");
- out.println(" {");
- out.println(init_code);
- out.println(" }");
- }
-
- /* user supplied code for scan */
- if (scan_code != null)
- {
- out.println();
- out.println(" /** Scan to get the next Symbol. */");
- out.println(" public java_cup.runtime.Symbol scan()");
- out.println(" throws java.lang.Exception");
- out.println(" {");
- out.println(scan_code);
- out.println(" }");
- }
-
- /* user supplied code */
- if (parser_code != null)
- {
- out.println();
- out.println(parser_code);
- }
-
- /* end of class */
- out.println("}");
-
- /* put out the action code class */
- emit_action_code(out, start_prod);
-
- parser_time = System.currentTimeMillis() - start_time;
- }
-
- /*-----------------------------------------------------------*/
-}