/*
* Copyright (C) 2007 The Android Open Source Project
*
* 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.
*/
package android.core;
import java.io.InputStream;
import java.io.IOException;
import java.io.Reader;
import java.io.InputStreamReader;
public final class IOUtil {
private IOUtil() {
}
/**
* returns the content of an InputStream as a String.
*
* @param a the input stream.
* @return the string
* @throws java.io.IOException
*/
public static String read(InputStream a) throws IOException {
int r;
StringBuilder builder = new StringBuilder();
do {
r = a.read();
if (r != -1)
builder.append((char) r);
} while (r != -1);
return builder.toString();
}
/**
* reads characters from a reader and returns them as a string.
*
* @param a the reader.
* @return the string.
* @throws IOException
*/
public static String read(Reader a) throws IOException {
int r;
StringBuilder builder = new StringBuilder();
do {
r = a.read();
if (r != -1)
builder.append((char) r);
} while (r != -1);
return builder.toString();
}
/**
* returns the content of an InputStream as a String. It reads x characters.
*
* @param a the input stream.
* @param x number of characters to read.
* @return the string
* @throws IOException
*/
public static String read(InputStream a, int x) throws IOException {
byte[] b = new byte[x];
int len = a.read(b, 0, x);
if (len < 0) {
return "";
}
return new String(b, 0, len);
}
/**
* reads a number of characters from a reader and returns them as a string.
*
* @param a the reader.
* @param x the number of characters to read.
* @return the string.
* @throws IOException
*/
public static String read(Reader a, int x) throws IOException {
char[] b = new char[x];
int len = a.read(b, 0, x);
if (len < 0) {
return "";
}
return new String(b, 0, len);
}
/**
* returns the content of the input stream as a String. It only appends
* every second character.
*
* @param a the input stream.
* @return the string created from every second character of the input stream.
* @throws IOException
*/
public static String skipRead(InputStream a) throws IOException {
int r;
StringBuilder builder = new StringBuilder();
do {
a.skip(1);
r = a.read();
if (r != -1)
builder.append((char) r);
} while (r != -1);
return builder.toString();
}
/**
* reads every second characters from a reader and returns them as a string.
*
* @param a the reader.
* @return the string.
* @throws IOException
*/
public static String skipRead(Reader a) throws IOException {
int r;
StringBuilder builder = new StringBuilder();
do {
a.skip(1);
r = a.read();
if (r != -1)
builder.append((char) r);
} while (r != -1);
return builder.toString();
}
/**
* reads characters from a InputStream, skips back y characters and continues
* reading from that new position up to the end.
*
* @param a the InputStream.
* @param x the position of the mark. the marks position is x+y
* @param y the number of characters to jump back after the position x+y was reached.
* @return the string.
* @throws IOException
*/
public static String markRead(InputStream a, int x, int y) throws IOException {
int m = 0;
int r;
StringBuilder builder = new StringBuilder();
do {
m++;
r = a.read();
if (m == x)
a.mark((x + y));
if (m == (x + y))
a.reset();
if (r != -1)
builder.append((char) r);
} while (r != -1);
return builder.toString();
}
/**
* reads characters from a reader, skips back y characters and continues
* reading from that new position up to the end.
*
* @param a the reader.
* @param x the position of the mark. the marks position is x+y
* @param y the number of characters to jump back after the position x+y was reached.
* @return the string.
* @throws IOException
*/
public static String markRead(Reader a, int x, int y) throws IOException {
int m = 0;
int r;
StringBuilder builder = new StringBuilder();
do {
m++;
r = a.read();
if (m == x)
a.mark((x + y));
if (m == (x + y))
a.reset();
if (r != -1)
builder.append((char) r);
} while (r != -1);
return builder.toString();
}
}
|