From 1310bc258a1c3144e46744c85822403966489955 Mon Sep 17 00:00:00 2001
From: Havoc Pennington <hp@pobox.com>
Date: Tue, 28 Feb 2012 13:02:34 -0500
Subject: [PATCH] Add -Dconfig.trace=loads feature to log where config is
loaded from to stderr
---
.../com/typesafe/config/impl/ConfigImpl.java | 47 +++++++++++++++++++
.../com/typesafe/config/impl/Parseable.java | 24 ++++++++++
2 files changed, 71 insertions(+)
diff --git a/config/src/main/java/com/typesafe/config/impl/ConfigImpl.java b/config/src/main/java/com/typesafe/config/impl/ConfigImpl.java
index 73ddfdce..be5dd019 100644
--- a/config/src/main/java/com/typesafe/config/impl/ConfigImpl.java
+++ b/config/src/main/java/com/typesafe/config/impl/ConfigImpl.java
@@ -413,4 +413,51 @@ public class ConfigImpl {
throw ConfigImplUtil.extractInitializerError(e);
}
}
+
+ private static class DebugHolder {
+ private static String LOADS = "loads";
+
+ private static Map<String, Boolean> loadDiagnostics() {
+ Map<String, Boolean> result = new HashMap<String, Boolean>();
+ result.put(LOADS, false);
+
+ // People do -Dconfig.trace=foo,bar to enable tracing of different things
+ String s = System.getProperty("config.trace");
+ if (s == null) {
+ return result;
+ } else {
+ String[] keys = s.split(",");
+ for (String k : keys) {
+ if (k.equals(LOADS)) {
+ result.put(LOADS, true);
+ } else {
+ System.err.println("config.trace property contains unknown trace topic '"
+ + k + "'");
+ }
+ }
+ return result;
+ }
+ }
+
+ private static final Map<String, Boolean> diagnostics = loadDiagnostics();
+
+ private static final boolean traceLoadsEnabled = diagnostics.get(LOADS);
+
+ static boolean traceLoadsEnabled() {
+ return traceLoadsEnabled;
+ }
+ }
+
+ /** For use ONLY by library internals, DO NOT TOUCH not guaranteed ABI */
+ public static boolean traceLoadsEnabled() {
+ try {
+ return DebugHolder.traceLoadsEnabled();
+ } catch (ExceptionInInitializerError e) {
+ throw ConfigImplUtil.extractInitializerError(e);
+ }
+ }
+
+ public static void trace(String message) {
+ System.err.println(message);
+ }
}
diff --git a/config/src/main/java/com/typesafe/config/impl/Parseable.java b/config/src/main/java/com/typesafe/config/impl/Parseable.java
index 49386031..8295fdfa 100644
--- a/config/src/main/java/com/typesafe/config/impl/Parseable.java
+++ b/config/src/main/java/com/typesafe/config/impl/Parseable.java
@@ -87,6 +87,12 @@ public abstract class Parseable implements ConfigParseable {
// to support the "allow missing" feature.
protected abstract Reader reader() throws IOException;
+ protected static void trace(String message) {
+ if (ConfigImpl.traceLoadsEnabled()) {
+ ConfigImpl.trace(message);
+ }
+ }
+
ConfigSyntax guessSyntax() {
return null;
}
@@ -300,6 +306,8 @@ public abstract class Parseable implements ConfigParseable {
@Override
protected Reader reader() {
+ if (ConfigImpl.traceLoadsEnabled())
+ trace("Loading config from reader " + reader);
return reader;
}
@@ -314,6 +322,7 @@ public abstract class Parseable implements ConfigParseable {
* is complete.
*/
public static Parseable newReader(Reader reader, ConfigParseOptions options) {
+
return new ParseableReader(doNotClose(reader), options);
}
@@ -327,6 +336,8 @@ public abstract class Parseable implements ConfigParseable {
@Override
protected Reader reader() {
+ if (ConfigImpl.traceLoadsEnabled())
+ trace("Loading config from a String " + input);
return new StringReader(input);
}
@@ -350,6 +361,8 @@ public abstract class Parseable implements ConfigParseable {
@Override
protected Reader reader() throws IOException {
+ if (ConfigImpl.traceLoadsEnabled())
+ trace("Loading config from a URL: " + input.toExternalForm());
InputStream stream = input.openStream();
return readerFromStream(stream);
}
@@ -400,6 +413,8 @@ public abstract class Parseable implements ConfigParseable {
@Override
protected Reader reader() throws IOException {
+ if (ConfigImpl.traceLoadsEnabled())
+ trace("Loading config from a file: " + input);
InputStream stream = new FileInputStream(input);
return readerFromStream(stream);
}
@@ -472,12 +487,19 @@ public abstract class Parseable implements ConfigParseable {
ConfigParseOptions finalOptions) throws IOException {
Enumeration<URL> e = loader.getResources(resource);
if (!e.hasMoreElements()) {
+ if (ConfigImpl.traceLoadsEnabled())
+ trace("Loading config from class loader " + loader
+ + " but there were no resources called " + resource);
throw new IOException("resource not found on classpath: " + resource);
}
AbstractConfigObject merged = SimpleConfigObject.empty(origin);
while (e.hasMoreElements()) {
URL url = e.nextElement();
+ if (ConfigImpl.traceLoadsEnabled())
+ trace("Loading config from URL " + url.toExternalForm() + " from class loader "
+ + loader);
+
ConfigOrigin elementOrigin = ((SimpleConfigOrigin) origin).addURL(url);
AbstractConfigValue v;
@@ -611,6 +633,8 @@ public abstract class Parseable implements ConfigParseable {
@Override
protected AbstractConfigObject rawParseValue(ConfigOrigin origin,
ConfigParseOptions finalOptions) {
+ if (ConfigImpl.traceLoadsEnabled())
+ trace("Loading config from properties " + props);
return PropertiesParser.fromProperties(origin, props);
}