com.fastchar.multipart.LimitedServletInputStream Maven / Gradle / Ivy

package com.fastchar.multipart;

import javax.servlet.ServletInputStream;
import java.io.IOException;
/**
 * from com.oreilly.servlet.multipart
 */
public class LimitedServletInputStream extends ServletInputStream {
    private ServletInputStream in;
    private int totalExpected;
    private int totalRead = 0;

    public LimitedServletInputStream(ServletInputStream in, int totalExpected) {
        this.in = in;
        this.totalExpected = totalExpected;
    }

    public int readLine(byte[] b, int off, int len) throws IOException {
        int left = this.totalExpected - this.totalRead;
        if (left <= 0) {
            return -1;
        } else {
            int result = this.in.readLine(b, off, Math.min(left, len));
            if (result > 0) {
                this.totalRead += result;
            }

            return result;
        }
    }

    public int read() throws IOException {
        if (this.totalRead >= this.totalExpected) {
            return -1;
        } else {
            int result = this.in.read();
            if (result != -1) {
                ++this.totalRead;
            }

            return result;
        }
    }

    public int read(byte[] b, int off, int len) throws IOException {
        int left = this.totalExpected - this.totalRead;
        if (left <= 0) {
            return -1;
        } else {
            int result = this.in.read(b, off, Math.min(left, len));
            if (result > 0) {
                this.totalRead += result;
            }

            return result;
        }
    }


}