bug 4355 - improve parse exception messages

11 files changed, 234 insertions, 136 deletions

diff --git a/java/src/Ice/ObjectAdapterI.java b/java/src/Ice/ObjectAdapterI.java
index b4bd577a414..c0243872304 100644
--- a/java/src/Ice/ObjectAdapterI.java
+++ b/java/src/Ice/ObjectAdapterI.java
@@ -1211,7 +1211,7 @@ public final class ObjectAdapterI implements ObjectAdapter
             if(endp == null)
             {
                 Ice.EndpointParseException e = new Ice.EndpointParseException();
-                e.str = s;
+                e.str = "invalid object adapter endpoint `" + s + "'";
                 throw e;
             }
             endpoints.add(endp);
diff --git a/java/src/Ice/Util.java b/java/src/Ice/Util.java
index dc4253eb627..04ea0dea312 100644
--- a/java/src/Ice/Util.java
+++ b/java/src/Ice/Util.java
@@ -252,7 +252,7 @@ public final class Util
                     // Extra unescaped slash found.
                     //
                     IdentityParseException ex = new IdentityParseException();
-                    ex.str = s;
+                    ex.str = "unescaped backslash in identity `" + s + "'";
                     throw ex;
                 }
             }
@@ -261,35 +261,42 @@ public final class Util
 
         if(slash == -1)
         {
-            StringHolder token = new StringHolder();
-            if(!IceUtilInternal.StringUtil.unescapeString(s, 0, s.length(), token))
+            ident.category = "";
+            try
+            {
+                ident.name = IceUtilInternal.StringUtil.unescapeString(s, 0, s.length());
+            }
+            catch(IllegalArgumentException e)
             {
                 IdentityParseException ex = new IdentityParseException();
-                ex.str = s;
+                ex.str = "invalid identity name `" + s + "': " + e.getMessage();
                 throw ex;
             }
-            ident.category = "";
-            ident.name = token.value;
         }
         else
         {
-            StringHolder token = new StringHolder();
-            if(!IceUtilInternal.StringUtil.unescapeString(s, 0, slash, token))
+            try
+            {
+                ident.category = IceUtilInternal.StringUtil.unescapeString(s, 0, slash);
+            }
+            catch(IllegalArgumentException e)
             {
                 IdentityParseException ex = new IdentityParseException();
-                ex.str = s;
+                ex.str = "invalid category in identity `" + s + "': " + e.getMessage();
                 throw ex;
             }
-            ident.category = token.value;
             if(slash + 1 < s.length())
             {
-                if(!IceUtilInternal.StringUtil.unescapeString(s, slash + 1, s.length(), token))
+                try
+                {
+                    ident.name = IceUtilInternal.StringUtil.unescapeString(s, slash + 1, s.length());
+                }
+                catch(IllegalArgumentException e)
                 {
                     IdentityParseException ex = new IdentityParseException();
-                    ex.str = s;
+                    ex.str = "invalid name in identity `" + s + "': " + e.getMessage();
                     throw ex;
                 }
-                ident.name = token.value;
             }
             else
             {
diff --git a/java/src/IceInternal/DefaultsAndOverrides.java b/java/src/IceInternal/DefaultsAndOverrides.java
index 8946bf6f7b7..ce340c66e1b 100644
--- a/java/src/IceInternal/DefaultsAndOverrides.java
+++ b/java/src/IceInternal/DefaultsAndOverrides.java
@@ -108,7 +108,7 @@ public final class DefaultsAndOverrides
         else
         {
             Ice.EndpointSelectionTypeParseException ex = new Ice.EndpointSelectionTypeParseException();
-            ex.str = value;
+            ex.str = "illegal value `" + value + "'; expected `Random' or `Ordered'";
             throw ex;
         }
 
diff --git a/java/src/IceInternal/EndpointFactoryManager.java b/java/src/IceInternal/EndpointFactoryManager.java
index de816428863..50b5e8d2ac7 100644
--- a/java/src/IceInternal/EndpointFactoryManager.java
+++ b/java/src/IceInternal/EndpointFactoryManager.java
@@ -51,7 +51,7 @@ public final class EndpointFactoryManager
         if(s.length() == 0)
         {
             Ice.EndpointParseException e = new Ice.EndpointParseException();
-            e.str = str;
+            e.str = "value has no non-whitespace characters";
             throw e;
         }
 
diff --git a/java/src/IceInternal/OpaqueEndpointI.java b/java/src/IceInternal/OpaqueEndpointI.java
index f4c9a8e1f3a..c85e27fedea 100644
--- a/java/src/IceInternal/OpaqueEndpointI.java
+++ b/java/src/IceInternal/OpaqueEndpointI.java
@@ -30,7 +30,8 @@ final class OpaqueEndpointI extends EndpointI
             String option = arr[i++];
             if(option.length() != 2 || option.charAt(0) != '-')
             {
-                throw new Ice.EndpointParseException("opaque " + str);
+                throw new Ice.EndpointParseException("expected an endpoint option but found `" + option +
+                                                     "' in endpoint `opaque " + str + "'");
             }
 
