本文整理了Java中org.apache.tools.ant.Project.getReference()方法的一些代码示例，展示了Project.getReference()的具体用法。这些代码示例主要来源于Github/Stackoverflow/Maven等平台，是从一些精选项目中提取出来的代码，具有较强的参考意义，能在一定程度帮忙到你。Project.getReference()方法的具体详情如下：
包路径：org.apache.tools.ant.Project
类名称：Project
方法名：getReference

Project.getReference介绍

[英]Look up a reference by its key (ID).
[中]通过其键（ID）查找引用。

代码示例

代码示例来源：origin: org.apache.ant/ant

/**
 * Resolve the reference, using the associated project if
 * it set, otherwise use the passed in project.
 * @param fallback the fallback project to use if the project attribute of
 *                 reference is not set.
 * @return the dereferenced object.
 * @throws BuildException if the reference cannot be dereferenced.
 */
public Object getReferencedObject(Project fallback) throws BuildException {
  if (refid == null) {
    throw new BuildException("No reference specified");
  }
  Object o = project == null ? fallback.getReference(refid) : project.getReference(refid);
  if (o == null) {
    throw new BuildException("Reference " + refid + " not found.");
  }
  return o;
}

代码示例来源：origin: org.apache.ant/ant

private PropertyHelper.Delegate resolve() {
    if (refid == null) {
      throw new BuildException("refid required for generic delegate");
    }
    return (PropertyHelper.Delegate) getProject().getReference(refid);
  }
}

代码示例来源：origin: org.apache.ant/ant

private static CommandLauncher extractLauncher(String referenceName,
                        Project project) {
  return Optional.ofNullable(project)
    .map(p -> p.<CommandLauncher> getReference(referenceName))
    .orElseGet(() -> getSystemLauncher(referenceName));
}

代码示例来源：origin: org.apache.ant/ant

public Object evaluate(String property, PropertyHelper propertyHelper) {
    Object o = null;
    if (property.startsWith(PREFIX) && propertyHelper.getProject() != null) {
      o = propertyHelper.getProject().getReference(property.substring(PREFIX_LEN));
    }
    return o == null ? null : o.toString();
  }
};

代码示例来源：origin: org.apache.ant/ant

/**
 * Return the descriptions from all the targets of
 * a project.
 *
 * @param project the project to get the descriptions for.
 * @return a string containing the concatenated descriptions of
 *         the targets.
 */
public static String getDescription(Project project) {
  List<Target> targets = project.getReference(ProjectHelper2.REFID_TARGETS);
  if (targets == null) {
    return null;
  }
  StringBuilder description = new StringBuilder();
  for (Target t : targets) {
    concatDescriptions(project, t, description);
  }
  return description.toString();
}

代码示例来源：origin: org.apache.ant/ant

public Object evaluate(String prop, PropertyHelper helper) {
    return prop.startsWith(PREFIX) && helper.getProject() != null
      ? helper.getProject().getReference(prop.substring(PREFIX_LEN))
      : null;
  }
};

代码示例来源：origin: org.apache.ant/ant

private ScriptDef getScript() {
  String name = getTaskType();
  Map<String, ScriptDef> scriptRepository =
    getProject().getReference(MagicNames.SCRIPT_REPOSITORY);
  if (scriptRepository == null) {
    throw new BuildException("Script repository not found for " + name);
  }
  ScriptDef definition = scriptRepository.get(getTaskType());
  if (definition == null) {
    throw new BuildException("Script definition not found for " + name);
  }
  return definition;
}

代码示例来源：origin: org.apache.ant/ant

/**
 * Finds or creates the script repository - it is stored in the project.
 * This method is synchronized on the project under {@link MagicNames#SCRIPT_REPOSITORY}
 * @return the current script repository registered as a reference.
 */
private Map<String, ScriptDef> lookupScriptRepository() {
  Map<String, ScriptDef> scriptRepository;
  Project p = getProject();
  synchronized (p) {
    scriptRepository =
        p.getReference(MagicNames.SCRIPT_REPOSITORY);
    if (scriptRepository == null) {
      scriptRepository = new HashMap<>();
      p.addReference(MagicNames.SCRIPT_REPOSITORY,
          scriptRepository);
    }
  }
  return scriptRepository;
}

