Java Tutorial/File/Text File
Версия от 17:44, 31 мая 2010; (обсуждение)
Содержание
- 1 Dump a String to a text file with encoding.
- 2 Gets the content from a File as String Array List
- 3 Load a text file contents as a String.
- 4 Load File As Text
- 5 Load file content to List
- 6 Load file line by line
- 7 Read and return the entire contents of the supplied File.
- 8 Read ByteArrayInputStream to String
- 9 ReadLines: read file to list of strings
- 10 Read string from InputStream and Reader
- 11 Read the contents of a file and place them in a string object.
- 12 Searches case sensitively in a file
Dump a String to a text file with encoding.
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
import java.io.File;
import java.io.FileOutputStream;
import java.io.FileWriter;
import java.io.IOException;
import java.io.OutputStreamWriter;
import java.io.Writer;
public class Main {
/**
* Dump a <code>String</code> to a text file.
*
* @param file The output file
* @param string The string to be dumped
* @param encoding The encoding for the output file or null for default platform encoding
* @exception IOException IO Error
*/
public static void serializeString(File file, String string, String encoding)
throws IOException {
final Writer fw =
(encoding == null)?
new FileWriter(file):
new OutputStreamWriter(new FileOutputStream(file), encoding);
try {
fw.write(string);
fw.flush();
} finally {
fw.close();
}
}
}
Gets the content from a File as String Array List
import java.io.BufferedReader;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FilenameFilter;
import java.io.IOException;
import java.net.URL;
import java.util.ArrayList;
import java.util.Iterator;
/*
* IzPack - Copyright 2001-2008 Julien Ponge, All Rights Reserved.
*
* http://izpack.org/
* http://izpack.codehaus.org/
*
* Copyright 2005 Marc Eppelmann
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/**
* Provides general global file utility methods
*
* @author marc.eppelmann
*/
class FileUtil
{
//~ Constructors ***********************************************************************
/**
* Creates a new FileUtil object.
*/
public FileUtil()
{
}
//~ Methods ****************************************************************************
/**
* Gets the content from a File as StringArray List.
*
* @param fileName A file to read from.
* @return List of individual line of the specified file. List may be empty but not
* null.
* @throws IOException
*/
public static ArrayList getFileContent(String fileName)
throws IOException
{
ArrayList result = new ArrayList();
File aFile = new File(fileName);
if (!aFile.isFile())
{
//throw new IOException( fileName + " is not a regular File" );
return result; // None
}
BufferedReader reader = null;
try
{
reader = new BufferedReader(new FileReader(aFile));
}
catch (FileNotFoundException e1)
{
// TODO handle Exception
e1.printStackTrace();
return result;
}
String aLine = null;
while ((aLine = reader.readLine()) != null)
{
result.add(aLine + "\n");
}
reader.close();
return result;
}
/**
* Searches case sensitively, and returns true if the given SearchString occurs in the
* first File with the given Filename.
*
* @param aFileName A files name
* @param aSearchString the string search for
* @return true if found in the file otherwise false
*/
public static boolean fileContains(String aFileName, String aSearchString)
{
return (fileContains(aFileName, aSearchString, false));
}
/**
* Tests if the given File contains the given Search String
*
* @param aFileName A files name
* @param aSearchString the String to search for
* @param caseInSensitiveSearch If false the Search is casesensitive
* @return true if found in the file otherwise false
*/
public static boolean fileContains(String aFileName, String aSearchString,
boolean caseInSensitiveSearch)
{
boolean result = false;
String searchString = caseInSensitiveSearch
? aSearchString.toLowerCase() : aSearchString;
ArrayList fileContent = new ArrayList();
try
{
fileContent = getFileContent(aFileName);
}
catch (IOException e)
{
// TODO handle Exception
e.printStackTrace();
}
Iterator linesIter = fileContent.iterator();
while (linesIter.hasNext())
{
String currentline = (String) linesIter.next();
if (caseInSensitiveSearch)
{
currentline = currentline.toLowerCase();
}
if (currentline.indexOf(searchString) > -1)
{
result = true;
break;
}
}
return result;
}
/**
* Gets file date and time.
*
* @param url The URL of the file for which date and time will be returned.
* @return Returns long value which is the date and time of the file. If any error
* occures returns -1 (=no file date and time available).