             String argument = null;
@@ -45,7 +46,8 @@ final class OpaqueEndpointI extends EndpointI
                 {
                     if(argument == null)
                     {
-                        throw new Ice.EndpointParseException("opaque " + str);
+                        throw new Ice.EndpointParseException("no argument provided for -t option in endpoint `opaque "
+                                                             + str + "'");
                     }
 
                     int t;
@@ -55,16 +57,22 @@ final class OpaqueEndpointI extends EndpointI
                     }
                     catch(NumberFormatException ex)
                     {
-                        throw new Ice.EndpointParseException("opaque " + str);
+                        throw new Ice.EndpointParseException("invalid timeout value `" + argument +
+                                                             "' in endpoint `opaque " + str + "'");
                     }
 
                     if(t < 0 || t > 65535)
                     {
-                        throw new Ice.EndpointParseException("opaque " + str);
+                        throw new Ice.EndpointParseException("timeout value `" + argument +
+                                                             "' out of range in endpoint `opaque " + str + "'");
                     }
 
                     _type = (short)t;
                     ++topt;
+                    if(topt > 1)
+                    {
+                        throw new Ice.EndpointParseException("multiple -t options in endpoint `opaque " + str + "'");
+                    }
                     break;
                 }
 
@@ -72,30 +80,42 @@ final class OpaqueEndpointI extends EndpointI
                 {
                     if(argument == null)
                     {
-                        throw new Ice.EndpointParseException("opaque " + str);
+                        throw new Ice.EndpointParseException("no argument provided for -v option in endpoint `opaque "
+                                                             + str + "'");
                     }
                     for(int j = 0; j < argument.length(); ++j)
                     {
                         if(!IceUtilInternal.Base64.isBase64(argument.charAt(j)))
                         {
-                            throw new Ice.EndpointParseException("opaque " + str);
+                            throw new Ice.EndpointParseException("invalid base64 character `" + argument.charAt(j) +
+                                                                 "' (ordinal " + ((int)argument.charAt(j)) +
+                                                                 ") in endpoint `opaque " + str + "'");
                         }
                     }
                     _rawBytes = IceUtilInternal.Base64.decode(argument);
                     ++vopt;
+                    if(vopt > 1)
+                    {
+                        throw new Ice.EndpointParseException("multiple -v options in endpoint `opaque " + str + "'");
+                    }
                     break;
                 }
 
                 default:
                 {
-                    throw new Ice.EndpointParseException("opaque " + str);
+                    throw new Ice.EndpointParseException("invalid option `" + option + "' in endpoint `opaque " +
+                                                         str + "'");
                 }
             }
         }
 
-        if(topt != 1 || vopt != 1)
+        if(topt != 1)
+        {
+            throw new Ice.EndpointParseException("no -t option in endpoint `opaque " + str + "'");
+        }
+        if(vopt != 1)
         {
-            throw new Ice.EndpointParseException("opaque " + str);
+            throw new Ice.EndpointParseException("no -v option in endpoint `opaque " + str + "'");
         }
         calcHashValue();
     }
diff --git a/java/src/IceInternal/ReferenceFactory.java b/java/src/IceInternal/ReferenceFactory.java
index 30a236394ec..574c121b1e0 100644
--- a/java/src/IceInternal/ReferenceFactory.java
+++ b/java/src/IceInternal/ReferenceFactory.java
@@ -83,7 +83,7 @@ public final class ReferenceFactory
         if(beg == -1)
         {
             Ice.ProxyParseException e = new Ice.ProxyParseException();
-            e.str = s;
+            e.str = "no non-whitespace characters found in `" + s + "'";
             throw e;
         }
 
@@ -96,7 +96,7 @@ public final class ReferenceFactory
         if(end == -1)
         {
             Ice.ProxyParseException e = new Ice.ProxyParseException();
-            e.str = s;
+            e.str = "mismatched quotes around identity in `" + s + "'";
             throw e;
         }
         else if(end == 0)
@@ -118,7 +118,7 @@ public final class ReferenceFactory
         if(beg == end)
         {
             Ice.ProxyParseException e = new Ice.ProxyParseException();
-            e.str = s;
+            e.str = "no identity in `" + s + "'";
             throw e;
         }
 