代码示例来源：origin: org.apache.ant/ant

/**
 * Convenience overloaded version of {@link #getClassLoaderForPath(Project, Path,
 * String, boolean)}.
 *
 * <p>Delegates to the other one after extracting the referenced
 * Path from the Project. This checks also that the passed
 * Reference is pointing to a Path all right.</p>
 * @param p current Ant project
 * @param ref Reference to Path structure
 * @param reverseLoader if set to true this new loader will take
 * precedence over its parent (which is contra the regular
 * classloader behaviour)
 * @return The class loader
 */
public static ClassLoader getClassLoaderForPath(
  Project p, Reference ref, boolean reverseLoader) {
  String pathId = ref.getRefId();
  Object path = p.getReference(pathId);
  if (!(path instanceof Path)) {
    throw new BuildException(
      "The specified classpathref %s does not reference a Path.",
      pathId);
  }
  String loaderId = MagicNames.REFID_CLASSPATH_LOADER_PREFIX + pathId;
  return getClassLoaderForPath(p, (Path) path, loaderId, reverseLoader);
}

代码示例来源：origin: org.apache.ant/ant

/**
 * Get a property. If all hooks return null, the default
 * tables will be used.
 *
 * <p>As of Ant 1.8.0 this method is never invoked by any code
 * inside of Ant itself.</p>
 *
 * @param ns namespace of the sought property.
 * @param name name of the sought property.
 * @param user True if this is a user property.
 * @return The property, if returned by a hook, or null if none.
 * @deprecated PropertyHelper chaining is deprecated.
 */
@Deprecated
public Object getPropertyHook(String ns, String name, boolean user) {
  if (getNext() != null) {
    Object o = getNext().getPropertyHook(ns, name, user);
    if (o != null) {
      return o;
    }
  }
  // Experimental/Testing, will be removed
  if (project != null && name.startsWith("toString:")) {
    name = name.substring("toString:".length());
    Object v = project.getReference(name);
    return (v == null) ? null : v.toString();
  }
  return null;
}

代码示例来源：origin: org.apache.ant/ant

/**
 * Return the value for the given attribute.
 * If we are not using semantic attributes, its just the
 * literal string value of the attribute.
 *
 * <p>If we <em>are</em> using semantic attributes, then first
 * dependent properties are resolved (i.e., ${foo} is resolved
 * based on the foo property value), and then an appropriate data
 * type is used.  In particular, location-based properties are
 * resolved to absolute file names.  Also for refid values, look
 * up the referenced object from the project.</p>
 */
private String getAttributeValue(Node attributeNode) {
  String nodeValue = attributeNode.getNodeValue().trim();
  if (semanticAttributes) {
    String attributeName = attributeNode.getNodeName();
    nodeValue = getProject().replaceProperties(nodeValue);
    if (LOCATION.equals(attributeName)) {
      File f = resolveFile(nodeValue);
      return f.getPath();
    }
    if (REF_ID.equals(attributeName)) {
      Object ref = getProject().getReference(nodeValue);
      if (ref != null) {
        return ref.toString();
      }
    }
  }
  return nodeValue;
}

代码示例来源：origin: org.apache.ant/ant

private void resolveRefid() {
  try {
    if (getProject() == null) {
      throw new BuildException("Cannot retrieve refid; project unset");
    }
    Object o = getProject().getReference(refid);
    if (!(o instanceof Resource)) {
      if (o instanceof ResourceCollection) {
        ResourceCollection rc = (ResourceCollection) o;
        if (rc.size() == 1) {
          o = rc.iterator().next();
        }
      } else {
        throw new BuildException("Illegal value at '%s': %s", refid, o);
      }
    }
    this.resource = (Resource) o;
  } finally {
    refid = null;
  }
}

代码示例来源：origin: org.apache.ant/ant

private InputHandler getInputHandler() {
    if (type != null) {
      return type.getInputHandler();
    }
    if (refid != null) {
      try {
        return (InputHandler) (getProject().getReference(refid));
      } catch (final ClassCastException e) {
        throw new BuildException(
          refid + " does not denote an InputHandler", e);
      }
    }
    if (classname != null) {
      return ClasspathUtils.newInstance(classname,
        createLoader(), InputHandler.class);
    }
    throw new BuildException(
      "Must specify refid, classname or type");
  }
}