*/
public static long getFileDateTime(URL url)
{
if (url == null)
{
return -1;
}
String fileName = url.getFile();
if (fileName.charAt(0) == "/" || fileName.charAt(0) == "\\")
{
fileName = fileName.substring(1, fileName.length());
}
try
{
File file = new File(fileName);
// File name must be a file or a directory.
if (!file.isDirectory() && !file.isFile())
{
return -1;
}
return file.lastModified();
}
catch (java.lang.Exception e)
{ // Trap all Exception based exceptions and return -1.
return -1;
}
}
public static String[] getFileNames(String dirPath) throws Exception
{
return getFileNames(dirPath, null);
}
public static String[] getFileNames(String dirPath, FilenameFilter fileNameFilter) throws Exception
{
String fileNames[] = null;
File dir = new File(dirPath);
if (dir.isDirectory())
{
if (fileNameFilter != null)
{
fileNames = dir.list(fileNameFilter);
}
else
{
fileNames = dir.list();
}
}
return fileNames;
}
/**
* Test main
*
* @param args
*/
public static void main(String[] args)
{
}
}
Load a text file contents as a String.
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
import java.io.File;
import java.io.FileReader;
import java.io.IOException;
public class Main {
/**
* Load a text file contents as a <code>String<code>.
* This method does not perform enconding conversions
*
* @param file The input file
* @return The file contents as a <code>String</code>
* @exception IOException IO Error
*/
public static String deserializeString(File file)
throws IOException {
int len;
char[] chr = new char[4096];
final StringBuffer buffer = new StringBuffer();
final FileReader reader = new FileReader(file);
try {
while ((len = reader.read(chr)) > 0) {
buffer.append(chr, 0, len);
}
} finally {
reader.close();
}
return buffer.toString();
}
}
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();
}
}
}
Load file content to List
/*
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();
}
}
}
Load file line by line
/*
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();
}
}
}
Read and return the entire contents of the supplied File.
/*
* JBoss DNA (http://www.jboss.org/dna)
* See the COPYRIGHT.txt file distributed with this work for information
* regarding copyright ownership. Some portions may be licensed
* to Red Hat, Inc. under one or more contributor license agreements.
* See the AUTHORS.txt file in the distribution for a full listing of
* individual contributors.
*
* JBoss DNA is free software. Unless otherwise indicated, all code in JBoss DNA
* is licensed to you 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.
*
* JBoss DNA 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 software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
import java.io.File;
import java.io.FileReader;
import java.io.IOException;
import java.io.Reader;
/**
* @author Randall Hauch
*/
public class Main {
/**
* Read and return the entire contents of the supplied {@link File}.
*
* @param file the file containing the information to be read; may be null
* @return the contents, or an empty string if the supplied reader is null
* @throws IOException if there is an error reading the content
*/
public static String read( File file ) throws IOException {
if (file == null) return "";
StringBuilder sb = new StringBuilder();
boolean error = false;
Reader reader = new FileReader(file);
try {
int numRead = 0;
char[] buffer = new char[1024];
while ((numRead = reader.read(buffer)) > -1) {
sb.append(buffer, 0, numRead);
}
} catch (IOException e) {
error = true; // this error should be thrown, even if there is an error closing reader
throw e;
} catch (RuntimeException e) {
error = true; // this error should be thrown, even if there is an error closing reader
throw e;
} finally {
try {
reader.close();
} catch (IOException e) {
if (!error) throw e;
}
}
return sb.toString();
}
}
Read ByteArrayInputStream to String
import java.io.ByteArrayInputStream;
/*
* The contents of this file are subject to the terms
* of the Common Development and Distribution License
* (the "License"). You may not use this file except
* in compliance with the License.
*
* You can obtain a copy of the license at
* glassfish/bootstrap/legal/CDDLv1.0.txt or
* https://glassfish.dev.java.net/public/CDDLv1.0.html.
* See the License for the specific language governing
* permissions and limitations under the License.
*
* When distributing Covered Code, include this CDDL
* HEADER in each file and include the License file at
* glassfish/bootstrap/legal/CDDLv1.0.txt. If applicable,
* add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your
* own identifying information: Portions Copyright [yyyy]
* [name of copyright owner]
*/
/*
* @(#)ASCIIUtility.java 1.10 05/08/29
*
* Copyright 1997-2005 Sun Microsystems, Inc. All Rights Reserved.