@@ -148,7 +148,7 @@ public final class ReferenceFactory
             else if(IceUtilInternal.StringUtil.findFirstNotOf(s, delim, end) != -1)
             {
                 Ice.ProxyParseException e = new Ice.ProxyParseException();
-                e.str = s;
+                e.str = "invalid characters after identity in `" + s + "'";
                 throw e;
             }
             else
@@ -190,7 +190,7 @@ public final class ReferenceFactory
             if(option.length() != 2 || option.charAt(0) != '-')
             {
                 Ice.ProxyParseException e = new Ice.ProxyParseException();
-                e.str = s;
+                e.str = "expected a proxy option but found `" + option + "' in `" + s + "'";
                 throw e;
             }
 
@@ -211,7 +211,7 @@ public final class ReferenceFactory
                     if(end == -1)
                     {
                         Ice.ProxyParseException e = new Ice.ProxyParseException();
-                        e.str = s;
+                        e.str = "mismatched quotes around value for " + option + " option in `" + s + "'";
                         throw e;
                     }
                     else if(end == 0)
@@ -243,19 +243,21 @@ public final class ReferenceFactory
                     if(argument == null)
                     {
                         Ice.ProxyParseException e = new Ice.ProxyParseException();
-                        e.str = s;
+                        e.str = "no argument provided for -f option in `" + s + "'";
                         throw e;
                     }
 
-                    Ice.StringHolder facetH = new Ice.StringHolder();
-                    if(!IceUtilInternal.StringUtil.unescapeString(argument, 0, argument.length(), facetH))
+                    try
+                    {
+                        facet = IceUtilInternal.StringUtil.unescapeString(argument, 0, argument.length());
+                    }
+                    catch(IllegalArgumentException ex)
                     {
                         Ice.ProxyParseException e = new Ice.ProxyParseException();
-                        e.str = s;
+                        e.str = "invalid facet in `" + s + "': " + ex.getMessage();
                         throw e;
                     }
 
-                    facet = facetH.value;
                     break;
                 }
 
@@ -264,7 +266,7 @@ public final class ReferenceFactory
                     if(argument != null)
                     {
                         Ice.ProxyParseException e = new Ice.ProxyParseException();
-                        e.str = s;
+                        e.str = "unexpected argument `" + argument + "' provided for -t option in `" + s + "'";
                         throw e;
                     }
                     mode = Reference.ModeTwoway;
@@ -276,7 +278,7 @@ public final class ReferenceFactory
                     if(argument != null)
                     {
                         Ice.ProxyParseException e = new Ice.ProxyParseException();
-                        e.str = s;
+                        e.str = "unexpected argument `" + argument + "' provided for -o option in `" + s + "'";
                         throw e;
                     }
                     mode = Reference.ModeOneway;
@@ -288,7 +290,7 @@ public final class ReferenceFactory
                     if(argument != null)
                     {
                         Ice.ProxyParseException e = new Ice.ProxyParseException();
-                        e.str = s;
+                        e.str = "unexpected argument `" + argument + "' provided for -O option in `" + s + "'";
                         throw e;
                     }
                     mode = Reference.ModeBatchOneway;
@@ -300,7 +302,7 @@ public final class ReferenceFactory
                     if(argument != null)
                     {
                         Ice.ProxyParseException e = new Ice.ProxyParseException();
-                        e.str = s;
+                        e.str = "unexpected argument `" + argument + "' provided for -d option in `" + s + "'";
                         throw e;
                     }
                     mode = Reference.ModeDatagram;
@@ -312,7 +314,7 @@ public final class ReferenceFactory
                     if(argument != null)
                     {
                         Ice.ProxyParseException e = new Ice.ProxyParseException();
-                        e.str = s;
+                        e.str = "unexpected argument `" + argument + "' provided for -D option in `" + s + "'";
                         throw e;
                     }
                     mode = Reference.ModeBatchDatagram;
@@ -324,7 +326,7 @@ public final class ReferenceFactory
                     if(argument != null)
                     {
                         Ice.ProxyParseException e = new Ice.ProxyParseException();
-                        e.str = s;
+                        e.str = "unexpected argument `" + argument + "' provided for -s option in `" + s + "'";
                         throw e;
                     }
                     secure = true;
@@ -334,7 +336,7 @@ public final class ReferenceFactory
                 default:
                 {
                     Ice.ProxyParseException e = new Ice.ProxyParseException();
-                    e.str = s;
+                    e.str = "unknown option `" + option + "' in `" + s + "'";
                     throw e;
                 }
             }
@@ -412,8 +414,9 @@ public final class ReferenceFactory
             }
             if(endpoints.size() == 0)
             {
+                assert(!unknownEndpoints.isEmpty());
                 Ice.EndpointParseException e = new Ice.EndpointParseException();
-                e.str = unknownEndpoints.get(0);
+                e.str = "invalid endpoint `" + unknownEndpoints.get(0) + "' in `" + s + "'";
                 throw e;
             }
             else if(unknownEndpoints.size() != 0 &&
@@ -439,7 +442,7 @@ public final class ReferenceFactory
             if(beg == -1)
             {
                 Ice.ProxyParseException e = new Ice.ProxyParseException();
-                e.str = s;
+                e.str = "missing adapter id in `" + s + "'";
                 throw e;
             }
 
