Modifier and Type	Class and Description
public static interface	Template.ResourceOpener Used to resolve references to resources in the template, through `#parse` directives.

Modifier and Type	Field and Description
private final ImmutableMap<String, Macro>	macros Macros that are defined in this template (this exact VTL file).
private final MethodFinder	methodFinder Caches `Method` objects for public methods accessed through references.
private final Node	root

Access	Constructor and Description
pack-priv	Template(Node root, ImmutableMap<String, Macro> macros)

Method Summary

Modifier and Type	Method and Description
public String	Returns: the string result of evaluating the template. evaluate(Map<String, ?> a map where the keys are variable names and the values are the corresponding variable values. For example, if `"x"` maps to 23, then `$x` in the template will expand to 23. vars) Evaluate the given template with the given initial set of variables.
pack-priv ImmutableMap<String, Macro>	getMacros()
public static Template	Returns: an object representing the parsed template. parseFrom(Reader a Reader that will supply the text of the template. It will be closed on return from this method. The Reader will be buffered internally by this method (via `BufferedReader`), so the passed-in Reader doesn't need to perform its own buffering. reader) Parses a VTL template from the given `Reader`.
public static Template	Returns: an object representing the parsed template. parseFrom(String name of the resource. May be null. resourceName, Template.ResourceOpener used to open the initial resource and resources referenced by `#parse` directives in the template. resourceOpener) Parses a VTL template of the given name using the given `ResourceOpener`.
pack-priv static Template	parseFrom(String resourceName, Template.ResourceOpener resourceOpener, Map<String, Template> parseCache)
pack-priv void	render(EvaluationContext context, StringBuilder output)

Inherited from java.lang.Object:: clone equals finalize getClass hashCode notify notifyAll toString wait wait wait

Field Detail

macros back to summary

macros	back to summary
private final ImmutableMap<String, Macro> macros Macros that are defined in this template (this exact VTL file). If the template includes `#parse` directives, those might end up defining other macros when a `#parse` is evaluated. The `#parse` produces a separate `Template` object with its own `macros` map. When the root `Template` is evaluated, the `EvaluationContext` starts off with the macros here, and each `#parse` that is executed may add macros to the map in the `EvaluationContext`.

private final ImmutableMap<String, Macro> macros

Macros that are defined in this template (this exact VTL file). If the template includes #parse directives, those might end up defining other macros when a #parse is evaluated. The #parse produces a separate Template object with its own macros map. When the root Template is evaluated, the EvaluationContext starts off with the macros here, and each #parse that is executed may add macros to the map in the EvaluationContext.

methodFinder back to summary

methodFinder	back to summary
private final MethodFinder methodFinder Caches `Method` objects for public methods accessed through references. The first time we evaluate `$var.property` or `$var.method(...)` for a `$var` of a given class and for a given property or method signature, we'll store the resultant `Method` object. Every subsequent time we'll reuse that `Method`. The method lookup is quite slow so caching is useful. The main downside is that we may potentially hold on to `Method` objects that will never be used with this `Template` again. But in practice templates tend to be used repeatedly with the same classes.

private final MethodFinder methodFinder

Caches Method objects for public methods accessed through references. The first time we evaluate $var.property or $var.method(...) for a $var of a given class and for a given property or method signature, we'll store the resultant Method object. Every subsequent time we'll reuse that Method. The method lookup is quite slow so caching is useful. The main downside is that we may potentially hold on to Method objects that will never be used with this Template again. But in practice templates tend to be used repeatedly with the same classes.

root	back to summary
private final Node root

Constructor Detail

Template	back to summary
pack-priv Template(Node root, ImmutableMap<String, Macro> macros)

Method Detail

evaluate back to summary

evaluate	back to summary
public String evaluate(Map<String, ?> vars) Evaluate the given template with the given initial set of variables. Parameters vars:Map<String, ?> a map where the keys are variable names and the values are the corresponding variable values. For example, if `"x"` maps to 23, then `$x` in the template will expand to 23. Returns:String the string result of evaluating the template. Exceptions EvaluationException: if the evaluation failed, for example because of an undefined reference. If the template contains a `#parse` directive, there may be an exception such as `ParseException` or `IOException` when the nested template is read and parsed. That exception will then be the cause of an `EvaluationException`.

public String evaluate(Map<String, ?> vars)

Evaluate the given template with the given initial set of variables.

Parameters

vars:Map<String, ?>: a map where the keys are variable names and the values are the corresponding variable values. For example, if "x" maps to 23, then $x in the template will expand to 23.

Returns:String

the string result of evaluating the template.

