quick sketch of java/io/*

classpath/java/io/BufferedInputStream.java

@@ -0,0 +1,68 @@
+package java.io;
+
+public class BufferedInputStream extends InputStream {
+  private final InputStream in;
+  private final byte[] buffer;
+  private int position;
+  private int limit;
+
+  public BufferedInputStream(InputStream in, int size) {
+    this.in = in;
+    this.buffer = new byte[size];
+  }
+  
+  public BufferedInputStream(InputStream in) {
+    this(in, 32);
+  }
+
+  private void fill() throws IOException {
+    position = 0;
+    limit = in.read(buffer);
+  }
+
+  public int read() throws IOException {
+    if (position >= limit) {
+      fill();
+      if (limit == -1) {
+        return -1;
+      }
+    }
+
+    return buffer[position++];
+  }
+
+  public int read(byte[] b, int offset, int length) throws IOException {
+    int count = 0;
+
+    if (position < limit) {
+      int remaining = limit - position;
+      if (remaining > length) {
+        remaining = length;
+      }
+
+      System.arraycopy(buffer, position, b, offset, remaining);
+
+      count += remaining;
+      position += remaining;
+      offset += remaining;
+      length -= remaining;
+    }
+
+    if (length > 0) {
+      int c = in.read(b, offset, length);
+      if (c == -1) {
+        if (count == 0) {
+          count = -1;
+        }
+      } else {
+        count += c;
+      }
+    }
+
+    return count;
+  }
+
+  public void close() throws IOException {
+    in.close();
+  }
+}

classpath/java/io/BufferedOutputStream.java

@@ -0,0 +1,51 @@
+package java.io;
+
+public class BufferedOutputStream extends OutputStream {
+  private final OutputStream out;
+  private final byte[] buffer;
+  private int position;
+
+  public BufferedOutputStream(OutputStream out, int size) {
+    this.out = out;
+    this.buffer = new byte[size];
+  }
+  
+  public BufferedOutputStream(OutputStream out) {
+    this(out, 4096);
+  }
+  
+  private void drain() throws IOException {
+    if (position > 0) {
+      out.write(buffer, 0, position);
+      position = 0;
+    }
+  }
+
+  public void write(int c) throws IOException {
+    if (position >= buffer.length) {
+      drain();
+    }
+
+    buffer[position++] = (byte) (c & 0xFF);
+  }
+
+  public void write(byte[] b, int offset, int length) throws IOException {
+    if (length > buffer.length - position) {
+      drain();
+      out.write(b, offset, length);      
+    } else {
+      System.arraycopy(b, offset, buffer, position, length);
+      position += length;
+    }
+  }
+
+  public void flush() throws IOException {
+    drain();
+    out.flush();
+  }
+
+  public void close() throws IOException {
+    flush();
+    out.close();
+  }
+}

classpath/java/io/FileDescriptor.java

@@ -0,0 +1,17 @@
+package java.io;
+
+public class FileDescriptor {
+  public static final FileDescriptor in = new FileDescriptor(0);
+  public static final FileDescriptor out = new FileDescriptor(1);
+  public static final FileDescriptor err = new FileDescriptor(2);
+
+  private final int value;
+
+  private FileDescriptor(int value) {
+    this.value = value;
+  }
+
+  public FileDescriptor() {
+    this(-1);
+  }
+}

classpath/java/io/FileInputStream.java

@@ -0,0 +1,15 @@
+package java.io;
+
+public class FileInputStream extends InputStream {
+  private final FileDescriptor fd;
+
+  public FileInputStream(FileDescriptor fd) {
+    this.fd = fd;
+  }
+
+  public native int read() throws IOException;
+
+  public native int read(byte[] b, int offset, int length) throws IOException;
+
+  public native void close() throws IOException;
+}

classpath/java/io/FileOutputStream.java

@@ -0,0 +1,16 @@
+package java.io;
+
+public class FileOutputStream extends OutputStream {
+  private final FileDescriptor fd;
+
+  public FileOutputStream(FileDescriptor fd) {
+    this.fd = fd;
+  }
+
+  public native void write(int c) throws IOException;
+
+  public native void write(byte[] b, int offset, int length)
+    throws IOException;
+
+  public native void close() throws IOException;
+}

classpath/java/io/IOException.java

@@ -0,0 +1,19 @@
+package java.io;
+
+public class IOException extends Exception {
+  public IOException(String message, Throwable cause) {
+    super(message, cause);
+  }
+
+  public IOException(String message) {
+    this(message, null);
+  }
+
+  public IOException(Throwable cause) {
+    this(null, cause);
+  }
+
+  public IOException() {
+    this(null, null);
+  }
+}

classpath/java/io/InputStream.java

@@ -0,0 +1,27 @@
+package java.io;
+
+public abstract class InputStream {
+  public abstract int read() throws IOException;
+
+  public int read(byte[] buffer) throws IOException {
+    return read(buffer, 0, buffer.length);
+  }
+
+  public int read(byte[] buffer, int offset, int length) throws IOException {
+    for (int i = 0; i < length; ++i) {
+      int c = read();
+      if (c == -1) {
+        if (i == 0) {
+          return -1;
+        } else {
+          return i;
+        }
+      } else {
+        buffer[offset + i] = (byte) (c & 0xFF);
+      }
+    }
+    return length;
+  }
+
+  public void close() throws IOException { }
+}