@@ -448,7 +451,7 @@ public final class ReferenceFactory
             if(end == -1)
             {
                 Ice.ProxyParseException e = new Ice.ProxyParseException();
-                e.str = s;
+                e.str = "mismatched quotes around adapter id in `" + s + "'";
                 throw e;
             }
             else if(end == 0)
@@ -470,24 +473,31 @@ public final class ReferenceFactory
             if(end != s.length() && IceUtilInternal.StringUtil.findFirstNotOf(s, delim, end) != -1)
             {
                 Ice.ProxyParseException e = new Ice.ProxyParseException();
-                e.str = s;
+                e.str = "invalid trailing characters after `" + s.substring(0, end + 1) + "' in `" + s + "'";
                 throw e;
             }
-            
-            Ice.StringHolder token = new Ice.StringHolder();
-            if(!IceUtilInternal.StringUtil.unescapeString(adapterstr, 0, adapterstr.length(), token) ||
-               token.value.length() == 0)
+
+            try
+            {
+                adapter = IceUtilInternal.StringUtil.unescapeString(adapterstr, 0, adapterstr.length());
+            }
+            catch(IllegalArgumentException ex)
+            {
+                Ice.ProxyParseException e = new Ice.ProxyParseException();
+                e.str = "invalid adapter id in `" + s + "': " + ex.getMessage();
+                throw e;
+            }
+            if(adapter.length() == 0)
             {
                 Ice.ProxyParseException e = new Ice.ProxyParseException();
-                e.str = s;
+                e.str = "empty adapter id in `" + s + "'";
                 throw e;
             }
-            adapter = token.value;
             return create(ident, facet, mode, secure, null, adapter, propertyPrefix);
         }
 
         Ice.ProxyParseException ex = new Ice.ProxyParseException();
-        ex.str = s;
+        ex.str = "malformed proxy `" + s + "'";
         throw ex;
     }
 
@@ -782,7 +792,8 @@ public final class ReferenceFactory
                 }
                 else
                 {
-                    throw new Ice.EndpointSelectionTypeParseException(type);
+                    throw new Ice.EndpointSelectionTypeParseException("illegal value `" + type +
+                                                                      "'; expected `Random' or `Ordered'");
                 }
             }
         
diff --git a/java/src/IceInternal/TcpEndpointI.java b/java/src/IceInternal/TcpEndpointI.java
index 27618d8ccc5..f331068a9e8 100644
--- a/java/src/IceInternal/TcpEndpointI.java
+++ b/java/src/IceInternal/TcpEndpointI.java
@@ -46,7 +46,8 @@ final class TcpEndpointI extends EndpointI
             String option = arr[i++];
             if(option.length() != 2 || option.charAt(0) != '-')
             {
-                throw new Ice.EndpointParseException("tcp " + str);
+                throw new Ice.EndpointParseException("expected an endpoint option but found `" + option +
+                                                     "' in endpoint `tcp " + str + "'");
             }
 
             String argument = null;
@@ -65,7 +66,8 @@ final class TcpEndpointI extends EndpointI
                 {
                     if(argument == null)
                     {
-                        throw new Ice.EndpointParseException("tcp " + str);
+                        throw new Ice.EndpointParseException("no argument provided for -h option in endpoint `tcp "
+                                                             + str + "'");
                     }
 
                     _host = argument;
@@ -76,7 +78,8 @@ final class TcpEndpointI extends EndpointI
                 {
                     if(argument == null)
                     {
-                        throw new Ice.EndpointParseException("tcp " + str);
+                        throw new Ice.EndpointParseException("no argument provided for -p option in endpoint `tcp "
+                                                             + str + "'");
                     }
 
                     try
@@ -85,12 +88,14 @@ final class TcpEndpointI extends EndpointI
                     }
                     catch(NumberFormatException ex)
                     {
-                        throw new Ice.EndpointParseException("tcp " + str);
+                        throw new Ice.EndpointParseException("invalid port value `" + argument +
+                                                             "' in endpoint `tcp " + str + "'");
                     }
 
                     if(_port < 0 || _port > 65535)
                     {
-                        throw new Ice.EndpointParseException("tcp " + str);
+                        throw new Ice.EndpointParseException("port value `" + argument +
+                                                             "' out of range in endpoint `tcp " + str + "'");
                     }
 
                     break;
@@ -100,7 +105,8 @@ final class TcpEndpointI extends EndpointI
                 {
                     if(argument == null)
                     {
-                        throw new Ice.EndpointParseException("tcp " + str);
+                        throw new Ice.EndpointParseException("no argument provided for -t option in endpoint `tcp "
+                                                             + str + "'");
                     }
 
                     try
@@ -109,7 +115,8 @@ final class TcpEndpointI extends EndpointI
                     }
                     catch(NumberFormatException ex)
                     {
-                        throw new Ice.EndpointParseException("tcp " + str);
+                        throw new Ice.EndpointParseException("invalid timeout value `" + argument +
+                                                             "' in endpoint `tcp " + str + "'");
                     }
 
                     break;
@@ -119,7 +126,8 @@ final class TcpEndpointI extends EndpointI
                 {
                     if(argument != null)
                     {
-                        throw new Ice.EndpointParseException("tcp " + str);
+                        throw new Ice.EndpointParseException("unexpected argument `" + argument +
+                                                             "' provided for -z option in `tcp " + str + "'");
                     }
 
