The download site, as stated in the java-sdk-docs-1.5.0-r1 ebuild, is no longer available. Either punt the package (and any dependencies pointing at it, including those in java-overlay), or find a new download location.
Looks like it's totally gone.
i guess we should remove doc use flags from all these packages (or whole packages, if they do not work anymore): dev-java/blackdown-jdk-1.4.2.03-r17 (doc ? =dev-java/java-sdk-docs-1.4.2*) dev-java/ibm-jdk-bin-1.4.2.13-r1 (doc ? =dev-java/java-sdk-docs-1.4.2*) dev-java/ibm-jdk-bin-1.5.0.12_p4 (doc ? =dev-java/java-sdk-docs-1.5.0*) dev-java/ibm-jdk-bin-1.5.0.12_p5 (doc ? =dev-java/java-sdk-docs-1.5.0*) dev-java/jrockit-jdk-bin-1.5.0.14 (doc ? =dev-java/java-sdk-docs-1.5.0*) dev-java/sun-jdk-1.4.2.19-r1 (doc ? =dev-java/java-sdk-docs-1.4.2*) dev-java/sun-jdk-1.5.0.22-r1 (doc ? =dev-java/java-sdk-docs-1.5.0*) any objections?
1.5 related-stuff still in the tree? Wow. Let's remove it ASAP.
epsilon ~ # equery d -a dev-java/java-sdk-docs * These packages depend on dev-java/java-sdk-docs: dev-java/ibm-jdk-bin-1.6.0.9_p1 (doc ? =dev-java/java-sdk-docs-1.6.0*) dev-java/ibm-jdk-bin-1.6.0.9_p2 (doc ? =dev-java/java-sdk-docs-1.6.0*) dev-java/ibm-jdk-bin-1.6.0.9_p2-r1 (doc ? =dev-java/java-sdk-docs-1.6.0*) dev-java/oracle-jdk-bin-1.7.0.60 (doc ? dev-java/java-sdk-docs:1.7) dev-java/oracle-jdk-bin-1.7.0.76 (doc ? dev-java/java-sdk-docs:1.7) dev-java/oracle-jdk-bin-1.8.0.40-r1 (doc ? dev-java/java-sdk-docs:1.8) dev-java/oracle-jdk-bin-1.8.0.45 (doc ? dev-java/java-sdk-docs:1.8) dev-java/sun-jdk-1.6.0.45 (doc ? dev-java/java-sdk-docs:1.6.0) + 15 Jun 2015; Patrice Clement <monsieurp@gentoo.org> + -java-sdk-docs-1.5.0-r1.ebuild: + Drop old. +