*/
public class Utils {
public static String toString(ByteArrayInputStream is) {
int size = is.available();
char[] theChars = new char[size];
byte[] bytes = new byte[size];
is.read(bytes, 0, size);
for (int i = 0; i < size;)
theChars[i] = (char)(bytes[i++]&0xff);
return new String(theChars);
}
}
ReadLines: read file to list of strings
import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.util.ArrayList;
import java.util.List;
public class Utils {
public static List<String> readLines(File file) throws Exception {
if (!file.exists()) {
return new ArrayList<String>();
}
BufferedReader reader = new BufferedReader(new FileReader(file));
List<String> results = new ArrayList<String>();
String line = reader.readLine();
while (line != null) {
results.add(line);
line = reader.readLine();
}
return results;
}
}
Read string from InputStream and Reader
/*
* $RCSfile: StringIO.java,v $
*
* Copyright (c) 2007 Sun Microsystems, Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistribution of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* - Redistribution in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* Neither the name of Sun Microsystems, Inc. or the names of
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* This software is provided "AS IS," without a warranty of any
* kind. ALL EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND
* WARRANTIES, INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT, ARE HEREBY
* EXCLUDED. SUN MICROSYSTEMS, INC. ("SUN") AND ITS LICENSORS SHALL
* NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF
* USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS
* DERIVATIVES. IN NO EVENT WILL SUN OR ITS LICENSORS BE LIABLE FOR
* ANY LOST REVENUE, PROFIT OR DATA, OR FOR DIRECT, INDIRECT, SPECIAL,
* CONSEQUENTIAL, INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER CAUSED AND
* REGARDLESS OF THE THEORY OF LIABILITY, ARISING OUT OF THE USE OF OR
* INABILITY TO USE THIS SOFTWARE, EVEN IF SUN HAS BEEN ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGES.
*
* You acknowledge that this software is not designed, licensed or
* intended for use in the design, construction, operation or
* maintenance of any nuclear facility.
*
* $Revision: 1.4 $
* $Date: 2007/02/09 17:20:42 $
* $State: Exp $
*/
import java.io.IOException;
import java.io.File;
import java.io.FileReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.Reader;
import java.net.URL;
/**
* Utility class with static methods to read the entire contents of a
* file, URL, InputStream, or Reader into a single String that is
* returned to the user.
*
* @since Java 3D 1.4
*/
public class StringIO {
/**
* Read the entire contents of the specified file and return a
* single String object containing the contents of the file.
*
* @param fileName the name of the file from which to read
*
* @return a String containing the contents of the input file
*
* @throws IOException if the specified file cannot be opened, or
* if an I/O error occurs while reading the file
*/
public static String readFully(String fileName) throws IOException {
return readFully(new File(fileName));
}
/**
* Read the entire contents of the specified file and return a
* single String object containing the contents of the file.
* This method does not return until the end of the input file
* is reached.
*
* @param file a File from which to read
*
* @return a String containing the contents of the input file
*
* @throws IOException if the specified file cannot be opened, or
* if an I/O error occurs while reading the file
*/
public static String readFully(File file) throws IOException {
return readFully(new FileReader(file));
}
/**
* Read the entire contents of the specified URL and return a
* single String object containing the contents of the URL.
* This method does not return until an end of stream is reached
* for the URL.
*
* @param url a URL from which to read
*
* @return a String containing the contents of the input URL
*
* @throws IOException if the specified URL cannot be opened, or
* if an I/O error occurs while reading the URL
*/
public static String readFully(URL url) throws IOException {
return readFully(url.openStream());
}
/**
* Read the entire contents of the specified InputStream and return a
* single String object containing the contents of the InputStream.
* This method does not return until the end of the input
* stream is reached.
*
* @param stream an InputStream from which to read
*
* @return a String containing the contents of the input stream
*
* @throws IOException if an I/O error occurs while reading the input stream
*/
public static String readFully(InputStream stream) throws IOException {
return readFully(new InputStreamReader(stream));
}
/**
* Read the entire contents of the specified Reader and return a
* single String object containing the contents of the InputStream.
* This method does not return until the end of the input file or
* stream is reached.
*
* @param reader a Reader from which to read
*
* @return a String containing the contents of the stream
*
* @throws IOException if an I/O error occurs while reading the input stream
*/
public static String readFully(Reader reader) throws IOException {
char[] arr = new char[8*1024]; // 8K at a time
StringBuffer buf = new StringBuffer();
int numChars;
while ((numChars = reader.read(arr, 0, arr.length)) > 0) {
buf.append(arr, 0, numChars);
}
return buf.toString();
}
/**
* Do not construct an instance of this class.
*/
private StringIO() {
}
}
Read the contents of a file and place them in a string object.
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
import java.io.File;
import java.io.FileReader;
/**
*
* @author
* @version $Id: StringUtils.java 685685 2008-08-13 21:43:27Z nbubna $
*/
public class Main {
/**
* Read the contents of a file and place them in
* a string object.
*
* @param file path to file.