                     _compress = true;
@@ -128,7 +136,7 @@ final class TcpEndpointI extends EndpointI
 
                 default:
                 {
-                    throw new Ice.EndpointParseException("tcp " + str);
+                    throw new Ice.EndpointParseException("unknown option `" + option + "' in `tcp " + str + "'");
                 }
             }
         }
@@ -145,7 +153,7 @@ final class TcpEndpointI extends EndpointI
             }
             else
             {
-                throw new Ice.EndpointParseException("tcp " + str);
+                throw new Ice.EndpointParseException("`-h *' not valid for proxy endpoint `tcp " + str + "'");
             }
         }
 
diff --git a/java/src/IceInternal/UdpEndpointI.java b/java/src/IceInternal/UdpEndpointI.java
index 880eae25473..153b9f99a96 100644
--- a/java/src/IceInternal/UdpEndpointI.java
+++ b/java/src/IceInternal/UdpEndpointI.java
@@ -57,7 +57,8 @@ final class UdpEndpointI extends EndpointI
             String option = arr[i++];
             if(option.charAt(0) != '-')
             {
-                throw new Ice.EndpointParseException("udp " + str);
+                throw new Ice.EndpointParseException("expected an endpoint option but found `" + option +
+                                                     "' in endpoint `udp " + str + "'");
             }
 
             String argument = null;
@@ -74,13 +75,15 @@ final class UdpEndpointI extends EndpointI
             {
                 if(argument == null)
                 {
-                    throw new Ice.EndpointParseException("udp " + str);
+                    throw new Ice.EndpointParseException("no argument provided for -v option in endpoint `udp "
+                                                         + str + "'");
                 }
 
                 int pos = argument.indexOf('.');
                 if(pos == -1)
                 {
-                    throw new Ice.EndpointParseException("udp " + str);
+                    throw new Ice.EndpointParseException("malformed protocol version `" + argument +
+                                                         "' in endpoint `udp " + str + "'");
                 }
 
                 String majStr = argument.substring(0, pos);
@@ -94,12 +97,14 @@ final class UdpEndpointI extends EndpointI
                 }
                 catch(NumberFormatException ex)
                 {
-                    throw new Ice.EndpointParseException("udp " + str);
+                    throw new Ice.EndpointParseException("invalid protocol version `" + argument +
+                                                         "' in endpoint `udp " + str + "'");
                 }
 
                 if(majVersion < 1 || majVersion > 255 || minVersion < 0 || minVersion > 255)
                 {
-                    throw new Ice.EndpointParseException("udp " + str);
+                    throw new Ice.EndpointParseException("range error in protocol version `" + argument +
+                                                         "' in endpoint `udp " + str + "'");
                 }
 
                 if(majVersion != Protocol.protocolMajor)
@@ -119,13 +124,15 @@ final class UdpEndpointI extends EndpointI
             {
                 if(argument == null)
                 {
-                    throw new Ice.EndpointParseException("udp " + str);
+                    throw new Ice.EndpointParseException("no argument provided for -e option in endpoint `udp "
+                                                         + str + "'");
                 }
 
                 int pos = argument.indexOf('.');
                 if(pos == -1)
                 {
-                    throw new Ice.EndpointParseException("udp " + str);
+                    throw new Ice.EndpointParseException("malformed encoding version `" + argument +
+                                                         "' in endpoint `udp " + str + "'");
                 }
 
                 String majStr = argument.substring(0, pos);
@@ -139,12 +146,14 @@ final class UdpEndpointI extends EndpointI
                 }
                 catch(NumberFormatException ex)
                 {
-                    throw new Ice.EndpointParseException("udp " + str);
+                    throw new Ice.EndpointParseException("invalid encoding version `" + argument +
+                                                         "' in endpoint `udp " + str + "'");
                 }
 
                 if(majVersion < 1 || majVersion > 255 || minVersion < 0 || minVersion > 255)
                 {
-                    throw new Ice.EndpointParseException("udp " + str);
+                    throw new Ice.EndpointParseException("range error in encoding version `" + argument +
+                                                         "' in endpoint `udp " + str + "'");
                 }
 
                 if(majVersion != Protocol.encodingMajor)
@@ -164,7 +173,8 @@ final class UdpEndpointI extends EndpointI
             {
                 if(argument == null)
                 {
-                    throw new Ice.EndpointParseException("udp " + str);
+                    throw new Ice.EndpointParseException("no argument provided for -h option in endpoint `udp "
+                                                         + str + "'");
                 }
 