classpath/java/io/OutputStream.java

@@ -0,0 +1,19 @@
+package java.io;
+
+public abstract class OutputStream {
+  public abstract void write(int c) throws IOException;
+
+  public void write(byte[] buffer) throws IOException {
+    write(buffer, 0, buffer.length);
+  }
+
+  public void write(byte[] buffer, int offset, int length) throws IOException {
+    for (int i = 0; i < length; ++i) {
+      write(buffer[offset + i]);
+    }
+  }
+
+  public void flush() throws IOException { }
+
+  public void close() throws IOException { }
+}

classpath/java/io/PrintStream.java

@@ -0,0 +1,51 @@
+package java.io;
+
+public class PrintStream extends OutputStream {
+  private static final byte[] newline
+    = System.getProperty("line.separator").getBytes();
+
+  private final OutputStream out;
+  private final boolean autoFlush;
+
+  public PrintStream(OutputStream out, boolean autoFlush) {
+    this.out = out;
+    this.autoFlush = true;
+  }
+
+  public PrintStream(OutputStream out) {
+    this(out, false);
+  }
+
+  public synchronized void print(String s) {
+    try {
+      out.write(s.getBytes());
+      if (autoFlush) flush();
+    } catch (IOException e) { }
+  }
+
+  public synchronized void println(String s) {
+    try {
+      out.write(s.getBytes());    
+      out.write(newline);
+      if (autoFlush) flush();
+    } catch (IOException e) { }
+  }
+  
+  public void write(int c) throws IOException {
+    out.write(c);
+    if (autoFlush && c == '\n') flush();
+  }
+
+  public void write(byte[] buffer, int offset, int length) throws IOException {
+    out.write(buffer, offset, length);
+    if (autoFlush) flush();
+  }
+
+  public void flush() throws IOException {
+    out.flush();
+  }
+
+  public void close() throws IOException {
+    out.close();
+  }
+}

classpath/java/lang/String.java

@@ -130,6 +130,30 @@ public final class String implements Comparable<String> {
     }
   }
 
+  public byte[] getBytes() {
+    byte[] b = new byte[length];
+    getBytes(0, length, b, 0);
+    return b;
+  }
+
+  public void getBytes(int srcOffset, int srcLength,
+                       byte[] dst, int dstOffset)
+  {
+    if (srcOffset + srcLength > length) {
+      throw new IndexOutOfBoundsException();
+    }
+
+    if (data instanceof char[]) {
+      char[] src = (char[]) data;
+      for (int i = 0; i < srcLength; ++i) {
+        dst[i + dstOffset] = (byte) src[i + offset + srcOffset];
+      }
+    } else {
+      byte[] src = (byte[]) data;
+      System.arraycopy(src, offset + srcOffset, dst, dstOffset, srcLength);
+    }
+  }
+
   public void getChars(int srcOffset, int srcLength,
                        char[] dst, int dstOffset)
   {

classpath/java/lang/System.cpp

@@ -5,17 +5,6 @@
 #undef JNIEXPORT
 #define JNIEXPORT __attribute__ ((visibility("default")))
 
-extern "C" JNIEXPORT void JNICALL
-Java_java_lang_System_00024Output_print(JNIEnv* e, jobject, jstring s)
-{
-  jboolean isCopy;
-  const char* chars = e->GetStringUTFChars(s, &isCopy);
-  if (chars) {
-    printf("%s", chars);
-  }
-  e->ReleaseStringUTFChars(s, chars);
-}
-
 extern "C" JNIEXPORT jstring JNICALL
 Java_java_lang_System_getProperty(JNIEnv* e, jstring key)
 {

classpath/java/lang/System.java

@@ -1,13 +1,27 @@
 package java.lang;
 
-public abstract class System {
-  public static final Output out = new Output();
-  public static final Output err = out;
+import java.io.PrintStream;
+import java.io.InputStream;
+import java.io.BufferedInputStream;
+import java.io.BufferedOutputStream;
+import java.io.FileInputStream;
+import java.io.FileOutputStream;
+import java.io.FileDescriptor;
 
+public abstract class System {
   static {
     loadLibrary("natives");
   }
 
+  public static final PrintStream out = new PrintStream
+    (new BufferedOutputStream(new FileOutputStream(FileDescriptor.out)), true);
+
+  public static final PrintStream err = new PrintStream
+    (new BufferedOutputStream(new FileOutputStream(FileDescriptor.err)), true);
+
+  public static final InputStream in
+    = new BufferedInputStream(new FileInputStream(FileDescriptor.in));
+
   public static native void arraycopy(Object src, int srcOffset, Object dst,
                                       int dstOffset, int length);
 
@@ -26,13 +40,4 @@ public abstract class System {
   public static void exit(int code) {
     Runtime.getRuntime().exit(code);
   }
-
-  public static class Output {
-    public synchronized native void print(String s);
-
-    public synchronized void println(String s) {
-      print(s);
-      print(getProperty("line.separator"));
-    }
-  }
 }

makefile

@@ -16,7 +16,7 @@ src = src
 classpath = classpath
 test = test
 
-input = $(cls)/Threads.class
+input = $(cls)/Hello.class
 
 cxx = g++
 cc = gcc

src/machine.h

@@ -22,7 +22,7 @@
 namespace vm {
 
 const bool Verbose = false;
-const bool DebugRun = false;
+const bool DebugRun = true;
 const bool DebugStack = false;
 const bool DebugMonitors = false;
 

test/Reflection.java

@@ -5,7 +5,7 @@ public class Reflection {
   public static void main(String[] args) throws Exception {
     Class system = Class.forName("java.lang.System");
     Field out = system.getDeclaredField("out");
-    Class output = Class.forName("java.lang.System$Output");
+    Class output = Class.forName("java.io.PrintStream");
     Method println = output.getDeclaredMethod("println", String.class);
 
     println.invoke(out.get(null), "Hello, World!");