/*
* 01/11/2010
*
* Copyright (C) 2011 Robert Futrell
* robert_futrell at users.sourceforge.net
* http://fifesoft.com/rsyntaxtextarea
*
* This library is distributed under a modified BSD license. See the included
* RSTALanguageSupport.License.txt file for details.
*/
package org.fife.rsta.ac.common;
import java.util.ArrayList;
import java.util.List;
/**
* A block of code. This can be used to implement <em>very</em> simple
* parsing for languages that have some concept of code blocks, such as C,
* Perl, Java, etc. Currently, using <code>CodeBlock</code>s provides a
* means of remembering where variables are defined, as well as their scopes.
*
* @author Robert Futrell
* @version 1.0
* @see VariableDeclaration
*/
public class CodeBlock {
private int start;
private int end;
private CodeBlock parent;
private List children;
private List varDecs;
/**
* Constructor.
*
* @param start The starting offset of the code block.
*/
public CodeBlock(int start) {
this.start = start;
end = Integer.MAX_VALUE;
}
/**
* Creates and returns a child (nested) code block.
*
* @param start The starting offset of the nested code block.
* @return The code block.
*/
public CodeBlock addChildCodeBlock(int start) {
CodeBlock child = new CodeBlock(start);
child.parent = this;
if (children==null) {
children = new ArrayList();
}
children.add(child);
return child;
}
/**
* Adds a variable declaration.
*
* @param varDec The variable declaration.
*/
public void addVariable(VariableDeclaration varDec) {
if (varDecs==null) {
varDecs = new ArrayList();
}
varDecs.add(varDec);
}
/**
* Returns whether this code block contains a given offset.
*
* @param offset The offset.
* @return Whether this code block contains that offset.
*/
public boolean contains(int offset) {
return offset>=start && offset<end;
}
/**
* Returns a child code block.
*
* @param index The index of the child code block.
* @return The child code block.
* @see #getChildCodeBlockCount()
*/
public CodeBlock getChildCodeBlock(int index) {
return (CodeBlock)children.get(index);
}
/**
* Returns the number of child code blocks.
*
* @return The child code block count.
* @see #getChildCodeBlock(int)
*/
public int getChildCodeBlockCount() {
return children==null ? 0 : children.size();
}
/**
* Returns the deepest code block nested under this one (or this one
* itself) containing a given offset.
*
* @param offs The offset to look for.
* @return The deepest-nested code block containing the offset, or
* <code>null</code> if this code block and none of its children
* contain the offset.
*/
public CodeBlock getDeepestCodeBlockContaining(int offs) {
if (!contains(offs)) {
return null;
}
for (int i=0; i<getChildCodeBlockCount(); i++) {
CodeBlock child = getChildCodeBlock(i);
if (child.contains(offs)) {
return child.getDeepestCodeBlockContaining(offs);
}
}
return this;
}
/**
* Returns the end offset of this code block.
*
* @return The end offset.
* @see #getStartOffset()
* @see #setEndOffset(int)
*/
public int getEndOffset() {
return end;
}
/**
* Returns the parent code block.
*
* @return The parent code block, or <code>null</code> if there isn't one.
*/
public CodeBlock getParent() {
return parent;
}
/**
* Returns the start offset of this code block.
*
* @return The start offset.
* @see #getEndOffset()
*/
public int getStartOffset() {
return start;
}
/**
* Returns a variable declaration.
*
* @param index The index of the declaration.
* @return The declaration.
* @see #getVariableDeclarationCount()
*/
public VariableDeclaration getVariableDeclaration(int index) {
return (VariableDeclaration)varDecs.get(index);
}
/**
* Returns the number of variable declarations in this code block.
*
* @return The number of variable declarations.
* @see #getVariableDeclaration(int)
*/
public int getVariableDeclarationCount() {
return varDecs==null ? 0 : varDecs.size();
}
/**
* Returns all local variables declared before a given offset, both in
* this code block and in all parent blocks.
*
* @param offs The offset.
* @return The {@link VariableDeclaration}s, or an empty list of none were
* declared before the offset.
*/
public List getVariableDeclarationsBefore(int offs) {
List vars = new ArrayList();
int varCount = getVariableDeclarationCount();
for (int i=0; i<varCount; i++) {
VariableDeclaration localVar = getVariableDeclaration(i);
if (localVar.getOffset()<offs) {
vars.add(localVar);
}
else {
break;
}
}
if (parent!=null) {
vars.addAll(parent.getVariableDeclarationsBefore(offs));
}
return vars;
}
/**
* Sets the end offset of this code block.
*
* @param end The end offset.
* @see #getEndOffset()
*/
public void setEndOffset(int end) {
this.end = end;
}
}