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package submit;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import submit.ast.VarType;
/*
* Code formatter project
* CS 4481
*/
/**
*
*/
public class SymbolTable {
private final HashMap<String, SymbolInfo> table;
private SymbolTable parent;
private final List<SymbolTable> children;
private int offset;
public static int LABEL_IDENTIFIER = 0;
public static String nextId() {
return Integer.toString(SymbolTable.LABEL_IDENTIFIER++);
}
public SymbolTable() {
offset = 0;
table = new HashMap<>();
parent = null;
children = new ArrayList<>();
this.addGlobalSymbols();
}
public List<String> symbolNames() { return new ArrayList<>(table.keySet()); }
public void addGlobalSymbols() {
SymbolInfo println = new SymbolInfo("println", null, true);
this.addSymbol("println", println);
}
public void addSymbol(String id, SymbolInfo symbol) { table.put(id, symbol); }
public int addOffset(int n) {
offset -= 4 * n;
return offset;
}
public int getOffset() { return this.offset; }
// Add symbols in before and reorder offsets such that symbols in before have
// a "higher" offset
public void addOtherTableBefore(SymbolTable before) {
offset = 0;
List<String> thisSymbols = symbolNames();
for (String id : before.symbolNames()) {
SymbolInfo symbol = before.find(id);
if (!symbol.isFunction()) {
addOffset(1);
symbol.setOffset(offset);
}
addSymbol(id, symbol);
}
for (String id : thisSymbols) {
SymbolInfo symbol = table.get(id);
if (!symbol.isFunction()) {
addOffset(1);
table.get(id).setOffset(offset);
}
}
}
public int offsetOf(String id) {
if (table.containsKey(id)) {
return table.get(id).getOffset();
}
if (parent != null) {
return -parent.getOffset() + parent.offsetOf(id);
}
return 0; // This shouldn't happen :D
}
/**
* Returns null if no symbol with that id is in this symbol table or an
* ancestor table.
*
* @param id
* @return
*/
public SymbolInfo find(String id) {
if (table.containsKey(id)) {
return table.get(id);
}
if (parent != null) {
return parent.find(id);
}
return null;
}
/**
* Returns the new child.
*
* @return
*/
public SymbolTable createChild() {
SymbolTable child = new SymbolTable();
children.add(child);
child.parent = this;
return child;
}
public SymbolTable getParent() { return parent; }
}
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