altoslib: Create data file open helper in AltosLib

Use InputStream everywhere, instead of Reader.
Create private string input stream as java one is deprecated.

Signed-off-by: Keith Packard <keithp@keithp.com>

1 files changed, 61 insertions, 0 deletions

diff --git a/altoslib/AltosStringInputStream.java b/altoslib/AltosStringInputStream.java
new file mode 100644
index 00000000..d574db24
--- /dev/null
+++ b/altoslib/AltosStringInputStream.java
@@ -0,0 +1,61 @@
+/*
+ * Copyright © 2017 Keith Packard <keithp@keithp.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ */
+
+package org.altusmetrum.altoslib_11;
+
+import java.util.*;
+import java.io.*;
+
+public class AltosStringInputStream extends InputStream {
+
+	String	s;
+	int	at;
+	int	mark;
+
+	public int available() {
+		return s.length() - at;
+	}
+
+	public void mark(int read_limit) {
+		mark = at;
+	}
+
+	public boolean markSupported() {
+		return true;
+	}
+
+	public int read() {
+		if (at == s.length())
+			return -1;
+		return (int) s.charAt(at++);
+	}
+
+	public void reset() {
+		at = mark;
+	}
+
+	public long skip(long n) throws IOException {
+		if (n < 0) n = 0;
+
+		if (at + n > s.length())
+			n = s.length() - at;
+		at += n;
+		return n;
+	}
+
+	public AltosStringInputStream(String s) {
+		this.s = s;
+		this.at = 0;
+	}
+}