Java example source code file (RuleGroup.java)

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Java - Java tags/keywords

checking, classcase, defender, hashset, marker, p\-ideclare, provenence, r\-resolve, resolution, rule, rulegroup, runtimeexception, set, string, util

The RuleGroup.java Java example source code

/*
 * Copyright (c) 2012, 2013, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

package shapegen;

import java.util.HashSet;
import java.util.Set;

import static shapegen.ClassCase.Kind.*;

/**
 *
 * @author Robert Field
 */
public class RuleGroup {

    final String name;
    private final Rule[] rules;

    public RuleGroup(String name, Rule[] rules) {
        this.name = name;
        this.rules = rules;
    }

    public boolean exec(ClassCase cc) {
        boolean found = false;
        for (Rule rule : rules) {
            if (rule.guard(cc)) {
                if (found) {
                    throw new RuntimeException("Bad rules -- multiple matches " + toString() + " for " + cc);
                } else {
                    rule.eval(cc);
                    found = true;
                }
            }
        }
        return found;
    }

    @Override
    public String toString() {
        return name;
    }

    public static RuleGroup PROVENENCE = new RuleGroup("Provenence", new Rule[] {
      new Rule("P-CDeclare") {
          boolean guard(ClassCase cc) {
              return cc.isa(CCONCRETE, CABSTRACT);
          }

          void eval(ClassCase cc) {
              cc.set_mprov(cc);
              cc.set_HasClassMethod(true);
          }
      },

      new Rule("P-IDeclare") {
          boolean guard(ClassCase cc) {
              return cc.isa(IDEFAULT, IPRESENT);
          }

          void eval(ClassCase cc) {
              cc.set_mprov(cc);
          }
      },

      new Rule("P-IntfInh") {
          boolean guard(ClassCase cc) {
              return cc.isa(IVAC, CNONE) && !(cc.hasSuperclass() && cc.getSuperclass().get_HasClassMethod());
          }

          void eval(ClassCase cc) {
              Set<ClassCase> _S = new HashSet<>();
              for (ClassCase t : cc.getSupertypes()) {
                  _S.addAll(t.get_mprov());
              }
              Set<ClassCase> tops = new HashSet<>();
              for (ClassCase _W : _S) {
                  for (ClassCase _V : _S) {
                      if (_V.equals(_W) || !(_V.isSubtypeOf(_W))) {
                          tops.add(_W);
                      }
                  }
              }
              cc.set_mprov(tops);
          }
      },

      new Rule("P-ClassInh") {
          boolean guard(ClassCase cc) {
              return cc.isa(CNONE) && (cc.hasSuperclass() && cc.getSuperclass().get_HasClassMethod());
          }

          void eval(ClassCase cc) {
              cc.set_mprov(cc.getSuperclass());
              cc.set_HasClassMethod(true);
          }
      },

    });

    public static RuleGroup MARKER = new RuleGroup("Marker", new Rule[] {
      new Rule("M-Default") {
          boolean guard(ClassCase cc) {
              return cc.isa(IDEFAULT);
          }

          void eval(ClassCase cc) {
              cc.set_HasDefault(true);
          }
      },

      new Rule("M-Conc") {
          boolean guard(ClassCase cc) {
            return cc.isa(CCONCRETE);
          }

          void eval(ClassCase cc) {
              cc.set_IsConcrete(true);
          }
      },

    });

    public static RuleGroup RESOLUTION = new RuleGroup("Resolution", new Rule[] {
      new Rule("R-Resolve") {
          boolean guard(ClassCase cc) {
              if (!(cc.isClass() && cc.get_mprov().size() == 1)) {
                  return false;
              }
              ClassCase _V = cc.get_mprov().iterator().next();
              return _V.get_IsConcrete() || _V.get_HasDefault();
          }

          void eval(ClassCase cc) {
              ClassCase _V = cc.get_mprov().iterator().next();
              cc.set_mres(_V);
          }
      },

    });

    public static RuleGroup DEFENDER = new RuleGroup("Defender", new Rule[] {
      new Rule("D-Defend") {
          boolean guard(ClassCase cc) {
              ClassCase mresSuper = cc.hasSuperclass() ? cc.getSuperclass().get_mres() : null;
              boolean eq = cc.get_mres() == null ? mresSuper == null : cc.get_mres().equals(mresSuper);
              return cc.isa(CNONE) && !eq;
          }

          void eval(ClassCase cc) {
              cc.set_mdefend(cc.get_mres());
          }
      },

    });

    public static RuleGroup CHECKING = new RuleGroup("Checking", new Rule[] {
      new Rule("C-Check") {
          boolean guard(ClassCase cc) {
              for (ClassCase t : cc.getSupertypes()) {
                  if (! t.get_OK()) {
                      return false;
                  }
              }
              int defenderCount = 0;
              int provCount = 0;
              for (ClassCase prov : cc.get_mprov()) {
                  if (prov.get_HasDefault()) {
                      defenderCount++;
                  }
                  provCount++;
              }
              return provCount <= 1 || defenderCount == 0;
          }

          void eval(ClassCase cc) {
              cc.set_OK(true);
          }
      },

    });

}