Bug 97918 [formatter] tab policy and indentation policy: indent on column
I would like a smarter tab policy. In code formated like this: class Example { Example(int arg1, int arg2, int arg3, int arg4, int arg5, int arg6) { this(); } Example() { } } I would like to have a mix of tabs and spaces like this: class Example { <tb>Example(int arg1, int arg2, <tb> int arg3, int arg4, <tb> int arg5, int arg6) { <tb><tb>this(); <tb>} <tb>Example() { <tb>} } If the code it is formated like this then it looks good whether a editor is using 4 or 8 space tabs. I called this a smarter tab policy because it means the code that implements the tab policy needs to know more than just a column number. It needs an indentation level and column offset. This could be configured by setting the tab policy to "mixed" and then have a check box that says "use spaces for column alignment" Or it could be configured by a new tab policy called "portable mixed", and in that case only the tab size field is needed. On another note it is bad that the Constructor Declarations->parameters example in the code formatting dialog uses the word "Example" which happens to be 8 chars. So in "tab only" tab policy with tabs of 2,4, or 8, the example doesn't show what will happen when "indent on column" is set. The method declarations->parameters example makes this clear.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/preferences/formatter/IndentationTabPage.java
tabPreference.setKey(DefaultCodeFormatterConstants.FORMATTER_TAB_SIZE);
			indentPreference.setEnabled(true);
			indentPreference.setKey(DefaultCodeFormatterConstants.FORMATTER_INDENTATION_SIZE);
		} else if (JavaCore.SPACE.equals(tabPolicy)) {
			if (DefaultCodeFormatterConstants.MIXED.equals(fOldTabChar))
				swapTabValues();
			tabPreference.setEnabled(true);
			tabPreference.setKey(DefaultCodeFormatterConstants.FORMATTER_INDENTATION_SIZE);
			indentPreference.setEnabled(true);
			indentPreference.setKey(DefaultCodeFormatterConstants.FORMATTER_TAB_SIZE);
		} else if (JavaCore.TAB.equals(tabPolicy)) {
			if (DefaultCodeFormatterConstants.MIXED.equals(fOldTabChar))
				swapTabValues();
			tabPreference.setEnabled(true);
			tabPreference.setKey(DefaultCodeFormatterConstants.FORMATTER_TAB_SIZE);
			indentPreference.setEnabled(false);
			indentPreference.setKey(DefaultCodeFormatterConstants.FORMATTER_TAB_SIZE);
		} else {
			Assert.isTrue(false);
		}
		fOldTabChar= tabPolicy;
	}
	private void swapTabValues() {
		Object tabSize= fWorkingValues.get(DefaultCodeFormatterConstants.FORMATTER_TAB_SIZE);
		Object indentSize= fWorkingValues.get(DefaultCodeFormatterConstants.FORMATTER_INDENTATION_SIZE);
		fWorkingValues.put(DefaultCodeFormatterConstants.FORMATTER_TAB_SIZE, indentSize);
		fWorkingValues.put(DefaultCodeFormatterConstants.FORMATTER_INDENTATION_SIZE, tabSize);
	}
}