代码示例来源：origin: org.apache.ant/ant

@Override
  public void execute() throws BuildException {
    if (extensionPoint == null) {
      throw new BuildException("extensionPoint required", getLocation());
    }

    if (getOwningTarget() == null
        || !getOwningTarget().getName().isEmpty()) {
      throw new BuildException("bindtargets only allowed as a top-level task");
    }

    if (onMissingExtensionPoint == null) {
      onMissingExtensionPoint = OnMissingExtensionPoint.FAIL;
    }
    final ProjectHelper helper = getProject().getReference(
        ProjectHelper.PROJECTHELPER_REFERENCE);

    for (String target : targets) {
      helper.getExtensionStack().add(new String[] {extensionPoint,
        target, onMissingExtensionPoint.name()});
    }
  }
}

代码示例来源：origin: org.apache.ant/ant

/**
 * {@inheritDoc}
 */
public synchronized Object getProxy() {
  if (getProject() == null) {
    throw new IllegalStateException(getTaskName() + "Project owner unset");
  }
  hijackId();
  if (getProject().hasReference(id)) {
    Object result = getProject().getReference(id);
    log("project reference " + id + "=" + String.valueOf(result), Project.MSG_DEBUG);
    return result;
  }
  throw new IllegalStateException("Unknown reference \"" + id + "\"");
}

代码示例来源：origin: org.apache.ant/ant

/**
 * Find a project component for a specific project, creating
 * it if it does not exist.
 * @param project the project.
 * @return the project component for a specific project.
 */
public static ComponentHelper getComponentHelper(Project project) {
  if (project == null) {
    return null;
  }
  // Singleton for now, it may change (per/classloader)
  ComponentHelper ph = project.getReference(COMPONENT_HELPER_REFERENCE);
  if (ph != null) {
    return ph;
  }
  ph = new ComponentHelper();
  ph.setProject(project);
  project.addReference(COMPONENT_HELPER_REFERENCE, ph);
  return ph;
}

代码示例来源：origin: org.apache.ant/ant

/**
 * @return true if the reference exists and if type is set, if
 *              the reference is the same type
 * @exception BuildException if an error occurs
 */
@Override
public boolean eval() throws BuildException {
  if (ref == null) {
    throw new BuildException(
        "No reference specified for isreference condition");
  }
  String key = ref.getRefId();
  if (!getProject().hasReference(key)) {
    return false;
  }
  if (type == null) {
    return true;
  }
  Class<?> typeClass = getProject().getDataTypeDefinitions().get(type);
  if (typeClass == null) {
    typeClass = getProject().getTaskDefinitions().get(type);
  }
  // if the type is unknown, throw exception instead?
  return typeClass != null
      && typeClass.isAssignableFrom(getProject().getReference(key).getClass());
}

代码示例来源：origin: org.apache.ant/ant

/**
 * Factory method to create a property processor.
 * Users can provide their own or replace it using "ant.PropertyHelper"
 * reference. User tasks can also add themselves to the chain, and provide
 * dynamic properties.
 *
 * @param project the project for which the property helper is required.
 *
 * @return the project's property helper.
 */
public static synchronized PropertyHelper getPropertyHelper(Project project) {
  PropertyHelper helper = null;
  if (project != null) {
    helper = project.getReference(MagicNames.REFID_PROPERTY_HELPER);
  }
  if (helper != null) {
    return helper;
  }
  helper = new PropertyHelper();
  helper.setProject(project);
  if (project != null) {
    project.addReference(MagicNames.REFID_PROPERTY_HELPER, helper);
  }
  return helper;
}

代码示例来源：origin: org.apache.ant/ant

/**
 * Get a localproperties for the given project.
 * @param project the project to retrieve the localproperties for.
 * @return the localproperties.
 */
public static synchronized LocalProperties get(Project project) {
  LocalProperties l =
    project.getReference(MagicNames.REFID_LOCAL_PROPERTIES);
  if (l == null) {
    l = new LocalProperties();
    project.addReference(MagicNames.REFID_LOCAL_PROPERTIES, l);
    PropertyHelper.getPropertyHelper(project).add(l);
  }
  return l;
}

代码示例来源：origin: org.apache.ant/ant

/**
 * Adds descriptive text to the project.
 *
 * @param text the descriptive text
 */
public void addText(String text) {
  ProjectHelper ph = getProject().getReference(ProjectHelper.PROJECTHELPER_REFERENCE);
  if (!(ph instanceof ProjectHelperImpl)) {
    // New behavior for delayed task creation. Description
    // will be evaluated in Project.getDescription()
    return;
  }
  String currentDescription = getProject().getDescription();
  if (currentDescription == null) {
    getProject().setDescription(text);
  } else {
    getProject().setDescription(currentDescription + text);
  }
}