diff --git a/proposal/sandbox/filterreaders/src/main/org/apache/tools/ant/filters/TabsToSpaces.java b/proposal/sandbox/filterreaders/src/main/org/apache/tools/ant/filters/TabsToSpaces.java new file mode 100644 index 000000000..35e8c763d --- /dev/null +++ b/proposal/sandbox/filterreaders/src/main/org/apache/tools/ant/filters/TabsToSpaces.java @@ -0,0 +1,120 @@ +package org.apache.tools.ant.filters; + +import java.io.FilterReader; +import java.io.IOException; +import java.io.Reader; +import java.util.Hashtable; + +import org.apache.tools.ant.types.Parameter; +import org.apache.tools.ant.types.Parameterizable; + +/** + * Converts tabs to spaces. + * + * Example Usage: + * ============= + * + * + * + * + * @author Magesh Umasankar + */ +public final class TabsToSpaces + extends FilterReader + implements Parameterizable +{ + private static final int DEFAULT_TAB_LENGTH = 8; + + private static final String TAB_LENGTH_KEY = "tablength"; + + private Parameter[] parameters; + + private boolean initialized; + + private int tabLength = DEFAULT_TAB_LENGTH; + + private int spacesRemaining = 0; + + /** + * Create a new filtered reader. + * + * @param in a Reader object providing the underlying stream. + */ + public TabsToSpaces(final Reader in) { + super(in); + } + + /** + * Convert tabs with spaces + */ + public final int read() throws IOException { + if (!initialized) { + initialize(); + initialized = true; + } + + int ch = -1; + + if (spacesRemaining > 0) { + spacesRemaining--; + ch = ' '; + } else { + ch = in.read(); + if (ch == '\t') { + spacesRemaining = tabLength - 1; + ch = ' '; + } + } + return ch; + } + + public final int read(final char cbuf[], final int off, + final int len) throws IOException { + for (int i = 0; i < len; i++) { + final int ch = read(); + if (ch == -1) { + if (i == 0) { + return -1; + } else { + return i; + } + } + cbuf[off + i] = (char) ch; + } + return len; + } + + public final long skip(long n) throws IOException { + for (long i = 0; i < n; i++) { + if (in.read() == -1) { + return i; + } + } + return n; + } + + /** + * Set Parameters + */ + public final void setParameters(final Parameter[] parameters) { + this.parameters = parameters; + initialized = false; + } + + /** + * Initialize tokens and load the replacee-replacer hashtable. + */ + private final void initialize() { + if (parameters != null) { + for (int i = 0; i < parameters.length; i++) { + if (parameters[i] != null) { + if (TAB_LENGTH_KEY.equals(parameters[i].getName())) { + tabLength = + new Integer(parameters[i].getValue()).intValue(); + break; + } + } + } + } + } +}