com.base4j.util.IoUtil Maven / Gradle / Ivy
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package com.base4j.util;
import java.io.BufferedReader;
import java.io.ByteArrayInputStream;
import java.io.Closeable;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.Reader;
import java.io.UnsupportedEncodingException;
import java.io.Writer;
import java.nio.CharBuffer;
import java.nio.MappedByteBuffer;
import java.nio.channels.FileChannel;
import java.nio.charset.Charset;
import java.util.Collection;
import com.base4j.util.exceptions.UtilException;
import com.base4j.util.io.FastByteArrayOutputStream;
import com.base4j.util.lang.Conver;
/**
* IO工具类
*
* @author xxx
*/
public class IoUtil {
/**
* 默认缓存大小
*/
public final static int DEFAULT_BUFFER_SIZE = 1024;
//-------------------------------------------------------------------------------------- Copy start
/**
* 将Reader中的内容复制到Writer中
* 使用默认缓存大小
*
* @param reader Reader
* @param writer Writer
* @return 拷贝的字节数
* @throws IOException
*/
public static long copy(Reader reader, Writer writer) throws IOException {
return copy(reader, writer, DEFAULT_BUFFER_SIZE);
}
/**
* 将Reader中的内容复制到Writer中
*
* @param reader Reader
* @param writer Writer
* @param bufferSize 缓存大小
* @return 传输的byte数
* @throws IOException
*/
public static long copy(Reader reader, Writer writer, int bufferSize) throws IOException {
char[] buffer = new char[bufferSize];
long count = 0;
int readSize;
while ((readSize = reader.read(buffer, 0, bufferSize)) >= 0) {
writer.write(buffer, 0, readSize);
count += readSize;
writer.flush();
}
return count;
}
/**
* 拷贝流，使用默认Buffer大小
*
* @param in 输入流
* @param out 输出流
* @return 传输的byte数
* @throws IOException
*/
public static long copy(InputStream in, OutputStream out) throws IOException {
return copy(in, out, DEFAULT_BUFFER_SIZE);
}
/**
* 拷贝流
*
* @param in 输入流
* @param out 输出流
* @param bufferSize 缓存大小
* @return 传输的byte数
* @throws IOException
*/
public static long copy(InputStream in, OutputStream out, int bufferSize) throws IOException {
byte[] buffer = new byte[bufferSize];
long count = 0;
for (int n = -1; (n = in.read(buffer)) != -1; ) {
out.write(buffer, 0, n);
count += n;
out.flush();
}
return count;
}
/**
* 拷贝文件流，使用NIO
*
* @param in 输入
* @param out 输出
* @return 拷贝的字节数
* @throws IOException
*/
public static long copy(FileInputStream in, FileOutputStream out) throws IOException {
FileChannel inChannel = in.getChannel();
FileChannel outChannel = out.getChannel();
return inChannel.transferTo(0, inChannel.size(), outChannel);
}
//-------------------------------------------------------------------------------------- Copy end
/**
* 获得一个文件读取器
*
* @param in 输入流
* @param charsetName 字符集名称
* @return BufferedReader对象
* @throws IOException
*/
public static BufferedReader getReader(InputStream in, String charsetName) throws IOException {
return getReader(in, Charset.forName(charsetName));
}
/**
* 获得一个文件读取器
*
* @param in 输入流
* @param charset 字符集
* @return BufferedReader对象
* @throws IOException
*/
public static BufferedReader getReader(InputStream in, Charset charset) throws IOException {
if (null == in) {
return null;
}
InputStreamReader reader = null;
if (null == charset) {
reader = new InputStreamReader(in);
} else {
reader = new InputStreamReader(in, charset);
}
return new BufferedReader(reader);
}
/**
* 从流中读取bytes
*
* @param in 输入流
* @return bytes
* @throws IOException
*/
public static byte[] readBytes(InputStream in) throws IOException {
final FastByteArrayOutputStream out = new FastByteArrayOutputStream();
copy(in, out);
return out.toByteArray();
}
/**
* 从流中读取内容
*
* @param in 输入流
* @param charset 字符集
* @return 内容
* @throws IOException
*/
public static String read(InputStream in, String charset) throws IOException {
final FastByteArrayOutputStream out = new FastByteArrayOutputStream();
copy(in, out);
return out.toString(charset);
}
/**
* 从Reader中读取String
*
* @param reader Reader
* @return String
* @throws IOException
*/
public static String read(Reader reader) throws IOException {
final StringBuilder builder = StrUtil.builder();
final CharBuffer buffer = CharBuffer.allocate(DEFAULT_BUFFER_SIZE);
while (-1 != reader.read(buffer)) {
builder.append(buffer.flip().toString());
}
return builder.toString();
}
/**
* 从FileChannel中读取内容
*
* @param fileChannel 文件管道
* @param charset 字符集
* @return 内容
* @throws IOException
*/
public static String read(FileChannel fileChannel, String charset) throws IOException {
final MappedByteBuffer buffer = fileChannel.map(FileChannel.MapMode.READ_ONLY, 0, fileChannel.size()).load();
return StrUtil.str(buffer, charset);
}
/**
* 从流中读取内容
*
* @param in 输入流
* @param charset 字符集
* @param collection 返回集合
* @return 内容
* @throws IOException
*/
public static > T readLines(InputStream in, String charset, T collection) throws IOException {
// 从返回的内容中读取所需内容
BufferedReader reader = new BufferedReader(new InputStreamReader(in, charset));
String line = null;
while ((line = reader.readLine()) != null) {
collection.add(line);
}
return collection;
}
/**
* String 转为 流
*
* @param content 内容
* @param charset 编码
* @return 字节流
*/
public static ByteArrayInputStream toStream(String content, String charset) {
if (content == null) {
return null;
}
byte[] data = null;
try {
data = StrUtil.isBlank(charset) ? content.getBytes() : content.getBytes(charset);
} catch (UnsupportedEncodingException e) {
throw new UtilException(StrUtil.format("Invalid charset [{}] !", charset), e);
}
return new ByteArrayInputStream(data);
}
/**
* 将多部分内容写到流中，自动转换为字符串
*
* @param out 输出流
* @param charset 写出的内容的字符集
* @param isCloseOut 写入完毕是否关闭输出流
* @param contents 写入的内容，调用toString()方法，不包括不会自动换行
* @throws IOException
*/
public static void write(OutputStream out, String charset, boolean isCloseOut, Object... contents) throws IOException {
OutputStreamWriter osw = null;
try {
osw = new OutputStreamWriter(out, charset);
for (Object content : contents) {
if (content != null) {
osw.write(Conver.toStr(content, StrUtil.EMPTY));
osw.flush();
}
}
} catch (Exception e) {
throw new IOException("Write content to OutputStream error!", e);
} finally {
if (isCloseOut) {
close(osw);
}
}
}
/**
* 打印内容，调用系统的System.out.println方法
*
* @param content 内容，会调用toString方法， 当内容中有 {} 表示变量占位符
* @param param 参数
*/
public static void echo(Object content, Object... param) {
if (content == null) {
System.out.println(content);
}
System.out.println(StrUtil.format(content.toString(), param));
}
/**
* 关闭
*
* @param closeable 被关闭的对象
*/
public static void close(Closeable closeable) {
if (closeable == null) {
return;
}
try {
closeable.close();
} catch (Exception e) {
}
}
/**
* 关闭
*
* @param closeable 被关闭的对象
* @since 1.7
*/
public static void close(AutoCloseable closeable) {
if (closeable == null) {
return;
}
try {
closeable.close();
} catch (Exception e) {
}
}
}