com.google.gwt.dev.jjs.impl

Class JsFunctionClusterer

java.lang.Object

com.google.gwt.dev.jjs.impl.JsAbstractTextTransformer

com.google.gwt.dev.jjs.impl.JsFunctionClusterer

public class JsFunctionClusterer
extends JsAbstractTextTransformer

Re-orders function declarations according to a given metric and clustering algorithm in order to boost gzip/deflation compression efficiency. This version uses the edit-distance algorithm as a metric, and a semi-greedy strategy for grouping functions together.

Field Summary

Fields inherited from class com.google.gwt.dev.jjs.impl.JsAbstractTextTransformer

js, originalStatementRanges, sourceInfoMap, statementRanges

Constructor Summary

Constructors

Constructor and Description
JsFunctionClusterer(JsAbstractTextTransformer xformer)
JsFunctionClusterer(String js, StatementRanges statementRanges, Map<Range,SourceInfo> sourceInfoMap)

Method Summary

Modifier and Type	Method and Description
protected void	endStatements(StringBuilder newJs, ArrayList<Integer> starts, ArrayList<Integer> ends) Called if any operations need to be performed after all statements have been processed.
void	exec()
int[]	getReorderedIndices() Returns the array of reordered statement indices after clustering.
protected void	updateSourceInfoMap() Fixes the index ranges of individual expressions in the generated JS after function clustering has reordered statements.

Methods inherited from class com.google.gwt.dev.jjs.impl.JsAbstractTextTransformer

addStatement, beginStatement, beginStatements, endStatement, getJs, getJsForRange, getSourceInfoMap, getStatementRanges, recomputeJsAndStatementRanges

Methods inherited from class java.lang.Object

equals, finalize, getClass, hashCode, toString

Constructor Detail

JsFunctionClusterer

public JsFunctionClusterer(JsAbstractTextTransformer xformer)

JsFunctionClusterer

public JsFunctionClusterer(String js,
                           StatementRanges statementRanges,
                           Map<Range,SourceInfo> sourceInfoMap)

Method Detail

exec

public void exec()

Specified by:

exec in class JsAbstractTextTransformer

getReorderedIndices

public int[] getReorderedIndices()

Returns the array of reordered statement indices after clustering.

Returns:

The array of indices, where the element at index j represents the index of the statement in the original code that is moved to index j in the new code after clustering.

endStatements

protected void endStatements(StringBuilder newJs,
                             ArrayList<Integer> starts,
                             ArrayList<Integer> ends)

Description copied from class: JsAbstractTextTransformer

Called if any operations need to be performed after all statements have been processed.

Overrides:

endStatements in class JsAbstractTextTransformer

updateSourceInfoMap

protected void updateSourceInfoMap()

Fixes the index ranges of individual expressions in the generated JS after function clustering has reordered statements. Loops over each expression, determines which statement it falls in, and shifts the indices according to where that statement moved.

Specified by:

updateSourceInfoMap in class JsAbstractTextTransformer