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package org.antlr.runtime;

import java.io.*;

This is a char buffer stream that is loaded from a file all at once when you construct the object. This looks very much like an ANTLReader or ANTLRInputStream, but it's a special case since we know the exact size of the object to load. We can avoid lots of data copying.
/** This is a char buffer stream that is loaded from a file * all at once when you construct the object. This looks very * much like an ANTLReader or ANTLRInputStream, but it's a special case * since we know the exact size of the object to load. We can avoid lots * of data copying. */
public class ANTLRFileStream extends ANTLRStringStream { protected String fileName; public ANTLRFileStream(String fileName) throws IOException { this(fileName, null); } public ANTLRFileStream(String fileName, String encoding) throws IOException { this.fileName = fileName; load(fileName, encoding); } public void load(String fileName, String encoding) throws IOException { if ( fileName==null ) { return; } File f = new File(fileName); int size = (int)f.length(); InputStreamReader isr; FileInputStream fis = new FileInputStream(fileName); if ( encoding!=null ) { isr = new InputStreamReader(fis, encoding); } else { isr = new InputStreamReader(fis); } try { data = new char[size]; super.n = isr.read(data); } finally { isr.close(); } } @Override public String getSourceName() { return fileName; } }