/*
* Copyright (C) 2012 www.amsoft.cn
*
* 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 com.ab.util;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.EOFException;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
// TODO: Auto-generated Javadoc
/**
*
* © 2012 amsoft.cn
* 名称：AbStreamUtil.java
* 描述：流工具类
* @author 还如一梦中
* @date 2015年4月3日 下午1:42:44
* @version v1.0
*/
public class AbStreamUtil {
/**
* 获取ByteArrayInputStream.
*
* @param buf the buf
* @return the input stream
*/
public static InputStream bytes2Stream(byte[] buf) {
return new ByteArrayInputStream(buf);
}
/**
* 从流中读取数据到byte[]..
*
* @param inStream the in stream
* @return the byte[]
* @throws IOException Signals that an I/O exception has occurred.
*/
public static byte[] stream2bytes(InputStream inStream) throws IOException {
byte[] buff = new byte[1024];
byte[] data = null;
try {
ByteArrayOutputStream swapStream = new ByteArrayOutputStream();
int read = 0;
while ((read = inStream.read(buff, 0, 100)) > 0) {
swapStream.write(buff, 0, read);
}
data = swapStream.toByteArray();
} catch (Exception e) {
e.printStackTrace();
}
return data;
}
/**
* 从流中读取指定的长度到byte[].
*
* @param in the in
* @param length the length
* @return the byte[]
* @throws IOException Signals that an I/O exception has occurred.
*/
public static byte[] stream2Bytes(InputStream in, int length) throws IOException {
byte[] bytes = new byte[length];
int count;
int pos = 0;
while (pos < length && ((count = in.read(bytes, pos, length - pos)) != -1)) {
pos += count;
}
if (pos != length) {
throw new IOException("Expected " + length + " bytes, read " + pos + " bytes");
}
return bytes;
}
/**
* Simple wrapper around {@link InputStream#read()} that throws EOFException
* instead of returning -1.
*
* @param is the is
* @return the int
* @throws IOException Signals that an I/O exception has occurred.
*/
public static int read(InputStream is) throws IOException {
int b = is.read();
if (b == -1) {
throw new EOFException();
}
return b;
}
/**
* Write int.
*
* @param os the os
* @param n the n
* @throws IOException Signals that an I/O exception has occurred.
*/
public static void writeInt(OutputStream os, int n) throws IOException {
os.write((n >> 0) & 0xff);
os.write((n >> 8) & 0xff);
os.write((n >> 16) & 0xff);
os.write((n >> 24) & 0xff);
}
/**
* Read int.
*
* @param is the is
* @return the int
* @throws IOException Signals that an I/O exception has occurred.
*/
public static int readInt(InputStream is) throws IOException {
int n = 0;
n |= (read(is) << 0);
n |= (read(is) << 8);
n |= (read(is) << 16);
n |= (read(is) << 24);
return n;
}
/**
* Write long.
*
* @param os the os
* @param n the n
* @throws IOException Signals that an I/O exception has occurred.
*/
public static void writeLong(OutputStream os, long n) throws IOException {
os.write((byte)(n >>> 0));
os.write((byte)(n >>> 8));
os.write((byte)(n >>> 16));
os.write((byte)(n >>> 24));
os.write((byte)(n >>> 32));
os.write((byte)(n >>> 40));
os.write((byte)(n >>> 48));
os.write((byte)(n >>> 56));
}
/**
* Read long.
*
* @param is the is
* @return the long
* @throws IOException Signals that an I/O exception has occurred.
*/
public static long readLong(InputStream is) throws IOException {
long n = 0;
n |= ((read(is) & 0xFFL) << 0);
n |= ((read(is) & 0xFFL) << 8);
n |= ((read(is) & 0xFFL) << 16);
n |= ((read(is) & 0xFFL) << 24);
n |= ((read(is) & 0xFFL) << 32);
n |= ((read(is) & 0xFFL) << 40);
n |= ((read(is) & 0xFFL) << 48);
n |= ((read(is) & 0xFFL) << 56);
return n;
}
/**
* Write string.
*
* @param os the os
* @param s the s
* @throws IOException Signals that an I/O exception has occurred.
*/
public static void writeString(OutputStream os, String s) throws IOException {
byte[] b = s.getBytes("UTF-8");
writeLong(os, b.length);
os.write(b, 0, b.length);
}
/**
* Read string.
*
* @param is the is
* @return the string
* @throws IOException Signals that an I/O exception has occurred.
*/
public static String readString(InputStream is) throws IOException {
int n = (int) readLong(is);
byte[] b = AbStreamUtil.stream2Bytes(is, n);
return new String(b, "UTF-8");
}
/**
* Write string string map.
*
* @param map the map
* @param os the os
* @throws IOException Signals that an I/O exception has occurred.
*/
public static void writeStringStringMap(Map<String, String> map, OutputStream os) throws IOException {
if (map != null) {
writeInt(os, map.size());
for (Map.Entry<String, String> entry : map.entrySet()) {
writeString(os, entry.getKey());
writeString(os, entry.getValue());
}
} else {
writeInt(os, 0);
}
}
/**
* Read string string map.
*
* @param is the is
* @return the map
* @throws IOException Signals that an I/O exception has occurred.
*/
public static Map<String, String> readStringStringMap(InputStream is) throws IOException {
int size = readInt(is);
Map<String, String> result = (size == 0)
? Collections.<String, String>emptyMap()
: new HashMap<String, String>(size);
for (int i = 0; i < size; i++) {
String key = readString(is).intern();
String value = readString(is).intern();
result.put(key, value);
}
return result;
}
}