                 _host = argument;
@@ -173,7 +183,8 @@ final class UdpEndpointI extends EndpointI
             {
                 if(argument == null)
                 {
-                    throw new Ice.EndpointParseException("udp " + str);
+                    throw new Ice.EndpointParseException("no argument provided for -p option in endpoint `udp "
+                                                         + str + "'");
                 }
 
                 try
@@ -182,19 +193,22 @@ final class UdpEndpointI extends EndpointI
                 }
                 catch(NumberFormatException ex)
                 {
-                    throw new Ice.EndpointParseException("udp " + str);
+                    throw new Ice.EndpointParseException("invalid port value `" + argument + "' in endpoint `udp " +
+                                                         str + "'");
                 }
 
                 if(_port < 0 || _port > 65535)
                 {
-                    throw new Ice.EndpointParseException("udp " + str);
+                    throw new Ice.EndpointParseException("port value `" + argument +
+                                                         "' out of range in endpoint `udp " + str + "'");
                 }
             }
             else if(option.equals("-c"))
             {
                 if(argument != null)
                 {
-                    throw new Ice.EndpointParseException("udp " + str);
+                    throw new Ice.EndpointParseException("unexpected argument `" + argument +
+                                                         "' provided for -c option in `udp " + str + "'");
                 }
 
                 _connect = true;
@@ -204,7 +218,8 @@ final class UdpEndpointI extends EndpointI
             {
                 if(argument != null)
                 {
-                    throw new Ice.EndpointParseException("udp " + str);
+                    throw new Ice.EndpointParseException("unexpected argument `" + argument +
+                                                         "' provided for -z option in `udp " + str + "'");
                 }
 
                 _compress = true;
@@ -214,7 +229,8 @@ final class UdpEndpointI extends EndpointI
             {
                 if(argument == null)
                 {
-                    throw new Ice.EndpointParseException("udp " + str);
+                    throw new Ice.EndpointParseException("no argument provided for --interface option in endpoint `udp "
+                                                         + str + "'");
                 }
 
                 _mcastInterface = argument;
@@ -223,7 +239,8 @@ final class UdpEndpointI extends EndpointI
             {
                 if(argument == null)
                 {
-                    throw new Ice.EndpointParseException("udp " + str);
+                    throw new Ice.EndpointParseException("no argument provided for --ttl option in endpoint `udp "
+                                                         + str + "'");
                 }
 
                 try
@@ -232,17 +249,19 @@ final class UdpEndpointI extends EndpointI
                 }
                 catch(NumberFormatException ex)
                 {
-                    throw new Ice.EndpointParseException("udp " + str);
+                    throw new Ice.EndpointParseException("invalid TTL value `" + argument + "' in endpoint `udp " +
+                                                         str + "'");
                 }
 
                 if(_mcastTtl < 0)
                 {
-                    throw new Ice.EndpointParseException("udp " + str);
+                    throw new Ice.EndpointParseException("TTL value `" + argument +
+                                                         "' out of range in endpoint `udp " + str + "'");
                 }
             }
             else
             {
-                throw new Ice.EndpointParseException("udp " + str);
+                throw new Ice.EndpointParseException("unknown option `" + option + "' in `udp " + str + "'");
             }
         }
 
@@ -258,7 +277,7 @@ final class UdpEndpointI extends EndpointI
             }
             else
             {
-                throw new Ice.EndpointParseException("udp " + str);
+                throw new Ice.EndpointParseException("`-h *' not valid for proxy endpoint `udp " + str + "'");
             }
         }
 
diff --git a/java/src/IceSSL/EndpointI.java b/java/src/IceSSL/EndpointI.java
index 9c0282750da..97837176a0c 100644
--- a/java/src/IceSSL/EndpointI.java
+++ b/java/src/IceSSL/EndpointI.java
@@ -46,7 +46,8 @@ final class EndpointI extends IceInternal.EndpointI
             String option = arr[i++];
             if(option.length() != 2 || option.charAt(0) != '-')
             {
-                throw new Ice.EndpointParseException("ssl " + str);
+                throw new Ice.EndpointParseException("expected an endpoint option but found `" + option +
+                                                     "' in endpoint `ssl " + str + "'");
             }
 
             String argument = null;
@@ -65,7 +66,8 @@ final class EndpointI extends IceInternal.EndpointI
                 {
                     if(argument == null)
                     {
-                        throw new Ice.EndpointParseException("ssl " + str);
+                        throw new Ice.EndpointParseException("no argument provided for -h option in endpoint `ssl "
+                                                             + str + "'");
                     }
 