* @return String contents of the file.
*/
public static String fileContentsToString(String file)
{
String contents = "";
File f = null;
try
{
f = new File(file);
if (f.exists())
{
FileReader fr = null;
try
{
fr = new FileReader(f);
char[] template = new char[(int) f.length()];
fr.read(template);
contents = new String(template);
}
catch (Exception e)
{
e.printStackTrace();
}
finally
{
if (fr != null)
{
fr.close();
}
}
}
}
catch (Exception e)
{
e.printStackTrace();
}
return contents;
}
}
Searches case sensitively in a file
import java.io.BufferedReader;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FilenameFilter;
import java.io.IOException;
import java.net.URL;
import java.util.ArrayList;
import java.util.Iterator;
/*
* IzPack - Copyright 2001-2008 Julien Ponge, All Rights Reserved.
*
* http://izpack.org/
* http://izpack.codehaus.org/
*
* Copyright 2005 Marc Eppelmann
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/**
* Provides general global file utility methods
*
* @author marc.eppelmann
*/
class FileUtil
{
//~ Constructors ***********************************************************************
/**
* Creates a new FileUtil object.
*/
public FileUtil()
{
}
//~ Methods ****************************************************************************
/**
* Gets the content from a File as StringArray List.
*
* @param fileName A file to read from.
* @return List of individual line of the specified file. List may be empty but not
* null.
* @throws IOException
*/
public static ArrayList getFileContent(String fileName)
throws IOException
{
ArrayList result = new ArrayList();
File aFile = new File(fileName);
if (!aFile.isFile())
{
//throw new IOException( fileName + " is not a regular File" );
return result; // None
}
BufferedReader reader = null;
try
{
reader = new BufferedReader(new FileReader(aFile));
}
catch (FileNotFoundException e1)
{
// TODO handle Exception
e1.printStackTrace();
return result;
}
String aLine = null;
while ((aLine = reader.readLine()) != null)
{
result.add(aLine + "\n");
}
reader.close();
return result;
}
/**
* Searches case sensitively, and returns true if the given SearchString occurs in the
* first File with the given Filename.
*
* @param aFileName A files name
* @param aSearchString the string search for
* @return true if found in the file otherwise false
*/
public static boolean fileContains(String aFileName, String aSearchString)
{
return (fileContains(aFileName, aSearchString, false));
}
/**
* Tests if the given File contains the given Search String
*
* @param aFileName A files name
* @param aSearchString the String to search for
* @param caseInSensitiveSearch If false the Search is casesensitive
* @return true if found in the file otherwise false
*/
public static boolean fileContains(String aFileName, String aSearchString,
boolean caseInSensitiveSearch)
{
boolean result = false;
String searchString = caseInSensitiveSearch
? aSearchString.toLowerCase() : aSearchString;
ArrayList fileContent = new ArrayList();
try
{
fileContent = getFileContent(aFileName);
}
catch (IOException e)
{
// TODO handle Exception
e.printStackTrace();
}
Iterator linesIter = fileContent.iterator();
while (linesIter.hasNext())
{
String currentline = (String) linesIter.next();
if (caseInSensitiveSearch)
{
currentline = currentline.toLowerCase();
}
if (currentline.indexOf(searchString) > -1)
{
result = true;
break;
}
}
return result;
}
/**
* Gets file date and time.
*
* @param url The URL of the file for which date and time will be returned.
* @return Returns long value which is the date and time of the file. If any error
* occures returns -1 (=no file date and time available).
*/
public static long getFileDateTime(URL url)
{
if (url == null)
{
return -1;
}
String fileName = url.getFile();
if (fileName.charAt(0) == "/" || fileName.charAt(0) == "\\")
{
fileName = fileName.substring(1, fileName.length());
}
try
{
File file = new File(fileName);
// File name must be a file or a directory.
if (!file.isDirectory() && !file.isFile())
{
return -1;
}
return file.lastModified();
}
catch (java.lang.Exception e)
{ // Trap all Exception based exceptions and return -1.
return -1;
}
}
public static String[] getFileNames(String dirPath) throws Exception
{
return getFileNames(dirPath, null);
}
public static String[] getFileNames(String dirPath, FilenameFilter fileNameFilter) throws Exception
{
String fileNames[] = null;
File dir = new File(dirPath);
if (dir.isDirectory())
{
if (fileNameFilter != null)
{
fileNames = dir.list(fileNameFilter);
}
else
{
fileNames = dir.list();
}
}
return fileNames;
}
/**
* Test main
*
* @param args
*/
public static void main(String[] args)
{
}
}
