1 files changed, 91 insertions, 0 deletions
diff --git a/src/main/java/com/google/devtools/build/lib/rules/java/GenericBuildInfoPropertiesTranslator.java b/src/main/java/com/google/devtools/build/lib/rules/java/GenericBuildInfoPropertiesTranslator.java
new file mode 100644
index 0000000000..df6a325437
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/rules/java/GenericBuildInfoPropertiesTranslator.java
@@ -0,0 +1,91 @@
+// Copyright 2014 Google Inc. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+package com.google.devtools.build.lib.rules.java;
+
+import com.google.devtools.build.lib.util.Fingerprint;
+
+import java.util.Map;
+import java.util.Properties;
+
+/** The generic implementation of {@link BuildInfoPropertiesTranslator} */
+public class GenericBuildInfoPropertiesTranslator implements
+    BuildInfoPropertiesTranslator {
+
+  private static final String GUID = "e71fe4a8-11af-4ec0-9b38-1d3e7f542f51";
+
+  // syntax is %ID% for a property that depends on the ID key, %ID|default% to
+  // always add the property with the "default" key, %% is to add a percent sign
+  private final Map<String, String> translationKeys;
+  
+  /**
+   * Create a generic translator, for each key,value pair in {@code translationKeys}, the key
+   * represents the property key that will be written and the value, its value. Inside value every
+   * %ID% is replaced by the corresponding build information with the same ID key. The property
+   * won't be added if it's depends on an unresolved build information. Adding a property can
+   * be forced even if a build information is missing by specifying a default value using the
+   * %ID|default% syntax. Finally to add a percent sign, just use the %% syntax.
+   */
+  public GenericBuildInfoPropertiesTranslator(Map<String, String> translationKeys) {
+    this.translationKeys = translationKeys;
+  }
+
+  @Override
+  public String computeKey() {
+    Fingerprint f = new Fingerprint();
+    f.addString(GUID);
+    f.addStringMap(translationKeys);
+    return f.hexDigestAndReset();
+  }
+
+  @Override
+  public void translate(Map<String, String> buildInfo, Properties properties) {
+    for (Map.Entry<String, String> entry : translationKeys.entrySet()) {
+      String translatedValue = translateValue(entry.getValue(), buildInfo);
+      if (translatedValue != null) {
+        properties.put(entry.getKey(), translatedValue);
+      }
+    }
+  }
+
+  private String translateValue(String valueDescription, Map<String, String> buildInfo) {
+    String[] split = valueDescription.split("%");
+    StringBuffer result = new StringBuffer();
+    boolean isInsideKey = false;
+    for (String key : split) {
+      if (isInsideKey) {
+        if (key.isEmpty()) {
+          result.append("%"); // empty key means %%
+        } else {
+          String defaultValue = null;
+          int i = key.lastIndexOf('|');
+          if (i >= 0) {
+            defaultValue = key.substring(i + 1);
+            key = key.substring(0, i);
+          }
+          if (buildInfo.containsKey(key)) {
+            result.append(buildInfo.get(key));
+          } else if (defaultValue != null) {
+            result.append(defaultValue);
+          } else { // we haven't found the requested key so we ignore the whole value
+            return null;
+          }
+        }
+      } else {
+        result.append(key);
+      }
+      isInsideKey = !isInsideKey;
+    }
+    return result.toString();
+  }
+}