                     _host = argument;
@@ -76,7 +78,8 @@ final class EndpointI extends IceInternal.EndpointI
                 {
                     if(argument == null)
                     {
-                        throw new Ice.EndpointParseException("ssl " + str);
+                        throw new Ice.EndpointParseException("no argument provided for -p option in endpoint `ssl "
+                                                             + str + "'");
                     }
 
                     try
@@ -85,12 +88,14 @@ final class EndpointI extends IceInternal.EndpointI
                     }
                     catch(NumberFormatException ex)
                     {
-                        throw new Ice.EndpointParseException("ssl " + str);
+                        throw new Ice.EndpointParseException("invalid port value `" + argument +
+                                                             "' in endpoint `ssl " + str + "'");
                     }
 
                     if(_port < 0 || _port > 65535)
                     {
-                        throw new Ice.EndpointParseException("ssl " + str);
+                        throw new Ice.EndpointParseException("port value `" + argument +
+                                                             "' out of range in endpoint `ssl " + str + "'");
                     }
 
                     break;
@@ -100,7 +105,8 @@ final class EndpointI extends IceInternal.EndpointI
                 {
                     if(argument == null)
                     {
-                        throw new Ice.EndpointParseException("ssl " + str);
+                        throw new Ice.EndpointParseException("no argument provided for -t option in endpoint `ssl "
+                                                             + str + "'");
                     }
 
                     try
@@ -109,7 +115,8 @@ final class EndpointI extends IceInternal.EndpointI
                     }
                     catch(NumberFormatException ex)
                     {
-                        throw new Ice.EndpointParseException("ssl " + str);
+                        throw new Ice.EndpointParseException("invalid timeout value `" + argument +
+                                                             "' in endpoint `ssl " + str + "'");
                     }
 
                     break;
@@ -119,7 +126,8 @@ final class EndpointI extends IceInternal.EndpointI
                 {
                     if(argument != null)
                     {
-                        throw new Ice.EndpointParseException("ssl " + str);
+                        throw new Ice.EndpointParseException("unexpected argument `" + argument +
+                                                             "' provided for -z option in `ssl " + str + "'");
                     }
 
                     _compress = true;
@@ -128,7 +136,7 @@ final class EndpointI extends IceInternal.EndpointI
 
                 default:
                 {
-                    throw new Ice.EndpointParseException("ssl " + str);
+                    throw new Ice.EndpointParseException("unknown option `" + option + "' in `ssl " + str + "'");
                 }
             }
         }
@@ -145,7 +153,7 @@ final class EndpointI extends IceInternal.EndpointI
             }
             else
             {
-                throw new Ice.EndpointParseException("ssl " + str);
+                throw new Ice.EndpointParseException("`-h *' not valid for proxy endpoint `ssl " + str + "'");
             }
         }
 
diff --git a/java/src/IceUtilInternal/StringUtil.java b/java/src/IceUtilInternal/StringUtil.java
index befc624f425..137bb234e06 100644
--- a/java/src/IceUtilInternal/StringUtil.java
+++ b/java/src/IceUtilInternal/StringUtil.java
@@ -199,11 +199,22 @@ public final class StringUtil
     }
 
     private static char
-    checkChar(char c)
+    checkChar(String s, int pos)
     {
+        char c = s.charAt(pos);
         if(!(c >= 32 && c <= 126))
         {
-            throw new IllegalArgumentException("illegal input character");
+            String msg;
+            if(pos > 0)
+            {
+                msg = "character after `" + s.substring(0, pos) + "'";
+            }
+            else
+            {
+                msg = "first character";
+            }
+            msg += " is not a printable ASCII character (ordinal " + (int)c + ")";
+            throw new IllegalArgumentException(msg);
         }
         return c;
     }
@@ -223,13 +234,13 @@ public final class StringUtil
 
         if(s.charAt(start) != '\\')
         {
-            c = checkChar(s.charAt(start++));
+            c = checkChar(s, start++);
         }
         else
         {
             if(start + 1 == end)
             {
-                throw new IllegalArgumentException("trailing backslash in argument");
+                throw new IllegalArgumentException("trailing backslash");
             }
             switch(s.charAt(++start))
             {
@@ -279,7 +290,7 @@ public final class StringUtil
                 case '6':
                 case '7':
                 {
-                    int oct = 0;
+                    int val = 0;
                     for(int j = 0; j < 3 && start < end; ++j)
                     {
                         int charVal = s.charAt(start++) - '0';
@@ -288,18 +299,19 @@ public final class StringUtil
                             --start;
                             break;
                         }
-                        oct = oct * 8 + charVal;
+                        val = val * 8 + charVal;
                     }
-                    if(oct > 255)
+                    if(val > 255)
                     {
-                        throw new IllegalArgumentException("octal value out of range");
+                        String msg = "octal value \\" + Integer.toOctalString(val) + " (" + val + ") is out of range";
+                        throw new IllegalArgumentException(msg);
                     }
-                    c = (char)oct;
+                    c = (char)val;
                     break;
                 }
                 default:
                 {
-                    c = checkChar(s.charAt(start++));
+                    c = checkChar(s, start++);
                     break;
                 }
             }
@@ -324,42 +336,33 @@ public final class StringUtil
     }
 
