Load File As Text
/*
GNU LESSER GENERAL PUBLIC LICENSE
Copyright (C) 2006 The Lobo Project
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
This library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
Contact info: lobochief@users.sourceforge.net
*/
/*
* Created on Mar 19, 2005
*/
import java.io.*;
/**
* @author J. H. S.
*/
public class IORoutines {
public static final byte[] LINE_BREAK_BYTES = { (byte) 13, (byte) 10 };
public static String loadAsText(InputStream in, String encoding) throws IOException {
return loadAsText(in, encoding, 4096);
}
public static String loadAsText(InputStream in, String encoding, int bufferSize) throws IOException {
InputStreamReader reader = new InputStreamReader(in, encoding);
char[] buffer = new char[bufferSize];
int offset = 0;
for(;;) {
int remain = buffer.length - offset;
if(remain <= 0) {
char[] newBuffer = new char[buffer.length * 2];
System.arraycopy(buffer, 0, newBuffer, 0, offset);
buffer = newBuffer;
remain = buffer.length - offset;
}
int numRead = reader.read(buffer, offset, remain);
if(numRead == -1) {
break;
}
offset += numRead;
}
return new String(buffer, 0, offset);
}
public static byte[] load(File file) throws IOException {
long fileLength = file.length();
if(fileLength > Integer.MAX_VALUE) {
throw new IOException("File '" + file.getName() + "' too big");
}
InputStream in = new FileInputStream(file);
try {
return loadExact(in, (int) fileLength);
} finally {
in.close();
}
}
public static byte[] load(InputStream in) throws IOException {
return load(in, 4096);
}
public static byte[] load(InputStream in, int initialBufferSize) throws IOException {
if(initialBufferSize == 0) {
initialBufferSize = 1;
}
byte[] buffer = new byte[initialBufferSize];
int offset = 0;
for(;;) {
int remain = buffer.length - offset;
if(remain <= 0) {
int newSize = buffer.length * 2;
byte[] newBuffer = new byte[newSize];
System.arraycopy(buffer, 0, newBuffer, 0, offset);
buffer = newBuffer;
remain = buffer.length - offset;
}
int numRead = in.read(buffer, offset, remain);
if(numRead == -1) {
break;
}
offset += numRead;
}
if(offset < buffer.length) {
byte[] newBuffer = new byte[offset];
System.arraycopy(buffer, 0, newBuffer, 0, offset);
buffer = newBuffer;
}
return buffer;
}
public static byte[] loadExact(InputStream in, int length) throws IOException {
byte[] buffer = new byte[length];
int offset = 0;
for(;;) {
int remain = length - offset;
if(remain <= 0) {
break;
}
int numRead = in.read(buffer, offset, remain);
if(numRead == -1) {
throw new IOException("Reached EOF, read " + offset + " expecting " + length);
}
offset += numRead;
}
return buffer;
}
public static boolean equalContent(File file, byte[] content) throws IOException {
long length = file.length();
if(length > Integer.MAX_VALUE) {
throw new IOException("File '" + file + "' too big");
}
InputStream in = new FileInputStream(file);
try {
byte[] fileContent = loadExact(in, (int) length);
return java.util.Arrays.equals(content, fileContent);
} finally {
in.close();
}
}
public static void save(File file, byte[] content) throws IOException {
FileOutputStream out = new FileOutputStream(file);
try {
out.write(content);
} finally {
out.close();
}
}
/**
* Reads line without buffering.
*/
public static String readLine(InputStream in) throws IOException {
int b;
StringBuffer sb = null;
OUTER:
while((b = in.read()) != -1) {
if(sb == null) {
sb = new StringBuffer();
}
switch(b) {
case (byte) '\n':
break OUTER;
case (byte) '\r':
break;
default:
sb.append((char) b);
break;
}
}
return sb == null ? null : sb.toString();
}
public static void touch(File file) {
file.setLastModified(System.currentTimeMillis());
}
public static void saveStrings(File file, java.util.Collection list) throws IOException {
BufferedOutputStream bout = new BufferedOutputStream(new FileOutputStream(file));
try {
PrintWriter writer = new PrintWriter(bout);
java.util.Iterator i = list.iterator();
while(i.hasNext()) {
String text = (String) i.next();
writer.println(text);
}
writer.flush();
} finally {
bout.close();
}
}
public static java.util.List loadStrings(File file) throws IOException {
java.util.List list = new java.util.LinkedList();
InputStream in = new FileInputStream(file);
try {
BufferedReader reader = new BufferedReader(new InputStreamReader(in));
String line;
while((line = reader.readLine()) != null) {
list.add(line);
}
return list;
} finally {
in.close();
}
}
}
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