Android Open Source - bad Bad Scope

From Project

Back to project page bad.
License

The source code is released under:
Copyright (C) 2013 Madis Pink Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Softwa...
If you think the Android project bad listed in this page is inappropriate, such as containing malicious code/tools or violating the copyright, please email info at java2s dot com, thanks.
Java Source Code

package com.madisp.bad.eval;
// w w w.  ja v  a  2s .  c om
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.HashMap;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;

import static com.madisp.bad.eval.BadConverter.areAssignableFrom;
import static com.madisp.bad.eval.BadConverter.collapse;
import static com.madisp.bad.eval.BadConverter.isCollapsible;

/**
 * Created with IntelliJ IDEA.
 * User: madis
 * Date: 5/9/13
 * Time: 5:12 PM
 */
public class BadScope implements Scope {
  private Scope parent;
  private Object base;

  private List<OnScopeRebasedListener> watchmen = new LinkedList<OnScopeRebasedListener>();
  private Map<VarKey, BadVar> internalVars = new HashMap<VarKey, BadVar>();

  public BadScope(Scope parent, Object base) {
    this.parent = parent;
    this.base = base;
  }

  @Override
  public void setVar(Object base, String var, Object newValue) {
    if (hasVar(base, var)) {
      setVarImpl(base, var, newValue);
      return;
    }
    Scope scope = walkUp(base, var);
    if (scope != null) {
      scope.setVar(base, var, newValue);
    } else {
      createVarImpl(base, var, newValue);
    }
  }

  @Override
  public Object getVar(Object base, String var) {
    if (hasVar(base, var)) {
      return getVarImpl(base, var);
    }
    Scope scope = walkUp(base, var);
    if (scope != null) {
      return scope.getVar(base, var);
    }
    return createVarImpl(base, var, null);
  }

  @Override
  public boolean hasVar(Object base, String identifier) {
    if ("this".equals(identifier) || "$scope".equals(identifier)) {
      return true;
    }
    return getBadVar(base, identifier) != null || getField(base, identifier) != null;
  }

  @Override
  public Object callMethod(Object base, String name, Object... args) {
    Object mBase = base;
    if (mBase == null) {
      mBase = this.base;
    }
    Method m = getMethodBySignature(mBase, name, args);
    if (m == null && parent != null) {
      return parent.callMethod(base, name, args);
    } else if (m != null) {
      try {
        return m.invoke(mBase, collapse(m.getParameterTypes(), args));
      } catch (IllegalAccessException e) {
        e.printStackTrace();
      } catch (InvocationTargetException e) {
        e.printStackTrace();
      }
    }
    return null;
  }

  @Override
  public Scope getParent() {
    return parent;
  }

  public void setParent(Scope scope) {
    this.parent = scope;
  }

  @Override
  public void rebase(Object newBase) {
    for (OnScopeRebasedListener w : watchmen) {
      w.onScopeDetached(this);
    }
    base = newBase;
    for (OnScopeRebasedListener w : watchmen) {
      w.onScopeAttached(this);
    }
  }

  @Override
  public Object getBase() {
    return base;
  }

  @Override
  public void addOnRebasedListener(OnScopeRebasedListener listener) {
    watchmen.add(listener);
  }

  private Scope walkUp(Object base, String var) {
    Scope scope = this.getParent();
    while (scope != null && !scope.hasVar(base, var)) {
      scope = scope.getParent();
    }
    return scope;
  }

  private void setVarImpl(Object base, String var, Object value) {
    if (base == null) {
      base = this.base;
    }
    BadVar bv = getBadVar(base, var);
    if (bv != null) {
      bv.set(value);
      return;
    }
    Field f = getField(base, var);
    if (f != null) {
      try {
        Object o = f.get(base);
        if (o != null && o instanceof BadVar) {
          ((BadVar)o).set(value);
          return;
        }
        f.set(base, value);
      } catch (IllegalAccessException e) {
        e.printStackTrace();
      }
    }
  }

  private Object getVarImpl(Object base, String var) {
    if (base == null) {
      base = this.base;
    }
    if ("this".equals(var)) {
      return base;
    }
    if ("$scope".equals(var)) {
      return this;
    }
    BadVar bv = getBadVar(base, var);
    if (bv != null) {
      return bv;
    }

    Field f = getField(base, var);
    if (f != null) {
      try {
        return f.get(base);
      } catch (IllegalAccessException e) {
        e.printStackTrace();
      }
    }
    return null;
  }

  private BadVar getBadVar(Object base, String var) {
    if (base == null) {
      base = this.base;
    }
    return internalVars.get(new VarKey(base, var));
  }

  private BadVar createVarImpl(Object base, String var, Object value) {
    if (base == null) {
      base = this.base;
    }
    BadVar bv;
    VarKey key = new VarKey(base, var);
    if ((bv = internalVars.get(key)) == null) {
      bv = new BadVar();
      internalVars.put(key, bv);
    }
    bv.set(value);
    return bv;
  }

  private Method getMethodBySignature(Object base, String name, Object... args) {
    if (base == null) {
      base = this.base;
    }
    Class[] paramClasses = new Class[args.length];
    for (int i = 0; i < paramClasses.length; i++) {
      paramClasses[i] = args[i] == null ? null : args[i].getClass();
    }
    for (Method m : base.getClass().getMethods()) {
      if (m.getName().equals(name)) {
        Class<?>[] paramTypes = m.getParameterTypes();
        if (isCollapsible(paramTypes, paramClasses)) {
          return m;
        } else if (areAssignableFrom(paramTypes, paramClasses)) {
          // signature matches
          return m;
        }
      }
    }
    return null;
  }

  private Field getField(Object base, String identifier) {
    if (base == null) {
      base = this.base;
    }
    if (base == null) {
      return null;
    }
    for (Field f : base.getClass().getDeclaredFields()) {
      if (f.getName().equals(identifier)) {
        return f;
      }
    }
    return null;
  }

  private static class VarKey {
    Object base;
    String identifier;

    private VarKey(Object base, String identifier) {
      this.base = base;
      this.identifier = identifier;
    }

    @Override
    public boolean equals(Object o) {
      if (this == o) return true;
      if (o == null || getClass() != o.getClass()) return false;

      VarKey varKey = (VarKey) o;

      if (base != null ? base.hashCode() != varKey.base.hashCode() : varKey.base != null) return false;
      if (!identifier.equals(varKey.identifier)) return false;

      return true;
    }

    @Override
    public int hashCode() {
      int result = base != null ? base.hashCode() : 0;
      result = 31 * result + identifier.hashCode();
      return result;
    }
  }
}
Java Source Code List