     //
-    // Remove escape sequences added by escapeString.
+    // Remove escape sequences added by escapeString. Throws IllegalArgumentException
+    // for an invalid input string.
     //
-    public static boolean
-    unescapeString(String s, int start, int end, Ice.StringHolder result)
+    public static String
+    unescapeString(String s, int start, int end)
     {
-        if(start < 0)
-        {
-            throw new IllegalArgumentException("start offset must be >= 0");
-        }
-        if(end > s.length())
-        {
-            throw new IllegalArgumentException("end offset must <= s.length()");
-        }
-        if(start > end)
+        assert(start >= 0 && start <= end && end <= s.length());
+
+        StringBuilder sb = new StringBuilder(end - start);
+        decodeString(s, start, end, sb);
+        String decodedString = sb.toString();
+
+        byte[] arr = new byte[decodedString.length()];
+        for(int i = 0; i < arr.length; ++i)
         {
-            throw new IllegalArgumentException("start offset must <= end offset");
+            arr[i] = (byte)decodedString.charAt(i);
         }
 
         try
         {
-            StringBuilder sb = new StringBuilder(end - start);
-            decodeString(s, start, end, sb);
-            String decodedString = sb.toString();
-
-            byte[] arr = new byte[decodedString.length()];
-            for(int i = 0; i < arr.length; ++i)
-            {
-                arr[i] = (byte)decodedString.charAt(i);
-            }
-
-            result.value = new String(arr, 0, arr.length, "UTF8");
-            return true;
+            return new String(arr, 0, arr.length, "UTF8");
         }
-        catch(java.lang.Exception ex)
+        catch(java.io.UnsupportedEncodingException ex)
         {
-            return false;
+            IllegalArgumentException e = new IllegalArgumentException("unsupported encoding");
+            e.initCause(ex);
+            throw e;
         }
     }
 
diff --git a/java/test/Ice/proxy/AllTests.java b/java/test/Ice/proxy/AllTests.java
index 39d772b08e9..678a0b9cf52 100644
--- a/java/test/Ice/proxy/AllTests.java
+++ b/java/test/Ice/proxy/AllTests.java
@@ -99,12 +99,34 @@ public class AllTests
         test(b1.ice_getIdentity().name.equals("test\1114test"));
 
         b1 = communicator.stringToProxy("test\\b\\f\\n\\r\\t\\'\\\"\\\\test");
-        test(b1.ice_getIdentity().name.equals("test\b\f\n\r\t\'\"\\test") && b1.ice_getIdentity().category.length() == 0);
+        test(b1.ice_getIdentity().name.equals("test\b\f\n\r\t\'\"\\test") &&
+             b1.ice_getIdentity().category.length() == 0);
 
         b1 = communicator.stringToProxy("category/test");
         test(b1.ice_getIdentity().name.equals("test") && b1.ice_getIdentity().category.equals("category") &&
              b1.ice_getAdapterId().length() == 0);
-             
+
+        b1 = communicator.stringToProxy("");
+        test(b1 == null);
+        b1 = communicator.stringToProxy("\"\"");
+        test(b1 == null);
+        try
+        {
+            b1 = communicator.stringToProxy("\"\" test"); // Invalid trailing characters.
+            test(false);
+        }
+        catch(Ice.ProxyParseException ex)
+        {
+        }
+        try
+        {
+            b1 = communicator.stringToProxy("test:"); // Missing endpoint.
+            test(false);
+        }
+        catch(Ice.EndpointParseException ex)
+        {
+        }
+
         b1 = communicator.stringToProxy("test@adapter");
         test(b1.ice_getIdentity().name.equals("test") && b1.ice_getIdentity().category.length() == 0 &&
              b1.ice_getAdapterId().equals("adapter"));
@@ -637,7 +659,7 @@ public class AllTests
             Ice.ObjectPrx p1 = communicator.stringToProxy("test:opaque -t 1 -v CTEyNy4wLjAuMeouAAAQJwAAAA==");
             String pstr = communicator.proxyToString(p1);
             test(pstr.equals("test -t:tcp -h 127.0.0.1 -p 12010 -t 10000"));
-        
+
             // Working?
             boolean ssl = communicator.getProperties().getProperty("Ice.Default.Protocol").equals("ssl");
             if(!ssl)