FULL PRODUCT VERSION :
$ java -version
java version "1.7.0_05"
Java(TM) SE Runtime Environment (build 1.7.0_05-b05)
Java HotSpot(TM) 64-Bit Server VM (build 23.1-b03, mixed mode)

ADDITIONAL OS VERSION INFORMATION :
Linux <host> 2.6.18-92.el5 #1 SMP Tue Apr 29 13:16:15 EDT 2008 x86_64 x86_64 x86_64 GNU/Linux


A DESCRIPTION OF THE PROBLEM :
Compiling the source code included with this bug report results in a NullPointerException in the Java 1.7.0_05 compiler, at least on Linux x86_64.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Save the source code included with this bug report as a file named SwitchString.java and compile it with:
  javac SwitchString.java

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
The provided source code should compile successfully.
ACTUAL -
The Java compiler aborts the compilation due to a NullPointerException.

ERROR MESSAGES/STACK TRACES THAT OCCUR :
$ javac SwitchString.java
An exception has occurred in the compiler (1.7.0_05). Please file a bug at the Java Developer Connection (http://java.sun.com/webapps/bugreport) after checking the Bug Parade for duplicates. Include your program and the following diagnostic in your report. Thank you.
java.lang.NullPointerException
        at com.sun.tools.javac.comp.Lower.visitStringSwitch(Lower.java:3465)
        at com.sun.tools.javac.comp.Lower.visitSwitch(Lower.java:3365)
        at com.sun.tools.javac.tree.JCTree$JCSwitch.accept(JCTree.java:959)
        at com.sun.tools.javac.tree.TreeTranslator.translate(TreeTranslator.java:58)
        at com.sun.tools.javac.comp.Lower.translate(Lower.java:2160)
        at com.sun.tools.javac.tree.TreeTranslator.translate(TreeTranslator.java:70)
        at com.sun.tools.javac.tree.TreeTranslator.visitBlock(TreeTranslator.java:160)
        at com.sun.tools.javac.comp.Lower.visitBlock(Lower.java:3319)
        at com.sun.tools.javac.tree.JCTree$JCBlock.accept(JCTree.java:781)
        at com.sun.tools.javac.tree.TreeTranslator.translate(TreeTranslator.java:58)
        at com.sun.tools.javac.comp.Lower.translate(Lower.java:2160)
        at com.sun.tools.javac.tree.TreeTranslator.visitMethodDef(TreeTranslator.java:144)
        at com.sun.tools.javac.comp.Lower.visitMethodDefInternal(Lower.java:2627)
        at com.sun.tools.javac.comp.Lower.visitMethodDef(Lower.java:2546)
        at com.sun.tools.javac.tree.JCTree$JCMethodDecl.accept(JCTree.java:669)
        at com.sun.tools.javac.tree.TreeTranslator.translate(TreeTranslator.java:58)
        at com.sun.tools.javac.comp.Lower.translate(Lower.java:2160)
        at com.sun.tools.javac.comp.Lower.visitClassDef(Lower.java:2291)
        at com.sun.tools.javac.tree.JCTree$JCClassDecl.accept(JCTree.java:591)
        at com.sun.tools.javac.tree.TreeTranslator.translate(TreeTranslator.java:58)
        at com.sun.tools.javac.comp.Lower.translate(Lower.java:2160)
        at com.sun.tools.javac.comp.Lower.translate(Lower.java:2180)
        at com.sun.tools.javac.comp.Lower.translateTopLevelClass(Lower.java:3659)
        at com.sun.tools.javac.main.JavaCompiler.desugar(JavaCompiler.java:1395)
        at com.sun.tools.javac.main.JavaCompiler.desugar(JavaCompiler.java:1273)
        at com.sun.tools.javac.main.JavaCompiler.compile2(JavaCompiler.java:870)
        at com.sun.tools.javac.main.JavaCompiler.compile(JavaCompiler.java:829)
        at com.sun.tools.javac.main.Main.compile(Main.java:439)
        at com.sun.tools.javac.main.Main.compile(Main.java:353)
        at com.sun.tools.javac.main.Main.compile(Main.java:342)
        at com.sun.tools.javac.main.Main.compile(Main.java:333)
        at com.sun.tools.javac.Main.compile(Main.java:76)
        at com.sun.tools.javac.Main.main(Main.java:61)

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
/*
 * Compiling this program with the 1.7.0_05 Java compiler, at least on Linux
 * x86_64, causes the compiler to abort due to a NullPointerException.
 *
 * To reproduce the NPE, compile with:
 * javac SwitchString.java
 *
 * This test case was constructed to test the use of strings in switch
 * statements as provided by Java 7 language enhancements. It was drafted
 * based on the following clauses from JLS 7 (JSR-000901):
 *
 * 14.11 The switch Statement
 * ...
 * These labels are said to be associated with the switch statement, as are
 * the values of the constant expressions (15.28) or enum constants (8.9.1)
 * in the case labels.
 *
 * 15.28 Constant Expressions
 * ...
 * A compile-time constant expression is an expression denoting a value of
 * primitive type or a String that does not complete abruptly and is composed
 * using only the following:
 * ...
 * - Casts to primitive types and casts to type String (15.16)
 *
 * The cast to String in the case label below has no semantic relevance, but
 * is permitted according to JLS 7 (JSR-000901)
 */

public class SwitchString {
    public static void main(String [] args) {
        switch (args[0]) {
            case (String)"text":
                break;
        }
    }
}

---------- END SOURCE ----------