add misc methods to classpath

classpath/java/lang/Boolean.java

@@ -12,6 +12,10 @@ public final class Boolean {
     this.value = value;
   }
 
+  public Boolean(String s) {
+    this.value = "true".equals(s);
+  }
+
   public static Boolean valueOf(boolean value) {
     return (value ? Boolean.TRUE : Boolean.FALSE);
   }

classpath/java/lang/Integer.java

@@ -12,6 +12,10 @@ public final class Integer extends Number {
     this.value = value;
   }
 
+  public Integer(String s) {
+    this.value = parseInt(s);
+  }
+
   public static Integer valueOf(int value) {
     return new Integer(value);
   }

classpath/java/lang/Long.java

@@ -9,6 +9,10 @@ public final class Long extends Number {
     this.value = value;
   }
 
+  public Long(String s) {
+    this.value = parseLong(s);
+  }
+
   public static Long valueOf(long value) {
     return new Long(value);
   }

classpath/java/lang/reflect/Method.java

@@ -110,4 +110,14 @@ public class Method<T> extends AccessibleObject implements Member {
   public static native Object invoke(Method method, Object instance,
                                      Object ... arguments)
     throws InvocationTargetException, IllegalAccessException;
+
+  public Class getReturnType() {
+    for (int i = 0; i < spec.length - 1; ++i) {
+      if (spec[i] == ')') {
+        return Class.forCanonicalName
+          (new String(spec, i + 1, spec.length - i - 2, false));
+      }
+    }
+    throw new RuntimeException();
+  }
 }