Android InputStream等通用转化总结初阶篇

最新推荐文章于 2024-10-16 16:15:46 发布

lightspear

最新推荐文章于 2024-10-16 16:15:46 发布

阅读量1.3k

点赞数 1

CC 4.0 BY-SA版权

分类专栏： android 文章标签： android InputStream 转换

本文链接：https://blog.youkuaiyun.com/lightspear/article/details/50814467

android 专栏收录该内容

3 篇文章

订阅专栏

本文提供了一系列关于Java及Android平台上的文件流操作方法，包括文件读写、字符串与流之间的转换、资源加载等常见任务的具体实现。适用于希望提高在不同平台上文件处理能力的开发者。

摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >

既然是初阶篇，为了区分Android上专用和JAVA的通用型分别分开贴出两个类的代码，以后如果发现更好更多将不定期更新

先是Java的基础转换

package com.java.pblib;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.nio.charset.Charset;



public class UtilsStream {

	static Charset defaultcharset = Charset.defaultCharset();

	public static byte[] InputStreamToBytes(InputStream in) throws IOException {
		ByteArrayOutputStream out = new ByteArrayOutputStream();
		byte[] buffer = new byte[1024 * 4];
		int n = 0;
		while ((n = in.read(buffer)) != -1) {
			out.write(buffer, 0, n);
		}
		return out.toByteArray();
	}

	public static String InputStreamToString(InputStream in, Charset charset) throws IOException {
		byte[] buff = InputStreamToBytes(in);
		return new String(buff, charset);
	}

	public static void InputStreamToFile(InputStream in, File file) throws IOException {
		OutputStream os = new FileOutputStream(file);
		int bytesRead = 0;
		byte[] buffer = new byte[1024 * 4];
		while ((bytesRead = in.read(buffer, 0, buffer.length)) != -1) {
			os.write(buffer, 0, bytesRead);
		}
		os.close();
		in.close();
	}

	public static InputStream StringToInputStream(String str, Charset charset) {
		ByteArrayInputStream stream = new ByteArrayInputStream(str.getBytes(charset));
		return stream;
	}

	public static InputStream FileToInputStream(File file) throws IOException {

		return new FileInputStream(file);
	}

}

接着是Android上用的常用通用转化

package com.android.pblib;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.InputStream;

import android.content.Context;
import android.graphics.*;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;



public class UtilsConvert {

	public static Bitmap InputStreamToBitmap(InputStream in) {
		return BitmapFactory.decodeStream(in);
	}

	public static Bitmap BytesToBitmap(byte[] b) {
		if (b.length != 0)
			return BitmapFactory.decodeByteArray(b, 0, b.length);
		else
			return null;
	}

	public static Bitmap DrawableToBitmap(Drawable drawable) {
		Bitmap bitmap = Bitmap.createBitmap(drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight(),
				drawable.getOpacity() != PixelFormat.OPAQUE ? Bitmap.Config.ARGB_8888 : Bitmap.Config.RGB_565);
		Canvas canvas = new Canvas(bitmap);
		drawable.setBounds(0, 0, drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight());
		drawable.draw(canvas);
		return bitmap;
	}

	public static Bitmap GetBitmapByResId(Context context,int resid){
		Bitmap bmp=BitmapFactory.decodeResource(context.getResources(), resid);
		return null;
	}
	
	public static byte[]  BimapTpBytes(Bitmap bm) {
		ByteArrayOutputStream baos = new ByteArrayOutputStream();
		bm.compress(Bitmap.CompressFormat.PNG, 100, baos);
		return baos.toByteArray();
	}
	
	public static InputStream BitmapToInputStream(Bitmap bm, int quality) {
		ByteArrayOutputStream baos = new ByteArrayOutputStream();
		bm.compress(Bitmap.CompressFormat.PNG, quality, baos);
		InputStream is = new ByteArrayInputStream(baos.toByteArray());
		return is;
	}
	// Bitmap转换成Drawable   
	public static Drawable BitmapToDrawable(Bitmap bitmap) {
		BitmapDrawable bd = new BitmapDrawable(bitmap);
		Drawable d = (Drawable) bd;
		return d;
	}

	
}