如何将servlet响应编码为base64？[副本]

Question

response.setContentType("image/jpeg");
ServletOutputStream out;  
out = response.getOutputStream();
FileInputStream fin = new FileInputStream("D:\\Astro\\html5up-arcana (1)\\images\\1.jpg");

BufferedInputStream bin = new BufferedInputStream(fin);  
BufferedOutputStream bout = new BufferedOutputStream(out);  
int ch =0; ;  
while((ch=bin.read())!=-1) {  
    bout.write(ch);  
}  

$(document).ready(function() {
    $('#nxt').click(function() {
        $.ajax({
            url : 'DisplayImage',
            data : {
                userName : 'Hi'
            },
            success : function(result) {
                $('#gallery-overlay').html('<img src="data:image/jpeg;base64,'+result+'"/>');
            }
        });
    });
});

Answer 1

>

使用java.util.base64JDK8

byte[] contents = new byte[1024];
int bytesRead = 0;
String strFileContents;
while ((bytesRead = bin.read(contents)) != -1) {
    bout.write(java.util.Base64.getEncoder().encode(contents), bytesRead);
}

使用sun.misc.base64Encoder，请注意：Oracle表示sun.*包不是受支持的公共接口的一部分。因此，请尽量避免使用此方法

sun.misc.BASE64Encoder encoder= new sun.misc.BASE64Encoder();
byte[] contents = new byte[1024];
int bytesRead = 0;
String strFileContents;
while ((bytesRead = bin.read(contents)) != -1) {
    bout.write(encoder.encode(contents).getBytes());
}

使用org.apache.commons.codec.binary.base64

byte[] contents = new byte[1024];
int bytesRead = 0;
while ((bytesRead = bin.read(contents)) != -1) {
    bout.write(org.apache.commons.codec.binary.Base64.encodeBase64(contents), bytesRead);
}