needed for applet search

[jalview.git] / src / com / stevesoft / pat / Skip.java

diff --git a/src/com/stevesoft/pat/Skip.java b/src/com/stevesoft/pat/Skip.java
new file mode 100755 (executable)
index 0000000..664c712
--- /dev/null
+++ b/src/com/stevesoft/pat/Skip.java
@@ -0,0 +1,127 @@
+//\r
+// This software is now distributed according to\r
+// the Lesser Gnu Public License.  Please see\r
+// http://www.gnu.org/copyleft/lesser.txt for\r
+// the details.\r
+//    -- Happy Computing!\r
+//\r
+package com.stevesoft.pat;\r
+\r
+/** This class is used internally to search ahead for some\r
+    optimized Regex objects.  It searches within a String\r
+    for occrences of a given String -- like a more flexible\r
+    version of String.indexOf.\r
+    @see com.stevesoft.pat.Skip2\r
+    @see com.stevesoft.pat.SkipBMH\r
+    */\r
+public class Skip {\r
+    static int mkmask(int c) {\r
+        char x = (char)c;\r
+        return ~( CaseMgr.toUpperCase(x) |\r
+            CaseMgr.toLowerCase(x) |\r
+            CaseMgr.toTitleCase(x));\r
+    }\r
+    static { int x = Regex.BackRefOffset; }\r
+    String src;\r
+    int c,mask;\r
+    int offset;\r
+    boolean ign,m1;\r
+    /** Examine a Regex to determine what String it will\r
+        attempt to skip to when searching for patterns.\r
+        Return -1 if we aren't doing this. */\r
+    public static String string(Regex r) {\r
+        return r.skipper == null ? null : r.skipper.src;\r
+    }\r
+    /** Determine the offset of the String within the pattern\r
+        that we are skipping to. Return -1 if we aren't doing\r
+        this.  */\r
+    public static int offset(Regex r) {\r
+        return r.skipper == null ? -1 : r.skipper.offset;\r
+    }\r
+    /** Initialize, give it a String to search for, tell it\r
+        whether or not to ignoreCase, and what the offset is\r
+        of the String within the String to be searched. */\r
+    public Skip(String s,boolean ign,int o) {\r
+        src = s;\r
+        c = s.charAt(0);\r
+        if(ign) {\r
+            mask = mkmask(c);\r
+        } else mask = 0;\r
+        offset = o;\r
+        this.ign = ign;\r
+        m1 = (s.length()==1);\r
+    }\r
+    /** The same as find(s,0,s.length()) */\r
+    public final int find(StringLike s) {\r
+        return find(s,0,s.length());\r
+    }\r
+    static final int min(int a,int b) { return a<b ? a : b; }\r
+    /** Searches a given region of text beginning at position start\r
+        and ending at position end for the skip object. */\r
+    public int find(StringLike s,int start,int end) {\r
+        if(start > end) return -1;\r
+        start += offset;\r
+        int vend = min(s.length()-1,end+offset);\r
+        if(mask != c) {\r
+            for(int i=start;i<=vend;i++)\r
+                if(0 == (s.charAt(i) & mask))\r
+                    //if(m1||s.regionMatches(ign,i,src,0,src.length()) )\r
+                    if(m1||CaseMgr.regionMatches(s,ign,i,src,0,src.length()) )\r
+                        return i-offset;\r
+        } else {\r
+            for(int i=start;i<=vend;i++)\r
+                if(c == s.charAt(i))\r
+                    //if(m1||s.regionMatches(ign,i,src,0,src.length()) )\r
+                    if(m1||CaseMgr.regionMatches(s,ign,i,src,0,src.length()) )\r
+                        return i-offset;\r
+        }\r
+        return -1;\r
+    }\r
+    static Skip findSkip(Regex r) {\r
+        return findSkip(r.thePattern,r.ignoreCase,!r.dontMatchInQuotes);\r
+    }\r
+    // look for things that can be skipped\r
+    static Skip findSkip(Pattern p,boolean ignoreCase,boolean trnc) {\r
+        StringBuffer sb = new StringBuffer();\r
+        Skip subsk = null;\r
+        int offset = 0;\r
+        int skipc = -1,skipoff=0;\r
+        for(;p != null;p = p.next) {\r
+            if(p instanceof oneChar) {\r
+                skipc = ((oneChar)p).c;\r
+                skipoff = offset;\r
+            }\r
+            if(p instanceof oneChar && p.next instanceof oneChar) {\r
+                Pattern psav = p;\r
+                sb.append(((oneChar)p).c);\r
+                while(p.next instanceof oneChar) {\r
+                    sb.append(((oneChar)p.next).c);\r
+                    p = p.next;\r
+                }\r
+                String st = sb.toString();\r
+                char c0 = st.charAt(0), c1 = st.charAt(1);\r
+                Skip sk=null;\r
+                if(st.length()>2)\r
+                    sk = new SkipBMH(st,ignoreCase,offset);\r
+                else\r
+                    sk = new Skip2(st,ignoreCase,offset);\r
+                if(trnc && st.length()>2) { // chop out a whole string...\r
+                    psav.next = new Skipped(st.substring(1));\r
+                    psav.next.next = p.next;\r
+                    psav.next.parent = p.parent;\r
+                }\r
+                return sk;\r
+            } else if(p instanceof Or && ((Or)p).v.size()==1\r
+                    && !((Or)p).leftForm().equals("(?!")\r
+                    && null != (subsk=\r
+                    findSkip( (Pattern)((Or)p).v.elementAt(0),ignoreCase,trnc) )) {\r
+                subsk.offset += offset;\r
+                return subsk;\r
+            } else if(p.minChars().equals(p.maxChars())) {\r
+                offset += p.minChars().intValue();\r
+            } else return skipc < 0 ? null :\r
+                new Skip(""+(char)skipc,ignoreCase,skipoff);\r
+        }\r
+        return null;\r
+    }\r
+}\r