Exceptions

EvaluationException:: if the evaluation failed, for example because of an undefined reference. If the template contains a #parse directive, there may be an exception such as ParseException or IOException when the nested template is read and parsed. That exception will then be the cause of an EvaluationException.

getMacros	back to summary
pack-priv ImmutableMap<String, Macro> getMacros()

parseFrom back to summary

parseFrom	back to summary
public static Template parseFrom(Reader reader) throws IOException Parses a VTL template from the given `Reader`. The template cannot reference other templates (for example with `#parse`). For that, use `parseFrom(String, ResourceOpener)`. Parameters reader:Reader a Reader that will supply the text of the template. It will be closed on return from this method. The Reader will be buffered internally by this method (via `BufferedReader`), so the passed-in Reader doesn't need to perform its own buffering. Returns:Template an object representing the parsed template. Exceptions IOException: if there is an exception reading from `reader`, or if the template references another template via `#parse`. ParseException: if the text of the template could not be parsed.

public static Template parseFrom(Reader reader) throws IOException

Parses a VTL template from the given Reader. The template cannot reference other templates (for example with #parse). For that, use parseFrom(String, ResourceOpener).

Parameters

reader:Reader: a Reader that will supply the text of the template. It will be closed on return from this method. The Reader will be buffered internally by this method (via BufferedReader), so the passed-in Reader doesn't need to perform its own buffering.

Returns:Template

an object representing the parsed template.

Exceptions

IOException:: if there is an exception reading from reader, or if the template references another template via #parse.
ParseException:: if the text of the template could not be parsed.

parseFrom back to summary

parseFrom	back to summary
public static Template parseFrom(String resourceName, Template.ResourceOpener resourceOpener) throws IOException Parses a VTL template of the given name using the given `ResourceOpener`. Parameters resourceName:String name of the resource. May be null. resourceOpener:Template.ResourceOpener used to open the initial resource and resources referenced by `#parse` directives in the template. Returns:Template an object representing the parsed template. Exceptions IOException: if there is an exception opening or reading from any resource. ParseException: if the text of the template could not be parsed.

public static Template parseFrom(String resourceName, Template.ResourceOpener resourceOpener) throws IOException

Parses a VTL template of the given name using the given ResourceOpener.

Parameters

resourceName:String: name of the resource. May be null.
resourceOpener:Template.ResourceOpener: used to open the initial resource and resources referenced by #parse directives in the template.

Returns:Template

an object representing the parsed template.

Exceptions

IOException:: if there is an exception opening or reading from any resource.
ParseException:: if the text of the template could not be parsed.

parseFrom	back to summary
pack-priv static Template parseFrom(String resourceName, Template.ResourceOpener resourceOpener, Map<String, Template> parseCache) throws IOException

render	back to summary
pack-priv void render(EvaluationContext context, StringBuilder output)

com.google.escapevelocity back to summary

public Interface Template.ResourceOpener

Annotations

@FunctionalInterface

Used to resolve references to resources in the template, through #parse directives.

Here is an example that opens nested templates as resources relative to the calling class:

ResourceOpener resourceOpener = resourceName -> {
    InputStream inputStream = getClass().getResource(resourceName);
    if (inputStream == null) {
      throw new IOException("Unknown resource: " + resourceName);
    }
    return new BufferedReader(new InputStreamReader(inputStream, StandardCharsets.UTF_8));
  };
  Template template = Template.parseFrom("foo.vm", resourceOpener);

Method Summary

Modifier and Type	Method and Description
public Reader	Returns: a `Reader` for the resource. openResource(String the name of the resource to be read. This can be null if `Template.parseFrom` is called with a null `resourceName`. resourceName) Returns a `Reader` that will be used to read the given resource, then closed.

Method Detail

openResource back to summary

openResource	back to summary
public Reader openResource(String resourceName) throws IOException Returns a `Reader` that will be used to read the given resource, then closed. The caller of this method will perform its own buffering (via `BufferedReader`), so the returned Reader doesn't need to be buffered. Parameters resourceName:String the name of the resource to be read. This can be null if `Template.parseFrom` is called with a null `resourceName`. Returns:Reader a `Reader` for the resource. Exceptions IOException: if the resource cannot be opened.

public Reader openResource(String resourceName) throws IOException

Returns a Reader that will be used to read the given resource, then closed. The caller of this method will perform its own buffering (via BufferedReader), so the returned Reader doesn't need to be buffered.

Parameters

resourceName:String: the name of the resource to be read. This can be null if Template.parseFrom is called with a null resourceName.

Returns:Reader

a Reader for the resource.

Exceptions

IOException:: if the resource cannot be opened.

public Class Template

Nested and Inner Type Summary

Field Summary

Constructor Summary

Method Summary

Field Detail

Constructor Detail

Method Detail

public Interface Template.ResourceOpener

Method Summary

Method Detail